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Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3	<html>
				4	<head>
				5	<title>LLVM Assembly Language Reference Manual</title>
Reid Spencer	3921c74	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	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	10	<link rel="stylesheet" href="llvm.css" type="text/css">
				11	</head>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	12
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	13	<body>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	14
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	15	<div class="doc_title"> LLVM Language Reference Manual </div>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	16	<ol>
Misha Brukman	9d0919f	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	fa73021	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	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	23	<li><a href="#linkage">Linkage Types</a></li>
Chris Lattner	bad10ee	2005-05-06 22:57:40 +0000	[diff] [blame]	24	<li><a href="#callingconv">Calling Conventions</a></li>
Chris Lattner	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	25	<li><a href="#globalvars">Global Variables</a></li>
Chris Lattner	4e9aba7	2006-01-23 23:23:47 +0000	[diff] [blame]	26	<li><a href="#functionstructure">Functions</a></li>
Anton Korobeynikov	c6c98af	2007-04-29 18:02:48 +0000	[diff] [blame]	27	<li><a href="#aliasstructure">Aliases</a>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	28	<li><a href="#paramattrs">Parameter Attributes</a></li>
Gordon Henriksen	80a75bf	2007-12-10 03:18:06 +0000	[diff] [blame]	29	<li><a href="#gc">Garbage Collector Names</a></li>
Chris Lattner	4e9aba7	2006-01-23 23:23:47 +0000	[diff] [blame]	30	<li><a href="#moduleasm">Module-Level Inline Assembly</a></li>
Reid Spencer	de15194	2007-02-19 23:54:10 +0000	[diff] [blame]	31	<li><a href="#datalayout">Data Layout</a></li>
Chris Lattner	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	32	</ol>
				33	</li>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	34	<li><a href="#typesystem">Type System</a>
				35	<ol>
Chris Lattner	4f69f46	2008-01-04 04:32:38 +0000	[diff] [blame]	36	<li><a href="#t_classifications">Type Classifications</a></li>
Robert Bocchino	7b81c75	2006-02-17 21:18:08 +0000	[diff] [blame]	37	<li><a href="#t_primitive">Primitive Types</a>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	38	<ol>
Chris Lattner	4f69f46	2008-01-04 04:32:38 +0000	[diff] [blame]	39	<li><a href="#t_floating">Floating Point Types</a></li>
				40	<li><a href="#t_void">Void Type</a></li>
				41	<li><a href="#t_label">Label Type</a></li>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	42	</ol>
				43	</li>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	44	<li><a href="#t_derived">Derived Types</a>
				45	<ol>
Chris Lattner	b9488a6	2007-12-18 06:18:21 +0000	[diff] [blame]	46	<li><a href="#t_integer">Integer Type</a></li>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	47	<li><a href="#t_array">Array Type</a></li>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	48	<li><a href="#t_function">Function Type</a></li>
				49	<li><a href="#t_pointer">Pointer Type</a></li>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	50	<li><a href="#t_struct">Structure Type</a></li>
Andrew Lenharth	75e1068	2006-12-08 17:13:00 +0000	[diff] [blame]	51	<li><a href="#t_pstruct">Packed Structure Type</a></li>
Reid Spencer	485bad1	2007-02-15 03:07:05 +0000	[diff] [blame]	52	<li><a href="#t_vector">Vector Type</a></li>
Chris Lattner	69c11bb	2005-04-25 17:34:15 +0000	[diff] [blame]	53	<li><a href="#t_opaque">Opaque Type</a></li>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	54	</ol>
				55	</li>
				56	</ol>
				57	</li>
Chris Lattner	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	58	<li><a href="#constants">Constants</a>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	59	<ol>
				60	<li><a href="#simpleconstants">Simple Constants</a>
				61	<li><a href="#aggregateconstants">Aggregate Constants</a>
				62	<li><a href="#globalconstants">Global Variable and Function Addresses</a>
				63	<li><a href="#undefvalues">Undefined Values</a>
				64	<li><a href="#constantexprs">Constant Expressions</a>
				65	</ol>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	66	</li>
Chris Lattner	e87d653	2006-01-25 23:47:57 +0000	[diff] [blame]	67	<li><a href="#othervalues">Other Values</a>
				68	<ol>
				69	<li><a href="#inlineasm">Inline Assembler Expressions</a>
				70	</ol>
				71	</li>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	72	<li><a href="#instref">Instruction Reference</a>
				73	<ol>
				74	<li><a href="#terminators">Terminator Instructions</a>
				75	<ol>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	76	<li><a href="#i_ret">'<tt>ret</tt>' Instruction</a></li>
				77	<li><a href="#i_br">'<tt>br</tt>' Instruction</a></li>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	78	<li><a href="#i_switch">'<tt>switch</tt>' Instruction</a></li>
				79	<li><a href="#i_invoke">'<tt>invoke</tt>' Instruction</a></li>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	80	<li><a href="#i_unwind">'<tt>unwind</tt>' Instruction</a></li>
Chris Lattner	35eca58	2004-10-16 18:04:13 +0000	[diff] [blame]	81	<li><a href="#i_unreachable">'<tt>unreachable</tt>' Instruction</a></li>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	82	</ol>
				83	</li>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	84	<li><a href="#binaryops">Binary Operations</a>
				85	<ol>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	86	<li><a href="#i_add">'<tt>add</tt>' Instruction</a></li>
				87	<li><a href="#i_sub">'<tt>sub</tt>' Instruction</a></li>
				88	<li><a href="#i_mul">'<tt>mul</tt>' Instruction</a></li>
Reid Spencer	1628cec	2006-10-26 06:15:43 +0000	[diff] [blame]	89	<li><a href="#i_udiv">'<tt>udiv</tt>' Instruction</a></li>
				90	<li><a href="#i_sdiv">'<tt>sdiv</tt>' Instruction</a></li>
				91	<li><a href="#i_fdiv">'<tt>fdiv</tt>' Instruction</a></li>
Reid Spencer	0a783f7	2006-11-02 01:53:59 +0000	[diff] [blame]	92	<li><a href="#i_urem">'<tt>urem</tt>' Instruction</a></li>
				93	<li><a href="#i_srem">'<tt>srem</tt>' Instruction</a></li>
				94	<li><a href="#i_frem">'<tt>frem</tt>' Instruction</a></li>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	95	</ol>
				96	</li>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	97	<li><a href="#bitwiseops">Bitwise Binary Operations</a>
				98	<ol>
Reid Spencer	8e11bf8	2007-02-02 13:57:07 +0000	[diff] [blame]	99	<li><a href="#i_shl">'<tt>shl</tt>' Instruction</a></li>
				100	<li><a href="#i_lshr">'<tt>lshr</tt>' Instruction</a></li>
				101	<li><a href="#i_ashr">'<tt>ashr</tt>' Instruction</a></li>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	102	<li><a href="#i_and">'<tt>and</tt>' Instruction</a></li>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	103	<li><a href="#i_or">'<tt>or</tt>' Instruction</a></li>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	104	<li><a href="#i_xor">'<tt>xor</tt>' Instruction</a></li>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	105	</ol>
				106	</li>
Chris Lattner	3df241e	2006-04-08 23:07:04 +0000	[diff] [blame]	107	<li><a href="#vectorops">Vector Operations</a>
				108	<ol>
				109	<li><a href="#i_extractelement">'<tt>extractelement</tt>' Instruction</a></li>
				110	<li><a href="#i_insertelement">'<tt>insertelement</tt>' Instruction</a></li>
				111	<li><a href="#i_shufflevector">'<tt>shufflevector</tt>' Instruction</a></li>
Chris Lattner	3df241e	2006-04-08 23:07:04 +0000	[diff] [blame]	112	</ol>
				113	</li>
Dan Gohman	a334d5f	2008-05-12 23:51:09 +0000	[diff] [blame]	114	<li><a href="#aggregateops">Aggregate Operations</a>
				115	<ol>
				116	<li><a href="#i_extractvalue">'<tt>extractvalue</tt>' Instruction</a></li>
				117	<li><a href="#i_insertvalue">'<tt>insertvalue</tt>' Instruction</a></li>
				118	</ol>
				119	</li>
Chris Lattner	884a970	2006-08-15 00:45:58 +0000	[diff] [blame]	120	<li><a href="#memoryops">Memory Access and Addressing Operations</a>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	121	<ol>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	122	<li><a href="#i_malloc">'<tt>malloc</tt>' Instruction</a></li>
				123	<li><a href="#i_free">'<tt>free</tt>' Instruction</a></li>
				124	<li><a href="#i_alloca">'<tt>alloca</tt>' Instruction</a></li>
Robert Bocchino	7b81c75	2006-02-17 21:18:08 +0000	[diff] [blame]	125	<li><a href="#i_load">'<tt>load</tt>' Instruction</a></li>
				126	<li><a href="#i_store">'<tt>store</tt>' Instruction</a></li>
				127	<li><a href="#i_getelementptr">'<tt>getelementptr</tt>' Instruction</a></li>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	128	</ol>
				129	</li>
Reid Spencer	2fd21e6	2006-11-08 01:18:52 +0000	[diff] [blame]	130	<li><a href="#convertops">Conversion Operations</a>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	131	<ol>
				132	<li><a href="#i_trunc">'<tt>trunc .. to</tt>' Instruction</a></li>
				133	<li><a href="#i_zext">'<tt>zext .. to</tt>' Instruction</a></li>
				134	<li><a href="#i_sext">'<tt>sext .. to</tt>' Instruction</a></li>
				135	<li><a href="#i_fptrunc">'<tt>fptrunc .. to</tt>' Instruction</a></li>
				136	<li><a href="#i_fpext">'<tt>fpext .. to</tt>' Instruction</a></li>
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	137	<li><a href="#i_fptoui">'<tt>fptoui .. to</tt>' Instruction</a></li>
				138	<li><a href="#i_fptosi">'<tt>fptosi .. to</tt>' Instruction</a></li>
				139	<li><a href="#i_uitofp">'<tt>uitofp .. to</tt>' Instruction</a></li>
				140	<li><a href="#i_sitofp">'<tt>sitofp .. to</tt>' Instruction</a></li>
Reid Spencer	7267925	2006-11-11 21:00:47 +0000	[diff] [blame]	141	<li><a href="#i_ptrtoint">'<tt>ptrtoint .. to</tt>' Instruction</a></li>
				142	<li><a href="#i_inttoptr">'<tt>inttoptr .. to</tt>' Instruction</a></li>
Reid Spencer	5c0ef47	2006-11-11 23:08:07 +0000	[diff] [blame]	143	<li><a href="#i_bitcast">'<tt>bitcast .. to</tt>' Instruction</a></li>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	144	</ol>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	145	<li><a href="#otherops">Other Operations</a>
				146	<ol>
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	147	<li><a href="#i_icmp">'<tt>icmp</tt>' Instruction</a></li>
				148	<li><a href="#i_fcmp">'<tt>fcmp</tt>' Instruction</a></li>
Nate Begeman	ac80ade	2008-05-12 19:01:56 +0000	[diff] [blame]	149	<li><a href="#i_vicmp">'<tt>vicmp</tt>' Instruction</a></li>
				150	<li><a href="#i_vfcmp">'<tt>vfcmp</tt>' Instruction</a></li>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	151	<li><a href="#i_phi">'<tt>phi</tt>' Instruction</a></li>
Chris Lattner	cc37aae	2004-03-12 05:50:16 +0000	[diff] [blame]	152	<li><a href="#i_select">'<tt>select</tt>' Instruction</a></li>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	153	<li><a href="#i_call">'<tt>call</tt>' Instruction</a></li>
Chris Lattner	fb6977d	2006-01-13 23:26:01 +0000	[diff] [blame]	154	<li><a href="#i_va_arg">'<tt>va_arg</tt>' Instruction</a></li>
Devang Patel	c3fc6df	2008-03-10 20:49:15 +0000	[diff] [blame]	155	<li><a href="#i_getresult">'<tt>getresult</tt>' Instruction</a></li>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	156	</ol>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	157	</li>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	158	</ol>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	159	</li>
Chris Lattner	d9ad5b3	2003-05-08 04:57:36 +0000	[diff] [blame]	160	<li><a href="#intrinsics">Intrinsic Functions</a>
Chris Lattner	d9ad5b3	2003-05-08 04:57:36 +0000	[diff] [blame]	161	<ol>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	162	<li><a href="#int_varargs">Variable Argument Handling Intrinsics</a>
				163	<ol>
Reid Spencer	a3e435f	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	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	167	</ol>
				168	</li>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	169	<li><a href="#int_gc">Accurate Garbage Collection Intrinsics</a>
				170	<ol>
Reid Spencer	a3e435f	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	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	174	</ol>
				175	</li>
Chris Lattner	1061064	2004-02-14 04:08:35 +0000	[diff] [blame]	176	<li><a href="#int_codegen">Code Generator Intrinsics</a>
				177	<ol>
Reid Spencer	a3e435f	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	7123e27	2004-04-09 16:43:20 +0000	[diff] [blame]	185	</ol>
				186	</li>
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	187	<li><a href="#int_libc">Standard C Library Intrinsics</a>
				188	<ol>
Reid Spencer	a3e435f	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	91c284c	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	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	197	</ol>
				198	</li>
Nate Begeman	7e36c47	2006-01-13 23:26:38 +0000	[diff] [blame]	199	<li><a href="#int_manip">Bit Manipulation Intrinsics</a>
Andrew Lenharth	ec370fd	2005-05-03 18:01:48 +0000	[diff] [blame]	200	<ol>
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	201	<li><a href="#int_bswap">'<tt>llvm.bswap.*</tt>' Intrinsics</a></li>
Chris Lattner	8a886be	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	f86037f	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	ec370fd	2005-05-03 18:01:48 +0000	[diff] [blame]	207	</ol>
				208	</li>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	209	<li><a href="#int_debugger">Debugger intrinsics</a></li>
Jim Laskey	dd4ef1b	2007-03-14 19:31:19 +0000	[diff] [blame]	210	<li><a href="#int_eh">Exception Handling intrinsics</a></li>
Duncan Sands	f7331b3	2007-09-11 14:10:23 +0000	[diff] [blame]	211	<li><a href="#int_trampoline">Trampoline Intrinsic</a>
Duncan Sands	36397f5	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	36397f5	2007-07-27 12:58:54 +0000	[diff] [blame]	214	</ol>
				215	</li>
Andrew Lenharth	22c5c1b	2008-02-16 01:24:58 +0000	[diff] [blame]	216	<li><a href="#int_atomics">Atomic intrinsics</a>
				217	<ol>
Andrew Lenharth	ab0b949	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	2887310	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	ab0b949	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	2887310	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	22c5c1b	2008-02-16 01:24:58 +0000	[diff] [blame]	231	</ol>
				232	</li>
Reid Spencer	2067764	2007-07-20 19:59:11 +0000	[diff] [blame]	233	<li><a href="#int_general">General intrinsics</a>
Tanya Lattner	6d806e9	2007-06-15 20:50:54 +0000	[diff] [blame]	234	<ol>
Reid Spencer	2067764	2007-07-20 19:59:11 +0000	[diff] [blame]	235	<li><a href="#int_var_annotation">
Tanya Lattner	91d0b88	2007-09-22 00:01:26 +0000	[diff] [blame]	236	<tt>llvm.var.annotation</tt>' Intrinsic</a></li>
Tanya Lattner	b636788	2007-09-21 22:59:12 +0000	[diff] [blame]	237	<li><a href="#int_annotation">
Tanya Lattner	91d0b88	2007-09-22 00:01:26 +0000	[diff] [blame]	238	<tt>llvm.annotation.*</tt>' Intrinsic</a></li>
Anton Korobeynikov	4cb8618	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	b636788	2007-09-21 22:59:12 +0000	[diff] [blame]	241	</ol>
Tanya Lattner	6d806e9	2007-06-15 20:50:54 +0000	[diff] [blame]	242	</li>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	243	</ol>
				244	</li>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	245	</ol>
Chris Lattner	d792391	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	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	250	</div>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	251
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	252	<!-- *********************************************************************** -->
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	253	<div class="doc_section"> <a name="abstract">Abstract </a></div>
				254	<!-- *********************************************************************** -->
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	255
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	256	<div class="doc_text">
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	257	<p>This document is a reference manual for the LLVM assembly language.
Bill Wendling	837f39b	2008-08-05 22:29:16 +0000	[diff] [blame]	258	LLVM is a Static Single Assignment (SSA) based representation that provides
Chris Lattner	d3eda89	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	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	261	representation used throughout all phases of the LLVM compilation
				262	strategy.</p>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	263	</div>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	264
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	265	<!-- *********************************************************************** -->
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	266	<div class="doc_section"> <a name="introduction">Introduction</a> </div>
				267	<!-- *********************************************************************** -->
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	268
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	269	<div class="doc_text">
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	270
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	271	<p>The LLVM code representation is designed to be used in three
Gabor Greif	04367bf	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	261efe9	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	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	280
John Criswell	c1f786c	2005-05-13 22:25:59 +0000	[diff] [blame]	281	<p>The LLVM representation aims to be light-weight and low-level
Chris Lattner	261efe9	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	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	291
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	292	</div>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	293
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	294	<!-- _______________________________________________________________________ -->
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	295	<div class="doc_subsubsection"> <a name="wellformed">Well-Formedness</a> </div>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	296
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	297	<div class="doc_text">
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	298
Chris Lattner	261efe9	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	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	303
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	304	<div class="doc_code">
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	305	<pre>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	306	%x = <a href="#i_add">add</a> i32 1, %x
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	307	</pre>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	308	</div>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	309
Chris Lattner	261efe9	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	c1f786c	2005-05-13 22:25:59 +0000	[diff] [blame]	313	automatically run by the parser after parsing input assembly and by
Gabor Greif	04367bf	2007-07-06 22:07:22 +0000	[diff] [blame]	314	the optimizer before it outputs bitcode. The violations pointed out
Chris Lattner	261efe9	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	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	317	</div>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	318
Chris Lattner	cc68939	2007-10-03 17:34:29 +0000	[diff] [blame]	319	<!-- Describe the typesetting conventions here. -->
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	320
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	321	<!-- *********************************************************************** -->
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	322	<div class="doc_section"> <a name="identifiers">Identifiers</a> </div>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	323	<!-- *********************************************************************** -->
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	324
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	325	<div class="doc_text">
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	326
Reid Spencer	2c45228	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	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	331
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	332	<ol>
Reid Spencer	2c45228	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	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	336	Identifiers which require other characters in their names can be surrounded
Reid Spencer	2c45228	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	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	339
Reid Spencer	2c45228	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	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	342
Reid Spencer	cc16dc3	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	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	345	</ol>
Chris Lattner	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	346
Reid Spencer	2c45228	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	e5d947b	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	261efe9	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	5c0ef47	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	ca86e16	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	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	359	and others. These reserved words cannot conflict with variable names, because
Reid Spencer	2c45228	2007-08-07 14:34:28 +0000	[diff] [blame]	360	none of them start with a prefix character ('%' or '@').</p>
Chris Lattner	e5d947b	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	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	365	<p>The easy way:</p>
Chris Lattner	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	366
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	367	<div class="doc_code">
Chris Lattner	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	368	<pre>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	369	%result = <a href="#i_mul">mul</a> i32 %X, 8
Chris Lattner	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	370	</pre>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	371	</div>
Chris Lattner	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	372
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	373	<p>After strength reduction:</p>
Chris Lattner	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	374
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	375	<div class="doc_code">
Chris Lattner	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	376	<pre>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	377	%result = <a href="#i_shl">shl</a> i32 %X, i8 3
Chris Lattner	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	378	</pre>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	379	</div>
Chris Lattner	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	380
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	381	<p>And the hard way:</p>
Chris Lattner	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	382
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	383	<div class="doc_code">
Chris Lattner	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	384	<pre>
Bill Wendling	2f7a8b0	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	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	388	</pre>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	389	</div>
Chris Lattner	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	390
Chris Lattner	261efe9	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	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	393
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	394	<ol>
Chris Lattner	e5d947b	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	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	402	<li>Unnamed temporaries are numbered sequentially</li>
Chris Lattner	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	403
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	404	</ol>
Chris Lattner	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	405
John Criswell	e4c57cc	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	e5d947b	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	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	411	</div>
Chris Lattner	fa73021	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	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	430	<div class="doc_code">
Chris Lattner	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	431	<pre><i>; Declare the string constant as a global constant...</i>
Chris Lattner	a89e5f1	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	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	434
				435	<i>; External declaration of the puts function</i>
Chris Lattner	a89e5f1	2007-06-12 17:00:26 +0000	[diff] [blame]	436	<a href="#functionstructure">declare</a> i32 @puts(i8 ) <i>; i32(i8 )* </i>
Chris Lattner	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	437
				438	<i>; Definition of main function</i>
Chris Lattner	a89e5f1	2007-06-12 17:00:26 +0000	[diff] [blame]	439	define i32 @main() { <i>; i32()* </i>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	440	<i>; Convert [13x i8 ]* to i8 *...</i>
Chris Lattner	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	441	%cast210 = <a
Chris Lattner	6c0955b	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	fa73021	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	a89e5f1	2007-06-12 17:00:26 +0000	[diff] [blame]	446	href="#i_call">call</a> i32 @puts(i8 * %cast210) <i>; i32</i>
Chris Lattner	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	447	<a
Bill Wendling	2f7a8b0	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	fa73021	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	e5d947b	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	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	462
Chris Lattner	e5d947b	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	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	475
				476	<dl>
Chris Lattner	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	477
Dale Johannesen	2307a7f	2008-05-23 23:13:41 +0000	[diff] [blame]	478	<dt><tt><b><a name="linkage_internal">internal</a></b></tt>: </dt>
Chris Lattner	e5d947b	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	4887bd8	2007-01-14 06:51:48 +0000	[diff] [blame]	485	'<tt>static</tt>' keyword in C.
Chris Lattner	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	486	</dd>
Chris Lattner	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	487
Chris Lattner	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	488	<dt><tt><b><a name="linkage_linkonce">linkonce</a></b></tt>: </dt>
Chris Lattner	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	489
Chris Lattner	4887bd8	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	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	495	</dd>
Chris Lattner	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	496
Dale Johannesen	2307a7f	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	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	507	<dt><tt><b><a name="linkage_weak">weak</a></b></tt>: </dt>
Chris Lattner	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	508
Dale Johannesen	2307a7f	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	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	513	</dd>
Chris Lattner	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	514
Chris Lattner	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	515	<dt><tt><b><a name="linkage_appending">appending</a></b></tt>: </dt>
Chris Lattner	e5d947b	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	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	522	</dd>
Chris Lattner	e5d947b	2004-12-09 16:36:40 +0000	[diff] [blame]	523
Anton Korobeynikov	7f70559	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	d3eda89	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	7f70559	2007-01-12 19:20:47 +0000	[diff] [blame]	528	</dd>
Anton Korobeynikov	7f70559	2007-01-12 19:20:47 +0000	[diff] [blame]	529
Chris Lattner	fa73021	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	e5d947b	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	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	535	</dd>
Reid Spencer	c891084	2007-04-11 23:49:50 +0000	[diff] [blame]	536	</dl>
Anton Korobeynikov	b74ed07	2006-09-14 18:23:27 +0000	[diff] [blame]	537
Anton Korobeynikov	b74ed07	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	d3eda89	2008-08-05 18:29:16 +0000	[diff] [blame]	541	DLLs (Dynamic Link Libraries).
Anton Korobeynikov	b74ed07	2006-09-14 18:23:27 +0000	[diff] [blame]	542	</p>
				543
Anton Korobeynikov	7f70559	2007-01-12 19:20:47 +0000	[diff] [blame]	544	<dl>
Anton Korobeynikov	b74ed07	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	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	562	</dl>
				563
Anton Korobeynikov	7f70559	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	fa73021	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	ac8d276	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	7f70559	2007-01-12 19:20:47 +0000	[diff] [blame]	572	or <tt>extern_weak</tt>.</p>
Anton Korobeynikov	8b0a8c8	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	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	575	</div>
				576
				577	<!-- ======================================================================= -->
				578	<div class="doc_subsection">
Chris Lattner	bad10ee	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	e4c57cc	2005-05-12 16:52:32 +0000	[diff] [blame]	596	supports varargs function calls and tolerates some mismatch in the declared
Reid Spencer	c28d2bc	2006-12-31 21:30:18 +0000	[diff] [blame]	597	prototype and implemented declaration of the function (as does normal C).
