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				4	<head>
				5	<title>LLVM Assembly Language Reference Manual</title>
Reid Spencer	cb84e43	2004-08-26 20:44:00 +0000	[diff] [blame]	6	<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
				7	<meta name="author" content="Chris Lattner">
				8	<meta name="description"
				9	content="LLVM Assembly Language Reference Manual.">
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	10	<link rel="stylesheet" href="llvm.css" type="text/css">
				11	</head>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	12
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	13	<body>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	14
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	15	<div class="doc_title"> LLVM Language Reference Manual </div>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	16	<ol>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	17	<li><a href="#abstract">Abstract</a></li>
				18	<li><a href="#introduction">Introduction</a></li>
				19	<li><a href="#identifiers">Identifiers</a></li>
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	20	<li><a href="#highlevel">High Level Structure</a>
				21	<ol>
				22	<li><a href="#modulestructure">Module Structure</a></li>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	23	<li><a href="#linkage">Linkage Types</a></li>
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	24	<li><a href="#callingconv">Calling Conventions</a></li>
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	25	<li><a href="#globalvars">Global Variables</a></li>
Chris Lattner	91c15c4	2006-01-23 23:23:47 +0000	[diff] [blame]	26	<li><a href="#functionstructure">Functions</a></li>
Anton Korobeynikov	546ea7e	2007-04-29 18:02:48 +0000	[diff] [blame]	27	<li><a href="#aliasstructure">Aliases</a>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	28	<li><a href="#paramattrs">Parameter Attributes</a></li>
Devang Patel	9eb525d	2008-09-26 23:51:19 +0000	[diff] [blame]	29	<li><a href="#fnattrs">Function Attributes</a></li>
Gordon Henriksen	71183b6	2007-12-10 03:18:06 +0000	[diff] [blame]	30	<li><a href="#gc">Garbage Collector Names</a></li>
Chris Lattner	91c15c4	2006-01-23 23:23:47 +0000	[diff] [blame]	31	<li><a href="#moduleasm">Module-Level Inline Assembly</a></li>
Reid Spencer	50c723a	2007-02-19 23:54:10 +0000	[diff] [blame]	32	<li><a href="#datalayout">Data Layout</a></li>
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	33	</ol>
				34	</li>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	35	<li><a href="#typesystem">Type System</a>
				36	<ol>
Chris Lattner	7824d18	2008-01-04 04:32:38 +0000	[diff] [blame]	37	<li><a href="#t_classifications">Type Classifications</a></li>
Robert Bocchino	820bc75b	2006-02-17 21:18:08 +0000	[diff] [blame]	38	<li><a href="#t_primitive">Primitive Types</a>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	39	<ol>
Chris Lattner	7824d18	2008-01-04 04:32:38 +0000	[diff] [blame]	40	<li><a href="#t_floating">Floating Point Types</a></li>
				41	<li><a href="#t_void">Void Type</a></li>
				42	<li><a href="#t_label">Label Type</a></li>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	43	</ol>
				44	</li>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	45	<li><a href="#t_derived">Derived Types</a>
				46	<ol>
Chris Lattner	9a2e3cb	2007-12-18 06:18:21 +0000	[diff] [blame]	47	<li><a href="#t_integer">Integer Type</a></li>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	48	<li><a href="#t_array">Array Type</a></li>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	49	<li><a href="#t_function">Function Type</a></li>
				50	<li><a href="#t_pointer">Pointer Type</a></li>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	51	<li><a href="#t_struct">Structure Type</a></li>
Andrew Lenharth	8df88e2	2006-12-08 17:13:00 +0000	[diff] [blame]	52	<li><a href="#t_pstruct">Packed Structure Type</a></li>
Reid Spencer	404a325	2007-02-15 03:07:05 +0000	[diff] [blame]	53	<li><a href="#t_vector">Vector Type</a></li>
Chris Lattner	37b6b09	2005-04-25 17:34:15 +0000	[diff] [blame]	54	<li><a href="#t_opaque">Opaque Type</a></li>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	55	</ol>
				56	</li>
				57	</ol>
				58	</li>
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	59	<li><a href="#constants">Constants</a>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	60	<ol>
				61	<li><a href="#simpleconstants">Simple Constants</a>
				62	<li><a href="#aggregateconstants">Aggregate Constants</a>
				63	<li><a href="#globalconstants">Global Variable and Function Addresses</a>
				64	<li><a href="#undefvalues">Undefined Values</a>
				65	<li><a href="#constantexprs">Constant Expressions</a>
				66	</ol>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	67	</li>
Chris Lattner	98f013c	2006-01-25 23:47:57 +0000	[diff] [blame]	68	<li><a href="#othervalues">Other Values</a>
				69	<ol>
				70	<li><a href="#inlineasm">Inline Assembler Expressions</a>
				71	</ol>
				72	</li>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	73	<li><a href="#instref">Instruction Reference</a>
				74	<ol>
				75	<li><a href="#terminators">Terminator Instructions</a>
				76	<ol>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	77	<li><a href="#i_ret">'<tt>ret</tt>' Instruction</a></li>
				78	<li><a href="#i_br">'<tt>br</tt>' Instruction</a></li>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	79	<li><a href="#i_switch">'<tt>switch</tt>' Instruction</a></li>
				80	<li><a href="#i_invoke">'<tt>invoke</tt>' Instruction</a></li>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	81	<li><a href="#i_unwind">'<tt>unwind</tt>' Instruction</a></li>
Chris Lattner	08b7d5b	2004-10-16 18:04:13 +0000	[diff] [blame]	82	<li><a href="#i_unreachable">'<tt>unreachable</tt>' Instruction</a></li>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	83	</ol>
				84	</li>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	85	<li><a href="#binaryops">Binary Operations</a>
				86	<ol>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	87	<li><a href="#i_add">'<tt>add</tt>' Instruction</a></li>
				88	<li><a href="#i_sub">'<tt>sub</tt>' Instruction</a></li>
				89	<li><a href="#i_mul">'<tt>mul</tt>' Instruction</a></li>
Reid Spencer	7e80b0b	2006-10-26 06:15:43 +0000	[diff] [blame]	90	<li><a href="#i_udiv">'<tt>udiv</tt>' Instruction</a></li>
				91	<li><a href="#i_sdiv">'<tt>sdiv</tt>' Instruction</a></li>
				92	<li><a href="#i_fdiv">'<tt>fdiv</tt>' Instruction</a></li>
Reid Spencer	7eb55b3	2006-11-02 01:53:59 +0000	[diff] [blame]	93	<li><a href="#i_urem">'<tt>urem</tt>' Instruction</a></li>
				94	<li><a href="#i_srem">'<tt>srem</tt>' Instruction</a></li>
				95	<li><a href="#i_frem">'<tt>frem</tt>' Instruction</a></li>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	96	</ol>
				97	</li>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	98	<li><a href="#bitwiseops">Bitwise Binary Operations</a>
				99	<ol>
Reid Spencer	2ab0193	2007-02-02 13:57:07 +0000	[diff] [blame]	100	<li><a href="#i_shl">'<tt>shl</tt>' Instruction</a></li>
				101	<li><a href="#i_lshr">'<tt>lshr</tt>' Instruction</a></li>
				102	<li><a href="#i_ashr">'<tt>ashr</tt>' Instruction</a></li>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	103	<li><a href="#i_and">'<tt>and</tt>' Instruction</a></li>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	104	<li><a href="#i_or">'<tt>or</tt>' Instruction</a></li>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	105	<li><a href="#i_xor">'<tt>xor</tt>' Instruction</a></li>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	106	</ol>
				107	</li>
Chris Lattner	ce83bff	2006-04-08 23:07:04 +0000	[diff] [blame]	108	<li><a href="#vectorops">Vector Operations</a>
				109	<ol>
				110	<li><a href="#i_extractelement">'<tt>extractelement</tt>' Instruction</a></li>
				111	<li><a href="#i_insertelement">'<tt>insertelement</tt>' Instruction</a></li>
				112	<li><a href="#i_shufflevector">'<tt>shufflevector</tt>' Instruction</a></li>
Chris Lattner	ce83bff	2006-04-08 23:07:04 +0000	[diff] [blame]	113	</ol>
				114	</li>
Dan Gohman	b9d6660	2008-05-12 23:51:09 +0000	[diff] [blame]	115	<li><a href="#aggregateops">Aggregate Operations</a>
				116	<ol>
				117	<li><a href="#i_extractvalue">'<tt>extractvalue</tt>' Instruction</a></li>
				118	<li><a href="#i_insertvalue">'<tt>insertvalue</tt>' Instruction</a></li>
				119	</ol>
				120	</li>
Chris Lattner	6ab6672	2006-08-15 00:45:58 +0000	[diff] [blame]	121	<li><a href="#memoryops">Memory Access and Addressing Operations</a>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	122	<ol>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	123	<li><a href="#i_malloc">'<tt>malloc</tt>' Instruction</a></li>
				124	<li><a href="#i_free">'<tt>free</tt>' Instruction</a></li>
				125	<li><a href="#i_alloca">'<tt>alloca</tt>' Instruction</a></li>
Robert Bocchino	820bc75b	2006-02-17 21:18:08 +0000	[diff] [blame]	126	<li><a href="#i_load">'<tt>load</tt>' Instruction</a></li>
				127	<li><a href="#i_store">'<tt>store</tt>' Instruction</a></li>
				128	<li><a href="#i_getelementptr">'<tt>getelementptr</tt>' Instruction</a></li>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	129	</ol>
				130	</li>
Reid Spencer	97c5fa4	2006-11-08 01:18:52 +0000	[diff] [blame]	131	<li><a href="#convertops">Conversion Operations</a>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	132	<ol>
				133	<li><a href="#i_trunc">'<tt>trunc .. to</tt>' Instruction</a></li>
				134	<li><a href="#i_zext">'<tt>zext .. to</tt>' Instruction</a></li>
				135	<li><a href="#i_sext">'<tt>sext .. to</tt>' Instruction</a></li>
				136	<li><a href="#i_fptrunc">'<tt>fptrunc .. to</tt>' Instruction</a></li>
				137	<li><a href="#i_fpext">'<tt>fpext .. to</tt>' Instruction</a></li>
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	138	<li><a href="#i_fptoui">'<tt>fptoui .. to</tt>' Instruction</a></li>
				139	<li><a href="#i_fptosi">'<tt>fptosi .. to</tt>' Instruction</a></li>
				140	<li><a href="#i_uitofp">'<tt>uitofp .. to</tt>' Instruction</a></li>
				141	<li><a href="#i_sitofp">'<tt>sitofp .. to</tt>' Instruction</a></li>
Reid Spencer	b7344ff	2006-11-11 21:00:47 +0000	[diff] [blame]	142	<li><a href="#i_ptrtoint">'<tt>ptrtoint .. to</tt>' Instruction</a></li>
				143	<li><a href="#i_inttoptr">'<tt>inttoptr .. to</tt>' Instruction</a></li>
Reid Spencer	5b95064	2006-11-11 23:08:07 +0000	[diff] [blame]	144	<li><a href="#i_bitcast">'<tt>bitcast .. to</tt>' Instruction</a></li>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	145	</ol>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	146	<li><a href="#otherops">Other Operations</a>
				147	<ol>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	148	<li><a href="#i_icmp">'<tt>icmp</tt>' Instruction</a></li>
				149	<li><a href="#i_fcmp">'<tt>fcmp</tt>' Instruction</a></li>
Nate Begeman	d219570	2008-05-12 19:01:56 +0000	[diff] [blame]	150	<li><a href="#i_vicmp">'<tt>vicmp</tt>' Instruction</a></li>
				151	<li><a href="#i_vfcmp">'<tt>vfcmp</tt>' Instruction</a></li>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	152	<li><a href="#i_phi">'<tt>phi</tt>' Instruction</a></li>
Chris Lattner	b53c28d	2004-03-12 05:50:16 +0000	[diff] [blame]	153	<li><a href="#i_select">'<tt>select</tt>' Instruction</a></li>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	154	<li><a href="#i_call">'<tt>call</tt>' Instruction</a></li>
Chris Lattner	3333747	2006-01-13 23:26:01 +0000	[diff] [blame]	155	<li><a href="#i_va_arg">'<tt>va_arg</tt>' Instruction</a></li>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	156	</ol>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	157	</li>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	158	</ol>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	159	</li>
Chris Lattner	bd64b4e	2003-05-08 04:57:36 +0000	[diff] [blame]	160	<li><a href="#intrinsics">Intrinsic Functions</a>
Chris Lattner	bd64b4e	2003-05-08 04:57:36 +0000	[diff] [blame]	161	<ol>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	162	<li><a href="#int_varargs">Variable Argument Handling Intrinsics</a>
				163	<ol>
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	164	<li><a href="#int_va_start">'<tt>llvm.va_start</tt>' Intrinsic</a></li>
				165	<li><a href="#int_va_end">'<tt>llvm.va_end</tt>' Intrinsic</a></li>
				166	<li><a href="#int_va_copy">'<tt>llvm.va_copy</tt>' Intrinsic</a></li>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	167	</ol>
				168	</li>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	169	<li><a href="#int_gc">Accurate Garbage Collection Intrinsics</a>
				170	<ol>
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	171	<li><a href="#int_gcroot">'<tt>llvm.gcroot</tt>' Intrinsic</a></li>
				172	<li><a href="#int_gcread">'<tt>llvm.gcread</tt>' Intrinsic</a></li>
				173	<li><a href="#int_gcwrite">'<tt>llvm.gcwrite</tt>' Intrinsic</a></li>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	174	</ol>
				175	</li>
Chris Lattner	3649c3a	2004-02-14 04:08:35 +0000	[diff] [blame]	176	<li><a href="#int_codegen">Code Generator Intrinsics</a>
				177	<ol>
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	178	<li><a href="#int_returnaddress">'<tt>llvm.returnaddress</tt>' Intrinsic</a></li>
				179	<li><a href="#int_frameaddress">'<tt>llvm.frameaddress</tt>' Intrinsic</a></li>
				180	<li><a href="#int_stacksave">'<tt>llvm.stacksave</tt>' Intrinsic</a></li>
				181	<li><a href="#int_stackrestore">'<tt>llvm.stackrestore</tt>' Intrinsic</a></li>
				182	<li><a href="#int_prefetch">'<tt>llvm.prefetch</tt>' Intrinsic</a></li>
				183	<li><a href="#int_pcmarker">'<tt>llvm.pcmarker</tt>' Intrinsic</a></li>
				184	<li><a href="#int_readcyclecounter"><tt>llvm.readcyclecounter</tt>' Intrinsic</a></li>
John Criswell	aa1c3c1	2004-04-09 16:43:20 +0000	[diff] [blame]	185	</ol>
				186	</li>
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	187	<li><a href="#int_libc">Standard C Library Intrinsics</a>
				188	<ol>
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	189	<li><a href="#int_memcpy">'<tt>llvm.memcpy.*</tt>' Intrinsic</a></li>
				190	<li><a href="#int_memmove">'<tt>llvm.memmove.*</tt>' Intrinsic</a></li>
				191	<li><a href="#int_memset">'<tt>llvm.memset.*</tt>' Intrinsic</a></li>
				192	<li><a href="#int_sqrt">'<tt>llvm.sqrt.*</tt>' Intrinsic</a></li>
				193	<li><a href="#int_powi">'<tt>llvm.powi.*</tt>' Intrinsic</a></li>
Dan Gohman	b6324c1	2007-10-15 20:30:11 +0000	[diff] [blame]	194	<li><a href="#int_sin">'<tt>llvm.sin.*</tt>' Intrinsic</a></li>
				195	<li><a href="#int_cos">'<tt>llvm.cos.*</tt>' Intrinsic</a></li>
				196	<li><a href="#int_pow">'<tt>llvm.pow.*</tt>' Intrinsic</a></li>
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	197	</ol>
				198	</li>
Nate Begeman	0f223bb	2006-01-13 23:26:38 +0000	[diff] [blame]	199	<li><a href="#int_manip">Bit Manipulation Intrinsics</a>
Andrew Lenharth	1d46352	2005-05-03 18:01:48 +0000	[diff] [blame]	200	<ol>
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	201	<li><a href="#int_bswap">'<tt>llvm.bswap.*</tt>' Intrinsics</a></li>
Chris Lattner	b748c67	2006-01-16 22:34:14 +0000	[diff] [blame]	202	<li><a href="#int_ctpop">'<tt>llvm.ctpop.*</tt>' Intrinsic </a></li>
				203	<li><a href="#int_ctlz">'<tt>llvm.ctlz.*</tt>' Intrinsic </a></li>
				204	<li><a href="#int_cttz">'<tt>llvm.cttz.*</tt>' Intrinsic </a></li>
Reid Spencer	5bf54c8	2007-04-11 23:23:49 +0000	[diff] [blame]	205	<li><a href="#int_part_select">'<tt>llvm.part.select.*</tt>' Intrinsic </a></li>
				206	<li><a href="#int_part_set">'<tt>llvm.part.set.*</tt>' Intrinsic </a></li>
Andrew Lenharth	1d46352	2005-05-03 18:01:48 +0000	[diff] [blame]	207	</ol>
				208	</li>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	209	<li><a href="#int_debugger">Debugger intrinsics</a></li>
Jim Laskey	2211f49	2007-03-14 19:31:19 +0000	[diff] [blame]	210	<li><a href="#int_eh">Exception Handling intrinsics</a></li>
Duncan Sands	86e0119	2007-09-11 14:10:23 +0000	[diff] [blame]	211	<li><a href="#int_trampoline">Trampoline Intrinsic</a>
Duncan Sands	644f917	2007-07-27 12:58:54 +0000	[diff] [blame]	212	<ol>
				213	<li><a href="#int_it">'<tt>llvm.init.trampoline</tt>' Intrinsic</a></li>
Duncan Sands	644f917	2007-07-27 12:58:54 +0000	[diff] [blame]	214	</ol>
				215	</li>
Andrew Lenharth	9b254ee	2008-02-16 01:24:58 +0000	[diff] [blame]	216	<li><a href="#int_atomics">Atomic intrinsics</a>
				217	<ol>
Andrew Lenharth	9552894	2008-02-21 06:45:13 +0000	[diff] [blame]	218	<li><a href="#int_memory_barrier"><tt>llvm.memory_barrier</tt></a></li>
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	219	<li><a href="#int_atomic_cmp_swap"><tt>llvm.atomic.cmp.swap</tt></a></li>
Andrew Lenharth	9552894	2008-02-21 06:45:13 +0000	[diff] [blame]	220	<li><a href="#int_atomic_swap"><tt>llvm.atomic.swap</tt></a></li>
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	221	<li><a href="#int_atomic_load_add"><tt>llvm.atomic.load.add</tt></a></li>
				222	<li><a href="#int_atomic_load_sub"><tt>llvm.atomic.load.sub</tt></a></li>
				223	<li><a href="#int_atomic_load_and"><tt>llvm.atomic.load.and</tt></a></li>
				224	<li><a href="#int_atomic_load_nand"><tt>llvm.atomic.load.nand</tt></a></li>
				225	<li><a href="#int_atomic_load_or"><tt>llvm.atomic.load.or</tt></a></li>
				226	<li><a href="#int_atomic_load_xor"><tt>llvm.atomic.load.xor</tt></a></li>
				227	<li><a href="#int_atomic_load_max"><tt>llvm.atomic.load.max</tt></a></li>
				228	<li><a href="#int_atomic_load_min"><tt>llvm.atomic.load.min</tt></a></li>
				229	<li><a href="#int_atomic_load_umax"><tt>llvm.atomic.load.umax</tt></a></li>
				230	<li><a href="#int_atomic_load_umin"><tt>llvm.atomic.load.umin</tt></a></li>
Andrew Lenharth	9b254ee	2008-02-16 01:24:58 +0000	[diff] [blame]	231	</ol>
				232	</li>
Reid Spencer	5b2cb0f	2007-07-20 19:59:11 +0000	[diff] [blame]	233	<li><a href="#int_general">General intrinsics</a>
Tanya Lattner	cb1b960	2007-06-15 20:50:54 +0000	[diff] [blame]	234	<ol>
Reid Spencer	5b2cb0f	2007-07-20 19:59:11 +0000	[diff] [blame]	235	<li><a href="#int_var_annotation">
Tanya Lattner	08abc81	2007-09-22 00:01:26 +0000	[diff] [blame]	236	<tt>llvm.var.annotation</tt>' Intrinsic</a></li>
Tanya Lattner	293c037	2007-09-21 22:59:12 +0000	[diff] [blame]	237	<li><a href="#int_annotation">
Tanya Lattner	08abc81	2007-09-22 00:01:26 +0000	[diff] [blame]	238	<tt>llvm.annotation.*</tt>' Intrinsic</a></li>
Anton Korobeynikov	06cbb65	2008-01-15 22:31:34 +0000	[diff] [blame]	239	<li><a href="#int_trap">
				240	<tt>llvm.trap</tt>' Intrinsic</a></li>
Tanya Lattner	293c037	2007-09-21 22:59:12 +0000	[diff] [blame]	241	</ol>
Tanya Lattner	cb1b960	2007-06-15 20:50:54 +0000	[diff] [blame]	242	</li>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	243	</ol>
				244	</li>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	245	</ol>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	246
				247	<div class="doc_author">
				248	<p>Written by <a href="mailto:sabre@nondot.org">Chris Lattner</a>
				249	and <a href="mailto:vadve@cs.uiuc.edu">Vikram Adve</a></p>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	250	</div>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	251
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	252	<!-- *********************************************************************** -->
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	253	<div class="doc_section"> <a name="abstract">Abstract </a></div>
				254	<!-- *********************************************************************** -->
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	255
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	256	<div class="doc_text">
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	257	<p>This document is a reference manual for the LLVM assembly language.
Bill Wendling	6e03f9a	2008-08-05 22:29:16 +0000	[diff] [blame]	258	LLVM is a Static Single Assignment (SSA) based representation that provides
Chris Lattner	67c37d1	2008-08-05 18:29:16 +0000	[diff] [blame]	259	type safety, low-level operations, flexibility, and the capability of
				260	representing 'all' high-level languages cleanly. It is the common code
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	261	representation used throughout all phases of the LLVM compilation
				262	strategy.</p>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	263	</div>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	264
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	265	<!-- *********************************************************************** -->
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	266	<div class="doc_section"> <a name="introduction">Introduction</a> </div>
				267	<!-- *********************************************************************** -->
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	268
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	269	<div class="doc_text">
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	270
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	271	<p>The LLVM code representation is designed to be used in three
Gabor Greif	a54634a	2007-07-06 22:07:22 +0000	[diff] [blame]	272	different forms: as an in-memory compiler IR, as an on-disk bitcode
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	273	representation (suitable for fast loading by a Just-In-Time compiler),
				274	and as a human readable assembly language representation. This allows
				275	LLVM to provide a powerful intermediate representation for efficient
				276	compiler transformations and analysis, while providing a natural means
				277	to debug and visualize the transformations. The three different forms
				278	of LLVM are all equivalent. This document describes the human readable
				279	representation and notation.</p>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	280
John Criswell	4a3327e	2005-05-13 22:25:59 +0000	[diff] [blame]	281	<p>The LLVM representation aims to be light-weight and low-level
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	282	while being expressive, typed, and extensible at the same time. It
				283	aims to be a "universal IR" of sorts, by being at a low enough level
				284	that high-level ideas may be cleanly mapped to it (similar to how
				285	microprocessors are "universal IR's", allowing many source languages to
				286	be mapped to them). By providing type information, LLVM can be used as
				287	the target of optimizations: for example, through pointer analysis, it
				288	can be proven that a C automatic variable is never accessed outside of
				289	the current function... allowing it to be promoted to a simple SSA
				290	value instead of a memory location.</p>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	291
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	292	</div>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	293
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	294	<!-- _______________________________________________________________________ -->
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	295	<div class="doc_subsubsection"> <a name="wellformed">Well-Formedness</a> </div>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	296
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	297	<div class="doc_text">
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	298
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	299	<p>It is important to note that this document describes 'well formed'
				300	LLVM assembly language. There is a difference between what the parser
				301	accepts and what is considered 'well formed'. For example, the
				302	following instruction is syntactically okay, but not well formed:</p>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	303
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	304	<div class="doc_code">
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	305	<pre>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	306	%x = <a href="#i_add">add</a> i32 1, %x
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	307	</pre>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	308	</div>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	309
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	310	<p>...because the definition of <tt>%x</tt> does not dominate all of
				311	its uses. The LLVM infrastructure provides a verification pass that may
				312	be used to verify that an LLVM module is well formed. This pass is
John Criswell	4a3327e	2005-05-13 22:25:59 +0000	[diff] [blame]	313	automatically run by the parser after parsing input assembly and by
Gabor Greif	a54634a	2007-07-06 22:07:22 +0000	[diff] [blame]	314	the optimizer before it outputs bitcode. The violations pointed out
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	315	by the verifier pass indicate bugs in transformation passes or input to
				316	the parser.</p>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	317	</div>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	318
Chris Lattner	87a3dbe	2007-10-03 17:34:29 +0000	[diff] [blame]	319	<!-- Describe the typesetting conventions here. -->
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	320
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	321	<!-- *********************************************************************** -->
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	322	<div class="doc_section"> <a name="identifiers">Identifiers</a> </div>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	323	<!-- *********************************************************************** -->
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	324
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	325	<div class="doc_text">
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	326
Reid Spencer	b23b65f	2007-08-07 14:34:28 +0000	[diff] [blame]	327	<p>LLVM identifiers come in two basic types: global and local. Global
				328	identifiers (functions, global variables) begin with the @ character. Local
				329	identifiers (register names, types) begin with the % character. Additionally,
				330	there are three different formats for identifiers, for different purposes:
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	331
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	332	<ol>
Reid Spencer	b23b65f	2007-08-07 14:34:28 +0000	[diff] [blame]	333	<li>Named values are represented as a string of characters with their prefix.
				334	For example, %foo, @DivisionByZero, %a.really.long.identifier. The actual
				335	regular expression used is '<tt>[%@][a-zA-Z$._][a-zA-Z$._0-9]*</tt>'.
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	336	Identifiers which require other characters in their names can be surrounded
Reid Spencer	b23b65f	2007-08-07 14:34:28 +0000	[diff] [blame]	337	with quotes. In this way, anything except a <tt>"</tt> character can
				338	be used in a named value.</li>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	339
Reid Spencer	b23b65f	2007-08-07 14:34:28 +0000	[diff] [blame]	340	<li>Unnamed values are represented as an unsigned numeric value with their
				341	prefix. For example, %12, @2, %44.</li>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	342
Reid Spencer	8f08d80	2004-12-09 18:02:53 +0000	[diff] [blame]	343	<li>Constants, which are described in a <a href="#constants">section about
				344	constants</a>, below.</li>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	345	</ol>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	346
Reid Spencer	b23b65f	2007-08-07 14:34:28 +0000	[diff] [blame]	347	<p>LLVM requires that values start with a prefix for two reasons: Compilers
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	348	don't need to worry about name clashes with reserved words, and the set of
				349	reserved words may be expanded in the future without penalty. Additionally,
				350	unnamed identifiers allow a compiler to quickly come up with a temporary
				351	variable without having to avoid symbol table conflicts.</p>
				352
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	353	<p>Reserved words in LLVM are very similar to reserved words in other
Reid Spencer	5b95064	2006-11-11 23:08:07 +0000	[diff] [blame]	354	languages. There are keywords for different opcodes
				355	('<tt><a href="#i_add">add</a></tt>',
				356	'<tt><a href="#i_bitcast">bitcast</a></tt>',
				357	'<tt><a href="#i_ret">ret</a></tt>', etc...), for primitive type names ('<tt><a
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	358	href="#t_void">void</a></tt>', '<tt><a href="#t_primitive">i32</a></tt>', etc...),
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	359	and others. These reserved words cannot conflict with variable names, because
Reid Spencer	b23b65f	2007-08-07 14:34:28 +0000	[diff] [blame]	360	none of them start with a prefix character ('%' or '@').</p>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	361
				362	<p>Here is an example of LLVM code to multiply the integer variable
				363	'<tt>%X</tt>' by 8:</p>
				364
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	365	<p>The easy way:</p>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	366
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	367	<div class="doc_code">
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	368	<pre>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	369	%result = <a href="#i_mul">mul</a> i32 %X, 8
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	370	</pre>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	371	</div>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	372
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	373	<p>After strength reduction:</p>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	374
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	375	<div class="doc_code">
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	376	<pre>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	377	%result = <a href="#i_shl">shl</a> i32 %X, i8 3
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	378	</pre>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	379	</div>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	380
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	381	<p>And the hard way:</p>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	382
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	383	<div class="doc_code">
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	384	<pre>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	385	<a href="#i_add">add</a> i32 %X, %X <i>; yields {i32}:%0</i>
				386	<a href="#i_add">add</a> i32 %0, %0 <i>; yields {i32}:%1</i>
				387	%result = <a href="#i_add">add</a> i32 %1, %1
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	388	</pre>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	389	</div>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	390
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	391	<p>This last way of multiplying <tt>%X</tt> by 8 illustrates several
				392	important lexical features of LLVM:</p>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	393
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	394	<ol>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	395
				396	<li>Comments are delimited with a '<tt>;</tt>' and go until the end of
				397	line.</li>
				398
				399	<li>Unnamed temporaries are created when the result of a computation is not
				400	assigned to a named value.</li>
				401
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	402	<li>Unnamed temporaries are numbered sequentially</li>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	403
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	404	</ol>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	405
John Criswell	02fdc6f	2005-05-12 16:52:32 +0000	[diff] [blame]	406	<p>...and it also shows a convention that we follow in this document. When
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	407	demonstrating instructions, we will follow an instruction with a comment that
				408	defines the type and name of value produced. Comments are shown in italic
				409	text.</p>
				410
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	411	</div>
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	412
				413	<!-- *********************************************************************** -->
				414	<div class="doc_section"> <a name="highlevel">High Level Structure</a> </div>
				415	<!-- *********************************************************************** -->
				416
				417	<!-- ======================================================================= -->
				418	<div class="doc_subsection"> <a name="modulestructure">Module Structure</a>
				419	</div>
				420
				421	<div class="doc_text">
				422
				423	<p>LLVM programs are composed of "Module"s, each of which is a
				424	translation unit of the input programs. Each module consists of
				425	functions, global variables, and symbol table entries. Modules may be
				426	combined together with the LLVM linker, which merges function (and
				427	global variable) definitions, resolves forward declarations, and merges
				428	symbol table entries. Here is an example of the "hello world" module:</p>
				429
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	430	<div class="doc_code">
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	431	<pre><i>; Declare the string constant as a global constant...</i>
Chris Lattner	2b0bf4f	2007-06-12 17:00:26 +0000	[diff] [blame]	432	<a href="#identifiers">@.LC0</a> = <a href="#linkage_internal">internal</a> <a
				433	href="#globalvars">constant</a> <a href="#t_array">[13 x i8]</a> c"hello world\0A\00" <i>; [13 x i8]*</i>
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	434
				435	<i>; External declaration of the puts function</i>
Chris Lattner	2b0bf4f	2007-06-12 17:00:26 +0000	[diff] [blame]	436	<a href="#functionstructure">declare</a> i32 @puts(i8 ) <i>; i32(i8 )* </i>
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	437
				438	<i>; Definition of main function</i>
Chris Lattner	2b0bf4f	2007-06-12 17:00:26 +0000	[diff] [blame]	439	define i32 @main() { <i>; i32()* </i>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	440	<i>; Convert [13x i8 ]* to i8 *...</i>
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	441	%cast210 = <a
Chris Lattner	2150cde	2007-06-12 17:01:15 +0000	[diff] [blame]	442	href="#i_getelementptr">getelementptr</a> [13 x i8 ]* @.LC0, i64 0, i64 0 <i>; i8 *</i>
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	443
				444	<i>; Call puts function to write out the string to stdout...</i>
				445	<a
Chris Lattner	2b0bf4f	2007-06-12 17:00:26 +0000	[diff] [blame]	446	href="#i_call">call</a> i32 @puts(i8 * %cast210) <i>; i32</i>
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	447	<a
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	448	href="#i_ret">ret</a> i32 0<br>}<br>
				449	</pre>
				450	</div>
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	451
				452	<p>This example is made up of a <a href="#globalvars">global variable</a>
				453	named "<tt>.LC0</tt>", an external declaration of the "<tt>puts</tt>"
				454	function, and a <a href="#functionstructure">function definition</a>
				455	for "<tt>main</tt>".</p>
				456
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	457	<p>In general, a module is made up of a list of global values,
				458	where both functions and global variables are global values. Global values are
				459	represented by a pointer to a memory location (in this case, a pointer to an
				460	array of char, and a pointer to a function), and have one of the following <a
				461	href="#linkage">linkage types</a>.</p>
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	462
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	463	</div>
				464
				465	<!-- ======================================================================= -->
				466	<div class="doc_subsection">
				467	<a name="linkage">Linkage Types</a>
				468	</div>
				469
				470	<div class="doc_text">
				471
				472	<p>
				473	All Global Variables and Functions have one of the following types of linkage:
				474	</p>
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	475
				476	<dl>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	477
Dale Johannesen	4188aad	2008-05-23 23:13:41 +0000	[diff] [blame]	478	<dt><tt><b><a name="linkage_internal">internal</a></b></tt>: </dt>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	479
				480	<dd>Global values with internal linkage are only directly accessible by
				481	objects in the current module. In particular, linking code into a module with
				482	an internal global value may cause the internal to be renamed as necessary to
				483	avoid collisions. Because the symbol is internal to the module, all
				484	references can be updated. This corresponds to the notion of the
Chris Lattner	e20b470	2007-01-14 06:51:48 +0000	[diff] [blame]	485	'<tt>static</tt>' keyword in C.
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	486	</dd>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	487
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	488	<dt><tt><b><a name="linkage_linkonce">linkonce</a></b></tt>: </dt>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	489
Chris Lattner	e20b470	2007-01-14 06:51:48 +0000	[diff] [blame]	490	<dd>Globals with "<tt>linkonce</tt>" linkage are merged with other globals of
				491	the same name when linkage occurs. This is typically used to implement
				492	inline functions, templates, or other code which must be generated in each
				493	translation unit that uses it. Unreferenced <tt>linkonce</tt> globals are
				494	allowed to be discarded.
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	495	</dd>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	496
Dale Johannesen	4188aad	2008-05-23 23:13:41 +0000	[diff] [blame]	497	<dt><tt><b><a name="linkage_common">common</a></b></tt>: </dt>
				498
				499	<dd>"<tt>common</tt>" linkage is exactly the same as <tt>linkonce</tt>
				500	linkage, except that unreferenced <tt>common</tt> globals may not be
				501	discarded. This is used for globals that may be emitted in multiple
				502	translation units, but that are not guaranteed to be emitted into every
				503	translation unit that uses them. One example of this is tentative
				504	definitions in C, such as "<tt>int X;</tt>" at global scope.
				505	</dd>
				506
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	507	<dt><tt><b><a name="linkage_weak">weak</a></b></tt>: </dt>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	508
Dale Johannesen	4188aad	2008-05-23 23:13:41 +0000	[diff] [blame]	509	<dd>"<tt>weak</tt>" linkage is the same as <tt>common</tt> linkage, except
				510	that some targets may choose to emit different assembly sequences for them
				511	for target-dependent reasons. This is used for globals that are declared
				512	"weak" in C source code.
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	513	</dd>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	514
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	515	<dt><tt><b><a name="linkage_appending">appending</a></b></tt>: </dt>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	516
				517	<dd>"<tt>appending</tt>" linkage may only be applied to global variables of
				518	pointer to array type. When two global variables with appending linkage are
				519	linked together, the two global arrays are appended together. This is the
				520	LLVM, typesafe, equivalent of having the system linker append together
				521	"sections" with identical names when .o files are linked.
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	522	</dd>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	523
Anton Korobeynikov	a0554d9	2007-01-12 19:20:47 +0000	[diff] [blame]	524	<dt><tt><b><a name="linkage_externweak">extern_weak</a></b></tt>: </dt>
Chris Lattner	67c37d1	2008-08-05 18:29:16 +0000	[diff] [blame]	525	<dd>The semantics of this linkage follow the ELF object file model: the
				526	symbol is weak until linked, if not linked, the symbol becomes null instead
				527	of being an undefined reference.
Anton Korobeynikov	a0554d9	2007-01-12 19:20:47 +0000	[diff] [blame]	528	</dd>
Anton Korobeynikov	a0554d9	2007-01-12 19:20:47 +0000	[diff] [blame]	529
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	530	<dt><tt><b><a name="linkage_external">externally visible</a></b></tt>:</dt>
Chris Lattner	d79749a	2004-12-09 16:36:40 +0000	[diff] [blame]	531
				532	<dd>If none of the above identifiers are used, the global is externally
				533	visible, meaning that it participates in linkage and can be used to resolve
				534	external symbol references.
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	535	</dd>
Reid Spencer	7972c47	2007-04-11 23:49:50 +0000	[diff] [blame]	536	</dl>
Anton Korobeynikov	d61d39e	2006-09-14 18:23:27 +0000	[diff] [blame]	537
Anton Korobeynikov	d61d39e	2006-09-14 18:23:27 +0000	[diff] [blame]	538	<p>
				539	The next two types of linkage are targeted for Microsoft Windows platform
				540	only. They are designed to support importing (exporting) symbols from (to)
Chris Lattner	67c37d1	2008-08-05 18:29:16 +0000	[diff] [blame]	541	DLLs (Dynamic Link Libraries).
Anton Korobeynikov	d61d39e	2006-09-14 18:23:27 +0000	[diff] [blame]	542	</p>
				543
Anton Korobeynikov	a0554d9	2007-01-12 19:20:47 +0000	[diff] [blame]	544	<dl>
Anton Korobeynikov	d61d39e	2006-09-14 18:23:27 +0000	[diff] [blame]	545	<dt><tt><b><a name="linkage_dllimport">dllimport</a></b></tt>: </dt>
				546
				547	<dd>"<tt>dllimport</tt>" linkage causes the compiler to reference a function
				548	or variable via a global pointer to a pointer that is set up by the DLL
				549	exporting the symbol. On Microsoft Windows targets, the pointer name is
				550	formed by combining <code>_imp__</code> and the function or variable name.
				551	</dd>
				552
				553	<dt><tt><b><a name="linkage_dllexport">dllexport</a></b></tt>: </dt>
				554
				555	<dd>"<tt>dllexport</tt>" linkage causes the compiler to provide a global
				556	pointer to a pointer in a DLL, so that it can be referenced with the
				557	<tt>dllimport</tt> attribute. On Microsoft Windows targets, the pointer
				558	name is formed by combining <code>_imp__</code> and the function or variable
				559	name.
				560	</dd>
				561
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	562	</dl>
				563
Anton Korobeynikov	a0554d9	2007-01-12 19:20:47 +0000	[diff] [blame]	564	<p><a name="linkage_external"></a>For example, since the "<tt>.LC0</tt>"
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	565	variable is defined to be internal, if another module defined a "<tt>.LC0</tt>"
				566	variable and was linked with this one, one of the two would be renamed,
				567	preventing a collision. Since "<tt>main</tt>" and "<tt>puts</tt>" are
				568	external (i.e., lacking any linkage declarations), they are accessible
Reid Spencer	92c671e	2007-01-05 00:59:10 +0000	[diff] [blame]	569	outside of the current module.</p>
				570	<p>It is illegal for a function <i>declaration</i>
				571	to have any linkage type other than "externally visible", <tt>dllimport</tt>,
Anton Korobeynikov	a0554d9	2007-01-12 19:20:47 +0000	[diff] [blame]	572	or <tt>extern_weak</tt>.</p>
Anton Korobeynikov	a97b694	2007-04-25 14:27:10 +0000	[diff] [blame]	573	<p>Aliases can have only <tt>external</tt>, <tt>internal</tt> and <tt>weak</tt>
				574	linkages.
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	575	</div>
				576
				577	<!-- ======================================================================= -->
				578	<div class="doc_subsection">
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	579	<a name="callingconv">Calling Conventions</a>
				580	</div>
				581
				582	<div class="doc_text">
				583
				584	<p>LLVM <a href="#functionstructure">functions</a>, <a href="#i_call">calls</a>
				585	and <a href="#i_invoke">invokes</a> can all have an optional calling convention
				586	specified for the call. The calling convention of any pair of dynamic
				587	caller/callee must match, or the behavior of the program is undefined. The
				588	following calling conventions are supported by LLVM, and more may be added in
				589	the future:</p>
				590
				591	<dl>
				592	<dt><b>"<tt>ccc</tt>" - The C calling convention</b>:</dt>
				593
				594	<dd>This calling convention (the default if no other calling convention is
				595	specified) matches the target C calling conventions. This calling convention
John Criswell	02fdc6f	2005-05-12 16:52:32 +0000	[diff] [blame]	596	supports varargs function calls and tolerates some mismatch in the declared
Reid Spencer	72ba499	2006-12-31 21:30:18 +0000	[diff] [blame]	597	prototype and implemented declaration of the function (as does normal C).
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	598	</dd>
				599
				600	<dt><b>"<tt>fastcc</tt>" - The fast calling convention</b>:</dt>
				601
				602	<dd>This calling convention attempts to make calls as fast as possible
				603	(e.g. by passing things in registers). This calling convention allows the
				604	target to use whatever tricks it wants to produce fast code for the target,
Chris Lattner	67c37d1	2008-08-05 18:29:16 +0000	[diff] [blame]	605	without having to conform to an externally specified ABI (Application Binary
				606	Interface). Implementations of this convention should allow arbitrary
Arnold Schwaighofer	2c6b888	2008-05-14 09:17:12 +0000	[diff] [blame]	607	<a href="CodeGenerator.html#tailcallopt">tail call optimization</a> to be
				608	supported. This calling convention does not support varargs and requires the
				609	prototype of all callees to exactly match the prototype of the function
				610	definition.
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	611	</dd>
				612
				613	<dt><b>"<tt>coldcc</tt>" - The cold calling convention</b>:</dt>
				614
				615	<dd>This calling convention attempts to make code in the caller as efficient
				616	as possible under the assumption that the call is not commonly executed. As
				617	such, these calls often preserve all registers so that the call does not break
				618	any live ranges in the caller side. This calling convention does not support
				619	varargs and requires the prototype of all callees to exactly match the
				620	prototype of the function definition.
				621	</dd>
				622
Chris Lattner	573f64e	2005-05-07 01:46:40 +0000	[diff] [blame]	623	<dt><b>"<tt>cc <<em>n</em>></tt>" - Numbered convention</b>:</dt>
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	624
				625	<dd>Any calling convention may be specified by number, allowing
				626	target-specific calling conventions to be used. Target specific calling
				627	conventions start at 64.
				628	</dd>
Chris Lattner	573f64e	2005-05-07 01:46:40 +0000	[diff] [blame]	629	</dl>
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	630
				631	<p>More calling conventions can be added/defined on an as-needed basis, to
				632	support pascal conventions or any other well-known target-independent
				633	convention.</p>
				634
				635	</div>
				636
				637	<!-- ======================================================================= -->
				638	<div class="doc_subsection">
Anton Korobeynikov	c7f9f3d	2007-01-23 12:35:46 +0000	[diff] [blame]	639	<a name="visibility">Visibility Styles</a>
				640	</div>
				641
				642	<div class="doc_text">
				643
				644	<p>
				645	All Global Variables and Functions have one of the following visibility styles:
				646	</p>
				647
				648	<dl>
				649	<dt><b>"<tt>default</tt>" - Default style</b>:</dt>
				650
Chris Lattner	67c37d1	2008-08-05 18:29:16 +0000	[diff] [blame]	651	<dd>On targets that use the ELF object file format, default visibility means
				652	that the declaration is visible to other
Anton Korobeynikov	c7f9f3d	2007-01-23 12:35:46 +0000	[diff] [blame]	653	modules and, in shared libraries, means that the declared entity may be
				654	overridden. On Darwin, default visibility means that the declaration is
				655	visible to other modules. Default visibility corresponds to "external
				656	linkage" in the language.
				657	</dd>
				658
				659	<dt><b>"<tt>hidden</tt>" - Hidden style</b>:</dt>
				660
				661	<dd>Two declarations of an object with hidden visibility refer to the same
				662	object if they are in the same shared object. Usually, hidden visibility
				663	indicates that the symbol will not be placed into the dynamic symbol table,
				664	so no other module (executable or shared library) can reference it
				665	directly.
				666	</dd>
				667
Anton Korobeynikov	39f3cff	2007-04-29 18:35:00 +0000	[diff] [blame]	668	<dt><b>"<tt>protected</tt>" - Protected style</b>:</dt>
				669
				670	<dd>On ELF, protected visibility indicates that the symbol will be placed in
				671	the dynamic symbol table, but that references within the defining module will
				672	bind to the local symbol. That is, the symbol cannot be overridden by another
				673	module.
				674	</dd>
Anton Korobeynikov	c7f9f3d	2007-01-23 12:35:46 +0000	[diff] [blame]	675	</dl>
				676
				677	</div>
				678
				679	<!-- ======================================================================= -->
				680	<div class="doc_subsection">
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	681	<a name="globalvars">Global Variables</a>
				682	</div>
				683
				684	<div class="doc_text">
				685
Chris Lattner	5d5aede	2005-02-12 19:30:21 +0000	[diff] [blame]	686	<p>Global variables define regions of memory allocated at compilation time
Chris Lattner	662c872	2005-11-12 00:45:07 +0000	[diff] [blame]	687	instead of run-time. Global variables may optionally be initialized, may have
Anton Korobeynikov	a97b694	2007-04-25 14:27:10 +0000	[diff] [blame]	688	an explicit section to be placed in, and may have an optional explicit alignment
				689	specified. A variable may be defined as "thread_local", which means that it
				690	will not be shared by threads (each thread will have a separated copy of the
				691	variable). A variable may be defined as a global "constant," which indicates
				692	that the contents of the variable will <b>never</b> be modified (enabling better
Chris Lattner	5d5aede	2005-02-12 19:30:21 +0000	[diff] [blame]	693	optimization, allowing the global data to be placed in the read-only section of
				694	an executable, etc). Note that variables that need runtime initialization
John Criswell	4c0cf7f	2005-10-24 16:17:18 +0000	[diff] [blame]	695	cannot be marked "constant" as there is a store to the variable.</p>
Chris Lattner	5d5aede	2005-02-12 19:30:21 +0000	[diff] [blame]	696
				697	<p>
				698	LLVM explicitly allows <em>declarations</em> of global variables to be marked
				699	constant, even if the final definition of the global is not. This capability
				700	can be used to enable slightly better optimization of the program, but requires
				701	the language definition to guarantee that optimizations based on the
				702	'constantness' are valid for the translation units that do not include the
				703	definition.
				704	</p>
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	705
				706	<p>As SSA values, global variables define pointer values that are in
				707	scope (i.e. they dominate) all basic blocks in the program. Global
				708	variables always define a pointer to their "content" type because they
				709	describe a region of memory, and all memory objects in LLVM are
				710	accessed through pointers.</p>
				711
Christopher Lamb	308121c	2007-12-11 09:31:00 +0000	[diff] [blame]	712	<p>A global variable may be declared to reside in a target-specifc numbered
				713	address space. For targets that support them, address spaces may affect how
				714	optimizations are performed and/or what target instructions are used to access
Christopher Lamb	25f5076	2007-12-12 08:44:39 +0000	[diff] [blame]	715	the variable. The default address space is zero. The address space qualifier
				716	must precede any other attributes.</p>
Christopher Lamb	308121c	2007-12-11 09:31:00 +0000	[diff] [blame]	717
Chris Lattner	662c872	2005-11-12 00:45:07 +0000	[diff] [blame]	718	<p>LLVM allows an explicit section to be specified for globals. If the target
				719	supports it, it will emit globals to the section specified.</p>
				720
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	721	<p>An explicit alignment may be specified for a global. If not present, or if
				722	the alignment is set to zero, the alignment of the global is set by the target
				723	to whatever it feels convenient. If an explicit alignment is specified, the
				724	global is forced to have at least that much alignment. All alignments must be
				725	a power of 2.</p>
				726
Christopher Lamb	308121c	2007-12-11 09:31:00 +0000	[diff] [blame]	727	<p>For example, the following defines a global in a numbered address space with
				728	an initializer, section, and alignment:</p>
Chris Lattner	5760c50	2007-01-14 00:27:09 +0000	[diff] [blame]	729
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	730	<div class="doc_code">
Chris Lattner	5760c50	2007-01-14 00:27:09 +0000	[diff] [blame]	731	<pre>
Christopher Lamb	308121c	2007-12-11 09:31:00 +0000	[diff] [blame]	732	@G = constant float 1.0 addrspace(5), section "foo", align 4
Chris Lattner	5760c50	2007-01-14 00:27:09 +0000	[diff] [blame]	733	</pre>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	734	</div>
Chris Lattner	5760c50	2007-01-14 00:27:09 +0000	[diff] [blame]	735
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	736	</div>
				737
				738
				739	<!-- ======================================================================= -->
				740	<div class="doc_subsection">
				741	<a name="functionstructure">Functions</a>
				742	</div>
				743
				744	<div class="doc_text">
				745
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	746	<p>LLVM function definitions consist of the "<tt>define</tt>" keyord,
				747	an optional <a href="#linkage">linkage type</a>, an optional
Anton Korobeynikov	c7f9f3d	2007-01-23 12:35:46 +0000	[diff] [blame]	748	<a href="#visibility">visibility style</a>, an optional
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	749	<a href="#callingconv">calling convention</a>, a return type, an optional
				750	<a href="#paramattrs">parameter attribute</a> for the return type, a function
				751	name, a (possibly empty) argument list (each with optional
Devang Patel	7e9b05e	2008-10-06 18:50:38 +0000	[diff] [blame]	752	<a href="#paramattrs">parameter attributes</a>), optional
				753	<a href="#fnattrs">function attributes</a>, an optional section,
				754	an optional alignment, an optional <a href="#gc">garbage collector name</a>,
Chris Lattner	cbc4d2a	2008-10-04 18:10:21 +0000	[diff] [blame]	755	an opening curly brace, a list of basic blocks, and a closing curly brace.
Anton Korobeynikov	c7f9f3d	2007-01-23 12:35:46 +0000	[diff] [blame]	756
				757	LLVM function declarations consist of the "<tt>declare</tt>" keyword, an
				758	optional <a href="#linkage">linkage type</a>, an optional
				759	<a href="#visibility">visibility style</a>, an optional
				760	<a href="#callingconv">calling convention</a>, a return type, an optional
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	761	<a href="#paramattrs">parameter attribute</a> for the return type, a function
Gordon Henriksen	71183b6	2007-12-10 03:18:06 +0000	[diff] [blame]	762	name, a possibly empty list of arguments, an optional alignment, and an optional
Gordon Henriksen	dc5cafb	2007-12-10 03:30:21 +0000	[diff] [blame]	763	<a href="#gc">garbage collector name</a>.</p>
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	764
Chris Lattner	67c37d1	2008-08-05 18:29:16 +0000	[diff] [blame]	765	<p>A function definition contains a list of basic blocks, forming the CFG
				766	(Control Flow Graph) for
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	767	the function. Each basic block may optionally start with a label (giving the
				768	basic block a symbol table entry), contains a list of instructions, and ends
				769	with a <a href="#terminators">terminator</a> instruction (such as a branch or
				770	function return).</p>
				771
Chris Lattner	a59fb10	2007-06-08 16:52:14 +0000	[diff] [blame]	772	<p>The first basic block in a function is special in two ways: it is immediately
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	773	executed on entrance to the function, and it is not allowed to have predecessor
				774	basic blocks (i.e. there can not be any branches to the entry block of a
				775	function). Because the block can have no predecessors, it also cannot have any
				776	<a href="#i_phi">PHI nodes</a>.</p>
				777
Chris Lattner	662c872	2005-11-12 00:45:07 +0000	[diff] [blame]	778	<p>LLVM allows an explicit section to be specified for functions. If the target
				779	supports it, it will emit functions to the section specified.</p>
				780
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	781	<p>An explicit alignment may be specified for a function. If not present, or if
				782	the alignment is set to zero, the alignment of the function is set by the target
				783	to whatever it feels convenient. If an explicit alignment is specified, the
				784	function is forced to have at least that much alignment. All alignments must be
				785	a power of 2.</p>
				786
Devang Patel	0225623	2008-10-07 17:48:33 +0000	[diff] [blame]	787	<h5>Syntax:</h5>
				788
				789	<div class="doc_code">
				790	<pre>
				791	define [<a href="#linkage">linkage</a>] [<a href="#visibility">visibility</a>] [<a href="#callingconv">cconv</a>] [<a href="#paramattrs">ret attrs</a>] <ResultType> @<FunctionName> ([argument list]) [<a href="#fnattrs">fn Attrs</a>] [section "name"] [align N] [<a href="#gc">gc</a>] { ... }
				792	</pre>
				793	</div>
				794
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	795	</div>
				796
Anton Korobeynikov	a97b694	2007-04-25 14:27:10 +0000	[diff] [blame]	797
				798	<!-- ======================================================================= -->
				799	<div class="doc_subsection">
				800	<a name="aliasstructure">Aliases</a>
				801	</div>
				802	<div class="doc_text">
				803	<p>Aliases act as "second name" for the aliasee value (which can be either
Anton Korobeynikov	25b2e82	2008-03-22 08:36:14 +0000	[diff] [blame]	804	function, global variable, another alias or bitcast of global value). Aliases
				805	may have an optional <a href="#linkage">linkage type</a>, and an
Anton Korobeynikov	a97b694	2007-04-25 14:27:10 +0000	[diff] [blame]	806	optional <a href="#visibility">visibility style</a>.</p>
				807
				808	<h5>Syntax:</h5>
				809
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	810	<div class="doc_code">
Bill Wendling	2d8b9a8	2007-05-29 09:42:13 +0000	[diff] [blame]	811	<pre>
Duncan Sands	7e99a94	2008-09-12 20:48:21 +0000	[diff] [blame]	812	@<Name> = alias [Linkage] [Visibility] <AliaseeTy> @<Aliasee>
Bill Wendling	2d8b9a8	2007-05-29 09:42:13 +0000	[diff] [blame]	813	</pre>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	814	</div>
Anton Korobeynikov	a97b694	2007-04-25 14:27:10 +0000	[diff] [blame]	815
				816	</div>
				817
				818
				819
Chris Lattner	91c15c4	2006-01-23 23:23:47 +0000	[diff] [blame]	820	<!-- ======================================================================= -->
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	821	<div class="doc_subsection"><a name="paramattrs">Parameter Attributes</a></div>
				822	<div class="doc_text">
				823	<p>The return type and each parameter of a function type may have a set of
				824	<i>parameter attributes</i> associated with them. Parameter attributes are
				825	used to communicate additional information about the result or parameters of
Duncan Sands	ad0ea2d	2007-11-27 13:23:08 +0000	[diff] [blame]	826	a function. Parameter attributes are considered to be part of the function,
				827	not of the function type, so functions with different parameter attributes
				828	can have the same function type.</p>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	829
Reid Spencer	cf7ebf5	2007-01-15 18:27:39 +0000	[diff] [blame]	830	<p>Parameter attributes are simple keywords that follow the type specified. If
				831	multiple parameter attributes are needed, they are space separated. For
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	832	example:</p>
				833
				834	<div class="doc_code">
				835	<pre>
Devang Patel	9eb525d	2008-09-26 23:51:19 +0000	[diff] [blame]	836	declare i32 @printf(i8* noalias , ...)
Chris Lattner	d2597d7	2008-10-04 18:33:34 +0000	[diff] [blame]	837	declare i32 @atoi(i8 zeroext)
				838	declare signext i8 @returns_signed_char()
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	839	</pre>
				840	</div>
				841
Duncan Sands	ad0ea2d	2007-11-27 13:23:08 +0000	[diff] [blame]	842	<p>Note that any attributes for the function result (<tt>nounwind</tt>,
				843	<tt>readonly</tt>) come immediately after the argument list.</p>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	844
Anton Korobeynikov	a0554d9	2007-01-12 19:20:47 +0000	[diff] [blame]	845	<p>Currently, only the following parameter attributes are defined:</p>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	846	<dl>
Reid Spencer	314e1cb	2007-07-19 23:13:04 +0000	[diff] [blame]	847	<dt><tt>zeroext</tt></dt>
Chris Lattner	d2597d7	2008-10-04 18:33:34 +0000	[diff] [blame]	848	<dd>This indicates to the code generator that the parameter or return value
				849	should be zero-extended to a 32-bit value by the caller (for a parameter)
				850	or the callee (for a return value).</dd>
Chris Lattner	5cee13f	2008-01-11 06:20:47 +0000	[diff] [blame]	851
Reid Spencer	314e1cb	2007-07-19 23:13:04 +0000	[diff] [blame]	852	<dt><tt>signext</tt></dt>
Chris Lattner	d2597d7	2008-10-04 18:33:34 +0000	[diff] [blame]	853	<dd>This indicates to the code generator that the parameter or return value
				854	should be sign-extended to a 32-bit value by the caller (for a parameter)
				855	or the callee (for a return value).</dd>
Chris Lattner	5cee13f	2008-01-11 06:20:47 +0000	[diff] [blame]	856
Anton Korobeynikov	e816685	2007-01-28 14:30:45 +0000	[diff] [blame]	857	<dt><tt>inreg</tt></dt>
Dale Johannesen	c50ada2	2008-09-25 20:47:45 +0000	[diff] [blame]	858	<dd>This indicates that this parameter or return value should be treated
				859	in a special target-dependent fashion during while emitting code for a
				860	function call or return (usually, by putting it in a register as opposed
Chris Lattner	d2597d7	2008-10-04 18:33:34 +0000	[diff] [blame]	861	to memory, though some targets use it to distinguish between two different
				862	kinds of registers). Use of this attribute is target-specific.</dd>
Chris Lattner	5cee13f	2008-01-11 06:20:47 +0000	[diff] [blame]	863
Duncan Sands	2a1d8ba	2008-10-06 08:14:18 +0000	[diff] [blame]	864	<dt><tt><a name="byval">byval</a></tt></dt>
Chris Lattner	352ab9b	2008-01-15 04:34:22 +0000	[diff] [blame]	865	<dd>This indicates that the pointer parameter should really be passed by
				866	value to the function. The attribute implies that a hidden copy of the
				867	pointee is made between the caller and the callee, so the callee is unable
Chris Lattner	1ca5c64	2008-08-05 18:21:08 +0000	[diff] [blame]	868	to modify the value in the callee. This attribute is only valid on LLVM
Chris Lattner	352ab9b	2008-01-15 04:34:22 +0000	[diff] [blame]	869	pointer arguments. It is generally used to pass structs and arrays by
Duncan Sands	2a1d8ba	2008-10-06 08:14:18 +0000	[diff] [blame]	870	value, but is also valid on pointers to scalars. The copy is considered to
				871	belong to the caller not the callee (for example,
				872	<tt><a href="#readonly">readonly</a></tt> functions should not write to
Devang Patel	7e9b05e	2008-10-06 18:50:38 +0000	[diff] [blame]	873	<tt>byval</tt> parameters). This is not a valid attribute for return
				874	values. </dd>
Chris Lattner	5cee13f	2008-01-11 06:20:47 +0000	[diff] [blame]	875
Anton Korobeynikov	e816685	2007-01-28 14:30:45 +0000	[diff] [blame]	876	<dt><tt>sret</tt></dt>
Duncan Sands	fa4b673	2008-02-18 04:19:38 +0000	[diff] [blame]	877	<dd>This indicates that the pointer parameter specifies the address of a
				878	structure that is the return value of the function in the source program.
Chris Lattner	d2597d7	2008-10-04 18:33:34 +0000	[diff] [blame]	879	This pointer must be guaranteed by the caller to be valid: loads and stores
				880	to the structure may be assumed by the callee to not to trap. This may only
Devang Patel	7e9b05e	2008-10-06 18:50:38 +0000	[diff] [blame]	881	be applied to the first parameter. This is not a valid attribute for
				882	return values. </dd>
Chris Lattner	5cee13f	2008-01-11 06:20:47 +0000	[diff] [blame]	883
Zhou Sheng	2444a9a	2007-06-05 05:28:26 +0000	[diff] [blame]	884	<dt><tt>noalias</tt></dt>
Owen Anderson	6110128	2008-02-18 04:09:01 +0000	[diff] [blame]	885	<dd>This indicates that the parameter does not alias any global or any other
				886	parameter. The caller is responsible for ensuring that this is the case,
Devang Patel	7e9b05e	2008-10-06 18:50:38 +0000	[diff] [blame]	887	usually by placing the value in a stack allocation. This is not a valid
				888	attribute for return values.</dd>
Chris Lattner	5cee13f	2008-01-11 06:20:47 +0000	[diff] [blame]	889
Duncan Sands	27e9159	2007-07-27 19:57:41 +0000	[diff] [blame]	890	<dt><tt>nest</tt></dt>
Duncan Sands	825bde4	2008-07-08 09:27:25 +0000	[diff] [blame]	891	<dd>This indicates that the pointer parameter can be excised using the
Devang Patel	7e9b05e	2008-10-06 18:50:38 +0000	[diff] [blame]	892	<a href="#int_trampoline">trampoline intrinsics</a>. This is not a valid
				893	attribute for return values.</dd>
Anton Korobeynikov	a0554d9	2007-01-12 19:20:47 +0000	[diff] [blame]	894	</dl>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	895
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	896	</div>
				897
				898	<!-- ======================================================================= -->
Chris Lattner	91c15c4	2006-01-23 23:23:47 +0000	[diff] [blame]	899	<div class="doc_subsection">
Gordon Henriksen	71183b6	2007-12-10 03:18:06 +0000	[diff] [blame]	900	<a name="gc">Garbage Collector Names</a>
				901	</div>
				902
				903	<div class="doc_text">
				904	<p>Each function may specify a garbage collector name, which is simply a
				905	string.</p>
				906
				907	<div class="doc_code"><pre
				908	>define void @f() gc "name" { ...</pre></div>
				909
				910	<p>The compiler declares the supported values of <i>name</i>. Specifying a
				911	collector which will cause the compiler to alter its output in order to support
				912	the named garbage collection algorithm.</p>
				913	</div>
				914
				915	<!-- ======================================================================= -->
				916	<div class="doc_subsection">
Devang Patel	9eb525d	2008-09-26 23:51:19 +0000	[diff] [blame]	917	<a name="fnattrs">Function Attributes</a>
Devang Patel	caacdba	2008-09-04 23:05:13 +0000	[diff] [blame]	918	</div>
				919
				920	<div class="doc_text">
Devang Patel	9eb525d	2008-09-26 23:51:19 +0000	[diff] [blame]	921
				922	<p>Function attributes are set to communicate additional information about
				923	a function. Function attributes are considered to be part of the function,
				924	not of the function type, so functions with different parameter attributes
				925	can have the same function type.</p>
				926
				927	<p>Function attributes are simple keywords that follow the type specified. If
				928	multiple attributes are needed, they are space separated. For
				929	example:</p>
Devang Patel	caacdba	2008-09-04 23:05:13 +0000	[diff] [blame]	930
				931	<div class="doc_code">
Bill Wendling	b175fa4	2008-09-07 10:26:33 +0000	[diff] [blame]	932	<pre>
Devang Patel	9eb525d	2008-09-26 23:51:19 +0000	[diff] [blame]	933	define void @f() noinline { ... }
				934	define void @f() alwaysinline { ... }
				935	define void @f() alwaysinline optsize { ... }
				936	define void @f() optsize
Bill Wendling	b175fa4	2008-09-07 10:26:33 +0000	[diff] [blame]	937	</pre>
Devang Patel	caacdba	2008-09-04 23:05:13 +0000	[diff] [blame]	938	</div>
				939
Bill Wendling	b175fa4	2008-09-07 10:26:33 +0000	[diff] [blame]	940	<dl>
Devang Patel	9eb525d	2008-09-26 23:51:19 +0000	[diff] [blame]	941	<dt><tt>alwaysinline</tt></dt>
Chris Lattner	fbf60a4	2008-10-04 18:23:17 +0000	[diff] [blame]	942	<dd>This attribute indicates that the inliner should attempt to inline this
				943	function into callers whenever possible, ignoring any active inlining size
				944	threshold for this caller.</dd>
Bill Wendling	b175fa4	2008-09-07 10:26:33 +0000	[diff] [blame]	945
Devang Patel	9eb525d	2008-09-26 23:51:19 +0000	[diff] [blame]	946	<dt><tt>noinline</tt></dt>
Chris Lattner	fbf60a4	2008-10-04 18:23:17 +0000	[diff] [blame]	947	<dd>This attribute indicates that the inliner should never inline this function
Chris Lattner	0625c28	2008-10-05 17:14:59 +0000	[diff] [blame]	948	in any situation. This attribute may not be used together with the
Chris Lattner	fbf60a4	2008-10-04 18:23:17 +0000	[diff] [blame]	949	<tt>alwaysinline</tt> attribute.</dd>
Bill Wendling	b175fa4	2008-09-07 10:26:33 +0000	[diff] [blame]	950
Devang Patel	9eb525d	2008-09-26 23:51:19 +0000	[diff] [blame]	951	<dt><tt>optsize</tt></dt>
Devang Patel	e974390	2008-09-29 18:34:44 +0000	[diff] [blame]	952	<dd>This attribute suggests that optimization passes and code generator passes
Chris Lattner	fbf60a4	2008-10-04 18:23:17 +0000	[diff] [blame]	953	make choices that keep the code size of this function low, and otherwise do
				954	optimizations specifically to reduce code size.</dd>
Bill Wendling	b175fa4	2008-09-07 10:26:33 +0000	[diff] [blame]	955
Devang Patel	9eb525d	2008-09-26 23:51:19 +0000	[diff] [blame]	956	<dt><tt>noreturn</tt></dt>
Chris Lattner	fbf60a4	2008-10-04 18:23:17 +0000	[diff] [blame]	957	<dd>This function attribute indicates that the function never returns normally.
				958	This produces undefined behavior at runtime if the function ever does
				959	dynamically return.</dd>
Devang Patel	9eb525d	2008-09-26 23:51:19 +0000	[diff] [blame]	960
				961	<dt><tt>nounwind</tt></dt>
Chris Lattner	fbf60a4	2008-10-04 18:23:17 +0000	[diff] [blame]	962	<dd>This function attribute indicates that the function never returns with an
				963	unwind or exceptional control flow. If the function does unwind, its runtime
				964	behavior is undefined.</dd>
				965
				966	<dt><tt>readnone</tt></dt>
Duncan Sands	2a1d8ba	2008-10-06 08:14:18 +0000	[diff] [blame]	967	<dd>This attribute indicates that the function computes its result (or the
				968	exception it throws) based strictly on its arguments, without dereferencing any
				969	pointer arguments or otherwise accessing any mutable state (e.g. memory, control
				970	registers, etc) visible to caller functions. It does not write through any
				971	pointer arguments (including <tt><a href="#byval">byval</a></tt> arguments) and
				972	never changes any state visible to callers.</dd>
Devang Patel	9eb525d	2008-09-26 23:51:19 +0000	[diff] [blame]	973
Duncan Sands	2a1d8ba	2008-10-06 08:14:18 +0000	[diff] [blame]	974	<dt><tt><a name="readonly">readonly</a></tt></dt>
				975	<dd>This attribute indicates that the function does not write through any
				976	pointer arguments (including <tt><a href="#byval">byval</a></tt> arguments)
				977	or otherwise modify any state (e.g. memory, control registers, etc) visible to
				978	caller functions. It may dereference pointer arguments and read state that may
				979	be set in the caller. A readonly function always returns the same value (or
				980	throws the same exception) when called with the same set of arguments and global
				981	state.</dd>
Bill Wendling	b175fa4	2008-09-07 10:26:33 +0000	[diff] [blame]	982	</dl>
				983
Devang Patel	caacdba	2008-09-04 23:05:13 +0000	[diff] [blame]	984	</div>
				985
				986	<!-- ======================================================================= -->
				987	<div class="doc_subsection">
Chris Lattner	9356489	2006-04-08 04:40:53 +0000	[diff] [blame]	988	<a name="moduleasm">Module-Level Inline Assembly</a>
Chris Lattner	91c15c4	2006-01-23 23:23:47 +0000	[diff] [blame]	989	</div>
				990
				991	<div class="doc_text">
				992	<p>
				993	Modules may contain "module-level inline asm" blocks, which corresponds to the
				994	GCC "file scope inline asm" blocks. These blocks are internally concatenated by
				995	LLVM and treated as a single unit, but may be separated in the .ll file if
				996	desired. The syntax is very simple:
				997	</p>
				998
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	999	<div class="doc_code">
				1000	<pre>
				1001	module asm "inline asm code goes here"
				1002	module asm "more can go here"
				1003	</pre>
				1004	</div>
Chris Lattner	91c15c4	2006-01-23 23:23:47 +0000	[diff] [blame]	1005
				1006	<p>The strings can contain any character by escaping non-printable characters.
				1007	The escape sequence used is simply "\xx" where "xx" is the two digit hex code
				1008	for the number.
				1009	</p>
				1010
				1011	<p>
				1012	The inline asm code is simply printed to the machine code .s file when
				1013	assembly code is generated.
				1014	</p>
				1015	</div>
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	1016
Reid Spencer	50c723a	2007-02-19 23:54:10 +0000	[diff] [blame]	1017	<!-- ======================================================================= -->
				1018	<div class="doc_subsection">
				1019	<a name="datalayout">Data Layout</a>
				1020	</div>
				1021
				1022	<div class="doc_text">
				1023	<p>A module may specify a target specific data layout string that specifies how
Reid Spencer	7972c47	2007-04-11 23:49:50 +0000	[diff] [blame]	1024	data is to be laid out in memory. The syntax for the data layout is simply:</p>
				1025	<pre> target datalayout = "<i>layout specification</i>"</pre>
				1026	<p>The <i>layout specification</i> consists of a list of specifications
				1027	separated by the minus sign character ('-'). Each specification starts with a
				1028	letter and may include other information after the letter to define some
				1029	aspect of the data layout. The specifications accepted are as follows: </p>
Reid Spencer	50c723a	2007-02-19 23:54:10 +0000	[diff] [blame]	1030	<dl>
				1031	<dt><tt>E</tt></dt>
				1032	<dd>Specifies that the target lays out data in big-endian form. That is, the
				1033	bits with the most significance have the lowest address location.</dd>
				1034	<dt><tt>e</tt></dt>
Chris Lattner	67c37d1	2008-08-05 18:29:16 +0000	[diff] [blame]	1035	<dd>Specifies that the target lays out data in little-endian form. That is,
Reid Spencer	50c723a	2007-02-19 23:54:10 +0000	[diff] [blame]	1036	the bits with the least significance have the lowest address location.</dd>
				1037	<dt><tt>p:<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
				1038	<dd>This specifies the <i>size</i> of a pointer and its <i>abi</i> and
				1039	<i>preferred</i> alignments. All sizes are in bits. Specifying the <i>pref</i>
				1040	alignment is optional. If omitted, the preceding <tt>:</tt> should be omitted
				1041	too.</dd>
				1042	<dt><tt>i<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
				1043	<dd>This specifies the alignment for an integer type of a given bit
				1044	<i>size</i>. The value of <i>size</i> must be in the range [1,2^23).</dd>
				1045	<dt><tt>v<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
				1046	<dd>This specifies the alignment for a vector type of a given bit
				1047	<i>size</i>.</dd>
				1048	<dt><tt>f<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
				1049	<dd>This specifies the alignment for a floating point type of a given bit
				1050	<i>size</i>. The value of <i>size</i> must be either 32 (float) or 64
				1051	(double).</dd>
				1052	<dt><tt>a<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
				1053	<dd>This specifies the alignment for an aggregate type of a given bit
				1054	<i>size</i>.</dd>
				1055	</dl>
				1056	<p>When constructing the data layout for a given target, LLVM starts with a
				1057	default set of specifications which are then (possibly) overriden by the
				1058	specifications in the <tt>datalayout</tt> keyword. The default specifications
				1059	are given in this list:</p>
				1060	<ul>
				1061	<li><tt>E</tt> - big endian</li>
				1062	<li><tt>p:32:64:64</tt> - 32-bit pointers with 64-bit alignment</li>
				1063	<li><tt>i1:8:8</tt> - i1 is 8-bit (byte) aligned</li>
				1064	<li><tt>i8:8:8</tt> - i8 is 8-bit (byte) aligned</li>
				1065	<li><tt>i16:16:16</tt> - i16 is 16-bit aligned</li>
				1066	<li><tt>i32:32:32</tt> - i32 is 32-bit aligned</li>
Chris Lattner	67c37d1	2008-08-05 18:29:16 +0000	[diff] [blame]	1067	<li><tt>i64:32:64</tt> - i64 has ABI alignment of 32-bits but preferred
Reid Spencer	50c723a	2007-02-19 23:54:10 +0000	[diff] [blame]	1068	alignment of 64-bits</li>
				1069	<li><tt>f32:32:32</tt> - float is 32-bit aligned</li>
				1070	<li><tt>f64:64:64</tt> - double is 64-bit aligned</li>
				1071	<li><tt>v64:64:64</tt> - 64-bit vector is 64-bit aligned</li>
				1072	<li><tt>v128:128:128</tt> - 128-bit vector is 128-bit aligned</li>
				1073	<li><tt>a0:0:1</tt> - aggregates are 8-bit aligned</li>
				1074	</ul>
Chris Lattner	1ca5c64	2008-08-05 18:21:08 +0000	[diff] [blame]	1075	<p>When LLVM is determining the alignment for a given type, it uses the
Reid Spencer	50c723a	2007-02-19 23:54:10 +0000	[diff] [blame]	1076	following rules:
				1077	<ol>
				1078	<li>If the type sought is an exact match for one of the specifications, that
				1079	specification is used.</li>
				1080	<li>If no match is found, and the type sought is an integer type, then the
				1081	smallest integer type that is larger than the bitwidth of the sought type is
				1082	used. If none of the specifications are larger than the bitwidth then the the
				1083	largest integer type is used. For example, given the default specifications
				1084	above, the i7 type will use the alignment of i8 (next largest) while both
				1085	i65 and i256 will use the alignment of i64 (largest specified).</li>
				1086	<li>If no match is found, and the type sought is a vector type, then the
				1087	largest vector type that is smaller than the sought vector type will be used
				1088	as a fall back. This happens because <128 x double> can be implemented in
				1089	terms of 64 <2 x double>, for example.</li>
				1090	</ol>
				1091	</div>
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	1092
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1093	<!-- *********************************************************************** -->
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1094	<div class="doc_section"> <a name="typesystem">Type System</a> </div>
				1095	<!-- *********************************************************************** -->
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	1096
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1097	<div class="doc_text">
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	1098
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1099	<p>The LLVM type system is one of the most important features of the
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1100	intermediate representation. Being typed enables a number of
Chris Lattner	67c37d1	2008-08-05 18:29:16 +0000	[diff] [blame]	1101	optimizations to be performed on the intermediate representation directly,
				1102	without having to do
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1103	extra analyses on the side before the transformation. A strong type
				1104	system makes it easier to read the generated code and enables novel
				1105	analyses and transformations that are not feasible to perform on normal
				1106	three address code representations.</p>
Chris Lattner	6af02f3	2004-12-09 16:11:40 +0000	[diff] [blame]	1107
				1108	</div>
				1109
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1110	<!-- ======================================================================= -->
Chris Lattner	7824d18	2008-01-04 04:32:38 +0000	[diff] [blame]	1111	<div class="doc_subsection"> <a name="t_classifications">Type
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1112	Classifications</a> </div>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1113	<div class="doc_text">
Chris Lattner	7824d18	2008-01-04 04:32:38 +0000	[diff] [blame]	1114	<p>The types fall into a few useful
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1115	classifications:</p>
Misha Brukman	c501f55	2004-03-01 17:47:27 +0000	[diff] [blame]	1116
				1117	<table border="1" cellspacing="0" cellpadding="4">
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1118	<tbody>
Reid Spencer	c3c4c4f	2004-11-01 08:19:36 +0000	[diff] [blame]	1119	<tr><th>Classification</th><th>Types</th></tr>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1120	<tr>
Chris Lattner	7824d18	2008-01-04 04:32:38 +0000	[diff] [blame]	1121	<td><a href="#t_integer">integer</a></td>
Reid Spencer	138249b	2007-05-16 18:44:01 +0000	[diff] [blame]	1122	<td><tt>i1, i2, i3, ... i8, ... i16, ... i32, ... i64, ... </tt></td>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1123	</tr>
				1124	<tr>
Chris Lattner	7824d18	2008-01-04 04:32:38 +0000	[diff] [blame]	1125	<td><a href="#t_floating">floating point</a></td>
				1126	<td><tt>float, double, x86_fp80, fp128, ppc_fp128</tt></td>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1127	</tr>
				1128	<tr>
				1129	<td><a name="t_firstclass">first class</a></td>
Chris Lattner	7824d18	2008-01-04 04:32:38 +0000	[diff] [blame]	1130	<td><a href="#t_integer">integer</a>,
				1131	<a href="#t_floating">floating point</a>,
				1132	<a href="#t_pointer">pointer</a>,
Dan Gohman	08783a88	2008-06-18 18:42:13 +0000	[diff] [blame]	1133	<a href="#t_vector">vector</a>,
Dan Gohman	b9d6660	2008-05-12 23:51:09 +0000	[diff] [blame]	1134	<a href="#t_struct">structure</a>,
				1135	<a href="#t_array">array</a>,
Dan Gohman	da52d21	2008-05-23 22:50:26 +0000	[diff] [blame]	1136	<a href="#t_label">label</a>.
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	1137	</td>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1138	</tr>
Chris Lattner	7824d18	2008-01-04 04:32:38 +0000	[diff] [blame]	1139	<tr>
				1140	<td><a href="#t_primitive">primitive</a></td>
				1141	<td><a href="#t_label">label</a>,
				1142	<a href="#t_void">void</a>,
Chris Lattner	7824d18	2008-01-04 04:32:38 +0000	[diff] [blame]	1143	<a href="#t_floating">floating point</a>.</td>
				1144	</tr>
				1145	<tr>
				1146	<td><a href="#t_derived">derived</a></td>
				1147	<td><a href="#t_integer">integer</a>,
				1148	<a href="#t_array">array</a>,
				1149	<a href="#t_function">function</a>,
				1150	<a href="#t_pointer">pointer</a>,
				1151	<a href="#t_struct">structure</a>,
				1152	<a href="#t_pstruct">packed structure</a>,
				1153	<a href="#t_vector">vector</a>,
				1154	<a href="#t_opaque">opaque</a>.
				1155	</tr>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1156	</tbody>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1157	</table>
Misha Brukman	c501f55	2004-03-01 17:47:27 +0000	[diff] [blame]	1158
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1159	<p>The <a href="#t_firstclass">first class</a> types are perhaps the
				1160	most important. Values of these types are the only ones which can be
				1161	produced by instructions, passed as arguments, or used as operands to
Dan Gohman	34d1c0d	2008-05-23 21:53:15 +0000	[diff] [blame]	1162	instructions.</p>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1163	</div>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1164
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1165	<!-- ======================================================================= -->
Chris Lattner	7824d18	2008-01-04 04:32:38 +0000	[diff] [blame]	1166	<div class="doc_subsection"> <a name="t_primitive">Primitive Types</a> </div>
Chris Lattner	43542b3	2008-01-04 04:34:14 +0000	[diff] [blame]	1167
Chris Lattner	7824d18	2008-01-04 04:32:38 +0000	[diff] [blame]	1168	<div class="doc_text">
				1169	<p>The primitive types are the fundamental building blocks of the LLVM
				1170	system.</p>
				1171
Chris Lattner	43542b3	2008-01-04 04:34:14 +0000	[diff] [blame]	1172	</div>
				1173
Chris Lattner	7824d18	2008-01-04 04:32:38 +0000	[diff] [blame]	1174	<!-- _______________________________________________________________________ -->
				1175	<div class="doc_subsubsection"> <a name="t_floating">Floating Point Types</a> </div>
				1176
				1177	<div class="doc_text">
				1178	<table>
				1179	<tbody>
				1180	<tr><th>Type</th><th>Description</th></tr>
				1181	<tr><td><tt>float</tt></td><td>32-bit floating point value</td></tr>
				1182	<tr><td><tt>double</tt></td><td>64-bit floating point value</td></tr>
				1183	<tr><td><tt>fp128</tt></td><td>128-bit floating point value (112-bit mantissa)</td></tr>
				1184	<tr><td><tt>x86_fp80</tt></td><td>80-bit floating point value (X87)</td></tr>
				1185	<tr><td><tt>ppc_fp128</tt></td><td>128-bit floating point value (two 64-bits)</td></tr>
				1186	</tbody>
				1187	</table>
				1188	</div>
				1189
				1190	<!-- _______________________________________________________________________ -->
				1191	<div class="doc_subsubsection"> <a name="t_void">Void Type</a> </div>
				1192
				1193	<div class="doc_text">
				1194	<h5>Overview:</h5>
				1195	<p>The void type does not represent any value and has no size.</p>
				1196
				1197	<h5>Syntax:</h5>
				1198
				1199	<pre>
				1200	void
				1201	</pre>
				1202	</div>
				1203
				1204	<!-- _______________________________________________________________________ -->
				1205	<div class="doc_subsubsection"> <a name="t_label">Label Type</a> </div>
				1206
				1207	<div class="doc_text">
				1208	<h5>Overview:</h5>
				1209	<p>The label type represents code labels.</p>
				1210
				1211	<h5>Syntax:</h5>
				1212
				1213	<pre>
				1214	label
				1215	</pre>
				1216	</div>
				1217
				1218
				1219	<!-- ======================================================================= -->
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1220	<div class="doc_subsection"> <a name="t_derived">Derived Types</a> </div>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1221
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1222	<div class="doc_text">
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1223
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1224	<p>The real power in LLVM comes from the derived types in the system.
				1225	This is what allows a programmer to represent arrays, functions,
				1226	pointers, and other useful types. Note that these derived types may be
				1227	recursive: For example, it is possible to have a two dimensional array.</p>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1228
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1229	</div>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1230
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1231	<!-- _______________________________________________________________________ -->
Reid Spencer	138249b	2007-05-16 18:44:01 +0000	[diff] [blame]	1232	<div class="doc_subsubsection"> <a name="t_integer">Integer Type</a> </div>
				1233
				1234	<div class="doc_text">
				1235
				1236	<h5>Overview:</h5>
				1237	<p>The integer type is a very simple derived type that simply specifies an
				1238	arbitrary bit width for the integer type desired. Any bit width from 1 bit to
				1239	2^23-1 (about 8 million) can be specified.</p>
				1240
				1241	<h5>Syntax:</h5>
				1242
				1243	<pre>
				1244	iN
				1245	</pre>
				1246
				1247	<p>The number of bits the integer will occupy is specified by the <tt>N</tt>
				1248	value.</p>
				1249
				1250	<h5>Examples:</h5>
				1251	<table class="layout">
Chris Lattner	9a2e3cb	2007-12-18 06:18:21 +0000	[diff] [blame]	1252	<tbody>
				1253	<tr>
				1254	<td><tt>i1</tt></td>
				1255	<td>a single-bit integer.</td>
				1256	</tr><tr>
				1257	<td><tt>i32</tt></td>
				1258	<td>a 32-bit integer.</td>
				1259	</tr><tr>
				1260	<td><tt>i1942652</tt></td>
				1261	<td>a really big integer of over 1 million bits.</td>
Reid Spencer	138249b	2007-05-16 18:44:01 +0000	[diff] [blame]	1262	</tr>
Chris Lattner	9a2e3cb	2007-12-18 06:18:21 +0000	[diff] [blame]	1263	</tbody>
Reid Spencer	138249b	2007-05-16 18:44:01 +0000	[diff] [blame]	1264	</table>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	1265	</div>
Reid Spencer	138249b	2007-05-16 18:44:01 +0000	[diff] [blame]	1266
				1267	<!-- _______________________________________________________________________ -->
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1268	<div class="doc_subsubsection"> <a name="t_array">Array Type</a> </div>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1269
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1270	<div class="doc_text">
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1271
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1272	<h5>Overview:</h5>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1273
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1274	<p>The array type is a very simple derived type that arranges elements
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1275	sequentially in memory. The array type requires a size (number of
				1276	elements) and an underlying data type.</p>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1277
Chris Lattner	590645f	2002-04-14 06:13:44 +0000	[diff] [blame]	1278	<h5>Syntax:</h5>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1279
				1280	<pre>
				1281	[<# elements> x <elementtype>]
				1282	</pre>
				1283
John Criswell	02fdc6f	2005-05-12 16:52:32 +0000	[diff] [blame]	1284	<p>The number of elements is a constant integer value; elementtype may
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1285	be any type with a size.</p>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1286
Chris Lattner	590645f	2002-04-14 06:13:44 +0000	[diff] [blame]	1287	<h5>Examples:</h5>
Reid Spencer	c3c4c4f	2004-11-01 08:19:36 +0000	[diff] [blame]	1288	<table class="layout">
				1289	<tr class="layout">
Chris Lattner	747359f	2007-12-19 05:04:11 +0000	[diff] [blame]	1290	<td class="left"><tt>[40 x i32]</tt></td>
				1291	<td class="left">Array of 40 32-bit integer values.</td>
				1292	</tr>
				1293	<tr class="layout">
				1294	<td class="left"><tt>[41 x i32]</tt></td>
				1295	<td class="left">Array of 41 32-bit integer values.</td>
				1296	</tr>
				1297	<tr class="layout">
				1298	<td class="left"><tt>[4 x i8]</tt></td>
				1299	<td class="left">Array of 4 8-bit integer values.</td>
Reid Spencer	c3c4c4f	2004-11-01 08:19:36 +0000	[diff] [blame]	1300	</tr>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1301	</table>
Reid Spencer	c3c4c4f	2004-11-01 08:19:36 +0000	[diff] [blame]	1302	<p>Here are some examples of multidimensional arrays:</p>
				1303	<table class="layout">
				1304	<tr class="layout">
Chris Lattner	747359f	2007-12-19 05:04:11 +0000	[diff] [blame]	1305	<td class="left"><tt>[3 x [4 x i32]]</tt></td>
				1306	<td class="left">3x4 array of 32-bit integer values.</td>
				1307	</tr>
				1308	<tr class="layout">
				1309	<td class="left"><tt>[12 x [10 x float]]</tt></td>
				1310	<td class="left">12x10 array of single precision floating point values.</td>
				1311	</tr>
				1312	<tr class="layout">
				1313	<td class="left"><tt>[2 x [3 x [4 x i16]]]</tt></td>
				1314	<td class="left">2x3x4 array of 16-bit integer values.</td>
Reid Spencer	c3c4c4f	2004-11-01 08:19:36 +0000	[diff] [blame]	1315	</tr>
				1316	</table>
Chris Lattner	c0ad71e	2005-06-24 17:22:57 +0000	[diff] [blame]	1317
John Criswell	4c0cf7f	2005-10-24 16:17:18 +0000	[diff] [blame]	1318	<p>Note that 'variable sized arrays' can be implemented in LLVM with a zero
				1319	length array. Normally, accesses past the end of an array are undefined in
Chris Lattner	c0ad71e	2005-06-24 17:22:57 +0000	[diff] [blame]	1320	LLVM (e.g. it is illegal to access the 5th element of a 3 element array).
				1321	As a special case, however, zero length arrays are recognized to be variable
				1322	length. This allows implementation of 'pascal style arrays' with the LLVM
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	1323	type "{ i32, [0 x float]}", for example.</p>
Chris Lattner	c0ad71e	2005-06-24 17:22:57 +0000	[diff] [blame]	1324
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1325	</div>
Reid Spencer	c3c4c4f	2004-11-01 08:19:36 +0000	[diff] [blame]	1326
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1327	<!-- _______________________________________________________________________ -->
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1328	<div class="doc_subsubsection"> <a name="t_function">Function Type</a> </div>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1329	<div class="doc_text">
Chris Lattner	da508ac	2008-04-23 04:59:35 +0000	[diff] [blame]	1330
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1331	<h5>Overview:</h5>
Chris Lattner	da508ac	2008-04-23 04:59:35 +0000	[diff] [blame]	1332
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1333	<p>The function type can be thought of as a function signature. It
Devang Patel	e3dfc1c	2008-03-24 05:35:41 +0000	[diff] [blame]	1334	consists of a return type and a list of formal parameter types. The
Chris Lattner	da508ac	2008-04-23 04:59:35 +0000	[diff] [blame]	1335	return type of a function type is a scalar type, a void type, or a struct type.
Devang Patel	9c1f8b1	2008-03-24 20:52:42 +0000	[diff] [blame]	1336	If the return type is a struct type then all struct elements must be of first
Chris Lattner	da508ac	2008-04-23 04:59:35 +0000	[diff] [blame]	1337	class types, and the struct must have at least one element.</p>
Devang Patel	d6cff51	2008-03-10 20:49:15 +0000	[diff] [blame]	1338
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1339	<h5>Syntax:</h5>
Chris Lattner	da508ac	2008-04-23 04:59:35 +0000	[diff] [blame]	1340
				1341	<pre>
				1342	<returntype list> (<parameter list>)
				1343	</pre>
				1344
John Criswell	4c0cf7f	2005-10-24 16:17:18 +0000	[diff] [blame]	1345	<p>...where '<tt><parameter list></tt>' is a comma-separated list of type
Misha Brukman	20f9a62	2004-08-12 20:16:08 +0000	[diff] [blame]	1346	specifiers. Optionally, the parameter list may include a type <tt>...</tt>,
Chris Lattner	5ed6061	2003-09-03 00:41:47 +0000	[diff] [blame]	1347	which indicates that the function takes a variable number of arguments.
				1348	Variable argument functions can access their arguments with the <a
Devang Patel	d6cff51	2008-03-10 20:49:15 +0000	[diff] [blame]	1349	href="#int_varargs">variable argument handling intrinsic</a> functions.
				1350	'<tt><returntype list></tt>' is a comma-separated list of
				1351	<a href="#t_firstclass">first class</a> type specifiers.</p>
Chris Lattner	da508ac	2008-04-23 04:59:35 +0000	[diff] [blame]	1352
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1353	<h5>Examples:</h5>
Reid Spencer	c3c4c4f	2004-11-01 08:19:36 +0000	[diff] [blame]	1354	<table class="layout">
				1355	<tr class="layout">
Reid Spencer	58c0871	2006-12-31 07:18:34 +0000	[diff] [blame]	1356	<td class="left"><tt>i32 (i32)</tt></td>
				1357	<td class="left">function taking an <tt>i32</tt>, returning an <tt>i32</tt>
Reid Spencer	c3c4c4f	2004-11-01 08:19:36 +0000	[diff] [blame]	1358	</td>
Reid Spencer	58c0871	2006-12-31 07:18:34 +0000	[diff] [blame]	1359	</tr><tr class="layout">
Reid Spencer	314e1cb	2007-07-19 23:13:04 +0000	[diff] [blame]	1360	<td class="left"><tt>float (i16 signext, i32 )
Reid Spencer	655dcc6	2006-12-31 07:20:23 +0000	[diff] [blame]	1361	</tt></td>
Reid Spencer	58c0871	2006-12-31 07:18:34 +0000	[diff] [blame]	1362	<td class="left"><a href="#t_pointer">Pointer</a> to a function that takes
				1363	an <tt>i16</tt> that should be sign extended and a
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	1364	<a href="#t_pointer">pointer</a> to <tt>i32</tt>, returning
Reid Spencer	58c0871	2006-12-31 07:18:34 +0000	[diff] [blame]	1365	<tt>float</tt>.
				1366	</td>
				1367	</tr><tr class="layout">
				1368	<td class="left"><tt>i32 (i8*, ...)</tt></td>
				1369	<td class="left">A vararg function that takes at least one
Reid Spencer	3e628eb9	2007-01-04 16:43:23 +0000	[diff] [blame]	1370	<a href="#t_pointer">pointer</a> to <tt>i8 </tt> (char in C),
Reid Spencer	58c0871	2006-12-31 07:18:34 +0000	[diff] [blame]	1371	which returns an integer. This is the signature for <tt>printf</tt> in
				1372	LLVM.
Reid Spencer	c3c4c4f	2004-11-01 08:19:36 +0000	[diff] [blame]	1373	</td>
Devang Patel	e3dfc1c	2008-03-24 05:35:41 +0000	[diff] [blame]	1374	</tr><tr class="layout">
				1375	<td class="left"><tt>{i32, i32} (i32)</tt></td>
Devang Patel	8dec6c2	2008-03-24 18:10:52 +0000	[diff] [blame]	1376	<td class="left">A function taking an <tt>i32></tt>, returning two
				1377	<tt> i32 </tt> values as an aggregate of type <tt>{ i32, i32 }</tt>
Devang Patel	e3dfc1c	2008-03-24 05:35:41 +0000	[diff] [blame]	1378	</td>
Reid Spencer	c3c4c4f	2004-11-01 08:19:36 +0000	[diff] [blame]	1379	</tr>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1380	</table>
Misha Brukman	c501f55	2004-03-01 17:47:27 +0000	[diff] [blame]	1381
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1382	</div>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1383	<!-- _______________________________________________________________________ -->
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1384	<div class="doc_subsubsection"> <a name="t_struct">Structure Type</a> </div>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1385	<div class="doc_text">
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1386	<h5>Overview:</h5>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1387	<p>The structure type is used to represent a collection of data members
				1388	together in memory. The packing of the field types is defined to match
				1389	the ABI of the underlying processor. The elements of a structure may
				1390	be any type that has a size.</p>
				1391	<p>Structures are accessed using '<tt><a href="#i_load">load</a></tt>
				1392	and '<tt><a href="#i_store">store</a></tt>' by getting a pointer to a
				1393	field with the '<tt><a href="#i_getelementptr">getelementptr</a></tt>'
				1394	instruction.</p>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1395	<h5>Syntax:</h5>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1396	<pre> { <type list> }<br></pre>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1397	<h5>Examples:</h5>
Reid Spencer	c3c4c4f	2004-11-01 08:19:36 +0000	[diff] [blame]	1398	<table class="layout">
				1399	<tr class="layout">
Jeff Cohen	5819f18	2007-04-22 01:17:39 +0000	[diff] [blame]	1400	<td class="left"><tt>{ i32, i32, i32 }</tt></td>
				1401	<td class="left">A triple of three <tt>i32</tt> values</td>
				1402	</tr><tr class="layout">
				1403	<td class="left"><tt>{ float, i32 (i32) * }</tt></td>
				1404	<td class="left">A pair, where the first element is a <tt>float</tt> and the
				1405	second element is a <a href="#t_pointer">pointer</a> to a
				1406	<a href="#t_function">function</a> that takes an <tt>i32</tt>, returning
				1407	an <tt>i32</tt>.</td>
Reid Spencer	c3c4c4f	2004-11-01 08:19:36 +0000	[diff] [blame]	1408	</tr>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1409	</table>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1410	</div>
Reid Spencer	c3c4c4f	2004-11-01 08:19:36 +0000	[diff] [blame]	1411
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1412	<!-- _______________________________________________________________________ -->
Andrew Lenharth	8df88e2	2006-12-08 17:13:00 +0000	[diff] [blame]	1413	<div class="doc_subsubsection"> <a name="t_pstruct">Packed Structure Type</a>
				1414	</div>
				1415	<div class="doc_text">
				1416	<h5>Overview:</h5>
				1417	<p>The packed structure type is used to represent a collection of data members
				1418	together in memory. There is no padding between fields. Further, the alignment
				1419	of a packed structure is 1 byte. The elements of a packed structure may
				1420	be any type that has a size.</p>
				1421	<p>Structures are accessed using '<tt><a href="#i_load">load</a></tt>
				1422	and '<tt><a href="#i_store">store</a></tt>' by getting a pointer to a
				1423	field with the '<tt><a href="#i_getelementptr">getelementptr</a></tt>'
				1424	instruction.</p>
				1425	<h5>Syntax:</h5>
				1426	<pre> < { <type list> } > <br></pre>
				1427	<h5>Examples:</h5>
				1428	<table class="layout">
				1429	<tr class="layout">
Jeff Cohen	5819f18	2007-04-22 01:17:39 +0000	[diff] [blame]	1430	<td class="left"><tt>< { i32, i32, i32 } ></tt></td>
				1431	<td class="left">A triple of three <tt>i32</tt> values</td>
				1432	</tr><tr class="layout">
Bill Wendling	b175fa4	2008-09-07 10:26:33 +0000	[diff] [blame]	1433	<td class="left">
				1434	<tt>< { float, i32 (i32)* } ></tt></td>
Jeff Cohen	5819f18	2007-04-22 01:17:39 +0000	[diff] [blame]	1435	<td class="left">A pair, where the first element is a <tt>float</tt> and the
				1436	second element is a <a href="#t_pointer">pointer</a> to a
				1437	<a href="#t_function">function</a> that takes an <tt>i32</tt>, returning
				1438	an <tt>i32</tt>.</td>
Andrew Lenharth	8df88e2	2006-12-08 17:13:00 +0000	[diff] [blame]	1439	</tr>
				1440	</table>
				1441	</div>
				1442
				1443	<!-- _______________________________________________________________________ -->
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1444	<div class="doc_subsubsection"> <a name="t_pointer">Pointer Type</a> </div>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1445	<div class="doc_text">
Chris Lattner	590645f	2002-04-14 06:13:44 +0000	[diff] [blame]	1446	<h5>Overview:</h5>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1447	<p>As in many languages, the pointer type represents a pointer or
Christopher Lamb	308121c	2007-12-11 09:31:00 +0000	[diff] [blame]	1448	reference to another object, which must live in memory. Pointer types may have
				1449	an optional address space attribute defining the target-specific numbered
				1450	address space where the pointed-to object resides. The default address space is
				1451	zero.</p>
Chris Lattner	590645f	2002-04-14 06:13:44 +0000	[diff] [blame]	1452	<h5>Syntax:</h5>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1453	<pre> <type> *<br></pre>
Chris Lattner	590645f	2002-04-14 06:13:44 +0000	[diff] [blame]	1454	<h5>Examples:</h5>
Reid Spencer	c3c4c4f	2004-11-01 08:19:36 +0000	[diff] [blame]	1455	<table class="layout">
				1456	<tr class="layout">
Chris Lattner	747359f	2007-12-19 05:04:11 +0000	[diff] [blame]	1457	<td class="left"><tt>[4x i32]*</tt></td>
				1458	<td class="left">A <a href="#t_pointer">pointer</a> to <a
				1459	href="#t_array">array</a> of four <tt>i32</tt> values.</td>
				1460	</tr>
				1461	<tr class="layout">
				1462	<td class="left"><tt>i32 (i32 ) </tt></td>
				1463	<td class="left"> A <a href="#t_pointer">pointer</a> to a <a
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	1464	href="#t_function">function</a> that takes an <tt>i32*</tt>, returning an
Chris Lattner	747359f	2007-12-19 05:04:11 +0000	[diff] [blame]	1465	<tt>i32</tt>.</td>
				1466	</tr>
				1467	<tr class="layout">
				1468	<td class="left"><tt>i32 addrspace(5)*</tt></td>
				1469	<td class="left">A <a href="#t_pointer">pointer</a> to an <tt>i32</tt> value
				1470	that resides in address space #5.</td>
Reid Spencer	c3c4c4f	2004-11-01 08:19:36 +0000	[diff] [blame]	1471	</tr>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1472	</table>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1473	</div>
Reid Spencer	c3c4c4f	2004-11-01 08:19:36 +0000	[diff] [blame]	1474
Chris Lattner	c8cb695	2004-08-12 19:12:28 +0000	[diff] [blame]	1475	<!-- _______________________________________________________________________ -->
Reid Spencer	404a325	2007-02-15 03:07:05 +0000	[diff] [blame]	1476	<div class="doc_subsubsection"> <a name="t_vector">Vector Type</a> </div>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1477	<div class="doc_text">
Chris Lattner	37b6b09	2005-04-25 17:34:15 +0000	[diff] [blame]	1478
Chris Lattner	c8cb695	2004-08-12 19:12:28 +0000	[diff] [blame]	1479	<h5>Overview:</h5>
Chris Lattner	37b6b09	2005-04-25 17:34:15 +0000	[diff] [blame]	1480
Reid Spencer	404a325	2007-02-15 03:07:05 +0000	[diff] [blame]	1481	<p>A vector type is a simple derived type that represents a vector
				1482	of elements. Vector types are used when multiple primitive data
Chris Lattner	c8cb695	2004-08-12 19:12:28 +0000	[diff] [blame]	1483	are operated in parallel using a single instruction (SIMD).
Reid Spencer	404a325	2007-02-15 03:07:05 +0000	[diff] [blame]	1484	A vector type requires a size (number of
Chris Lattner	330ce69	2005-11-10 01:44:22 +0000	[diff] [blame]	1485	elements) and an underlying primitive data type. Vectors must have a power
Reid Spencer	404a325	2007-02-15 03:07:05 +0000	[diff] [blame]	1486	of two length (1, 2, 4, 8, 16 ...). Vector types are
Chris Lattner	c8cb695	2004-08-12 19:12:28 +0000	[diff] [blame]	1487	considered <a href="#t_firstclass">first class</a>.</p>
Chris Lattner	37b6b09	2005-04-25 17:34:15 +0000	[diff] [blame]	1488
Chris Lattner	c8cb695	2004-08-12 19:12:28 +0000	[diff] [blame]	1489	<h5>Syntax:</h5>
Chris Lattner	37b6b09	2005-04-25 17:34:15 +0000	[diff] [blame]	1490
				1491	<pre>
				1492	< <# elements> x <elementtype> >
				1493	</pre>
				1494
John Criswell	4a3327e	2005-05-13 22:25:59 +0000	[diff] [blame]	1495	<p>The number of elements is a constant integer value; elementtype may
Chris Lattner	c0f423a	2007-01-15 01:54:13 +0000	[diff] [blame]	1496	be any integer or floating point type.</p>
Chris Lattner	37b6b09	2005-04-25 17:34:15 +0000	[diff] [blame]	1497
Chris Lattner	c8cb695	2004-08-12 19:12:28 +0000	[diff] [blame]	1498	<h5>Examples:</h5>
Chris Lattner	37b6b09	2005-04-25 17:34:15 +0000	[diff] [blame]	1499
Reid Spencer	c3c4c4f	2004-11-01 08:19:36 +0000	[diff] [blame]	1500	<table class="layout">
				1501	<tr class="layout">
Chris Lattner	747359f	2007-12-19 05:04:11 +0000	[diff] [blame]	1502	<td class="left"><tt><4 x i32></tt></td>
				1503	<td class="left">Vector of 4 32-bit integer values.</td>
				1504	</tr>
				1505	<tr class="layout">
				1506	<td class="left"><tt><8 x float></tt></td>
				1507	<td class="left">Vector of 8 32-bit floating-point values.</td>
				1508	</tr>
				1509	<tr class="layout">
				1510	<td class="left"><tt><2 x i64></tt></td>
				1511	<td class="left">Vector of 2 64-bit integer values.</td>
Reid Spencer	c3c4c4f	2004-11-01 08:19:36 +0000	[diff] [blame]	1512	</tr>
				1513	</table>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1514	</div>
				1515
Chris Lattner	37b6b09	2005-04-25 17:34:15 +0000	[diff] [blame]	1516	<!-- _______________________________________________________________________ -->
				1517	<div class="doc_subsubsection"> <a name="t_opaque">Opaque Type</a> </div>
				1518	<div class="doc_text">
				1519
				1520	<h5>Overview:</h5>
				1521
				1522	<p>Opaque types are used to represent unknown types in the system. This
Gordon Henriksen	a699c4d	2007-10-14 00:34:53 +0000	[diff] [blame]	1523	corresponds (for example) to the C notion of a forward declared structure type.