Chris Lattner	bad10ee	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	d3eda89	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	9097d14	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	bad10ee	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	cfe6b37	2005-05-07 01:46:40 +0000	[diff] [blame]	623	<dt><b>"<tt>cc <<em>n</em>></tt>" - Numbered convention</b>:</dt>
Chris Lattner	bad10ee	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	cfe6b37	2005-05-07 01:46:40 +0000	[diff] [blame]	629	</dl>
Chris Lattner	bad10ee	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	8cea37b	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	d3eda89	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	8cea37b	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	6f9896f	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	8cea37b	2007-01-23 12:35:46 +0000	[diff] [blame]	675	</dl>
				676
				677	</div>
				678
				679	<!-- ======================================================================= -->
				680	<div class="doc_subsection">
Chris Lattner	fa73021	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	3689a34	2005-02-12 19:30:21 +0000	[diff] [blame]	686	<p>Global variables define regions of memory allocated at compilation time
Chris Lattner	88f6c46	2005-11-12 00:45:07 +0000	[diff] [blame]	687	instead of run-time. Global variables may optionally be initialized, may have
Anton Korobeynikov	8b0a8c8	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	3689a34	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	0ec250c	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	3689a34	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	fa73021	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	284d992	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	d49e18d	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	284d992	2007-12-11 09:31:00 +0000	[diff] [blame]	717
Chris Lattner	88f6c46	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	2cbdc45	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	284d992	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	68027ea	2007-01-14 00:27:09 +0000	[diff] [blame]	729
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	730	<div class="doc_code">
Chris Lattner	68027ea	2007-01-14 00:27:09 +0000	[diff] [blame]	731	<pre>
Christopher Lamb	284d992	2007-12-11 09:31:00 +0000	[diff] [blame]	732	@G = constant float 1.0 addrspace(5), section "foo", align 4
Chris Lattner	68027ea	2007-01-14 00:27:09 +0000	[diff] [blame]	733	</pre>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	734	</div>
Chris Lattner	68027ea	2007-01-14 00:27:09 +0000	[diff] [blame]	735
Chris Lattner	fa73021	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	ca86e16	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	8cea37b	2007-01-23 12:35:46 +0000	[diff] [blame]	748	<a href="#visibility">visibility style</a>, an optional
Reid Spencer	ca86e16	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
Anton Korobeynikov	8cea37b	2007-01-23 12:35:46 +0000	[diff] [blame]	752	<a href="#paramattrs">parameter attributes</a>), an optional section, an
Gordon Henriksen	e754abe	2007-12-10 03:30:21 +0000	[diff] [blame]	753	optional alignment, an optional <a href="#gc">garbage collector name</a>, an
Gordon Henriksen	80a75bf	2007-12-10 03:18:06 +0000	[diff] [blame]	754	opening curly brace, a list of basic blocks, and a closing curly brace.
Anton Korobeynikov	8cea37b	2007-01-23 12:35:46 +0000	[diff] [blame]	755
				756	LLVM function declarations consist of the "<tt>declare</tt>" keyword, an
				757	optional <a href="#linkage">linkage type</a>, an optional
				758	<a href="#visibility">visibility style</a>, an optional
				759	<a href="#callingconv">calling convention</a>, a return type, an optional
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	760	<a href="#paramattrs">parameter attribute</a> for the return type, a function
Gordon Henriksen	80a75bf	2007-12-10 03:18:06 +0000	[diff] [blame]	761	name, a possibly empty list of arguments, an optional alignment, and an optional
Gordon Henriksen	e754abe	2007-12-10 03:30:21 +0000	[diff] [blame]	762	<a href="#gc">garbage collector name</a>.</p>
Chris Lattner	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	763
Chris Lattner	d3eda89	2008-08-05 18:29:16 +0000	[diff] [blame]	764	<p>A function definition contains a list of basic blocks, forming the CFG
				765	(Control Flow Graph) for
Chris Lattner	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	766	the function. Each basic block may optionally start with a label (giving the
				767	basic block a symbol table entry), contains a list of instructions, and ends
				768	with a <a href="#terminators">terminator</a> instruction (such as a branch or
				769	function return).</p>
				770
Chris Lattner	4a3c901	2007-06-08 16:52:14 +0000	[diff] [blame]	771	<p>The first basic block in a function is special in two ways: it is immediately
Chris Lattner	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	772	executed on entrance to the function, and it is not allowed to have predecessor
				773	basic blocks (i.e. there can not be any branches to the entry block of a
				774	function). Because the block can have no predecessors, it also cannot have any
				775	<a href="#i_phi">PHI nodes</a>.</p>
				776
Chris Lattner	88f6c46	2005-11-12 00:45:07 +0000	[diff] [blame]	777	<p>LLVM allows an explicit section to be specified for functions. If the target
				778	supports it, it will emit functions to the section specified.</p>
				779
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	780	<p>An explicit alignment may be specified for a function. If not present, or if
				781	the alignment is set to zero, the alignment of the function is set by the target
				782	to whatever it feels convenient. If an explicit alignment is specified, the
				783	function is forced to have at least that much alignment. All alignments must be
				784	a power of 2.</p>
				785
Chris Lattner	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	786	</div>
				787
Anton Korobeynikov	8b0a8c8	2007-04-25 14:27:10 +0000	[diff] [blame]	788
				789	<!-- ======================================================================= -->
				790	<div class="doc_subsection">
				791	<a name="aliasstructure">Aliases</a>
				792	</div>
				793	<div class="doc_text">
				794	<p>Aliases act as "second name" for the aliasee value (which can be either
Anton Korobeynikov	726d45c	2008-03-22 08:36:14 +0000	[diff] [blame]	795	function, global variable, another alias or bitcast of global value). Aliases
				796	may have an optional <a href="#linkage">linkage type</a>, and an
Anton Korobeynikov	8b0a8c8	2007-04-25 14:27:10 +0000	[diff] [blame]	797	optional <a href="#visibility">visibility style</a>.</p>
				798
				799	<h5>Syntax:</h5>
				800
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	801	<div class="doc_code">
Bill Wendling	aac388b	2007-05-29 09:42:13 +0000	[diff] [blame]	802	<pre>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	803	@<Name> = [Linkage] [Visibility] alias <AliaseeTy> @<Aliasee>
Bill Wendling	aac388b	2007-05-29 09:42:13 +0000	[diff] [blame]	804	</pre>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	805	</div>
Anton Korobeynikov	8b0a8c8	2007-04-25 14:27:10 +0000	[diff] [blame]	806
				807	</div>
				808
				809
				810
Chris Lattner	4e9aba7	2006-01-23 23:23:47 +0000	[diff] [blame]	811	<!-- ======================================================================= -->
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	812	<div class="doc_subsection"><a name="paramattrs">Parameter Attributes</a></div>
				813	<div class="doc_text">
				814	<p>The return type and each parameter of a function type may have a set of
				815	<i>parameter attributes</i> associated with them. Parameter attributes are
				816	used to communicate additional information about the result or parameters of
Duncan Sands	dc02467	2007-11-27 13:23:08 +0000	[diff] [blame]	817	a function. Parameter attributes are considered to be part of the function,
				818	not of the function type, so functions with different parameter attributes
				819	can have the same function type.</p>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	820
Reid Spencer	950e9f8	2007-01-15 18:27:39 +0000	[diff] [blame]	821	<p>Parameter attributes are simple keywords that follow the type specified. If
				822	multiple parameter attributes are needed, they are space separated. For
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	823	example:</p>
				824
				825	<div class="doc_code">
				826	<pre>
Duncan Sands	dc02467	2007-11-27 13:23:08 +0000	[diff] [blame]	827	declare i32 @printf(i8* noalias , ...) nounwind
				828	declare i32 @atoi(i8*) nounwind readonly
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	829	</pre>
				830	</div>
				831
Duncan Sands	dc02467	2007-11-27 13:23:08 +0000	[diff] [blame]	832	<p>Note that any attributes for the function result (<tt>nounwind</tt>,
				833	<tt>readonly</tt>) come immediately after the argument list.</p>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	834
Anton Korobeynikov	7f70559	2007-01-12 19:20:47 +0000	[diff] [blame]	835	<p>Currently, only the following parameter attributes are defined:</p>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	836	<dl>
Reid Spencer	9445e9a	2007-07-19 23:13:04 +0000	[diff] [blame]	837	<dt><tt>zeroext</tt></dt>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	838	<dd>This indicates that the parameter should be zero extended just before
				839	a call to this function.</dd>
Chris Lattner	47507de	2008-01-11 06:20:47 +0000	[diff] [blame]	840
Reid Spencer	9445e9a	2007-07-19 23:13:04 +0000	[diff] [blame]	841	<dt><tt>signext</tt></dt>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	842	<dd>This indicates that the parameter should be sign extended just before
				843	a call to this function.</dd>
Chris Lattner	47507de	2008-01-11 06:20:47 +0000	[diff] [blame]	844
Anton Korobeynikov	34d6dea	2007-01-28 14:30:45 +0000	[diff] [blame]	845	<dt><tt>inreg</tt></dt>
				846	<dd>This indicates that the parameter should be placed in register (if
Anton Korobeynikov	66a8c8c	2007-01-28 15:27:21 +0000	[diff] [blame]	847	possible) during assembling function call. Support for this attribute is
				848	target-specific</dd>
Chris Lattner	47507de	2008-01-11 06:20:47 +0000	[diff] [blame]	849
				850	<dt><tt>byval</tt></dt>
Chris Lattner	0747baa	2008-01-15 04:34:22 +0000	[diff] [blame]	851	<dd>This indicates that the pointer parameter should really be passed by
				852	value to the function. The attribute implies that a hidden copy of the
				853	pointee is made between the caller and the callee, so the callee is unable
Chris Lattner	ebec678	2008-08-05 18:21:08 +0000	[diff] [blame]	854	to modify the value in the callee. This attribute is only valid on LLVM
Chris Lattner	0747baa	2008-01-15 04:34:22 +0000	[diff] [blame]	855	pointer arguments. It is generally used to pass structs and arrays by
				856	value, but is also valid on scalars (even though this is silly).</dd>
Chris Lattner	47507de	2008-01-11 06:20:47 +0000	[diff] [blame]	857
Anton Korobeynikov	34d6dea	2007-01-28 14:30:45 +0000	[diff] [blame]	858	<dt><tt>sret</tt></dt>
Duncan Sands	e26dec6	2008-02-18 04:19:38 +0000	[diff] [blame]	859	<dd>This indicates that the pointer parameter specifies the address of a
				860	structure that is the return value of the function in the source program.
Duncan Sands	b7f0c08	2008-03-17 12:17:41 +0000	[diff] [blame]	861	Loads and stores to the structure are assumed not to trap.
Duncan Sands	e26dec6	2008-02-18 04:19:38 +0000	[diff] [blame]	862	May only be applied to the first parameter.</dd>
Chris Lattner	47507de	2008-01-11 06:20:47 +0000	[diff] [blame]	863
Zhou Sheng	febca34	2007-06-05 05:28:26 +0000	[diff] [blame]	864	<dt><tt>noalias</tt></dt>
Owen Anderson	117bbd3	2008-02-18 04:09:01 +0000	[diff] [blame]	865	<dd>This indicates that the parameter does not alias any global or any other
				866	parameter. The caller is responsible for ensuring that this is the case,
				867	usually by placing the value in a stack allocation.</dd>
Chris Lattner	47507de	2008-01-11 06:20:47 +0000	[diff] [blame]	868
Reid Spencer	2dc5201	2007-03-22 02:18:56 +0000	[diff] [blame]	869	<dt><tt>noreturn</tt></dt>
				870	<dd>This function attribute indicates that the function never returns. This
				871	indicates to LLVM that every call to this function should be treated as if
				872	an <tt>unreachable</tt> instruction immediately followed the call.</dd>
Chris Lattner	47507de	2008-01-11 06:20:47 +0000	[diff] [blame]	873
Reid Spencer	6760612	2007-03-22 02:02:11 +0000	[diff] [blame]	874	<dt><tt>nounwind</tt></dt>
Duncan Sands	b7f0c08	2008-03-17 12:17:41 +0000	[diff] [blame]	875	<dd>This function attribute indicates that no exceptions unwind out of the
				876	function. Usually this is because the function makes no use of exceptions,
				877	but it may also be that the function catches any exceptions thrown when
				878	executing it.</dd>
				879
Duncan Sands	50f19f5	2007-07-27 19:57:41 +0000	[diff] [blame]	880	<dt><tt>nest</tt></dt>
Duncan Sands	0789b8b	2008-07-08 09:27:25 +0000	[diff] [blame]	881	<dd>This indicates that the pointer parameter can be excised using the
Duncan Sands	50f19f5	2007-07-27 19:57:41 +0000	[diff] [blame]	882	<a href="#int_trampoline">trampoline intrinsics</a>.</dd>
Duncan Sands	ed4a2f1	2007-11-22 20:23:04 +0000	[diff] [blame]	883	<dt><tt>readonly</tt></dt>
Duncan Sands	f04d584	2007-11-14 21:14:02 +0000	[diff] [blame]	884	<dd>This function attribute indicates that the function has no side-effects
Duncan Sands	ed4a2f1	2007-11-22 20:23:04 +0000	[diff] [blame]	885	except for producing a return value or throwing an exception. The value
				886	returned must only depend on the function arguments and/or global variables.
				887	It may use values obtained by dereferencing pointers.</dd>
				888	<dt><tt>readnone</tt></dt>
				889	<dd>A <tt>readnone</tt> function has the same restrictions as a <tt>readonly</tt>
Duncan Sands	f04d584	2007-11-14 21:14:02 +0000	[diff] [blame]	890	function, but in addition it is not allowed to dereference any pointer arguments
				891	or global variables.
Anton Korobeynikov	7f70559	2007-01-12 19:20:47 +0000	[diff] [blame]	892	</dl>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	893
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	894	</div>
				895
				896	<!-- ======================================================================= -->
Chris Lattner	4e9aba7	2006-01-23 23:23:47 +0000	[diff] [blame]	897	<div class="doc_subsection">
Gordon Henriksen	80a75bf	2007-12-10 03:18:06 +0000	[diff] [blame]	898	<a name="gc">Garbage Collector Names</a>
				899	</div>
				900
				901	<div class="doc_text">
				902	<p>Each function may specify a garbage collector name, which is simply a
				903	string.</p>
				904
				905	<div class="doc_code"><pre
				906	>define void @f() gc "name" { ...</pre></div>
				907
				908	<p>The compiler declares the supported values of <i>name</i>. Specifying a
				909	collector which will cause the compiler to alter its output in order to support
				910	the named garbage collection algorithm.</p>
				911	</div>
				912
				913	<!-- ======================================================================= -->
				914	<div class="doc_subsection">
Chris Lattner	1eeeb0c	2006-04-08 04:40:53 +0000	[diff] [blame]	915	<a name="moduleasm">Module-Level Inline Assembly</a>
Chris Lattner	4e9aba7	2006-01-23 23:23:47 +0000	[diff] [blame]	916	</div>
				917
				918	<div class="doc_text">
				919	<p>
				920	Modules may contain "module-level inline asm" blocks, which corresponds to the
				921	GCC "file scope inline asm" blocks. These blocks are internally concatenated by
				922	LLVM and treated as a single unit, but may be separated in the .ll file if
				923	desired. The syntax is very simple:
				924	</p>
				925
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	926	<div class="doc_code">
				927	<pre>
				928	module asm "inline asm code goes here"
				929	module asm "more can go here"
				930	</pre>
				931	</div>
Chris Lattner	4e9aba7	2006-01-23 23:23:47 +0000	[diff] [blame]	932
				933	<p>The strings can contain any character by escaping non-printable characters.
				934	The escape sequence used is simply "\xx" where "xx" is the two digit hex code
				935	for the number.
				936	</p>
				937
				938	<p>
				939	The inline asm code is simply printed to the machine code .s file when
				940	assembly code is generated.
				941	</p>
				942	</div>
Chris Lattner	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	943
Reid Spencer	de15194	2007-02-19 23:54:10 +0000	[diff] [blame]	944	<!-- ======================================================================= -->
				945	<div class="doc_subsection">
				946	<a name="datalayout">Data Layout</a>
				947	</div>
				948
				949	<div class="doc_text">
				950	<p>A module may specify a target specific data layout string that specifies how
Reid Spencer	c891084	2007-04-11 23:49:50 +0000	[diff] [blame]	951	data is to be laid out in memory. The syntax for the data layout is simply:</p>
				952	<pre> target datalayout = "<i>layout specification</i>"</pre>
				953	<p>The <i>layout specification</i> consists of a list of specifications
				954	separated by the minus sign character ('-'). Each specification starts with a
				955	letter and may include other information after the letter to define some
				956	aspect of the data layout. The specifications accepted are as follows: </p>
Reid Spencer	de15194	2007-02-19 23:54:10 +0000	[diff] [blame]	957	<dl>
				958	<dt><tt>E</tt></dt>
				959	<dd>Specifies that the target lays out data in big-endian form. That is, the
				960	bits with the most significance have the lowest address location.</dd>
				961	<dt><tt>e</tt></dt>
Chris Lattner	d3eda89	2008-08-05 18:29:16 +0000	[diff] [blame]	962	<dd>Specifies that the target lays out data in little-endian form. That is,
Reid Spencer	de15194	2007-02-19 23:54:10 +0000	[diff] [blame]	963	the bits with the least significance have the lowest address location.</dd>
				964	<dt><tt>p:<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
				965	<dd>This specifies the <i>size</i> of a pointer and its <i>abi</i> and
				966	<i>preferred</i> alignments. All sizes are in bits. Specifying the <i>pref</i>
				967	alignment is optional. If omitted, the preceding <tt>:</tt> should be omitted
				968	too.</dd>
				969	<dt><tt>i<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
				970	<dd>This specifies the alignment for an integer type of a given bit
				971	<i>size</i>. The value of <i>size</i> must be in the range [1,2^23).</dd>
				972	<dt><tt>v<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
				973	<dd>This specifies the alignment for a vector type of a given bit
				974	<i>size</i>.</dd>
				975	<dt><tt>f<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
				976	<dd>This specifies the alignment for a floating point type of a given bit
				977	<i>size</i>. The value of <i>size</i> must be either 32 (float) or 64
				978	(double).</dd>
				979	<dt><tt>a<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
				980	<dd>This specifies the alignment for an aggregate type of a given bit
				981	<i>size</i>.</dd>
				982	</dl>
				983	<p>When constructing the data layout for a given target, LLVM starts with a
				984	default set of specifications which are then (possibly) overriden by the
				985	specifications in the <tt>datalayout</tt> keyword. The default specifications
				986	are given in this list:</p>
				987	<ul>
				988	<li><tt>E</tt> - big endian</li>
				989	<li><tt>p:32:64:64</tt> - 32-bit pointers with 64-bit alignment</li>
				990	<li><tt>i1:8:8</tt> - i1 is 8-bit (byte) aligned</li>
				991	<li><tt>i8:8:8</tt> - i8 is 8-bit (byte) aligned</li>
				992	<li><tt>i16:16:16</tt> - i16 is 16-bit aligned</li>
				993	<li><tt>i32:32:32</tt> - i32 is 32-bit aligned</li>
Chris Lattner	d3eda89	2008-08-05 18:29:16 +0000	[diff] [blame]	994	<li><tt>i64:32:64</tt> - i64 has ABI alignment of 32-bits but preferred
Reid Spencer	de15194	2007-02-19 23:54:10 +0000	[diff] [blame]	995	alignment of 64-bits</li>
				996	<li><tt>f32:32:32</tt> - float is 32-bit aligned</li>
				997	<li><tt>f64:64:64</tt> - double is 64-bit aligned</li>
				998	<li><tt>v64:64:64</tt> - 64-bit vector is 64-bit aligned</li>
				999	<li><tt>v128:128:128</tt> - 128-bit vector is 128-bit aligned</li>
				1000	<li><tt>a0:0:1</tt> - aggregates are 8-bit aligned</li>
				1001	</ul>
Chris Lattner	ebec678	2008-08-05 18:21:08 +0000	[diff] [blame]	1002	<p>When LLVM is determining the alignment for a given type, it uses the
Reid Spencer	de15194	2007-02-19 23:54:10 +0000	[diff] [blame]	1003	following rules:
				1004	<ol>
				1005	<li>If the type sought is an exact match for one of the specifications, that
				1006	specification is used.</li>
				1007	<li>If no match is found, and the type sought is an integer type, then the
				1008	smallest integer type that is larger than the bitwidth of the sought type is
				1009	used. If none of the specifications are larger than the bitwidth then the the
				1010	largest integer type is used. For example, given the default specifications
				1011	above, the i7 type will use the alignment of i8 (next largest) while both
				1012	i65 and i256 will use the alignment of i64 (largest specified).</li>
				1013	<li>If no match is found, and the type sought is a vector type, then the
				1014	largest vector type that is smaller than the sought vector type will be used
				1015	as a fall back. This happens because <128 x double> can be implemented in
				1016	terms of 64 <2 x double>, for example.</li>
				1017	</ol>
				1018	</div>
Chris Lattner	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	1019
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1020	<!-- *********************************************************************** -->
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1021	<div class="doc_section"> <a name="typesystem">Type System</a> </div>
				1022	<!-- *********************************************************************** -->
Chris Lattner	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	1023
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1024	<div class="doc_text">
Chris Lattner	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	1025
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1026	<p>The LLVM type system is one of the most important features of the
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1027	intermediate representation. Being typed enables a number of
Chris Lattner	d3eda89	2008-08-05 18:29:16 +0000	[diff] [blame]	1028	optimizations to be performed on the intermediate representation directly,
				1029	without having to do
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1030	extra analyses on the side before the transformation. A strong type
				1031	system makes it easier to read the generated code and enables novel
				1032	analyses and transformations that are not feasible to perform on normal
				1033	three address code representations.</p>
Chris Lattner	fa73021	2004-12-09 16:11:40 +0000	[diff] [blame]	1034
				1035	</div>
				1036
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1037	<!-- ======================================================================= -->
Chris Lattner	4f69f46	2008-01-04 04:32:38 +0000	[diff] [blame]	1038	<div class="doc_subsection"> <a name="t_classifications">Type
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1039	Classifications</a> </div>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1040	<div class="doc_text">
Chris Lattner	4f69f46	2008-01-04 04:32:38 +0000	[diff] [blame]	1041	<p>The types fall into a few useful
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1042	classifications:</p>
Misha Brukman	daa4cb0	2004-03-01 17:47:27 +0000	[diff] [blame]	1043
				1044	<table border="1" cellspacing="0" cellpadding="4">
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1045	<tbody>
Reid Spencer	d3f876c	2004-11-01 08:19:36 +0000	[diff] [blame]	1046	<tr><th>Classification</th><th>Types</th></tr>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1047	<tr>
Chris Lattner	4f69f46	2008-01-04 04:32:38 +0000	[diff] [blame]	1048	<td><a href="#t_integer">integer</a></td>
Reid Spencer	2b91631	2007-05-16 18:44:01 +0000	[diff] [blame]	1049	<td><tt>i1, i2, i3, ... i8, ... i16, ... i32, ... i64, ... </tt></td>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1050	</tr>
				1051	<tr>
Chris Lattner	4f69f46	2008-01-04 04:32:38 +0000	[diff] [blame]	1052	<td><a href="#t_floating">floating point</a></td>
				1053	<td><tt>float, double, x86_fp80, fp128, ppc_fp128</tt></td>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1054	</tr>
				1055	<tr>
				1056	<td><a name="t_firstclass">first class</a></td>
Chris Lattner	4f69f46	2008-01-04 04:32:38 +0000	[diff] [blame]	1057	<td><a href="#t_integer">integer</a>,
				1058	<a href="#t_floating">floating point</a>,
				1059	<a href="#t_pointer">pointer</a>,
Dan Gohman	0066db6	2008-06-18 18:42:13 +0000	[diff] [blame]	1060	<a href="#t_vector">vector</a>,
Dan Gohman	a334d5f	2008-05-12 23:51:09 +0000	[diff] [blame]	1061	<a href="#t_struct">structure</a>,
				1062	<a href="#t_array">array</a>,
Dan Gohman	ade5faa	2008-05-23 22:50:26 +0000	[diff] [blame]	1063	<a href="#t_label">label</a>.
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	1064	</td>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1065	</tr>
Chris Lattner	4f69f46	2008-01-04 04:32:38 +0000	[diff] [blame]	1066	<tr>
				1067	<td><a href="#t_primitive">primitive</a></td>
				1068	<td><a href="#t_label">label</a>,
				1069	<a href="#t_void">void</a>,
Chris Lattner	4f69f46	2008-01-04 04:32:38 +0000	[diff] [blame]	1070	<a href="#t_floating">floating point</a>.</td>
				1071	</tr>
				1072	<tr>
				1073	<td><a href="#t_derived">derived</a></td>
				1074	<td><a href="#t_integer">integer</a>,
				1075	<a href="#t_array">array</a>,
				1076	<a href="#t_function">function</a>,
				1077	<a href="#t_pointer">pointer</a>,
				1078	<a href="#t_struct">structure</a>,
				1079	<a href="#t_pstruct">packed structure</a>,
				1080	<a href="#t_vector">vector</a>,
				1081	<a href="#t_opaque">opaque</a>.