Chris Lattner	37b6b09	2005-04-25 17:34:15 +0000	[diff] [blame]	1524	In LLVM, opaque types can eventually be resolved to any type (not just a
				1525	structure type).</p>
				1526
				1527	<h5>Syntax:</h5>
				1528
				1529	<pre>
				1530	opaque
				1531	</pre>
				1532
				1533	<h5>Examples:</h5>
				1534
				1535	<table class="layout">
				1536	<tr class="layout">
Chris Lattner	747359f	2007-12-19 05:04:11 +0000	[diff] [blame]	1537	<td class="left"><tt>opaque</tt></td>
				1538	<td class="left">An opaque type.</td>
Chris Lattner	37b6b09	2005-04-25 17:34:15 +0000	[diff] [blame]	1539	</tr>
				1540	</table>
				1541	</div>
				1542
				1543
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1544	<!-- *********************************************************************** -->
				1545	<div class="doc_section"> <a name="constants">Constants</a> </div>
				1546	<!-- *********************************************************************** -->
				1547
				1548	<div class="doc_text">
				1549
				1550	<p>LLVM has several different basic types of constants. This section describes
				1551	them all and their syntax.</p>
				1552
				1553	</div>
				1554
				1555	<!-- ======================================================================= -->
Reid Spencer	8f08d80	2004-12-09 18:02:53 +0000	[diff] [blame]	1556	<div class="doc_subsection"><a name="simpleconstants">Simple Constants</a></div>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1557
				1558	<div class="doc_text">
				1559
				1560	<dl>
				1561	<dt><b>Boolean constants</b></dt>
				1562
				1563	<dd>The two strings '<tt>true</tt>' and '<tt>false</tt>' are both valid
Reid Spencer	36a1542	2007-01-12 03:35:51 +0000	[diff] [blame]	1564	constants of the <tt><a href="#t_primitive">i1</a></tt> type.
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1565	</dd>
				1566
				1567	<dt><b>Integer constants</b></dt>
				1568
Reid Spencer	8f08d80	2004-12-09 18:02:53 +0000	[diff] [blame]	1569	<dd>Standard integers (such as '4') are constants of the <a
Reid Spencer	3e628eb9	2007-01-04 16:43:23 +0000	[diff] [blame]	1570	href="#t_integer">integer</a> type. Negative numbers may be used with
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1571	integer types.
				1572	</dd>
				1573
				1574	<dt><b>Floating point constants</b></dt>
				1575
				1576	<dd>Floating point constants use standard decimal notation (e.g. 123.421),
				1577	exponential notation (e.g. 1.23421e+2), or a more precise hexadecimal
Chris Lattner	1429e6f	2008-04-01 18:45:27 +0000	[diff] [blame]	1578	notation (see below). The assembler requires the exact decimal value of
				1579	a floating-point constant. For example, the assembler accepts 1.25 but
				1580	rejects 1.3 because 1.3 is a repeating decimal in binary. Floating point
				1581	constants must have a <a href="#t_floating">floating point</a> type. </dd>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1582
				1583	<dt><b>Null pointer constants</b></dt>
				1584
John Criswell	dfe6a86	2004-12-10 15:51:16 +0000	[diff] [blame]	1585	<dd>The identifier '<tt>null</tt>' is recognized as a null pointer constant
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1586	and must be of <a href="#t_pointer">pointer type</a>.</dd>
				1587
				1588	</dl>
				1589
John Criswell	dfe6a86	2004-12-10 15:51:16 +0000	[diff] [blame]	1590	<p>The one non-intuitive notation for constants is the optional hexadecimal form
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1591	of floating point constants. For example, the form '<tt>double
				1592	0x432ff973cafa8000</tt>' is equivalent to (but harder to read than) '<tt>double
				1593	4.5e+15</tt>'. The only time hexadecimal floating point constants are required
Reid Spencer	8f08d80	2004-12-09 18:02:53 +0000	[diff] [blame]	1594	(and the only time that they are generated by the disassembler) is when a
				1595	floating point constant must be emitted but it cannot be represented as a
				1596	decimal floating point number. For example, NaN's, infinities, and other
				1597	special values are represented in their IEEE hexadecimal format so that
				1598	assembly and disassembly do not cause any bits to change in the constants.</p>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1599
				1600	</div>
				1601
				1602	<!-- ======================================================================= -->
				1603	<div class="doc_subsection"><a name="aggregateconstants">Aggregate Constants</a>
				1604	</div>
				1605
				1606	<div class="doc_text">
Chris Lattner	455fc8c	2005-03-07 22:13:59 +0000	[diff] [blame]	1607	<p>Aggregate constants arise from aggregation of simple constants
				1608	and smaller aggregate constants.</p>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1609
				1610	<dl>
				1611	<dt><b>Structure constants</b></dt>
				1612
				1613	<dd>Structure constants are represented with notation similar to structure
				1614	type definitions (a comma separated list of elements, surrounded by braces
Chris Lattner	bea1117	2007-12-25 20:34:52 +0000	[diff] [blame]	1615	(<tt>{}</tt>)). For example: "<tt>{ i32 4, float 17.0, i32* @G }</tt>",
				1616	where "<tt>@G</tt>" is declared as "<tt>@G = external global i32</tt>". Structure constants
Chris Lattner	455fc8c	2005-03-07 22:13:59 +0000	[diff] [blame]	1617	must have <a href="#t_struct">structure type</a>, and the number and
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1618	types of elements must match those specified by the type.
				1619	</dd>
				1620
				1621	<dt><b>Array constants</b></dt>
				1622
				1623	<dd>Array constants are represented with notation similar to array type
				1624	definitions (a comma separated list of elements, surrounded by square brackets
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	1625	(<tt>[]</tt>)). For example: "<tt>[ i32 42, i32 11, i32 74 ]</tt>". Array
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1626	constants must have <a href="#t_array">array type</a>, and the number and
				1627	types of elements must match those specified by the type.
				1628	</dd>
				1629
Reid Spencer	404a325	2007-02-15 03:07:05 +0000	[diff] [blame]	1630	<dt><b>Vector constants</b></dt>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1631
Reid Spencer	404a325	2007-02-15 03:07:05 +0000	[diff] [blame]	1632	<dd>Vector constants are represented with notation similar to vector type
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1633	definitions (a comma separated list of elements, surrounded by
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	1634	less-than/greater-than's (<tt><></tt>)). For example: "<tt>< i32 42,
Jeff Cohen	5819f18	2007-04-22 01:17:39 +0000	[diff] [blame]	1635	i32 11, i32 74, i32 100 ></tt>". Vector constants must have <a
Reid Spencer	404a325	2007-02-15 03:07:05 +0000	[diff] [blame]	1636	href="#t_vector">vector type</a>, and the number and types of elements must
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1637	match those specified by the type.
				1638	</dd>
				1639
				1640	<dt><b>Zero initialization</b></dt>
				1641
				1642	<dd>The string '<tt>zeroinitializer</tt>' can be used to zero initialize a
				1643	value to zero of <em>any</em> type, including scalar and aggregate types.
				1644	This is often used to avoid having to print large zero initializers (e.g. for
John Criswell	4c0cf7f	2005-10-24 16:17:18 +0000	[diff] [blame]	1645	large arrays) and is always exactly equivalent to using explicit zero
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1646	initializers.
				1647	</dd>
				1648	</dl>
				1649
				1650	</div>
				1651
				1652	<!-- ======================================================================= -->
				1653	<div class="doc_subsection">
				1654	<a name="globalconstants">Global Variable and Function Addresses</a>
				1655	</div>
				1656
				1657	<div class="doc_text">
				1658
				1659	<p>The addresses of <a href="#globalvars">global variables</a> and <a
				1660	href="#functionstructure">functions</a> are always implicitly valid (link-time)
John Criswell	dfe6a86	2004-12-10 15:51:16 +0000	[diff] [blame]	1661	constants. These constants are explicitly referenced when the <a
				1662	href="#identifiers">identifier for the global</a> is used and always have <a
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1663	href="#t_pointer">pointer</a> type. For example, the following is a legal LLVM
				1664	file:</p>
				1665
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	1666	<div class="doc_code">
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1667	<pre>
Chris Lattner	00538a1	2007-06-06 18:28:13 +0000	[diff] [blame]	1668	@X = global i32 17
				1669	@Y = global i32 42
				1670	@Z = global [2 x i32] [ i32 @X, i32* @Y ]
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1671	</pre>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	1672	</div>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1673
				1674	</div>
				1675
				1676	<!-- ======================================================================= -->
Reid Spencer	641f5c9	2004-12-09 18:13:12 +0000	[diff] [blame]	1677	<div class="doc_subsection"><a name="undefvalues">Undefined Values</a></div>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1678	<div class="doc_text">
Reid Spencer	641f5c9	2004-12-09 18:13:12 +0000	[diff] [blame]	1679	<p>The string '<tt>undef</tt>' is recognized as a type-less constant that has
John Criswell	4a3327e	2005-05-13 22:25:59 +0000	[diff] [blame]	1680	no specific value. Undefined values may be of any type and be used anywhere
Reid Spencer	641f5c9	2004-12-09 18:13:12 +0000	[diff] [blame]	1681	a constant is permitted.</p>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1682
Reid Spencer	641f5c9	2004-12-09 18:13:12 +0000	[diff] [blame]	1683	<p>Undefined values indicate to the compiler that the program is well defined
				1684	no matter what value is used, giving the compiler more freedom to optimize.
				1685	</p>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1686	</div>
				1687
				1688	<!-- ======================================================================= -->
				1689	<div class="doc_subsection"><a name="constantexprs">Constant Expressions</a>
				1690	</div>
				1691
				1692	<div class="doc_text">
				1693
				1694	<p>Constant expressions are used to allow expressions involving other constants
				1695	to be used as constants. Constant expressions may be of any <a
John Criswell	4a3327e	2005-05-13 22:25:59 +0000	[diff] [blame]	1696	href="#t_firstclass">first class</a> type and may involve any LLVM operation
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1697	that does not have side effects (e.g. load and call are not supported). The
				1698	following is the syntax for constant expressions:</p>
				1699
				1700	<dl>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	1701	<dt><b><tt>trunc ( CST to TYPE )</tt></b></dt>
				1702	<dd>Truncate a constant to another type. The bit size of CST must be larger
Chris Lattner	c0f423a	2007-01-15 01:54:13 +0000	[diff] [blame]	1703	than the bit size of TYPE. Both types must be integers.</dd>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1704
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	1705	<dt><b><tt>zext ( CST to TYPE )</tt></b></dt>
				1706	<dd>Zero extend a constant to another type. The bit size of CST must be
Chris Lattner	c0f423a	2007-01-15 01:54:13 +0000	[diff] [blame]	1707	smaller or equal to the bit size of TYPE. Both types must be integers.</dd>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	1708
				1709	<dt><b><tt>sext ( CST to TYPE )</tt></b></dt>
				1710	<dd>Sign extend a constant to another type. The bit size of CST must be
Chris Lattner	c0f423a	2007-01-15 01:54:13 +0000	[diff] [blame]	1711	smaller or equal to the bit size of TYPE. Both types must be integers.</dd>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	1712
				1713	<dt><b><tt>fptrunc ( CST to TYPE )</tt></b></dt>
				1714	<dd>Truncate a floating point constant to another floating point type. The
				1715	size of CST must be larger than the size of TYPE. Both types must be
				1716	floating point.</dd>
				1717
				1718	<dt><b><tt>fpext ( CST to TYPE )</tt></b></dt>
				1719	<dd>Floating point extend a constant to another type. The size of CST must be
				1720	smaller or equal to the size of TYPE. Both types must be floating point.</dd>
				1721
Reid Spencer	753163d	2007-07-31 14:40:14 +0000	[diff] [blame]	1722	<dt><b><tt>fptoui ( CST to TYPE )</tt></b></dt>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	1723	<dd>Convert a floating point constant to the corresponding unsigned integer
Nate Begeman	d4d45c2	2007-11-17 03:58:34 +0000	[diff] [blame]	1724	constant. TYPE must be a scalar or vector integer type. CST must be of scalar
				1725	or vector floating point type. Both CST and TYPE must be scalars, or vectors
				1726	of the same number of elements. If the value won't fit in the integer type,
				1727	the results are undefined.</dd>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	1728
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	1729	<dt><b><tt>fptosi ( CST to TYPE )</tt></b></dt>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	1730	<dd>Convert a floating point constant to the corresponding signed integer
Nate Begeman	d4d45c2	2007-11-17 03:58:34 +0000	[diff] [blame]	1731	constant. TYPE must be a scalar or vector integer type. CST must be of scalar
				1732	or vector floating point type. Both CST and TYPE must be scalars, or vectors
				1733	of the same number of elements. If the value won't fit in the integer type,
				1734	the results are undefined.</dd>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	1735
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	1736	<dt><b><tt>uitofp ( CST to TYPE )</tt></b></dt>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	1737	<dd>Convert an unsigned integer constant to the corresponding floating point
Nate Begeman	d4d45c2	2007-11-17 03:58:34 +0000	[diff] [blame]	1738	constant. TYPE must be a scalar or vector floating point type. CST must be of
				1739	scalar or vector integer type. Both CST and TYPE must be scalars, or vectors
				1740	of the same number of elements. If the value won't fit in the floating point
				1741	type, the results are undefined.</dd>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	1742
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	1743	<dt><b><tt>sitofp ( CST to TYPE )</tt></b></dt>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	1744	<dd>Convert a signed integer constant to the corresponding floating point
Nate Begeman	d4d45c2	2007-11-17 03:58:34 +0000	[diff] [blame]	1745	constant. TYPE must be a scalar or vector floating point type. CST must be of
				1746	scalar or vector integer type. Both CST and TYPE must be scalars, or vectors
				1747	of the same number of elements. If the value won't fit in the floating point
				1748	type, the results are undefined.</dd>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	1749
Reid Spencer	5b95064	2006-11-11 23:08:07 +0000	[diff] [blame]	1750	<dt><b><tt>ptrtoint ( CST to TYPE )</tt></b></dt>
				1751	<dd>Convert a pointer typed constant to the corresponding integer constant
				1752	TYPE must be an integer type. CST must be of pointer type. The CST value is
				1753	zero extended, truncated, or unchanged to make it fit in TYPE.</dd>
				1754
				1755	<dt><b><tt>inttoptr ( CST to TYPE )</tt></b></dt>
				1756	<dd>Convert a integer constant to a pointer constant. TYPE must be a
				1757	pointer type. CST must be of integer type. The CST value is zero extended,
				1758	truncated, or unchanged to make it fit in a pointer size. This one is
				1759	<i>really</i> dangerous!</dd>
				1760
				1761	<dt><b><tt>bitcast ( CST to TYPE )</tt></b></dt>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	1762	<dd>Convert a constant, CST, to another TYPE. The size of CST and TYPE must be
				1763	identical (same number of bits). The conversion is done as if the CST value
				1764	was stored to memory and read back as TYPE. In other words, no bits change
Reid Spencer	5b95064	2006-11-11 23:08:07 +0000	[diff] [blame]	1765	with this operator, just the type. This can be used for conversion of
Reid Spencer	404a325	2007-02-15 03:07:05 +0000	[diff] [blame]	1766	vector types to any other type, as long as they have the same bit width. For
Dan Gohman	c05dca9	2008-09-08 16:45:59 +0000	[diff] [blame]	1767	pointers it is only valid to cast to another pointer type. It is not valid
				1768	to bitcast to or from an aggregate type.
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	1769	</dd>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1770
				1771	<dt><b><tt>getelementptr ( CSTPTR, IDX0, IDX1, ... )</tt></b></dt>
				1772
				1773	<dd>Perform the <a href="#i_getelementptr">getelementptr operation</a> on
				1774	constants. As with the <a href="#i_getelementptr">getelementptr</a>
				1775	instruction, the index list may have zero or more indexes, which are required
				1776	to make sense for the type of "CSTPTR".</dd>
				1777
Robert Bocchino	7e97a6d	2006-01-10 19:31:34 +0000	[diff] [blame]	1778	<dt><b><tt>select ( COND, VAL1, VAL2 )</tt></b></dt>
				1779
				1780	<dd>Perform the <a href="#i_select">select operation</a> on
Reid Spencer	9965ee7	2006-12-04 19:23:19 +0000	[diff] [blame]	1781	constants.</dd>
				1782
				1783	<dt><b><tt>icmp COND ( VAL1, VAL2 )</tt></b></dt>
				1784	<dd>Performs the <a href="#i_icmp">icmp operation</a> on constants.</dd>
				1785
				1786	<dt><b><tt>fcmp COND ( VAL1, VAL2 )</tt></b></dt>
				1787	<dd>Performs the <a href="#i_fcmp">fcmp operation</a> on constants.</dd>
Robert Bocchino	7e97a6d	2006-01-10 19:31:34 +0000	[diff] [blame]	1788
Nate Begeman	d219570	2008-05-12 19:01:56 +0000	[diff] [blame]	1789	<dt><b><tt>vicmp COND ( VAL1, VAL2 )</tt></b></dt>
				1790	<dd>Performs the <a href="#i_vicmp">vicmp operation</a> on constants.</dd>
				1791
				1792	<dt><b><tt>vfcmp COND ( VAL1, VAL2 )</tt></b></dt>
				1793	<dd>Performs the <a href="#i_vfcmp">vfcmp operation</a> on constants.</dd>
				1794
Robert Bocchino	7e97a6d	2006-01-10 19:31:34 +0000	[diff] [blame]	1795	<dt><b><tt>extractelement ( VAL, IDX )</tt></b></dt>
				1796
				1797	<dd>Perform the <a href="#i_extractelement">extractelement
				1798	operation</a> on constants.
				1799
Robert Bocchino	f72fdfe	2006-01-15 20:48:27 +0000	[diff] [blame]	1800	<dt><b><tt>insertelement ( VAL, ELT, IDX )</tt></b></dt>
				1801
				1802	<dd>Perform the <a href="#i_insertelement">insertelement
Reid Spencer	9965ee7	2006-12-04 19:23:19 +0000	[diff] [blame]	1803	operation</a> on constants.</dd>
Robert Bocchino	f72fdfe	2006-01-15 20:48:27 +0000	[diff] [blame]	1804
Chris Lattner	016a0e5	2006-04-08 00:13:41 +0000	[diff] [blame]	1805
				1806	<dt><b><tt>shufflevector ( VEC1, VEC2, IDXMASK )</tt></b></dt>
				1807
				1808	<dd>Perform the <a href="#i_shufflevector">shufflevector
Reid Spencer	9965ee7	2006-12-04 19:23:19 +0000	[diff] [blame]	1809	operation</a> on constants.</dd>
Chris Lattner	016a0e5	2006-04-08 00:13:41 +0000	[diff] [blame]	1810
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1811	<dt><b><tt>OPCODE ( LHS, RHS )</tt></b></dt>
				1812
Reid Spencer	641f5c9	2004-12-09 18:13:12 +0000	[diff] [blame]	1813	<dd>Perform the specified operation of the LHS and RHS constants. OPCODE may
				1814	be any of the <a href="#binaryops">binary</a> or <a href="#bitwiseops">bitwise
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1815	binary</a> operations. The constraints on operands are the same as those for
				1816	the corresponding instruction (e.g. no bitwise operations on floating point
John Criswell	02fdc6f	2005-05-12 16:52:32 +0000	[diff] [blame]	1817	values are allowed).</dd>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1818	</dl>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1819	</div>
Chris Lattner	b165261	2004-03-08 16:49:10 +0000	[diff] [blame]	1820
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1821	<!-- *********************************************************************** -->
Chris Lattner	98f013c	2006-01-25 23:47:57 +0000	[diff] [blame]	1822	<div class="doc_section"> <a name="othervalues">Other Values</a> </div>
				1823	<!-- *********************************************************************** -->
				1824
				1825	<!-- ======================================================================= -->
				1826	<div class="doc_subsection">
				1827	<a name="inlineasm">Inline Assembler Expressions</a>
				1828	</div>
				1829
				1830	<div class="doc_text">
				1831
				1832	<p>
				1833	LLVM supports inline assembler expressions (as opposed to <a href="#moduleasm">
				1834	Module-Level Inline Assembly</a>) through the use of a special value. This
				1835	value represents the inline assembler as a string (containing the instructions
				1836	to emit), a list of operand constraints (stored as a string), and a flag that
				1837	indicates whether or not the inline asm expression has side effects. An example
				1838	inline assembler expression is:
				1839	</p>
				1840
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	1841	<div class="doc_code">
Chris Lattner	98f013c	2006-01-25 23:47:57 +0000	[diff] [blame]	1842	<pre>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	1843	i32 (i32) asm "bswap $0", "=r,r"
Chris Lattner	98f013c	2006-01-25 23:47:57 +0000	[diff] [blame]	1844	</pre>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	1845	</div>
Chris Lattner	98f013c	2006-01-25 23:47:57 +0000	[diff] [blame]	1846
				1847	<p>
				1848	Inline assembler expressions may <b>only</b> be used as the callee operand of
				1849	a <a href="#i_call"><tt>call</tt> instruction</a>. Thus, typically we have:
				1850	</p>
				1851
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	1852	<div class="doc_code">
Chris Lattner	98f013c	2006-01-25 23:47:57 +0000	[diff] [blame]	1853	<pre>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	1854	%X = call i32 asm "<a href="#int_bswap">bswap</a> $0", "=r,r"(i32 %Y)
Chris Lattner	98f013c	2006-01-25 23:47:57 +0000	[diff] [blame]	1855	</pre>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	1856	</div>
Chris Lattner	98f013c	2006-01-25 23:47:57 +0000	[diff] [blame]	1857
				1858	<p>
				1859	Inline asms with side effects not visible in the constraint list must be marked
				1860	as having side effects. This is done through the use of the
				1861	'<tt>sideeffect</tt>' keyword, like so:
				1862	</p>
				1863
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	1864	<div class="doc_code">
Chris Lattner	98f013c	2006-01-25 23:47:57 +0000	[diff] [blame]	1865	<pre>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	1866	call void asm sideeffect "eieio", ""()
Chris Lattner	98f013c	2006-01-25 23:47:57 +0000	[diff] [blame]	1867	</pre>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	1868	</div>
Chris Lattner	98f013c	2006-01-25 23:47:57 +0000	[diff] [blame]	1869
				1870	<p>TODO: The format of the asm and constraints string still need to be
				1871	documented here. Constraints on what can be done (e.g. duplication, moving, etc
Chris Lattner	d552826	2008-10-04 18:36:02 +0000	[diff] [blame]	1872	need to be documented). This is probably best done by reference to another
				1873	document that covers inline asm from a holistic perspective.
Chris Lattner	98f013c	2006-01-25 23:47:57 +0000	[diff] [blame]	1874	</p>
				1875
				1876	</div>
				1877
				1878	<!-- *********************************************************************** -->
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1879	<div class="doc_section"> <a name="instref">Instruction Reference</a> </div>
				1880	<!-- *********************************************************************** -->
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1881
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1882	<div class="doc_text">
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1883
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1884	<p>The LLVM instruction set consists of several different
				1885	classifications of instructions: <a href="#terminators">terminator
John Criswell	4a3327e	2005-05-13 22:25:59 +0000	[diff] [blame]	1886	instructions</a>, <a href="#binaryops">binary instructions</a>,
				1887	<a href="#bitwiseops">bitwise binary instructions</a>, <a
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1888	href="#memoryops">memory instructions</a>, and <a href="#otherops">other
				1889	instructions</a>.</p>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1890
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1891	</div>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1892
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1893	<!-- ======================================================================= -->
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1894	<div class="doc_subsection"> <a name="terminators">Terminator
				1895	Instructions</a> </div>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1896
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1897	<div class="doc_text">
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1898
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1899	<p>As mentioned <a href="#functionstructure">previously</a>, every
				1900	basic block in a program ends with a "Terminator" instruction, which
				1901	indicates which block should be executed after the current block is
				1902	finished. These terminator instructions typically yield a '<tt>void</tt>'
				1903	value: they produce control flow, not values (the one exception being
				1904	the '<a href="#i_invoke"><tt>invoke</tt></a>' instruction).</p>
John Criswell	dfe6a86	2004-12-10 15:51:16 +0000	[diff] [blame]	1905	<p>There are six different terminator instructions: the '<a
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1906	href="#i_ret"><tt>ret</tt></a>' instruction, the '<a href="#i_br"><tt>br</tt></a>'
				1907	instruction, the '<a href="#i_switch"><tt>switch</tt></a>' instruction,
Chris Lattner	08b7d5b	2004-10-16 18:04:13 +0000	[diff] [blame]	1908	the '<a href="#i_invoke"><tt>invoke</tt></a>' instruction, the '<a
				1909	href="#i_unwind"><tt>unwind</tt></a>' instruction, and the '<a
				1910	href="#i_unreachable"><tt>unreachable</tt></a>' instruction.</p>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1911
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1912	</div>
Chris Lattner	74d3f82	2004-12-09 17:30:23 +0000	[diff] [blame]	1913
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1914	<!-- _______________________________________________________________________ -->
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1915	<div class="doc_subsubsection"> <a name="i_ret">'<tt>ret</tt>'
				1916	Instruction</a> </div>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1917	<div class="doc_text">
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1918	<h5>Syntax:</h5>
Dan Gohman	cc3132e	2008-10-04 19:00:07 +0000	[diff] [blame]	1919	<pre>
				1920	ret <type> <value> <i>; Return a value from a non-void function</i>
Chris Lattner	590645f	2002-04-14 06:13:44 +0000	[diff] [blame]	1921	ret void <i>; Return from void function</i>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1922	</pre>
Chris Lattner	da508ac	2008-04-23 04:59:35 +0000	[diff] [blame]	1923
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1924	<h5>Overview:</h5>
Chris Lattner	da508ac	2008-04-23 04:59:35 +0000	[diff] [blame]	1925
Dan Gohman	cc3132e	2008-10-04 19:00:07 +0000	[diff] [blame]	1926	<p>The '<tt>ret</tt>' instruction is used to return control flow (and
				1927	optionally a value) from a function back to the caller.</p>
John Criswell	417228d	2004-04-09 16:48:45 +0000	[diff] [blame]	1928	<p>There are two forms of the '<tt>ret</tt>' instruction: one that
Dan Gohman	cc3132e	2008-10-04 19:00:07 +0000	[diff] [blame]	1929	returns a value and then causes control flow, and one that just causes
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1930	control flow to occur.</p>
Chris Lattner	da508ac	2008-04-23 04:59:35 +0000	[diff] [blame]	1931
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1932	<h5>Arguments:</h5>
Chris Lattner	da508ac	2008-04-23 04:59:35 +0000	[diff] [blame]	1933
Dan Gohman	cc3132e	2008-10-04 19:00:07 +0000	[diff] [blame]	1934	<p>The '<tt>ret</tt>' instruction optionally accepts a single argument,
				1935	the return value. The type of the return value must be a
				1936	'<a href="#t_firstclass">first class</a>' type.</p>
				1937
				1938	<p>A function is not <a href="#wellformed">well formed</a> if
				1939	it it has a non-void return type and contains a '<tt>ret</tt>'
				1940	instruction with no return value or a return value with a type that
				1941	does not match its type, or if it has a void return type and contains
				1942	a '<tt>ret</tt>' instruction with a return value.</p>
Chris Lattner	da508ac	2008-04-23 04:59:35 +0000	[diff] [blame]	1943
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1944	<h5>Semantics:</h5>
Chris Lattner	da508ac	2008-04-23 04:59:35 +0000	[diff] [blame]	1945
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1946	<p>When the '<tt>ret</tt>' instruction is executed, control flow
				1947	returns back to the calling function's context. If the caller is a "<a
John Criswell	40db33f	2004-06-25 15:16:57 +0000	[diff] [blame]	1948	href="#i_call"><tt>call</tt></a>" instruction, execution continues at
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1949	the instruction after the call. If the caller was an "<a
				1950	href="#i_invoke"><tt>invoke</tt></a>" instruction, execution continues
John Criswell	02fdc6f	2005-05-12 16:52:32 +0000	[diff] [blame]	1951	at the beginning of the "normal" destination block. If the instruction
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1952	returns a value, that value shall set the call or invoke instruction's
Dan Gohman	cc3132e	2008-10-04 19:00:07 +0000	[diff] [blame]	1953	return value.
Chris Lattner	da508ac	2008-04-23 04:59:35 +0000	[diff] [blame]	1954
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1955	<h5>Example:</h5>
Chris Lattner	da508ac	2008-04-23 04:59:35 +0000	[diff] [blame]	1956
				1957	<pre>
				1958	ret i32 5 <i>; Return an integer value of 5</i>
Chris Lattner	590645f	2002-04-14 06:13:44 +0000	[diff] [blame]	1959	ret void <i>; Return from a void function</i>
Dan Gohman	cc3132e	2008-10-04 19:00:07 +0000	[diff] [blame]	1960	ret { i32, i8 } { i32 4, i8 2 } <i>; Return an aggregate of values 4 and 2</i>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1961	</pre>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1962	</div>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1963	<!-- _______________________________________________________________________ -->
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1964	<div class="doc_subsubsection"> <a name="i_br">'<tt>br</tt>' Instruction</a> </div>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1965	<div class="doc_text">
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1966	<h5>Syntax:</h5>
Reid Spencer	36a1542	2007-01-12 03:35:51 +0000	[diff] [blame]	1967	<pre> br i1 <cond>, label <iftrue>, label <iffalse><br> br label <dest> <i>; Unconditional branch</i>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1968	</pre>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1969	<h5>Overview:</h5>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1970	<p>The '<tt>br</tt>' instruction is used to cause control flow to
				1971	transfer to a different basic block in the current function. There are
				1972	two forms of this instruction, corresponding to a conditional branch
				1973	and an unconditional branch.</p>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1974	<h5>Arguments:</h5>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1975	<p>The conditional branch form of the '<tt>br</tt>' instruction takes a
Reid Spencer	36a1542	2007-01-12 03:35:51 +0000	[diff] [blame]	1976	single '<tt>i1</tt>' value and two '<tt>label</tt>' values. The
Reid Spencer	50c723a	2007-02-19 23:54:10 +0000	[diff] [blame]	1977	unconditional form of the '<tt>br</tt>' instruction takes a single
				1978	'<tt>label</tt>' value as a target.</p>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1979	<h5>Semantics:</h5>
Reid Spencer	36a1542	2007-01-12 03:35:51 +0000	[diff] [blame]	1980	<p>Upon execution of a conditional '<tt>br</tt>' instruction, the '<tt>i1</tt>'
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	1981	argument is evaluated. If the value is <tt>true</tt>, control flows
				1982	to the '<tt>iftrue</tt>' <tt>label</tt> argument. If "cond" is <tt>false</tt>,
				1983	control flows to the '<tt>iffalse</tt>' <tt>label</tt> argument.</p>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1984	<h5>Example:</h5>
Reid Spencer	36a1542	2007-01-12 03:35:51 +0000	[diff] [blame]	1985	<pre>Test:<br> %cond = <a href="#i_icmp">icmp</a> eq, i32 %a, %b<br> br i1 %cond, label %IfEqual, label %IfUnequal<br>IfEqual:<br> <a
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	1986	href="#i_ret">ret</a> i32 1<br>IfUnequal:<br> <a href="#i_ret">ret</a> i32 0<br></pre>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1987	</div>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1988	<!-- _______________________________________________________________________ -->
Chris Lattner	cf96c6c	2004-02-24 04:54:45 +0000	[diff] [blame]	1989	<div class="doc_subsubsection">
				1990	<a name="i_switch">'<tt>switch</tt>' Instruction</a>
				1991	</div>
				1992
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	1993	<div class="doc_text">
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	1994	<h5>Syntax:</h5>
Chris Lattner	cf96c6c	2004-02-24 04:54:45 +0000	[diff] [blame]	1995
				1996	<pre>
				1997	switch <intty> <value>, label <defaultdest> [ <intty> <val>, label <dest> ... ]
				1998	</pre>
				1999
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2000	<h5>Overview:</h5>
Chris Lattner	cf96c6c	2004-02-24 04:54:45 +0000	[diff] [blame]	2001
				2002	<p>The '<tt>switch</tt>' instruction is used to transfer control flow to one of
				2003	several different places. It is a generalization of the '<tt>br</tt>'
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2004	instruction, allowing a branch to occur to one of many possible
				2005	destinations.</p>
Chris Lattner	cf96c6c	2004-02-24 04:54:45 +0000	[diff] [blame]	2006
				2007
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2008	<h5>Arguments:</h5>
Chris Lattner	cf96c6c	2004-02-24 04:54:45 +0000	[diff] [blame]	2009
				2010	<p>The '<tt>switch</tt>' instruction uses three parameters: an integer
				2011	comparison value '<tt>value</tt>', a default '<tt>label</tt>' destination, and
				2012	an array of pairs of comparison value constants and '<tt>label</tt>'s. The
				2013	table is not allowed to contain duplicate constant entries.</p>
				2014
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2015	<h5>Semantics:</h5>
Chris Lattner	cf96c6c	2004-02-24 04:54:45 +0000	[diff] [blame]	2016
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2017	<p>The <tt>switch</tt> instruction specifies a table of values and
				2018	destinations. When the '<tt>switch</tt>' instruction is executed, this
John Criswell	bcbb18c	2004-06-25 16:05:06 +0000	[diff] [blame]	2019	table is searched for the given value. If the value is found, control flow is
				2020	transfered to the corresponding destination; otherwise, control flow is
				2021	transfered to the default destination.</p>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2022
Chris Lattner	cf96c6c	2004-02-24 04:54:45 +0000	[diff] [blame]	2023	<h5>Implementation:</h5>
				2024
				2025	<p>Depending on properties of the target machine and the particular
				2026	<tt>switch</tt> instruction, this instruction may be code generated in different
John Criswell	bcbb18c	2004-06-25 16:05:06 +0000	[diff] [blame]	2027	ways. For example, it could be generated as a series of chained conditional
				2028	branches or with a lookup table.</p>
Chris Lattner	cf96c6c	2004-02-24 04:54:45 +0000	[diff] [blame]	2029
				2030	<h5>Example:</h5>
				2031
				2032	<pre>
				2033	<i>; Emulate a conditional br instruction</i>
Reid Spencer	36a1542	2007-01-12 03:35:51 +0000	[diff] [blame]	2034	%Val = <a href="#i_zext">zext</a> i1 %value to i32
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	2035	switch i32 %Val, label %truedest [i32 0, label %falsedest ]
Chris Lattner	cf96c6c	2004-02-24 04:54:45 +0000	[diff] [blame]	2036
				2037	<i>; Emulate an unconditional br instruction</i>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	2038	switch i32 0, label %dest [ ]
Chris Lattner	cf96c6c	2004-02-24 04:54:45 +0000	[diff] [blame]	2039
				2040	<i>; Implement a jump table:</i>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	2041	switch i32 %val, label %otherwise [ i32 0, label %onzero
				2042	i32 1, label %onone
				2043	i32 2, label %ontwo ]
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2044	</pre>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2045	</div>
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	2046
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2047	<!-- _______________________________________________________________________ -->
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	2048	<div class="doc_subsubsection">
				2049	<a name="i_invoke">'<tt>invoke</tt>' Instruction</a>
				2050	</div>
				2051
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2052	<div class="doc_text">
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	2053
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2054	<h5>Syntax:</h5>
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	2055
				2056	<pre>
Devang Patel	0225623	2008-10-07 17:48:33 +0000	[diff] [blame]	2057	<result> = invoke [<a href="#callingconv">cconv</a>] [<a href="#paramattrs">ret attrs</a>] <ptr to function ty> <function ptr val>(<function args>) [<a href="#fnattrs">fn attrs</a>]
Chris Lattner	6b7a008	2006-05-14 18:23:06 +0000	[diff] [blame]	2058	to label <normal label> unwind label <exception label>
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	2059	</pre>
				2060
Chris Lattner	a8292f3	2002-05-06 22:08:29 +0000	[diff] [blame]	2061	<h5>Overview:</h5>
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	2062
				2063	<p>The '<tt>invoke</tt>' instruction causes control to transfer to a specified
				2064	function, with the possibility of control flow transfer to either the
John Criswell	02fdc6f	2005-05-12 16:52:32 +0000	[diff] [blame]	2065	'<tt>normal</tt>' label or the
				2066	'<tt>exception</tt>' label. If the callee function returns with the
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	2067	"<tt><a href="#i_ret">ret</a></tt>" instruction, control flow will return to the
				2068	"normal" label. If the callee (or any indirect callees) returns with the "<a
John Criswell	02fdc6f	2005-05-12 16:52:32 +0000	[diff] [blame]	2069	href="#i_unwind"><tt>unwind</tt></a>" instruction, control is interrupted and
Dan Gohman	cc3132e	2008-10-04 19:00:07 +0000	[diff] [blame]	2070	continued at the dynamically nearest "exception" label.
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	2071
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2072	<h5>Arguments:</h5>
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	2073
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2074	<p>This instruction requires several arguments:</p>
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	2075
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2076	<ol>
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	2077	<li>
Duncan Sands	16f122e	2007-03-30 12:22:09 +0000	[diff] [blame]	2078	The optional "cconv" marker indicates which <a href="#callingconv">calling
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	2079	convention</a> the call should use. If none is specified, the call defaults
				2080	to using C calling conventions.
				2081	</li>
Devang Patel	7e9b05e	2008-10-06 18:50:38 +0000	[diff] [blame]	2082
				2083	<li>The optional <a href="#paramattrs">Parameter Attributes</a> list for
				2084	return values. Only '<tt>zeroext</tt>', '<tt>signext</tt>',
				2085	and '<tt>inreg</tt>' attributes are valid here.</li>
				2086
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	2087	<li>'<tt>ptr to function ty</tt>': shall be the signature of the pointer to
				2088	function value being invoked. In most cases, this is a direct function
				2089	invocation, but indirect <tt>invoke</tt>s are just as possible, branching off
				2090	an arbitrary pointer to function value.
				2091	</li>
				2092
				2093	<li>'<tt>function ptr val</tt>': An LLVM value containing a pointer to a
				2094	function to be invoked. </li>
				2095
				2096	<li>'<tt>function args</tt>': argument list whose types match the function
				2097	signature argument types. If the function signature indicates the function
				2098	accepts a variable number of arguments, the extra arguments can be
				2099	specified. </li>
				2100
				2101	<li>'<tt>normal label</tt>': the label reached when the called function
				2102	executes a '<tt><a href="#i_ret">ret</a></tt>' instruction. </li>
				2103
				2104	<li>'<tt>exception label</tt>': the label reached when a callee returns with
				2105	the <a href="#i_unwind"><tt>unwind</tt></a> instruction. </li>
				2106
Devang Patel	0225623	2008-10-07 17:48:33 +0000	[diff] [blame]	2107	<li>The optional <a href="#fnattrs">function attributes</a> list. Only
Devang Patel	7e9b05e	2008-10-06 18:50:38 +0000	[diff] [blame]	2108	'<tt>noreturn</tt>', '<tt>nounwind</tt>', '<tt>readonly</tt>' and
				2109	'<tt>readnone</tt>' attributes are valid here.</li>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2110	</ol>
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	2111
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2112	<h5>Semantics:</h5>
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	2113
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2114	<p>This instruction is designed to operate as a standard '<tt><a
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	2115	href="#i_call">call</a></tt>' instruction in most regards. The primary
				2116	difference is that it establishes an association with a label, which is used by
				2117	the runtime library to unwind the stack.</p>
				2118
				2119	<p>This instruction is used in languages with destructors to ensure that proper
				2120	cleanup is performed in the case of either a <tt>longjmp</tt> or a thrown
				2121	exception. Additionally, this is important for implementation of
				2122	'<tt>catch</tt>' clauses in high-level languages that support them.</p>
				2123
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2124	<h5>Example:</h5>
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	2125	<pre>
Nick Lewycky	084ab47	2008-03-16 07:18:12 +0000	[diff] [blame]	2126	%retval = invoke i32 @Test(i32 15) to label %Continue
Jeff Cohen	5819f18	2007-04-22 01:17:39 +0000	[diff] [blame]	2127	unwind label %TestCleanup <i>; {i32}:retval set</i>
Nick Lewycky	084ab47	2008-03-16 07:18:12 +0000	[diff] [blame]	2128	%retval = invoke <a href="#callingconv">coldcc</a> i32 %Testfnptr(i32 15) to label %Continue
Jeff Cohen	5819f18	2007-04-22 01:17:39 +0000	[diff] [blame]	2129	unwind label %TestCleanup <i>; {i32}:retval set</i>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2130	</pre>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2131	</div>
Chris Lattner	08b7d5b	2004-10-16 18:04:13 +0000	[diff] [blame]	2132
				2133
Chris Lattner	5ed6061	2003-09-03 00:41:47 +0000	[diff] [blame]	2134	<!-- _______________________________________________________________________ -->
Chris Lattner	08b7d5b	2004-10-16 18:04:13 +0000	[diff] [blame]	2135
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2136	<div class="doc_subsubsection"> <a name="i_unwind">'<tt>unwind</tt>'
				2137	Instruction</a> </div>
Chris Lattner	08b7d5b	2004-10-16 18:04:13 +0000	[diff] [blame]	2138
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2139	<div class="doc_text">
Chris Lattner	08b7d5b	2004-10-16 18:04:13 +0000	[diff] [blame]	2140
Chris Lattner	5ed6061	2003-09-03 00:41:47 +0000	[diff] [blame]	2141	<h5>Syntax:</h5>
Chris Lattner	08b7d5b	2004-10-16 18:04:13 +0000	[diff] [blame]	2142	<pre>
				2143	unwind
				2144	</pre>
				2145
Chris Lattner	5ed6061	2003-09-03 00:41:47 +0000	[diff] [blame]	2146	<h5>Overview:</h5>
Chris Lattner	08b7d5b	2004-10-16 18:04:13 +0000	[diff] [blame]	2147
				2148	<p>The '<tt>unwind</tt>' instruction unwinds the stack, continuing control flow
				2149	at the first callee in the dynamic call stack which used an <a
				2150	href="#i_invoke"><tt>invoke</tt></a> instruction to perform the call. This is
				2151	primarily used to implement exception handling.</p>
				2152
Chris Lattner	5ed6061	2003-09-03 00:41:47 +0000	[diff] [blame]	2153	<h5>Semantics:</h5>
Chris Lattner	08b7d5b	2004-10-16 18:04:13 +0000	[diff] [blame]	2154
Chris Lattner	fe8519c	2008-04-19 21:01:16 +0000	[diff] [blame]	2155	<p>The '<tt>unwind</tt>' instruction causes execution of the current function to
Chris Lattner	08b7d5b	2004-10-16 18:04:13 +0000	[diff] [blame]	2156	immediately halt. The dynamic call stack is then searched for the first <a
				2157	href="#i_invoke"><tt>invoke</tt></a> instruction on the call stack. Once found,
				2158	execution continues at the "exceptional" destination block specified by the
				2159	<tt>invoke</tt> instruction. If there is no <tt>invoke</tt> instruction in the
				2160	dynamic call chain, undefined behavior results.</p>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2161	</div>
Chris Lattner	08b7d5b	2004-10-16 18:04:13 +0000	[diff] [blame]	2162
				2163	<!-- _______________________________________________________________________ -->
				2164
				2165	<div class="doc_subsubsection"> <a name="i_unreachable">'<tt>unreachable</tt>'
				2166	Instruction</a> </div>
				2167
				2168	<div class="doc_text">
				2169
				2170	<h5>Syntax:</h5>
				2171	<pre>
				2172	unreachable
				2173	</pre>
				2174
				2175	<h5>Overview:</h5>
				2176
				2177	<p>The '<tt>unreachable</tt>' instruction has no defined semantics. This
				2178	instruction is used to inform the optimizer that a particular portion of the
				2179	code is not reachable. This can be used to indicate that the code after a
				2180	no-return function cannot be reached, and other facts.</p>
				2181
				2182	<h5>Semantics:</h5>
				2183
				2184	<p>The '<tt>unreachable</tt>' instruction has no defined semantics.</p>
				2185	</div>
				2186
				2187
				2188
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2189	<!-- ======================================================================= -->
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2190	<div class="doc_subsection"> <a name="binaryops">Binary Operations</a> </div>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2191	<div class="doc_text">
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2192	<p>Binary operators are used to do most of the computation in a
Chris Lattner	81f9297	2008-04-01 18:47:32 +0000	[diff] [blame]	2193	program. They require two operands of the same type, execute an operation on them, and
John Criswell	dfe6a86	2004-12-10 15:51:16 +0000	[diff] [blame]	2194	produce a single value. The operands might represent
Reid Spencer	404a325	2007-02-15 03:07:05 +0000	[diff] [blame]	2195	multiple data, as is the case with the <a href="#t_vector">vector</a> data type.
Chris Lattner	81f9297	2008-04-01 18:47:32 +0000	[diff] [blame]	2196	The result value has the same type as its operands.</p>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2197	<p>There are several different binary operators:</p>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2198	</div>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2199	<!-- _______________________________________________________________________ -->
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2200	<div class="doc_subsubsection">
				2201	<a name="i_add">'<tt>add</tt>' Instruction</a>
				2202	</div>
				2203
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2204	<div class="doc_text">
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2205
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2206	<h5>Syntax:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2207
				2208	<pre>
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2209	<result> = add <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2210	</pre>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2211
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2212	<h5>Overview:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2213
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2214	<p>The '<tt>add</tt>' instruction returns the sum of its two operands.</p>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2215
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2216	<h5>Arguments:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2217
				2218	<p>The two arguments to the '<tt>add</tt>' instruction must be <a
				2219	href="#t_integer">integer</a>, <a href="#t_floating">floating point</a>, or
				2220	<a href="#t_vector">vector</a> values. Both arguments must have identical
				2221	types.</p>
				2222
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2223	<h5>Semantics:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2224
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2225	<p>The value produced is the integer or floating point sum of the two
				2226	operands.</p>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2227
Chris Lattner	2f2427e	2008-01-28 00:36:27 +0000	[diff] [blame]	2228	<p>If an integer sum has unsigned overflow, the result returned is the
				2229	mathematical result modulo 2<sup>n</sup>, where n is the bit width of
				2230	the result.</p>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2231
Chris Lattner	2f2427e	2008-01-28 00:36:27 +0000	[diff] [blame]	2232	<p>Because LLVM integers use a two's complement representation, this
				2233	instruction is appropriate for both signed and unsigned integers.</p>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2234
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2235	<h5>Example:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2236
				2237	<pre>
				2238	<result> = add i32 4, %var <i>; yields {i32}:result = 4 + %var</i>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2239	</pre>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2240	</div>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2241	<!-- _______________________________________________________________________ -->
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2242	<div class="doc_subsubsection">
				2243	<a name="i_sub">'<tt>sub</tt>' Instruction</a>
				2244	</div>
				2245
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2246	<div class="doc_text">
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2247
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2248	<h5>Syntax:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2249
				2250	<pre>
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2251	<result> = sub <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2252	</pre>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2253
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2254	<h5>Overview:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2255
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2256	<p>The '<tt>sub</tt>' instruction returns the difference of its two
				2257	operands.</p>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2258
				2259	<p>Note that the '<tt>sub</tt>' instruction is used to represent the
				2260	'<tt>neg</tt>' instruction present in most other intermediate
				2261	representations.</p>
				2262
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2263	<h5>Arguments:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2264
				2265	<p>The two arguments to the '<tt>sub</tt>' instruction must be <a
				2266	href="#t_integer">integer</a>, <a href="#t_floating">floating point</a>,
				2267	or <a href="#t_vector">vector</a> values. Both arguments must have identical
				2268	types.</p>
				2269
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2270	<h5>Semantics:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2271
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2272	<p>The value produced is the integer or floating point difference of
				2273	the two operands.</p>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2274
Chris Lattner	2f2427e	2008-01-28 00:36:27 +0000	[diff] [blame]	2275	<p>If an integer difference has unsigned overflow, the result returned is the
				2276	mathematical result modulo 2<sup>n</sup>, where n is the bit width of
				2277	the result.</p>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2278
Chris Lattner	2f2427e	2008-01-28 00:36:27 +0000	[diff] [blame]	2279	<p>Because LLVM integers use a two's complement representation, this
				2280	instruction is appropriate for both signed and unsigned integers.</p>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2281
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2282	<h5>Example:</h5>
Bill Wendling	2d8b9a8	2007-05-29 09:42:13 +0000	[diff] [blame]	2283	<pre>
				2284	<result> = sub i32 4, %var <i>; yields {i32}:result = 4 - %var</i>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	2285	<result> = sub i32 0, %val <i>; yields {i32}:result = -%var</i>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2286	</pre>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2287	</div>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2288
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2289	<!-- _______________________________________________________________________ -->
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2290	<div class="doc_subsubsection">
				2291	<a name="i_mul">'<tt>mul</tt>' Instruction</a>
				2292	</div>
				2293
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2294	<div class="doc_text">
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2295
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2296	<h5>Syntax:</h5>
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2297	<pre> <result> = mul <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2298	</pre>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2299	<h5>Overview:</h5>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2300	<p>The '<tt>mul</tt>' instruction returns the product of its two
				2301	operands.</p>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2302
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2303	<h5>Arguments:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2304
				2305	<p>The two arguments to the '<tt>mul</tt>' instruction must be <a
				2306	href="#t_integer">integer</a>, <a href="#t_floating">floating point</a>,
				2307	or <a href="#t_vector">vector</a> values. Both arguments must have identical
				2308	types.</p>
				2309
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2310	<h5>Semantics:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2311
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2312	<p>The value produced is the integer or floating point product of the
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2313	two operands.</p>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2314
Chris Lattner	2f2427e	2008-01-28 00:36:27 +0000	[diff] [blame]	2315	<p>If the result of an integer multiplication has unsigned overflow,
				2316	the result returned is the mathematical result modulo
				2317	2<sup>n</sup>, where n is the bit width of the result.</p>
				2318	<p>Because LLVM integers use a two's complement representation, and the
				2319	result is the same width as the operands, this instruction returns the
				2320	correct result for both signed and unsigned integers. If a full product
				2321	(e.g. <tt>i32</tt>x<tt>i32</tt>-><tt>i64</tt>) is needed, the operands
				2322	should be sign-extended or zero-extended as appropriate to the
				2323	width of the full product.</p>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2324	<h5>Example:</h5>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	2325	<pre> <result> = mul i32 4, %var <i>; yields {i32}:result = 4 * %var</i>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2326	</pre>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2327	</div>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2328
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2329	<!-- _______________________________________________________________________ -->
Reid Spencer	7e80b0b	2006-10-26 06:15:43 +0000	[diff] [blame]	2330	<div class="doc_subsubsection"> <a name="i_udiv">'<tt>udiv</tt>' Instruction
				2331	</a></div>
				2332	<div class="doc_text">
				2333	<h5>Syntax:</h5>
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2334	<pre> <result> = udiv <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Reid Spencer	7e80b0b	2006-10-26 06:15:43 +0000	[diff] [blame]	2335	</pre>
				2336	<h5>Overview:</h5>
				2337	<p>The '<tt>udiv</tt>' instruction returns the quotient of its two
				2338	operands.</p>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2339
Reid Spencer	7e80b0b	2006-10-26 06:15:43 +0000	[diff] [blame]	2340	<h5>Arguments:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2341
Reid Spencer	7e80b0b	2006-10-26 06:15:43 +0000	[diff] [blame]	2342	<p>The two arguments to the '<tt>udiv</tt>' instruction must be
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2343	<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
				2344	values. Both arguments must have identical types.</p>
				2345
Reid Spencer	7e80b0b	2006-10-26 06:15:43 +0000	[diff] [blame]	2346	<h5>Semantics:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2347
Chris Lattner	2f2427e	2008-01-28 00:36:27 +0000	[diff] [blame]	2348	<p>The value produced is the unsigned integer quotient of the two operands.</p>
				2349	<p>Note that unsigned integer division and signed integer division are distinct
				2350	operations; for signed integer division, use '<tt>sdiv</tt>'.</p>
				2351	<p>Division by zero leads to undefined behavior.</p>
Reid Spencer	7e80b0b	2006-10-26 06:15:43 +0000	[diff] [blame]	2352	<h5>Example:</h5>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	2353	<pre> <result> = udiv i32 4, %var <i>; yields {i32}:result = 4 / %var</i>
Reid Spencer	7e80b0b	2006-10-26 06:15:43 +0000	[diff] [blame]	2354	</pre>
				2355	</div>
				2356	<!-- _______________________________________________________________________ -->
				2357	<div class="doc_subsubsection"> <a name="i_sdiv">'<tt>sdiv</tt>' Instruction
				2358	</a> </div>
				2359	<div class="doc_text">
				2360	<h5>Syntax:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2361	<pre>
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2362	<result> = sdiv <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Reid Spencer	7e80b0b	2006-10-26 06:15:43 +0000	[diff] [blame]	2363	</pre>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2364
Reid Spencer	7e80b0b	2006-10-26 06:15:43 +0000	[diff] [blame]	2365	<h5>Overview:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2366
Reid Spencer	7e80b0b	2006-10-26 06:15:43 +0000	[diff] [blame]	2367	<p>The '<tt>sdiv</tt>' instruction returns the quotient of its two
				2368	operands.</p>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2369
Reid Spencer	7e80b0b	2006-10-26 06:15:43 +0000	[diff] [blame]	2370	<h5>Arguments:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2371
				2372	<p>The two arguments to the '<tt>sdiv</tt>' instruction must be
				2373	<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
				2374	values. Both arguments must have identical types.</p>
				2375
Reid Spencer	7e80b0b	2006-10-26 06:15:43 +0000	[diff] [blame]	2376	<h5>Semantics:</h5>
Chris Lattner	1429e6f	2008-04-01 18:45:27 +0000	[diff] [blame]	2377	<p>The value produced is the signed integer quotient of the two operands rounded towards zero.</p>
Chris Lattner	2f2427e	2008-01-28 00:36:27 +0000	[diff] [blame]	2378	<p>Note that signed integer division and unsigned integer division are distinct
				2379	operations; for unsigned integer division, use '<tt>udiv</tt>'.</p>
				2380	<p>Division by zero leads to undefined behavior. Overflow also leads to
				2381	undefined behavior; this is a rare case, but can occur, for example,
				2382	by doing a 32-bit division of -2147483648 by -1.</p>
Reid Spencer	7e80b0b	2006-10-26 06:15:43 +0000	[diff] [blame]	2383	<h5>Example:</h5>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	2384	<pre> <result> = sdiv i32 4, %var <i>; yields {i32}:result = 4 / %var</i>
Reid Spencer	7e80b0b	2006-10-26 06:15:43 +0000	[diff] [blame]	2385	</pre>
				2386	</div>
				2387	<!-- _______________________________________________________________________ -->
				2388	<div class="doc_subsubsection"> <a name="i_fdiv">'<tt>fdiv</tt>'
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2389	Instruction</a> </div>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2390	<div class="doc_text">
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2391	<h5>Syntax:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2392	<pre>
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2393	<result> = fdiv <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2394	</pre>
				2395	<h5>Overview:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2396
Reid Spencer	7e80b0b	2006-10-26 06:15:43 +0000	[diff] [blame]	2397	<p>The '<tt>fdiv</tt>' instruction returns the quotient of its two
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2398	operands.</p>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2399
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2400	<h5>Arguments:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2401
Jeff Cohen	5819f18	2007-04-22 01:17:39 +0000	[diff] [blame]	2402	<p>The two arguments to the '<tt>fdiv</tt>' instruction must be
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2403	<a href="#t_floating">floating point</a> or <a href="#t_vector">vector</a>
				2404	of floating point values. Both arguments must have identical types.</p>
				2405
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2406	<h5>Semantics:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2407
Reid Spencer	7e80b0b	2006-10-26 06:15:43 +0000	[diff] [blame]	2408	<p>The value produced is the floating point quotient of the two operands.</p>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2409
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2410	<h5>Example:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2411
				2412	<pre>
				2413	<result> = fdiv float 4.0, %var <i>; yields {float}:result = 4.0 / %var</i>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2414	</pre>
				2415	</div>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2416
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2417	<!-- _______________________________________________________________________ -->
Reid Spencer	7eb55b3	2006-11-02 01:53:59 +0000	[diff] [blame]	2418	<div class="doc_subsubsection"> <a name="i_urem">'<tt>urem</tt>' Instruction</a>
				2419	</div>
				2420	<div class="doc_text">
				2421	<h5>Syntax:</h5>
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2422	<pre> <result> = urem <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Reid Spencer	7eb55b3	2006-11-02 01:53:59 +0000	[diff] [blame]	2423	</pre>
				2424	<h5>Overview:</h5>
				2425	<p>The '<tt>urem</tt>' instruction returns the remainder from the
				2426	unsigned division of its two arguments.</p>
				2427	<h5>Arguments:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2428	<p>The two arguments to the '<tt>urem</tt>' instruction must be
				2429	<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
				2430	values. Both arguments must have identical types.</p>
Reid Spencer	7eb55b3	2006-11-02 01:53:59 +0000	[diff] [blame]	2431	<h5>Semantics:</h5>
				2432	<p>This instruction returns the unsigned integer <i>remainder</i> of a division.