				1082	</tr>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1083	</tbody>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1084	</table>
Misha Brukman	daa4cb0	2004-03-01 17:47:27 +0000	[diff] [blame]	1085
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1086	<p>The <a href="#t_firstclass">first class</a> types are perhaps the
				1087	most important. Values of these types are the only ones which can be
				1088	produced by instructions, passed as arguments, or used as operands to
Dan Gohman	c4b49eb	2008-05-23 21:53:15 +0000	[diff] [blame]	1089	instructions.</p>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1090	</div>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1091
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1092	<!-- ======================================================================= -->
Chris Lattner	4f69f46	2008-01-04 04:32:38 +0000	[diff] [blame]	1093	<div class="doc_subsection"> <a name="t_primitive">Primitive Types</a> </div>
Chris Lattner	8f8c7b7	2008-01-04 04:34:14 +0000	[diff] [blame]	1094
Chris Lattner	4f69f46	2008-01-04 04:32:38 +0000	[diff] [blame]	1095	<div class="doc_text">
				1096	<p>The primitive types are the fundamental building blocks of the LLVM
				1097	system.</p>
				1098
Chris Lattner	8f8c7b7	2008-01-04 04:34:14 +0000	[diff] [blame]	1099	</div>
				1100
Chris Lattner	4f69f46	2008-01-04 04:32:38 +0000	[diff] [blame]	1101	<!-- _______________________________________________________________________ -->
				1102	<div class="doc_subsubsection"> <a name="t_floating">Floating Point Types</a> </div>
				1103
				1104	<div class="doc_text">
				1105	<table>
				1106	<tbody>
				1107	<tr><th>Type</th><th>Description</th></tr>
				1108	<tr><td><tt>float</tt></td><td>32-bit floating point value</td></tr>
				1109	<tr><td><tt>double</tt></td><td>64-bit floating point value</td></tr>
				1110	<tr><td><tt>fp128</tt></td><td>128-bit floating point value (112-bit mantissa)</td></tr>
				1111	<tr><td><tt>x86_fp80</tt></td><td>80-bit floating point value (X87)</td></tr>
				1112	<tr><td><tt>ppc_fp128</tt></td><td>128-bit floating point value (two 64-bits)</td></tr>
				1113	</tbody>
				1114	</table>
				1115	</div>
				1116
				1117	<!-- _______________________________________________________________________ -->
				1118	<div class="doc_subsubsection"> <a name="t_void">Void Type</a> </div>
				1119
				1120	<div class="doc_text">
				1121	<h5>Overview:</h5>
				1122	<p>The void type does not represent any value and has no size.</p>
				1123
				1124	<h5>Syntax:</h5>
				1125
				1126	<pre>
				1127	void
				1128	</pre>
				1129	</div>
				1130
				1131	<!-- _______________________________________________________________________ -->
				1132	<div class="doc_subsubsection"> <a name="t_label">Label Type</a> </div>
				1133
				1134	<div class="doc_text">
				1135	<h5>Overview:</h5>
				1136	<p>The label type represents code labels.</p>
				1137
				1138	<h5>Syntax:</h5>
				1139
				1140	<pre>
				1141	label
				1142	</pre>
				1143	</div>
				1144
				1145
				1146	<!-- ======================================================================= -->
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1147	<div class="doc_subsection"> <a name="t_derived">Derived Types</a> </div>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1148
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1149	<div class="doc_text">
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1150
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1151	<p>The real power in LLVM comes from the derived types in the system.
				1152	This is what allows a programmer to represent arrays, functions,
				1153	pointers, and other useful types. Note that these derived types may be
				1154	recursive: For example, it is possible to have a two dimensional array.</p>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1155
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1156	</div>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1157
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1158	<!-- _______________________________________________________________________ -->
Reid Spencer	2b91631	2007-05-16 18:44:01 +0000	[diff] [blame]	1159	<div class="doc_subsubsection"> <a name="t_integer">Integer Type</a> </div>
				1160
				1161	<div class="doc_text">
				1162
				1163	<h5>Overview:</h5>
				1164	<p>The integer type is a very simple derived type that simply specifies an
				1165	arbitrary bit width for the integer type desired. Any bit width from 1 bit to
				1166	2^23-1 (about 8 million) can be specified.</p>
				1167
				1168	<h5>Syntax:</h5>
				1169
				1170	<pre>
				1171	iN
				1172	</pre>
				1173
				1174	<p>The number of bits the integer will occupy is specified by the <tt>N</tt>
				1175	value.</p>
				1176
				1177	<h5>Examples:</h5>
				1178	<table class="layout">
Chris Lattner	b9488a6	2007-12-18 06:18:21 +0000	[diff] [blame]	1179	<tbody>
				1180	<tr>
				1181	<td><tt>i1</tt></td>
				1182	<td>a single-bit integer.</td>
				1183	</tr><tr>
				1184	<td><tt>i32</tt></td>
				1185	<td>a 32-bit integer.</td>
				1186	</tr><tr>
				1187	<td><tt>i1942652</tt></td>
				1188	<td>a really big integer of over 1 million bits.</td>
Reid Spencer	2b91631	2007-05-16 18:44:01 +0000	[diff] [blame]	1189	</tr>
Chris Lattner	b9488a6	2007-12-18 06:18:21 +0000	[diff] [blame]	1190	</tbody>
Reid Spencer	2b91631	2007-05-16 18:44:01 +0000	[diff] [blame]	1191	</table>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	1192	</div>
Reid Spencer	2b91631	2007-05-16 18:44:01 +0000	[diff] [blame]	1193
				1194	<!-- _______________________________________________________________________ -->
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1195	<div class="doc_subsubsection"> <a name="t_array">Array Type</a> </div>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1196
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1197	<div class="doc_text">
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1198
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1199	<h5>Overview:</h5>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1200
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1201	<p>The array type is a very simple derived type that arranges elements
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1202	sequentially in memory. The array type requires a size (number of
				1203	elements) and an underlying data type.</p>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1204
Chris Lattner	7faa883	2002-04-14 06:13:44 +0000	[diff] [blame]	1205	<h5>Syntax:</h5>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1206
				1207	<pre>
				1208	[<# elements> x <elementtype>]
				1209	</pre>
				1210
John Criswell	e4c57cc	2005-05-12 16:52:32 +0000	[diff] [blame]	1211	<p>The number of elements is a constant integer value; elementtype may
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1212	be any type with a size.</p>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1213
Chris Lattner	7faa883	2002-04-14 06:13:44 +0000	[diff] [blame]	1214	<h5>Examples:</h5>
Reid Spencer	d3f876c	2004-11-01 08:19:36 +0000	[diff] [blame]	1215	<table class="layout">
				1216	<tr class="layout">
Chris Lattner	23ff1f9	2007-12-19 05:04:11 +0000	[diff] [blame]	1217	<td class="left"><tt>[40 x i32]</tt></td>
				1218	<td class="left">Array of 40 32-bit integer values.</td>
				1219	</tr>
				1220	<tr class="layout">
				1221	<td class="left"><tt>[41 x i32]</tt></td>
				1222	<td class="left">Array of 41 32-bit integer values.</td>
				1223	</tr>
				1224	<tr class="layout">
				1225	<td class="left"><tt>[4 x i8]</tt></td>
				1226	<td class="left">Array of 4 8-bit integer values.</td>
Reid Spencer	d3f876c	2004-11-01 08:19:36 +0000	[diff] [blame]	1227	</tr>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1228	</table>
Reid Spencer	d3f876c	2004-11-01 08:19:36 +0000	[diff] [blame]	1229	<p>Here are some examples of multidimensional arrays:</p>
				1230	<table class="layout">
				1231	<tr class="layout">
Chris Lattner	23ff1f9	2007-12-19 05:04:11 +0000	[diff] [blame]	1232	<td class="left"><tt>[3 x [4 x i32]]</tt></td>
				1233	<td class="left">3x4 array of 32-bit integer values.</td>
				1234	</tr>
				1235	<tr class="layout">
				1236	<td class="left"><tt>[12 x [10 x float]]</tt></td>
				1237	<td class="left">12x10 array of single precision floating point values.</td>
				1238	</tr>
				1239	<tr class="layout">
				1240	<td class="left"><tt>[2 x [3 x [4 x i16]]]</tt></td>
				1241	<td class="left">2x3x4 array of 16-bit integer values.</td>
Reid Spencer	d3f876c	2004-11-01 08:19:36 +0000	[diff] [blame]	1242	</tr>
				1243	</table>
Chris Lattner	e67a951	2005-06-24 17:22:57 +0000	[diff] [blame]	1244
John Criswell	0ec250c	2005-10-24 16:17:18 +0000	[diff] [blame]	1245	<p>Note that 'variable sized arrays' can be implemented in LLVM with a zero
				1246	length array. Normally, accesses past the end of an array are undefined in
Chris Lattner	e67a951	2005-06-24 17:22:57 +0000	[diff] [blame]	1247	LLVM (e.g. it is illegal to access the 5th element of a 3 element array).
				1248	As a special case, however, zero length arrays are recognized to be variable
				1249	length. This allows implementation of 'pascal style arrays' with the LLVM
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	1250	type "{ i32, [0 x float]}", for example.</p>
Chris Lattner	e67a951	2005-06-24 17:22:57 +0000	[diff] [blame]	1251
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1252	</div>
Reid Spencer	d3f876c	2004-11-01 08:19:36 +0000	[diff] [blame]	1253
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1254	<!-- _______________________________________________________________________ -->
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1255	<div class="doc_subsubsection"> <a name="t_function">Function Type</a> </div>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1256	<div class="doc_text">
Chris Lattner	f4cde4e	2008-04-23 04:59:35 +0000	[diff] [blame]	1257
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1258	<h5>Overview:</h5>
Chris Lattner	f4cde4e	2008-04-23 04:59:35 +0000	[diff] [blame]	1259
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1260	<p>The function type can be thought of as a function signature. It
Devang Patel	a582f40	2008-03-24 05:35:41 +0000	[diff] [blame]	1261	consists of a return type and a list of formal parameter types. The
Chris Lattner	f4cde4e	2008-04-23 04:59:35 +0000	[diff] [blame]	1262	return type of a function type is a scalar type, a void type, or a struct type.
Devang Patel	7a3ad1a	2008-03-24 20:52:42 +0000	[diff] [blame]	1263	If the return type is a struct type then all struct elements must be of first
Chris Lattner	f4cde4e	2008-04-23 04:59:35 +0000	[diff] [blame]	1264	class types, and the struct must have at least one element.</p>
Devang Patel	c3fc6df	2008-03-10 20:49:15 +0000	[diff] [blame]	1265
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1266	<h5>Syntax:</h5>
Chris Lattner	f4cde4e	2008-04-23 04:59:35 +0000	[diff] [blame]	1267
				1268	<pre>
				1269	<returntype list> (<parameter list>)
				1270	</pre>
				1271
John Criswell	0ec250c	2005-10-24 16:17:18 +0000	[diff] [blame]	1272	<p>...where '<tt><parameter list></tt>' is a comma-separated list of type
Misha Brukman	c24b758	2004-08-12 20:16:08 +0000	[diff] [blame]	1273	specifiers. Optionally, the parameter list may include a type <tt>...</tt>,
Chris Lattner	27f71f2	2003-09-03 00:41:47 +0000	[diff] [blame]	1274	which indicates that the function takes a variable number of arguments.
				1275	Variable argument functions can access their arguments with the <a
Devang Patel	c3fc6df	2008-03-10 20:49:15 +0000	[diff] [blame]	1276	href="#int_varargs">variable argument handling intrinsic</a> functions.
				1277	'<tt><returntype list></tt>' is a comma-separated list of
				1278	<a href="#t_firstclass">first class</a> type specifiers.</p>
Chris Lattner	f4cde4e	2008-04-23 04:59:35 +0000	[diff] [blame]	1279
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1280	<h5>Examples:</h5>
Reid Spencer	d3f876c	2004-11-01 08:19:36 +0000	[diff] [blame]	1281	<table class="layout">
				1282	<tr class="layout">
Reid Spencer	92f8230	2006-12-31 07:18:34 +0000	[diff] [blame]	1283	<td class="left"><tt>i32 (i32)</tt></td>
				1284	<td class="left">function taking an <tt>i32</tt>, returning an <tt>i32</tt>
Reid Spencer	d3f876c	2004-11-01 08:19:36 +0000	[diff] [blame]	1285	</td>
Reid Spencer	92f8230	2006-12-31 07:18:34 +0000	[diff] [blame]	1286	</tr><tr class="layout">
Reid Spencer	9445e9a	2007-07-19 23:13:04 +0000	[diff] [blame]	1287	<td class="left"><tt>float (i16 signext, i32 )
Reid Spencer	f17a0b7	2006-12-31 07:20:23 +0000	[diff] [blame]	1288	</tt></td>
Reid Spencer	92f8230	2006-12-31 07:18:34 +0000	[diff] [blame]	1289	<td class="left"><a href="#t_pointer">Pointer</a> to a function that takes
				1290	an <tt>i16</tt> that should be sign extended and a
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	1291	<a href="#t_pointer">pointer</a> to <tt>i32</tt>, returning
Reid Spencer	92f8230	2006-12-31 07:18:34 +0000	[diff] [blame]	1292	<tt>float</tt>.
				1293	</td>
				1294	</tr><tr class="layout">
				1295	<td class="left"><tt>i32 (i8*, ...)</tt></td>
				1296	<td class="left">A vararg function that takes at least one
Reid Spencer	a517338	2007-01-04 16:43:23 +0000	[diff] [blame]	1297	<a href="#t_pointer">pointer</a> to <tt>i8 </tt> (char in C),
Reid Spencer	92f8230	2006-12-31 07:18:34 +0000	[diff] [blame]	1298	which returns an integer. This is the signature for <tt>printf</tt> in
				1299	LLVM.
Reid Spencer	d3f876c	2004-11-01 08:19:36 +0000	[diff] [blame]	1300	</td>
Devang Patel	a582f40	2008-03-24 05:35:41 +0000	[diff] [blame]	1301	</tr><tr class="layout">
				1302	<td class="left"><tt>{i32, i32} (i32)</tt></td>
Devang Patel	3a5bff8	2008-03-24 18:10:52 +0000	[diff] [blame]	1303	<td class="left">A function taking an <tt>i32></tt>, returning two
				1304	<tt> i32 </tt> values as an aggregate of type <tt>{ i32, i32 }</tt>
Devang Patel	a582f40	2008-03-24 05:35:41 +0000	[diff] [blame]	1305	</td>
Reid Spencer	d3f876c	2004-11-01 08:19:36 +0000	[diff] [blame]	1306	</tr>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1307	</table>
Misha Brukman	daa4cb0	2004-03-01 17:47:27 +0000	[diff] [blame]	1308
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1309	</div>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1310	<!-- _______________________________________________________________________ -->
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1311	<div class="doc_subsubsection"> <a name="t_struct">Structure Type</a> </div>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1312	<div class="doc_text">
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1313	<h5>Overview:</h5>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1314	<p>The structure type is used to represent a collection of data members
				1315	together in memory. The packing of the field types is defined to match
				1316	the ABI of the underlying processor. The elements of a structure may
				1317	be any type that has a size.</p>
				1318	<p>Structures are accessed using '<tt><a href="#i_load">load</a></tt>
				1319	and '<tt><a href="#i_store">store</a></tt>' by getting a pointer to a
				1320	field with the '<tt><a href="#i_getelementptr">getelementptr</a></tt>'
				1321	instruction.</p>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1322	<h5>Syntax:</h5>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1323	<pre> { <type list> }<br></pre>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1324	<h5>Examples:</h5>
Reid Spencer	d3f876c	2004-11-01 08:19:36 +0000	[diff] [blame]	1325	<table class="layout">
				1326	<tr class="layout">
Jeff Cohen	6f1cc77	2007-04-22 01:17:39 +0000	[diff] [blame]	1327	<td class="left"><tt>{ i32, i32, i32 }</tt></td>
				1328	<td class="left">A triple of three <tt>i32</tt> values</td>
				1329	</tr><tr class="layout">
				1330	<td class="left"><tt>{ float, i32 (i32) * }</tt></td>
				1331	<td class="left">A pair, where the first element is a <tt>float</tt> and the
				1332	second element is a <a href="#t_pointer">pointer</a> to a
				1333	<a href="#t_function">function</a> that takes an <tt>i32</tt>, returning
				1334	an <tt>i32</tt>.</td>
Reid Spencer	d3f876c	2004-11-01 08:19:36 +0000	[diff] [blame]	1335	</tr>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1336	</table>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1337	</div>
Reid Spencer	d3f876c	2004-11-01 08:19:36 +0000	[diff] [blame]	1338
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1339	<!-- _______________________________________________________________________ -->
Andrew Lenharth	75e1068	2006-12-08 17:13:00 +0000	[diff] [blame]	1340	<div class="doc_subsubsection"> <a name="t_pstruct">Packed Structure Type</a>
				1341	</div>
				1342	<div class="doc_text">
				1343	<h5>Overview:</h5>
				1344	<p>The packed structure type is used to represent a collection of data members
				1345	together in memory. There is no padding between fields. Further, the alignment
				1346	of a packed structure is 1 byte. The elements of a packed structure may
				1347	be any type that has a size.</p>
				1348	<p>Structures are accessed using '<tt><a href="#i_load">load</a></tt>
				1349	and '<tt><a href="#i_store">store</a></tt>' by getting a pointer to a
				1350	field with the '<tt><a href="#i_getelementptr">getelementptr</a></tt>'
				1351	instruction.</p>
				1352	<h5>Syntax:</h5>
				1353	<pre> < { <type list> } > <br></pre>
				1354	<h5>Examples:</h5>
				1355	<table class="layout">
				1356	<tr class="layout">
Jeff Cohen	6f1cc77	2007-04-22 01:17:39 +0000	[diff] [blame]	1357	<td class="left"><tt>< { i32, i32, i32 } ></tt></td>
				1358	<td class="left">A triple of three <tt>i32</tt> values</td>
				1359	</tr><tr class="layout">
Chris Lattner	23ff1f9	2007-12-19 05:04:11 +0000	[diff] [blame]	1360	<td class="left"><tt>< { float, i32 (i32)* } ></tt></td>
Jeff Cohen	6f1cc77	2007-04-22 01:17:39 +0000	[diff] [blame]	1361	<td class="left">A pair, where the first element is a <tt>float</tt> and the
				1362	second element is a <a href="#t_pointer">pointer</a> to a
				1363	<a href="#t_function">function</a> that takes an <tt>i32</tt>, returning
				1364	an <tt>i32</tt>.</td>
Andrew Lenharth	75e1068	2006-12-08 17:13:00 +0000	[diff] [blame]	1365	</tr>
				1366	</table>
				1367	</div>
				1368
				1369	<!-- _______________________________________________________________________ -->
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1370	<div class="doc_subsubsection"> <a name="t_pointer">Pointer Type</a> </div>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1371	<div class="doc_text">
Chris Lattner	7faa883	2002-04-14 06:13:44 +0000	[diff] [blame]	1372	<h5>Overview:</h5>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1373	<p>As in many languages, the pointer type represents a pointer or
Christopher Lamb	284d992	2007-12-11 09:31:00 +0000	[diff] [blame]	1374	reference to another object, which must live in memory. Pointer types may have
				1375	an optional address space attribute defining the target-specific numbered
				1376	address space where the pointed-to object resides. The default address space is
				1377	zero.</p>
Chris Lattner	7faa883	2002-04-14 06:13:44 +0000	[diff] [blame]	1378	<h5>Syntax:</h5>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1379	<pre> <type> *<br></pre>
Chris Lattner	7faa883	2002-04-14 06:13:44 +0000	[diff] [blame]	1380	<h5>Examples:</h5>
Reid Spencer	d3f876c	2004-11-01 08:19:36 +0000	[diff] [blame]	1381	<table class="layout">
				1382	<tr class="layout">
Chris Lattner	23ff1f9	2007-12-19 05:04:11 +0000	[diff] [blame]	1383	<td class="left"><tt>[4x i32]*</tt></td>
				1384	<td class="left">A <a href="#t_pointer">pointer</a> to <a
				1385	href="#t_array">array</a> of four <tt>i32</tt> values.</td>
				1386	</tr>
				1387	<tr class="layout">
				1388	<td class="left"><tt>i32 (i32 ) </tt></td>
				1389	<td class="left"> A <a href="#t_pointer">pointer</a> to a <a
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	1390	href="#t_function">function</a> that takes an <tt>i32*</tt>, returning an
Chris Lattner	23ff1f9	2007-12-19 05:04:11 +0000	[diff] [blame]	1391	<tt>i32</tt>.</td>
				1392	</tr>
				1393	<tr class="layout">
				1394	<td class="left"><tt>i32 addrspace(5)*</tt></td>
				1395	<td class="left">A <a href="#t_pointer">pointer</a> to an <tt>i32</tt> value
				1396	that resides in address space #5.</td>
Reid Spencer	d3f876c	2004-11-01 08:19:36 +0000	[diff] [blame]	1397	</tr>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1398	</table>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1399	</div>
Reid Spencer	d3f876c	2004-11-01 08:19:36 +0000	[diff] [blame]	1400
Chris Lattner	a58561b	2004-08-12 19:12:28 +0000	[diff] [blame]	1401	<!-- _______________________________________________________________________ -->
Reid Spencer	485bad1	2007-02-15 03:07:05 +0000	[diff] [blame]	1402	<div class="doc_subsubsection"> <a name="t_vector">Vector Type</a> </div>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1403	<div class="doc_text">
Chris Lattner	69c11bb	2005-04-25 17:34:15 +0000	[diff] [blame]	1404
Chris Lattner	a58561b	2004-08-12 19:12:28 +0000	[diff] [blame]	1405	<h5>Overview:</h5>
Chris Lattner	69c11bb	2005-04-25 17:34:15 +0000	[diff] [blame]	1406
Reid Spencer	485bad1	2007-02-15 03:07:05 +0000	[diff] [blame]	1407	<p>A vector type is a simple derived type that represents a vector
				1408	of elements. Vector types are used when multiple primitive data
Chris Lattner	a58561b	2004-08-12 19:12:28 +0000	[diff] [blame]	1409	are operated in parallel using a single instruction (SIMD).
Reid Spencer	485bad1	2007-02-15 03:07:05 +0000	[diff] [blame]	1410	A vector type requires a size (number of
Chris Lattner	b8d172f	2005-11-10 01:44:22 +0000	[diff] [blame]	1411	elements) and an underlying primitive data type. Vectors must have a power
Reid Spencer	485bad1	2007-02-15 03:07:05 +0000	[diff] [blame]	1412	of two length (1, 2, 4, 8, 16 ...). Vector types are
Chris Lattner	a58561b	2004-08-12 19:12:28 +0000	[diff] [blame]	1413	considered <a href="#t_firstclass">first class</a>.</p>
Chris Lattner	69c11bb	2005-04-25 17:34:15 +0000	[diff] [blame]	1414
Chris Lattner	a58561b	2004-08-12 19:12:28 +0000	[diff] [blame]	1415	<h5>Syntax:</h5>
Chris Lattner	69c11bb	2005-04-25 17:34:15 +0000	[diff] [blame]	1416
				1417	<pre>
				1418	< <# elements> x <elementtype> >
				1419	</pre>
				1420
John Criswell	c1f786c	2005-05-13 22:25:59 +0000	[diff] [blame]	1421	<p>The number of elements is a constant integer value; elementtype may
Chris Lattner	3b19d65	2007-01-15 01:54:13 +0000	[diff] [blame]	1422	be any integer or floating point type.</p>
Chris Lattner	69c11bb	2005-04-25 17:34:15 +0000	[diff] [blame]	1423
Chris Lattner	a58561b	2004-08-12 19:12:28 +0000	[diff] [blame]	1424	<h5>Examples:</h5>
Chris Lattner	69c11bb	2005-04-25 17:34:15 +0000	[diff] [blame]	1425
Reid Spencer	d3f876c	2004-11-01 08:19:36 +0000	[diff] [blame]	1426	<table class="layout">
				1427	<tr class="layout">
Chris Lattner	23ff1f9	2007-12-19 05:04:11 +0000	[diff] [blame]	1428	<td class="left"><tt><4 x i32></tt></td>
				1429	<td class="left">Vector of 4 32-bit integer values.</td>
				1430	</tr>
				1431	<tr class="layout">
				1432	<td class="left"><tt><8 x float></tt></td>
				1433	<td class="left">Vector of 8 32-bit floating-point values.</td>
				1434	</tr>
				1435	<tr class="layout">
				1436	<td class="left"><tt><2 x i64></tt></td>
				1437	<td class="left">Vector of 2 64-bit integer values.</td>
Reid Spencer	d3f876c	2004-11-01 08:19:36 +0000	[diff] [blame]	1438	</tr>
				1439	</table>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1440	</div>
				1441
Chris Lattner	69c11bb	2005-04-25 17:34:15 +0000	[diff] [blame]	1442	<!-- _______________________________________________________________________ -->
				1443	<div class="doc_subsubsection"> <a name="t_opaque">Opaque Type</a> </div>
				1444	<div class="doc_text">
				1445
				1446	<h5>Overview:</h5>
				1447
				1448	<p>Opaque types are used to represent unknown types in the system. This
Gordon Henriksen	8ac04ff	2007-10-14 00:34:53 +0000	[diff] [blame]	1449	corresponds (for example) to the C notion of a forward declared structure type.
Chris Lattner	69c11bb	2005-04-25 17:34:15 +0000	[diff] [blame]	1450	In LLVM, opaque types can eventually be resolved to any type (not just a
				1451	structure type).</p>
				1452
				1453	<h5>Syntax:</h5>
				1454
				1455	<pre>
				1456	opaque
				1457	</pre>
				1458
				1459	<h5>Examples:</h5>
				1460
				1461	<table class="layout">
				1462	<tr class="layout">
Chris Lattner	23ff1f9	2007-12-19 05:04:11 +0000	[diff] [blame]	1463	<td class="left"><tt>opaque</tt></td>
				1464	<td class="left">An opaque type.</td>
Chris Lattner	69c11bb	2005-04-25 17:34:15 +0000	[diff] [blame]	1465	</tr>
				1466	</table>
				1467	</div>
				1468
				1469
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1470	<!-- *********************************************************************** -->
				1471	<div class="doc_section"> <a name="constants">Constants</a> </div>
				1472	<!-- *********************************************************************** -->
				1473
				1474	<div class="doc_text">
				1475
				1476	<p>LLVM has several different basic types of constants. This section describes
				1477	them all and their syntax.</p>
				1478
				1479	</div>
				1480
				1481	<!-- ======================================================================= -->
Reid Spencer	cc16dc3	2004-12-09 18:02:53 +0000	[diff] [blame]	1482	<div class="doc_subsection"><a name="simpleconstants">Simple Constants</a></div>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1483
				1484	<div class="doc_text">
				1485
				1486	<dl>
				1487	<dt><b>Boolean constants</b></dt>
				1488
				1489	<dd>The two strings '<tt>true</tt>' and '<tt>false</tt>' are both valid
Reid Spencer	c78f337	2007-01-12 03:35:51 +0000	[diff] [blame]	1490	constants of the <tt><a href="#t_primitive">i1</a></tt> type.
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1491	</dd>
				1492
				1493	<dt><b>Integer constants</b></dt>
				1494
Reid Spencer	cc16dc3	2004-12-09 18:02:53 +0000	[diff] [blame]	1495	<dd>Standard integers (such as '4') are constants of the <a
Reid Spencer	a517338	2007-01-04 16:43:23 +0000	[diff] [blame]	1496	href="#t_integer">integer</a> type. Negative numbers may be used with
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1497	integer types.
				1498	</dd>
				1499
				1500	<dt><b>Floating point constants</b></dt>
				1501
				1502	<dd>Floating point constants use standard decimal notation (e.g. 123.421),
				1503	exponential notation (e.g. 1.23421e+2), or a more precise hexadecimal
Chris Lattner	a73afe0	2008-04-01 18:45:27 +0000	[diff] [blame]	1504	notation (see below). The assembler requires the exact decimal value of
				1505	a floating-point constant. For example, the assembler accepts 1.25 but
				1506	rejects 1.3 because 1.3 is a repeating decimal in binary. Floating point
				1507	constants must have a <a href="#t_floating">floating point</a> type. </dd>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1508
				1509	<dt><b>Null pointer constants</b></dt>
				1510
John Criswell	9e2485c	2004-12-10 15:51:16 +0000	[diff] [blame]	1511	<dd>The identifier '<tt>null</tt>' is recognized as a null pointer constant
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1512	and must be of <a href="#t_pointer">pointer type</a>.</dd>
				1513
				1514	</dl>
				1515
John Criswell	9e2485c	2004-12-10 15:51:16 +0000	[diff] [blame]	1516	<p>The one non-intuitive notation for constants is the optional hexadecimal form
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1517	of floating point constants. For example, the form '<tt>double
				1518	0x432ff973cafa8000</tt>' is equivalent to (but harder to read than) '<tt>double
				1519	4.5e+15</tt>'. The only time hexadecimal floating point constants are required
Reid Spencer	cc16dc3	2004-12-09 18:02:53 +0000	[diff] [blame]	1520	(and the only time that they are generated by the disassembler) is when a
				1521	floating point constant must be emitted but it cannot be represented as a
				1522	decimal floating point number. For example, NaN's, infinities, and other
				1523	special values are represented in their IEEE hexadecimal format so that
				1524	assembly and disassembly do not cause any bits to change in the constants.</p>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1525
				1526	</div>
				1527
				1528	<!-- ======================================================================= -->
				1529	<div class="doc_subsection"><a name="aggregateconstants">Aggregate Constants</a>
				1530	</div>
				1531
				1532	<div class="doc_text">
Chris Lattner	d4f6b17	2005-03-07 22:13:59 +0000	[diff] [blame]	1533	<p>Aggregate constants arise from aggregation of simple constants
				1534	and smaller aggregate constants.</p>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1535
				1536	<dl>
				1537	<dt><b>Structure constants</b></dt>
				1538
				1539	<dd>Structure constants are represented with notation similar to structure
				1540	type definitions (a comma separated list of elements, surrounded by braces
Chris Lattner	64910ee	2007-12-25 20:34:52 +0000	[diff] [blame]	1541	(<tt>{}</tt>)). For example: "<tt>{ i32 4, float 17.0, i32* @G }</tt>",
				1542	where "<tt>@G</tt>" is declared as "<tt>@G = external global i32</tt>". Structure constants
Chris Lattner	d4f6b17	2005-03-07 22:13:59 +0000	[diff] [blame]	1543	must have <a href="#t_struct">structure type</a>, and the number and
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1544	types of elements must match those specified by the type.
				1545	</dd>
				1546
				1547	<dt><b>Array constants</b></dt>
				1548
				1549	<dd>Array constants are represented with notation similar to array type
				1550	definitions (a comma separated list of elements, surrounded by square brackets
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	1551	(<tt>[]</tt>)). For example: "<tt>[ i32 42, i32 11, i32 74 ]</tt>". Array
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1552	constants must have <a href="#t_array">array type</a>, and the number and
				1553	types of elements must match those specified by the type.
				1554	</dd>
				1555
Reid Spencer	485bad1	2007-02-15 03:07:05 +0000	[diff] [blame]	1556	<dt><b>Vector constants</b></dt>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1557
Reid Spencer	485bad1	2007-02-15 03:07:05 +0000	[diff] [blame]	1558	<dd>Vector constants are represented with notation similar to vector type
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1559	definitions (a comma separated list of elements, surrounded by
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	1560	less-than/greater-than's (<tt><></tt>)). For example: "<tt>< i32 42,
Jeff Cohen	6f1cc77	2007-04-22 01:17:39 +0000	[diff] [blame]	1561	i32 11, i32 74, i32 100 ></tt>". Vector constants must have <a
Reid Spencer	485bad1	2007-02-15 03:07:05 +0000	[diff] [blame]	1562	href="#t_vector">vector type</a>, and the number and types of elements must
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1563	match those specified by the type.
				1564	</dd>
				1565
				1566	<dt><b>Zero initialization</b></dt>
				1567
				1568	<dd>The string '<tt>zeroinitializer</tt>' can be used to zero initialize a
				1569	value to zero of <em>any</em> type, including scalar and aggregate types.
				1570	This is often used to avoid having to print large zero initializers (e.g. for
John Criswell	0ec250c	2005-10-24 16:17:18 +0000	[diff] [blame]	1571	large arrays) and is always exactly equivalent to using explicit zero
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1572	initializers.
				1573	</dd>
				1574	</dl>
				1575
				1576	</div>
				1577
				1578	<!-- ======================================================================= -->
				1579	<div class="doc_subsection">
				1580	<a name="globalconstants">Global Variable and Function Addresses</a>
				1581	</div>
				1582
				1583	<div class="doc_text">
				1584
				1585	<p>The addresses of <a href="#globalvars">global variables</a> and <a
				1586	href="#functionstructure">functions</a> are always implicitly valid (link-time)
John Criswell	9e2485c	2004-12-10 15:51:16 +0000	[diff] [blame]	1587	constants. These constants are explicitly referenced when the <a
				1588	href="#identifiers">identifier for the global</a> is used and always have <a
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1589	href="#t_pointer">pointer</a> type. For example, the following is a legal LLVM
				1590	file:</p>
				1591
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	1592	<div class="doc_code">
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1593	<pre>
Chris Lattner	a18a424	2007-06-06 18:28:13 +0000	[diff] [blame]	1594	@X = global i32 17
				1595	@Y = global i32 42
				1596	@Z = global [2 x i32] [ i32 @X, i32* @Y ]
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1597	</pre>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	1598	</div>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1599
				1600	</div>
				1601
				1602	<!-- ======================================================================= -->
Reid Spencer	2dc45b8	2004-12-09 18:13:12 +0000	[diff] [blame]	1603	<div class="doc_subsection"><a name="undefvalues">Undefined Values</a></div>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1604	<div class="doc_text">
Reid Spencer	2dc45b8	2004-12-09 18:13:12 +0000	[diff] [blame]	1605	<p>The string '<tt>undef</tt>' is recognized as a type-less constant that has
John Criswell	c1f786c	2005-05-13 22:25:59 +0000	[diff] [blame]	1606	no specific value. Undefined values may be of any type and be used anywhere
Reid Spencer	2dc45b8	2004-12-09 18:13:12 +0000	[diff] [blame]	1607	a constant is permitted.</p>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1608
Reid Spencer	2dc45b8	2004-12-09 18:13:12 +0000	[diff] [blame]	1609	<p>Undefined values indicate to the compiler that the program is well defined
				1610	no matter what value is used, giving the compiler more freedom to optimize.
				1611	</p>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1612	</div>
				1613
				1614	<!-- ======================================================================= -->
				1615	<div class="doc_subsection"><a name="constantexprs">Constant Expressions</a>
				1616	</div>
				1617
				1618	<div class="doc_text">
				1619
				1620	<p>Constant expressions are used to allow expressions involving other constants
				1621	to be used as constants. Constant expressions may be of any <a
John Criswell	c1f786c	2005-05-13 22:25:59 +0000	[diff] [blame]	1622	href="#t_firstclass">first class</a> type and may involve any LLVM operation
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1623	that does not have side effects (e.g. load and call are not supported). The
				1624	following is the syntax for constant expressions:</p>
				1625
				1626	<dl>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	1627	<dt><b><tt>trunc ( CST to TYPE )</tt></b></dt>
				1628	<dd>Truncate a constant to another type. The bit size of CST must be larger
Chris Lattner	3b19d65	2007-01-15 01:54:13 +0000	[diff] [blame]	1629	than the bit size of TYPE. Both types must be integers.</dd>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1630
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	1631	<dt><b><tt>zext ( CST to TYPE )</tt></b></dt>
				1632	<dd>Zero extend a constant to another type. The bit size of CST must be
Chris Lattner	3b19d65	2007-01-15 01:54:13 +0000	[diff] [blame]	1633	smaller or equal to the bit size of TYPE. Both types must be integers.</dd>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	1634
				1635	<dt><b><tt>sext ( CST to TYPE )</tt></b></dt>
				1636	<dd>Sign extend a constant to another type. The bit size of CST must be
Chris Lattner	3b19d65	2007-01-15 01:54:13 +0000	[diff] [blame]	1637	smaller or equal to the bit size of TYPE. Both types must be integers.</dd>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	1638
				1639	<dt><b><tt>fptrunc ( CST to TYPE )</tt></b></dt>
				1640	<dd>Truncate a floating point constant to another floating point type. The
				1641	size of CST must be larger than the size of TYPE. Both types must be
				1642	floating point.</dd>
				1643
				1644	<dt><b><tt>fpext ( CST to TYPE )</tt></b></dt>
				1645	<dd>Floating point extend a constant to another type. The size of CST must be
				1646	smaller or equal to the size of TYPE. Both types must be floating point.</dd>
				1647
Reid Spencer	1539a1c	2007-07-31 14:40:14 +0000	[diff] [blame]	1648	<dt><b><tt>fptoui ( CST to TYPE )</tt></b></dt>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	1649	<dd>Convert a floating point constant to the corresponding unsigned integer
Nate Begeman	b348d18	2007-11-17 03:58:34 +0000	[diff] [blame]	1650	constant. TYPE must be a scalar or vector integer type. CST must be of scalar
				1651	or vector floating point type. Both CST and TYPE must be scalars, or vectors
				1652	of the same number of elements. If the value won't fit in the integer type,
				1653	the results are undefined.</dd>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	1654
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	1655	<dt><b><tt>fptosi ( CST to TYPE )</tt></b></dt>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	1656	<dd>Convert a floating point constant to the corresponding signed integer
Nate Begeman	b348d18	2007-11-17 03:58:34 +0000	[diff] [blame]	1657	constant. TYPE must be a scalar or vector integer type. CST must be of scalar
				1658	or vector floating point type. Both CST and TYPE must be scalars, or vectors
				1659	of the same number of elements. If the value won't fit in the integer type,
				1660	the results are undefined.</dd>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	1661
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	1662	<dt><b><tt>uitofp ( CST to TYPE )</tt></b></dt>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	1663	<dd>Convert an unsigned integer constant to the corresponding floating point
Nate Begeman	b348d18	2007-11-17 03:58:34 +0000	[diff] [blame]	1664	constant. TYPE must be a scalar or vector floating point type. CST must be of
				1665	scalar or vector integer type. Both CST and TYPE must be scalars, or vectors
				1666	of the same number of elements. If the value won't fit in the floating point
				1667	type, the results are undefined.</dd>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	1668
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	1669	<dt><b><tt>sitofp ( CST to TYPE )</tt></b></dt>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	1670	<dd>Convert a signed integer constant to the corresponding floating point
Nate Begeman	b348d18	2007-11-17 03:58:34 +0000	[diff] [blame]	1671	constant. TYPE must be a scalar or vector floating point type. CST must be of
				1672	scalar or vector integer type. Both CST and TYPE must be scalars, or vectors
				1673	of the same number of elements. If the value won't fit in the floating point
				1674	type, the results are undefined.</dd>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	1675
Reid Spencer	5c0ef47	2006-11-11 23:08:07 +0000	[diff] [blame]	1676	<dt><b><tt>ptrtoint ( CST to TYPE )</tt></b></dt>
				1677	<dd>Convert a pointer typed constant to the corresponding integer constant
				1678	TYPE must be an integer type. CST must be of pointer type. The CST value is
				1679	zero extended, truncated, or unchanged to make it fit in TYPE.</dd>
				1680
				1681	<dt><b><tt>inttoptr ( CST to TYPE )</tt></b></dt>
				1682	<dd>Convert a integer constant to a pointer constant. TYPE must be a
				1683	pointer type. CST must be of integer type. The CST value is zero extended,
				1684	truncated, or unchanged to make it fit in a pointer size. This one is
				1685	<i>really</i> dangerous!</dd>
				1686
				1687	<dt><b><tt>bitcast ( CST to TYPE )</tt></b></dt>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	1688	<dd>Convert a constant, CST, to another TYPE. The size of CST and TYPE must be
				1689	identical (same number of bits). The conversion is done as if the CST value
				1690	was stored to memory and read back as TYPE. In other words, no bits change
Reid Spencer	5c0ef47	2006-11-11 23:08:07 +0000	[diff] [blame]	1691	with this operator, just the type. This can be used for conversion of
Reid Spencer	485bad1	2007-02-15 03:07:05 +0000	[diff] [blame]	1692	vector types to any other type, as long as they have the same bit width. For
Reid Spencer	5c0ef47	2006-11-11 23:08:07 +0000	[diff] [blame]	1693	pointers it is only valid to cast to another pointer type.
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	1694	</dd>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1695
				1696	<dt><b><tt>getelementptr ( CSTPTR, IDX0, IDX1, ... )</tt></b></dt>
				1697
				1698	<dd>Perform the <a href="#i_getelementptr">getelementptr operation</a> on
				1699	constants. As with the <a href="#i_getelementptr">getelementptr</a>
				1700	instruction, the index list may have zero or more indexes, which are required
				1701	to make sense for the type of "CSTPTR".</dd>
				1702
Robert Bocchino	9fbe145	2006-01-10 19:31:34 +0000	[diff] [blame]	1703	<dt><b><tt>select ( COND, VAL1, VAL2 )</tt></b></dt>
				1704
				1705	<dd>Perform the <a href="#i_select">select operation</a> on
Reid Spencer	01c4259	2006-12-04 19:23:19 +0000	[diff] [blame]	1706	constants.</dd>
				1707
				1708	<dt><b><tt>icmp COND ( VAL1, VAL2 )</tt></b></dt>
				1709	<dd>Performs the <a href="#i_icmp">icmp operation</a> on constants.</dd>
				1710
				1711	<dt><b><tt>fcmp COND ( VAL1, VAL2 )</tt></b></dt>
				1712	<dd>Performs the <a href="#i_fcmp">fcmp operation</a> on constants.</dd>
Robert Bocchino	9fbe145	2006-01-10 19:31:34 +0000	[diff] [blame]	1713
Nate Begeman	ac80ade	2008-05-12 19:01:56 +0000	[diff] [blame]	1714	<dt><b><tt>vicmp COND ( VAL1, VAL2 )</tt></b></dt>
				1715	<dd>Performs the <a href="#i_vicmp">vicmp operation</a> on constants.</dd>
				1716
				1717	<dt><b><tt>vfcmp COND ( VAL1, VAL2 )</tt></b></dt>
				1718	<dd>Performs the <a href="#i_vfcmp">vfcmp operation</a> on constants.</dd>
				1719
Robert Bocchino	9fbe145	2006-01-10 19:31:34 +0000	[diff] [blame]	1720	<dt><b><tt>extractelement ( VAL, IDX )</tt></b></dt>
				1721
				1722	<dd>Perform the <a href="#i_extractelement">extractelement
				1723	operation</a> on constants.
				1724
Robert Bocchino	05ccd70	2006-01-15 20:48:27 +0000	[diff] [blame]	1725	<dt><b><tt>insertelement ( VAL, ELT, IDX )</tt></b></dt>
				1726
				1727	<dd>Perform the <a href="#i_insertelement">insertelement
Reid Spencer	01c4259	2006-12-04 19:23:19 +0000	[diff] [blame]	1728	operation</a> on constants.</dd>
Robert Bocchino	05ccd70	2006-01-15 20:48:27 +0000	[diff] [blame]	1729
Chris Lattner	c198954	2006-04-08 00:13:41 +0000	[diff] [blame]	1730
				1731	<dt><b><tt>shufflevector ( VEC1, VEC2, IDXMASK )</tt></b></dt>
				1732
				1733	<dd>Perform the <a href="#i_shufflevector">shufflevector
Reid Spencer	01c4259	2006-12-04 19:23:19 +0000	[diff] [blame]	1734	operation</a> on constants.</dd>
Chris Lattner	c198954	2006-04-08 00:13:41 +0000	[diff] [blame]	1735
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1736	<dt><b><tt>OPCODE ( LHS, RHS )</tt></b></dt>
				1737
Reid Spencer	2dc45b8	2004-12-09 18:13:12 +0000	[diff] [blame]	1738	<dd>Perform the specified operation of the LHS and RHS constants. OPCODE may
				1739	be any of the <a href="#binaryops">binary</a> or <a href="#bitwiseops">bitwise
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1740	binary</a> operations. The constraints on operands are the same as those for
				1741	the corresponding instruction (e.g. no bitwise operations on floating point
John Criswell	e4c57cc	2005-05-12 16:52:32 +0000	[diff] [blame]	1742	values are allowed).</dd>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1743	</dl>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1744	</div>
Chris Lattner	9ee5d22	2004-03-08 16:49:10 +0000	[diff] [blame]	1745
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1746	<!-- *********************************************************************** -->
Chris Lattner	e87d653	2006-01-25 23:47:57 +0000	[diff] [blame]	1747	<div class="doc_section"> <a name="othervalues">Other Values</a> </div>
				1748	<!-- *********************************************************************** -->
				1749
				1750	<!-- ======================================================================= -->
				1751	<div class="doc_subsection">
				1752	<a name="inlineasm">Inline Assembler Expressions</a>
				1753	</div>
				1754
				1755	<div class="doc_text">
				1756
				1757	<p>
				1758	LLVM supports inline assembler expressions (as opposed to <a href="#moduleasm">
				1759	Module-Level Inline Assembly</a>) through the use of a special value. This
				1760	value represents the inline assembler as a string (containing the instructions
				1761	to emit), a list of operand constraints (stored as a string), and a flag that
				1762	indicates whether or not the inline asm expression has side effects. An example
				1763	inline assembler expression is:
				1764	</p>
				1765
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	1766	<div class="doc_code">
Chris Lattner	e87d653	2006-01-25 23:47:57 +0000	[diff] [blame]	1767	<pre>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	1768	i32 (i32) asm "bswap $0", "=r,r"
Chris Lattner	e87d653	2006-01-25 23:47:57 +0000	[diff] [blame]	1769	</pre>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	1770	</div>
Chris Lattner	e87d653	2006-01-25 23:47:57 +0000	[diff] [blame]	1771
				1772	<p>
				1773	Inline assembler expressions may <b>only</b> be used as the callee operand of
				1774	a <a href="#i_call"><tt>call</tt> instruction</a>. Thus, typically we have:
				1775	</p>
				1776
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	1777	<div class="doc_code">
Chris Lattner	e87d653	2006-01-25 23:47:57 +0000	[diff] [blame]	1778	<pre>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	1779	%X = call i32 asm "<a href="#int_bswap">bswap</a> $0", "=r,r"(i32 %Y)
Chris Lattner	e87d653	2006-01-25 23:47:57 +0000	[diff] [blame]	1780	</pre>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	1781	</div>
Chris Lattner	e87d653	2006-01-25 23:47:57 +0000	[diff] [blame]	1782
				1783	<p>
				1784	Inline asms with side effects not visible in the constraint list must be marked
				1785	as having side effects. This is done through the use of the
				1786	'<tt>sideeffect</tt>' keyword, like so:
				1787	</p>
				1788
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	1789	<div class="doc_code">
Chris Lattner	e87d653	2006-01-25 23:47:57 +0000	[diff] [blame]	1790	<pre>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	1791	call void asm sideeffect "eieio", ""()
Chris Lattner	e87d653	2006-01-25 23:47:57 +0000	[diff] [blame]	1792	</pre>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	1793	</div>
Chris Lattner	e87d653	2006-01-25 23:47:57 +0000	[diff] [blame]	1794
				1795	<p>TODO: The format of the asm and constraints string still need to be
				1796	documented here. Constraints on what can be done (e.g. duplication, moving, etc
				1797	need to be documented).