Chris Lattner	1429e6f	2008-04-01 18:45:27 +0000	[diff] [blame]	2433	This instruction always performs an unsigned division to get the remainder.</p>
Chris Lattner	2f2427e	2008-01-28 00:36:27 +0000	[diff] [blame]	2434	<p>Note that unsigned integer remainder and signed integer remainder are
				2435	distinct operations; for signed integer remainder, use '<tt>srem</tt>'.</p>
				2436	<p>Taking the remainder of a division by zero leads to undefined behavior.</p>
Reid Spencer	7eb55b3	2006-11-02 01:53:59 +0000	[diff] [blame]	2437	<h5>Example:</h5>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	2438	<pre> <result> = urem i32 4, %var <i>; yields {i32}:result = 4 % %var</i>
Reid Spencer	7eb55b3	2006-11-02 01:53:59 +0000	[diff] [blame]	2439	</pre>
				2440
				2441	</div>
				2442	<!-- _______________________________________________________________________ -->
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2443	<div class="doc_subsubsection">
				2444	<a name="i_srem">'<tt>srem</tt>' Instruction</a>
				2445	</div>
				2446
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2447	<div class="doc_text">
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2448
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2449	<h5>Syntax:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2450
				2451	<pre>
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2452	<result> = srem <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2453	</pre>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2454
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2455	<h5>Overview:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2456
Reid Spencer	7eb55b3	2006-11-02 01:53:59 +0000	[diff] [blame]	2457	<p>The '<tt>srem</tt>' instruction returns the remainder from the
Dan Gohman	08143e3	2007-11-05 23:35:22 +0000	[diff] [blame]	2458	signed division of its two operands. This instruction can also take
				2459	<a href="#t_vector">vector</a> versions of the values in which case
				2460	the elements must be integers.</p>
Chris Lattner	b8f816e	2008-01-04 04:33:49 +0000	[diff] [blame]	2461
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2462	<h5>Arguments:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2463
Reid Spencer	7eb55b3	2006-11-02 01:53:59 +0000	[diff] [blame]	2464	<p>The two arguments to the '<tt>srem</tt>' instruction must be
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2465	<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
				2466	values. Both arguments must have identical types.</p>
				2467
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2468	<h5>Semantics:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2469
Reid Spencer	7eb55b3	2006-11-02 01:53:59 +0000	[diff] [blame]	2470	<p>This instruction returns the <i>remainder</i> of a division (where the result
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2471	has the same sign as the dividend, <tt>op1</tt>), not the <i>modulo</i>
				2472	operator (where the result has the same sign as the divisor, <tt>op2</tt>) of
Reid Spencer	806ad6a	2007-03-24 22:23:39 +0000	[diff] [blame]	2473	a value. For more information about the difference, see <a
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2474	href="http://mathforum.org/dr.math/problems/anne.4.28.99.html">The
Reid Spencer	806ad6a	2007-03-24 22:23:39 +0000	[diff] [blame]	2475	Math Forum</a>. For a table of how this is implemented in various languages,
Reid Spencer	db3b93b	2007-03-24 22:40:44 +0000	[diff] [blame]	2476	please see <a href="http://en.wikipedia.org/wiki/Modulo_operation">
Reid Spencer	806ad6a	2007-03-24 22:23:39 +0000	[diff] [blame]	2477	Wikipedia: modulo operation</a>.</p>
Chris Lattner	2f2427e	2008-01-28 00:36:27 +0000	[diff] [blame]	2478	<p>Note that signed integer remainder and unsigned integer remainder are
				2479	distinct operations; for unsigned integer remainder, use '<tt>urem</tt>'.</p>
				2480	<p>Taking the remainder of a division by zero leads to undefined behavior.
				2481	Overflow also leads to undefined behavior; this is a rare case, but can occur,
				2482	for example, by taking the remainder of a 32-bit division of -2147483648 by -1.
				2483	(The remainder doesn't actually overflow, but this rule lets srem be
				2484	implemented using instructions that return both the result of the division
				2485	and the remainder.)</p>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2486	<h5>Example:</h5>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	2487	<pre> <result> = srem i32 4, %var <i>; yields {i32}:result = 4 % %var</i>
Reid Spencer	7eb55b3	2006-11-02 01:53:59 +0000	[diff] [blame]	2488	</pre>
				2489
				2490	</div>
				2491	<!-- _______________________________________________________________________ -->
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2492	<div class="doc_subsubsection">
				2493	<a name="i_frem">'<tt>frem</tt>' Instruction</a> </div>
				2494
Reid Spencer	7eb55b3	2006-11-02 01:53:59 +0000	[diff] [blame]	2495	<div class="doc_text">
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2496
Reid Spencer	7eb55b3	2006-11-02 01:53:59 +0000	[diff] [blame]	2497	<h5>Syntax:</h5>
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2498	<pre> <result> = frem <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Reid Spencer	7eb55b3	2006-11-02 01:53:59 +0000	[diff] [blame]	2499	</pre>
				2500	<h5>Overview:</h5>
				2501	<p>The '<tt>frem</tt>' instruction returns the remainder from the
				2502	division of its two operands.</p>
				2503	<h5>Arguments:</h5>
				2504	<p>The two arguments to the '<tt>frem</tt>' instruction must be
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2505	<a href="#t_floating">floating point</a> or <a href="#t_vector">vector</a>
				2506	of floating point values. Both arguments must have identical types.</p>
				2507
Reid Spencer	7eb55b3	2006-11-02 01:53:59 +0000	[diff] [blame]	2508	<h5>Semantics:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2509
Chris Lattner	1429e6f	2008-04-01 18:45:27 +0000	[diff] [blame]	2510	<p>This instruction returns the <i>remainder</i> of a division.
				2511	The remainder has the same sign as the dividend.</p>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2512
Reid Spencer	7eb55b3	2006-11-02 01:53:59 +0000	[diff] [blame]	2513	<h5>Example:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2514
				2515	<pre>
				2516	<result> = frem float 4.0, %var <i>; yields {float}:result = 4.0 % %var</i>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2517	</pre>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2518	</div>
Robert Bocchino	820bc75b	2006-02-17 21:18:08 +0000	[diff] [blame]	2519
Reid Spencer	2ab0193	2007-02-02 13:57:07 +0000	[diff] [blame]	2520	<!-- ======================================================================= -->
				2521	<div class="doc_subsection"> <a name="bitwiseops">Bitwise Binary
				2522	Operations</a> </div>
				2523	<div class="doc_text">
				2524	<p>Bitwise binary operators are used to do various forms of
				2525	bit-twiddling in a program. They are generally very efficient
				2526	instructions and can commonly be strength reduced from other
Chris Lattner	1429e6f	2008-04-01 18:45:27 +0000	[diff] [blame]	2527	instructions. They require two operands of the same type, execute an operation on them,
				2528	and produce a single value. The resulting value is the same type as its operands.</p>
Reid Spencer	2ab0193	2007-02-02 13:57:07 +0000	[diff] [blame]	2529	</div>
				2530
Reid Spencer	04e259b	2007-01-31 21:39:12 +0000	[diff] [blame]	2531	<!-- _______________________________________________________________________ -->
				2532	<div class="doc_subsubsection"> <a name="i_shl">'<tt>shl</tt>'
				2533	Instruction</a> </div>
				2534	<div class="doc_text">
				2535	<h5>Syntax:</h5>
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2536	<pre> <result> = shl <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Reid Spencer	04e259b	2007-01-31 21:39:12 +0000	[diff] [blame]	2537	</pre>
Chris Lattner	f0e5011	2007-10-03 21:01:14 +0000	[diff] [blame]	2538
Reid Spencer	04e259b	2007-01-31 21:39:12 +0000	[diff] [blame]	2539	<h5>Overview:</h5>
Chris Lattner	f0e5011	2007-10-03 21:01:14 +0000	[diff] [blame]	2540
Reid Spencer	04e259b	2007-01-31 21:39:12 +0000	[diff] [blame]	2541	<p>The '<tt>shl</tt>' instruction returns the first operand shifted to
				2542	the left a specified number of bits.</p>
Chris Lattner	f0e5011	2007-10-03 21:01:14 +0000	[diff] [blame]	2543
Reid Spencer	04e259b	2007-01-31 21:39:12 +0000	[diff] [blame]	2544	<h5>Arguments:</h5>
Chris Lattner	f0e5011	2007-10-03 21:01:14 +0000	[diff] [blame]	2545
Reid Spencer	04e259b	2007-01-31 21:39:12 +0000	[diff] [blame]	2546	<p>Both arguments to the '<tt>shl</tt>' instruction must be the same <a
Nate Begeman	fecbc8c	2008-07-29 15:49:41 +0000	[diff] [blame]	2547	href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2548	type. '<tt>op2</tt>' is treated as an unsigned value.</p>
Chris Lattner	f0e5011	2007-10-03 21:01:14 +0000	[diff] [blame]	2549
Reid Spencer	04e259b	2007-01-31 21:39:12 +0000	[diff] [blame]	2550	<h5>Semantics:</h5>
Chris Lattner	f0e5011	2007-10-03 21:01:14 +0000	[diff] [blame]	2551
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2552	<p>The value produced is <tt>op1</tt> * 2<sup><tt>op2</tt></sup> mod 2<sup>n</sup>,
				2553	where n is the width of the result. If <tt>op2</tt> is (statically or dynamically) negative or
				2554	equal to or larger than the number of bits in <tt>op1</tt>, the result is undefined.</p>
Chris Lattner	f0e5011	2007-10-03 21:01:14 +0000	[diff] [blame]	2555
Reid Spencer	04e259b	2007-01-31 21:39:12 +0000	[diff] [blame]	2556	<h5>Example:</h5><pre>
				2557	<result> = shl i32 4, %var <i>; yields {i32}: 4 << %var</i>
				2558	<result> = shl i32 4, 2 <i>; yields {i32}: 16</i>
				2559	<result> = shl i32 1, 10 <i>; yields {i32}: 1024</i>
Chris Lattner	f0e5011	2007-10-03 21:01:14 +0000	[diff] [blame]	2560	<result> = shl i32 1, 32 <i>; undefined</i>
Reid Spencer	04e259b	2007-01-31 21:39:12 +0000	[diff] [blame]	2561	</pre>
				2562	</div>
				2563	<!-- _______________________________________________________________________ -->
				2564	<div class="doc_subsubsection"> <a name="i_lshr">'<tt>lshr</tt>'
				2565	Instruction</a> </div>
				2566	<div class="doc_text">
				2567	<h5>Syntax:</h5>
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2568	<pre> <result> = lshr <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Reid Spencer	04e259b	2007-01-31 21:39:12 +0000	[diff] [blame]	2569	</pre>
				2570
				2571	<h5>Overview:</h5>
				2572	<p>The '<tt>lshr</tt>' instruction (logical shift right) returns the first
Jeff Cohen	5819f18	2007-04-22 01:17:39 +0000	[diff] [blame]	2573	operand shifted to the right a specified number of bits with zero fill.</p>
Reid Spencer	04e259b	2007-01-31 21:39:12 +0000	[diff] [blame]	2574
				2575	<h5>Arguments:</h5>
				2576	<p>Both arguments to the '<tt>lshr</tt>' instruction must be the same
Nate Begeman	fecbc8c	2008-07-29 15:49:41 +0000	[diff] [blame]	2577	<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2578	type. '<tt>op2</tt>' is treated as an unsigned value.</p>
Reid Spencer	04e259b	2007-01-31 21:39:12 +0000	[diff] [blame]	2579
				2580	<h5>Semantics:</h5>
Chris Lattner	f0e5011	2007-10-03 21:01:14 +0000	[diff] [blame]	2581
Reid Spencer	04e259b	2007-01-31 21:39:12 +0000	[diff] [blame]	2582	<p>This instruction always performs a logical shift right operation. The most
				2583	significant bits of the result will be filled with zero bits after the
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2584	shift. If <tt>op2</tt> is (statically or dynamically) equal to or larger than
				2585	the number of bits in <tt>op1</tt>, the result is undefined.</p>
Reid Spencer	04e259b	2007-01-31 21:39:12 +0000	[diff] [blame]	2586
				2587	<h5>Example:</h5>
				2588	<pre>
				2589	<result> = lshr i32 4, 1 <i>; yields {i32}:result = 2</i>
				2590	<result> = lshr i32 4, 2 <i>; yields {i32}:result = 1</i>
				2591	<result> = lshr i8 4, 3 <i>; yields {i8}:result = 0</i>
				2592	<result> = lshr i8 -2, 1 <i>; yields {i8}:result = 0x7FFFFFFF </i>
Chris Lattner	f0e5011	2007-10-03 21:01:14 +0000	[diff] [blame]	2593	<result> = lshr i32 1, 32 <i>; undefined</i>
Reid Spencer	04e259b	2007-01-31 21:39:12 +0000	[diff] [blame]	2594	</pre>
				2595	</div>
				2596
Reid Spencer	2ab0193	2007-02-02 13:57:07 +0000	[diff] [blame]	2597	<!-- _______________________________________________________________________ -->
Reid Spencer	04e259b	2007-01-31 21:39:12 +0000	[diff] [blame]	2598	<div class="doc_subsubsection"> <a name="i_ashr">'<tt>ashr</tt>'
				2599	Instruction</a> </div>
				2600	<div class="doc_text">
				2601
				2602	<h5>Syntax:</h5>
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2603	<pre> <result> = ashr <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Reid Spencer	04e259b	2007-01-31 21:39:12 +0000	[diff] [blame]	2604	</pre>
				2605
				2606	<h5>Overview:</h5>
				2607	<p>The '<tt>ashr</tt>' instruction (arithmetic shift right) returns the first
Jeff Cohen	5819f18	2007-04-22 01:17:39 +0000	[diff] [blame]	2608	operand shifted to the right a specified number of bits with sign extension.</p>
Reid Spencer	04e259b	2007-01-31 21:39:12 +0000	[diff] [blame]	2609
				2610	<h5>Arguments:</h5>
				2611	<p>Both arguments to the '<tt>ashr</tt>' instruction must be the same
Nate Begeman	fecbc8c	2008-07-29 15:49:41 +0000	[diff] [blame]	2612	<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2613	type. '<tt>op2</tt>' is treated as an unsigned value.</p>
Reid Spencer	04e259b	2007-01-31 21:39:12 +0000	[diff] [blame]	2614
				2615	<h5>Semantics:</h5>
				2616	<p>This instruction always performs an arithmetic shift right operation,
				2617	The most significant bits of the result will be filled with the sign bit
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2618	of <tt>op1</tt>. If <tt>op2</tt> is (statically or dynamically) equal to or
				2619	larger than the number of bits in <tt>op1</tt>, the result is undefined.
Chris Lattner	f0e5011	2007-10-03 21:01:14 +0000	[diff] [blame]	2620	</p>
Reid Spencer	04e259b	2007-01-31 21:39:12 +0000	[diff] [blame]	2621
				2622	<h5>Example:</h5>
				2623	<pre>
				2624	<result> = ashr i32 4, 1 <i>; yields {i32}:result = 2</i>
				2625	<result> = ashr i32 4, 2 <i>; yields {i32}:result = 1</i>
				2626	<result> = ashr i8 4, 3 <i>; yields {i8}:result = 0</i>
				2627	<result> = ashr i8 -2, 1 <i>; yields {i8}:result = -1</i>
Chris Lattner	f0e5011	2007-10-03 21:01:14 +0000	[diff] [blame]	2628	<result> = ashr i32 1, 32 <i>; undefined</i>
Reid Spencer	04e259b	2007-01-31 21:39:12 +0000	[diff] [blame]	2629	</pre>
				2630	</div>
				2631
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2632	<!-- _______________________________________________________________________ -->
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2633	<div class="doc_subsubsection"> <a name="i_and">'<tt>and</tt>'
				2634	Instruction</a> </div>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2635
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2636	<div class="doc_text">
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2637
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2638	<h5>Syntax:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2639
				2640	<pre>
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2641	<result> = and <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2642	</pre>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2643
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2644	<h5>Overview:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2645
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2646	<p>The '<tt>and</tt>' instruction returns the bitwise logical and of
				2647	its two operands.</p>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2648
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2649	<h5>Arguments:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2650
				2651	<p>The two arguments to the '<tt>and</tt>' instruction must be
				2652	<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
				2653	values. Both arguments must have identical types.</p>
				2654
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2655	<h5>Semantics:</h5>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2656	<p>The truth table used for the '<tt>and</tt>' instruction is:</p>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2657	<p> </p>
Bill Wendling	5703c6e	2008-09-07 10:29:20 +0000	[diff] [blame]	2658	<div>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2659	<table border="1" cellspacing="0" cellpadding="4">
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2660	<tbody>
				2661	<tr>
				2662	<td>In0</td>
				2663	<td>In1</td>
				2664	<td>Out</td>
				2665	</tr>
				2666	<tr>
				2667	<td>0</td>
				2668	<td>0</td>
				2669	<td>0</td>
				2670	</tr>
				2671	<tr>
				2672	<td>0</td>
				2673	<td>1</td>
				2674	<td>0</td>
				2675	</tr>
				2676	<tr>
				2677	<td>1</td>
				2678	<td>0</td>
				2679	<td>0</td>
				2680	</tr>
				2681	<tr>
				2682	<td>1</td>
				2683	<td>1</td>
				2684	<td>1</td>
				2685	</tr>
				2686	</tbody>
				2687	</table>
Misha Brukman	c501f55	2004-03-01 17:47:27 +0000	[diff] [blame]	2688	</div>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2689	<h5>Example:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2690	<pre>
				2691	<result> = and i32 4, %var <i>; yields {i32}:result = 4 & %var</i>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	2692	<result> = and i32 15, 40 <i>; yields {i32}:result = 8</i>
				2693	<result> = and i32 4, 8 <i>; yields {i32}:result = 0</i>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2694	</pre>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2695	</div>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2696	<!-- _______________________________________________________________________ -->
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2697	<div class="doc_subsubsection"> <a name="i_or">'<tt>or</tt>' Instruction</a> </div>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2698	<div class="doc_text">
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2699	<h5>Syntax:</h5>
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2700	<pre> <result> = or <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2701	</pre>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2702	<h5>Overview:</h5>
				2703	<p>The '<tt>or</tt>' instruction returns the bitwise logical inclusive
				2704	or of its two operands.</p>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2705	<h5>Arguments:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2706
				2707	<p>The two arguments to the '<tt>or</tt>' instruction must be
				2708	<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
				2709	values. Both arguments must have identical types.</p>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2710	<h5>Semantics:</h5>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2711	<p>The truth table used for the '<tt>or</tt>' instruction is:</p>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2712	<p> </p>
Bill Wendling	5703c6e	2008-09-07 10:29:20 +0000	[diff] [blame]	2713	<div>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2714	<table border="1" cellspacing="0" cellpadding="4">
				2715	<tbody>
				2716	<tr>
				2717	<td>In0</td>
				2718	<td>In1</td>
				2719	<td>Out</td>
				2720	</tr>
				2721	<tr>
				2722	<td>0</td>
				2723	<td>0</td>
				2724	<td>0</td>
				2725	</tr>
				2726	<tr>
				2727	<td>0</td>
				2728	<td>1</td>
				2729	<td>1</td>
				2730	</tr>
				2731	<tr>
				2732	<td>1</td>
				2733	<td>0</td>
				2734	<td>1</td>
				2735	</tr>
				2736	<tr>
				2737	<td>1</td>
				2738	<td>1</td>
				2739	<td>1</td>
				2740	</tr>
				2741	</tbody>
				2742	</table>
Misha Brukman	c501f55	2004-03-01 17:47:27 +0000	[diff] [blame]	2743	</div>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2744	<h5>Example:</h5>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	2745	<pre> <result> = or i32 4, %var <i>; yields {i32}:result = 4 \| %var</i>
				2746	<result> = or i32 15, 40 <i>; yields {i32}:result = 47</i>
				2747	<result> = or i32 4, 8 <i>; yields {i32}:result = 12</i>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2748	</pre>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2749	</div>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2750	<!-- _______________________________________________________________________ -->
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2751	<div class="doc_subsubsection"> <a name="i_xor">'<tt>xor</tt>'
				2752	Instruction</a> </div>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2753	<div class="doc_text">
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2754	<h5>Syntax:</h5>
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	2755	<pre> <result> = xor <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2756	</pre>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2757	<h5>Overview:</h5>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2758	<p>The '<tt>xor</tt>' instruction returns the bitwise logical exclusive
				2759	or of its two operands. The <tt>xor</tt> is used to implement the
				2760	"one's complement" operation, which is the "~" operator in C.</p>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2761	<h5>Arguments:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2762	<p>The two arguments to the '<tt>xor</tt>' instruction must be
				2763	<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
				2764	values. Both arguments must have identical types.</p>
				2765
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2766	<h5>Semantics:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	2767
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2768	<p>The truth table used for the '<tt>xor</tt>' instruction is:</p>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2769	<p> </p>
Bill Wendling	5703c6e	2008-09-07 10:29:20 +0000	[diff] [blame]	2770	<div>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2771	<table border="1" cellspacing="0" cellpadding="4">
				2772	<tbody>
				2773	<tr>
				2774	<td>In0</td>
				2775	<td>In1</td>
				2776	<td>Out</td>
				2777	</tr>
				2778	<tr>
				2779	<td>0</td>
				2780	<td>0</td>
				2781	<td>0</td>
				2782	</tr>
				2783	<tr>
				2784	<td>0</td>
				2785	<td>1</td>
				2786	<td>1</td>
				2787	</tr>
				2788	<tr>
				2789	<td>1</td>
				2790	<td>0</td>
				2791	<td>1</td>
				2792	</tr>
				2793	<tr>
				2794	<td>1</td>
				2795	<td>1</td>
				2796	<td>0</td>
				2797	</tr>
				2798	</tbody>
				2799	</table>
Misha Brukman	c501f55	2004-03-01 17:47:27 +0000	[diff] [blame]	2800	</div>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	2801	<p> </p>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2802	<h5>Example:</h5>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	2803	<pre> <result> = xor i32 4, %var <i>; yields {i32}:result = 4 ^ %var</i>
				2804	<result> = xor i32 15, 40 <i>; yields {i32}:result = 39</i>
				2805	<result> = xor i32 4, 8 <i>; yields {i32}:result = 12</i>
				2806	<result> = xor i32 %V, -1 <i>; yields {i32}:result = ~%V</i>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2807	</pre>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	2808	</div>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	2809
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	2810	<!-- ======================================================================= -->
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	2811	<div class="doc_subsection">
Chris Lattner	ce83bff	2006-04-08 23:07:04 +0000	[diff] [blame]	2812	<a name="vectorops">Vector Operations</a>
				2813	</div>
				2814
				2815	<div class="doc_text">
				2816
				2817	<p>LLVM supports several instructions to represent vector operations in a
Jeff Cohen	5819f18	2007-04-22 01:17:39 +0000	[diff] [blame]	2818	target-independent manner. These instructions cover the element-access and
Chris Lattner	ce83bff	2006-04-08 23:07:04 +0000	[diff] [blame]	2819	vector-specific operations needed to process vectors effectively. While LLVM
				2820	does directly support these vector operations, many sophisticated algorithms
				2821	will want to use target-specific intrinsics to take full advantage of a specific
				2822	target.</p>
				2823
				2824	</div>
				2825
				2826	<!-- _______________________________________________________________________ -->
				2827	<div class="doc_subsubsection">
				2828	<a name="i_extractelement">'<tt>extractelement</tt>' Instruction</a>
				2829	</div>
				2830
				2831	<div class="doc_text">
				2832
				2833	<h5>Syntax:</h5>
				2834
				2835	<pre>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	2836	<result> = extractelement <n x <ty>> <val>, i32 <idx> <i>; yields <ty></i>
Chris Lattner	ce83bff	2006-04-08 23:07:04 +0000	[diff] [blame]	2837	</pre>
				2838
				2839	<h5>Overview:</h5>
				2840
				2841	<p>
				2842	The '<tt>extractelement</tt>' instruction extracts a single scalar
Reid Spencer	404a325	2007-02-15 03:07:05 +0000	[diff] [blame]	2843	element from a vector at a specified index.
Chris Lattner	ce83bff	2006-04-08 23:07:04 +0000	[diff] [blame]	2844	</p>
				2845
				2846
				2847	<h5>Arguments:</h5>
				2848
				2849	<p>
				2850	The first operand of an '<tt>extractelement</tt>' instruction is a
Reid Spencer	404a325	2007-02-15 03:07:05 +0000	[diff] [blame]	2851	value of <a href="#t_vector">vector</a> type. The second operand is
Chris Lattner	ce83bff	2006-04-08 23:07:04 +0000	[diff] [blame]	2852	an index indicating the position from which to extract the element.
				2853	The index may be a variable.</p>
				2854
				2855	<h5>Semantics:</h5>
				2856
				2857	<p>
				2858	The result is a scalar of the same type as the element type of
				2859	<tt>val</tt>. Its value is the value at position <tt>idx</tt> of
				2860	<tt>val</tt>. If <tt>idx</tt> exceeds the length of <tt>val</tt>, the
				2861	results are undefined.
				2862	</p>
				2863
				2864	<h5>Example:</h5>
				2865
				2866	<pre>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	2867	%result = extractelement <4 x i32> %vec, i32 0 <i>; yields i32</i>
Chris Lattner	ce83bff	2006-04-08 23:07:04 +0000	[diff] [blame]	2868	</pre>
				2869	</div>
				2870
				2871
				2872	<!-- _______________________________________________________________________ -->
				2873	<div class="doc_subsubsection">
				2874	<a name="i_insertelement">'<tt>insertelement</tt>' Instruction</a>
				2875	</div>
				2876
				2877	<div class="doc_text">
				2878
				2879	<h5>Syntax:</h5>
				2880
				2881	<pre>
Dan Gohman	43ba067	2008-05-12 23:38:42 +0000	[diff] [blame]	2882	<result> = insertelement <n x <ty>> <val>, <ty> <elt>, i32 <idx> <i>; yields <n x <ty>></i>
Chris Lattner	ce83bff	2006-04-08 23:07:04 +0000	[diff] [blame]	2883	</pre>
				2884
				2885	<h5>Overview:</h5>
				2886
				2887	<p>
				2888	The '<tt>insertelement</tt>' instruction inserts a scalar
Reid Spencer	404a325	2007-02-15 03:07:05 +0000	[diff] [blame]	2889	element into a vector at a specified index.
Chris Lattner	ce83bff	2006-04-08 23:07:04 +0000	[diff] [blame]	2890	</p>
				2891
				2892
				2893	<h5>Arguments:</h5>
				2894
				2895	<p>
				2896	The first operand of an '<tt>insertelement</tt>' instruction is a
Reid Spencer	404a325	2007-02-15 03:07:05 +0000	[diff] [blame]	2897	value of <a href="#t_vector">vector</a> type. The second operand is a
Chris Lattner	ce83bff	2006-04-08 23:07:04 +0000	[diff] [blame]	2898	scalar value whose type must equal the element type of the first
				2899	operand. The third operand is an index indicating the position at
				2900	which to insert the value. The index may be a variable.</p>
				2901
				2902	<h5>Semantics:</h5>
				2903
				2904	<p>
Reid Spencer	404a325	2007-02-15 03:07:05 +0000	[diff] [blame]	2905	The result is a vector of the same type as <tt>val</tt>. Its
Chris Lattner	ce83bff	2006-04-08 23:07:04 +0000	[diff] [blame]	2906	element values are those of <tt>val</tt> except at position
				2907	<tt>idx</tt>, where it gets the value <tt>elt</tt>. If <tt>idx</tt>
				2908	exceeds the length of <tt>val</tt>, the results are undefined.
				2909	</p>
				2910
				2911	<h5>Example:</h5>
				2912
				2913	<pre>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	2914	%result = insertelement <4 x i32> %vec, i32 1, i32 0 <i>; yields <4 x i32></i>
Chris Lattner	ce83bff	2006-04-08 23:07:04 +0000	[diff] [blame]	2915	</pre>
				2916	</div>
				2917
				2918	<!-- _______________________________________________________________________ -->
				2919	<div class="doc_subsubsection">
				2920	<a name="i_shufflevector">'<tt>shufflevector</tt>' Instruction</a>
				2921	</div>
				2922
				2923	<div class="doc_text">
				2924
				2925	<h5>Syntax:</h5>
				2926
				2927	<pre>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	2928	<result> = shufflevector <n x <ty>> <v1>, <n x <ty>> <v2>, <n x i32> <mask> <i>; yields <n x <ty>></i>
Chris Lattner	ce83bff	2006-04-08 23:07:04 +0000	[diff] [blame]	2929	</pre>
				2930
				2931	<h5>Overview:</h5>
				2932
				2933	<p>
				2934	The '<tt>shufflevector</tt>' instruction constructs a permutation of elements
				2935	from two input vectors, returning a vector of the same type.
				2936	</p>
				2937
				2938	<h5>Arguments:</h5>
				2939
				2940	<p>
				2941	The first two operands of a '<tt>shufflevector</tt>' instruction are vectors
				2942	with types that match each other and types that match the result of the
				2943	instruction. The third argument is a shuffle mask, which has the same number
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	2944	of elements as the other vector type, but whose element type is always 'i32'.
Chris Lattner	ce83bff	2006-04-08 23:07:04 +0000	[diff] [blame]	2945	</p>
				2946
				2947	<p>
				2948	The shuffle mask operand is required to be a constant vector with either
				2949	constant integer or undef values.
				2950	</p>
				2951
				2952	<h5>Semantics:</h5>
				2953
				2954	<p>
				2955	The elements of the two input vectors are numbered from left to right across
				2956	both of the vectors. The shuffle mask operand specifies, for each element of
				2957	the result vector, which element of the two input registers the result element
				2958	gets. The element selector may be undef (meaning "don't care") and the second
				2959	operand may be undef if performing a shuffle from only one vector.
				2960	</p>
				2961
				2962	<h5>Example:</h5>
				2963
				2964	<pre>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	2965	%result = shufflevector <4 x i32> %v1, <4 x i32> %v2,
Jeff Cohen	5819f18	2007-04-22 01:17:39 +0000	[diff] [blame]	2966	<4 x i32> <i32 0, i32 4, i32 1, i32 5> <i>; yields <4 x i32></i>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	2967	%result = shufflevector <4 x i32> %v1, <4 x i32> undef,
				2968	<4 x i32> <i32 0, i32 1, i32 2, i32 3> <i>; yields <4 x i32></i> - Identity shuffle.
Chris Lattner	ce83bff	2006-04-08 23:07:04 +0000	[diff] [blame]	2969	</pre>
				2970	</div>
				2971
Tanya Lattner	b138bbe	2006-04-14 19:24:33 +0000	[diff] [blame]	2972
Chris Lattner	ce83bff	2006-04-08 23:07:04 +0000	[diff] [blame]	2973	<!-- ======================================================================= -->
				2974	<div class="doc_subsection">
Dan Gohman	b9d6660	2008-05-12 23:51:09 +0000	[diff] [blame]	2975	<a name="aggregateops">Aggregate Operations</a>
				2976	</div>
				2977
				2978	<div class="doc_text">
				2979
				2980	<p>LLVM supports several instructions for working with aggregate values.
				2981	</p>
				2982
				2983	</div>
				2984
				2985	<!-- _______________________________________________________________________ -->
				2986	<div class="doc_subsubsection">
				2987	<a name="i_extractvalue">'<tt>extractvalue</tt>' Instruction</a>
				2988	</div>
				2989
				2990	<div class="doc_text">
				2991
				2992	<h5>Syntax:</h5>
				2993
				2994	<pre>
				2995	<result> = extractvalue <aggregate type> <val>, <idx>{, <idx>}*
				2996	</pre>
				2997
				2998	<h5>Overview:</h5>
				2999
				3000	<p>
Dan Gohman	35a835c	2008-05-13 18:16:06 +0000	[diff] [blame]	3001	The '<tt>extractvalue</tt>' instruction extracts the value of a struct field
				3002	or array element from an aggregate value.
Dan Gohman	b9d6660	2008-05-12 23:51:09 +0000	[diff] [blame]	3003	</p>
				3004
				3005
				3006	<h5>Arguments:</h5>
				3007
				3008	<p>
				3009	The first operand of an '<tt>extractvalue</tt>' instruction is a
				3010	value of <a href="#t_struct">struct</a> or <a href="#t_array">array</a>
Dan Gohman	35a835c	2008-05-13 18:16:06 +0000	[diff] [blame]	3011	type. The operands are constant indices to specify which value to extract
Dan Gohman	1ecaf45	2008-05-31 00:58:22 +0000	[diff] [blame]	3012	in a similar manner as indices in a
Dan Gohman	b9d6660	2008-05-12 23:51:09 +0000	[diff] [blame]	3013	'<tt><a href="#i_getelementptr">getelementptr</a></tt>' instruction.
				3014	</p>
				3015
				3016	<h5>Semantics:</h5>
				3017
				3018	<p>
				3019	The result is the value at the position in the aggregate specified by
				3020	the index operands.
				3021	</p>
				3022
				3023	<h5>Example:</h5>
				3024
				3025	<pre>
Dan Gohman	1ecaf45	2008-05-31 00:58:22 +0000	[diff] [blame]	3026	%result = extractvalue {i32, float} %agg, 0 <i>; yields i32</i>
Dan Gohman	b9d6660	2008-05-12 23:51:09 +0000	[diff] [blame]	3027	</pre>
				3028	</div>
				3029
				3030
				3031	<!-- _______________________________________________________________________ -->
				3032	<div class="doc_subsubsection">
				3033	<a name="i_insertvalue">'<tt>insertvalue</tt>' Instruction</a>
				3034	</div>
				3035
				3036	<div class="doc_text">
				3037
				3038	<h5>Syntax:</h5>
				3039
				3040	<pre>
Dan Gohman	1ecaf45	2008-05-31 00:58:22 +0000	[diff] [blame]	3041	<result> = insertvalue <aggregate type> <val>, <ty> <val>, <idx> <i>; yields <n x <ty>></i>
Dan Gohman	b9d6660	2008-05-12 23:51:09 +0000	[diff] [blame]	3042	</pre>
				3043
				3044	<h5>Overview:</h5>
				3045
				3046	<p>
				3047	The '<tt>insertvalue</tt>' instruction inserts a value
Dan Gohman	35a835c	2008-05-13 18:16:06 +0000	[diff] [blame]	3048	into a struct field or array element in an aggregate.
Dan Gohman	b9d6660	2008-05-12 23:51:09 +0000	[diff] [blame]	3049	</p>
				3050
				3051
				3052	<h5>Arguments:</h5>
				3053
				3054	<p>
				3055	The first operand of an '<tt>insertvalue</tt>' instruction is a
				3056	value of <a href="#t_struct">struct</a> or <a href="#t_array">array</a> type.
				3057	The second operand is a first-class value to insert.
Dan Gohman	34d1c0d	2008-05-23 21:53:15 +0000	[diff] [blame]	3058	The following operands are constant indices
Dan Gohman	1ecaf45	2008-05-31 00:58:22 +0000	[diff] [blame]	3059	indicating the position at which to insert the value in a similar manner as
Dan Gohman	35a835c	2008-05-13 18:16:06 +0000	[diff] [blame]	3060	indices in a
Dan Gohman	b9d6660	2008-05-12 23:51:09 +0000	[diff] [blame]	3061	'<tt><a href="#i_getelementptr">getelementptr</a></tt>' instruction.
				3062	The value to insert must have the same type as the value identified
Dan Gohman	35a835c	2008-05-13 18:16:06 +0000	[diff] [blame]	3063	by the indices.
Dan Gohman	b9d6660	2008-05-12 23:51:09 +0000	[diff] [blame]	3064
				3065	<h5>Semantics:</h5>
				3066
				3067	<p>
				3068	The result is an aggregate of the same type as <tt>val</tt>. Its
				3069	value is that of <tt>val</tt> except that the value at the position
Dan Gohman	35a835c	2008-05-13 18:16:06 +0000	[diff] [blame]	3070	specified by the indices is that of <tt>elt</tt>.
Dan Gohman	b9d6660	2008-05-12 23:51:09 +0000	[diff] [blame]	3071	</p>
				3072
				3073	<h5>Example:</h5>
				3074
				3075	<pre>
Dan Gohman	88ce1a5	2008-06-23 15:26:37 +0000	[diff] [blame]	3076	%result = insertvalue {i32, float} %agg, i32 1, 0 <i>; yields {i32, float}</i>
Dan Gohman	b9d6660	2008-05-12 23:51:09 +0000	[diff] [blame]	3077	</pre>
				3078	</div>
				3079
				3080
				3081	<!-- ======================================================================= -->
				3082	<div class="doc_subsection">
Chris Lattner	6ab6672	2006-08-15 00:45:58 +0000	[diff] [blame]	3083	<a name="memoryops">Memory Access and Addressing Operations</a>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3084	</div>
				3085
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3086	<div class="doc_text">
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3087
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	3088	<p>A key design point of an SSA-based representation is how it
				3089	represents memory. In LLVM, no memory locations are in SSA form, which
				3090	makes things very simple. This section describes how to read, write,
John Criswell	dfe6a86	2004-12-10 15:51:16 +0000	[diff] [blame]	3091	allocate, and free memory in LLVM.</p>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3092
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3093	</div>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3094
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3095	<!-- _______________________________________________________________________ -->
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3096	<div class="doc_subsubsection">
				3097	<a name="i_malloc">'<tt>malloc</tt>' Instruction</a>
				3098	</div>
				3099
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3100	<div class="doc_text">
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3101
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3102	<h5>Syntax:</h5>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3103
				3104	<pre>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3105	<result> = malloc <type>[, i32 <NumElements>][, align <alignment>] <i>; yields {type*}:result</i>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3106	</pre>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3107
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3108	<h5>Overview:</h5>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3109
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	3110	<p>The '<tt>malloc</tt>' instruction allocates memory from the system
Christopher Lamb	55c6d4f	2007-12-17 01:00:21 +0000	[diff] [blame]	3111	heap and returns a pointer to it. The object is always allocated in the generic
				3112	address space (address space zero).</p>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3113
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3114	<h5>Arguments:</h5>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3115
				3116	<p>The '<tt>malloc</tt>' instruction allocates
				3117	<tt>sizeof(<type>)*NumElements</tt>
John Criswell	a92e586	2004-02-24 16:13:56 +0000	[diff] [blame]	3118	bytes of memory from the operating system and returns a pointer of the
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3119	appropriate type to the program. If "NumElements" is specified, it is the
Gabor Greif	dd1fc98	2008-02-09 22:24:34 +0000	[diff] [blame]	3120	number of elements allocated, otherwise "NumElements" is defaulted to be one.
Chris Lattner	1f17cce	2008-04-02 00:38:26 +0000	[diff] [blame]	3121	If a constant alignment is specified, the value result of the allocation is guaranteed to
Gabor Greif	dd1fc98	2008-02-09 22:24:34 +0000	[diff] [blame]	3122	be aligned to at least that boundary. If not specified, or if zero, the target can
				3123	choose to align the allocation on any convenient boundary.</p>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3124
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3125	<p>'<tt>type</tt>' must be a sized type.</p>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3126
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3127	<h5>Semantics:</h5>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3128
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	3129	<p>Memory is allocated using the system "<tt>malloc</tt>" function, and
Chris Lattner	fe8519c	2008-04-19 21:01:16 +0000	[diff] [blame]	3130	a pointer is returned. The result of a zero byte allocattion is undefined. The
				3131	result is null if there is insufficient memory available.</p>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3132
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3133	<h5>Example:</h5>
				3134
				3135	<pre>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3136	%array = malloc [4 x i8 ] <i>; yields {[%4 x i8]*}:array</i>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3137
Bill Wendling	2d8b9a8	2007-05-29 09:42:13 +0000	[diff] [blame]	3138	%size = <a href="#i_add">add</a> i32 2, 2 <i>; yields {i32}:size = i32 4</i>
				3139	%array1 = malloc i8, i32 4 <i>; yields {i8*}:array1</i>
				3140	%array2 = malloc [12 x i8], i32 %size <i>; yields {[12 x i8]*}:array2</i>
				3141	%array3 = malloc i32, i32 4, align 1024 <i>; yields {i32*}:array3</i>
				3142	%array4 = malloc i32, align 1024 <i>; yields {i32*}:array4</i>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3143	</pre>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3144	</div>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3145
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3146	<!-- _______________________________________________________________________ -->
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3147	<div class="doc_subsubsection">
				3148	<a name="i_free">'<tt>free</tt>' Instruction</a>
				3149	</div>
				3150
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3151	<div class="doc_text">
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3152
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3153	<h5>Syntax:</h5>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3154
				3155	<pre>
				3156	free <type> <value> <i>; yields {void}</i>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3157	</pre>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3158
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3159	<h5>Overview:</h5>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3160
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	3161	<p>The '<tt>free</tt>' instruction returns memory back to the unused
John Criswell	4a3327e	2005-05-13 22:25:59 +0000	[diff] [blame]	3162	memory heap to be reallocated in the future.</p>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3163
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3164	<h5>Arguments:</h5>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3165
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	3166	<p>'<tt>value</tt>' shall be a pointer value that points to a value
				3167	that was allocated with the '<tt><a href="#i_malloc">malloc</a></tt>'
				3168	instruction.</p>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3169
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3170	<h5>Semantics:</h5>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3171
John Criswell	dfe6a86	2004-12-10 15:51:16 +0000	[diff] [blame]	3172	<p>Access to the memory pointed to by the pointer is no longer defined
Chris Lattner	0f103e1	2008-04-19 22:41:32 +0000	[diff] [blame]	3173	after this instruction executes. If the pointer is null, the operation
				3174	is a noop.</p>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3175
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3176	<h5>Example:</h5>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3177
				3178	<pre>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3179	%array = <a href="#i_malloc">malloc</a> [4 x i8] <i>; yields {[4 x i8]*}:array</i>
				3180	free [4 x i8]* %array
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3181	</pre>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3182	</div>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3183
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3184	<!-- _______________________________________________________________________ -->
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3185	<div class="doc_subsubsection">
				3186	<a name="i_alloca">'<tt>alloca</tt>' Instruction</a>
				3187	</div>
				3188
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3189	<div class="doc_text">
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3190
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3191	<h5>Syntax:</h5>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3192
				3193	<pre>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3194	<result> = alloca <type>[, i32 <NumElements>][, align <alignment>] <i>; yields {type*}:result</i>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3195	</pre>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3196
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3197	<h5>Overview:</h5>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3198
Jeff Cohen	5819f18	2007-04-22 01:17:39 +0000	[diff] [blame]	3199	<p>The '<tt>alloca</tt>' instruction allocates memory on the stack frame of the
				3200	currently executing function, to be automatically released when this function
Christopher Lamb	55c6d4f	2007-12-17 01:00:21 +0000	[diff] [blame]	3201	returns to its caller. The object is always allocated in the generic address
				3202	space (address space zero).</p>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3203
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3204	<h5>Arguments:</h5>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3205
John Criswell	dfe6a86	2004-12-10 15:51:16 +0000	[diff] [blame]	3206	<p>The '<tt>alloca</tt>' instruction allocates <tt>sizeof(<type>)*NumElements</tt>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	3207	bytes of memory on the runtime stack, returning a pointer of the
Gabor Greif	dd1fc98	2008-02-09 22:24:34 +0000	[diff] [blame]	3208	appropriate type to the program. If "NumElements" is specified, it is the
				3209	number of elements allocated, otherwise "NumElements" is defaulted to be one.
Chris Lattner	1f17cce	2008-04-02 00:38:26 +0000	[diff] [blame]	3210	If a constant alignment is specified, the value result of the allocation is guaranteed
Gabor Greif	dd1fc98	2008-02-09 22:24:34 +0000	[diff] [blame]	3211	to be aligned to at least that boundary. If not specified, or if zero, the target
				3212	can choose to align the allocation on any convenient boundary.</p>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3213
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3214	<p>'<tt>type</tt>' may be any sized type.</p>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3215
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3216	<h5>Semantics:</h5>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3217
Chris Lattner	fe8519c	2008-04-19 21:01:16 +0000	[diff] [blame]	3218	<p>Memory is allocated; a pointer is returned. The operation is undefiend if
				3219	there is insufficient stack space for the allocation. '<tt>alloca</tt>'d
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	3220	memory is automatically released when the function returns. The '<tt>alloca</tt>'
				3221	instruction is commonly used to represent automatic variables that must
				3222	have an address available. When the function returns (either with the <tt><a
John Criswell	c932bef	2005-05-12 16:55:34 +0000	[diff] [blame]	3223	href="#i_ret">ret</a></tt> or <tt><a href="#i_unwind">unwind</a></tt>
Chris Lattner	1f17cce	2008-04-02 00:38:26 +0000	[diff] [blame]	3224	instructions), the memory is reclaimed. Allocating zero bytes
				3225	is legal, but the result is undefined.</p>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3226
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3227	<h5>Example:</h5>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3228
				3229	<pre>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3230	%ptr = alloca i32 <i>; yields {i32*}:ptr</i>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	3231	%ptr = alloca i32, i32 4 <i>; yields {i32*}:ptr</i>
				3232	%ptr = alloca i32, i32 4, align 1024 <i>; yields {i32*}:ptr</i>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3233	%ptr = alloca i32, align 1024 <i>; yields {i32*}:ptr</i>
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3234	</pre>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3235	</div>
Chris Lattner	54611b4	2005-11-06 08:02:57 +0000	[diff] [blame]	3236
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3237	<!-- _______________________________________________________________________ -->
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	3238	<div class="doc_subsubsection"> <a name="i_load">'<tt>load</tt>'
				3239	Instruction</a> </div>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3240	<div class="doc_text">
Chris Lattner	095735d	2002-05-06 03:03:22 +0000	[diff] [blame]	3241	<h5>Syntax:</h5>
Christopher Lamb	bff5020	2007-04-21 08:16:25 +0000	[diff] [blame]	3242	<pre> <result> = load <ty>* <pointer>[, align <alignment>]<br> <result> = volatile load <ty>* <pointer>[, align <alignment>]<br></pre>
Chris Lattner	095735d	2002-05-06 03:03:22 +0000	[diff] [blame]	3243	<h5>Overview:</h5>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3244	<p>The '<tt>load</tt>' instruction is used to read from memory.</p>
Chris Lattner	095735d	2002-05-06 03:03:22 +0000	[diff] [blame]	3245	<h5>Arguments:</h5>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	3246	<p>The argument to the '<tt>load</tt>' instruction specifies the memory
John Criswell	4c0cf7f	2005-10-24 16:17:18 +0000	[diff] [blame]	3247	address from which to load. The pointer must point to a <a
Chris Lattner	10ee965	2004-06-03 22:57:15 +0000	[diff] [blame]	3248	href="#t_firstclass">first class</a> type. If the <tt>load</tt> is
John Criswell	4c0cf7f	2005-10-24 16:17:18 +0000	[diff] [blame]	3249	marked as <tt>volatile</tt>, then the optimizer is not allowed to modify
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	3250	the number or order of execution of this <tt>load</tt> with other
				3251	volatile <tt>load</tt> and <tt><a href="#i_store">store</a></tt>
				3252	instructions. </p>
Chris Lattner	2a1993f	2008-01-06 21:04:43 +0000	[diff] [blame]	3253	<p>
Chris Lattner	1f17cce	2008-04-02 00:38:26 +0000	[diff] [blame]	3254	The optional constant "align" argument specifies the alignment of the operation
Chris Lattner	2a1993f	2008-01-06 21:04:43 +0000	[diff] [blame]	3255	(that is, the alignment of the memory address). A value of 0 or an
				3256	omitted "align" argument means that the operation has the preferential
				3257	alignment for the target. It is the responsibility of the code emitter
				3258	to ensure that the alignment information is correct. Overestimating
				3259	the alignment results in an undefined behavior. Underestimating the
				3260	alignment may produce less efficient code. An alignment of 1 is always
				3261	safe.