				1798	</p>
				1799
				1800	</div>
				1801
				1802	<!-- *********************************************************************** -->
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1803	<div class="doc_section"> <a name="instref">Instruction Reference</a> </div>
				1804	<!-- *********************************************************************** -->
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1805
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1806	<div class="doc_text">
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1807
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1808	<p>The LLVM instruction set consists of several different
				1809	classifications of instructions: <a href="#terminators">terminator
John Criswell	c1f786c	2005-05-13 22:25:59 +0000	[diff] [blame]	1810	instructions</a>, <a href="#binaryops">binary instructions</a>,
				1811	<a href="#bitwiseops">bitwise binary instructions</a>, <a
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1812	href="#memoryops">memory instructions</a>, and <a href="#otherops">other
				1813	instructions</a>.</p>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1814
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1815	</div>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1816
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1817	<!-- ======================================================================= -->
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1818	<div class="doc_subsection"> <a name="terminators">Terminator
				1819	Instructions</a> </div>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1820
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1821	<div class="doc_text">
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1822
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1823	<p>As mentioned <a href="#functionstructure">previously</a>, every
				1824	basic block in a program ends with a "Terminator" instruction, which
				1825	indicates which block should be executed after the current block is
				1826	finished. These terminator instructions typically yield a '<tt>void</tt>'
				1827	value: they produce control flow, not values (the one exception being
				1828	the '<a href="#i_invoke"><tt>invoke</tt></a>' instruction).</p>
John Criswell	9e2485c	2004-12-10 15:51:16 +0000	[diff] [blame]	1829	<p>There are six different terminator instructions: the '<a
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1830	href="#i_ret"><tt>ret</tt></a>' instruction, the '<a href="#i_br"><tt>br</tt></a>'
				1831	instruction, the '<a href="#i_switch"><tt>switch</tt></a>' instruction,
Chris Lattner	35eca58	2004-10-16 18:04:13 +0000	[diff] [blame]	1832	the '<a href="#i_invoke"><tt>invoke</tt></a>' instruction, the '<a
				1833	href="#i_unwind"><tt>unwind</tt></a>' instruction, and the '<a
				1834	href="#i_unreachable"><tt>unreachable</tt></a>' instruction.</p>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1835
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1836	</div>
Chris Lattner	c3f5976	2004-12-09 17:30:23 +0000	[diff] [blame]	1837
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1838	<!-- _______________________________________________________________________ -->
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1839	<div class="doc_subsubsection"> <a name="i_ret">'<tt>ret</tt>'
				1840	Instruction</a> </div>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1841	<div class="doc_text">
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1842	<h5>Syntax:</h5>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1843	<pre> ret <type> <value> <i>; Return a value from a non-void function</i>
Chris Lattner	7faa883	2002-04-14 06:13:44 +0000	[diff] [blame]	1844	ret void <i>; Return from void function</i>
Devang Patel	c3fc6df	2008-03-10 20:49:15 +0000	[diff] [blame]	1845	ret <type> <value>, <type> <value> <i>; Return two values from a non-void function </i>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1846	</pre>
Chris Lattner	f4cde4e	2008-04-23 04:59:35 +0000	[diff] [blame]	1847
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1848	<h5>Overview:</h5>
Chris Lattner	f4cde4e	2008-04-23 04:59:35 +0000	[diff] [blame]	1849
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1850	<p>The '<tt>ret</tt>' instruction is used to return control flow (and a
John Criswell	c1f786c	2005-05-13 22:25:59 +0000	[diff] [blame]	1851	value) from a function back to the caller.</p>
John Criswell	4457dc9	2004-04-09 16:48:45 +0000	[diff] [blame]	1852	<p>There are two forms of the '<tt>ret</tt>' instruction: one that
Chris Lattner	f4cde4e	2008-04-23 04:59:35 +0000	[diff] [blame]	1853	returns value(s) and then causes control flow, and one that just causes
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1854	control flow to occur.</p>
Chris Lattner	f4cde4e	2008-04-23 04:59:35 +0000	[diff] [blame]	1855
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1856	<h5>Arguments:</h5>
Chris Lattner	f4cde4e	2008-04-23 04:59:35 +0000	[diff] [blame]	1857
				1858	<p>The '<tt>ret</tt>' instruction may return zero, one or multiple values.
				1859	The type of each return value must be a '<a href="#t_firstclass">first
				1860	class</a>' type. Note that a function is not <a href="#wellformed">well
				1861	formed</a> if there exists a '<tt>ret</tt>' instruction inside of the
				1862	function that returns values that do not match the return type of the
				1863	function.</p>
				1864
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1865	<h5>Semantics:</h5>
Chris Lattner	f4cde4e	2008-04-23 04:59:35 +0000	[diff] [blame]	1866
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1867	<p>When the '<tt>ret</tt>' instruction is executed, control flow
				1868	returns back to the calling function's context. If the caller is a "<a
John Criswell	fa08187	2004-06-25 15:16:57 +0000	[diff] [blame]	1869	href="#i_call"><tt>call</tt></a>" instruction, execution continues at
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1870	the instruction after the call. If the caller was an "<a
				1871	href="#i_invoke"><tt>invoke</tt></a>" instruction, execution continues
John Criswell	e4c57cc	2005-05-12 16:52:32 +0000	[diff] [blame]	1872	at the beginning of the "normal" destination block. If the instruction
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1873	returns a value, that value shall set the call or invoke instruction's
Devang Patel	c3fc6df	2008-03-10 20:49:15 +0000	[diff] [blame]	1874	return value. If the instruction returns multiple values then these
Devang Patel	0dbb4a1	2008-03-11 05:51:59 +0000	[diff] [blame]	1875	values can only be accessed through a '<a href="#i_getresult"><tt>getresult</tt>
				1876	</a>' instruction.</p>
Chris Lattner	f4cde4e	2008-04-23 04:59:35 +0000	[diff] [blame]	1877
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1878	<h5>Example:</h5>
Chris Lattner	f4cde4e	2008-04-23 04:59:35 +0000	[diff] [blame]	1879
				1880	<pre>
				1881	ret i32 5 <i>; Return an integer value of 5</i>
Chris Lattner	7faa883	2002-04-14 06:13:44 +0000	[diff] [blame]	1882	ret void <i>; Return from a void function</i>
Devang Patel	c3fc6df	2008-03-10 20:49:15 +0000	[diff] [blame]	1883	ret i32 4, i8 2 <i>; Return two values 4 and 2 </i>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1884	</pre>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1885	</div>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1886	<!-- _______________________________________________________________________ -->
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1887	<div class="doc_subsubsection"> <a name="i_br">'<tt>br</tt>' Instruction</a> </div>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1888	<div class="doc_text">
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1889	<h5>Syntax:</h5>
Reid Spencer	c78f337	2007-01-12 03:35:51 +0000	[diff] [blame]	1890	<pre> br i1 <cond>, label <iftrue>, label <iffalse><br> br label <dest> <i>; Unconditional branch</i>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1891	</pre>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1892	<h5>Overview:</h5>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1893	<p>The '<tt>br</tt>' instruction is used to cause control flow to
				1894	transfer to a different basic block in the current function. There are
				1895	two forms of this instruction, corresponding to a conditional branch
				1896	and an unconditional branch.</p>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1897	<h5>Arguments:</h5>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1898	<p>The conditional branch form of the '<tt>br</tt>' instruction takes a
Reid Spencer	c78f337	2007-01-12 03:35:51 +0000	[diff] [blame]	1899	single '<tt>i1</tt>' value and two '<tt>label</tt>' values. The
Reid Spencer	de15194	2007-02-19 23:54:10 +0000	[diff] [blame]	1900	unconditional form of the '<tt>br</tt>' instruction takes a single
				1901	'<tt>label</tt>' value as a target.</p>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1902	<h5>Semantics:</h5>
Reid Spencer	c78f337	2007-01-12 03:35:51 +0000	[diff] [blame]	1903	<p>Upon execution of a conditional '<tt>br</tt>' instruction, the '<tt>i1</tt>'
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1904	argument is evaluated. If the value is <tt>true</tt>, control flows
				1905	to the '<tt>iftrue</tt>' <tt>label</tt> argument. If "cond" is <tt>false</tt>,
				1906	control flows to the '<tt>iffalse</tt>' <tt>label</tt> argument.</p>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1907	<h5>Example:</h5>
Reid Spencer	c78f337	2007-01-12 03:35:51 +0000	[diff] [blame]	1908	<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	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	1909	href="#i_ret">ret</a> i32 1<br>IfUnequal:<br> <a href="#i_ret">ret</a> i32 0<br></pre>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1910	</div>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1911	<!-- _______________________________________________________________________ -->
Chris Lattner	c88c17b	2004-02-24 04:54:45 +0000	[diff] [blame]	1912	<div class="doc_subsubsection">
				1913	<a name="i_switch">'<tt>switch</tt>' Instruction</a>
				1914	</div>
				1915
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1916	<div class="doc_text">
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1917	<h5>Syntax:</h5>
Chris Lattner	c88c17b	2004-02-24 04:54:45 +0000	[diff] [blame]	1918
				1919	<pre>
				1920	switch <intty> <value>, label <defaultdest> [ <intty> <val>, label <dest> ... ]
				1921	</pre>
				1922
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1923	<h5>Overview:</h5>
Chris Lattner	c88c17b	2004-02-24 04:54:45 +0000	[diff] [blame]	1924
				1925	<p>The '<tt>switch</tt>' instruction is used to transfer control flow to one of
				1926	several different places. It is a generalization of the '<tt>br</tt>'
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1927	instruction, allowing a branch to occur to one of many possible
				1928	destinations.</p>
Chris Lattner	c88c17b	2004-02-24 04:54:45 +0000	[diff] [blame]	1929
				1930
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1931	<h5>Arguments:</h5>
Chris Lattner	c88c17b	2004-02-24 04:54:45 +0000	[diff] [blame]	1932
				1933	<p>The '<tt>switch</tt>' instruction uses three parameters: an integer
				1934	comparison value '<tt>value</tt>', a default '<tt>label</tt>' destination, and
				1935	an array of pairs of comparison value constants and '<tt>label</tt>'s. The
				1936	table is not allowed to contain duplicate constant entries.</p>
				1937
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1938	<h5>Semantics:</h5>
Chris Lattner	c88c17b	2004-02-24 04:54:45 +0000	[diff] [blame]	1939
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	1940	<p>The <tt>switch</tt> instruction specifies a table of values and
				1941	destinations. When the '<tt>switch</tt>' instruction is executed, this
John Criswell	8411475	2004-06-25 16:05:06 +0000	[diff] [blame]	1942	table is searched for the given value. If the value is found, control flow is
				1943	transfered to the corresponding destination; otherwise, control flow is
				1944	transfered to the default destination.</p>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1945
Chris Lattner	c88c17b	2004-02-24 04:54:45 +0000	[diff] [blame]	1946	<h5>Implementation:</h5>
				1947
				1948	<p>Depending on properties of the target machine and the particular
				1949	<tt>switch</tt> instruction, this instruction may be code generated in different
John Criswell	8411475	2004-06-25 16:05:06 +0000	[diff] [blame]	1950	ways. For example, it could be generated as a series of chained conditional
				1951	branches or with a lookup table.</p>
Chris Lattner	c88c17b	2004-02-24 04:54:45 +0000	[diff] [blame]	1952
				1953	<h5>Example:</h5>
				1954
				1955	<pre>
				1956	<i>; Emulate a conditional br instruction</i>
Reid Spencer	c78f337	2007-01-12 03:35:51 +0000	[diff] [blame]	1957	%Val = <a href="#i_zext">zext</a> i1 %value to i32
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	1958	switch i32 %Val, label %truedest [i32 0, label %falsedest ]
Chris Lattner	c88c17b	2004-02-24 04:54:45 +0000	[diff] [blame]	1959
				1960	<i>; Emulate an unconditional br instruction</i>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	1961	switch i32 0, label %dest [ ]
Chris Lattner	c88c17b	2004-02-24 04:54:45 +0000	[diff] [blame]	1962
				1963	<i>; Implement a jump table:</i>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	1964	switch i32 %val, label %otherwise [ i32 0, label %onzero
				1965	i32 1, label %onone
				1966	i32 2, label %ontwo ]
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1967	</pre>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1968	</div>
Chris Lattner	bad10ee	2005-05-06 22:57:40 +0000	[diff] [blame]	1969
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1970	<!-- _______________________________________________________________________ -->
Chris Lattner	bad10ee	2005-05-06 22:57:40 +0000	[diff] [blame]	1971	<div class="doc_subsubsection">
				1972	<a name="i_invoke">'<tt>invoke</tt>' Instruction</a>
				1973	</div>
				1974
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1975	<div class="doc_text">
Chris Lattner	bad10ee	2005-05-06 22:57:40 +0000	[diff] [blame]	1976
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1977	<h5>Syntax:</h5>
Chris Lattner	bad10ee	2005-05-06 22:57:40 +0000	[diff] [blame]	1978
				1979	<pre>
Nick Lewycky	d703f65	2008-03-16 07:18:12 +0000	[diff] [blame]	1980	<result> = invoke [<a href="#callingconv">cconv</a>] <ptr to function ty> <function ptr val>(<function args>)
Chris Lattner	76b8a33	2006-05-14 18:23:06 +0000	[diff] [blame]	1981	to label <normal label> unwind label <exception label>
Chris Lattner	bad10ee	2005-05-06 22:57:40 +0000	[diff] [blame]	1982	</pre>
				1983
Chris Lattner	6536cfe	2002-05-06 22:08:29 +0000	[diff] [blame]	1984	<h5>Overview:</h5>
Chris Lattner	bad10ee	2005-05-06 22:57:40 +0000	[diff] [blame]	1985
				1986	<p>The '<tt>invoke</tt>' instruction causes control to transfer to a specified
				1987	function, with the possibility of control flow transfer to either the
John Criswell	e4c57cc	2005-05-12 16:52:32 +0000	[diff] [blame]	1988	'<tt>normal</tt>' label or the
				1989	'<tt>exception</tt>' label. If the callee function returns with the
Chris Lattner	bad10ee	2005-05-06 22:57:40 +0000	[diff] [blame]	1990	"<tt><a href="#i_ret">ret</a></tt>" instruction, control flow will return to the
				1991	"normal" label. If the callee (or any indirect callees) returns with the "<a
John Criswell	e4c57cc	2005-05-12 16:52:32 +0000	[diff] [blame]	1992	href="#i_unwind"><tt>unwind</tt></a>" instruction, control is interrupted and
Devang Patel	c3fc6df	2008-03-10 20:49:15 +0000	[diff] [blame]	1993	continued at the dynamically nearest "exception" label. If the callee function
Devang Patel	0dbb4a1	2008-03-11 05:51:59 +0000	[diff] [blame]	1994	returns multiple values then individual return values are only accessible through
				1995	a '<tt><a href="#i_getresult">getresult</a></tt>' instruction.</p>
Chris Lattner	bad10ee	2005-05-06 22:57:40 +0000	[diff] [blame]	1996
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	1997	<h5>Arguments:</h5>
Chris Lattner	bad10ee	2005-05-06 22:57:40 +0000	[diff] [blame]	1998
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	1999	<p>This instruction requires several arguments:</p>
Chris Lattner	bad10ee	2005-05-06 22:57:40 +0000	[diff] [blame]	2000
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2001	<ol>
Chris Lattner	bad10ee	2005-05-06 22:57:40 +0000	[diff] [blame]	2002	<li>
Duncan Sands	8036ca4	2007-03-30 12:22:09 +0000	[diff] [blame]	2003	The optional "cconv" marker indicates which <a href="#callingconv">calling
Chris Lattner	bad10ee	2005-05-06 22:57:40 +0000	[diff] [blame]	2004	convention</a> the call should use. If none is specified, the call defaults
				2005	to using C calling conventions.
				2006	</li>
				2007	<li>'<tt>ptr to function ty</tt>': shall be the signature of the pointer to
				2008	function value being invoked. In most cases, this is a direct function
				2009	invocation, but indirect <tt>invoke</tt>s are just as possible, branching off
				2010	an arbitrary pointer to function value.
				2011	</li>
				2012
				2013	<li>'<tt>function ptr val</tt>': An LLVM value containing a pointer to a
				2014	function to be invoked. </li>
				2015
				2016	<li>'<tt>function args</tt>': argument list whose types match the function
				2017	signature argument types. If the function signature indicates the function
				2018	accepts a variable number of arguments, the extra arguments can be
				2019	specified. </li>
				2020
				2021	<li>'<tt>normal label</tt>': the label reached when the called function
				2022	executes a '<tt><a href="#i_ret">ret</a></tt>' instruction. </li>
				2023
				2024	<li>'<tt>exception label</tt>': the label reached when a callee returns with
				2025	the <a href="#i_unwind"><tt>unwind</tt></a> instruction. </li>
				2026
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2027	</ol>
Chris Lattner	bad10ee	2005-05-06 22:57:40 +0000	[diff] [blame]	2028
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2029	<h5>Semantics:</h5>
Chris Lattner	bad10ee	2005-05-06 22:57:40 +0000	[diff] [blame]	2030
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2031	<p>This instruction is designed to operate as a standard '<tt><a
Chris Lattner	bad10ee	2005-05-06 22:57:40 +0000	[diff] [blame]	2032	href="#i_call">call</a></tt>' instruction in most regards. The primary
				2033	difference is that it establishes an association with a label, which is used by
				2034	the runtime library to unwind the stack.</p>
				2035
				2036	<p>This instruction is used in languages with destructors to ensure that proper
				2037	cleanup is performed in the case of either a <tt>longjmp</tt> or a thrown
				2038	exception. Additionally, this is important for implementation of
				2039	'<tt>catch</tt>' clauses in high-level languages that support them.</p>
				2040
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2041	<h5>Example:</h5>
Chris Lattner	bad10ee	2005-05-06 22:57:40 +0000	[diff] [blame]	2042	<pre>
Nick Lewycky	d703f65	2008-03-16 07:18:12 +0000	[diff] [blame]	2043	%retval = invoke i32 @Test(i32 15) to label %Continue
Jeff Cohen	6f1cc77	2007-04-22 01:17:39 +0000	[diff] [blame]	2044	unwind label %TestCleanup <i>; {i32}:retval set</i>
Nick Lewycky	d703f65	2008-03-16 07:18:12 +0000	[diff] [blame]	2045	%retval = invoke <a href="#callingconv">coldcc</a> i32 %Testfnptr(i32 15) to label %Continue
Jeff Cohen	6f1cc77	2007-04-22 01:17:39 +0000	[diff] [blame]	2046	unwind label %TestCleanup <i>; {i32}:retval set</i>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2047	</pre>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2048	</div>
Chris Lattner	35eca58	2004-10-16 18:04:13 +0000	[diff] [blame]	2049
				2050
Chris Lattner	27f71f2	2003-09-03 00:41:47 +0000	[diff] [blame]	2051	<!-- _______________________________________________________________________ -->
Chris Lattner	35eca58	2004-10-16 18:04:13 +0000	[diff] [blame]	2052
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2053	<div class="doc_subsubsection"> <a name="i_unwind">'<tt>unwind</tt>'
				2054	Instruction</a> </div>
Chris Lattner	35eca58	2004-10-16 18:04:13 +0000	[diff] [blame]	2055
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2056	<div class="doc_text">
Chris Lattner	35eca58	2004-10-16 18:04:13 +0000	[diff] [blame]	2057
Chris Lattner	27f71f2	2003-09-03 00:41:47 +0000	[diff] [blame]	2058	<h5>Syntax:</h5>
Chris Lattner	35eca58	2004-10-16 18:04:13 +0000	[diff] [blame]	2059	<pre>
				2060	unwind
				2061	</pre>
				2062
Chris Lattner	27f71f2	2003-09-03 00:41:47 +0000	[diff] [blame]	2063	<h5>Overview:</h5>
Chris Lattner	35eca58	2004-10-16 18:04:13 +0000	[diff] [blame]	2064
				2065	<p>The '<tt>unwind</tt>' instruction unwinds the stack, continuing control flow
				2066	at the first callee in the dynamic call stack which used an <a
				2067	href="#i_invoke"><tt>invoke</tt></a> instruction to perform the call. This is
				2068	primarily used to implement exception handling.</p>
				2069
Chris Lattner	27f71f2	2003-09-03 00:41:47 +0000	[diff] [blame]	2070	<h5>Semantics:</h5>
Chris Lattner	35eca58	2004-10-16 18:04:13 +0000	[diff] [blame]	2071
Chris Lattner	72ed200	2008-04-19 21:01:16 +0000	[diff] [blame]	2072	<p>The '<tt>unwind</tt>' instruction causes execution of the current function to
Chris Lattner	35eca58	2004-10-16 18:04:13 +0000	[diff] [blame]	2073	immediately halt. The dynamic call stack is then searched for the first <a
				2074	href="#i_invoke"><tt>invoke</tt></a> instruction on the call stack. Once found,
				2075	execution continues at the "exceptional" destination block specified by the
				2076	<tt>invoke</tt> instruction. If there is no <tt>invoke</tt> instruction in the
				2077	dynamic call chain, undefined behavior results.</p>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2078	</div>
Chris Lattner	35eca58	2004-10-16 18:04:13 +0000	[diff] [blame]	2079
				2080	<!-- _______________________________________________________________________ -->
				2081
				2082	<div class="doc_subsubsection"> <a name="i_unreachable">'<tt>unreachable</tt>'
				2083	Instruction</a> </div>
				2084
				2085	<div class="doc_text">
				2086
				2087	<h5>Syntax:</h5>
				2088	<pre>
				2089	unreachable
				2090	</pre>
				2091
				2092	<h5>Overview:</h5>
				2093
				2094	<p>The '<tt>unreachable</tt>' instruction has no defined semantics. This
				2095	instruction is used to inform the optimizer that a particular portion of the
				2096	code is not reachable. This can be used to indicate that the code after a
				2097	no-return function cannot be reached, and other facts.</p>
				2098
				2099	<h5>Semantics:</h5>
				2100
				2101	<p>The '<tt>unreachable</tt>' instruction has no defined semantics.</p>
				2102	</div>
				2103
				2104
				2105
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2106	<!-- ======================================================================= -->
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2107	<div class="doc_subsection"> <a name="binaryops">Binary Operations</a> </div>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2108	<div class="doc_text">
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2109	<p>Binary operators are used to do most of the computation in a
Chris Lattner	5a15814	2008-04-01 18:47:32 +0000	[diff] [blame]	2110	program. They require two operands of the same type, execute an operation on them, and
John Criswell	9e2485c	2004-12-10 15:51:16 +0000	[diff] [blame]	2111	produce a single value. The operands might represent
Reid Spencer	485bad1	2007-02-15 03:07:05 +0000	[diff] [blame]	2112	multiple data, as is the case with the <a href="#t_vector">vector</a> data type.
Chris Lattner	5a15814	2008-04-01 18:47:32 +0000	[diff] [blame]	2113	The result value has the same type as its operands.</p>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2114	<p>There are several different binary operators:</p>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2115	</div>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2116	<!-- _______________________________________________________________________ -->
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2117	<div class="doc_subsubsection">
				2118	<a name="i_add">'<tt>add</tt>' Instruction</a>
				2119	</div>
				2120
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2121	<div class="doc_text">
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2122
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2123	<h5>Syntax:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2124
				2125	<pre>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2126	<result> = add <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2127	</pre>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2128
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2129	<h5>Overview:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2130
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2131	<p>The '<tt>add</tt>' instruction returns the sum of its two operands.</p>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2132
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2133	<h5>Arguments:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2134
				2135	<p>The two arguments to the '<tt>add</tt>' instruction must be <a
				2136	href="#t_integer">integer</a>, <a href="#t_floating">floating point</a>, or
				2137	<a href="#t_vector">vector</a> values. Both arguments must have identical
				2138	types.</p>
				2139
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2140	<h5>Semantics:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2141
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2142	<p>The value produced is the integer or floating point sum of the two
				2143	operands.</p>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2144
Chris Lattner	5ec8983	2008-01-28 00:36:27 +0000	[diff] [blame]	2145	<p>If an integer sum has unsigned overflow, the result returned is the
				2146	mathematical result modulo 2<sup>n</sup>, where n is the bit width of
				2147	the result.</p>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2148
Chris Lattner	5ec8983	2008-01-28 00:36:27 +0000	[diff] [blame]	2149	<p>Because LLVM integers use a two's complement representation, this
				2150	instruction is appropriate for both signed and unsigned integers.</p>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2151
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2152	<h5>Example:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2153
				2154	<pre>
				2155	<result> = add i32 4, %var <i>; yields {i32}:result = 4 + %var</i>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2156	</pre>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2157	</div>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2158	<!-- _______________________________________________________________________ -->
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2159	<div class="doc_subsubsection">
				2160	<a name="i_sub">'<tt>sub</tt>' Instruction</a>
				2161	</div>
				2162
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2163	<div class="doc_text">
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2164
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2165	<h5>Syntax:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2166
				2167	<pre>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2168	<result> = sub <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2169	</pre>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2170
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2171	<h5>Overview:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2172
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2173	<p>The '<tt>sub</tt>' instruction returns the difference of its two
				2174	operands.</p>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2175
				2176	<p>Note that the '<tt>sub</tt>' instruction is used to represent the
				2177	'<tt>neg</tt>' instruction present in most other intermediate
				2178	representations.</p>
				2179
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2180	<h5>Arguments:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2181
				2182	<p>The two arguments to the '<tt>sub</tt>' instruction must be <a
				2183	href="#t_integer">integer</a>, <a href="#t_floating">floating point</a>,
				2184	or <a href="#t_vector">vector</a> values. Both arguments must have identical
				2185	types.</p>
				2186
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2187	<h5>Semantics:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2188
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2189	<p>The value produced is the integer or floating point difference of
				2190	the two operands.</p>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2191
Chris Lattner	5ec8983	2008-01-28 00:36:27 +0000	[diff] [blame]	2192	<p>If an integer difference has unsigned overflow, the result returned is the
				2193	mathematical result modulo 2<sup>n</sup>, where n is the bit width of
				2194	the result.</p>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2195
Chris Lattner	5ec8983	2008-01-28 00:36:27 +0000	[diff] [blame]	2196	<p>Because LLVM integers use a two's complement representation, this
				2197	instruction is appropriate for both signed and unsigned integers.</p>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2198
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2199	<h5>Example:</h5>
Bill Wendling	aac388b	2007-05-29 09:42:13 +0000	[diff] [blame]	2200	<pre>
				2201	<result> = sub i32 4, %var <i>; yields {i32}:result = 4 - %var</i>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	2202	<result> = sub i32 0, %val <i>; yields {i32}:result = -%var</i>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2203	</pre>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2204	</div>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2205
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2206	<!-- _______________________________________________________________________ -->
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2207	<div class="doc_subsubsection">
				2208	<a name="i_mul">'<tt>mul</tt>' Instruction</a>
				2209	</div>
				2210
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2211	<div class="doc_text">
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2212
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2213	<h5>Syntax:</h5>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2214	<pre> <result> = mul <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2215	</pre>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2216	<h5>Overview:</h5>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2217	<p>The '<tt>mul</tt>' instruction returns the product of its two
				2218	operands.</p>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2219
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2220	<h5>Arguments:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2221
				2222	<p>The two arguments to the '<tt>mul</tt>' instruction must be <a
				2223	href="#t_integer">integer</a>, <a href="#t_floating">floating point</a>,
				2224	or <a href="#t_vector">vector</a> values. Both arguments must have identical
				2225	types.</p>
				2226
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2227	<h5>Semantics:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2228
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2229	<p>The value produced is the integer or floating point product of the
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2230	two operands.</p>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2231
Chris Lattner	5ec8983	2008-01-28 00:36:27 +0000	[diff] [blame]	2232	<p>If the result of an integer multiplication has unsigned overflow,
				2233	the result returned is the mathematical result modulo
				2234	2<sup>n</sup>, where n is the bit width of the result.</p>
				2235	<p>Because LLVM integers use a two's complement representation, and the
				2236	result is the same width as the operands, this instruction returns the
				2237	correct result for both signed and unsigned integers. If a full product
				2238	(e.g. <tt>i32</tt>x<tt>i32</tt>-><tt>i64</tt>) is needed, the operands
				2239	should be sign-extended or zero-extended as appropriate to the
				2240	width of the full product.</p>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2241	<h5>Example:</h5>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	2242	<pre> <result> = mul i32 4, %var <i>; yields {i32}:result = 4 * %var</i>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2243	</pre>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2244	</div>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2245
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2246	<!-- _______________________________________________________________________ -->
Reid Spencer	1628cec	2006-10-26 06:15:43 +0000	[diff] [blame]	2247	<div class="doc_subsubsection"> <a name="i_udiv">'<tt>udiv</tt>' Instruction
				2248	</a></div>
				2249	<div class="doc_text">
				2250	<h5>Syntax:</h5>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2251	<pre> <result> = udiv <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Reid Spencer	1628cec	2006-10-26 06:15:43 +0000	[diff] [blame]	2252	</pre>
				2253	<h5>Overview:</h5>
				2254	<p>The '<tt>udiv</tt>' instruction returns the quotient of its two
				2255	operands.</p>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2256
Reid Spencer	1628cec	2006-10-26 06:15:43 +0000	[diff] [blame]	2257	<h5>Arguments:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2258
Reid Spencer	1628cec	2006-10-26 06:15:43 +0000	[diff] [blame]	2259	<p>The two arguments to the '<tt>udiv</tt>' instruction must be
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2260	<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
				2261	values. Both arguments must have identical types.</p>
				2262
Reid Spencer	1628cec	2006-10-26 06:15:43 +0000	[diff] [blame]	2263	<h5>Semantics:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2264
Chris Lattner	5ec8983	2008-01-28 00:36:27 +0000	[diff] [blame]	2265	<p>The value produced is the unsigned integer quotient of the two operands.</p>
				2266	<p>Note that unsigned integer division and signed integer division are distinct
				2267	operations; for signed integer division, use '<tt>sdiv</tt>'.</p>
				2268	<p>Division by zero leads to undefined behavior.</p>
Reid Spencer	1628cec	2006-10-26 06:15:43 +0000	[diff] [blame]	2269	<h5>Example:</h5>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	2270	<pre> <result> = udiv i32 4, %var <i>; yields {i32}:result = 4 / %var</i>
Reid Spencer	1628cec	2006-10-26 06:15:43 +0000	[diff] [blame]	2271	</pre>
				2272	</div>
				2273	<!-- _______________________________________________________________________ -->
				2274	<div class="doc_subsubsection"> <a name="i_sdiv">'<tt>sdiv</tt>' Instruction
				2275	</a> </div>
				2276	<div class="doc_text">
				2277	<h5>Syntax:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2278	<pre>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2279	<result> = sdiv <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Reid Spencer	1628cec	2006-10-26 06:15:43 +0000	[diff] [blame]	2280	</pre>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2281
Reid Spencer	1628cec	2006-10-26 06:15:43 +0000	[diff] [blame]	2282	<h5>Overview:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2283
Reid Spencer	1628cec	2006-10-26 06:15:43 +0000	[diff] [blame]	2284	<p>The '<tt>sdiv</tt>' instruction returns the quotient of its two
				2285	operands.</p>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2286
Reid Spencer	1628cec	2006-10-26 06:15:43 +0000	[diff] [blame]	2287	<h5>Arguments:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2288
				2289	<p>The two arguments to the '<tt>sdiv</tt>' instruction must be
				2290	<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
				2291	values. Both arguments must have identical types.</p>
				2292
Reid Spencer	1628cec	2006-10-26 06:15:43 +0000	[diff] [blame]	2293	<h5>Semantics:</h5>
Chris Lattner	a73afe0	2008-04-01 18:45:27 +0000	[diff] [blame]	2294	<p>The value produced is the signed integer quotient of the two operands rounded towards zero.</p>
Chris Lattner	5ec8983	2008-01-28 00:36:27 +0000	[diff] [blame]	2295	<p>Note that signed integer division and unsigned integer division are distinct
				2296	operations; for unsigned integer division, use '<tt>udiv</tt>'.</p>
				2297	<p>Division by zero leads to undefined behavior. Overflow also leads to
				2298	undefined behavior; this is a rare case, but can occur, for example,
				2299	by doing a 32-bit division of -2147483648 by -1.</p>
Reid Spencer	1628cec	2006-10-26 06:15:43 +0000	[diff] [blame]	2300	<h5>Example:</h5>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	2301	<pre> <result> = sdiv i32 4, %var <i>; yields {i32}:result = 4 / %var</i>
Reid Spencer	1628cec	2006-10-26 06:15:43 +0000	[diff] [blame]	2302	</pre>
				2303	</div>
				2304	<!-- _______________________________________________________________________ -->
				2305	<div class="doc_subsubsection"> <a name="i_fdiv">'<tt>fdiv</tt>'
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2306	Instruction</a> </div>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2307	<div class="doc_text">
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2308	<h5>Syntax:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2309	<pre>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2310	<result> = fdiv <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2311	</pre>
				2312	<h5>Overview:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2313
Reid Spencer	1628cec	2006-10-26 06:15:43 +0000	[diff] [blame]	2314	<p>The '<tt>fdiv</tt>' instruction returns the quotient of its two
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2315	operands.</p>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2316
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2317	<h5>Arguments:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2318
Jeff Cohen	6f1cc77	2007-04-22 01:17:39 +0000	[diff] [blame]	2319	<p>The two arguments to the '<tt>fdiv</tt>' instruction must be
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2320	<a href="#t_floating">floating point</a> or <a href="#t_vector">vector</a>
				2321	of floating point values. Both arguments must have identical types.</p>
				2322
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2323	<h5>Semantics:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2324
Reid Spencer	1628cec	2006-10-26 06:15:43 +0000	[diff] [blame]	2325	<p>The value produced is the floating point quotient of the two operands.</p>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2326
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2327	<h5>Example:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2328
				2329	<pre>
				2330	<result> = fdiv float 4.0, %var <i>; yields {float}:result = 4.0 / %var</i>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2331	</pre>
				2332	</div>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2333
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2334	<!-- _______________________________________________________________________ -->
Reid Spencer	0a783f7	2006-11-02 01:53:59 +0000	[diff] [blame]	2335	<div class="doc_subsubsection"> <a name="i_urem">'<tt>urem</tt>' Instruction</a>
				2336	</div>
				2337	<div class="doc_text">
				2338	<h5>Syntax:</h5>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2339	<pre> <result> = urem <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Reid Spencer	0a783f7	2006-11-02 01:53:59 +0000	[diff] [blame]	2340	</pre>
				2341	<h5>Overview:</h5>
				2342	<p>The '<tt>urem</tt>' instruction returns the remainder from the
				2343	unsigned division of its two arguments.</p>
				2344	<h5>Arguments:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2345	<p>The two arguments to the '<tt>urem</tt>' instruction must be
				2346	<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
				2347	values. Both arguments must have identical types.</p>
Reid Spencer	0a783f7	2006-11-02 01:53:59 +0000	[diff] [blame]	2348	<h5>Semantics:</h5>
				2349	<p>This instruction returns the unsigned integer <i>remainder</i> of a division.
Chris Lattner	a73afe0	2008-04-01 18:45:27 +0000	[diff] [blame]	2350	This instruction always performs an unsigned division to get the remainder.</p>
Chris Lattner	5ec8983	2008-01-28 00:36:27 +0000	[diff] [blame]	2351	<p>Note that unsigned integer remainder and signed integer remainder are
				2352	distinct operations; for signed integer remainder, use '<tt>srem</tt>'.</p>
				2353	<p>Taking the remainder of a division by zero leads to undefined behavior.</p>
Reid Spencer	0a783f7	2006-11-02 01:53:59 +0000	[diff] [blame]	2354	<h5>Example:</h5>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	2355	<pre> <result> = urem i32 4, %var <i>; yields {i32}:result = 4 % %var</i>
Reid Spencer	0a783f7	2006-11-02 01:53:59 +0000	[diff] [blame]	2356	</pre>
				2357
				2358	</div>
				2359	<!-- _______________________________________________________________________ -->
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2360	<div class="doc_subsubsection">
				2361	<a name="i_srem">'<tt>srem</tt>' Instruction</a>
				2362	</div>
				2363
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2364	<div class="doc_text">
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2365
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2366	<h5>Syntax:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2367
				2368	<pre>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2369	<result> = srem <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2370	</pre>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2371
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2372	<h5>Overview:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2373
Reid Spencer	0a783f7	2006-11-02 01:53:59 +0000	[diff] [blame]	2374	<p>The '<tt>srem</tt>' instruction returns the remainder from the
Dan Gohman	8017631	2007-11-05 23:35:22 +0000	[diff] [blame]	2375	signed division of its two operands. This instruction can also take
				2376	<a href="#t_vector">vector</a> versions of the values in which case
				2377	the elements must be integers.</p>
Chris Lattner	c7d3ab3	2008-01-04 04:33:49 +0000	[diff] [blame]	2378
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2379	<h5>Arguments:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2380
Reid Spencer	0a783f7	2006-11-02 01:53:59 +0000	[diff] [blame]	2381	<p>The two arguments to the '<tt>srem</tt>' instruction must be
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2382	<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
				2383	values. Both arguments must have identical types.</p>
				2384
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2385	<h5>Semantics:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2386
Reid Spencer	0a783f7	2006-11-02 01:53:59 +0000	[diff] [blame]	2387	<p>This instruction returns the <i>remainder</i> of a division (where the result
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2388	has the same sign as the dividend, <tt>op1</tt>), not the <i>modulo</i>
				2389	operator (where the result has the same sign as the divisor, <tt>op2</tt>) of
Reid Spencer	c9fdfc8	2007-03-24 22:23:39 +0000	[diff] [blame]	2390	a value. For more information about the difference, see <a
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2391	href="http://mathforum.org/dr.math/problems/anne.4.28.99.html">The
Reid Spencer	c9fdfc8	2007-03-24 22:23:39 +0000	[diff] [blame]	2392	Math Forum</a>. For a table of how this is implemented in various languages,
Reid Spencer	64f5c6c	2007-03-24 22:40:44 +0000	[diff] [blame]	2393	please see <a href="http://en.wikipedia.org/wiki/Modulo_operation">
Reid Spencer	c9fdfc8	2007-03-24 22:23:39 +0000	[diff] [blame]	2394	Wikipedia: modulo operation</a>.</p>
Chris Lattner	5ec8983	2008-01-28 00:36:27 +0000	[diff] [blame]	2395	<p>Note that signed integer remainder and unsigned integer remainder are
				2396	distinct operations; for unsigned integer remainder, use '<tt>urem</tt>'.</p>
				2397	<p>Taking the remainder of a division by zero leads to undefined behavior.
				2398	Overflow also leads to undefined behavior; this is a rare case, but can occur,
				2399	for example, by taking the remainder of a 32-bit division of -2147483648 by -1.
				2400	(The remainder doesn't actually overflow, but this rule lets srem be
				2401	implemented using instructions that return both the result of the division
				2402	and the remainder.)</p>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2403	<h5>Example:</h5>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	2404	<pre> <result> = srem i32 4, %var <i>; yields {i32}:result = 4 % %var</i>
Reid Spencer	0a783f7	2006-11-02 01:53:59 +0000	[diff] [blame]	2405	</pre>
				2406
				2407	</div>
				2408	<!-- _______________________________________________________________________ -->
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2409	<div class="doc_subsubsection">
				2410	<a name="i_frem">'<tt>frem</tt>' Instruction</a> </div>
				2411
Reid Spencer	0a783f7	2006-11-02 01:53:59 +0000	[diff] [blame]	2412	<div class="doc_text">
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2413
Reid Spencer	0a783f7	2006-11-02 01:53:59 +0000	[diff] [blame]	2414	<h5>Syntax:</h5>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2415	<pre> <result> = frem <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Reid Spencer	0a783f7	2006-11-02 01:53:59 +0000	[diff] [blame]	2416	</pre>
				2417	<h5>Overview:</h5>
				2418	<p>The '<tt>frem</tt>' instruction returns the remainder from the
				2419	division of its two operands.</p>
				2420	<h5>Arguments:</h5>
				2421	<p>The two arguments to the '<tt>frem</tt>' instruction must be
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2422	<a href="#t_floating">floating point</a> or <a href="#t_vector">vector</a>
				2423	of floating point values. Both arguments must have identical types.</p>
				2424
Reid Spencer	0a783f7	2006-11-02 01:53:59 +0000	[diff] [blame]	2425	<h5>Semantics:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2426
Chris Lattner	a73afe0	2008-04-01 18:45:27 +0000	[diff] [blame]	2427	<p>This instruction returns the <i>remainder</i> of a division.
				2428	The remainder has the same sign as the dividend.</p>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2429
Reid Spencer	0a783f7	2006-11-02 01:53:59 +0000	[diff] [blame]	2430	<h5>Example:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2431
				2432	<pre>
				2433	<result> = frem float 4.0, %var <i>; yields {float}:result = 4.0 % %var</i>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2434	</pre>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2435	</div>
Robert Bocchino	7b81c75	2006-02-17 21:18:08 +0000	[diff] [blame]	2436
Reid Spencer	8e11bf8	2007-02-02 13:57:07 +0000	[diff] [blame]	2437	<!-- ======================================================================= -->
				2438	<div class="doc_subsection"> <a name="bitwiseops">Bitwise Binary
				2439	Operations</a> </div>
				2440	<div class="doc_text">
				2441	<p>Bitwise binary operators are used to do various forms of
				2442	bit-twiddling in a program. They are generally very efficient
				2443	instructions and can commonly be strength reduced from other
Chris Lattner	a73afe0	2008-04-01 18:45:27 +0000	[diff] [blame]	2444	instructions. They require two operands of the same type, execute an operation on them,
				2445	and produce a single value. The resulting value is the same type as its operands.</p>
Reid Spencer	8e11bf8	2007-02-02 13:57:07 +0000	[diff] [blame]	2446	</div>
				2447
Reid Spencer	569f2fa	2007-01-31 21:39:12 +0000	[diff] [blame]	2448	<!-- _______________________________________________________________________ -->
				2449	<div class="doc_subsubsection"> <a name="i_shl">'<tt>shl</tt>'
				2450	Instruction</a> </div>
				2451	<div class="doc_text">
				2452	<h5>Syntax:</h5>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2453	<pre> <result> = shl <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Reid Spencer	569f2fa	2007-01-31 21:39:12 +0000	[diff] [blame]	2454	</pre>
Chris Lattner	6ccc2d5	2007-10-03 21:01:14 +0000	[diff] [blame]	2455
Reid Spencer	569f2fa	2007-01-31 21:39:12 +0000	[diff] [blame]	2456	<h5>Overview:</h5>
Chris Lattner	6ccc2d5	2007-10-03 21:01:14 +0000	[diff] [blame]	2457
Reid Spencer	569f2fa	2007-01-31 21:39:12 +0000	[diff] [blame]	2458	<p>The '<tt>shl</tt>' instruction returns the first operand shifted to
				2459	the left a specified number of bits.</p>
Chris Lattner	6ccc2d5	2007-10-03 21:01:14 +0000	[diff] [blame]	2460
Reid Spencer	569f2fa	2007-01-31 21:39:12 +0000	[diff] [blame]	2461	<h5>Arguments:</h5>
Chris Lattner	6ccc2d5	2007-10-03 21:01:14 +0000	[diff] [blame]	2462
Reid Spencer	569f2fa	2007-01-31 21:39:12 +0000	[diff] [blame]	2463	<p>Both arguments to the '<tt>shl</tt>' instruction must be the same <a
Nate Begeman	5bc1ea0	2008-07-29 15:49:41 +0000	[diff] [blame]	2464	href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2465	type. '<tt>op2</tt>' is treated as an unsigned value.</p>
Chris Lattner	6ccc2d5	2007-10-03 21:01:14 +0000	[diff] [blame]	2466
Reid Spencer	569f2fa	2007-01-31 21:39:12 +0000	[diff] [blame]	2467	<h5>Semantics:</h5>
Chris Lattner	6ccc2d5	2007-10-03 21:01:14 +0000	[diff] [blame]	2468
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2469	<p>The value produced is <tt>op1</tt> * 2<sup><tt>op2</tt></sup> mod 2<sup>n</sup>,
				2470	where n is the width of the result. If <tt>op2</tt> is (statically or dynamically) negative or
				2471	equal to or larger than the number of bits in <tt>op1</tt>, the result is undefined.</p>
Chris Lattner	6ccc2d5	2007-10-03 21:01:14 +0000	[diff] [blame]	2472
Reid Spencer	569f2fa	2007-01-31 21:39:12 +0000	[diff] [blame]	2473	<h5>Example:</h5><pre>
				2474	<result> = shl i32 4, %var <i>; yields {i32}: 4 << %var</i>
				2475	<result> = shl i32 4, 2 <i>; yields {i32}: 16</i>
				2476	<result> = shl i32 1, 10 <i>; yields {i32}: 1024</i>
Chris Lattner	6ccc2d5	2007-10-03 21:01:14 +0000	[diff] [blame]	2477	<result> = shl i32 1, 32 <i>; undefined</i>
Reid Spencer	569f2fa	2007-01-31 21:39:12 +0000	[diff] [blame]	2478	</pre>
				2479	</div>
				2480	<!-- _______________________________________________________________________ -->
				2481	<div class="doc_subsubsection"> <a name="i_lshr">'<tt>lshr</tt>'
				2482	Instruction</a> </div>
				2483	<div class="doc_text">
				2484	<h5>Syntax:</h5>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2485	<pre> <result> = lshr <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Reid Spencer	569f2fa	2007-01-31 21:39:12 +0000	[diff] [blame]	2486	</pre>
				2487
				2488	<h5>Overview:</h5>
				2489	<p>The '<tt>lshr</tt>' instruction (logical shift right) returns the first
Jeff Cohen	6f1cc77	2007-04-22 01:17:39 +0000	[diff] [blame]	2490	operand shifted to the right a specified number of bits with zero fill.</p>
Reid Spencer	569f2fa	2007-01-31 21:39:12 +0000	[diff] [blame]	2491
				2492	<h5>Arguments:</h5>
				2493	<p>Both arguments to the '<tt>lshr</tt>' instruction must be the same
Nate Begeman	5bc1ea0	2008-07-29 15:49:41 +0000	[diff] [blame]	2494	<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2495	type. '<tt>op2</tt>' is treated as an unsigned value.</p>
Reid Spencer	569f2fa	2007-01-31 21:39:12 +0000	[diff] [blame]	2496
				2497	<h5>Semantics:</h5>
Chris Lattner	6ccc2d5	2007-10-03 21:01:14 +0000	[diff] [blame]	2498
Reid Spencer	569f2fa	2007-01-31 21:39:12 +0000	[diff] [blame]	2499	<p>This instruction always performs a logical shift right operation. The most
				2500	significant bits of the result will be filled with zero bits after the
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2501	shift. If <tt>op2</tt> is (statically or dynamically) equal to or larger than
				2502	the number of bits in <tt>op1</tt>, the result is undefined.</p>
Reid Spencer	569f2fa	2007-01-31 21:39:12 +0000	[diff] [blame]	2503
				2504	<h5>Example:</h5>
				2505	<pre>
				2506	<result> = lshr i32 4, 1 <i>; yields {i32}:result = 2</i>
				2507	<result> = lshr i32 4, 2 <i>; yields {i32}:result = 1</i>
				2508	<result> = lshr i8 4, 3 <i>; yields {i8}:result = 0</i>
				2509	<result> = lshr i8 -2, 1 <i>; yields {i8}:result = 0x7FFFFFFF </i>
Chris Lattner	6ccc2d5	2007-10-03 21:01:14 +0000	[diff] [blame]	2510	<result> = lshr i32 1, 32 <i>; undefined</i>
Reid Spencer	569f2fa	2007-01-31 21:39:12 +0000	[diff] [blame]	2511	</pre>
				2512	</div>
				2513
Reid Spencer	8e11bf8	2007-02-02 13:57:07 +0000	[diff] [blame]	2514	<!-- _______________________________________________________________________ -->
Reid Spencer	569f2fa	2007-01-31 21:39:12 +0000	[diff] [blame]	2515	<div class="doc_subsubsection"> <a name="i_ashr">'<tt>ashr</tt>'
				2516	Instruction</a> </div>
				2517	<div class="doc_text">
				2518
				2519	<h5>Syntax:</h5>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2520	<pre> <result> = ashr <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Reid Spencer	569f2fa	2007-01-31 21:39:12 +0000	[diff] [blame]	2521	</pre>
				2522
				2523	<h5>Overview:</h5>
				2524	<p>The '<tt>ashr</tt>' instruction (arithmetic shift right) returns the first
Jeff Cohen	6f1cc77	2007-04-22 01:17:39 +0000	[diff] [blame]	2525	operand shifted to the right a specified number of bits with sign extension.</p>
Reid Spencer	569f2fa	2007-01-31 21:39:12 +0000	[diff] [blame]	2526
				2527	<h5>Arguments:</h5>
				2528	<p>Both arguments to the '<tt>ashr</tt>' instruction must be the same
Nate Begeman	5bc1ea0	2008-07-29 15:49:41 +0000	[diff] [blame]	2529	<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2530	type. '<tt>op2</tt>' is treated as an unsigned value.</p>
Reid Spencer	569f2fa	2007-01-31 21:39:12 +0000	[diff] [blame]	2531
				2532	<h5>Semantics:</h5>
				2533	<p>This instruction always performs an arithmetic shift right operation,
				2534	The most significant bits of the result will be filled with the sign bit
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2535	of <tt>op1</tt>. If <tt>op2</tt> is (statically or dynamically) equal to or
				2536	larger than the number of bits in <tt>op1</tt>, the result is undefined.