				3262	</p>
Chris Lattner	095735d	2002-05-06 03:03:22 +0000	[diff] [blame]	3263	<h5>Semantics:</h5>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3264	<p>The location of memory pointed to is loaded.</p>
Chris Lattner	095735d	2002-05-06 03:03:22 +0000	[diff] [blame]	3265	<h5>Examples:</h5>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3266	<pre> %ptr = <a href="#i_alloca">alloca</a> i32 <i>; yields {i32*}:ptr</i>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	3267	<a
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3268	href="#i_store">store</a> i32 3, i32* %ptr <i>; yields {void}</i>
				3269	%val = load i32* %ptr <i>; yields {i32}:val = i32 3</i>
Chris Lattner	095735d	2002-05-06 03:03:22 +0000	[diff] [blame]	3270	</pre>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3271	</div>
Chris Lattner	095735d	2002-05-06 03:03:22 +0000	[diff] [blame]	3272	<!-- _______________________________________________________________________ -->
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	3273	<div class="doc_subsubsection"> <a name="i_store">'<tt>store</tt>'
				3274	Instruction</a> </div>
Reid Spencer	a89fb18	2006-11-09 21:18:01 +0000	[diff] [blame]	3275	<div class="doc_text">
Chris Lattner	095735d	2002-05-06 03:03:22 +0000	[diff] [blame]	3276	<h5>Syntax:</h5>
Christopher Lamb	bff5020	2007-04-21 08:16:25 +0000	[diff] [blame]	3277	<pre> store <ty> <value>, <ty>* <pointer>[, align <alignment>] <i>; yields {void}</i>
				3278	volatile store <ty> <value>, <ty>* <pointer>[, align <alignment>] <i>; yields {void}</i>
Chris Lattner	095735d	2002-05-06 03:03:22 +0000	[diff] [blame]	3279	</pre>
Chris Lattner	095735d	2002-05-06 03:03:22 +0000	[diff] [blame]	3280	<h5>Overview:</h5>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3281	<p>The '<tt>store</tt>' instruction is used to write to memory.</p>
Chris Lattner	095735d	2002-05-06 03:03:22 +0000	[diff] [blame]	3282	<h5>Arguments:</h5>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	3283	<p>There are two arguments to the '<tt>store</tt>' instruction: a value
Jeff Cohen	5819f18	2007-04-22 01:17:39 +0000	[diff] [blame]	3284	to store and an address at which to store it. The type of the '<tt><pointer></tt>'
Chris Lattner	1f17cce	2008-04-02 00:38:26 +0000	[diff] [blame]	3285	operand must be a pointer to the <a href="#t_firstclass">first class</a> type
				3286	of the '<tt><value></tt>'
John Criswell	4a3327e	2005-05-13 22:25:59 +0000	[diff] [blame]	3287	operand. If the <tt>store</tt> is marked as <tt>volatile</tt>, then the
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	3288	optimizer is not allowed to modify the number or order of execution of
				3289	this <tt>store</tt> with other volatile <tt>load</tt> and <tt><a
				3290	href="#i_store">store</a></tt> instructions.</p>
Chris Lattner	2a1993f	2008-01-06 21:04:43 +0000	[diff] [blame]	3291	<p>
Chris Lattner	1f17cce	2008-04-02 00:38:26 +0000	[diff] [blame]	3292	The optional constant "align" argument specifies the alignment of the operation
Chris Lattner	2a1993f	2008-01-06 21:04:43 +0000	[diff] [blame]	3293	(that is, the alignment of the memory address). A value of 0 or an
				3294	omitted "align" argument means that the operation has the preferential
				3295	alignment for the target. It is the responsibility of the code emitter
				3296	to ensure that the alignment information is correct. Overestimating
				3297	the alignment results in an undefined behavior. Underestimating the
				3298	alignment may produce less efficient code. An alignment of 1 is always
				3299	safe.
				3300	</p>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	3301	<h5>Semantics:</h5>
				3302	<p>The contents of memory are updated to contain '<tt><value></tt>'
				3303	at the location specified by the '<tt><pointer></tt>' operand.</p>
Chris Lattner	095735d	2002-05-06 03:03:22 +0000	[diff] [blame]	3304	<h5>Example:</h5>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3305	<pre> %ptr = <a href="#i_alloca">alloca</a> i32 <i>; yields {i32*}:ptr</i>
Bill Wendling	8830ffe	2007-10-22 05:10:05 +0000	[diff] [blame]	3306	store i32 3, i32* %ptr <i>; yields {void}</i>
				3307	%val = <a href="#i_load">load</a> i32* %ptr <i>; yields {i32}:val = i32 3</i>
Chris Lattner	095735d	2002-05-06 03:03:22 +0000	[diff] [blame]	3308	</pre>
Reid Spencer	443460a	2006-11-09 21:15:49 +0000	[diff] [blame]	3309	</div>
				3310
Chris Lattner	095735d	2002-05-06 03:03:22 +0000	[diff] [blame]	3311	<!-- _______________________________________________________________________ -->
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3312	<div class="doc_subsubsection">
				3313	<a name="i_getelementptr">'<tt>getelementptr</tt>' Instruction</a>
				3314	</div>
				3315
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3316	<div class="doc_text">
Chris Lattner	590645f	2002-04-14 06:13:44 +0000	[diff] [blame]	3317	<h5>Syntax:</h5>
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3318	<pre>
				3319	<result> = getelementptr <ty>* <ptrval>{, <ty> <idx>}*
				3320	</pre>
				3321
Chris Lattner	590645f	2002-04-14 06:13:44 +0000	[diff] [blame]	3322	<h5>Overview:</h5>
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3323
				3324	<p>
				3325	The '<tt>getelementptr</tt>' instruction is used to get the address of a
				3326	subelement of an aggregate data structure.</p>
				3327
Chris Lattner	590645f	2002-04-14 06:13:44 +0000	[diff] [blame]	3328	<h5>Arguments:</h5>
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3329
Reid Spencer	cee005c	2006-12-04 21:29:24 +0000	[diff] [blame]	3330	<p>This instruction takes a list of integer operands that indicate what
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3331	elements of the aggregate object to index to. The actual types of the arguments
				3332	provided depend on the type of the first pointer argument. The
				3333	'<tt>getelementptr</tt>' instruction is used to index down through the type
John Criswell	8819056	2005-05-16 16:17:45 +0000	[diff] [blame]	3334	levels of a structure or to a specific index in an array. When indexing into a
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3335	structure, only <tt>i32</tt> integer constants are allowed. When indexing
Chris Lattner	851b771	2008-04-24 05:59:56 +0000	[diff] [blame]	3336	into an array or pointer, only integers of 32 or 64 bits are allowed; 32-bit
				3337	values will be sign extended to 64-bits if required.</p>
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3338
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	3339	<p>For example, let's consider a C code fragment and how it gets
				3340	compiled to LLVM:</p>
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3341
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	3342	<div class="doc_code">
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3343	<pre>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	3344	struct RT {
				3345	char A;
Chris Lattner	a446f1b	2007-05-29 15:43:56 +0000	[diff] [blame]	3346	int B[10][20];
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	3347	char C;
				3348	};
				3349	struct ST {
Chris Lattner	a446f1b	2007-05-29 15:43:56 +0000	[diff] [blame]	3350	int X;
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	3351	double Y;
				3352	struct RT Z;
				3353	};
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3354
Chris Lattner	a446f1b	2007-05-29 15:43:56 +0000	[diff] [blame]	3355	int foo(struct ST s) {
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	3356	return &s[1].Z.B[5][13];
				3357	}
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3358	</pre>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	3359	</div>
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3360
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3361	<p>The LLVM code generated by the GCC frontend is:</p>
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3362
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	3363	<div class="doc_code">
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3364	<pre>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	3365	%RT = type { i8 , [10 x [20 x i32]], i8 }
				3366	%ST = type { i32, double, %RT }
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3367
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	3368	define i32* %foo(%ST* %s) {
				3369	entry:
				3370	%reg = getelementptr %ST* %s, i32 1, i32 2, i32 1, i32 5, i32 13
				3371	ret i32* %reg
				3372	}
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3373	</pre>
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	3374	</div>
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3375
Chris Lattner	590645f	2002-04-14 06:13:44 +0000	[diff] [blame]	3376	<h5>Semantics:</h5>
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3377
				3378	<p>The index types specified for the '<tt>getelementptr</tt>' instruction depend
John Criswell	4a3327e	2005-05-13 22:25:59 +0000	[diff] [blame]	3379	on the pointer type that is being indexed into. <a href="#t_pointer">Pointer</a>
Reid Spencer	cee005c	2006-12-04 21:29:24 +0000	[diff] [blame]	3380	and <a href="#t_array">array</a> types can use a 32-bit or 64-bit
Reid Spencer	c031269	2006-12-03 16:53:48 +0000	[diff] [blame]	3381	<a href="#t_integer">integer</a> type but the value will always be sign extended
Chris Lattner	1f17cce	2008-04-02 00:38:26 +0000	[diff] [blame]	3382	to 64-bits. <a href="#t_struct">Structure</a> and <a href="#t_pstruct">packed
				3383	structure</a> types require <tt>i32</tt> <b>constants</b>.</p>
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3384
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3385	<p>In the example above, the first index is indexing into the '<tt>%ST*</tt>'
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3386	type, which is a pointer, yielding a '<tt>%ST</tt>' = '<tt>{ i32, double, %RT
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3387	}</tt>' type, a structure. The second index indexes into the third element of
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3388	the structure, yielding a '<tt>%RT</tt>' = '<tt>{ i8 , [10 x [20 x i32]],
				3389	i8 }</tt>' type, another structure. The third index indexes into the second
				3390	element of the structure, yielding a '<tt>[10 x [20 x i32]]</tt>' type, an
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3391	array. The two dimensions of the array are subscripted into, yielding an
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3392	'<tt>i32</tt>' type. The '<tt>getelementptr</tt>' instruction returns a pointer
				3393	to this element, thus computing a value of '<tt>i32*</tt>' type.</p>
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3394
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	3395	<p>Note that it is perfectly legal to index partially through a
				3396	structure, returning a pointer to an inner element. Because of this,
				3397	the LLVM code for the given testcase is equivalent to:</p>
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3398
				3399	<pre>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3400	define i32* %foo(%ST* %s) {
				3401	%t1 = getelementptr %ST* %s, i32 1 <i>; yields %ST*:%t1</i>
Jeff Cohen	5819f18	2007-04-22 01:17:39 +0000	[diff] [blame]	3402	%t2 = getelementptr %ST* %t1, i32 0, i32 2 <i>; yields %RT*:%t2</i>
				3403	%t3 = getelementptr %RT* %t2, i32 0, i32 1 <i>; yields [10 x [20 x i32]]*:%t3</i>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3404	%t4 = getelementptr [10 x [20 x i32]]* %t3, i32 0, i32 5 <i>; yields [20 x i32]*:%t4</i>
				3405	%t5 = getelementptr [20 x i32]* %t4, i32 0, i32 13 <i>; yields i32*:%t5</i>
				3406	ret i32* %t5
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3407	}
Chris Lattner	a8292f3	2002-05-06 22:08:29 +0000	[diff] [blame]	3408	</pre>
Chris Lattner	c0ad71e	2005-06-24 17:22:57 +0000	[diff] [blame]	3409
				3410	<p>Note that it is undefined to access an array out of bounds: array and
				3411	pointer indexes must always be within the defined bounds of the array type.
Chris Lattner	851b771	2008-04-24 05:59:56 +0000	[diff] [blame]	3412	The one exception for this rule is zero length arrays. These arrays are
Chris Lattner	c0ad71e	2005-06-24 17:22:57 +0000	[diff] [blame]	3413	defined to be accessible as variable length arrays, which requires access
				3414	beyond the zero'th element.</p>
				3415
Chris Lattner	6ab6672	2006-08-15 00:45:58 +0000	[diff] [blame]	3416	<p>The getelementptr instruction is often confusing. For some more insight
				3417	into how it works, see <a href="GetElementPtr.html">the getelementptr
				3418	FAQ</a>.</p>
				3419
Chris Lattner	590645f	2002-04-14 06:13:44 +0000	[diff] [blame]	3420	<h5>Example:</h5>
Chris Lattner	c0ad71e	2005-06-24 17:22:57 +0000	[diff] [blame]	3421
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3422	<pre>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3423	<i>; yields [12 x i8]*:aptr</i>
				3424	%aptr = getelementptr {i32, [12 x i8]}* %sptr, i64 0, i32 1
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3425	</pre>
Chris Lattner	33fd702	2004-04-05 01:30:49 +0000	[diff] [blame]	3426	</div>
Reid Spencer	443460a	2006-11-09 21:15:49 +0000	[diff] [blame]	3427
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	3428	<!-- ======================================================================= -->
Reid Spencer	97c5fa4	2006-11-08 01:18:52 +0000	[diff] [blame]	3429	<div class="doc_subsection"> <a name="convertops">Conversion Operations</a>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3430	</div>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3431	<div class="doc_text">
Reid Spencer	97c5fa4	2006-11-08 01:18:52 +0000	[diff] [blame]	3432	<p>The instructions in this category are the conversion instructions (casting)
				3433	which all take a single operand and a type. They perform various bit conversions
				3434	on the operand.</p>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3435	</div>
Chris Lattner	b53c28d	2004-03-12 05:50:16 +0000	[diff] [blame]	3436
Chris Lattner	a8292f3	2002-05-06 22:08:29 +0000	[diff] [blame]	3437	<!-- _______________________________________________________________________ -->
Chris Lattner	b53c28d	2004-03-12 05:50:16 +0000	[diff] [blame]	3438	<div class="doc_subsubsection">
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3439	<a name="i_trunc">'<tt>trunc .. to</tt>' Instruction</a>
				3440	</div>
				3441	<div class="doc_text">
				3442
				3443	<h5>Syntax:</h5>
				3444	<pre>
				3445	<result> = trunc <ty> <value> to <ty2> <i>; yields ty2</i>
				3446	</pre>
				3447
				3448	<h5>Overview:</h5>
				3449	<p>
				3450	The '<tt>trunc</tt>' instruction truncates its operand to the type <tt>ty2</tt>.
				3451	</p>
				3452
				3453	<h5>Arguments:</h5>
				3454	<p>
				3455	The '<tt>trunc</tt>' instruction takes a <tt>value</tt> to trunc, which must
				3456	be an <a href="#t_integer">integer</a> type, and a type that specifies the size
Chris Lattner	c0f423a	2007-01-15 01:54:13 +0000	[diff] [blame]	3457	and type of the result, which must be an <a href="#t_integer">integer</a>
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	3458	type. The bit size of <tt>value</tt> must be larger than the bit size of
				3459	<tt>ty2</tt>. Equal sized types are not allowed.</p>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3460
				3461	<h5>Semantics:</h5>
				3462	<p>
				3463	The '<tt>trunc</tt>' instruction truncates the high order bits in <tt>value</tt>
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	3464	and converts the remaining bits to <tt>ty2</tt>. Since the source size must be
				3465	larger than the destination size, <tt>trunc</tt> cannot be a <i>no-op cast</i>.
				3466	It will always truncate bits.</p>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3467
				3468	<h5>Example:</h5>
				3469	<pre>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3470	%X = trunc i32 257 to i8 <i>; yields i8:1</i>
Reid Spencer	36a1542	2007-01-12 03:35:51 +0000	[diff] [blame]	3471	%Y = trunc i32 123 to i1 <i>; yields i1:true</i>
				3472	%Y = trunc i32 122 to i1 <i>; yields i1:false</i>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3473	</pre>
				3474	</div>
				3475
				3476	<!-- _______________________________________________________________________ -->
				3477	<div class="doc_subsubsection">
				3478	<a name="i_zext">'<tt>zext .. to</tt>' Instruction</a>
				3479	</div>
				3480	<div class="doc_text">
				3481
				3482	<h5>Syntax:</h5>
				3483	<pre>
				3484	<result> = zext <ty> <value> to <ty2> <i>; yields ty2</i>
				3485	</pre>
				3486
				3487	<h5>Overview:</h5>
				3488	<p>The '<tt>zext</tt>' instruction zero extends its operand to type
				3489	<tt>ty2</tt>.</p>
				3490
				3491
				3492	<h5>Arguments:</h5>
				3493	<p>The '<tt>zext</tt>' instruction takes a value to cast, which must be of
Chris Lattner	c0f423a	2007-01-15 01:54:13 +0000	[diff] [blame]	3494	<a href="#t_integer">integer</a> type, and a type to cast it to, which must
				3495	also be of <a href="#t_integer">integer</a> type. The bit size of the
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	3496	<tt>value</tt> must be smaller than the bit size of the destination type,
				3497	<tt>ty2</tt>.</p>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3498
				3499	<h5>Semantics:</h5>
				3500	<p>The <tt>zext</tt> fills the high order bits of the <tt>value</tt> with zero
Chris Lattner	c87f3df	2007-05-24 19:13:27 +0000	[diff] [blame]	3501	bits until it reaches the size of the destination type, <tt>ty2</tt>.</p>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3502
Reid Spencer	07c9c68	2007-01-12 15:46:11 +0000	[diff] [blame]	3503	<p>When zero extending from i1, the result will always be either 0 or 1.</p>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3504
				3505	<h5>Example:</h5>
				3506	<pre>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3507	%X = zext i32 257 to i64 <i>; yields i64:257</i>
Reid Spencer	36a1542	2007-01-12 03:35:51 +0000	[diff] [blame]	3508	%Y = zext i1 true to i32 <i>; yields i32:1</i>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3509	</pre>
				3510	</div>
				3511
				3512	<!-- _______________________________________________________________________ -->
				3513	<div class="doc_subsubsection">
				3514	<a name="i_sext">'<tt>sext .. to</tt>' Instruction</a>
				3515	</div>
				3516	<div class="doc_text">
				3517
				3518	<h5>Syntax:</h5>
				3519	<pre>
				3520	<result> = sext <ty> <value> to <ty2> <i>; yields ty2</i>
				3521	</pre>
				3522
				3523	<h5>Overview:</h5>
				3524	<p>The '<tt>sext</tt>' sign extends <tt>value</tt> to the type <tt>ty2</tt>.</p>
				3525
				3526	<h5>Arguments:</h5>
				3527	<p>
				3528	The '<tt>sext</tt>' instruction takes a value to cast, which must be of
Chris Lattner	c0f423a	2007-01-15 01:54:13 +0000	[diff] [blame]	3529	<a href="#t_integer">integer</a> type, and a type to cast it to, which must
				3530	also be of <a href="#t_integer">integer</a> type. The bit size of the
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	3531	<tt>value</tt> must be smaller than the bit size of the destination type,
				3532	<tt>ty2</tt>.</p>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3533
				3534	<h5>Semantics:</h5>
				3535	<p>
				3536	The '<tt>sext</tt>' instruction performs a sign extension by copying the sign
				3537	bit (highest order bit) of the <tt>value</tt> until it reaches the bit size of
Chris Lattner	c87f3df	2007-05-24 19:13:27 +0000	[diff] [blame]	3538	the type <tt>ty2</tt>.</p>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3539
Reid Spencer	36a1542	2007-01-12 03:35:51 +0000	[diff] [blame]	3540	<p>When sign extending from i1, the extension always results in -1 or 0.</p>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3541
				3542	<h5>Example:</h5>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3543	<pre>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3544	%X = sext i8 -1 to i16 <i>; yields i16 :65535</i>
Reid Spencer	36a1542	2007-01-12 03:35:51 +0000	[diff] [blame]	3545	%Y = sext i1 true to i32 <i>; yields i32:-1</i>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3546	</pre>
				3547	</div>
				3548
				3549	<!-- _______________________________________________________________________ -->
				3550	<div class="doc_subsubsection">
Reid Spencer	2e2740d	2006-11-09 21:48:10 +0000	[diff] [blame]	3551	<a name="i_fptrunc">'<tt>fptrunc .. to</tt>' Instruction</a>
				3552	</div>
				3553
				3554	<div class="doc_text">
				3555
				3556	<h5>Syntax:</h5>
				3557
				3558	<pre>
				3559	<result> = fptrunc <ty> <value> to <ty2> <i>; yields ty2</i>
				3560	</pre>
				3561
				3562	<h5>Overview:</h5>
				3563	<p>The '<tt>fptrunc</tt>' instruction truncates <tt>value</tt> to type
				3564	<tt>ty2</tt>.</p>
				3565
				3566
				3567	<h5>Arguments:</h5>
				3568	<p>The '<tt>fptrunc</tt>' instruction takes a <a href="#t_floating">floating
				3569	point</a> value to cast and a <a href="#t_floating">floating point</a> type to
				3570	cast it to. The size of <tt>value</tt> must be larger than the size of
				3571	<tt>ty2</tt>. This implies that <tt>fptrunc</tt> cannot be used to make a
				3572	<i>no-op cast</i>.</p>
				3573
				3574	<h5>Semantics:</h5>
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	3575	<p> The '<tt>fptrunc</tt>' instruction truncates a <tt>value</tt> from a larger
				3576	<a href="#t_floating">floating point</a> type to a smaller
				3577	<a href="#t_floating">floating point</a> type. If the value cannot fit within
				3578	the destination type, <tt>ty2</tt>, then the results are undefined.</p>
Reid Spencer	2e2740d	2006-11-09 21:48:10 +0000	[diff] [blame]	3579
				3580	<h5>Example:</h5>
				3581	<pre>
				3582	%X = fptrunc double 123.0 to float <i>; yields float:123.0</i>
				3583	%Y = fptrunc double 1.0E+300 to float <i>; yields undefined</i>
				3584	</pre>
				3585	</div>
				3586
				3587	<!-- _______________________________________________________________________ -->
				3588	<div class="doc_subsubsection">
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3589	<a name="i_fpext">'<tt>fpext .. to</tt>' Instruction</a>
				3590	</div>
				3591	<div class="doc_text">
				3592
				3593	<h5>Syntax:</h5>
				3594	<pre>
				3595	<result> = fpext <ty> <value> to <ty2> <i>; yields ty2</i>
				3596	</pre>
				3597
				3598	<h5>Overview:</h5>
				3599	<p>The '<tt>fpext</tt>' extends a floating point <tt>value</tt> to a larger
				3600	floating point value.</p>
				3601
				3602	<h5>Arguments:</h5>
				3603	<p>The '<tt>fpext</tt>' instruction takes a
				3604	<a href="#t_floating">floating point</a> <tt>value</tt> to cast,
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	3605	and a <a href="#t_floating">floating point</a> type to cast it to. The source
				3606	type must be smaller than the destination type.</p>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3607
				3608	<h5>Semantics:</h5>
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	3609	<p>The '<tt>fpext</tt>' instruction extends the <tt>value</tt> from a smaller
Duncan Sands	16f122e	2007-03-30 12:22:09 +0000	[diff] [blame]	3610	<a href="#t_floating">floating point</a> type to a larger
				3611	<a href="#t_floating">floating point</a> type. The <tt>fpext</tt> cannot be
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	3612	used to make a <i>no-op cast</i> because it always changes bits. Use
Reid Spencer	5b95064	2006-11-11 23:08:07 +0000	[diff] [blame]	3613	<tt>bitcast</tt> to make a <i>no-op cast</i> for a floating point cast.</p>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3614
				3615	<h5>Example:</h5>
				3616	<pre>
				3617	%X = fpext float 3.1415 to double <i>; yields double:3.1415</i>
				3618	%Y = fpext float 1.0 to float <i>; yields float:1.0 (no-op)</i>
				3619	</pre>
				3620	</div>
				3621
				3622	<!-- _______________________________________________________________________ -->
				3623	<div class="doc_subsubsection">
Reid Spencer	2eadb53	2007-01-21 00:29:26 +0000	[diff] [blame]	3624	<a name="i_fptoui">'<tt>fptoui .. to</tt>' Instruction</a>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3625	</div>
				3626	<div class="doc_text">
				3627
				3628	<h5>Syntax:</h5>
				3629	<pre>
Reid Spencer	753163d	2007-07-31 14:40:14 +0000	[diff] [blame]	3630	<result> = fptoui <ty> <value> to <ty2> <i>; yields ty2</i>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3631	</pre>
				3632
				3633	<h5>Overview:</h5>
Reid Spencer	753163d	2007-07-31 14:40:14 +0000	[diff] [blame]	3634	<p>The '<tt>fptoui</tt>' converts a floating point <tt>value</tt> to its
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3635	unsigned integer equivalent of type <tt>ty2</tt>.
				3636	</p>
				3637
				3638	<h5>Arguments:</h5>
Reid Spencer	753163d	2007-07-31 14:40:14 +0000	[diff] [blame]	3639	<p>The '<tt>fptoui</tt>' instruction takes a value to cast, which must be a
Nate Begeman	d4d45c2	2007-11-17 03:58:34 +0000	[diff] [blame]	3640	scalar or vector <a href="#t_floating">floating point</a> value, and a type
				3641	to cast it to <tt>ty2</tt>, which must be an <a href="#t_integer">integer</a>
				3642	type. If <tt>ty</tt> is a vector floating point type, <tt>ty2</tt> must be a
				3643	vector integer type with the same number of elements as <tt>ty</tt></p>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3644
				3645	<h5>Semantics:</h5>
Reid Spencer	753163d	2007-07-31 14:40:14 +0000	[diff] [blame]	3646	<p> The '<tt>fptoui</tt>' instruction converts its
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3647	<a href="#t_floating">floating point</a> operand into the nearest (rounding
				3648	towards zero) unsigned integer value. If the value cannot fit in <tt>ty2</tt>,
				3649	the results are undefined.</p>
				3650
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3651	<h5>Example:</h5>
				3652	<pre>
Reid Spencer	753163d	2007-07-31 14:40:14 +0000	[diff] [blame]	3653	%X = fptoui double 123.0 to i32 <i>; yields i32:123</i>
Chris Lattner	5b95a17	2007-09-22 03:17:52 +0000	[diff] [blame]	3654	%Y = fptoui float 1.0E+300 to i1 <i>; yields undefined:1</i>
Reid Spencer	753163d	2007-07-31 14:40:14 +0000	[diff] [blame]	3655	%X = fptoui float 1.04E+17 to i8 <i>; yields undefined:1</i>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3656	</pre>
				3657	</div>
				3658
				3659	<!-- _______________________________________________________________________ -->
				3660	<div class="doc_subsubsection">
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	3661	<a name="i_fptosi">'<tt>fptosi .. to</tt>' Instruction</a>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3662	</div>
				3663	<div class="doc_text">
				3664
				3665	<h5>Syntax:</h5>
				3666	<pre>
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	3667	<result> = fptosi <ty> <value> to <ty2> <i>; yields ty2</i>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3668	</pre>
				3669
				3670	<h5>Overview:</h5>
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	3671	<p>The '<tt>fptosi</tt>' instruction converts
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3672	<a href="#t_floating">floating point</a> <tt>value</tt> to type <tt>ty2</tt>.
Chris Lattner	b53c28d	2004-03-12 05:50:16 +0000	[diff] [blame]	3673	</p>
				3674
Chris Lattner	a8292f3	2002-05-06 22:08:29 +0000	[diff] [blame]	3675	<h5>Arguments:</h5>
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	3676	<p> The '<tt>fptosi</tt>' instruction takes a value to cast, which must be a
Nate Begeman	d4d45c2	2007-11-17 03:58:34 +0000	[diff] [blame]	3677	scalar or vector <a href="#t_floating">floating point</a> value, and a type
				3678	to cast it to <tt>ty2</tt>, which must be an <a href="#t_integer">integer</a>
				3679	type. If <tt>ty</tt> is a vector floating point type, <tt>ty2</tt> must be a
				3680	vector integer type with the same number of elements as <tt>ty</tt></p>
Chris Lattner	b53c28d	2004-03-12 05:50:16 +0000	[diff] [blame]	3681
Chris Lattner	a8292f3	2002-05-06 22:08:29 +0000	[diff] [blame]	3682	<h5>Semantics:</h5>
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	3683	<p>The '<tt>fptosi</tt>' instruction converts its
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3684	<a href="#t_floating">floating point</a> operand into the nearest (rounding
				3685	towards zero) signed integer value. If the value cannot fit in <tt>ty2</tt>,
				3686	the results are undefined.</p>
Chris Lattner	b53c28d	2004-03-12 05:50:16 +0000	[diff] [blame]	3687
Chris Lattner	70de663	2001-07-09 00:26:23 +0000	[diff] [blame]	3688	<h5>Example:</h5>
Chris Lattner	b53c28d	2004-03-12 05:50:16 +0000	[diff] [blame]	3689	<pre>
Reid Spencer	36a1542	2007-01-12 03:35:51 +0000	[diff] [blame]	3690	%X = fptosi double -123.0 to i32 <i>; yields i32:-123</i>
Chris Lattner	5b95a17	2007-09-22 03:17:52 +0000	[diff] [blame]	3691	%Y = fptosi float 1.0E-247 to i1 <i>; yields undefined:1</i>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3692	%X = fptosi float 1.04E+17 to i8 <i>; yields undefined:1</i>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3693	</pre>
				3694	</div>
				3695
				3696	<!-- _______________________________________________________________________ -->
				3697	<div class="doc_subsubsection">
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	3698	<a name="i_uitofp">'<tt>uitofp .. to</tt>' Instruction</a>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3699	</div>
				3700	<div class="doc_text">
				3701
				3702	<h5>Syntax:</h5>
				3703	<pre>
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	3704	<result> = uitofp <ty> <value> to <ty2> <i>; yields ty2</i>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3705	</pre>
				3706
				3707	<h5>Overview:</h5>
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	3708	<p>The '<tt>uitofp</tt>' instruction regards <tt>value</tt> as an unsigned
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3709	integer and converts that value to the <tt>ty2</tt> type.</p>
				3710
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3711	<h5>Arguments:</h5>
Nate Begeman	d4d45c2	2007-11-17 03:58:34 +0000	[diff] [blame]	3712	<p>The '<tt>uitofp</tt>' instruction takes a value to cast, which must be a
				3713	scalar or vector <a href="#t_integer">integer</a> value, and a type to cast it
				3714	to <tt>ty2</tt>, which must be an <a href="#t_floating">floating point</a>
				3715	type. If <tt>ty</tt> is a vector integer type, <tt>ty2</tt> must be a vector
				3716	floating point type with the same number of elements as <tt>ty</tt></p>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3717
				3718	<h5>Semantics:</h5>
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	3719	<p>The '<tt>uitofp</tt>' instruction interprets its operand as an unsigned
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3720	integer quantity and converts it to the corresponding floating point value. If
Jeff Cohen	beccb74	2007-04-22 14:56:37 +0000	[diff] [blame]	3721	the value cannot fit in the floating point value, the results are undefined.</p>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3722
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3723	<h5>Example:</h5>
				3724	<pre>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3725	%X = uitofp i32 257 to float <i>; yields float:257.0</i>
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	3726	%Y = uitofp i8 -1 to double <i>; yields double:255.0</i>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3727	</pre>
				3728	</div>
				3729
				3730	<!-- _______________________________________________________________________ -->
				3731	<div class="doc_subsubsection">
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	3732	<a name="i_sitofp">'<tt>sitofp .. to</tt>' Instruction</a>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3733	</div>
				3734	<div class="doc_text">
				3735
				3736	<h5>Syntax:</h5>
				3737	<pre>
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	3738	<result> = sitofp <ty> <value> to <ty2> <i>; yields ty2</i>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3739	</pre>
				3740
				3741	<h5>Overview:</h5>
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	3742	<p>The '<tt>sitofp</tt>' instruction regards <tt>value</tt> as a signed
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3743	integer and converts that value to the <tt>ty2</tt> type.</p>
				3744
				3745	<h5>Arguments:</h5>
Nate Begeman	d4d45c2	2007-11-17 03:58:34 +0000	[diff] [blame]	3746	<p>The '<tt>sitofp</tt>' instruction takes a value to cast, which must be a
				3747	scalar or vector <a href="#t_integer">integer</a> value, and a type to cast it
				3748	to <tt>ty2</tt>, which must be an <a href="#t_floating">floating point</a>
				3749	type. If <tt>ty</tt> is a vector integer type, <tt>ty2</tt> must be a vector
				3750	floating point type with the same number of elements as <tt>ty</tt></p>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3751
				3752	<h5>Semantics:</h5>
Reid Spencer	51b0725	2006-11-09 23:03:26 +0000	[diff] [blame]	3753	<p>The '<tt>sitofp</tt>' instruction interprets its operand as a signed
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3754	integer quantity and converts it to the corresponding floating point value. If
Jeff Cohen	beccb74	2007-04-22 14:56:37 +0000	[diff] [blame]	3755	the value cannot fit in the floating point value, the results are undefined.</p>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3756
				3757	<h5>Example:</h5>
				3758	<pre>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3759	%X = sitofp i32 257 to float <i>; yields float:257.0</i>
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	3760	%Y = sitofp i8 -1 to double <i>; yields double:-1.0</i>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3761	</pre>
				3762	</div>
				3763
				3764	<!-- _______________________________________________________________________ -->
				3765	<div class="doc_subsubsection">
Reid Spencer	b7344ff	2006-11-11 21:00:47 +0000	[diff] [blame]	3766	<a name="i_ptrtoint">'<tt>ptrtoint .. to</tt>' Instruction</a>
				3767	</div>
				3768	<div class="doc_text">
				3769
				3770	<h5>Syntax:</h5>
				3771	<pre>
				3772	<result> = ptrtoint <ty> <value> to <ty2> <i>; yields ty2</i>
				3773	</pre>
				3774
				3775	<h5>Overview:</h5>
				3776	<p>The '<tt>ptrtoint</tt>' instruction converts the pointer <tt>value</tt> to
				3777	the integer type <tt>ty2</tt>.</p>
				3778
				3779	<h5>Arguments:</h5>
				3780	<p>The '<tt>ptrtoint</tt>' instruction takes a <tt>value</tt> to cast, which
Duncan Sands	16f122e	2007-03-30 12:22:09 +0000	[diff] [blame]	3781	must be a <a href="#t_pointer">pointer</a> value, and a type to cast it to
Reid Spencer	b7344ff	2006-11-11 21:00:47 +0000	[diff] [blame]	3782	<tt>ty2</tt>, which must be an <a href="#t_integer">integer</a> type.
				3783
				3784	<h5>Semantics:</h5>
				3785	<p>The '<tt>ptrtoint</tt>' instruction converts <tt>value</tt> to integer type
				3786	<tt>ty2</tt> by interpreting the pointer value as an integer and either
				3787	truncating or zero extending that value to the size of the integer type. If
				3788	<tt>value</tt> is smaller than <tt>ty2</tt> then a zero extension is done. If
				3789	<tt>value</tt> is larger than <tt>ty2</tt> then a truncation is done. If they
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	3790	are the same size, then nothing is done (<i>no-op cast</i>) other than a type
				3791	change.</p>
Reid Spencer	b7344ff	2006-11-11 21:00:47 +0000	[diff] [blame]	3792
				3793	<h5>Example:</h5>
				3794	<pre>
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	3795	%X = ptrtoint i32* %X to i8 <i>; yields truncation on 32-bit architecture</i>
				3796	%Y = ptrtoint i32* %x to i64 <i>; yields zero extension on 32-bit architecture</i>
Reid Spencer	b7344ff	2006-11-11 21:00:47 +0000	[diff] [blame]	3797	</pre>
				3798	</div>
				3799
				3800	<!-- _______________________________________________________________________ -->
				3801	<div class="doc_subsubsection">
				3802	<a name="i_inttoptr">'<tt>inttoptr .. to</tt>' Instruction</a>
				3803	</div>
				3804	<div class="doc_text">
				3805
				3806	<h5>Syntax:</h5>
				3807	<pre>
				3808	<result> = inttoptr <ty> <value> to <ty2> <i>; yields ty2</i>
				3809	</pre>
				3810
				3811	<h5>Overview:</h5>
				3812	<p>The '<tt>inttoptr</tt>' instruction converts an integer <tt>value</tt> to
				3813	a pointer type, <tt>ty2</tt>.</p>
				3814
				3815	<h5>Arguments:</h5>
Duncan Sands	16f122e	2007-03-30 12:22:09 +0000	[diff] [blame]	3816	<p>The '<tt>inttoptr</tt>' instruction takes an <a href="#t_integer">integer</a>
Reid Spencer	b7344ff	2006-11-11 21:00:47 +0000	[diff] [blame]	3817	value to cast, and a type to cast it to, which must be a
Anton Korobeynikov	a0554d9	2007-01-12 19:20:47 +0000	[diff] [blame]	3818	<a href="#t_pointer">pointer</a> type.
Reid Spencer	b7344ff	2006-11-11 21:00:47 +0000	[diff] [blame]	3819
				3820	<h5>Semantics:</h5>
				3821	<p>The '<tt>inttoptr</tt>' instruction converts <tt>value</tt> to type
				3822	<tt>ty2</tt> by applying either a zero extension or a truncation depending on
				3823	the size of the integer <tt>value</tt>. If <tt>value</tt> is larger than the
				3824	size of a pointer then a truncation is done. If <tt>value</tt> is smaller than
				3825	the size of a pointer then a zero extension is done. If they are the same size,
				3826	nothing is done (<i>no-op cast</i>).</p>
				3827
				3828	<h5>Example:</h5>
				3829	<pre>
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	3830	%X = inttoptr i32 255 to i32* <i>; yields zero extension on 64-bit architecture</i>
				3831	%X = inttoptr i32 255 to i32* <i>; yields no-op on 32-bit architecture</i>
				3832	%Y = inttoptr i64 0 to i32* <i>; yields truncation on 32-bit architecture</i>
Reid Spencer	b7344ff	2006-11-11 21:00:47 +0000	[diff] [blame]	3833	</pre>
				3834	</div>
				3835
				3836	<!-- _______________________________________________________________________ -->
				3837	<div class="doc_subsubsection">
Reid Spencer	5b95064	2006-11-11 23:08:07 +0000	[diff] [blame]	3838	<a name="i_bitcast">'<tt>bitcast .. to</tt>' Instruction</a>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3839	</div>
				3840	<div class="doc_text">
				3841
				3842	<h5>Syntax:</h5>
				3843	<pre>
Reid Spencer	5b95064	2006-11-11 23:08:07 +0000	[diff] [blame]	3844	<result> = bitcast <ty> <value> to <ty2> <i>; yields ty2</i>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3845	</pre>
				3846
				3847	<h5>Overview:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	3848
Reid Spencer	5b95064	2006-11-11 23:08:07 +0000	[diff] [blame]	3849	<p>The '<tt>bitcast</tt>' instruction converts <tt>value</tt> to type
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3850	<tt>ty2</tt> without changing any bits.</p>
				3851
				3852	<h5>Arguments:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	3853
Reid Spencer	5b95064	2006-11-11 23:08:07 +0000	[diff] [blame]	3854	<p>The '<tt>bitcast</tt>' instruction takes a value to cast, which must be
Dan Gohman	c05dca9	2008-09-08 16:45:59 +0000	[diff] [blame]	3855	a non-aggregate first class value, and a type to cast it to, which must also be
				3856	a non-aggregate <a href="#t_firstclass">first class</a> type. The bit sizes of
				3857	<tt>value</tt>
Reid Spencer	e3db84c	2007-01-09 20:08:58 +0000	[diff] [blame]	3858	and the destination type, <tt>ty2</tt>, must be identical. If the source
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	3859	type is a pointer, the destination type must also be a pointer. This
				3860	instruction supports bitwise conversion of vectors to integers and to vectors
				3861	of other types (as long as they have the same size).</p>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3862
				3863	<h5>Semantics:</h5>
Reid Spencer	5b95064	2006-11-11 23:08:07 +0000	[diff] [blame]	3864	<p>The '<tt>bitcast</tt>' instruction converts <tt>value</tt> to type
Reid Spencer	b7344ff	2006-11-11 21:00:47 +0000	[diff] [blame]	3865	<tt>ty2</tt>. It is always a <i>no-op cast</i> because no bits change with
				3866	this conversion. The conversion is done as if the <tt>value</tt> had been
				3867	stored to memory and read back as type <tt>ty2</tt>. Pointer types may only be
				3868	converted to other pointer types with this instruction. To convert pointers to
				3869	other types, use the <a href="#i_inttoptr">inttoptr</a> or
				3870	<a href="#i_ptrtoint">ptrtoint</a> instructions first.</p>
Reid Spencer	59b6b7d	2006-11-08 01:11:31 +0000	[diff] [blame]	3871
				3872	<h5>Example:</h5>
				3873	<pre>
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	3874	%X = bitcast i8 255 to i8 <i>; yields i8 :-1</i>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3875	%Y = bitcast i32* %x to sint* <i>; yields sint*:%x</i>
				3876	%Z = bitcast <2xint> %V to i64; <i>; yields i64: %V</i>
Chris Lattner	70de663	2001-07-09 00:26:23 +0000	[diff] [blame]	3877	</pre>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	3878	</div>
Chris Lattner	b53c28d	2004-03-12 05:50:16 +0000	[diff] [blame]	3879
Reid Spencer	97c5fa4	2006-11-08 01:18:52 +0000	[diff] [blame]	3880	<!-- ======================================================================= -->
				3881	<div class="doc_subsection"> <a name="otherops">Other Operations</a> </div>
				3882	<div class="doc_text">
				3883	<p>The instructions in this category are the "miscellaneous"
				3884	instructions, which defy better classification.</p>
				3885	</div>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	3886
				3887	<!-- _______________________________________________________________________ -->
				3888	<div class="doc_subsubsection"><a name="i_icmp">'<tt>icmp</tt>' Instruction</a>
				3889	</div>
				3890	<div class="doc_text">
				3891	<h5>Syntax:</h5>
Dan Gohman	c579d97	2008-09-09 01:02:47 +0000	[diff] [blame]	3892	<pre> <result> = icmp <cond> <ty> <op1>, <op2> <i>; yields {i1} or {<N x i1&gt}:result</i>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	3893	</pre>
				3894	<h5>Overview:</h5>
Dan Gohman	c579d97	2008-09-09 01:02:47 +0000	[diff] [blame]	3895	<p>The '<tt>icmp</tt>' instruction returns a boolean value or
				3896	a vector of boolean values based on comparison
				3897	of its two integer, integer vector, or pointer operands.</p>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	3898	<h5>Arguments:</h5>
				3899	<p>The '<tt>icmp</tt>' instruction takes three operands. The first operand is
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	3900	the condition code indicating the kind of comparison to perform. It is not
				3901	a value, just a keyword. The possible condition code are:
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	3902	<ol>
				3903	<li><tt>eq</tt>: equal</li>
				3904	<li><tt>ne</tt>: not equal </li>
				3905	<li><tt>ugt</tt>: unsigned greater than</li>
				3906	<li><tt>uge</tt>: unsigned greater or equal</li>
				3907	<li><tt>ult</tt>: unsigned less than</li>
				3908	<li><tt>ule</tt>: unsigned less or equal</li>
				3909	<li><tt>sgt</tt>: signed greater than</li>
				3910	<li><tt>sge</tt>: signed greater or equal</li>
				3911	<li><tt>slt</tt>: signed less than</li>
				3912	<li><tt>sle</tt>: signed less or equal</li>
				3913	</ol>
Chris Lattner	c0f423a	2007-01-15 01:54:13 +0000	[diff] [blame]	3914	<p>The remaining two arguments must be <a href="#t_integer">integer</a> or
Dan Gohman	c579d97	2008-09-09 01:02:47 +0000	[diff] [blame]	3915	<a href="#t_pointer">pointer</a>
				3916	or integer <a href="#t_vector">vector</a> typed.
				3917	They must also be identical types.</p>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	3918	<h5>Semantics:</h5>
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	3919	<p>The '<tt>icmp</tt>' compares <tt>op1</tt> and <tt>op2</tt> according to
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	3920	the condition code given as <tt>cond</tt>. The comparison performed always
Dan Gohman	c579d97	2008-09-09 01:02:47 +0000	[diff] [blame]	3921	yields either an <a href="#t_primitive"><tt>i1</tt></a> or vector of <tt>i1</tt> result, as follows:
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	3922	<ol>
				3923	<li><tt>eq</tt>: yields <tt>true</tt> if the operands are equal,
				3924	<tt>false</tt> otherwise. No sign interpretation is necessary or performed.
				3925	</li>
				3926	<li><tt>ne</tt>: yields <tt>true</tt> if the operands are unequal,
				3927	<tt>false</tt> otherwise. No sign interpretation is necessary or performed.
				3928	<li><tt>ugt</tt>: interprets the operands as unsigned values and yields
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	3929	<tt>true</tt> if <tt>op1</tt> is greater than <tt>op2</tt>.</li>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	3930	<li><tt>uge</tt>: interprets the operands as unsigned values and yields
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	3931	<tt>true</tt> if <tt>op1</tt> is greater than or equal to <tt>op2</tt>.</li>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	3932	<li><tt>ult</tt>: interprets the operands as unsigned values and yields
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	3933	<tt>true</tt> if <tt>op1</tt> is less than <tt>op2</tt>.</li>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	3934	<li><tt>ule</tt>: interprets the operands as unsigned values and yields
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	3935	<tt>true</tt> if <tt>op1</tt> is less than or equal to <tt>op2</tt>.</li>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	3936	<li><tt>sgt</tt>: interprets the operands as signed values and yields
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	3937	<tt>true</tt> if <tt>op1</tt> is greater than <tt>op2</tt>.</li>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	3938	<li><tt>sge</tt>: interprets the operands as signed values and yields
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	3939	<tt>true</tt> if <tt>op1</tt> is greater than or equal to <tt>op2</tt>.</li>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	3940	<li><tt>slt</tt>: interprets the operands as signed values and yields
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	3941	<tt>true</tt> if <tt>op1</tt> is less than <tt>op2</tt>.</li>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	3942	<li><tt>sle</tt>: interprets the operands as signed values and yields
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	3943	<tt>true</tt> if <tt>op1</tt> is less than or equal to <tt>op2</tt>.</li>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	3944	</ol>
				3945	<p>If the operands are <a href="#t_pointer">pointer</a> typed, the pointer
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	3946	values are compared as if they were integers.</p>
Dan Gohman	c579d97	2008-09-09 01:02:47 +0000	[diff] [blame]	3947	<p>If the operands are integer vectors, then they are compared
				3948	element by element. The result is an <tt>i1</tt> vector with
				3949	the same number of elements as the values being compared.
				3950	Otherwise, the result is an <tt>i1</tt>.
				3951	</p>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	3952
				3953	<h5>Example:</h5>
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	3954	<pre> <result> = icmp eq i32 4, 5 <i>; yields: result=false</i>
				3955	<result> = icmp ne float* %X, %X <i>; yields: result=false</i>
				3956	<result> = icmp ult i16 4, 5 <i>; yields: result=true</i>
				3957	<result> = icmp sgt i16 4, 5 <i>; yields: result=false</i>
				3958	<result> = icmp ule i16 -4, 5 <i>; yields: result=false</i>
				3959	<result> = icmp sge i16 4, 5 <i>; yields: result=false</i>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	3960	</pre>
				3961	</div>
				3962
				3963	<!-- _______________________________________________________________________ -->
				3964	<div class="doc_subsubsection"><a name="i_fcmp">'<tt>fcmp</tt>' Instruction</a>
				3965	</div>
				3966	<div class="doc_text">
				3967	<h5>Syntax:</h5>
Dan Gohman	c579d97	2008-09-09 01:02:47 +0000	[diff] [blame]	3968	<pre> <result> = fcmp <cond> <ty> <op1>, <op2> <i>; yields {i1} or {<N x i1&gt}:result</i>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	3969	</pre>
				3970	<h5>Overview:</h5>
Dan Gohman	c579d97	2008-09-09 01:02:47 +0000	[diff] [blame]	3971	<p>The '<tt>fcmp</tt>' instruction returns a boolean value
				3972	or vector of boolean values based on comparison
				3973	of its operands.
				3974	<p>
				3975	If the operands are floating point scalars, then the result
				3976	type is a boolean (<a href="#t_primitive"><tt>i1</tt></a>).
				3977	</p>
				3978	<p>If the operands are floating point vectors, then the result type
				3979	is a vector of boolean with the same number of elements as the
				3980	operands being compared.</p>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	3981	<h5>Arguments:</h5>
				3982	<p>The '<tt>fcmp</tt>' instruction takes three operands. The first operand is
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	3983	the condition code indicating the kind of comparison to perform. It is not
				3984	a value, just a keyword. The possible condition code are:
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	3985	<ol>
Reid Spencer	f69acf3	2006-11-19 03:00:14 +0000	[diff] [blame]	3986	<li><tt>false</tt>: no comparison, always returns false</li>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	3987	<li><tt>oeq</tt>: ordered and equal</li>
				3988	<li><tt>ogt</tt>: ordered and greater than </li>
				3989	<li><tt>oge</tt>: ordered and greater than or equal</li>
				3990	<li><tt>olt</tt>: ordered and less than </li>
				3991	<li><tt>ole</tt>: ordered and less than or equal</li>
				3992	<li><tt>one</tt>: ordered and not equal</li>
				3993	<li><tt>ord</tt>: ordered (no nans)</li>
				3994	<li><tt>ueq</tt>: unordered or equal</li>
				3995	<li><tt>ugt</tt>: unordered or greater than </li>
				3996	<li><tt>uge</tt>: unordered or greater than or equal</li>
				3997	<li><tt>ult</tt>: unordered or less than </li>
				3998	<li><tt>ule</tt>: unordered or less than or equal</li>
				3999	<li><tt>une</tt>: unordered or not equal</li>
				4000	<li><tt>uno</tt>: unordered (either nans)</li>
Reid Spencer	f69acf3	2006-11-19 03:00:14 +0000	[diff] [blame]	4001	<li><tt>true</tt>: no comparison, always returns true</li>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	4002	</ol>
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	4003	<p><i>Ordered</i> means that neither operand is a QNAN while
Reid Spencer	02e0d1d	2006-12-06 07:08:07 +0000	[diff] [blame]	4004	<i>unordered</i> means that either operand may be a QNAN.</p>
Dan Gohman	c579d97	2008-09-09 01:02:47 +0000	[diff] [blame]	4005	<p>Each of <tt>val1</tt> and <tt>val2</tt> arguments must be
				4006	either a <a href="#t_floating">floating point</a> type
				4007	or a <a href="#t_vector">vector</a> of floating point type.
				4008	They must have identical types.</p>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	4009	<h5>Semantics:</h5>
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	4010	<p>The '<tt>fcmp</tt>' instruction compares <tt>op1</tt> and <tt>op2</tt>
Dan Gohman	c579d97	2008-09-09 01:02:47 +0000	[diff] [blame]	4011	according to the condition code given as <tt>cond</tt>.