Chris Lattner	6ccc2d5	2007-10-03 21:01:14 +0000	[diff] [blame]	2537	</p>
Reid Spencer	569f2fa	2007-01-31 21:39:12 +0000	[diff] [blame]	2538
				2539	<h5>Example:</h5>
				2540	<pre>
				2541	<result> = ashr i32 4, 1 <i>; yields {i32}:result = 2</i>
				2542	<result> = ashr i32 4, 2 <i>; yields {i32}:result = 1</i>
				2543	<result> = ashr i8 4, 3 <i>; yields {i8}:result = 0</i>
				2544	<result> = ashr i8 -2, 1 <i>; yields {i8}:result = -1</i>
Chris Lattner	6ccc2d5	2007-10-03 21:01:14 +0000	[diff] [blame]	2545	<result> = ashr i32 1, 32 <i>; undefined</i>
Reid Spencer	569f2fa	2007-01-31 21:39:12 +0000	[diff] [blame]	2546	</pre>
				2547	</div>
				2548
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2549	<!-- _______________________________________________________________________ -->
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2550	<div class="doc_subsubsection"> <a name="i_and">'<tt>and</tt>'
				2551	Instruction</a> </div>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2552
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2553	<div class="doc_text">
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2554
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2555	<h5>Syntax:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2556
				2557	<pre>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2558	<result> = and <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2559	</pre>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2560
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2561	<h5>Overview:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2562
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2563	<p>The '<tt>and</tt>' instruction returns the bitwise logical and of
				2564	its two operands.</p>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2565
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2566	<h5>Arguments:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2567
				2568	<p>The two arguments to the '<tt>and</tt>' instruction must be
				2569	<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
				2570	values. Both arguments must have identical types.</p>
				2571
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2572	<h5>Semantics:</h5>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2573	<p>The truth table used for the '<tt>and</tt>' instruction is:</p>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2574	<p> </p>
Misha Brukman	daa4cb0	2004-03-01 17:47:27 +0000	[diff] [blame]	2575	<div style="align: center">
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2576	<table border="1" cellspacing="0" cellpadding="4">
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2577	<tbody>
				2578	<tr>
				2579	<td>In0</td>
				2580	<td>In1</td>
				2581	<td>Out</td>
				2582	</tr>
				2583	<tr>
				2584	<td>0</td>
				2585	<td>0</td>
				2586	<td>0</td>
				2587	</tr>
				2588	<tr>
				2589	<td>0</td>
				2590	<td>1</td>
				2591	<td>0</td>
				2592	</tr>
				2593	<tr>
				2594	<td>1</td>
				2595	<td>0</td>
				2596	<td>0</td>
				2597	</tr>
				2598	<tr>
				2599	<td>1</td>
				2600	<td>1</td>
				2601	<td>1</td>
				2602	</tr>
				2603	</tbody>
				2604	</table>
Misha Brukman	daa4cb0	2004-03-01 17:47:27 +0000	[diff] [blame]	2605	</div>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2606	<h5>Example:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2607	<pre>
				2608	<result> = and i32 4, %var <i>; yields {i32}:result = 4 & %var</i>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	2609	<result> = and i32 15, 40 <i>; yields {i32}:result = 8</i>
				2610	<result> = and i32 4, 8 <i>; yields {i32}:result = 0</i>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2611	</pre>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2612	</div>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2613	<!-- _______________________________________________________________________ -->
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2614	<div class="doc_subsubsection"> <a name="i_or">'<tt>or</tt>' Instruction</a> </div>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2615	<div class="doc_text">
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2616	<h5>Syntax:</h5>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2617	<pre> <result> = or <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2618	</pre>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2619	<h5>Overview:</h5>
				2620	<p>The '<tt>or</tt>' instruction returns the bitwise logical inclusive
				2621	or of its two operands.</p>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2622	<h5>Arguments:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2623
				2624	<p>The two arguments to the '<tt>or</tt>' instruction must be
				2625	<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
				2626	values. Both arguments must have identical types.</p>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2627	<h5>Semantics:</h5>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2628	<p>The truth table used for the '<tt>or</tt>' instruction is:</p>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2629	<p> </p>
Misha Brukman	daa4cb0	2004-03-01 17:47:27 +0000	[diff] [blame]	2630	<div style="align: center">
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2631	<table border="1" cellspacing="0" cellpadding="4">
				2632	<tbody>
				2633	<tr>
				2634	<td>In0</td>
				2635	<td>In1</td>
				2636	<td>Out</td>
				2637	</tr>
				2638	<tr>
				2639	<td>0</td>
				2640	<td>0</td>
				2641	<td>0</td>
				2642	</tr>
				2643	<tr>
				2644	<td>0</td>
				2645	<td>1</td>
				2646	<td>1</td>
				2647	</tr>
				2648	<tr>
				2649	<td>1</td>
				2650	<td>0</td>
				2651	<td>1</td>
				2652	</tr>
				2653	<tr>
				2654	<td>1</td>
				2655	<td>1</td>
				2656	<td>1</td>
				2657	</tr>
				2658	</tbody>
				2659	</table>
Misha Brukman	daa4cb0	2004-03-01 17:47:27 +0000	[diff] [blame]	2660	</div>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2661	<h5>Example:</h5>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	2662	<pre> <result> = or i32 4, %var <i>; yields {i32}:result = 4 \| %var</i>
				2663	<result> = or i32 15, 40 <i>; yields {i32}:result = 47</i>
				2664	<result> = or i32 4, 8 <i>; yields {i32}:result = 12</i>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2665	</pre>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2666	</div>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2667	<!-- _______________________________________________________________________ -->
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2668	<div class="doc_subsubsection"> <a name="i_xor">'<tt>xor</tt>'
				2669	Instruction</a> </div>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2670	<div class="doc_text">
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2671	<h5>Syntax:</h5>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	2672	<pre> <result> = xor <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2673	</pre>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2674	<h5>Overview:</h5>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2675	<p>The '<tt>xor</tt>' instruction returns the bitwise logical exclusive
				2676	or of its two operands. The <tt>xor</tt> is used to implement the
				2677	"one's complement" operation, which is the "~" operator in C.</p>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2678	<h5>Arguments:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2679	<p>The two arguments to the '<tt>xor</tt>' instruction must be
				2680	<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
				2681	values. Both arguments must have identical types.</p>
				2682
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2683	<h5>Semantics:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	2684
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2685	<p>The truth table used for the '<tt>xor</tt>' instruction is:</p>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2686	<p> </p>
Misha Brukman	daa4cb0	2004-03-01 17:47:27 +0000	[diff] [blame]	2687	<div style="align: center">
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2688	<table border="1" cellspacing="0" cellpadding="4">
				2689	<tbody>
				2690	<tr>
				2691	<td>In0</td>
				2692	<td>In1</td>
				2693	<td>Out</td>
				2694	</tr>
				2695	<tr>
				2696	<td>0</td>
				2697	<td>0</td>
				2698	<td>0</td>
				2699	</tr>
				2700	<tr>
				2701	<td>0</td>
				2702	<td>1</td>
				2703	<td>1</td>
				2704	</tr>
				2705	<tr>
				2706	<td>1</td>
				2707	<td>0</td>
				2708	<td>1</td>
				2709	</tr>
				2710	<tr>
				2711	<td>1</td>
				2712	<td>1</td>
				2713	<td>0</td>
				2714	</tr>
				2715	</tbody>
				2716	</table>
Misha Brukman	daa4cb0	2004-03-01 17:47:27 +0000	[diff] [blame]	2717	</div>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	2718	<p> </p>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2719	<h5>Example:</h5>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	2720	<pre> <result> = xor i32 4, %var <i>; yields {i32}:result = 4 ^ %var</i>
				2721	<result> = xor i32 15, 40 <i>; yields {i32}:result = 39</i>
				2722	<result> = xor i32 4, 8 <i>; yields {i32}:result = 12</i>
				2723	<result> = xor i32 %V, -1 <i>; yields {i32}:result = ~%V</i>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2724	</pre>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	2725	</div>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	2726
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	2727	<!-- ======================================================================= -->
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	2728	<div class="doc_subsection">
Chris Lattner	3df241e	2006-04-08 23:07:04 +0000	[diff] [blame]	2729	<a name="vectorops">Vector Operations</a>
				2730	</div>
				2731
				2732	<div class="doc_text">
				2733
				2734	<p>LLVM supports several instructions to represent vector operations in a
Jeff Cohen	6f1cc77	2007-04-22 01:17:39 +0000	[diff] [blame]	2735	target-independent manner. These instructions cover the element-access and
Chris Lattner	3df241e	2006-04-08 23:07:04 +0000	[diff] [blame]	2736	vector-specific operations needed to process vectors effectively. While LLVM
				2737	does directly support these vector operations, many sophisticated algorithms
				2738	will want to use target-specific intrinsics to take full advantage of a specific
				2739	target.</p>
				2740
				2741	</div>
				2742
				2743	<!-- _______________________________________________________________________ -->
				2744	<div class="doc_subsubsection">
				2745	<a name="i_extractelement">'<tt>extractelement</tt>' Instruction</a>
				2746	</div>
				2747
				2748	<div class="doc_text">
				2749
				2750	<h5>Syntax:</h5>
				2751
				2752	<pre>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	2753	<result> = extractelement <n x <ty>> <val>, i32 <idx> <i>; yields <ty></i>
Chris Lattner	3df241e	2006-04-08 23:07:04 +0000	[diff] [blame]	2754	</pre>
				2755
				2756	<h5>Overview:</h5>
				2757
				2758	<p>
				2759	The '<tt>extractelement</tt>' instruction extracts a single scalar
Reid Spencer	485bad1	2007-02-15 03:07:05 +0000	[diff] [blame]	2760	element from a vector at a specified index.
Chris Lattner	3df241e	2006-04-08 23:07:04 +0000	[diff] [blame]	2761	</p>
				2762
				2763
				2764	<h5>Arguments:</h5>
				2765
				2766	<p>
				2767	The first operand of an '<tt>extractelement</tt>' instruction is a
Reid Spencer	485bad1	2007-02-15 03:07:05 +0000	[diff] [blame]	2768	value of <a href="#t_vector">vector</a> type. The second operand is
Chris Lattner	3df241e	2006-04-08 23:07:04 +0000	[diff] [blame]	2769	an index indicating the position from which to extract the element.
				2770	The index may be a variable.</p>
				2771
				2772	<h5>Semantics:</h5>
				2773
				2774	<p>
				2775	The result is a scalar of the same type as the element type of
				2776	<tt>val</tt>. Its value is the value at position <tt>idx</tt> of
				2777	<tt>val</tt>. If <tt>idx</tt> exceeds the length of <tt>val</tt>, the
				2778	results are undefined.
				2779	</p>
				2780
				2781	<h5>Example:</h5>
				2782
				2783	<pre>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	2784	%result = extractelement <4 x i32> %vec, i32 0 <i>; yields i32</i>
Chris Lattner	3df241e	2006-04-08 23:07:04 +0000	[diff] [blame]	2785	</pre>
				2786	</div>
				2787
				2788
				2789	<!-- _______________________________________________________________________ -->
				2790	<div class="doc_subsubsection">
				2791	<a name="i_insertelement">'<tt>insertelement</tt>' Instruction</a>
				2792	</div>
				2793
				2794	<div class="doc_text">
				2795
				2796	<h5>Syntax:</h5>
				2797
				2798	<pre>
Dan Gohman	f3480b9	2008-05-12 23:38:42 +0000	[diff] [blame]	2799	<result> = insertelement <n x <ty>> <val>, <ty> <elt>, i32 <idx> <i>; yields <n x <ty>></i>
Chris Lattner	3df241e	2006-04-08 23:07:04 +0000	[diff] [blame]	2800	</pre>
				2801
				2802	<h5>Overview:</h5>
				2803
				2804	<p>
				2805	The '<tt>insertelement</tt>' instruction inserts a scalar
Reid Spencer	485bad1	2007-02-15 03:07:05 +0000	[diff] [blame]	2806	element into a vector at a specified index.
Chris Lattner	3df241e	2006-04-08 23:07:04 +0000	[diff] [blame]	2807	</p>
				2808
				2809
				2810	<h5>Arguments:</h5>
				2811
				2812	<p>
				2813	The first operand of an '<tt>insertelement</tt>' instruction is a
Reid Spencer	485bad1	2007-02-15 03:07:05 +0000	[diff] [blame]	2814	value of <a href="#t_vector">vector</a> type. The second operand is a
Chris Lattner	3df241e	2006-04-08 23:07:04 +0000	[diff] [blame]	2815	scalar value whose type must equal the element type of the first
				2816	operand. The third operand is an index indicating the position at
				2817	which to insert the value. The index may be a variable.</p>
				2818
				2819	<h5>Semantics:</h5>
				2820
				2821	<p>
Reid Spencer	485bad1	2007-02-15 03:07:05 +0000	[diff] [blame]	2822	The result is a vector of the same type as <tt>val</tt>. Its
Chris Lattner	3df241e	2006-04-08 23:07:04 +0000	[diff] [blame]	2823	element values are those of <tt>val</tt> except at position
				2824	<tt>idx</tt>, where it gets the value <tt>elt</tt>. If <tt>idx</tt>
				2825	exceeds the length of <tt>val</tt>, the results are undefined.
				2826	</p>
				2827
				2828	<h5>Example:</h5>
				2829
				2830	<pre>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	2831	%result = insertelement <4 x i32> %vec, i32 1, i32 0 <i>; yields <4 x i32></i>
Chris Lattner	3df241e	2006-04-08 23:07:04 +0000	[diff] [blame]	2832	</pre>
				2833	</div>
				2834
				2835	<!-- _______________________________________________________________________ -->
				2836	<div class="doc_subsubsection">
				2837	<a name="i_shufflevector">'<tt>shufflevector</tt>' Instruction</a>
				2838	</div>
				2839
				2840	<div class="doc_text">
				2841
				2842	<h5>Syntax:</h5>
				2843
				2844	<pre>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	2845	<result> = shufflevector <n x <ty>> <v1>, <n x <ty>> <v2>, <n x i32> <mask> <i>; yields <n x <ty>></i>
Chris Lattner	3df241e	2006-04-08 23:07:04 +0000	[diff] [blame]	2846	</pre>
				2847
				2848	<h5>Overview:</h5>
				2849
				2850	<p>
				2851	The '<tt>shufflevector</tt>' instruction constructs a permutation of elements
				2852	from two input vectors, returning a vector of the same type.
				2853	</p>
				2854
				2855	<h5>Arguments:</h5>
				2856
				2857	<p>
				2858	The first two operands of a '<tt>shufflevector</tt>' instruction are vectors
				2859	with types that match each other and types that match the result of the
				2860	instruction. The third argument is a shuffle mask, which has the same number
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	2861	of elements as the other vector type, but whose element type is always 'i32'.
Chris Lattner	3df241e	2006-04-08 23:07:04 +0000	[diff] [blame]	2862	</p>
				2863
				2864	<p>
				2865	The shuffle mask operand is required to be a constant vector with either
				2866	constant integer or undef values.
				2867	</p>
				2868
				2869	<h5>Semantics:</h5>
				2870
				2871	<p>
				2872	The elements of the two input vectors are numbered from left to right across
				2873	both of the vectors. The shuffle mask operand specifies, for each element of
				2874	the result vector, which element of the two input registers the result element
				2875	gets. The element selector may be undef (meaning "don't care") and the second
				2876	operand may be undef if performing a shuffle from only one vector.
				2877	</p>
				2878
				2879	<h5>Example:</h5>
				2880
				2881	<pre>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	2882	%result = shufflevector <4 x i32> %v1, <4 x i32> %v2,
Jeff Cohen	6f1cc77	2007-04-22 01:17:39 +0000	[diff] [blame]	2883	<4 x i32> <i32 0, i32 4, i32 1, i32 5> <i>; yields <4 x i32></i>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	2884	%result = shufflevector <4 x i32> %v1, <4 x i32> undef,
				2885	<4 x i32> <i32 0, i32 1, i32 2, i32 3> <i>; yields <4 x i32></i> - Identity shuffle.
Chris Lattner	3df241e	2006-04-08 23:07:04 +0000	[diff] [blame]	2886	</pre>
				2887	</div>
				2888
Tanya Lattner	0947429	2006-04-14 19:24:33 +0000	[diff] [blame]	2889
Chris Lattner	3df241e	2006-04-08 23:07:04 +0000	[diff] [blame]	2890	<!-- ======================================================================= -->
				2891	<div class="doc_subsection">
Dan Gohman	a334d5f	2008-05-12 23:51:09 +0000	[diff] [blame]	2892	<a name="aggregateops">Aggregate Operations</a>
				2893	</div>
				2894
				2895	<div class="doc_text">
				2896
				2897	<p>LLVM supports several instructions for working with aggregate values.
				2898	</p>
				2899
				2900	</div>
				2901
				2902	<!-- _______________________________________________________________________ -->
				2903	<div class="doc_subsubsection">
				2904	<a name="i_extractvalue">'<tt>extractvalue</tt>' Instruction</a>
				2905	</div>
				2906
				2907	<div class="doc_text">
				2908
				2909	<h5>Syntax:</h5>
				2910
				2911	<pre>
				2912	<result> = extractvalue <aggregate type> <val>, <idx>{, <idx>}*
				2913	</pre>
				2914
				2915	<h5>Overview:</h5>
				2916
				2917	<p>
Dan Gohman	c3dac5c	2008-05-13 18:16:06 +0000	[diff] [blame]	2918	The '<tt>extractvalue</tt>' instruction extracts the value of a struct field
				2919	or array element from an aggregate value.
Dan Gohman	a334d5f	2008-05-12 23:51:09 +0000	[diff] [blame]	2920	</p>
				2921
				2922
				2923	<h5>Arguments:</h5>
				2924
				2925	<p>
				2926	The first operand of an '<tt>extractvalue</tt>' instruction is a
				2927	value of <a href="#t_struct">struct</a> or <a href="#t_array">array</a>
Dan Gohman	c3dac5c	2008-05-13 18:16:06 +0000	[diff] [blame]	2928	type. The operands are constant indices to specify which value to extract
Dan Gohman	81a0c0b	2008-05-31 00:58:22 +0000	[diff] [blame]	2929	in a similar manner as indices in a
Dan Gohman	a334d5f	2008-05-12 23:51:09 +0000	[diff] [blame]	2930	'<tt><a href="#i_getelementptr">getelementptr</a></tt>' instruction.
				2931	</p>
				2932
				2933	<h5>Semantics:</h5>
				2934
				2935	<p>
				2936	The result is the value at the position in the aggregate specified by
				2937	the index operands.
				2938	</p>
				2939
				2940	<h5>Example:</h5>
				2941
				2942	<pre>
Dan Gohman	81a0c0b	2008-05-31 00:58:22 +0000	[diff] [blame]	2943	%result = extractvalue {i32, float} %agg, 0 <i>; yields i32</i>
Dan Gohman	a334d5f	2008-05-12 23:51:09 +0000	[diff] [blame]	2944	</pre>
				2945	</div>
				2946
				2947
				2948	<!-- _______________________________________________________________________ -->
				2949	<div class="doc_subsubsection">
				2950	<a name="i_insertvalue">'<tt>insertvalue</tt>' Instruction</a>
				2951	</div>
				2952
				2953	<div class="doc_text">
				2954
				2955	<h5>Syntax:</h5>
				2956
				2957	<pre>
Dan Gohman	81a0c0b	2008-05-31 00:58:22 +0000	[diff] [blame]	2958	<result> = insertvalue <aggregate type> <val>, <ty> <val>, <idx> <i>; yields <n x <ty>></i>
Dan Gohman	a334d5f	2008-05-12 23:51:09 +0000	[diff] [blame]	2959	</pre>
				2960
				2961	<h5>Overview:</h5>
				2962
				2963	<p>
				2964	The '<tt>insertvalue</tt>' instruction inserts a value
Dan Gohman	c3dac5c	2008-05-13 18:16:06 +0000	[diff] [blame]	2965	into a struct field or array element in an aggregate.
Dan Gohman	a334d5f	2008-05-12 23:51:09 +0000	[diff] [blame]	2966	</p>
				2967
				2968
				2969	<h5>Arguments:</h5>
				2970
				2971	<p>
				2972	The first operand of an '<tt>insertvalue</tt>' instruction is a
				2973	value of <a href="#t_struct">struct</a> or <a href="#t_array">array</a> type.
				2974	The second operand is a first-class value to insert.
Dan Gohman	c4b49eb	2008-05-23 21:53:15 +0000	[diff] [blame]	2975	The following operands are constant indices
Dan Gohman	81a0c0b	2008-05-31 00:58:22 +0000	[diff] [blame]	2976	indicating the position at which to insert the value in a similar manner as
Dan Gohman	c3dac5c	2008-05-13 18:16:06 +0000	[diff] [blame]	2977	indices in a
Dan Gohman	a334d5f	2008-05-12 23:51:09 +0000	[diff] [blame]	2978	'<tt><a href="#i_getelementptr">getelementptr</a></tt>' instruction.
				2979	The value to insert must have the same type as the value identified
Dan Gohman	c3dac5c	2008-05-13 18:16:06 +0000	[diff] [blame]	2980	by the indices.
Dan Gohman	a334d5f	2008-05-12 23:51:09 +0000	[diff] [blame]	2981
				2982	<h5>Semantics:</h5>
				2983
				2984	<p>
				2985	The result is an aggregate of the same type as <tt>val</tt>. Its
				2986	value is that of <tt>val</tt> except that the value at the position
Dan Gohman	c3dac5c	2008-05-13 18:16:06 +0000	[diff] [blame]	2987	specified by the indices is that of <tt>elt</tt>.
Dan Gohman	a334d5f	2008-05-12 23:51:09 +0000	[diff] [blame]	2988	</p>
				2989
				2990	<h5>Example:</h5>
				2991
				2992	<pre>
Dan Gohman	52bb2db	2008-06-23 15:26:37 +0000	[diff] [blame]	2993	%result = insertvalue {i32, float} %agg, i32 1, 0 <i>; yields {i32, float}</i>
Dan Gohman	a334d5f	2008-05-12 23:51:09 +0000	[diff] [blame]	2994	</pre>
				2995	</div>
				2996
				2997
				2998	<!-- ======================================================================= -->
				2999	<div class="doc_subsection">
Chris Lattner	884a970	2006-08-15 00:45:58 +0000	[diff] [blame]	3000	<a name="memoryops">Memory Access and Addressing Operations</a>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3001	</div>
				3002
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3003	<div class="doc_text">
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3004
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	3005	<p>A key design point of an SSA-based representation is how it
				3006	represents memory. In LLVM, no memory locations are in SSA form, which
				3007	makes things very simple. This section describes how to read, write,
John Criswell	9e2485c	2004-12-10 15:51:16 +0000	[diff] [blame]	3008	allocate, and free memory in LLVM.</p>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3009
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3010	</div>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3011
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3012	<!-- _______________________________________________________________________ -->
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3013	<div class="doc_subsubsection">
				3014	<a name="i_malloc">'<tt>malloc</tt>' Instruction</a>
				3015	</div>
				3016
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3017	<div class="doc_text">
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3018
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3019	<h5>Syntax:</h5>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3020
				3021	<pre>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3022	<result> = malloc <type>[, i32 <NumElements>][, align <alignment>] <i>; yields {type*}:result</i>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3023	</pre>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3024
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3025	<h5>Overview:</h5>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3026
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	3027	<p>The '<tt>malloc</tt>' instruction allocates memory from the system
Christopher Lamb	303dae9	2007-12-17 01:00:21 +0000	[diff] [blame]	3028	heap and returns a pointer to it. The object is always allocated in the generic
				3029	address space (address space zero).</p>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3030
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3031	<h5>Arguments:</h5>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3032
				3033	<p>The '<tt>malloc</tt>' instruction allocates
				3034	<tt>sizeof(<type>)*NumElements</tt>
John Criswell	6e4ca61	2004-02-24 16:13:56 +0000	[diff] [blame]	3035	bytes of memory from the operating system and returns a pointer of the
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3036	appropriate type to the program. If "NumElements" is specified, it is the
Gabor Greif	1acd2ee	2008-02-09 22:24:34 +0000	[diff] [blame]	3037	number of elements allocated, otherwise "NumElements" is defaulted to be one.