				4012	If the operands are vectors, then the vectors are compared
				4013	element by element.
				4014	Each comparison performed
				4015	always yields an <a href="#t_primitive">i1</a> result, as follows:
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	4016	<ol>
				4017	<li><tt>false</tt>: always yields <tt>false</tt>, regardless of operands.</li>
Reid Spencer	f69acf3	2006-11-19 03:00:14 +0000	[diff] [blame]	4018	<li><tt>oeq</tt>: yields <tt>true</tt> if both operands are not a QNAN and
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	4019	<tt>op1</tt> is equal to <tt>op2</tt>.</li>
Reid Spencer	f69acf3	2006-11-19 03:00:14 +0000	[diff] [blame]	4020	<li><tt>ogt</tt>: yields <tt>true</tt> if both operands are not a QNAN and
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	4021	<tt>op1</tt> is greather than <tt>op2</tt>.</li>
Reid Spencer	f69acf3	2006-11-19 03:00:14 +0000	[diff] [blame]	4022	<li><tt>oge</tt>: yields <tt>true</tt> if both operands are not a QNAN and
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	4023	<tt>op1</tt> is greater than or equal to <tt>op2</tt>.</li>
Reid Spencer	f69acf3	2006-11-19 03:00:14 +0000	[diff] [blame]	4024	<li><tt>olt</tt>: yields <tt>true</tt> if both operands are not a QNAN and
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	4025	<tt>op1</tt> is less than <tt>op2</tt>.</li>
Reid Spencer	f69acf3	2006-11-19 03:00:14 +0000	[diff] [blame]	4026	<li><tt>ole</tt>: yields <tt>true</tt> if both operands are not a QNAN and
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	4027	<tt>op1</tt> is less than or equal to <tt>op2</tt>.</li>
Reid Spencer	f69acf3	2006-11-19 03:00:14 +0000	[diff] [blame]	4028	<li><tt>one</tt>: yields <tt>true</tt> if both operands are not a QNAN and
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	4029	<tt>op1</tt> is not equal to <tt>op2</tt>.</li>
Reid Spencer	f69acf3	2006-11-19 03:00:14 +0000	[diff] [blame]	4030	<li><tt>ord</tt>: yields <tt>true</tt> if both operands are not a QNAN.</li>
				4031	<li><tt>ueq</tt>: yields <tt>true</tt> if either operand is a QNAN or
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	4032	<tt>op1</tt> is equal to <tt>op2</tt>.</li>
Reid Spencer	f69acf3	2006-11-19 03:00:14 +0000	[diff] [blame]	4033	<li><tt>ugt</tt>: yields <tt>true</tt> if either operand is a QNAN or
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	4034	<tt>op1</tt> is greater than <tt>op2</tt>.</li>
Reid Spencer	f69acf3	2006-11-19 03:00:14 +0000	[diff] [blame]	4035	<li><tt>uge</tt>: yields <tt>true</tt> if either operand is a QNAN or
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	4036	<tt>op1</tt> is greater than or equal to <tt>op2</tt>.</li>
Reid Spencer	f69acf3	2006-11-19 03:00:14 +0000	[diff] [blame]	4037	<li><tt>ult</tt>: yields <tt>true</tt> if either operand is a QNAN or
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	4038	<tt>op1</tt> is less than <tt>op2</tt>.</li>
Reid Spencer	f69acf3	2006-11-19 03:00:14 +0000	[diff] [blame]	4039	<li><tt>ule</tt>: yields <tt>true</tt> if either operand is a QNAN or
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	4040	<tt>op1</tt> is less than or equal to <tt>op2</tt>.</li>
Reid Spencer	f69acf3	2006-11-19 03:00:14 +0000	[diff] [blame]	4041	<li><tt>une</tt>: yields <tt>true</tt> if either operand is a QNAN or
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	4042	<tt>op1</tt> is not equal to <tt>op2</tt>.</li>
Reid Spencer	f69acf3	2006-11-19 03:00:14 +0000	[diff] [blame]	4043	<li><tt>uno</tt>: yields <tt>true</tt> if either operand is a QNAN.</li>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	4044	<li><tt>true</tt>: always yields <tt>true</tt>, regardless of operands.</li>
				4045	</ol>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	4046
				4047	<h5>Example:</h5>
				4048	<pre> <result> = fcmp oeq float 4.0, 5.0 <i>; yields: result=false</i>
Dan Gohman	c579d97	2008-09-09 01:02:47 +0000	[diff] [blame]	4049	<result> = fcmp one float 4.0, 5.0 <i>; yields: result=true</i>
				4050	<result> = fcmp olt float 4.0, 5.0 <i>; yields: result=true</i>
				4051	<result> = fcmp ueq double 1.0, 2.0 <i>; yields: result=false</i>
Reid Spencer	c828a0e	2006-11-18 21:50:54 +0000	[diff] [blame]	4052	</pre>
				4053	</div>
				4054
Reid Spencer	97c5fa4	2006-11-08 01:18:52 +0000	[diff] [blame]	4055	<!-- _______________________________________________________________________ -->
Nate Begeman	d219570	2008-05-12 19:01:56 +0000	[diff] [blame]	4056	<div class="doc_subsubsection">
				4057	<a name="i_vicmp">'<tt>vicmp</tt>' Instruction</a>
				4058	</div>
				4059	<div class="doc_text">
				4060	<h5>Syntax:</h5>
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	4061	<pre> <result> = vicmp <cond> <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Nate Begeman	d219570	2008-05-12 19:01:56 +0000	[diff] [blame]	4062	</pre>
				4063	<h5>Overview:</h5>
				4064	<p>The '<tt>vicmp</tt>' instruction returns an integer vector value based on
				4065	element-wise comparison of its two integer vector operands.</p>
				4066	<h5>Arguments:</h5>
				4067	<p>The '<tt>vicmp</tt>' instruction takes three operands. The first operand is
				4068	the condition code indicating the kind of comparison to perform. It is not
				4069	a value, just a keyword. The possible condition code are:
				4070	<ol>
				4071	<li><tt>eq</tt>: equal</li>
				4072	<li><tt>ne</tt>: not equal </li>
				4073	<li><tt>ugt</tt>: unsigned greater than</li>
				4074	<li><tt>uge</tt>: unsigned greater or equal</li>
				4075	<li><tt>ult</tt>: unsigned less than</li>
				4076	<li><tt>ule</tt>: unsigned less or equal</li>
				4077	<li><tt>sgt</tt>: signed greater than</li>
				4078	<li><tt>sge</tt>: signed greater or equal</li>
				4079	<li><tt>slt</tt>: signed less than</li>
				4080	<li><tt>sle</tt>: signed less or equal</li>
				4081	</ol>
Dan Gohman	c579d97	2008-09-09 01:02:47 +0000	[diff] [blame]	4082	<p>The remaining two arguments must be <a href="#t_vector">vector</a> or
Nate Begeman	d219570	2008-05-12 19:01:56 +0000	[diff] [blame]	4083	<a href="#t_integer">integer</a> typed. They must also be identical types.</p>
				4084	<h5>Semantics:</h5>
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	4085	<p>The '<tt>vicmp</tt>' instruction compares <tt>op1</tt> and <tt>op2</tt>
Nate Begeman	d219570	2008-05-12 19:01:56 +0000	[diff] [blame]	4086	according to the condition code given as <tt>cond</tt>. The comparison yields a
				4087	<a href="#t_vector">vector</a> of <a href="#t_integer">integer</a> result, of
				4088	identical type as the values being compared. The most significant bit in each
				4089	element is 1 if the element-wise comparison evaluates to true, and is 0
				4090	otherwise. All other bits of the result are undefined. The condition codes
				4091	are evaluated identically to the <a href="#i_icmp">'<tt>icmp</tt>'
				4092	instruction</a>.
				4093
				4094	<h5>Example:</h5>
				4095	<pre>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	4096	<result> = vicmp eq <2 x i32> < i32 4, i32 0>, < i32 5, i32 0> <i>; yields: result=<2 x i32> < i32 0, i32 -1 ></i>
				4097	<result> = vicmp ult <2 x i8 > < i8 1, i8 2>, < i8 2, i8 2 > <i>; yields: result=<2 x i8> < i8 -1, i8 0 ></i>
Nate Begeman	d219570	2008-05-12 19:01:56 +0000	[diff] [blame]	4098	</pre>
				4099	</div>
				4100
				4101	<!-- _______________________________________________________________________ -->
				4102	<div class="doc_subsubsection">
				4103	<a name="i_vfcmp">'<tt>vfcmp</tt>' Instruction</a>
				4104	</div>
				4105	<div class="doc_text">
				4106	<h5>Syntax:</h5>
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	4107	<pre> <result> = vfcmp <cond> <ty> <op1>, <op2></pre>
Nate Begeman	d219570	2008-05-12 19:01:56 +0000	[diff] [blame]	4108	<h5>Overview:</h5>
				4109	<p>The '<tt>vfcmp</tt>' instruction returns an integer vector value based on
				4110	element-wise comparison of its two floating point vector operands. The output
				4111	elements have the same width as the input elements.</p>
				4112	<h5>Arguments:</h5>
				4113	<p>The '<tt>vfcmp</tt>' instruction takes three operands. The first operand is
				4114	the condition code indicating the kind of comparison to perform. It is not
				4115	a value, just a keyword. The possible condition code are:
				4116	<ol>
				4117	<li><tt>false</tt>: no comparison, always returns false</li>
				4118	<li><tt>oeq</tt>: ordered and equal</li>
				4119	<li><tt>ogt</tt>: ordered and greater than </li>
				4120	<li><tt>oge</tt>: ordered and greater than or equal</li>
				4121	<li><tt>olt</tt>: ordered and less than </li>
				4122	<li><tt>ole</tt>: ordered and less than or equal</li>
				4123	<li><tt>one</tt>: ordered and not equal</li>
				4124	<li><tt>ord</tt>: ordered (no nans)</li>
				4125	<li><tt>ueq</tt>: unordered or equal</li>
				4126	<li><tt>ugt</tt>: unordered or greater than </li>
				4127	<li><tt>uge</tt>: unordered or greater than or equal</li>
				4128	<li><tt>ult</tt>: unordered or less than </li>
				4129	<li><tt>ule</tt>: unordered or less than or equal</li>
				4130	<li><tt>une</tt>: unordered or not equal</li>
				4131	<li><tt>uno</tt>: unordered (either nans)</li>
				4132	<li><tt>true</tt>: no comparison, always returns true</li>
				4133	</ol>
				4134	<p>The remaining two arguments must be <a href="#t_vector">vector</a> of
				4135	<a href="#t_floating">floating point</a> typed. They must also be identical
				4136	types.</p>
				4137	<h5>Semantics:</h5>
Gabor Greif	0f75ad0	2008-08-07 21:46:00 +0000	[diff] [blame]	4138	<p>The '<tt>vfcmp</tt>' instruction compares <tt>op1</tt> and <tt>op2</tt>
Nate Begeman	d219570	2008-05-12 19:01:56 +0000	[diff] [blame]	4139	according to the condition code given as <tt>cond</tt>. The comparison yields a
				4140	<a href="#t_vector">vector</a> of <a href="#t_integer">integer</a> result, with
				4141	an identical number of elements as the values being compared, and each element
				4142	having identical with to the width of the floating point elements. The most
				4143	significant bit in each element is 1 if the element-wise comparison evaluates to
				4144	true, and is 0 otherwise. All other bits of the result are undefined. The
				4145	condition codes are evaluated identically to the
				4146	<a href="#i_fcmp">'<tt>fcmp</tt>' instruction</a>.
				4147
				4148	<h5>Example:</h5>
				4149	<pre>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	4150	<result> = vfcmp oeq <2 x float> < float 4, float 0 >, < float 5, float 0 > <i>; yields: result=<2 x i32> < i32 0, i32 -1 ></i>
				4151	<result> = vfcmp ult <2 x double> < double 1, double 2 >, < double 2, double 2> <i>; yields: result=<2 x i64> < i64 -1, i64 0 ></i>
Nate Begeman	d219570	2008-05-12 19:01:56 +0000	[diff] [blame]	4152	</pre>
				4153	</div>
				4154
				4155	<!-- _______________________________________________________________________ -->
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	4156	<div class="doc_subsubsection">
				4157	<a name="i_phi">'<tt>phi</tt>' Instruction</a>
				4158	</div>
				4159
Reid Spencer	97c5fa4	2006-11-08 01:18:52 +0000	[diff] [blame]	4160	<div class="doc_text">
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	4161
Reid Spencer	97c5fa4	2006-11-08 01:18:52 +0000	[diff] [blame]	4162	<h5>Syntax:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	4163
Reid Spencer	97c5fa4	2006-11-08 01:18:52 +0000	[diff] [blame]	4164	<pre> <result> = phi <ty> [ <val0>, <label0>], ...<br></pre>
				4165	<h5>Overview:</h5>
				4166	<p>The '<tt>phi</tt>' instruction is used to implement the φ node in
				4167	the SSA graph representing the function.</p>
				4168	<h5>Arguments:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	4169
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	4170	<p>The type of the incoming values is specified with the first type
Reid Spencer	97c5fa4	2006-11-08 01:18:52 +0000	[diff] [blame]	4171	field. After this, the '<tt>phi</tt>' instruction takes a list of pairs
				4172	as arguments, with one pair for each predecessor basic block of the
				4173	current block. Only values of <a href="#t_firstclass">first class</a>
				4174	type may be used as the value arguments to the PHI node. Only labels
				4175	may be used as the label arguments.</p>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	4176
Reid Spencer	97c5fa4	2006-11-08 01:18:52 +0000	[diff] [blame]	4177	<p>There must be no non-phi instructions between the start of a basic
				4178	block and the PHI instructions: i.e. PHI instructions must be first in
				4179	a basic block.</p>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	4180
Reid Spencer	97c5fa4	2006-11-08 01:18:52 +0000	[diff] [blame]	4181	<h5>Semantics:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	4182
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	4183	<p>At runtime, the '<tt>phi</tt>' instruction logically takes on the value
				4184	specified by the pair corresponding to the predecessor basic block that executed
				4185	just prior to the current block.</p>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	4186
Reid Spencer	97c5fa4	2006-11-08 01:18:52 +0000	[diff] [blame]	4187	<h5>Example:</h5>
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	4188	<pre>
				4189	Loop: ; Infinite loop that counts from 0 on up...
				4190	%indvar = phi i32 [ 0, %LoopHeader ], [ %nextindvar, %Loop ]
				4191	%nextindvar = add i32 %indvar, 1
				4192	br label %Loop
				4193	</pre>
Reid Spencer	97c5fa4	2006-11-08 01:18:52 +0000	[diff] [blame]	4194	</div>
				4195
Chris Lattner	b53c28d	2004-03-12 05:50:16 +0000	[diff] [blame]	4196	<!-- _______________________________________________________________________ -->
				4197	<div class="doc_subsubsection">
				4198	<a name="i_select">'<tt>select</tt>' Instruction</a>
				4199	</div>
				4200
				4201	<div class="doc_text">
				4202
				4203	<h5>Syntax:</h5>
				4204
				4205	<pre>
Dan Gohman	c579d97	2008-09-09 01:02:47 +0000	[diff] [blame]	4206	<result> = select <i>selty</i> <cond>, <ty> <val1>, <ty> <val2> <i>; yields ty</i>
				4207
				4208	<i>selty</i> is either i1 or {<N x i1&gt}
Chris Lattner	b53c28d	2004-03-12 05:50:16 +0000	[diff] [blame]	4209	</pre>
				4210
				4211	<h5>Overview:</h5>
				4212
				4213	<p>
				4214	The '<tt>select</tt>' instruction is used to choose one value based on a
				4215	condition, without branching.
				4216	</p>
				4217
				4218
				4219	<h5>Arguments:</h5>
				4220
				4221	<p>
Dan Gohman	c579d97	2008-09-09 01:02:47 +0000	[diff] [blame]	4222	The '<tt>select</tt>' instruction requires an 'i1' value or
				4223	a vector of 'i1' values indicating the
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	4224	condition, and two values of the same <a href="#t_firstclass">first class</a>
Dan Gohman	c579d97	2008-09-09 01:02:47 +0000	[diff] [blame]	4225	type. If the val1/val2 are vectors and
				4226	the condition is a scalar, then entire vectors are selected, not
Chris Lattner	b54c30f	2008-05-20 20:48:21 +0000	[diff] [blame]	4227	individual elements.
Chris Lattner	b53c28d	2004-03-12 05:50:16 +0000	[diff] [blame]	4228	</p>
				4229
				4230	<h5>Semantics:</h5>
				4231
				4232	<p>
Dan Gohman	c579d97	2008-09-09 01:02:47 +0000	[diff] [blame]	4233	If the condition is an i1 and it evaluates to 1, the instruction returns the first
John Criswell	8819056	2005-05-16 16:17:45 +0000	[diff] [blame]	4234	value argument; otherwise, it returns the second value argument.
Chris Lattner	b53c28d	2004-03-12 05:50:16 +0000	[diff] [blame]	4235	</p>
Dan Gohman	c579d97	2008-09-09 01:02:47 +0000	[diff] [blame]	4236	<p>
				4237	If the condition is a vector of i1, then the value arguments must
				4238	be vectors of the same size, and the selection is done element
				4239	by element.
				4240	</p>
Chris Lattner	b53c28d	2004-03-12 05:50:16 +0000	[diff] [blame]	4241
				4242	<h5>Example:</h5>
				4243
				4244	<pre>
Reid Spencer	36a1542	2007-01-12 03:35:51 +0000	[diff] [blame]	4245	%X = select i1 true, i8 17, i8 42 <i>; yields i8:17</i>
Chris Lattner	b53c28d	2004-03-12 05:50:16 +0000	[diff] [blame]	4246	</pre>
				4247	</div>
				4248
Robert Bocchino	f72fdfe	2006-01-15 20:48:27 +0000	[diff] [blame]	4249
				4250	<!-- _______________________________________________________________________ -->
				4251	<div class="doc_subsubsection">
Chris Lattner	e23c139	2005-05-06 05:47:36 +0000	[diff] [blame]	4252	<a name="i_call">'<tt>call</tt>' Instruction</a>
				4253	</div>
				4254
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	4255	<div class="doc_text">
Chris Lattner	e23c139	2005-05-06 05:47:36 +0000	[diff] [blame]	4256
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	4257	<h5>Syntax:</h5>
Chris Lattner	e23c139	2005-05-06 05:47:36 +0000	[diff] [blame]	4258	<pre>
Devang Patel	0225623	2008-10-07 17:48:33 +0000	[diff] [blame]	4259	<result> = [tail] call [<a href="#callingconv">cconv</a>] [<a href="#paramattrs">ret attrs</a>] <ty> [<fnty>*] <fnptrval>(<function args>) [<a href="#fnattrs">fn attrs</a>]
Chris Lattner	e23c139	2005-05-06 05:47:36 +0000	[diff] [blame]	4260	</pre>
				4261
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	4262	<h5>Overview:</h5>
Chris Lattner	e23c139	2005-05-06 05:47:36 +0000	[diff] [blame]	4263
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	4264	<p>The '<tt>call</tt>' instruction represents a simple function call.</p>
Chris Lattner	e23c139	2005-05-06 05:47:36 +0000	[diff] [blame]	4265
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	4266	<h5>Arguments:</h5>
Chris Lattner	e23c139	2005-05-06 05:47:36 +0000	[diff] [blame]	4267
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	4268	<p>This instruction requires several arguments:</p>
Chris Lattner	e23c139	2005-05-06 05:47:36 +0000	[diff] [blame]	4269
Chris Lattner	a8292f3	2002-05-06 22:08:29 +0000	[diff] [blame]	4270	<ol>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	4271	<li>
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	4272	<p>The optional "tail" marker indicates whether the callee function accesses
				4273	any allocas or varargs in the caller. If the "tail" marker is present, the
Chris Lattner	e23c139	2005-05-06 05:47:36 +0000	[diff] [blame]	4274	function call is eligible for tail call optimization. Note that calls may
				4275	be marked "tail" even if they do not occur before a <a
				4276	href="#i_ret"><tt>ret</tt></a> instruction.
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	4277	</li>
				4278	<li>
Duncan Sands	16f122e	2007-03-30 12:22:09 +0000	[diff] [blame]	4279	<p>The optional "cconv" marker indicates which <a href="#callingconv">calling
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	4280	convention</a> the call should use. If none is specified, the call defaults
				4281	to using C calling conventions.
				4282	</li>
Devang Patel	7e9b05e	2008-10-06 18:50:38 +0000	[diff] [blame]	4283
				4284	<li>
				4285	<p>The optional <a href="#paramattrs">Parameter Attributes</a> list for
				4286	return values. Only '<tt>zeroext</tt>', '<tt>signext</tt>',
				4287	and '<tt>inreg</tt>' attributes are valid here.</p>
				4288	</li>
				4289
Chris Lattner	0132aff	2005-05-06 22:57:40 +0000	[diff] [blame]	4290	<li>
Nick Lewycky	a9b13d5	2007-09-08 13:57:50 +0000	[diff] [blame]	4291	<p>'<tt>ty</tt>': the type of the call instruction itself which is also
				4292	the type of the return value. Functions that return no value are marked
				4293	<tt><a href="#t_void">void</a></tt>.</p>
				4294	</li>
				4295	<li>
				4296	<p>'<tt>fnty</tt>': shall be the signature of the pointer to function
				4297	value being invoked. The argument types must match the types implied by
				4298	this signature. This type can be omitted if the function is not varargs
				4299	and if the function type does not return a pointer to a function.</p>
Chris Lattner	e23c139	2005-05-06 05:47:36 +0000	[diff] [blame]	4300	</li>
				4301	<li>
				4302	<p>'<tt>fnptrval</tt>': An LLVM value containing a pointer to a function to
				4303	be invoked. In most cases, this is a direct function invocation, but
				4304	indirect <tt>call</tt>s are just as possible, calling an arbitrary pointer
John Criswell	8819056	2005-05-16 16:17:45 +0000	[diff] [blame]	4305	to function value.</p>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	4306	</li>
				4307	<li>
				4308	<p>'<tt>function args</tt>': argument list whose types match the
Reid Spencer	d845d16	2005-05-01 22:22:57 +0000	[diff] [blame]	4309	function signature argument types. All arguments must be of
				4310	<a href="#t_firstclass">first class</a> type. If the function signature
				4311	indicates the function accepts a variable number of arguments, the extra
				4312	arguments can be specified.</p>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	4313	</li>
Devang Patel	7e9b05e	2008-10-06 18:50:38 +0000	[diff] [blame]	4314	<li>
Devang Patel	0225623	2008-10-07 17:48:33 +0000	[diff] [blame]	4315	<p>The optional <a href="#fnattrs">function attributes</a> list. Only
Devang Patel	7e9b05e	2008-10-06 18:50:38 +0000	[diff] [blame]	4316	'<tt>noreturn</tt>', '<tt>nounwind</tt>', '<tt>readonly</tt>' and
				4317	'<tt>readnone</tt>' attributes are valid here.</p>
				4318	</li>
Chris Lattner	a8292f3	2002-05-06 22:08:29 +0000	[diff] [blame]	4319	</ol>
Chris Lattner	e23c139	2005-05-06 05:47:36 +0000	[diff] [blame]	4320
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	4321	<h5>Semantics:</h5>
Chris Lattner	e23c139	2005-05-06 05:47:36 +0000	[diff] [blame]	4322
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	4323	<p>The '<tt>call</tt>' instruction is used to cause control flow to
				4324	transfer to a specified function, with its incoming arguments bound to
				4325	the specified values. Upon a '<tt><a href="#i_ret">ret</a></tt>'
				4326	instruction in the called function, control flow continues with the
				4327	instruction after the function call, and the return value of the
Dan Gohman	cc3132e	2008-10-04 19:00:07 +0000	[diff] [blame]	4328	function is bound to the result argument.
Chris Lattner	e23c139	2005-05-06 05:47:36 +0000	[diff] [blame]	4329
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	4330	<h5>Example:</h5>
Chris Lattner	e23c139	2005-05-06 05:47:36 +0000	[diff] [blame]	4331
				4332	<pre>
Nick Lewycky	a9b13d5	2007-09-08 13:57:50 +0000	[diff] [blame]	4333	%retval = call i32 @test(i32 %argc)
Chris Lattner	fb7c88d	2008-03-21 17:24:17 +0000	[diff] [blame]	4334	call i32 (i8 , ...) @printf(i8 * %msg, i32 12, i8 42) <i>; yields i32</i>
				4335	%X = tail call i32 @foo() <i>; yields i32</i>
				4336	%Y = tail call <a href="#callingconv">fastcc</a> i32 @foo() <i>; yields i32</i>
				4337	call void %foo(i8 97 signext)
Devang Patel	d6cff51	2008-03-10 20:49:15 +0000	[diff] [blame]	4338
				4339	%struct.A = type { i32, i8 }
Devang Patel	7e9b05e	2008-10-06 18:50:38 +0000	[diff] [blame]	4340	%r = call %struct.A @foo() <i>; yields { 32, i8 }</i>
Dan Gohman	cc3132e	2008-10-04 19:00:07 +0000	[diff] [blame]	4341	%gr = extractvalue %struct.A %r, 0 <i>; yields i32</i>
				4342	%gr1 = extractvalue %struct.A %r, 1 <i>; yields i8</i>
Chris Lattner	6cbe8e9	2008-10-08 06:26:11 +0000	[diff] [blame^]	4343	%Z = call void @foo() noreturn <i>; indicates that %foo never returns normally</i>
Matthijs Kooijman	eefa7df	2008-10-07 10:03:45 +0000	[diff] [blame]	4344	%ZZ = call zeroext i32 @bar() <i>; Return value is %zero extended</i>
Chris Lattner	e23c139	2005-05-06 05:47:36 +0000	[diff] [blame]	4345	</pre>
				4346
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	4347	</div>
Chris Lattner	6a4a049	2004-09-27 21:51:25 +0000	[diff] [blame]	4348
Chris Lattner	bd64b4e	2003-05-08 04:57:36 +0000	[diff] [blame]	4349	<!-- _______________________________________________________________________ -->
Chris Lattner	6a4a049	2004-09-27 21:51:25 +0000	[diff] [blame]	4350	<div class="doc_subsubsection">
Chris Lattner	3333747	2006-01-13 23:26:01 +0000	[diff] [blame]	4351	<a name="i_va_arg">'<tt>va_arg</tt>' Instruction</a>
Chris Lattner	6a4a049	2004-09-27 21:51:25 +0000	[diff] [blame]	4352	</div>
				4353
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	4354	<div class="doc_text">
Chris Lattner	6a4a049	2004-09-27 21:51:25 +0000	[diff] [blame]	4355
Chris Lattner	26ca62e	2003-10-18 05:51:36 +0000	[diff] [blame]	4356	<h5>Syntax:</h5>
Chris Lattner	6a4a049	2004-09-27 21:51:25 +0000	[diff] [blame]	4357
				4358	<pre>
Andrew Lenharth	5fb787c	2005-06-18 18:28:17 +0000	[diff] [blame]	4359	<resultval> = va_arg <va_list*> <arglist>, <argty>
Chris Lattner	6a4a049	2004-09-27 21:51:25 +0000	[diff] [blame]	4360	</pre>
				4361
Chris Lattner	26ca62e	2003-10-18 05:51:36 +0000	[diff] [blame]	4362	<h5>Overview:</h5>
Chris Lattner	6a4a049	2004-09-27 21:51:25 +0000	[diff] [blame]	4363
Andrew Lenharth	5fb787c	2005-06-18 18:28:17 +0000	[diff] [blame]	4364	<p>The '<tt>va_arg</tt>' instruction is used to access arguments passed through
Chris Lattner	6a4a049	2004-09-27 21:51:25 +0000	[diff] [blame]	4365	the "variable argument" area of a function call. It is used to implement the
				4366	<tt>va_arg</tt> macro in C.</p>
				4367
Chris Lattner	26ca62e	2003-10-18 05:51:36 +0000	[diff] [blame]	4368	<h5>Arguments:</h5>
Chris Lattner	6a4a049	2004-09-27 21:51:25 +0000	[diff] [blame]	4369
Andrew Lenharth	5fb787c	2005-06-18 18:28:17 +0000	[diff] [blame]	4370	<p>This instruction takes a <tt>va_list*</tt> value and the type of
				4371	the argument. It returns a value of the specified argument type and
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	4372	increments the <tt>va_list</tt> to point to the next argument. The
Andrew Lenharth	5fb787c	2005-06-18 18:28:17 +0000	[diff] [blame]	4373	actual type of <tt>va_list</tt> is target specific.</p>
Chris Lattner	6a4a049	2004-09-27 21:51:25 +0000	[diff] [blame]	4374
Chris Lattner	26ca62e	2003-10-18 05:51:36 +0000	[diff] [blame]	4375	<h5>Semantics:</h5>
Chris Lattner	6a4a049	2004-09-27 21:51:25 +0000	[diff] [blame]	4376
Andrew Lenharth	5fb787c	2005-06-18 18:28:17 +0000	[diff] [blame]	4377	<p>The '<tt>va_arg</tt>' instruction loads an argument of the specified
				4378	type from the specified <tt>va_list</tt> and causes the
				4379	<tt>va_list</tt> to point to the next argument. For more information,
				4380	see the variable argument handling <a href="#int_varargs">Intrinsic
				4381	Functions</a>.</p>
Chris Lattner	6a4a049	2004-09-27 21:51:25 +0000	[diff] [blame]	4382
				4383	<p>It is legal for this instruction to be called in a function which does not
				4384	take a variable number of arguments, for example, the <tt>vfprintf</tt>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	4385	function.</p>
Chris Lattner	6a4a049	2004-09-27 21:51:25 +0000	[diff] [blame]	4386
Andrew Lenharth	5fb787c	2005-06-18 18:28:17 +0000	[diff] [blame]	4387	<p><tt>va_arg</tt> is an LLVM instruction instead of an <a
John Criswell	8819056	2005-05-16 16:17:45 +0000	[diff] [blame]	4388	href="#intrinsics">intrinsic function</a> because it takes a type as an
Chris Lattner	6a4a049	2004-09-27 21:51:25 +0000	[diff] [blame]	4389	argument.</p>
				4390
Chris Lattner	26ca62e	2003-10-18 05:51:36 +0000	[diff] [blame]	4391	<h5>Example:</h5>
Chris Lattner	6a4a049	2004-09-27 21:51:25 +0000	[diff] [blame]	4392
				4393	<p>See the <a href="#int_varargs">variable argument processing</a> section.</p>
				4394
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	4395	</div>
Chris Lattner	941515c	2004-01-06 05:31:32 +0000	[diff] [blame]	4396
Chris Lattner	bd64b4e	2003-05-08 04:57:36 +0000	[diff] [blame]	4397	<!-- *********************************************************************** -->
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	4398	<div class="doc_section"> <a name="intrinsics">Intrinsic Functions</a> </div>
				4399	<!-- *********************************************************************** -->
Chris Lattner	941515c	2004-01-06 05:31:32 +0000	[diff] [blame]	4400
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	4401	<div class="doc_text">
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	4402
				4403	<p>LLVM supports the notion of an "intrinsic function". These functions have
Reid Spencer	4eefaab	2007-04-01 08:04:23 +0000	[diff] [blame]	4404	well known names and semantics and are required to follow certain restrictions.
				4405	Overall, these intrinsics represent an extension mechanism for the LLVM
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	4406	language that does not require changing all of the transformations in LLVM when
Gabor Greif	a54634a	2007-07-06 22:07:22 +0000	[diff] [blame]	4407	adding to the language (or the bitcode reader/writer, the parser, etc...).</p>
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	4408
John Criswell	8819056	2005-05-16 16:17:45 +0000	[diff] [blame]	4409	<p>Intrinsic function names must all start with an "<tt>llvm.</tt>" prefix. This
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	4410	prefix is reserved in LLVM for intrinsic names; thus, function names may not
				4411	begin with this prefix. Intrinsic functions must always be external functions:
				4412	you cannot define the body of intrinsic functions. Intrinsic functions may
				4413	only be used in call or invoke instructions: it is illegal to take the address
				4414	of an intrinsic function. Additionally, because intrinsic functions are part
				4415	of the LLVM language, it is required if any are added that they be documented
				4416	here.</p>
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	4417
Chandler Carruth	7132e00	2007-08-04 01:51:18 +0000	[diff] [blame]	4418	<p>Some intrinsic functions can be overloaded, i.e., the intrinsic represents
				4419	a family of functions that perform the same operation but on different data
				4420	types. Because LLVM can represent over 8 million different integer types,
				4421	overloading is used commonly to allow an intrinsic function to operate on any
				4422	integer type. One or more of the argument types or the result type can be
				4423	overloaded to accept any integer type. Argument types may also be defined as
				4424	exactly matching a previous argument's type or the result type. This allows an
				4425	intrinsic function which accepts multiple arguments, but needs all of them to
				4426	be of the same type, to only be overloaded with respect to a single argument or
				4427	the result.</p>
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	4428
Chandler Carruth	7132e00	2007-08-04 01:51:18 +0000	[diff] [blame]	4429	<p>Overloaded intrinsics will have the names of its overloaded argument types
				4430	encoded into its function name, each preceded by a period. Only those types
				4431	which are overloaded result in a name suffix. Arguments whose type is matched
				4432	against another type do not. For example, the <tt>llvm.ctpop</tt> function can
				4433	take an integer of any width and returns an integer of exactly the same integer
				4434	width. This leads to a family of functions such as
				4435	<tt>i8 @llvm.ctpop.i8(i8 %val)</tt> and <tt>i29 @llvm.ctpop.i29(i29 %val)</tt>.
				4436	Only one type, the return type, is overloaded, and only one type suffix is
				4437	required. Because the argument's type is matched against the return type, it
				4438	does not require its own name suffix.</p>
Reid Spencer	4eefaab	2007-04-01 08:04:23 +0000	[diff] [blame]	4439
				4440	<p>To learn how to add an intrinsic function, please see the
				4441	<a href="ExtendingLLVM.html">Extending LLVM Guide</a>.
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	4442	</p>
				4443
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	4444	</div>
Chris Lattner	941515c	2004-01-06 05:31:32 +0000	[diff] [blame]	4445
Chris Lattner	bd64b4e	2003-05-08 04:57:36 +0000	[diff] [blame]	4446	<!-- ======================================================================= -->
Chris Lattner	941515c	2004-01-06 05:31:32 +0000	[diff] [blame]	4447	<div class="doc_subsection">
				4448	<a name="int_varargs">Variable Argument Handling Intrinsics</a>
				4449	</div>
				4450
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	4451	<div class="doc_text">
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4452
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	4453	<p>Variable argument support is defined in LLVM with the <a
Chris Lattner	3333747	2006-01-13 23:26:01 +0000	[diff] [blame]	4454	href="#i_va_arg"><tt>va_arg</tt></a> instruction and these three
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	4455	intrinsic functions. These functions are related to the similarly
				4456	named macros defined in the <tt><stdarg.h></tt> header file.</p>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4457
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	4458	<p>All of these functions operate on arguments that use a
				4459	target-specific value type "<tt>va_list</tt>". The LLVM assembly
				4460	language reference manual does not define what this type is, so all
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	4461	transformations should be prepared to handle these functions regardless of
				4462	the type used.</p>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4463
Chris Lattner	30b868d	2006-05-15 17:26:46 +0000	[diff] [blame]	4464	<p>This example shows how the <a href="#i_va_arg"><tt>va_arg</tt></a>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	4465	instruction and the variable argument handling intrinsic functions are
				4466	used.</p>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4467
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	4468	<div class="doc_code">
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	4469	<pre>
Anton Korobeynikov	640bbe0	2007-03-21 23:58:04 +0000	[diff] [blame]	4470	define i32 @test(i32 %X, ...) {
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	4471	; Initialize variable argument processing
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	4472	%ap = alloca i8*
Chris Lattner	db0790c	2007-01-08 07:55:15 +0000	[diff] [blame]	4473	%ap2 = bitcast i8** %ap to i8*
Anton Korobeynikov	640bbe0	2007-03-21 23:58:04 +0000	[diff] [blame]	4474	call void @llvm.va_start(i8* %ap2)
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	4475
				4476	; Read a single integer argument
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	4477	%tmp = va_arg i8** %ap, i32
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	4478
				4479	; Demonstrate usage of llvm.va_copy and llvm.va_end
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	4480	%aq = alloca i8*
Chris Lattner	db0790c	2007-01-08 07:55:15 +0000	[diff] [blame]	4481	%aq2 = bitcast i8** %aq to i8*
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	4482	call void @llvm.va_copy(i8* %aq2, i8* %ap2)
Anton Korobeynikov	640bbe0	2007-03-21 23:58:04 +0000	[diff] [blame]	4483	call void @llvm.va_end(i8* %aq2)
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	4484
				4485	; Stop processing of arguments.
Anton Korobeynikov	640bbe0	2007-03-21 23:58:04 +0000	[diff] [blame]	4486	call void @llvm.va_end(i8* %ap2)
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	4487	ret i32 %tmp
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	4488	}
Anton Korobeynikov	640bbe0	2007-03-21 23:58:04 +0000	[diff] [blame]	4489
				4490	declare void @llvm.va_start(i8*)
				4491	declare void @llvm.va_copy(i8, i8)
				4492	declare void @llvm.va_end(i8*)
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	4493	</pre>
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	4494	</div>
Chris Lattner	941515c	2004-01-06 05:31:32 +0000	[diff] [blame]	4495
Bill Wendling	3716c5d	2007-05-29 09:04:49 +0000	[diff] [blame]	4496	</div>
				4497
Chris Lattner	bd64b4e	2003-05-08 04:57:36 +0000	[diff] [blame]	4498	<!-- _______________________________________________________________________ -->
Chris Lattner	941515c	2004-01-06 05:31:32 +0000	[diff] [blame]	4499	<div class="doc_subsubsection">
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	4500	<a name="int_va_start">'<tt>llvm.va_start</tt>' Intrinsic</a>
Chris Lattner	941515c	2004-01-06 05:31:32 +0000	[diff] [blame]	4501	</div>
				4502
				4503
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	4504	<div class="doc_text">
Chris Lattner	bd64b4e	2003-05-08 04:57:36 +0000	[diff] [blame]	4505	<h5>Syntax:</h5>
Chris Lattner	db0790c	2007-01-08 07:55:15 +0000	[diff] [blame]	4506	<pre> declare void %llvm.va_start(i8* <arglist>)<br></pre>
Chris Lattner	bd64b4e	2003-05-08 04:57:36 +0000	[diff] [blame]	4507	<h5>Overview:</h5>
Andrew Lenharth	5fb787c	2005-06-18 18:28:17 +0000	[diff] [blame]	4508	<P>The '<tt>llvm.va_start</tt>' intrinsic initializes
				4509	<tt>*<arglist></tt> for subsequent use by <tt><a
				4510	href="#i_va_arg">va_arg</a></tt>.</p>
				4511
				4512	<h5>Arguments:</h5>
				4513
				4514	<P>The argument is a pointer to a <tt>va_list</tt> element to initialize.</p>
				4515
Chris Lattner	bd64b4e	2003-05-08 04:57:36 +0000	[diff] [blame]	4516	<h5>Semantics:</h5>
Andrew Lenharth	5fb787c	2005-06-18 18:28:17 +0000	[diff] [blame]	4517
				4518	<P>The '<tt>llvm.va_start</tt>' intrinsic works just like the <tt>va_start</tt>
				4519	macro available in C. In a target-dependent way, it initializes the
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	4520	<tt>va_list</tt> element to which the argument points, so that the next call to
Andrew Lenharth	5fb787c	2005-06-18 18:28:17 +0000	[diff] [blame]	4521	<tt>va_arg</tt> will produce the first variable argument passed to the function.
				4522	Unlike the C <tt>va_start</tt> macro, this intrinsic does not need to know the
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	4523	last argument of the function as the compiler can figure that out.</p>
Andrew Lenharth	5fb787c	2005-06-18 18:28:17 +0000	[diff] [blame]	4524
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	4525	</div>
Chris Lattner	941515c	2004-01-06 05:31:32 +0000	[diff] [blame]	4526
Chris Lattner	bd64b4e	2003-05-08 04:57:36 +0000	[diff] [blame]	4527	<!-- _______________________________________________________________________ -->
Chris Lattner	941515c	2004-01-06 05:31:32 +0000	[diff] [blame]	4528	<div class="doc_subsubsection">
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	4529	<a name="int_va_end">'<tt>llvm.va_end</tt>' Intrinsic</a>
Chris Lattner	941515c	2004-01-06 05:31:32 +0000	[diff] [blame]	4530	</div>
				4531
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	4532	<div class="doc_text">
Chris Lattner	bd64b4e	2003-05-08 04:57:36 +0000	[diff] [blame]	4533	<h5>Syntax:</h5>
Anton Korobeynikov	be9c93c	2007-03-22 00:02:17 +0000	[diff] [blame]	4534	<pre> declare void @llvm.va_end(i8* <arglist>)<br></pre>
Chris Lattner	bd64b4e	2003-05-08 04:57:36 +0000	[diff] [blame]	4535	<h5>Overview:</h5>
Chris Lattner	db0790c	2007-01-08 07:55:15 +0000	[diff] [blame]	4536
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	4537	<p>The '<tt>llvm.va_end</tt>' intrinsic destroys <tt>*<arglist></tt>,
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	4538	which has been initialized previously with <tt><a href="#int_va_start">llvm.va_start</a></tt>
Chris Lattner	48b383b0	2003-11-25 01:02:51 +0000	[diff] [blame]	4539	or <tt><a href="#i_va_copy">llvm.va_copy</a></tt>.</p>
Chris Lattner	db0790c	2007-01-08 07:55:15 +0000	[diff] [blame]	4540
Chris Lattner	bd64b4e	2003-05-08 04:57:36 +0000	[diff] [blame]	4541	<h5>Arguments:</h5>
Chris Lattner	db0790c	2007-01-08 07:55:15 +0000	[diff] [blame]	4542
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	4543	<p>The argument is a pointer to a <tt>va_list</tt> to destroy.</p>
Chris Lattner	db0790c	2007-01-08 07:55:15 +0000	[diff] [blame]	4544
Chris Lattner	bd64b4e	2003-05-08 04:57:36 +0000	[diff] [blame]	4545	<h5>Semantics:</h5>
Chris Lattner	db0790c	2007-01-08 07:55:15 +0000	[diff] [blame]	4546
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	4547	<p>The '<tt>llvm.va_end</tt>' intrinsic works just like the <tt>va_end</tt>
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	4548	macro available in C. In a target-dependent way, it destroys the
				4549	<tt>va_list</tt> element to which the argument points. Calls to <a
				4550	href="#int_va_start"><tt>llvm.va_start</tt></a> and <a href="#int_va_copy">
				4551	<tt>llvm.va_copy</tt></a> must be matched exactly with calls to
				4552	<tt>llvm.va_end</tt>.</p>
Chris Lattner	db0790c	2007-01-08 07:55:15 +0000	[diff] [blame]	4553
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	4554	</div>
Chris Lattner	941515c	2004-01-06 05:31:32 +0000	[diff] [blame]	4555
Chris Lattner	bd64b4e	2003-05-08 04:57:36 +0000	[diff] [blame]	4556	<!-- _______________________________________________________________________ -->
Chris Lattner	941515c	2004-01-06 05:31:32 +0000	[diff] [blame]	4557	<div class="doc_subsubsection">
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	4558	<a name="int_va_copy">'<tt>llvm.va_copy</tt>' Intrinsic</a>
Chris Lattner	941515c	2004-01-06 05:31:32 +0000	[diff] [blame]	4559	</div>
				4560
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	4561	<div class="doc_text">
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4562
Chris Lattner	bd64b4e	2003-05-08 04:57:36 +0000	[diff] [blame]	4563	<h5>Syntax:</h5>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4564
				4565	<pre>
Anton Korobeynikov	be9c93c	2007-03-22 00:02:17 +0000	[diff] [blame]	4566	declare void @llvm.va_copy(i8* <destarglist>, i8* <srcarglist>)
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4567	</pre>
				4568
Chris Lattner	bd64b4e	2003-05-08 04:57:36 +0000	[diff] [blame]	4569	<h5>Overview:</h5>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4570
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	4571	<p>The '<tt>llvm.va_copy</tt>' intrinsic copies the current argument position
				4572	from the source argument list to the destination argument list.</p>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4573
Chris Lattner	bd64b4e	2003-05-08 04:57:36 +0000	[diff] [blame]	4574	<h5>Arguments:</h5>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4575
Andrew Lenharth	5fb787c	2005-06-18 18:28:17 +0000	[diff] [blame]	4576	<p>The first argument is a pointer to a <tt>va_list</tt> element to initialize.
Andrew Lenharth	5305ea5	2005-06-22 20:38:11 +0000	[diff] [blame]	4577	The second argument is a pointer to a <tt>va_list</tt> element to copy from.</p>
Andrew Lenharth	5fb787c	2005-06-18 18:28:17 +0000	[diff] [blame]	4578
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4579
Chris Lattner	bd64b4e	2003-05-08 04:57:36 +0000	[diff] [blame]	4580	<h5>Semantics:</h5>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4581
Jeff Cohen	222a8a4	2007-04-29 01:07:00 +0000	[diff] [blame]	4582	<p>The '<tt>llvm.va_copy</tt>' intrinsic works just like the <tt>va_copy</tt>
				4583	macro available in C. In a target-dependent way, it copies the source
				4584	<tt>va_list</tt> element into the destination <tt>va_list</tt> element. This
				4585	intrinsic is necessary because the <tt><a href="#int_va_start">
				4586	llvm.va_start</a></tt> intrinsic may be arbitrarily complex and require, for
				4587	example, memory allocation.</p>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4588
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	4589	</div>
Chris Lattner	941515c	2004-01-06 05:31:32 +0000	[diff] [blame]	4590
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	4591	<!-- ======================================================================= -->
				4592	<div class="doc_subsection">
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4593	<a name="int_gc">Accurate Garbage Collection Intrinsics</a>
				4594	</div>
				4595
				4596	<div class="doc_text">
				4597
				4598	<p>
				4599	LLVM support for <a href="GarbageCollection.html">Accurate Garbage
Chris Lattner	67c37d1	2008-08-05 18:29:16 +0000	[diff] [blame]	4600	Collection</a> (GC) requires the implementation and generation of these
				4601	intrinsics.
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	4602	These intrinsics allow identification of <a href="#int_gcroot">GC roots on the
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4603	stack</a>, as well as garbage collector implementations that require <a
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	4604	href="#int_gcread">read</a> and <a href="#int_gcwrite">write</a> barriers.
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4605	Front-ends for type-safe garbage collected languages should generate these
				4606	intrinsics to make use of the LLVM garbage collectors. For more details, see <a
				4607	href="GarbageCollection.html">Accurate Garbage Collection with LLVM</a>.
				4608	</p>
Christopher Lamb	55c6d4f	2007-12-17 01:00:21 +0000	[diff] [blame]	4609
				4610	<p>The garbage collection intrinsics only operate on objects in the generic
				4611	address space (address space zero).</p>
				4612
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4613	</div>
				4614
				4615	<!-- _______________________________________________________________________ -->
				4616	<div class="doc_subsubsection">
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	4617	<a name="int_gcroot">'<tt>llvm.gcroot</tt>' Intrinsic</a>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4618	</div>
				4619
				4620	<div class="doc_text">
				4621
				4622	<h5>Syntax:</h5>
				4623
				4624	<pre>
Chris Lattner	1247773	2007-09-21 17:30:40 +0000	[diff] [blame]	4625	declare void @llvm.gcroot(i8** %ptrloc, i8* %metadata)
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4626	</pre>
				4627
				4628	<h5>Overview:</h5>
				4629
John Criswell	dfe6a86	2004-12-10 15:51:16 +0000	[diff] [blame]	4630	<p>The '<tt>llvm.gcroot</tt>' intrinsic declares the existence of a GC root to
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4631	the code generator, and allows some metadata to be associated with it.</p>
				4632
				4633	<h5>Arguments:</h5>
				4634
				4635	<p>The first argument specifies the address of a stack object that contains the
				4636	root pointer. The second pointer (which must be either a constant or a global
				4637	value address) contains the meta-data to be associated with the root.</p>
				4638
				4639	<h5>Semantics:</h5>
				4640
Chris Lattner	851b771	2008-04-24 05:59:56 +0000	[diff] [blame]	4641	<p>At runtime, a call to this intrinsic stores a null pointer into the "ptrloc"
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4642	location. At compile-time, the code generator generates information to allow
Gordon Henriksen	fb56bde	2007-12-25 02:31:26 +0000	[diff] [blame]	4643	the runtime to find the pointer at GC safe points. The '<tt>llvm.gcroot</tt>'
				4644	intrinsic may only be used in a function which <a href="#gc">specifies a GC
				4645	algorithm</a>.</p>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4646
				4647	</div>
				4648
				4649
				4650	<!-- _______________________________________________________________________ -->
				4651	<div class="doc_subsubsection">
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	4652	<a name="int_gcread">'<tt>llvm.gcread</tt>' Intrinsic</a>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4653	</div>
				4654
				4655	<div class="doc_text">
				4656
				4657	<h5>Syntax:</h5>
				4658
				4659	<pre>
Chris Lattner	1247773	2007-09-21 17:30:40 +0000	[diff] [blame]	4660	declare i8* @llvm.gcread(i8* %ObjPtr, i8** %Ptr)
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4661	</pre>
				4662
				4663	<h5>Overview:</h5>
				4664
				4665	<p>The '<tt>llvm.gcread</tt>' intrinsic identifies reads of references from heap
				4666	locations, allowing garbage collector implementations that require read
				4667	barriers.</p>
				4668
				4669	<h5>Arguments:</h5>
				4670
Chris Lattner	f922807	2006-03-14 20:02:51 +0000	[diff] [blame]	4671	<p>The second argument is the address to read from, which should be an address
				4672	allocated from the garbage collector. The first object is a pointer to the
				4673	start of the referenced object, if needed by the language runtime (otherwise
				4674	null).</p>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4675
				4676	<h5>Semantics:</h5>
				4677
				4678	<p>The '<tt>llvm.gcread</tt>' intrinsic has the same semantics as a load
				4679	instruction, but may be replaced with substantially more complex code by the
Gordon Henriksen	fb56bde	2007-12-25 02:31:26 +0000	[diff] [blame]	4680	garbage collector runtime, as needed. The '<tt>llvm.gcread</tt>' intrinsic
				4681	may only be used in a function which <a href="#gc">specifies a GC
				4682	algorithm</a>.</p>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4683
				4684	</div>
				4685
				4686
				4687	<!-- _______________________________________________________________________ -->
				4688	<div class="doc_subsubsection">
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	4689	<a name="int_gcwrite">'<tt>llvm.gcwrite</tt>' Intrinsic</a>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4690	</div>
				4691
				4692	<div class="doc_text">
				4693
				4694	<h5>Syntax:</h5>
				4695
				4696	<pre>
Chris Lattner	1247773	2007-09-21 17:30:40 +0000	[diff] [blame]	4697	declare void @llvm.gcwrite(i8* %P1, i8* %Obj, i8** %P2)
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4698	</pre>
				4699
				4700	<h5>Overview:</h5>
				4701
				4702	<p>The '<tt>llvm.gcwrite</tt>' intrinsic identifies writes of references to heap
				4703	locations, allowing garbage collector implementations that require write
				4704	barriers (such as generational or reference counting collectors).</p>
				4705
				4706	<h5>Arguments:</h5>
				4707
Chris Lattner	f922807	2006-03-14 20:02:51 +0000	[diff] [blame]	4708	<p>The first argument is the reference to store, the second is the start of the
				4709	object to store it to, and the third is the address of the field of Obj to
				4710	store to. If the runtime does not require a pointer to the object, Obj may be
				4711	null.</p>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4712
				4713	<h5>Semantics:</h5>
				4714
				4715	<p>The '<tt>llvm.gcwrite</tt>' intrinsic has the same semantics as a store
				4716	instruction, but may be replaced with substantially more complex code by the
Gordon Henriksen	fb56bde	2007-12-25 02:31:26 +0000	[diff] [blame]	4717	garbage collector runtime, as needed. The '<tt>llvm.gcwrite</tt>' intrinsic
				4718	may only be used in a function which <a href="#gc">specifies a GC
				4719	algorithm</a>.</p>
Chris Lattner	757528b0b	2004-05-23 21:06:01 +0000	[diff] [blame]	4720
				4721	</div>
				4722
				4723
				4724
				4725	<!-- ======================================================================= -->
				4726	<div class="doc_subsection">
Chris Lattner	3649c3a	2004-02-14 04:08:35 +0000	[diff] [blame]	4727	<a name="int_codegen">Code Generator Intrinsics</a>
				4728	</div>
				4729
				4730	<div class="doc_text">
				4731	<p>
				4732	These intrinsics are provided by LLVM to expose special features that may only
				4733	be implemented with code generator support.
				4734	</p>
				4735
				4736	</div>
				4737
				4738	<!-- _______________________________________________________________________ -->
				4739	<div class="doc_subsubsection">
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	4740	<a name="int_returnaddress">'<tt>llvm.returnaddress</tt>' Intrinsic</a>
Chris Lattner	3649c3a	2004-02-14 04:08:35 +0000	[diff] [blame]	4741	</div>
				4742
				4743	<div class="doc_text">
				4744
				4745	<h5>Syntax:</h5>
				4746	<pre>
Anton Korobeynikov	be9c93c	2007-03-22 00:02:17 +0000	[diff] [blame]	4747	declare i8 *@llvm.returnaddress(i32 <level>)
Chris Lattner	3649c3a	2004-02-14 04:08:35 +0000	[diff] [blame]	4748	</pre>
				4749
				4750	<h5>Overview:</h5>
				4751
				4752	<p>
Chris Lattner	c1fb426	2006-10-15 20:05:59 +0000	[diff] [blame]	4753	The '<tt>llvm.returnaddress</tt>' intrinsic attempts to compute a
				4754	target-specific value indicating the return address of the current function
				4755	or one of its callers.
Chris Lattner	3649c3a	2004-02-14 04:08:35 +0000	[diff] [blame]	4756	</p>
				4757
				4758	<h5>Arguments:</h5>
				4759
				4760	<p>
				4761	The argument to this intrinsic indicates which function to return the address
				4762	for. Zero indicates the calling function, one indicates its caller, etc. The
				4763	argument is <b>required</b> to be a constant integer value.
				4764	</p>
				4765
				4766	<h5>Semantics:</h5>
				4767
				4768	<p>
				4769	The '<tt>llvm.returnaddress</tt>' intrinsic either returns a pointer indicating
				4770	the return address of the specified call frame, or zero if it cannot be
				4771	identified. The value returned by this intrinsic is likely to be incorrect or 0
				4772	for arguments other than zero, so it should only be used for debugging purposes.
				4773	</p>
				4774
				4775	<p>
				4776	Note that calling this intrinsic does not prevent function inlining or other
Chris Lattner	2e6eb5f	2005-03-07 20:30:51 +0000	[diff] [blame]	4777	aggressive transformations, so the value returned may not be that of the obvious
Chris Lattner	3649c3a	2004-02-14 04:08:35 +0000	[diff] [blame]	4778	source-language caller.
				4779	</p>
				4780	</div>
				4781
				4782
				4783	<!-- _______________________________________________________________________ -->
				4784	<div class="doc_subsubsection">
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	4785	<a name="int_frameaddress">'<tt>llvm.frameaddress</tt>' Intrinsic</a>
Chris Lattner	3649c3a	2004-02-14 04:08:35 +0000	[diff] [blame]	4786	</div>
				4787
				4788	<div class="doc_text">
				4789
				4790	<h5>Syntax:</h5>
				4791	<pre>
Chris Lattner	1247773	2007-09-21 17:30:40 +0000	[diff] [blame]	4792	declare i8 *@llvm.frameaddress(i32 <level>)
Chris Lattner	3649c3a	2004-02-14 04:08:35 +0000	[diff] [blame]	4793	</pre>
				4794
				4795	<h5>Overview:</h5>
				4796
				4797	<p>
Chris Lattner	c1fb426	2006-10-15 20:05:59 +0000	[diff] [blame]	4798	The '<tt>llvm.frameaddress</tt>' intrinsic attempts to return the
				4799	target-specific frame pointer value for the specified stack frame.
Chris Lattner	3649c3a	2004-02-14 04:08:35 +0000	[diff] [blame]	4800	</p>
				4801
				4802	<h5>Arguments:</h5>
				4803
				4804	<p>
				4805	The argument to this intrinsic indicates which function to return the frame
				4806	pointer for. Zero indicates the calling function, one indicates its caller,
				4807	etc. The argument is <b>required</b> to be a constant integer value.
				4808	</p>
				4809
				4810	<h5>Semantics:</h5>
				4811
				4812	<p>
				4813	The '<tt>llvm.frameaddress</tt>' intrinsic either returns a pointer indicating
				4814	the frame address of the specified call frame, or zero if it cannot be
				4815	identified. The value returned by this intrinsic is likely to be incorrect or 0
				4816	for arguments other than zero, so it should only be used for debugging purposes.
				4817	</p>
				4818
				4819	<p>
				4820	Note that calling this intrinsic does not prevent function inlining or other
Chris Lattner	2e6eb5f	2005-03-07 20:30:51 +0000	[diff] [blame]	4821	aggressive transformations, so the value returned may not be that of the obvious
Chris Lattner	3649c3a	2004-02-14 04:08:35 +0000	[diff] [blame]	4822	source-language caller.
				4823	</p>
				4824	</div>
				4825
Chris Lattner	c8a2c22	2005-02-28 19:24:19 +0000	[diff] [blame]	4826	<!-- _______________________________________________________________________ -->
				4827	<div class="doc_subsubsection">
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	4828	<a name="int_stacksave">'<tt>llvm.stacksave</tt>' Intrinsic</a>
Chris Lattner	2f0f001	2006-01-13 02:03:13 +0000	[diff] [blame]	4829	</div>
				4830
				4831	<div class="doc_text">
				4832
				4833	<h5>Syntax:</h5>
				4834	<pre>
Chris Lattner	1247773	2007-09-21 17:30:40 +0000	[diff] [blame]	4835	declare i8 *@llvm.stacksave()
Chris Lattner	2f0f001	2006-01-13 02:03:13 +0000	[diff] [blame]	4836	</pre>
				4837
				4838	<h5>Overview:</h5>
				4839
				4840	<p>
				4841	The '<tt>llvm.stacksave</tt>' intrinsic is used to remember the current state of
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	4842	the function stack, for use with <a href="#int_stackrestore">
Chris Lattner	2f0f001	2006-01-13 02:03:13 +0000	[diff] [blame]	4843	<tt>llvm.stackrestore</tt></a>. This is useful for implementing language
				4844	features like scoped automatic variable sized arrays in C99.
				4845	</p>
				4846
				4847	<h5>Semantics:</h5>
				4848
				4849	<p>
				4850	This intrinsic returns a opaque pointer value that can be passed to <a
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	4851	href="#int_stackrestore"><tt>llvm.stackrestore</tt></a>. When an
Chris Lattner	2f0f001	2006-01-13 02:03:13 +0000	[diff] [blame]	4852	<tt>llvm.stackrestore</tt> intrinsic is executed with a value saved from
				4853	<tt>llvm.stacksave</tt>, it effectively restores the state of the stack to the
				4854	state it was in when the <tt>llvm.stacksave</tt> intrinsic executed. In
				4855	practice, this pops any <a href="#i_alloca">alloca</a> blocks from the stack
				4856	that were allocated after the <tt>llvm.stacksave</tt> was executed.
				4857	</p>
				4858
				4859	</div>
				4860
				4861	<!-- _______________________________________________________________________ -->
				4862	<div class="doc_subsubsection">
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	4863	<a name="int_stackrestore">'<tt>llvm.stackrestore</tt>' Intrinsic</a>
Chris Lattner	2f0f001	2006-01-13 02:03:13 +0000	[diff] [blame]	4864	</div>
				4865
				4866	<div class="doc_text">
				4867
				4868	<h5>Syntax:</h5>
				4869	<pre>
Anton Korobeynikov	be9c93c	2007-03-22 00:02:17 +0000	[diff] [blame]	4870	declare void @llvm.stackrestore(i8 * %ptr)
Chris Lattner	2f0f001	2006-01-13 02:03:13 +0000	[diff] [blame]	4871	</pre>
				4872
				4873	<h5>Overview:</h5>
				4874
				4875	<p>
				4876	The '<tt>llvm.stackrestore</tt>' intrinsic is used to restore the state of
				4877	the function stack to the state it was in when the corresponding <a
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	4878	href="#int_stacksave"><tt>llvm.stacksave</tt></a> intrinsic executed. This is
Chris Lattner	2f0f001	2006-01-13 02:03:13 +0000	[diff] [blame]	4879	useful for implementing language features like scoped automatic variable sized
				4880	arrays in C99.
				4881	</p>
				4882
				4883	<h5>Semantics:</h5>
				4884
				4885	<p>
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	4886	See the description for <a href="#int_stacksave"><tt>llvm.stacksave</tt></a>.
Chris Lattner	2f0f001	2006-01-13 02:03:13 +0000	[diff] [blame]	4887	</p>
				4888
				4889	</div>
				4890
				4891
				4892	<!-- _______________________________________________________________________ -->
				4893	<div class="doc_subsubsection">
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	4894	<a name="int_prefetch">'<tt>llvm.prefetch</tt>' Intrinsic</a>
Chris Lattner	c8a2c22	2005-02-28 19:24:19 +0000	[diff] [blame]	4895	</div>
				4896
				4897	<div class="doc_text">
				4898
				4899	<h5>Syntax:</h5>
				4900	<pre>
Chris Lattner	1247773	2007-09-21 17:30:40 +0000	[diff] [blame]	4901	declare void @llvm.prefetch(i8* <address>, i32 <rw>, i32 <locality>)
Chris Lattner	c8a2c22	2005-02-28 19:24:19 +0000	[diff] [blame]	4902	</pre>
				4903
				4904	<h5>Overview:</h5>
				4905
				4906
				4907	<p>
				4908	The '<tt>llvm.prefetch</tt>' intrinsic is a hint to the code generator to insert
John Criswell	8819056	2005-05-16 16:17:45 +0000	[diff] [blame]	4909	a prefetch instruction if supported; otherwise, it is a noop. Prefetches have
				4910	no
				4911	effect on the behavior of the program but can change its performance
Chris Lattner	ff85107	2005-02-28 19:47:14 +0000	[diff] [blame]	4912	characteristics.
Chris Lattner	c8a2c22	2005-02-28 19:24:19 +0000	[diff] [blame]	4913	</p>
				4914
				4915	<h5>Arguments:</h5>
				4916
				4917	<p>
				4918	<tt>address</tt> is the address to be prefetched, <tt>rw</tt> is the specifier
				4919	determining if the fetch should be for a read (0) or write (1), and
				4920	<tt>locality</tt> is a temporal locality specifier ranging from (0) - no
Chris Lattner	d3e641c	2005-03-07 20:31:38 +0000	[diff] [blame]	4921	locality, to (3) - extremely local keep in cache. The <tt>rw</tt> and
Chris Lattner	c8a2c22	2005-02-28 19:24:19 +0000	[diff] [blame]	4922	<tt>locality</tt> arguments must be constant integers.
				4923	</p>
				4924
				4925	<h5>Semantics:</h5>
				4926
				4927	<p>
				4928	This intrinsic does not modify the behavior of the program. In particular,
				4929	prefetches cannot trap and do not produce a value. On targets that support this
				4930	intrinsic, the prefetch can provide hints to the processor cache for better
				4931	performance.
				4932	</p>
				4933
				4934	</div>
				4935
Andrew Lenharth	b442791	2005-03-28 20:05:49 +0000	[diff] [blame]	4936	<!-- _______________________________________________________________________ -->
				4937	<div class="doc_subsubsection">
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	4938	<a name="int_pcmarker">'<tt>llvm.pcmarker</tt>' Intrinsic</a>
Andrew Lenharth	b442791	2005-03-28 20:05:49 +0000	[diff] [blame]	4939	</div>
				4940
				4941	<div class="doc_text">
				4942
				4943	<h5>Syntax:</h5>
				4944	<pre>
Chris Lattner	1247773	2007-09-21 17:30:40 +0000	[diff] [blame]	4945	declare void @llvm.pcmarker(i32 <id>)
Andrew Lenharth	b442791	2005-03-28 20:05:49 +0000	[diff] [blame]	4946	</pre>
				4947
				4948	<h5>Overview:</h5>
				4949
				4950
				4951	<p>
John Criswell	8819056	2005-05-16 16:17:45 +0000	[diff] [blame]	4952	The '<tt>llvm.pcmarker</tt>' intrinsic is a method to export a Program Counter
Chris Lattner	67c37d1	2008-08-05 18:29:16 +0000	[diff] [blame]	4953	(PC) in a region of
				4954	code to simulators and other tools. The method is target specific, but it is
				4955	expected that the marker will use exported symbols to transmit the PC of the
				4956	marker.
				4957	The marker makes no guarantees that it will remain with any specific instruction
				4958	after optimizations. It is possible that the presence of a marker will inhibit
Chris Lattner	b40261e	2006-03-24 07:16:10 +0000	[diff] [blame]	4959	optimizations. The intended use is to be inserted after optimizations to allow
John Criswell	8819056	2005-05-16 16:17:45 +0000	[diff] [blame]	4960	correlations of simulation runs.
Andrew Lenharth	b442791	2005-03-28 20:05:49 +0000	[diff] [blame]	4961	</p>
				4962
				4963	<h5>Arguments:</h5>
				4964
				4965	<p>
				4966	<tt>id</tt> is a numerical id identifying the marker.
				4967	</p>
				4968
				4969	<h5>Semantics:</h5>
				4970
				4971	<p>
				4972	This intrinsic does not modify the behavior of the program. Backends that do not
				4973	support this intrinisic may ignore it.
				4974	</p>
				4975
				4976	</div>
				4977
Andrew Lenharth	01aa563	2005-11-11 16:47:30 +0000	[diff] [blame]	4978	<!-- _______________________________________________________________________ -->
				4979	<div class="doc_subsubsection">
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	4980	<a name="int_readcyclecounter">'<tt>llvm.readcyclecounter</tt>' Intrinsic</a>
Andrew Lenharth	01aa563	2005-11-11 16:47:30 +0000	[diff] [blame]	4981	</div>
				4982
				4983	<div class="doc_text">
				4984
				4985	<h5>Syntax:</h5>
				4986	<pre>
Anton Korobeynikov	be9c93c	2007-03-22 00:02:17 +0000	[diff] [blame]	4987	declare i64 @llvm.readcyclecounter( )
Andrew Lenharth	01aa563	2005-11-11 16:47:30 +0000	[diff] [blame]	4988	</pre>
				4989
				4990	<h5>Overview:</h5>
				4991
				4992
				4993	<p>
				4994	The '<tt>llvm.readcyclecounter</tt>' intrinsic provides access to the cycle
				4995	counter register (or similar low latency, high accuracy clocks) on those targets
				4996	that support it. On X86, it should map to RDTSC. On Alpha, it should map to RPCC.
				4997	As the backing counters overflow quickly (on the order of 9 seconds on alpha), this
				4998	should only be used for small timings.
				4999	</p>
				5000
				5001	<h5>Semantics:</h5>
				5002
				5003	<p>
				5004	When directly supported, reading the cycle counter should not modify any memory.
				5005	Implementations are allowed to either return a application specific value or a
				5006	system wide value. On backends without support, this is lowered to a constant 0.
				5007	</p>
				5008
				5009	</div>
				5010
Chris Lattner	3649c3a	2004-02-14 04:08:35 +0000	[diff] [blame]	5011	<!-- ======================================================================= -->
				5012	<div class="doc_subsection">
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	5013	<a name="int_libc">Standard C Library Intrinsics</a>
				5014	</div>
				5015
				5016	<div class="doc_text">
				5017	<p>
Chris Lattner	3649c3a	2004-02-14 04:08:35 +0000	[diff] [blame]	5018	LLVM provides intrinsics for a few important standard C library functions.
				5019	These intrinsics allow source-language front-ends to pass information about the
				5020	alignment of the pointer arguments to the code generator, providing opportunity
				5021	for more efficient code generation.
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	5022	</p>
				5023
				5024	</div>
				5025
				5026	<!-- _______________________________________________________________________ -->
				5027	<div class="doc_subsubsection">
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	5028	<a name="int_memcpy">'<tt>llvm.memcpy</tt>' Intrinsic</a>
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	5029	</div>
				5030
				5031	<div class="doc_text">
				5032
				5033	<h5>Syntax:</h5>
				5034	<pre>
Anton Korobeynikov	be9c93c	2007-03-22 00:02:17 +0000	[diff] [blame]	5035	declare void @llvm.memcpy.i32(i8 * <dest>, i8 * <src>,
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	5036	i32 <len>, i32 <align>)
Anton Korobeynikov	be9c93c	2007-03-22 00:02:17 +0000	[diff] [blame]	5037	declare void @llvm.memcpy.i64(i8 * <dest>, i8 * <src>,
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	5038	i64 <len>, i32 <align>)
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	5039	</pre>
				5040
				5041	<h5>Overview:</h5>
				5042
				5043	<p>
Chris Lattner	0c8b259	2006-03-03 00:07:20 +0000	[diff] [blame]	5044	The '<tt>llvm.memcpy.*</tt>' intrinsics copy a block of memory from the source
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	5045	location to the destination location.
				5046	</p>
				5047
				5048	<p>
Chris Lattner	0c8b259	2006-03-03 00:07:20 +0000	[diff] [blame]	5049	Note that, unlike the standard libc function, the <tt>llvm.memcpy.*</tt>
				5050	intrinsics do not return a value, and takes an extra alignment argument.
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	5051	</p>
				5052
				5053	<h5>Arguments:</h5>
				5054
				5055	<p>
				5056	The first argument is a pointer to the destination, the second is a pointer to
Chris Lattner	0c8b259	2006-03-03 00:07:20 +0000	[diff] [blame]	5057	the source. The third argument is an integer argument
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	5058	specifying the number of bytes to copy, and the fourth argument is the alignment
				5059	of the source and destination locations.
				5060	</p>
				5061
Chris Lattner	4c67c48	2004-02-12 21:18:15 +0000	[diff] [blame]	5062	<p>
				5063	If the call to this intrinisic has an alignment value that is not 0 or 1, then
Chris Lattner	5316e5d	2006-03-04 00:02:10 +0000	[diff] [blame]	5064	the caller guarantees that both the source and destination pointers are aligned
				5065	to that boundary.
Chris Lattner	4c67c48	2004-02-12 21:18:15 +0000	[diff] [blame]	5066	</p>
				5067
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	5068	<h5>Semantics:</h5>
				5069
				5070	<p>
Chris Lattner	0c8b259	2006-03-03 00:07:20 +0000	[diff] [blame]	5071	The '<tt>llvm.memcpy.*</tt>' intrinsics copy a block of memory from the source
Chris Lattner	fee1146	2004-02-12 17:01:32 +0000	[diff] [blame]	5072	location to the destination location, which are not allowed to overlap. It
				5073	copies "len" bytes of memory over. If the argument is known to be aligned to
				5074	some boundary, this can be specified as the fourth argument, otherwise it should
				5075	be set to 0 or 1.
				5076	</p>
				5077	</div>
				5078
				5079
Chris Lattner	f30152e	2004-02-12 18:10:10 +0000	[diff] [blame]	5080	<!-- _______________________________________________________________________ -->
				5081	<div class="doc_subsubsection">
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	5082	<a name="int_memmove">'<tt>llvm.memmove</tt>' Intrinsic</a>
Chris Lattner	f30152e	2004-02-12 18:10:10 +0000	[diff] [blame]	5083	</div>
				5084
				5085	<div class="doc_text">
				5086
				5087	<h5>Syntax:</h5>
				5088	<pre>
Anton Korobeynikov	be9c93c	2007-03-22 00:02:17 +0000	[diff] [blame]	5089	declare void @llvm.memmove.i32(i8 * <dest>, i8 * <src>,
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	5090	i32 <len>, i32 <align>)
Anton Korobeynikov	be9c93c	2007-03-22 00:02:17 +0000	[diff] [blame]	5091	declare void @llvm.memmove.i64(i8 * <dest>, i8 * <src>,
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	5092	i64 <len>, i32 <align>)
Chris Lattner	f30152e	2004-02-12 18:10:10 +0000	[diff] [blame]	5093	</pre>
				5094
				5095	<h5>Overview:</h5>
				5096
				5097	<p>
Chris Lattner	0c8b259	2006-03-03 00:07:20 +0000	[diff] [blame]	5098	The '<tt>llvm.memmove.*</tt>' intrinsics move a block of memory from the source
				5099	location to the destination location. It is similar to the
Chris Lattner	ec56402	2008-01-06 19:51:52 +0000	[diff] [blame]	5100	'<tt>llvm.memcpy</tt>' intrinsic but allows the two memory locations to overlap.
Chris Lattner	f30152e	2004-02-12 18:10:10 +0000	[diff] [blame]	5101	</p>
				5102
				5103	<p>
Chris Lattner	0c8b259	2006-03-03 00:07:20 +0000	[diff] [blame]	5104	Note that, unlike the standard libc function, the <tt>llvm.memmove.*</tt>
				5105	intrinsics do not return a value, and takes an extra alignment argument.
Chris Lattner	f30152e	2004-02-12 18:10:10 +0000	[diff] [blame]	5106	</p>
				5107
				5108	<h5>Arguments:</h5>
				5109
				5110	<p>
				5111	The first argument is a pointer to the destination, the second is a pointer to
Chris Lattner	0c8b259	2006-03-03 00:07:20 +0000	[diff] [blame]	5112	the source. The third argument is an integer argument
Chris Lattner	f30152e	2004-02-12 18:10:10 +0000	[diff] [blame]	5113	specifying the number of bytes to copy, and the fourth argument is the alignment
				5114	of the source and destination locations.
				5115	</p>
				5116
Chris Lattner	4c67c48	2004-02-12 21:18:15 +0000	[diff] [blame]	5117	<p>
				5118	If the call to this intrinisic has an alignment value that is not 0 or 1, then
Chris Lattner	5316e5d	2006-03-04 00:02:10 +0000	[diff] [blame]	5119	the caller guarantees that the source and destination pointers are aligned to
				5120	that boundary.
Chris Lattner	4c67c48	2004-02-12 21:18:15 +0000	[diff] [blame]	5121	</p>
				5122
Chris Lattner	f30152e	2004-02-12 18:10:10 +0000	[diff] [blame]	5123	<h5>Semantics:</h5>
				5124
				5125	<p>
Chris Lattner	0c8b259	2006-03-03 00:07:20 +0000	[diff] [blame]	5126	The '<tt>llvm.memmove.*</tt>' intrinsics copy a block of memory from the source
Chris Lattner	f30152e	2004-02-12 18:10:10 +0000	[diff] [blame]	5127	location to the destination location, which may overlap. It
				5128	copies "len" bytes of memory over. If the argument is known to be aligned to
				5129	some boundary, this can be specified as the fourth argument, otherwise it should
				5130	be set to 0 or 1.
				5131	</p>
				5132	</div>
				5133
Chris Lattner	941515c	2004-01-06 05:31:32 +0000	[diff] [blame]	5134
Chris Lattner	3649c3a	2004-02-14 04:08:35 +0000	[diff] [blame]	5135	<!-- _______________________________________________________________________ -->
				5136	<div class="doc_subsubsection">
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	5137	<a name="int_memset">'<tt>llvm.memset.*</tt>' Intrinsics</a>
Chris Lattner	3649c3a	2004-02-14 04:08:35 +0000	[diff] [blame]	5138	</div>
				5139
				5140	<div class="doc_text">
				5141
				5142	<h5>Syntax:</h5>
				5143	<pre>
Anton Korobeynikov	be9c93c	2007-03-22 00:02:17 +0000	[diff] [blame]	5144	declare void @llvm.memset.i32(i8 * <dest>, i8 <val>,
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	5145	i32 <len>, i32 <align>)
Anton Korobeynikov	be9c93c	2007-03-22 00:02:17 +0000	[diff] [blame]	5146	declare void @llvm.memset.i64(i8 * <dest>, i8 <val>,
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	5147	i64 <len>, i32 <align>)
Chris Lattner	3649c3a	2004-02-14 04:08:35 +0000	[diff] [blame]	5148	</pre>
				5149
				5150	<h5>Overview:</h5>
				5151
				5152	<p>
Chris Lattner	0c8b259	2006-03-03 00:07:20 +0000	[diff] [blame]	5153	The '<tt>llvm.memset.*</tt>' intrinsics fill a block of memory with a particular
Chris Lattner	3649c3a	2004-02-14 04:08:35 +0000	[diff] [blame]	5154	byte value.
				5155	</p>
				5156
				5157	<p>
				5158	Note that, unlike the standard libc function, the <tt>llvm.memset</tt> intrinsic
				5159	does not return a value, and takes an extra alignment argument.
				5160	</p>
				5161
				5162	<h5>Arguments:</h5>
				5163
				5164	<p>
				5165	The first argument is a pointer to the destination to fill, the second is the
Chris Lattner	0c8b259	2006-03-03 00:07:20 +0000	[diff] [blame]	5166	byte value to fill it with, the third argument is an integer
Chris Lattner	3649c3a	2004-02-14 04:08:35 +0000	[diff] [blame]	5167	argument specifying the number of bytes to fill, and the fourth argument is the
				5168	known alignment of destination location.
				5169	</p>
				5170
				5171	<p>
				5172	If the call to this intrinisic has an alignment value that is not 0 or 1, then
Chris Lattner	5316e5d	2006-03-04 00:02:10 +0000	[diff] [blame]	5173	the caller guarantees that the destination pointer is aligned to that boundary.
Chris Lattner	3649c3a	2004-02-14 04:08:35 +0000	[diff] [blame]	5174	</p>
				5175
				5176	<h5>Semantics:</h5>
				5177
				5178	<p>
Chris Lattner	0c8b259	2006-03-03 00:07:20 +0000	[diff] [blame]	5179	The '<tt>llvm.memset.*</tt>' intrinsics fill "len" bytes of memory starting at
				5180	the
Chris Lattner	3649c3a	2004-02-14 04:08:35 +0000	[diff] [blame]	5181	destination location. If the argument is known to be aligned to some boundary,
				5182	this can be specified as the fourth argument, otherwise it should be set to 0 or
				5183	1.
				5184	</p>
				5185	</div>
				5186
				5187
Chris Lattner	3b4f437	2004-06-11 02:28:03 +0000	[diff] [blame]	5188	<!-- _______________________________________________________________________ -->
				5189	<div class="doc_subsubsection">
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	5190	<a name="int_sqrt">'<tt>llvm.sqrt.*</tt>' Intrinsic</a>
Chris Lattner	8a8f2e5	2005-07-21 01:29:16 +0000	[diff] [blame]	5191	</div>
				5192
				5193	<div class="doc_text">
				5194
				5195	<h5>Syntax:</h5>
Dale Johannesen	dd89d27	2007-10-02 17:47:38 +0000	[diff] [blame]	5196	<p>This is an overloaded intrinsic. You can use <tt>llvm.sqrt</tt> on any
Dan Gohman	b6324c1	2007-10-15 20:30:11 +0000	[diff] [blame]	5197	floating point or vector of floating point type. Not all targets support all
				5198	types however.
Chris Lattner	8a8f2e5	2005-07-21 01:29:16 +0000	[diff] [blame]	5199	<pre>
Dale Johannesen	dd89d27	2007-10-02 17:47:38 +0000	[diff] [blame]	5200	declare float @llvm.sqrt.f32(float %Val)
				5201	declare double @llvm.sqrt.f64(double %Val)
				5202	declare x86_fp80 @llvm.sqrt.f80(x86_fp80 %Val)
				5203	declare fp128 @llvm.sqrt.f128(fp128 %Val)
				5204	declare ppc_fp128 @llvm.sqrt.ppcf128(ppc_fp128 %Val)
Chris Lattner	8a8f2e5	2005-07-21 01:29:16 +0000	[diff] [blame]	5205	</pre>
				5206
				5207	<h5>Overview:</h5>
				5208
				5209	<p>
Reid Spencer	b4f9a6f	2006-01-16 21:12:35 +0000	[diff] [blame]	5210	The '<tt>llvm.sqrt</tt>' intrinsics return the sqrt of the specified operand,
Dan Gohman	b6324c1	2007-10-15 20:30:11 +0000	[diff] [blame]	5211	returning the same value as the libm '<tt>sqrt</tt>' functions would. Unlike
Chris Lattner	8a8f2e5	2005-07-21 01:29:16 +0000	[diff] [blame]	5212	<tt>sqrt</tt> in libm, however, <tt>llvm.sqrt</tt> has undefined behavior for
Chris Lattner	00d7cb9	2008-01-29 07:00:44 +0000	[diff] [blame]	5213	negative numbers other than -0.0 (which allows for better optimization, because
				5214	there is no need to worry about errno being set). <tt>llvm.sqrt(-0.0)</tt> is
				5215	defined to return -0.0 like IEEE sqrt.
Chris Lattner	8a8f2e5	2005-07-21 01:29:16 +0000	[diff] [blame]	5216	</p>
				5217
				5218	<h5>Arguments:</h5>
				5219
				5220	<p>
				5221	The argument and return value are floating point numbers of the same type.
				5222	</p>
				5223
				5224	<h5>Semantics:</h5>
				5225
				5226	<p>
Dan Gohman	33988db	2007-07-16 14:37:41 +0000	[diff] [blame]	5227	This function returns the sqrt of the specified operand if it is a nonnegative
Chris Lattner	8a8f2e5	2005-07-21 01:29:16 +0000	[diff] [blame]	5228	floating point number.
				5229	</p>
				5230	</div>
				5231
Chris Lattner	33b73f9	2006-09-08 06:34:02 +0000	[diff] [blame]	5232	<!-- _______________________________________________________________________ -->
				5233	<div class="doc_subsubsection">
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	5234	<a name="int_powi">'<tt>llvm.powi.*</tt>' Intrinsic</a>
Chris Lattner	33b73f9	2006-09-08 06:34:02 +0000	[diff] [blame]	5235	</div>
				5236
				5237	<div class="doc_text">
				5238
				5239	<h5>Syntax:</h5>
Dale Johannesen	dd89d27	2007-10-02 17:47:38 +0000	[diff] [blame]	5240	<p>This is an overloaded intrinsic. You can use <tt>llvm.powi</tt> on any
Dan Gohman	b6324c1	2007-10-15 20:30:11 +0000	[diff] [blame]	5241	floating point or vector of floating point type. Not all targets support all
				5242	types however.
Chris Lattner	33b73f9	2006-09-08 06:34:02 +0000	[diff] [blame]	5243	<pre>
Dale Johannesen	dd89d27	2007-10-02 17:47:38 +0000	[diff] [blame]	5244	declare float @llvm.powi.f32(float %Val, i32 %power)
				5245	declare double @llvm.powi.f64(double %Val, i32 %power)
				5246	declare x86_fp80 @llvm.powi.f80(x86_fp80 %Val, i32 %power)
				5247	declare fp128 @llvm.powi.f128(fp128 %Val, i32 %power)
				5248	declare ppc_fp128 @llvm.powi.ppcf128(ppc_fp128 %Val, i32 %power)
Chris Lattner	33b73f9	2006-09-08 06:34:02 +0000	[diff] [blame]	5249	</pre>
				5250
				5251	<h5>Overview:</h5>
				5252
				5253	<p>
				5254	The '<tt>llvm.powi.*</tt>' intrinsics return the first operand raised to the
				5255	specified (positive or negative) power. The order of evaluation of
Dan Gohman	b6324c1	2007-10-15 20:30:11 +0000	[diff] [blame]	5256	multiplications is not defined. When a vector of floating point type is
				5257	used, the second argument remains a scalar integer value.
Chris Lattner	33b73f9	2006-09-08 06:34:02 +0000	[diff] [blame]	5258	</p>
				5259
				5260	<h5>Arguments:</h5>
				5261
				5262	<p>
				5263	The second argument is an integer power, and the first is a value to raise to
				5264	that power.
				5265	</p>
				5266
				5267	<h5>Semantics:</h5>
				5268
				5269	<p>
				5270	This function returns the first value raised to the second power with an
				5271	unspecified sequence of rounding operations.</p>
				5272	</div>
				5273
Dan Gohman	b6324c1	2007-10-15 20:30:11 +0000	[diff] [blame]	5274	<!-- _______________________________________________________________________ -->
				5275	<div class="doc_subsubsection">
				5276	<a name="int_sin">'<tt>llvm.sin.*</tt>' Intrinsic</a>
				5277	</div>
				5278
				5279	<div class="doc_text">
				5280
				5281	<h5>Syntax:</h5>
				5282	<p>This is an overloaded intrinsic. You can use <tt>llvm.sin</tt> on any
				5283	floating point or vector of floating point type. Not all targets support all
				5284	types however.
				5285	<pre>
				5286	declare float @llvm.sin.f32(float %Val)
				5287	declare double @llvm.sin.f64(double %Val)
				5288	declare x86_fp80 @llvm.sin.f80(x86_fp80 %Val)
				5289	declare fp128 @llvm.sin.f128(fp128 %Val)
				5290	declare ppc_fp128 @llvm.sin.ppcf128(ppc_fp128 %Val)
				5291	</pre>
				5292
				5293	<h5>Overview:</h5>
				5294
				5295	<p>
				5296	The '<tt>llvm.sin.*</tt>' intrinsics return the sine of the operand.
				5297	</p>
				5298
				5299	<h5>Arguments:</h5>
				5300
				5301	<p>
				5302	The argument and return value are floating point numbers of the same type.
				5303	</p>
				5304
				5305	<h5>Semantics:</h5>
				5306
				5307	<p>
				5308	This function returns the sine of the specified operand, returning the
				5309	same values as the libm <tt>sin</tt> functions would, and handles error
Dan Gohman	d0806a0	2007-10-17 18:05:13 +0000	[diff] [blame]	5310	conditions in the same way.</p>
Dan Gohman	b6324c1	2007-10-15 20:30:11 +0000	[diff] [blame]	5311	</div>
				5312
				5313	<!-- _______________________________________________________________________ -->
				5314	<div class="doc_subsubsection">
				5315	<a name="int_cos">'<tt>llvm.cos.*</tt>' Intrinsic</a>
				5316	</div>
				5317
				5318	<div class="doc_text">
				5319
				5320	<h5>Syntax:</h5>
				5321	<p>This is an overloaded intrinsic. You can use <tt>llvm.cos</tt> on any
				5322	floating point or vector of floating point type. Not all targets support all
				5323	types however.
				5324	<pre>
				5325	declare float @llvm.cos.f32(float %Val)
				5326	declare double @llvm.cos.f64(double %Val)
				5327	declare x86_fp80 @llvm.cos.f80(x86_fp80 %Val)
				5328	declare fp128 @llvm.cos.f128(fp128 %Val)
				5329	declare ppc_fp128 @llvm.cos.ppcf128(ppc_fp128 %Val)
				5330	</pre>
				5331
				5332	<h5>Overview:</h5>
				5333
				5334	<p>
				5335	The '<tt>llvm.cos.*</tt>' intrinsics return the cosine of the operand.
				5336	</p>
				5337
				5338	<h5>Arguments:</h5>
				5339
				5340	<p>
				5341	The argument and return value are floating point numbers of the same type.
				5342	</p>
				5343
				5344	<h5>Semantics:</h5>
				5345
				5346	<p>
				5347	This function returns the cosine of the specified operand, returning the
				5348	same values as the libm <tt>cos</tt> functions would, and handles error
Dan Gohman	d0806a0	2007-10-17 18:05:13 +0000	[diff] [blame]	5349	conditions in the same way.</p>
Dan Gohman	b6324c1	2007-10-15 20:30:11 +0000	[diff] [blame]	5350	</div>
				5351
				5352	<!-- _______________________________________________________________________ -->
				5353	<div class="doc_subsubsection">
				5354	<a name="int_pow">'<tt>llvm.pow.*</tt>' Intrinsic</a>
				5355	</div>
				5356
				5357	<div class="doc_text">
				5358
				5359	<h5>Syntax:</h5>
				5360	<p>This is an overloaded intrinsic. You can use <tt>llvm.pow</tt> on any
				5361	floating point or vector of floating point type. Not all targets support all
				5362	types however.
				5363	<pre>
				5364	declare float @llvm.pow.f32(float %Val, float %Power)
				5365	declare double @llvm.pow.f64(double %Val, double %Power)
				5366	declare x86_fp80 @llvm.pow.f80(x86_fp80 %Val, x86_fp80 %Power)
				5367	declare fp128 @llvm.pow.f128(fp128 %Val, fp128 %Power)
				5368	declare ppc_fp128 @llvm.pow.ppcf128(ppc_fp128 %Val, ppc_fp128 Power)
				5369	</pre>
				5370
				5371	<h5>Overview:</h5>
				5372
				5373	<p>
				5374	The '<tt>llvm.pow.*</tt>' intrinsics return the first operand raised to the
				5375	specified (positive or negative) power.
				5376	</p>
				5377
				5378	<h5>Arguments:</h5>
				5379
				5380	<p>
				5381	The second argument is a floating point power, and the first is a value to
				5382	raise to that power.
				5383	</p>
				5384
				5385	<h5>Semantics:</h5>
				5386
				5387	<p>
				5388	This function returns the first value raised to the second power,
				5389	returning the
				5390	same values as the libm <tt>pow</tt> functions would, and handles error
Dan Gohman	d0806a0	2007-10-17 18:05:13 +0000	[diff] [blame]	5391	conditions in the same way.</p>
Dan Gohman	b6324c1	2007-10-15 20:30:11 +0000	[diff] [blame]	5392	</div>
				5393
Chris Lattner	33b73f9	2006-09-08 06:34:02 +0000	[diff] [blame]	5394
Andrew Lenharth	1d46352	2005-05-03 18:01:48 +0000	[diff] [blame]	5395	<!-- ======================================================================= -->
				5396	<div class="doc_subsection">
Nate Begeman	0f223bb	2006-01-13 23:26:38 +0000	[diff] [blame]	5397	<a name="int_manip">Bit Manipulation Intrinsics</a>
Andrew Lenharth	1d46352	2005-05-03 18:01:48 +0000	[diff] [blame]	5398	</div>
				5399
				5400	<div class="doc_text">
				5401	<p>
Nate Begeman	0f223bb	2006-01-13 23:26:38 +0000	[diff] [blame]	5402	LLVM provides intrinsics for a few important bit manipulation operations.
Andrew Lenharth	1d46352	2005-05-03 18:01:48 +0000	[diff] [blame]	5403	These allow efficient code generation for some algorithms.
				5404	</p>
				5405
				5406	</div>
				5407
				5408	<!-- _______________________________________________________________________ -->
				5409	<div class="doc_subsubsection">
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	5410	<a name="int_bswap">'<tt>llvm.bswap.*</tt>' Intrinsics</a>
Nate Begeman	0f223bb	2006-01-13 23:26:38 +0000	[diff] [blame]	5411	</div>
				5412
				5413	<div class="doc_text">
				5414
				5415	<h5>Syntax:</h5>
Reid Spencer	4eefaab	2007-04-01 08:04:23 +0000	[diff] [blame]	5416	<p>This is an overloaded intrinsic function. You can use bswap on any integer
Chandler Carruth	7132e00	2007-08-04 01:51:18 +0000	[diff] [blame]	5417	type that is an even number of bytes (i.e. BitWidth % 16 == 0).
Nate Begeman	0f223bb	2006-01-13 23:26:38 +0000	[diff] [blame]	5418	<pre>
Chandler Carruth	7132e00	2007-08-04 01:51:18 +0000	[diff] [blame]	5419	declare i16 @llvm.bswap.i16(i16 <id>)
				5420	declare i32 @llvm.bswap.i32(i32 <id>)
				5421	declare i64 @llvm.bswap.i64(i64 <id>)
Nate Begeman	0f223bb	2006-01-13 23:26:38 +0000	[diff] [blame]	5422	</pre>
				5423
				5424	<h5>Overview:</h5>
				5425
				5426	<p>
Reid Spencer	f361c4f	2007-04-02 02:25:19 +0000	[diff] [blame]	5427	The '<tt>llvm.bswap</tt>' family of intrinsics is used to byte swap integer
Reid Spencer	4eefaab	2007-04-01 08:04:23 +0000	[diff] [blame]	5428	values with an even number of bytes (positive multiple of 16 bits). These are
				5429	useful for performing operations on data that is not in the target's native
				5430	byte order.
Nate Begeman	0f223bb	2006-01-13 23:26:38 +0000	[diff] [blame]	5431	</p>
				5432
				5433	<h5>Semantics:</h5>
				5434
				5435	<p>
Chandler Carruth	7132e00	2007-08-04 01:51:18 +0000	[diff] [blame]	5436	The <tt>llvm.bswap.i16</tt> intrinsic returns an i16 value that has the high
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	5437	and low byte of the input i16 swapped. Similarly, the <tt>llvm.bswap.i32</tt>
				5438	intrinsic returns an i32 value that has the four bytes of the input i32
				5439	swapped, so that if the input bytes are numbered 0, 1, 2, 3 then the returned
Chandler Carruth	7132e00	2007-08-04 01:51:18 +0000	[diff] [blame]	5440	i32 will have its bytes in 3, 2, 1, 0 order. The <tt>llvm.bswap.i48</tt>,
				5441	<tt>llvm.bswap.i64</tt> and other intrinsics extend this concept to
Reid Spencer	4eefaab	2007-04-01 08:04:23 +0000	[diff] [blame]	5442	additional even-byte lengths (6 bytes, 8 bytes and more, respectively).
Nate Begeman	0f223bb	2006-01-13 23:26:38 +0000	[diff] [blame]	5443	</p>
				5444
				5445	</div>
				5446
				5447	<!-- _______________________________________________________________________ -->
				5448	<div class="doc_subsubsection">
Reid Spencer	b4f9a6f	2006-01-16 21:12:35 +0000	[diff] [blame]	5449	<a name="int_ctpop">'<tt>llvm.ctpop.*</tt>' Intrinsic</a>
Andrew Lenharth	1d46352	2005-05-03 18:01:48 +0000	[diff] [blame]	5450	</div>
				5451
				5452	<div class="doc_text">
				5453
				5454	<h5>Syntax:</h5>
Reid Spencer	4eefaab	2007-04-01 08:04:23 +0000	[diff] [blame]	5455	<p>This is an overloaded intrinsic. You can use llvm.ctpop on any integer bit
				5456	width. Not all targets support all bit widths however.
Andrew Lenharth	1d46352	2005-05-03 18:01:48 +0000	[diff] [blame]	5457	<pre>
Chandler Carruth	7132e00	2007-08-04 01:51:18 +0000	[diff] [blame]	5458	declare i8 @llvm.ctpop.i8 (i8 <src>)
				5459	declare i16 @llvm.ctpop.i16(i16 <src>)
Anton Korobeynikov	be9c93c	2007-03-22 00:02:17 +0000	[diff] [blame]	5460	declare i32 @llvm.ctpop.i32(i32 <src>)
Chandler Carruth	7132e00	2007-08-04 01:51:18 +0000	[diff] [blame]	5461	declare i64 @llvm.ctpop.i64(i64 <src>)
				5462	declare i256 @llvm.ctpop.i256(i256 <src>)
Andrew Lenharth	1d46352	2005-05-03 18:01:48 +0000	[diff] [blame]	5463	</pre>
				5464
				5465	<h5>Overview:</h5>
				5466
				5467	<p>
Chris Lattner	069b5bd	2006-01-16 22:38:59 +0000	[diff] [blame]	5468	The '<tt>llvm.ctpop</tt>' family of intrinsics counts the number of bits set in a
				5469	value.
Andrew Lenharth	1d46352	2005-05-03 18:01:48 +0000	[diff] [blame]	5470	</p>
				5471
				5472	<h5>Arguments:</h5>
				5473
				5474	<p>
Chris Lattner	573f64e	2005-05-07 01:46:40 +0000	[diff] [blame]	5475	The only argument is the value to be counted. The argument may be of any
Reid Spencer	3e628eb9	2007-01-04 16:43:23 +0000	[diff] [blame]	5476	integer type. The return type must match the argument type.
Andrew Lenharth	1d46352	2005-05-03 18:01:48 +0000	[diff] [blame]	5477	</p>
				5478
				5479	<h5>Semantics:</h5>
				5480
				5481	<p>
				5482	The '<tt>llvm.ctpop</tt>' intrinsic counts the 1's in a variable.
				5483	</p>
				5484	</div>
				5485
				5486	<!-- _______________________________________________________________________ -->
				5487	<div class="doc_subsubsection">
Chris Lattner	b748c67	2006-01-16 22:34:14 +0000	[diff] [blame]	5488	<a name="int_ctlz">'<tt>llvm.ctlz.*</tt>' Intrinsic</a>
Andrew Lenharth	1d46352	2005-05-03 18:01:48 +0000	[diff] [blame]	5489	</div>
				5490
				5491	<div class="doc_text">
				5492
				5493	<h5>Syntax:</h5>
Reid Spencer	4eefaab	2007-04-01 08:04:23 +0000	[diff] [blame]	5494	<p>This is an overloaded intrinsic. You can use <tt>llvm.ctlz</tt> on any
				5495	integer bit width. Not all targets support all bit widths however.
Andrew Lenharth	1d46352	2005-05-03 18:01:48 +0000	[diff] [blame]	5496	<pre>
Chandler Carruth	7132e00	2007-08-04 01:51:18 +0000	[diff] [blame]	5497	declare i8 @llvm.ctlz.i8 (i8 <src>)
				5498	declare i16 @llvm.ctlz.i16(i16 <src>)
Anton Korobeynikov	be9c93c	2007-03-22 00:02:17 +0000	[diff] [blame]	5499	declare i32 @llvm.ctlz.i32(i32 <src>)
Chandler Carruth	7132e00	2007-08-04 01:51:18 +0000	[diff] [blame]	5500	declare i64 @llvm.ctlz.i64(i64 <src>)
				5501	declare i256 @llvm.ctlz.i256(i256 <src>)
Andrew Lenharth	1d46352	2005-05-03 18:01:48 +0000	[diff] [blame]	5502	</pre>
				5503
				5504	<h5>Overview:</h5>
				5505
				5506	<p>
Reid Spencer	b4f9a6f	2006-01-16 21:12:35 +0000	[diff] [blame]	5507	The '<tt>llvm.ctlz</tt>' family of intrinsic functions counts the number of
				5508	leading zeros in a variable.
Andrew Lenharth	1d46352	2005-05-03 18:01:48 +0000	[diff] [blame]	5509	</p>
				5510
				5511	<h5>Arguments:</h5>
				5512
				5513	<p>
Chris Lattner	573f64e	2005-05-07 01:46:40 +0000	[diff] [blame]	5514	The only argument is the value to be counted. The argument may be of any
Reid Spencer	3e628eb9	2007-01-04 16:43:23 +0000	[diff] [blame]	5515	integer type. The return type must match the argument type.
Andrew Lenharth	1d46352	2005-05-03 18:01:48 +0000	[diff] [blame]	5516	</p>
				5517
				5518	<h5>Semantics:</h5>
				5519
				5520	<p>
Chris Lattner	efa20fa	2005-05-15 19:39:26 +0000	[diff] [blame]	5521	The '<tt>llvm.ctlz</tt>' intrinsic counts the leading (most significant) zeros
				5522	in a variable. If the src == 0 then the result is the size in bits of the type
Reid Spencer	b5ebf3d	2006-12-31 07:07:53 +0000	[diff] [blame]	5523	of src. For example, <tt>llvm.ctlz(i32 2) = 30</tt>.
Andrew Lenharth	1d46352	2005-05-03 18:01:48 +0000	[diff] [blame]	5524	</p>
				5525	</div>
Chris Lattner	3b4f437	2004-06-11 02:28:03 +0000	[diff] [blame]	5526
				5527
Chris Lattner	efa20fa	2005-05-15 19:39:26 +0000	[diff] [blame]	5528
				5529	<!-- _______________________________________________________________________ -->
				5530	<div class="doc_subsubsection">
Chris Lattner	b748c67	2006-01-16 22:34:14 +0000	[diff] [blame]	5531	<a name="int_cttz">'<tt>llvm.cttz.*</tt>' Intrinsic</a>
Chris Lattner	efa20fa	2005-05-15 19:39:26 +0000	[diff] [blame]	5532	</div>
				5533
				5534	<div class="doc_text">
				5535
				5536	<h5>Syntax:</h5>
Reid Spencer	4eefaab	2007-04-01 08:04:23 +0000	[diff] [blame]	5537	<p>This is an overloaded intrinsic. You can use <tt>llvm.cttz</tt> on any
				5538	integer bit width. Not all targets support all bit widths however.
Chris Lattner	efa20fa	2005-05-15 19:39:26 +0000	[diff] [blame]	5539	<pre>
Chandler Carruth	7132e00	2007-08-04 01:51:18 +0000	[diff] [blame]	5540	declare i8 @llvm.cttz.i8 (i8 <src>)
				5541	declare i16 @llvm.cttz.i16(i16 <src>)
Anton Korobeynikov	be9c93c	2007-03-22 00:02:17 +0000	[diff] [blame]	5542	declare i32 @llvm.cttz.i32(i32 <src>)
Chandler Carruth	7132e00	2007-08-04 01:51:18 +0000	[diff] [blame]	5543	declare i64 @llvm.cttz.i64(i64 <src>)
				5544	declare i256 @llvm.cttz.i256(i256 <src>)
Chris Lattner	efa20fa	2005-05-15 19:39:26 +0000	[diff] [blame]	5545	</pre>
				5546
				5547	<h5>Overview:</h5>
				5548
				5549	<p>
Reid Spencer	b4f9a6f	2006-01-16 21:12:35 +0000	[diff] [blame]	5550	The '<tt>llvm.cttz</tt>' family of intrinsic functions counts the number of
				5551	trailing zeros.
Chris Lattner	efa20fa	2005-05-15 19:39:26 +0000	[diff] [blame]	5552	</p>
				5553
				5554	<h5>Arguments:</h5>
				5555
				5556	<p>
				5557	The only argument is the value to be counted. The argument may be of any
Reid Spencer	3e628eb9	2007-01-04 16:43:23 +0000	[diff] [blame]	5558	integer type. The return type must match the argument type.
Chris Lattner	efa20fa	2005-05-15 19:39:26 +0000	[diff] [blame]	5559	</p>
				5560
				5561	<h5>Semantics:</h5>
				5562
				5563	<p>
				5564	The '<tt>llvm.cttz</tt>' intrinsic counts the trailing (least significant) zeros
				5565	in a variable. If the src == 0 then the result is the size in bits of the type
				5566	of src. For example, <tt>llvm.cttz(2) = 1</tt>.
				5567	</p>
				5568	</div>
				5569
Reid Spencer	8a5799f	2007-04-01 08:27:01 +0000	[diff] [blame]	5570	<!-- _______________________________________________________________________ -->
				5571	<div class="doc_subsubsection">
Reid Spencer	ea2945e	2007-04-10 02:51:31 +0000	[diff] [blame]	5572	<a name="int_part_select">'<tt>llvm.part.select.*</tt>' Intrinsic</a>
Reid Spencer	8bc7d95	2007-04-01 19:00:37 +0000	[diff] [blame]	5573	</div>
				5574
				5575	<div class="doc_text">
				5576
				5577	<h5>Syntax:</h5>
Reid Spencer	ea2945e	2007-04-10 02:51:31 +0000	[diff] [blame]	5578	<p>This is an overloaded intrinsic. You can use <tt>llvm.part.select</tt>
Reid Spencer	8bc7d95	2007-04-01 19:00:37 +0000	[diff] [blame]	5579	on any integer bit width.
				5580	<pre>
Chandler Carruth	7132e00	2007-08-04 01:51:18 +0000	[diff] [blame]	5581	declare i17 @llvm.part.select.i17 (i17 %val, i32 %loBit, i32 %hiBit)
				5582	declare i29 @llvm.part.select.i29 (i29 %val, i32 %loBit, i32 %hiBit)
Reid Spencer	8bc7d95	2007-04-01 19:00:37 +0000	[diff] [blame]	5583	</pre>
				5584
				5585	<h5>Overview:</h5>
Reid Spencer	ea2945e	2007-04-10 02:51:31 +0000	[diff] [blame]	5586	<p>The '<tt>llvm.part.select</tt>' family of intrinsic functions selects a
Reid Spencer	8bc7d95	2007-04-01 19:00:37 +0000	[diff] [blame]	5587	range of bits from an integer value and returns them in the same bit width as
				5588	the original value.</p>
				5589
				5590	<h5>Arguments:</h5>
				5591	<p>The first argument, <tt>%val</tt> and the result may be integer types of
				5592	any bit width but they must have the same bit width. The second and third
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	5593	arguments must be <tt>i32</tt> type since they specify only a bit index.</p>
Reid Spencer	8bc7d95	2007-04-01 19:00:37 +0000	[diff] [blame]	5594
				5595	<h5>Semantics:</h5>
Reid Spencer	ea2945e	2007-04-10 02:51:31 +0000	[diff] [blame]	5596	<p>The operation of the '<tt>llvm.part.select</tt>' intrinsic has two modes
Reid Spencer	96a5f02	2007-04-04 02:42:35 +0000	[diff] [blame]	5597	of operation: forwards and reverse. If <tt>%loBit</tt> is greater than
				5598	<tt>%hiBits</tt> then the intrinsic operates in reverse mode. Otherwise it
				5599	operates in forward mode.</p>
				5600	<p>In forward mode, this intrinsic is the equivalent of shifting <tt>%val</tt>
				5601	right by <tt>%loBit</tt> bits and then ANDing it with a mask with
Reid Spencer	8bc7d95	2007-04-01 19:00:37 +0000	[diff] [blame]	5602	only the <tt>%hiBit - %loBit</tt> bits set, as follows:</p>
				5603	<ol>
				5604	<li>The <tt>%val</tt> is shifted right (LSHR) by the number of bits specified
				5605	by <tt>%loBits</tt>. This normalizes the value to the low order bits.</li>
				5606	<li>The <tt>%loBits</tt> value is subtracted from the <tt>%hiBits</tt> value
				5607	to determine the number of bits to retain.</li>
				5608	<li>A mask of the retained bits is created by shifting a -1 value.</li>
				5609	<li>The mask is ANDed with <tt>%val</tt> to produce the result.
				5610	</ol>
Reid Spencer	70845c0	2007-05-14 16:14:57 +0000	[diff] [blame]	5611	<p>In reverse mode, a similar computation is made except that the bits are
				5612	returned in the reverse order. So, for example, if <tt>X</tt> has the value
				5613	<tt>i16 0x0ACF (101011001111)</tt> and we apply
				5614	<tt>part.select(i16 X, 8, 3)</tt> to it, we get back the value
				5615	<tt>i16 0x0026 (000000100110)</tt>.</p>
Reid Spencer	8bc7d95	2007-04-01 19:00:37 +0000	[diff] [blame]	5616	</div>
				5617
Reid Spencer	5bf54c8	2007-04-11 23:23:49 +0000	[diff] [blame]	5618	<div class="doc_subsubsection">
				5619	<a name="int_part_set">'<tt>llvm.part.set.*</tt>' Intrinsic</a>
				5620	</div>
				5621
				5622	<div class="doc_text">
				5623
				5624	<h5>Syntax:</h5>
				5625	<p>This is an overloaded intrinsic. You can use <tt>llvm.part.set</tt>
				5626	on any integer bit width.
				5627	<pre>
Chandler Carruth	7132e00	2007-08-04 01:51:18 +0000	[diff] [blame]	5628	declare i17 @llvm.part.set.i17.i9 (i17 %val, i9 %repl, i32 %lo, i32 %hi)
				5629	declare i29 @llvm.part.set.i29.i9 (i29 %val, i9 %repl, i32 %lo, i32 %hi)
Reid Spencer	5bf54c8	2007-04-11 23:23:49 +0000	[diff] [blame]	5630	</pre>
				5631
				5632	<h5>Overview:</h5>
				5633	<p>The '<tt>llvm.part.set</tt>' family of intrinsic functions replaces a range
				5634	of bits in an integer value with another integer value. It returns the integer
				5635	with the replaced bits.</p>
				5636
				5637	<h5>Arguments:</h5>
				5638	<p>The first argument, <tt>%val</tt> and the result may be integer types of
				5639	any bit width but they must have the same bit width. <tt>%val</tt> is the value
				5640	whose bits will be replaced. The second argument, <tt>%repl</tt> may be an
				5641	integer of any bit width. The third and fourth arguments must be <tt>i32</tt>
				5642	type since they specify only a bit index.</p>
				5643
				5644	<h5>Semantics:</h5>
				5645	<p>The operation of the '<tt>llvm.part.set</tt>' intrinsic has two modes
				5646	of operation: forwards and reverse. If <tt>%lo</tt> is greater than
				5647	<tt>%hi</tt> then the intrinsic operates in reverse mode. Otherwise it
				5648	operates in forward mode.</p>
				5649	<p>For both modes, the <tt>%repl</tt> value is prepared for use by either
				5650	truncating it down to the size of the replacement area or zero extending it
				5651	up to that size.</p>
				5652	<p>In forward mode, the bits between <tt>%lo</tt> and <tt>%hi</tt> (inclusive)
				5653	are replaced with corresponding bits from <tt>%repl</tt>. That is the 0th bit
				5654	in <tt>%repl</tt> replaces the <tt>%lo</tt>th bit in <tt>%val</tt> and etc. up
				5655	to the <tt>%hi</tt>th bit.
Reid Spencer	146281c	2007-05-14 16:50:20 +0000	[diff] [blame]	5656	<p>In reverse mode, a similar computation is made except that the bits are
				5657	reversed. That is, the <tt>0</tt>th bit in <tt>%repl</tt> replaces the
				5658	<tt>%hi</tt> bit in <tt>%val</tt> and etc. down to the <tt>%lo</tt>th bit.
Reid Spencer	5bf54c8	2007-04-11 23:23:49 +0000	[diff] [blame]	5659	<h5>Examples:</h5>
				5660	<pre>
Reid Spencer	c70afc3	2007-04-12 01:03:03 +0000	[diff] [blame]	5661	llvm.part.set(0xFFFF, 0, 4, 7) -> 0xFF0F
Reid Spencer	146281c	2007-05-14 16:50:20 +0000	[diff] [blame]	5662	llvm.part.set(0xFFFF, 0, 7, 4) -> 0xFF0F
				5663	llvm.part.set(0xFFFF, 1, 7, 4) -> 0xFF8F
				5664	llvm.part.set(0xFFFF, F, 8, 3) -> 0xFFE7
Reid Spencer	c70afc3	2007-04-12 01:03:03 +0000	[diff] [blame]	5665	llvm.part.set(0xFFFF, 0, 3, 8) -> 0xFE07
Reid Spencer	7972c47	2007-04-11 23:49:50 +0000	[diff] [blame]	5666	</pre>
Reid Spencer	5bf54c8	2007-04-11 23:23:49 +0000	[diff] [blame]	5667	</div>
				5668
Chris Lattner	941515c	2004-01-06 05:31:32 +0000	[diff] [blame]	5669	<!-- ======================================================================= -->
				5670	<div class="doc_subsection">
				5671	<a name="int_debugger">Debugger Intrinsics</a>
				5672	</div>
				5673
				5674	<div class="doc_text">
				5675	<p>
				5676	The LLVM debugger intrinsics (which all start with <tt>llvm.dbg.</tt> prefix),
				5677	are described in the <a
				5678	href="SourceLevelDebugging.html#format_common_intrinsics">LLVM Source Level
				5679	Debugging</a> document.
				5680	</p>
				5681	</div>
				5682
				5683
Jim Laskey	2211f49	2007-03-14 19:31:19 +0000	[diff] [blame]	5684	<!-- ======================================================================= -->
				5685	<div class="doc_subsection">
				5686	<a name="int_eh">Exception Handling Intrinsics</a>
				5687	</div>
				5688
				5689	<div class="doc_text">
				5690	<p> The LLVM exception handling intrinsics (which all start with
				5691	<tt>llvm.eh.</tt> prefix), are described in the <a
				5692	href="ExceptionHandling.html#format_common_intrinsics">LLVM Exception
				5693	Handling</a> document. </p>
				5694	</div>
				5695
Tanya Lattner	cb1b960	2007-06-15 20:50:54 +0000	[diff] [blame]	5696	<!-- ======================================================================= -->
				5697	<div class="doc_subsection">
Duncan Sands	86e0119	2007-09-11 14:10:23 +0000	[diff] [blame]	5698	<a name="int_trampoline">Trampoline Intrinsic</a>
Duncan Sands	644f917	2007-07-27 12:58:54 +0000	[diff] [blame]	5699	</div>
				5700
				5701	<div class="doc_text">
				5702	<p>
Duncan Sands	86e0119	2007-09-11 14:10:23 +0000	[diff] [blame]	5703	This intrinsic makes it possible to excise one parameter, marked with
Duncan Sands	644f917	2007-07-27 12:58:54 +0000	[diff] [blame]	5704	the <tt>nest</tt> attribute, from a function. The result is a callable
				5705	function pointer lacking the nest parameter - the caller does not need
				5706	to provide a value for it. Instead, the value to use is stored in
				5707	advance in a "trampoline", a block of memory usually allocated
				5708	on the stack, which also contains code to splice the nest value into the
				5709	argument list. This is used to implement the GCC nested function address
				5710	extension.
				5711	</p>
				5712	<p>
				5713	For example, if the function is
				5714	<tt>i32 f(i8* nest %c, i32 %x, i32 %y)</tt> then the resulting function
Bill Wendling	252570f	2007-09-22 09:23:55 +0000	[diff] [blame]	5715	pointer has signature <tt>i32 (i32, i32)*</tt>. It can be created as follows:</p>
Duncan Sands	644f917	2007-07-27 12:58:54 +0000	[diff] [blame]	5716	<pre>
Duncan Sands	86e0119	2007-09-11 14:10:23 +0000	[diff] [blame]	5717	%tramp = alloca [10 x i8], align 4 ; size and alignment only correct for X86
				5718	%tramp1 = getelementptr [10 x i8]* %tramp, i32 0, i32 0
				5719	%p = call i8* @llvm.init.trampoline( i8* %tramp1, i8* bitcast (i32 (i8* nest , i32, i32)* @f to i8), i8 %nval )
				5720	%fp = bitcast i8* %p to i32 (i32, i32)*
Duncan Sands	644f917	2007-07-27 12:58:54 +0000	[diff] [blame]	5721	</pre>
Bill Wendling	252570f	2007-09-22 09:23:55 +0000	[diff] [blame]	5722	<p>The call <tt>%val = call i32 %fp( i32 %x, i32 %y )</tt> is then equivalent
				5723	to <tt>%val = call i32 %f( i8* %nval, i32 %x, i32 %y )</tt>.</p>
Duncan Sands	644f917	2007-07-27 12:58:54 +0000	[diff] [blame]	5724	</div>
				5725
				5726	<!-- _______________________________________________________________________ -->
				5727	<div class="doc_subsubsection">
				5728	<a name="int_it">'<tt>llvm.init.trampoline</tt>' Intrinsic</a>
				5729	</div>
				5730	<div class="doc_text">
				5731	<h5>Syntax:</h5>
				5732	<pre>
Duncan Sands	86e0119	2007-09-11 14:10:23 +0000	[diff] [blame]	5733	declare i8* @llvm.init.trampoline(i8* <tramp>, i8* <func>, i8* <nval>)
Duncan Sands	644f917	2007-07-27 12:58:54 +0000	[diff] [blame]	5734	</pre>
				5735	<h5>Overview:</h5>
				5736	<p>
Duncan Sands	86e0119	2007-09-11 14:10:23 +0000	[diff] [blame]	5737	This fills the memory pointed to by <tt>tramp</tt> with code
				5738	and returns a function pointer suitable for executing it.
Duncan Sands	644f917	2007-07-27 12:58:54 +0000	[diff] [blame]	5739	</p>
				5740	<h5>Arguments:</h5>
				5741	<p>
				5742	The <tt>llvm.init.trampoline</tt> intrinsic takes three arguments, all
				5743	pointers. The <tt>tramp</tt> argument must point to a sufficiently large
				5744	and sufficiently aligned block of memory; this memory is written to by the
Duncan Sands	f2bcd37	2007-08-22 23:39:54 +0000	[diff] [blame]	5745	intrinsic. Note that the size and the alignment are target-specific - LLVM
				5746	currently provides no portable way of determining them, so a front-end that
				5747	generates this intrinsic needs to have some target-specific knowledge.
				5748	The <tt>func</tt> argument must hold a function bitcast to an <tt>i8*</tt>.
Duncan Sands	644f917	2007-07-27 12:58:54 +0000	[diff] [blame]	5749	</p>
				5750	<h5>Semantics:</h5>
				5751	<p>
				5752	The block of memory pointed to by <tt>tramp</tt> is filled with target
Duncan Sands	86e0119	2007-09-11 14:10:23 +0000	[diff] [blame]	5753	dependent code, turning it into a function. A pointer to this function is
				5754	returned, but needs to be bitcast to an
Duncan Sands	644f917	2007-07-27 12:58:54 +0000	[diff] [blame]	5755	<a href="#int_trampoline">appropriate function pointer type</a>
Duncan Sands	86e0119	2007-09-11 14:10:23 +0000	[diff] [blame]	5756	before being called. The new function's signature is the same as that of
				5757	<tt>func</tt> with any arguments marked with the <tt>nest</tt> attribute
				5758	removed. At most one such <tt>nest</tt> argument is allowed, and it must be
				5759	of pointer type. Calling the new function is equivalent to calling
				5760	<tt>func</tt> with the same argument list, but with <tt>nval</tt> used for the
				5761	missing <tt>nest</tt> argument. If, after calling
				5762	<tt>llvm.init.trampoline</tt>, the memory pointed to by <tt>tramp</tt> is
				5763	modified, then the effect of any later call to the returned function pointer is
				5764	undefined.
Duncan Sands	644f917	2007-07-27 12:58:54 +0000	[diff] [blame]	5765	</p>
				5766	</div>
				5767
				5768	<!-- ======================================================================= -->
				5769	<div class="doc_subsection">
Andrew Lenharth	9b254ee	2008-02-16 01:24:58 +0000	[diff] [blame]	5770	<a name="int_atomics">Atomic Operations and Synchronization Intrinsics</a>
				5771	</div>
				5772
				5773	<div class="doc_text">
				5774	<p>
				5775	These intrinsic functions expand the "universal IR" of LLVM to represent
				5776	hardware constructs for atomic operations and memory synchronization. This
				5777	provides an interface to the hardware, not an interface to the programmer. It
Chris Lattner	67c37d1	2008-08-05 18:29:16 +0000	[diff] [blame]	5778	is aimed at a low enough level to allow any programming models or APIs
				5779	(Application Programming Interfaces) which
Andrew Lenharth	9b254ee	2008-02-16 01:24:58 +0000	[diff] [blame]	5780	need atomic behaviors to map cleanly onto it. It is also modeled primarily on
				5781	hardware behavior. Just as hardware provides a "universal IR" for source
				5782	languages, it also provides a starting point for developing a "universal"
				5783	atomic operation and synchronization IR.
				5784	</p>
				5785	<p>
				5786	These do <em>not</em> form an API such as high-level threading libraries,
				5787	software transaction memory systems, atomic primitives, and intrinsic
				5788	functions as found in BSD, GNU libc, atomic_ops, APR, and other system and
				5789	application libraries. The hardware interface provided by LLVM should allow
				5790	a clean implementation of all of these APIs and parallel programming models.
				5791	No one model or paradigm should be selected above others unless the hardware
				5792	itself ubiquitously does so.
				5793
				5794	</p>
				5795	</div>
				5796
				5797	<!-- _______________________________________________________________________ -->
				5798	<div class="doc_subsubsection">
				5799	<a name="int_memory_barrier">'<tt>llvm.memory.barrier</tt>' Intrinsic</a>
				5800	</div>
				5801	<div class="doc_text">
				5802	<h5>Syntax:</h5>
				5803	<pre>
				5804	declare void @llvm.memory.barrier( i1 <ll>, i1 <ls>, i1 <sl>, i1 <ss>,
				5805	i1 <device> )
				5806
				5807	</pre>
				5808	<h5>Overview:</h5>
				5809	<p>
				5810	The <tt>llvm.memory.barrier</tt> intrinsic guarantees ordering between
				5811	specific pairs of memory access types.
				5812	</p>
				5813	<h5>Arguments:</h5>
				5814	<p>
				5815	The <tt>llvm.memory.barrier</tt> intrinsic requires five boolean arguments.
				5816	The first four arguments enables a specific barrier as listed below. The fith
				5817	argument specifies that the barrier applies to io or device or uncached memory.
				5818
				5819	</p>
				5820	<ul>
				5821	<li><tt>ll</tt>: load-load barrier</li>
				5822	<li><tt>ls</tt>: load-store barrier</li>
				5823	<li><tt>sl</tt>: store-load barrier</li>
				5824	<li><tt>ss</tt>: store-store barrier</li>
				5825	<li><tt>device</tt>: barrier applies to device and uncached memory also.
				5826	</ul>
				5827	<h5>Semantics:</h5>
				5828	<p>
				5829	This intrinsic causes the system to enforce some ordering constraints upon
				5830	the loads and stores of the program. This barrier does not indicate
				5831	<em>when</em> any events will occur, it only enforces an <em>order</em> in
				5832	which they occur. For any of the specified pairs of load and store operations
				5833	(f.ex. load-load, or store-load), all of the first operations preceding the
				5834	barrier will complete before any of the second operations succeeding the
				5835	barrier begin. Specifically the semantics for each pairing is as follows:
				5836	</p>
				5837	<ul>
				5838	<li><tt>ll</tt>: All loads before the barrier must complete before any load
				5839	after the barrier begins.</li>
				5840
				5841	<li><tt>ls</tt>: All loads before the barrier must complete before any
				5842	store after the barrier begins.</li>
				5843	<li><tt>ss</tt>: All stores before the barrier must complete before any
				5844	store after the barrier begins.</li>
				5845	<li><tt>sl</tt>: All stores before the barrier must complete before any
				5846	load after the barrier begins.</li>
				5847	</ul>
				5848	<p>
				5849	These semantics are applied with a logical "and" behavior when more than one
				5850	is enabled in a single memory barrier intrinsic.
				5851	</p>
				5852	<p>
				5853	Backends may implement stronger barriers than those requested when they do not
				5854	support as fine grained a barrier as requested. Some architectures do not
				5855	need all types of barriers and on such architectures, these become noops.
				5856	</p>
				5857	<h5>Example:</h5>
				5858	<pre>
				5859	%ptr = malloc i32
				5860	store i32 4, %ptr
				5861
				5862	%result1 = load i32* %ptr <i>; yields {i32}:result1 = 4</i>
				5863	call void @llvm.memory.barrier( i1 false, i1 true, i1 false, i1 false )
				5864	<i>; guarantee the above finishes</i>
				5865	store i32 8, %ptr <i>; before this begins</i>
				5866	</pre>
				5867	</div>
				5868
Andrew Lenharth	9552894	2008-02-21 06:45:13 +0000	[diff] [blame]	5869	<!-- _______________________________________________________________________ -->
				5870	<div class="doc_subsubsection">
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	5871	<a name="int_atomic_cmp_swap">'<tt>llvm.atomic.cmp.swap.*</tt>' Intrinsic</a>
Andrew Lenharth	9552894	2008-02-21 06:45:13 +0000	[diff] [blame]	5872	</div>
				5873	<div class="doc_text">
				5874	<h5>Syntax:</h5>
				5875	<p>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	5876	This is an overloaded intrinsic. You can use <tt>llvm.atomic.cmp.swap</tt> on
				5877	any integer bit width and for different address spaces. Not all targets
				5878	support all bit widths however.</p>
Andrew Lenharth	9552894	2008-02-21 06:45:13 +0000	[diff] [blame]	5879
				5880	<pre>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	5881	declare i8 @llvm.atomic.cmp.swap.i8.p0i8( i8* <ptr>, i8 <cmp>, i8 <val> )
				5882	declare i16 @llvm.atomic.cmp.swap.i16.p0i16( i16* <ptr>, i16 <cmp>, i16 <val> )
				5883	declare i32 @llvm.atomic.cmp.swap.i32.p0i32( i32* <ptr>, i32 <cmp>, i32 <val> )
				5884	declare i64 @llvm.atomic.cmp.swap.i64.p0i64( i64* <ptr>, i64 <cmp>, i64 <val> )
Andrew Lenharth	9552894	2008-02-21 06:45:13 +0000	[diff] [blame]	5885
				5886	</pre>
				5887	<h5>Overview:</h5>
				5888	<p>
				5889	This loads a value in memory and compares it to a given value. If they are
				5890	equal, it stores a new value into the memory.
				5891	</p>
				5892	<h5>Arguments:</h5>
				5893	<p>
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	5894	The <tt>llvm.atomic.cmp.swap</tt> intrinsic takes three arguments. The result as
Andrew Lenharth	9552894	2008-02-21 06:45:13 +0000	[diff] [blame]	5895	well as both <tt>cmp</tt> and <tt>val</tt> must be integer values with the
				5896	same bit width. The <tt>ptr</tt> argument must be a pointer to a value of
				5897	this integer type. While any bit width integer may be used, targets may only
				5898	lower representations they support in hardware.
				5899
				5900	</p>
				5901	<h5>Semantics:</h5>
				5902	<p>
				5903	This entire intrinsic must be executed atomically. It first loads the value
				5904	in memory pointed to by <tt>ptr</tt> and compares it with the value
				5905	<tt>cmp</tt>. If they are equal, <tt>val</tt> is stored into the memory. The
				5906	loaded value is yielded in all cases. This provides the equivalent of an
				5907	atomic compare-and-swap operation within the SSA framework.
				5908	</p>
				5909	<h5>Examples:</h5>
				5910
				5911	<pre>
				5912	%ptr = malloc i32
				5913	store i32 4, %ptr
				5914
				5915	%val1 = add i32 4, 4
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	5916	%result1 = call i32 @llvm.atomic.cmp.swap.i32.p0i32( i32* %ptr, i32 4, %val1 )
Andrew Lenharth	9552894	2008-02-21 06:45:13 +0000	[diff] [blame]	5917	<i>; yields {i32}:result1 = 4</i>
				5918	%stored1 = icmp eq i32 %result1, 4 <i>; yields {i1}:stored1 = true</i>
				5919	%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = 8</i>
				5920
				5921	%val2 = add i32 1, 1
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	5922	%result2 = call i32 @llvm.atomic.cmp.swap.i32.p0i32( i32* %ptr, i32 5, %val2 )
Andrew Lenharth	9552894	2008-02-21 06:45:13 +0000	[diff] [blame]	5923	<i>; yields {i32}:result2 = 8</i>
				5924	%stored2 = icmp eq i32 %result2, 5 <i>; yields {i1}:stored2 = false</i>
				5925
				5926	%memval2 = load i32* %ptr <i>; yields {i32}:memval2 = 8</i>
				5927	</pre>
				5928	</div>
				5929
				5930	<!-- _______________________________________________________________________ -->
				5931	<div class="doc_subsubsection">
				5932	<a name="int_atomic_swap">'<tt>llvm.atomic.swap.*</tt>' Intrinsic</a>
				5933	</div>
				5934	<div class="doc_text">
				5935	<h5>Syntax:</h5>
				5936
				5937	<p>
				5938	This is an overloaded intrinsic. You can use <tt>llvm.atomic.swap</tt> on any
				5939	integer bit width. Not all targets support all bit widths however.</p>
				5940	<pre>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	5941	declare i8 @llvm.atomic.swap.i8.p0i8( i8* <ptr>, i8 <val> )
				5942	declare i16 @llvm.atomic.swap.i16.p0i16( i16* <ptr>, i16 <val> )
				5943	declare i32 @llvm.atomic.swap.i32.p0i32( i32* <ptr>, i32 <val> )
				5944	declare i64 @llvm.atomic.swap.i64.p0i64( i64* <ptr>, i64 <val> )
Andrew Lenharth	9552894	2008-02-21 06:45:13 +0000	[diff] [blame]	5945
				5946	</pre>
				5947	<h5>Overview:</h5>
				5948	<p>
				5949	This intrinsic loads the value stored in memory at <tt>ptr</tt> and yields
				5950	the value from memory. It then stores the value in <tt>val</tt> in the memory
				5951	at <tt>ptr</tt>.
				5952	</p>
				5953	<h5>Arguments:</h5>
				5954
				5955	<p>
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	5956	The <tt>llvm.atomic.swap</tt> intrinsic takes two arguments. Both the
Andrew Lenharth	9552894	2008-02-21 06:45:13 +0000	[diff] [blame]	5957	<tt>val</tt> argument and the result must be integers of the same bit width.
				5958	The first argument, <tt>ptr</tt>, must be a pointer to a value of this
				5959	integer type. The targets may only lower integer representations they
				5960	support.
				5961	</p>
				5962	<h5>Semantics:</h5>
				5963	<p>
				5964	This intrinsic loads the value pointed to by <tt>ptr</tt>, yields it, and
				5965	stores <tt>val</tt> back into <tt>ptr</tt> atomically. This provides the
				5966	equivalent of an atomic swap operation within the SSA framework.
				5967
				5968	</p>
				5969	<h5>Examples:</h5>
				5970	<pre>
				5971	%ptr = malloc i32
				5972	store i32 4, %ptr
				5973
				5974	%val1 = add i32 4, 4
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	5975	%result1 = call i32 @llvm.atomic.swap.i32.p0i32( i32* %ptr, i32 %val1 )
Andrew Lenharth	9552894	2008-02-21 06:45:13 +0000	[diff] [blame]	5976	<i>; yields {i32}:result1 = 4</i>
				5977	%stored1 = icmp eq i32 %result1, 4 <i>; yields {i1}:stored1 = true</i>
				5978	%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = 8</i>
				5979
				5980	%val2 = add i32 1, 1
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	5981	%result2 = call i32 @llvm.atomic.swap.i32.p0i32( i32* %ptr, i32 %val2 )
Andrew Lenharth	9552894	2008-02-21 06:45:13 +0000	[diff] [blame]	5982	<i>; yields {i32}:result2 = 8</i>
				5983
				5984	%stored2 = icmp eq i32 %result2, 8 <i>; yields {i1}:stored2 = true</i>
				5985	%memval2 = load i32* %ptr <i>; yields {i32}:memval2 = 2</i>
				5986	</pre>
				5987	</div>
				5988
				5989	<!-- _______________________________________________________________________ -->
				5990	<div class="doc_subsubsection">
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	5991	<a name="int_atomic_load_add">'<tt>llvm.atomic.load.add.*</tt>' Intrinsic</a>
Andrew Lenharth	9552894	2008-02-21 06:45:13 +0000	[diff] [blame]	5992
				5993	</div>
				5994	<div class="doc_text">
				5995	<h5>Syntax:</h5>
				5996	<p>
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	5997	This is an overloaded intrinsic. You can use <tt>llvm.atomic.load.add</tt> on any
Andrew Lenharth	9552894	2008-02-21 06:45:13 +0000	[diff] [blame]	5998	integer bit width. Not all targets support all bit widths however.</p>
				5999	<pre>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6000	declare i8 @llvm.atomic.load.add.i8..p0i8( i8* <ptr>, i8 <delta> )
				6001	declare i16 @llvm.atomic.load.add.i16..p0i16( i16* <ptr>, i16 <delta> )
				6002	declare i32 @llvm.atomic.load.add.i32..p0i32( i32* <ptr>, i32 <delta> )
				6003	declare i64 @llvm.atomic.load.add.i64..p0i64( i64* <ptr>, i64 <delta> )
Andrew Lenharth	9552894	2008-02-21 06:45:13 +0000	[diff] [blame]	6004
				6005	</pre>
				6006	<h5>Overview:</h5>
				6007	<p>
				6008	This intrinsic adds <tt>delta</tt> to the value stored in memory at
				6009	<tt>ptr</tt>. It yields the original value at <tt>ptr</tt>.
				6010	</p>
				6011	<h5>Arguments:</h5>
				6012	<p>
				6013
				6014	The intrinsic takes two arguments, the first a pointer to an integer value
				6015	and the second an integer value. The result is also an integer value. These
				6016	integer types can have any bit width, but they must all have the same bit
				6017	width. The targets may only lower integer representations they support.
				6018	</p>
				6019	<h5>Semantics:</h5>
				6020	<p>
				6021	This intrinsic does a series of operations atomically. It first loads the
				6022	value stored at <tt>ptr</tt>. It then adds <tt>delta</tt>, stores the result
				6023	to <tt>ptr</tt>. It yields the original value stored at <tt>ptr</tt>.
				6024	</p>
				6025
				6026	<h5>Examples:</h5>
				6027	<pre>
				6028	%ptr = malloc i32
				6029	store i32 4, %ptr
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6030	%result1 = call i32 @llvm.atomic.load.add.i32.p0i32( i32* %ptr, i32 4 )
Andrew Lenharth	9552894	2008-02-21 06:45:13 +0000	[diff] [blame]	6031	<i>; yields {i32}:result1 = 4</i>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6032	%result2 = call i32 @llvm.atomic.load.add.i32.p0i32( i32* %ptr, i32 2 )
Andrew Lenharth	9552894	2008-02-21 06:45:13 +0000	[diff] [blame]	6033	<i>; yields {i32}:result2 = 8</i>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6034	%result3 = call i32 @llvm.atomic.load.add.i32.p0i32( i32* %ptr, i32 5 )
Andrew Lenharth	9552894	2008-02-21 06:45:13 +0000	[diff] [blame]	6035	<i>; yields {i32}:result3 = 10</i>
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6036	%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = 15</i>
Andrew Lenharth	9552894	2008-02-21 06:45:13 +0000	[diff] [blame]	6037	</pre>
				6038	</div>
				6039
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6040	<!-- _______________________________________________________________________ -->
				6041	<div class="doc_subsubsection">
				6042	<a name="int_atomic_load_sub">'<tt>llvm.atomic.load.sub.*</tt>' Intrinsic</a>
				6043
				6044	</div>
				6045	<div class="doc_text">
				6046	<h5>Syntax:</h5>
				6047	<p>
				6048	This is an overloaded intrinsic. You can use <tt>llvm.atomic.load.sub</tt> on
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6049	any integer bit width and for different address spaces. Not all targets
				6050	support all bit widths however.</p>
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6051	<pre>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6052	declare i8 @llvm.atomic.load.sub.i8.p0i32( i8* <ptr>, i8 <delta> )
				6053	declare i16 @llvm.atomic.load.sub.i16.p0i32( i16* <ptr>, i16 <delta> )
				6054	declare i32 @llvm.atomic.load.sub.i32.p0i32( i32* <ptr>, i32 <delta> )
				6055	declare i64 @llvm.atomic.load.sub.i64.p0i32( i64* <ptr>, i64 <delta> )
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6056
				6057	</pre>
				6058	<h5>Overview:</h5>
				6059	<p>
				6060	This intrinsic subtracts <tt>delta</tt> to the value stored in memory at
				6061	<tt>ptr</tt>. It yields the original value at <tt>ptr</tt>.
				6062	</p>
				6063	<h5>Arguments:</h5>
				6064	<p>
				6065
				6066	The intrinsic takes two arguments, the first a pointer to an integer value
				6067	and the second an integer value. The result is also an integer value. These
				6068	integer types can have any bit width, but they must all have the same bit
				6069	width. The targets may only lower integer representations they support.
				6070	</p>
				6071	<h5>Semantics:</h5>
				6072	<p>
				6073	This intrinsic does a series of operations atomically. It first loads the
				6074	value stored at <tt>ptr</tt>. It then subtracts <tt>delta</tt>, stores the
				6075	result to <tt>ptr</tt>. It yields the original value stored at <tt>ptr</tt>.
				6076	</p>
				6077
				6078	<h5>Examples:</h5>
				6079	<pre>
				6080	%ptr = malloc i32
				6081	store i32 8, %ptr
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6082	%result1 = call i32 @llvm.atomic.load.sub.i32.p0i32( i32* %ptr, i32 4 )
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6083	<i>; yields {i32}:result1 = 8</i>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6084	%result2 = call i32 @llvm.atomic.load.sub.i32.p0i32( i32* %ptr, i32 2 )
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6085	<i>; yields {i32}:result2 = 4</i>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6086	%result3 = call i32 @llvm.atomic.load.sub.i32.p0i32( i32* %ptr, i32 5 )
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6087	<i>; yields {i32}:result3 = 2</i>
				6088	%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = -3</i>
				6089	</pre>
				6090	</div>
				6091
				6092	<!-- _______________________________________________________________________ -->
				6093	<div class="doc_subsubsection">
				6094	<a name="int_atomic_load_and">'<tt>llvm.atomic.load.and.*</tt>' Intrinsic</a><br>
				6095	<a name="int_atomic_load_nand">'<tt>llvm.atomic.load.nand.*</tt>' Intrinsic</a><br>
				6096	<a name="int_atomic_load_or">'<tt>llvm.atomic.load.or.*</tt>' Intrinsic</a><br>
				6097	<a name="int_atomic_load_xor">'<tt>llvm.atomic.load.xor.*</tt>' Intrinsic</a><br>
				6098
				6099	</div>
				6100	<div class="doc_text">
				6101	<h5>Syntax:</h5>
				6102	<p>
				6103	These are overloaded intrinsics. You can use <tt>llvm.atomic.load_and</tt>,
				6104	<tt>llvm.atomic.load_nand</tt>, <tt>llvm.atomic.load_or</tt>, and
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6105	<tt>llvm.atomic.load_xor</tt> on any integer bit width and for different
				6106	address spaces. Not all targets support all bit widths however.</p>
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6107	<pre>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6108	declare i8 @llvm.atomic.load.and.i8.p0i8( i8* <ptr>, i8 <delta> )
				6109	declare i16 @llvm.atomic.load.and.i16.p0i16( i16* <ptr>, i16 <delta> )
				6110	declare i32 @llvm.atomic.load.and.i32.p0i32( i32* <ptr>, i32 <delta> )
				6111	declare i64 @llvm.atomic.load.and.i64.p0i64( i64* <ptr>, i64 <delta> )
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6112
				6113	</pre>
				6114
				6115	<pre>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6116	declare i8 @llvm.atomic.load.or.i8.p0i8( i8* <ptr>, i8 <delta> )
				6117	declare i16 @llvm.atomic.load.or.i16.p0i16( i16* <ptr>, i16 <delta> )
				6118	declare i32 @llvm.atomic.load.or.i32.p0i32( i32* <ptr>, i32 <delta> )
				6119	declare i64 @llvm.atomic.load.or.i64.p0i64( i64* <ptr>, i64 <delta> )
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6120
				6121	</pre>
				6122
				6123	<pre>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6124	declare i8 @llvm.atomic.load.nand.i8.p0i32( i8* <ptr>, i8 <delta> )
				6125	declare i16 @llvm.atomic.load.nand.i16.p0i32( i16* <ptr>, i16 <delta> )
				6126	declare i32 @llvm.atomic.load.nand.i32.p0i32( i32* <ptr>, i32 <delta> )
				6127	declare i64 @llvm.atomic.load.nand.i64.p0i32( i64* <ptr>, i64 <delta> )
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6128
				6129	</pre>
				6130
				6131	<pre>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6132	declare i8 @llvm.atomic.load.xor.i8.p0i32( i8* <ptr>, i8 <delta> )
				6133	declare i16 @llvm.atomic.load.xor.i16.p0i32( i16* <ptr>, i16 <delta> )
				6134	declare i32 @llvm.atomic.load.xor.i32.p0i32( i32* <ptr>, i32 <delta> )
				6135	declare i64 @llvm.atomic.load.xor.i64.p0i32( i64* <ptr>, i64 <delta> )
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6136
				6137	</pre>
				6138	<h5>Overview:</h5>
				6139	<p>
				6140	These intrinsics bitwise the operation (and, nand, or, xor) <tt>delta</tt> to
				6141	the value stored in memory at <tt>ptr</tt>. It yields the original value
				6142	at <tt>ptr</tt>.
				6143	</p>
				6144	<h5>Arguments:</h5>
				6145	<p>
				6146
				6147	These intrinsics take two arguments, the first a pointer to an integer value
				6148	and the second an integer value. The result is also an integer value. These
				6149	integer types can have any bit width, but they must all have the same bit
				6150	width. The targets may only lower integer representations they support.
				6151	</p>
				6152	<h5>Semantics:</h5>
				6153	<p>
				6154	These intrinsics does a series of operations atomically. They first load the
				6155	value stored at <tt>ptr</tt>. They then do the bitwise operation
				6156	<tt>delta</tt>, store the result to <tt>ptr</tt>. They yield the original
				6157	value stored at <tt>ptr</tt>.
				6158	</p>
				6159
				6160	<h5>Examples:</h5>
				6161	<pre>
				6162	%ptr = malloc i32
				6163	store i32 0x0F0F, %ptr
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6164	%result0 = call i32 @llvm.atomic.load.nand.i32.p0i32( i32* %ptr, i32 0xFF )
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6165	<i>; yields {i32}:result0 = 0x0F0F</i>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6166	%result1 = call i32 @llvm.atomic.load.and.i32.p0i32( i32* %ptr, i32 0xFF )
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6167	<i>; yields {i32}:result1 = 0xFFFFFFF0</i>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6168	%result2 = call i32 @llvm.atomic.load.or.i32.p0i32( i32* %ptr, i32 0F )
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6169	<i>; yields {i32}:result2 = 0xF0</i>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6170	%result3 = call i32 @llvm.atomic.load.xor.i32.p0i32( i32* %ptr, i32 0F )
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6171	<i>; yields {i32}:result3 = FF</i>
				6172	%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = F0</i>
				6173	</pre>
				6174	</div>
				6175
				6176
				6177	<!-- _______________________________________________________________________ -->
				6178	<div class="doc_subsubsection">
				6179	<a name="int_atomic_load_max">'<tt>llvm.atomic.load.max.*</tt>' Intrinsic</a><br>
				6180	<a name="int_atomic_load_min">'<tt>llvm.atomic.load.min.*</tt>' Intrinsic</a><br>
				6181	<a name="int_atomic_load_umax">'<tt>llvm.atomic.load.umax.*</tt>' Intrinsic</a><br>
				6182	<a name="int_atomic_load_umin">'<tt>llvm.atomic.load.umin.*</tt>' Intrinsic</a><br>
				6183
				6184	</div>
				6185	<div class="doc_text">
				6186	<h5>Syntax:</h5>
				6187	<p>
				6188	These are overloaded intrinsics. You can use <tt>llvm.atomic.load_max</tt>,
				6189	<tt>llvm.atomic.load_min</tt>, <tt>llvm.atomic.load_umax</tt>, and
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6190	<tt>llvm.atomic.load_umin</tt> on any integer bit width and for different
				6191	address spaces. Not all targets
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6192	support all bit widths however.</p>
				6193	<pre>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6194	declare i8 @llvm.atomic.load.max.i8.p0i8( i8* <ptr>, i8 <delta> )
				6195	declare i16 @llvm.atomic.load.max.i16.p0i16( i16* <ptr>, i16 <delta> )
				6196	declare i32 @llvm.atomic.load.max.i32.p0i32( i32* <ptr>, i32 <delta> )
				6197	declare i64 @llvm.atomic.load.max.i64.p0i64( i64* <ptr>, i64 <delta> )
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6198
				6199	</pre>
				6200
				6201	<pre>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6202	declare i8 @llvm.atomic.load.min.i8.p0i8( i8* <ptr>, i8 <delta> )
				6203	declare i16 @llvm.atomic.load.min.i16.p0i16( i16* <ptr>, i16 <delta> )
				6204	declare i32 @llvm.atomic.load.min.i32..p0i32( i32* <ptr>, i32 <delta> )
				6205	declare i64 @llvm.atomic.load.min.i64..p0i64( i64* <ptr>, i64 <delta> )
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6206
				6207	</pre>
				6208
				6209	<pre>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6210	declare i8 @llvm.atomic.load.umax.i8.p0i8( i8* <ptr>, i8 <delta> )
				6211	declare i16 @llvm.atomic.load.umax.i16.p0i16( i16* <ptr>, i16 <delta> )
				6212	declare i32 @llvm.atomic.load.umax.i32.p0i32( i32* <ptr>, i32 <delta> )
				6213	declare i64 @llvm.atomic.load.umax.i64.p0i64( i64* <ptr>, i64 <delta> )
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6214
				6215	</pre>
				6216
				6217	<pre>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6218	declare i8 @llvm.atomic.load.umin.i8..p0i8( i8* <ptr>, i8 <delta> )
				6219	declare i16 @llvm.atomic.load.umin.i16.p0i16( i16* <ptr>, i16 <delta> )
				6220	declare i32 @llvm.atomic.load.umin.i32..p0i32( i32* <ptr>, i32 <delta> )
				6221	declare i64 @llvm.atomic.load.umin.i64..p0i64( i64* <ptr>, i64 <delta> )
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6222
				6223	</pre>
				6224	<h5>Overview:</h5>
				6225	<p>
				6226	These intrinsics takes the signed or unsigned minimum or maximum of
				6227	<tt>delta</tt> and the value stored in memory at <tt>ptr</tt>. It yields the
				6228	original value at <tt>ptr</tt>.
				6229	</p>
				6230	<h5>Arguments:</h5>
				6231	<p>
				6232
				6233	These intrinsics take two arguments, the first a pointer to an integer value
				6234	and the second an integer value. The result is also an integer value. These
				6235	integer types can have any bit width, but they must all have the same bit
				6236	width. The targets may only lower integer representations they support.
				6237	</p>
				6238	<h5>Semantics:</h5>
				6239	<p>
				6240	These intrinsics does a series of operations atomically. They first load the
				6241	value stored at <tt>ptr</tt>. They then do the signed or unsigned min or max
				6242	<tt>delta</tt> and the value, store the result to <tt>ptr</tt>. They yield
				6243	the original value stored at <tt>ptr</tt>.
				6244	</p>
				6245
				6246	<h5>Examples:</h5>
				6247	<pre>
				6248	%ptr = malloc i32
				6249	store i32 7, %ptr
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6250	%result0 = call i32 @llvm.atomic.load.min.i32.p0i32( i32* %ptr, i32 -2 )
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6251	<i>; yields {i32}:result0 = 7</i>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6252	%result1 = call i32 @llvm.atomic.load.max.i32.p0i32( i32* %ptr, i32 8 )
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6253	<i>; yields {i32}:result1 = -2</i>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6254	%result2 = call i32 @llvm.atomic.load.umin.i32.p0i32( i32* %ptr, i32 10 )
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6255	<i>; yields {i32}:result2 = 8</i>
Mon P Wang	2c839d4	2008-07-30 04:36:53 +0000	[diff] [blame]	6256	%result3 = call i32 @llvm.atomic.load.umax.i32.p0i32( i32* %ptr, i32 30 )
Mon P Wang	6a49037	2008-06-25 08:15:39 +0000	[diff] [blame]	6257	<i>; yields {i32}:result3 = 8</i>
				6258	%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = 30</i>
				6259	</pre>
				6260	</div>
Andrew Lenharth	9b254ee	2008-02-16 01:24:58 +0000	[diff] [blame]	6261
				6262	<!-- ======================================================================= -->
				6263	<div class="doc_subsection">
Tanya Lattner	cb1b960	2007-06-15 20:50:54 +0000	[diff] [blame]	6264	<a name="int_general">General Intrinsics</a>
				6265	</div>
				6266
				6267	<div class="doc_text">
				6268	<p> This class of intrinsics is designed to be generic and has
				6269	no specific purpose. </p>
				6270	</div>
				6271
				6272	<!-- _______________________________________________________________________ -->
				6273	<div class="doc_subsubsection">
				6274	<a name="int_var_annotation">'<tt>llvm.var.annotation</tt>' Intrinsic</a>
				6275	</div>
				6276
				6277	<div class="doc_text">
				6278
				6279	<h5>Syntax:</h5>
				6280	<pre>
Tanya Lattner	bed1d4d	2007-06-18 23:42:37 +0000	[diff] [blame]	6281	declare void @llvm.var.annotation(i8* <val>, i8* <str>, i8* <str>, i32 <int> )
Tanya Lattner	cb1b960	2007-06-15 20:50:54 +0000	[diff] [blame]	6282	</pre>
				6283
				6284	<h5>Overview:</h5>
				6285
				6286	<p>
				6287	The '<tt>llvm.var.annotation</tt>' intrinsic
				6288	</p>
				6289
				6290	<h5>Arguments:</h5>
				6291
				6292	<p>
Tanya Lattner	bed1d4d	2007-06-18 23:42:37 +0000	[diff] [blame]	6293	The first argument is a pointer to a value, the second is a pointer to a
				6294	global string, the third is a pointer to a global string which is the source
				6295	file name, and the last argument is the line number.
Tanya Lattner	cb1b960	2007-06-15 20:50:54 +0000	[diff] [blame]	6296	</p>
				6297
				6298	<h5>Semantics:</h5>
				6299
				6300	<p>
Anton Korobeynikov	06cbb65	2008-01-15 22:31:34 +0000	[diff] [blame]	6301	This intrinsic allows annotation of local variables with arbitrary strings.
Tanya Lattner	cb1b960	2007-06-15 20:50:54 +0000	[diff] [blame]	6302	This can be useful for special purpose optimizations that want to look for these
Anton Korobeynikov	06cbb65	2008-01-15 22:31:34 +0000	[diff] [blame]	6303	annotations. These have no other defined use, they are ignored by code
				6304	generation and optimization.
				6305	</p>
Tanya Lattner	cb1b960	2007-06-15 20:50:54 +0000	[diff] [blame]	6306	</div>
				6307
Tanya Lattner	293c037	2007-09-21 22:59:12 +0000	[diff] [blame]	6308	<!-- _______________________________________________________________________ -->
				6309	<div class="doc_subsubsection">
Tanya Lattner	0186a65	2007-09-21 23:57:59 +0000	[diff] [blame]	6310	<a name="int_annotation">'<tt>llvm.annotation.*</tt>' Intrinsic</a>
Tanya Lattner	293c037	2007-09-21 22:59:12 +0000	[diff] [blame]	6311	</div>
				6312
				6313	<div class="doc_text">
				6314
				6315	<h5>Syntax:</h5>
Tanya Lattner	23dbd57	2007-09-21 23:56:27 +0000	[diff] [blame]	6316	<p>This is an overloaded intrinsic. You can use '<tt>llvm.annotation</tt>' on
				6317	any integer bit width.
				6318	</p>
Tanya Lattner	293c037	2007-09-21 22:59:12 +0000	[diff] [blame]	6319	<pre>
Tanya Lattner	cf3e26f	2007-09-22 00:03:01 +0000	[diff] [blame]	6320	declare i8 @llvm.annotation.i8(i8 <val>, i8* <str>, i8* <str>, i32 <int> )
				6321	declare i16 @llvm.annotation.i16(i16 <val>, i8* <str>, i8* <str>, i32 <int> )
				6322	declare i32 @llvm.annotation.i32(i32 <val>, i8* <str>, i8* <str>, i32 <int> )
				6323	declare i64 @llvm.annotation.i64(i64 <val>, i8* <str>, i8* <str>, i32 <int> )
				6324	declare i256 @llvm.annotation.i256(i256 <val>, i8* <str>, i8* <str>, i32 <int> )
Tanya Lattner	293c037	2007-09-21 22:59:12 +0000	[diff] [blame]	6325	</pre>
				6326
				6327	<h5>Overview:</h5>
Tanya Lattner	23dbd57	2007-09-21 23:56:27 +0000	[diff] [blame]	6328
				6329	<p>
				6330	The '<tt>llvm.annotation</tt>' intrinsic.
Tanya Lattner	293c037	2007-09-21 22:59:12 +0000	[diff] [blame]	6331	</p>
				6332
				6333	<h5>Arguments:</h5>
				6334
				6335	<p>
				6336	The first argument is an integer value (result of some expression),
				6337	the second is a pointer to a global string, the third is a pointer to a global
				6338	string which is the source file name, and the last argument is the line number.
Tanya Lattner	23dbd57	2007-09-21 23:56:27 +0000	[diff] [blame]	6339	It returns the value of the first argument.
Tanya Lattner	293c037	2007-09-21 22:59:12 +0000	[diff] [blame]	6340	</p>
				6341
				6342	<h5>Semantics:</h5>
				6343
				6344	<p>
				6345	This intrinsic allows annotations to be put on arbitrary expressions
				6346	with arbitrary strings. This can be useful for special purpose optimizations
				6347	that want to look for these annotations. These have no other defined use, they
				6348	are ignored by code generation and optimization.
				6349	</div>
Jim Laskey	2211f49	2007-03-14 19:31:19 +0000	[diff] [blame]	6350
Anton Korobeynikov	06cbb65	2008-01-15 22:31:34 +0000	[diff] [blame]	6351	<!-- _______________________________________________________________________ -->
				6352	<div class="doc_subsubsection">
				6353	<a name="int_trap">'<tt>llvm.trap</tt>' Intrinsic</a>
				6354	</div>
				6355
				6356	<div class="doc_text">
				6357
				6358	<h5>Syntax:</h5>
				6359	<pre>
				6360	declare void @llvm.trap()
				6361	</pre>
				6362
				6363	<h5>Overview:</h5>
				6364
				6365	<p>
				6366	The '<tt>llvm.trap</tt>' intrinsic
				6367	</p>
				6368
				6369	<h5>Arguments:</h5>
				6370
				6371	<p>
				6372	None
				6373	</p>
				6374
				6375	<h5>Semantics:</h5>
				6376
				6377	<p>
				6378	This intrinsics is lowered to the target dependent trap instruction. If the
				6379	target does not have a trap instruction, this intrinsic will be lowered to the
				6380	call of the abort() function.
				6381	</p>
				6382	</div>
				6383
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	6384	<!-- *********************************************************************** -->
Chris Lattner	2f7c963	2001-06-06 20:29:01 +0000	[diff] [blame]	6385	<hr>
Misha Brukman	c501f55	2004-03-01 17:47:27 +0000	[diff] [blame]	6386	<address>
				6387	<a href="http://jigsaw.w3.org/css-validator/check/referer"><img
				6388	src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
				6389	<a href="http://validator.w3.org/check/referer"><img
Chris Lattner	b8f816e	2008-01-04 04:33:49 +0000	[diff] [blame]	6390	src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!"></a>
Misha Brukman	c501f55	2004-03-01 17:47:27 +0000	[diff] [blame]	6391
				6392	<a href="mailto:sabre@nondot.org">Chris Lattner</a><br>
Reid Spencer	ca05854	2006-03-14 05:39:39 +0000	[diff] [blame]	6393	<a href="http://llvm.org">The LLVM Compiler Infrastructure</a><br>
Misha Brukman	c501f55	2004-03-01 17:47:27 +0000	[diff] [blame]	6394	Last modified: $Date$
				6395	</address>
Chris Lattner	b8f816e	2008-01-04 04:33:49 +0000	[diff] [blame]	6396
Misha Brukman	7630785	2003-11-08 01:05:38 +0000	[diff] [blame]	6397	</body>
				6398	</html>