Chris Lattner	4316dec	2008-04-02 00:38:26 +0000	[diff] [blame]	3038	If a constant alignment is specified, the value result of the allocation is guaranteed to
Gabor Greif	1acd2ee	2008-02-09 22:24:34 +0000	[diff] [blame]	3039	be aligned to at least that boundary. If not specified, or if zero, the target can
				3040	choose to align the allocation on any convenient boundary.</p>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3041
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3042	<p>'<tt>type</tt>' must be a sized type.</p>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3043
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3044	<h5>Semantics:</h5>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3045
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	3046	<p>Memory is allocated using the system "<tt>malloc</tt>" function, and
Chris Lattner	72ed200	2008-04-19 21:01:16 +0000	[diff] [blame]	3047	a pointer is returned. The result of a zero byte allocattion is undefined. The
				3048	result is null if there is insufficient memory available.</p>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3049
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3050	<h5>Example:</h5>
				3051
				3052	<pre>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3053	%array = malloc [4 x i8 ] <i>; yields {[%4 x i8]*}:array</i>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3054
Bill Wendling	aac388b	2007-05-29 09:42:13 +0000	[diff] [blame]	3055	%size = <a href="#i_add">add</a> i32 2, 2 <i>; yields {i32}:size = i32 4</i>
				3056	%array1 = malloc i8, i32 4 <i>; yields {i8*}:array1</i>
				3057	%array2 = malloc [12 x i8], i32 %size <i>; yields {[12 x i8]*}:array2</i>
				3058	%array3 = malloc i32, i32 4, align 1024 <i>; yields {i32*}:array3</i>
				3059	%array4 = malloc i32, align 1024 <i>; yields {i32*}:array4</i>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3060	</pre>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3061	</div>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3062
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3063	<!-- _______________________________________________________________________ -->
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3064	<div class="doc_subsubsection">
				3065	<a name="i_free">'<tt>free</tt>' Instruction</a>
				3066	</div>
				3067
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3068	<div class="doc_text">
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3069
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3070	<h5>Syntax:</h5>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3071
				3072	<pre>
				3073	free <type> <value> <i>; yields {void}</i>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3074	</pre>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3075
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3076	<h5>Overview:</h5>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3077
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	3078	<p>The '<tt>free</tt>' instruction returns memory back to the unused
John Criswell	c1f786c	2005-05-13 22:25:59 +0000	[diff] [blame]	3079	memory heap to be reallocated in the future.</p>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3080
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3081	<h5>Arguments:</h5>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3082
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	3083	<p>'<tt>value</tt>' shall be a pointer value that points to a value
				3084	that was allocated with the '<tt><a href="#i_malloc">malloc</a></tt>'
				3085	instruction.</p>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3086
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3087	<h5>Semantics:</h5>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3088
John Criswell	9e2485c	2004-12-10 15:51:16 +0000	[diff] [blame]	3089	<p>Access to the memory pointed to by the pointer is no longer defined
Chris Lattner	e0db56d	2008-04-19 22:41:32 +0000	[diff] [blame]	3090	after this instruction executes. If the pointer is null, the operation
				3091	is a noop.</p>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3092
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3093	<h5>Example:</h5>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3094
				3095	<pre>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3096	%array = <a href="#i_malloc">malloc</a> [4 x i8] <i>; yields {[4 x i8]*}:array</i>
				3097	free [4 x i8]* %array
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3098	</pre>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3099	</div>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3100
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3101	<!-- _______________________________________________________________________ -->
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3102	<div class="doc_subsubsection">
				3103	<a name="i_alloca">'<tt>alloca</tt>' Instruction</a>
				3104	</div>
				3105
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3106	<div class="doc_text">
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3107
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3108	<h5>Syntax:</h5>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3109
				3110	<pre>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3111	<result> = alloca <type>[, i32 <NumElements>][, align <alignment>] <i>; yields {type*}:result</i>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3112	</pre>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3113
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3114	<h5>Overview:</h5>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3115
Jeff Cohen	6f1cc77	2007-04-22 01:17:39 +0000	[diff] [blame]	3116	<p>The '<tt>alloca</tt>' instruction allocates memory on the stack frame of the
				3117	currently executing function, to be automatically released when this function
Christopher Lamb	303dae9	2007-12-17 01:00:21 +0000	[diff] [blame]	3118	returns to its caller. The object is always allocated in the generic address
				3119	space (address space zero).</p>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3120
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3121	<h5>Arguments:</h5>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3122
John Criswell	9e2485c	2004-12-10 15:51:16 +0000	[diff] [blame]	3123	<p>The '<tt>alloca</tt>' instruction allocates <tt>sizeof(<type>)*NumElements</tt>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	3124	bytes of memory on the runtime stack, returning a pointer of the
Gabor Greif	1acd2ee	2008-02-09 22:24:34 +0000	[diff] [blame]	3125	appropriate type to the program. If "NumElements" is specified, it is the
				3126	number of elements allocated, otherwise "NumElements" is defaulted to be one.
Chris Lattner	4316dec	2008-04-02 00:38:26 +0000	[diff] [blame]	3127	If a constant alignment is specified, the value result of the allocation is guaranteed
Gabor Greif	1acd2ee	2008-02-09 22:24:34 +0000	[diff] [blame]	3128	to be aligned to at least that boundary. If not specified, or if zero, the target
				3129	can choose to align the allocation on any convenient boundary.</p>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3130
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3131	<p>'<tt>type</tt>' may be any sized type.</p>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3132
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3133	<h5>Semantics:</h5>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3134
Chris Lattner	72ed200	2008-04-19 21:01:16 +0000	[diff] [blame]	3135	<p>Memory is allocated; a pointer is returned. The operation is undefiend if
				3136	there is insufficient stack space for the allocation. '<tt>alloca</tt>'d
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	3137	memory is automatically released when the function returns. The '<tt>alloca</tt>'
				3138	instruction is commonly used to represent automatic variables that must
				3139	have an address available. When the function returns (either with the <tt><a
John Criswell	dae2e93	2005-05-12 16:55:34 +0000	[diff] [blame]	3140	href="#i_ret">ret</a></tt> or <tt><a href="#i_unwind">unwind</a></tt>
Chris Lattner	4316dec	2008-04-02 00:38:26 +0000	[diff] [blame]	3141	instructions), the memory is reclaimed. Allocating zero bytes
				3142	is legal, but the result is undefined.</p>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3143
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3144	<h5>Example:</h5>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3145
				3146	<pre>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3147	%ptr = alloca i32 <i>; yields {i32*}:ptr</i>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	3148	%ptr = alloca i32, i32 4 <i>; yields {i32*}:ptr</i>
				3149	%ptr = alloca i32, i32 4, align 1024 <i>; yields {i32*}:ptr</i>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3150	%ptr = alloca i32, align 1024 <i>; yields {i32*}:ptr</i>
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3151	</pre>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3152	</div>
Chris Lattner	2cbdc45	2005-11-06 08:02:57 +0000	[diff] [blame]	3153
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3154	<!-- _______________________________________________________________________ -->
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	3155	<div class="doc_subsubsection"> <a name="i_load">'<tt>load</tt>'
				3156	Instruction</a> </div>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3157	<div class="doc_text">
Chris Lattner	2b7d320	2002-05-06 03:03:22 +0000	[diff] [blame]	3158	<h5>Syntax:</h5>
Christopher Lamb	2330e4d	2007-04-21 08:16:25 +0000	[diff] [blame]	3159	<pre> <result> = load <ty>* <pointer>[, align <alignment>]<br> <result> = volatile load <ty>* <pointer>[, align <alignment>]<br></pre>
Chris Lattner	2b7d320	2002-05-06 03:03:22 +0000	[diff] [blame]	3160	<h5>Overview:</h5>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3161	<p>The '<tt>load</tt>' instruction is used to read from memory.</p>
Chris Lattner	2b7d320	2002-05-06 03:03:22 +0000	[diff] [blame]	3162	<h5>Arguments:</h5>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	3163	<p>The argument to the '<tt>load</tt>' instruction specifies the memory
John Criswell	0ec250c	2005-10-24 16:17:18 +0000	[diff] [blame]	3164	address from which to load. The pointer must point to a <a
Chris Lattner	e53e508	2004-06-03 22:57:15 +0000	[diff] [blame]	3165	href="#t_firstclass">first class</a> type. If the <tt>load</tt> is
John Criswell	0ec250c	2005-10-24 16:17:18 +0000	[diff] [blame]	3166	marked as <tt>volatile</tt>, then the optimizer is not allowed to modify
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	3167	the number or order of execution of this <tt>load</tt> with other
				3168	volatile <tt>load</tt> and <tt><a href="#i_store">store</a></tt>
				3169	instructions. </p>
Chris Lattner	a31d1d7	2008-01-06 21:04:43 +0000	[diff] [blame]	3170	<p>
Chris Lattner	4316dec	2008-04-02 00:38:26 +0000	[diff] [blame]	3171	The optional constant "align" argument specifies the alignment of the operation
Chris Lattner	a31d1d7	2008-01-06 21:04:43 +0000	[diff] [blame]	3172	(that is, the alignment of the memory address). A value of 0 or an
				3173	omitted "align" argument means that the operation has the preferential
				3174	alignment for the target. It is the responsibility of the code emitter
				3175	to ensure that the alignment information is correct. Overestimating
				3176	the alignment results in an undefined behavior. Underestimating the
				3177	alignment may produce less efficient code. An alignment of 1 is always
				3178	safe.
				3179	</p>
Chris Lattner	2b7d320	2002-05-06 03:03:22 +0000	[diff] [blame]	3180	<h5>Semantics:</h5>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3181	<p>The location of memory pointed to is loaded.</p>
Chris Lattner	2b7d320	2002-05-06 03:03:22 +0000	[diff] [blame]	3182	<h5>Examples:</h5>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3183	<pre> %ptr = <a href="#i_alloca">alloca</a> i32 <i>; yields {i32*}:ptr</i>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	3184	<a
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3185	href="#i_store">store</a> i32 3, i32* %ptr <i>; yields {void}</i>
				3186	%val = load i32* %ptr <i>; yields {i32}:val = i32 3</i>
Chris Lattner	2b7d320	2002-05-06 03:03:22 +0000	[diff] [blame]	3187	</pre>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3188	</div>
Chris Lattner	2b7d320	2002-05-06 03:03:22 +0000	[diff] [blame]	3189	<!-- _______________________________________________________________________ -->
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	3190	<div class="doc_subsubsection"> <a name="i_store">'<tt>store</tt>'
				3191	Instruction</a> </div>
Reid Spencer	035ab57	2006-11-09 21:18:01 +0000	[diff] [blame]	3192	<div class="doc_text">
Chris Lattner	2b7d320	2002-05-06 03:03:22 +0000	[diff] [blame]	3193	<h5>Syntax:</h5>
Christopher Lamb	2330e4d	2007-04-21 08:16:25 +0000	[diff] [blame]	3194	<pre> store <ty> <value>, <ty>* <pointer>[, align <alignment>] <i>; yields {void}</i>
				3195	volatile store <ty> <value>, <ty>* <pointer>[, align <alignment>] <i>; yields {void}</i>
Chris Lattner	2b7d320	2002-05-06 03:03:22 +0000	[diff] [blame]	3196	</pre>
Chris Lattner	2b7d320	2002-05-06 03:03:22 +0000	[diff] [blame]	3197	<h5>Overview:</h5>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3198	<p>The '<tt>store</tt>' instruction is used to write to memory.</p>
Chris Lattner	2b7d320	2002-05-06 03:03:22 +0000	[diff] [blame]	3199	<h5>Arguments:</h5>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	3200	<p>There are two arguments to the '<tt>store</tt>' instruction: a value
Jeff Cohen	6f1cc77	2007-04-22 01:17:39 +0000	[diff] [blame]	3201	to store and an address at which to store it. The type of the '<tt><pointer></tt>'
Chris Lattner	4316dec	2008-04-02 00:38:26 +0000	[diff] [blame]	3202	operand must be a pointer to the <a href="#t_firstclass">first class</a> type
				3203	of the '<tt><value></tt>'
John Criswell	c1f786c	2005-05-13 22:25:59 +0000	[diff] [blame]	3204	operand. If the <tt>store</tt> is marked as <tt>volatile</tt>, then the
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	3205	optimizer is not allowed to modify the number or order of execution of
				3206	this <tt>store</tt> with other volatile <tt>load</tt> and <tt><a
				3207	href="#i_store">store</a></tt> instructions.</p>
Chris Lattner	a31d1d7	2008-01-06 21:04:43 +0000	[diff] [blame]	3208	<p>
Chris Lattner	4316dec	2008-04-02 00:38:26 +0000	[diff] [blame]	3209	The optional constant "align" argument specifies the alignment of the operation
Chris Lattner	a31d1d7	2008-01-06 21:04:43 +0000	[diff] [blame]	3210	(that is, the alignment of the memory address). A value of 0 or an
				3211	omitted "align" argument means that the operation has the preferential
				3212	alignment for the target. It is the responsibility of the code emitter
				3213	to ensure that the alignment information is correct. Overestimating
				3214	the alignment results in an undefined behavior. Underestimating the
				3215	alignment may produce less efficient code. An alignment of 1 is always
				3216	safe.
				3217	</p>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	3218	<h5>Semantics:</h5>
				3219	<p>The contents of memory are updated to contain '<tt><value></tt>'
				3220	at the location specified by the '<tt><pointer></tt>' operand.</p>
Chris Lattner	2b7d320	2002-05-06 03:03:22 +0000	[diff] [blame]	3221	<h5>Example:</h5>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3222	<pre> %ptr = <a href="#i_alloca">alloca</a> i32 <i>; yields {i32*}:ptr</i>
Bill Wendling	8c6c72d	2007-10-22 05:10:05 +0000	[diff] [blame]	3223	store i32 3, i32* %ptr <i>; yields {void}</i>
				3224	%val = <a href="#i_load">load</a> i32* %ptr <i>; yields {i32}:val = i32 3</i>
Chris Lattner	2b7d320	2002-05-06 03:03:22 +0000	[diff] [blame]	3225	</pre>
Reid Spencer	47ce179	2006-11-09 21:15:49 +0000	[diff] [blame]	3226	</div>
				3227
Chris Lattner	2b7d320	2002-05-06 03:03:22 +0000	[diff] [blame]	3228	<!-- _______________________________________________________________________ -->
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3229	<div class="doc_subsubsection">
				3230	<a name="i_getelementptr">'<tt>getelementptr</tt>' Instruction</a>
				3231	</div>
				3232
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3233	<div class="doc_text">
Chris Lattner	7faa883	2002-04-14 06:13:44 +0000	[diff] [blame]	3234	<h5>Syntax:</h5>
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3235	<pre>
				3236	<result> = getelementptr <ty>* <ptrval>{, <ty> <idx>}*
				3237	</pre>
				3238
Chris Lattner	7faa883	2002-04-14 06:13:44 +0000	[diff] [blame]	3239	<h5>Overview:</h5>
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3240
				3241	<p>
				3242	The '<tt>getelementptr</tt>' instruction is used to get the address of a
				3243	subelement of an aggregate data structure.</p>
				3244
Chris Lattner	7faa883	2002-04-14 06:13:44 +0000	[diff] [blame]	3245	<h5>Arguments:</h5>
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3246
Reid Spencer	85f5b5b	2006-12-04 21:29:24 +0000	[diff] [blame]	3247	<p>This instruction takes a list of integer operands that indicate what
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3248	elements of the aggregate object to index to. The actual types of the arguments
				3249	provided depend on the type of the first pointer argument. The
				3250	'<tt>getelementptr</tt>' instruction is used to index down through the type
John Criswell	fc6b895	2005-05-16 16:17:45 +0000	[diff] [blame]	3251	levels of a structure or to a specific index in an array. When indexing into a
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3252	structure, only <tt>i32</tt> integer constants are allowed. When indexing
Chris Lattner	05d6709	2008-04-24 05:59:56 +0000	[diff] [blame]	3253	into an array or pointer, only integers of 32 or 64 bits are allowed; 32-bit
				3254	values will be sign extended to 64-bits if required.</p>
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3255
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	3256	<p>For example, let's consider a C code fragment and how it gets
				3257	compiled to LLVM:</p>
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3258
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	3259	<div class="doc_code">
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3260	<pre>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	3261	struct RT {
				3262	char A;
Chris Lattner	cabc846	2007-05-29 15:43:56 +0000	[diff] [blame]	3263	int B[10][20];
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	3264	char C;
				3265	};
				3266	struct ST {
Chris Lattner	cabc846	2007-05-29 15:43:56 +0000	[diff] [blame]	3267	int X;
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	3268	double Y;
				3269	struct RT Z;
				3270	};
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3271
Chris Lattner	cabc846	2007-05-29 15:43:56 +0000	[diff] [blame]	3272	int foo(struct ST s) {
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	3273	return &s[1].Z.B[5][13];
				3274	}
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3275	</pre>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	3276	</div>
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3277
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3278	<p>The LLVM code generated by the GCC frontend is:</p>
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3279
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	3280	<div class="doc_code">
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3281	<pre>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	3282	%RT = type { i8 , [10 x [20 x i32]], i8 }
				3283	%ST = type { i32, double, %RT }
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3284
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	3285	define i32* %foo(%ST* %s) {
				3286	entry:
				3287	%reg = getelementptr %ST* %s, i32 1, i32 2, i32 1, i32 5, i32 13
				3288	ret i32* %reg
				3289	}
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3290	</pre>
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	3291	</div>
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3292
Chris Lattner	7faa883	2002-04-14 06:13:44 +0000	[diff] [blame]	3293	<h5>Semantics:</h5>
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3294
				3295	<p>The index types specified for the '<tt>getelementptr</tt>' instruction depend
John Criswell	c1f786c	2005-05-13 22:25:59 +0000	[diff] [blame]	3296	on the pointer type that is being indexed into. <a href="#t_pointer">Pointer</a>
Reid Spencer	85f5b5b	2006-12-04 21:29:24 +0000	[diff] [blame]	3297	and <a href="#t_array">array</a> types can use a 32-bit or 64-bit
Reid Spencer	42ddd84	2006-12-03 16:53:48 +0000	[diff] [blame]	3298	<a href="#t_integer">integer</a> type but the value will always be sign extended
Chris Lattner	4316dec	2008-04-02 00:38:26 +0000	[diff] [blame]	3299	to 64-bits. <a href="#t_struct">Structure</a> and <a href="#t_pstruct">packed
				3300	structure</a> types require <tt>i32</tt> <b>constants</b>.</p>
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3301
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3302	<p>In the example above, the first index is indexing into the '<tt>%ST*</tt>'
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3303	type, which is a pointer, yielding a '<tt>%ST</tt>' = '<tt>{ i32, double, %RT
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3304	}</tt>' type, a structure. The second index indexes into the third element of
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3305	the structure, yielding a '<tt>%RT</tt>' = '<tt>{ i8 , [10 x [20 x i32]],
				3306	i8 }</tt>' type, another structure. The third index indexes into the second
				3307	element of the structure, yielding a '<tt>[10 x [20 x i32]]</tt>' type, an
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3308	array. The two dimensions of the array are subscripted into, yielding an
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3309	'<tt>i32</tt>' type. The '<tt>getelementptr</tt>' instruction returns a pointer
				3310	to this element, thus computing a value of '<tt>i32*</tt>' type.</p>
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3311
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	3312	<p>Note that it is perfectly legal to index partially through a
				3313	structure, returning a pointer to an inner element. Because of this,
				3314	the LLVM code for the given testcase is equivalent to:</p>
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3315
				3316	<pre>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3317	define i32* %foo(%ST* %s) {
				3318	%t1 = getelementptr %ST* %s, i32 1 <i>; yields %ST*:%t1</i>
Jeff Cohen	6f1cc77	2007-04-22 01:17:39 +0000	[diff] [blame]	3319	%t2 = getelementptr %ST* %t1, i32 0, i32 2 <i>; yields %RT*:%t2</i>
				3320	%t3 = getelementptr %RT* %t2, i32 0, i32 1 <i>; yields [10 x [20 x i32]]*:%t3</i>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3321	%t4 = getelementptr [10 x [20 x i32]]* %t3, i32 0, i32 5 <i>; yields [20 x i32]*:%t4</i>
				3322	%t5 = getelementptr [20 x i32]* %t4, i32 0, i32 13 <i>; yields i32*:%t5</i>
				3323	ret i32* %t5
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3324	}
Chris Lattner	6536cfe	2002-05-06 22:08:29 +0000	[diff] [blame]	3325	</pre>
Chris Lattner	e67a951	2005-06-24 17:22:57 +0000	[diff] [blame]	3326
				3327	<p>Note that it is undefined to access an array out of bounds: array and
				3328	pointer indexes must always be within the defined bounds of the array type.
Chris Lattner	05d6709	2008-04-24 05:59:56 +0000	[diff] [blame]	3329	The one exception for this rule is zero length arrays. These arrays are
Chris Lattner	e67a951	2005-06-24 17:22:57 +0000	[diff] [blame]	3330	defined to be accessible as variable length arrays, which requires access
				3331	beyond the zero'th element.</p>
				3332
Chris Lattner	884a970	2006-08-15 00:45:58 +0000	[diff] [blame]	3333	<p>The getelementptr instruction is often confusing. For some more insight
				3334	into how it works, see <a href="GetElementPtr.html">the getelementptr
				3335	FAQ</a>.</p>
				3336
Chris Lattner	7faa883	2002-04-14 06:13:44 +0000	[diff] [blame]	3337	<h5>Example:</h5>
Chris Lattner	e67a951	2005-06-24 17:22:57 +0000	[diff] [blame]	3338
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3339	<pre>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3340	<i>; yields [12 x i8]*:aptr</i>
				3341	%aptr = getelementptr {i32, [12 x i8]}* %sptr, i64 0, i32 1
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3342	</pre>
Chris Lattner	f74d5c7	2004-04-05 01:30:49 +0000	[diff] [blame]	3343	</div>
Reid Spencer	47ce179	2006-11-09 21:15:49 +0000	[diff] [blame]	3344
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	3345	<!-- ======================================================================= -->
Reid Spencer	2fd21e6	2006-11-08 01:18:52 +0000	[diff] [blame]	3346	<div class="doc_subsection"> <a name="convertops">Conversion Operations</a>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3347	</div>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3348	<div class="doc_text">
Reid Spencer	2fd21e6	2006-11-08 01:18:52 +0000	[diff] [blame]	3349	<p>The instructions in this category are the conversion instructions (casting)
				3350	which all take a single operand and a type. They perform various bit conversions
				3351	on the operand.</p>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3352	</div>
Chris Lattner	cc37aae	2004-03-12 05:50:16 +0000	[diff] [blame]	3353
Chris Lattner	6536cfe	2002-05-06 22:08:29 +0000	[diff] [blame]	3354	<!-- _______________________________________________________________________ -->
Chris Lattner	cc37aae	2004-03-12 05:50:16 +0000	[diff] [blame]	3355	<div class="doc_subsubsection">
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3356	<a name="i_trunc">'<tt>trunc .. to</tt>' Instruction</a>
				3357	</div>
				3358	<div class="doc_text">
				3359
				3360	<h5>Syntax:</h5>
				3361	<pre>
				3362	<result> = trunc <ty> <value> to <ty2> <i>; yields ty2</i>
				3363	</pre>
				3364
				3365	<h5>Overview:</h5>
				3366	<p>
				3367	The '<tt>trunc</tt>' instruction truncates its operand to the type <tt>ty2</tt>.
				3368	</p>
				3369
				3370	<h5>Arguments:</h5>
				3371	<p>
				3372	The '<tt>trunc</tt>' instruction takes a <tt>value</tt> to trunc, which must
				3373	be an <a href="#t_integer">integer</a> type, and a type that specifies the size
Chris Lattner	3b19d65	2007-01-15 01:54:13 +0000	[diff] [blame]	3374	and type of the result, which must be an <a href="#t_integer">integer</a>
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	3375	type. The bit size of <tt>value</tt> must be larger than the bit size of
				3376	<tt>ty2</tt>. Equal sized types are not allowed.</p>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3377
				3378	<h5>Semantics:</h5>
				3379	<p>
				3380	The '<tt>trunc</tt>' instruction truncates the high order bits in <tt>value</tt>
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	3381	and converts the remaining bits to <tt>ty2</tt>. Since the source size must be
				3382	larger than the destination size, <tt>trunc</tt> cannot be a <i>no-op cast</i>.
				3383	It will always truncate bits.</p>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3384
				3385	<h5>Example:</h5>
				3386	<pre>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3387	%X = trunc i32 257 to i8 <i>; yields i8:1</i>
Reid Spencer	c78f337	2007-01-12 03:35:51 +0000	[diff] [blame]	3388	%Y = trunc i32 123 to i1 <i>; yields i1:true</i>
				3389	%Y = trunc i32 122 to i1 <i>; yields i1:false</i>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3390	</pre>
				3391	</div>
				3392
				3393	<!-- _______________________________________________________________________ -->
				3394	<div class="doc_subsubsection">
				3395	<a name="i_zext">'<tt>zext .. to</tt>' Instruction</a>
				3396	</div>
				3397	<div class="doc_text">
				3398
				3399	<h5>Syntax:</h5>
				3400	<pre>
				3401	<result> = zext <ty> <value> to <ty2> <i>; yields ty2</i>
				3402	</pre>
				3403
				3404	<h5>Overview:</h5>
				3405	<p>The '<tt>zext</tt>' instruction zero extends its operand to type
				3406	<tt>ty2</tt>.</p>
				3407
				3408
				3409	<h5>Arguments:</h5>
				3410	<p>The '<tt>zext</tt>' instruction takes a value to cast, which must be of
Chris Lattner	3b19d65	2007-01-15 01:54:13 +0000	[diff] [blame]	3411	<a href="#t_integer">integer</a> type, and a type to cast it to, which must
				3412	also be of <a href="#t_integer">integer</a> type. The bit size of the
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	3413	<tt>value</tt> must be smaller than the bit size of the destination type,
				3414	<tt>ty2</tt>.</p>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3415
				3416	<h5>Semantics:</h5>
				3417	<p>The <tt>zext</tt> fills the high order bits of the <tt>value</tt> with zero
Chris Lattner	d1d2517	2007-05-24 19:13:27 +0000	[diff] [blame]	3418	bits until it reaches the size of the destination type, <tt>ty2</tt>.</p>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3419
Reid Spencer	b592952	2007-01-12 15:46:11 +0000	[diff] [blame]	3420	<p>When zero extending from i1, the result will always be either 0 or 1.</p>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3421
				3422	<h5>Example:</h5>
				3423	<pre>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3424	%X = zext i32 257 to i64 <i>; yields i64:257</i>
Reid Spencer	c78f337	2007-01-12 03:35:51 +0000	[diff] [blame]	3425	%Y = zext i1 true to i32 <i>; yields i32:1</i>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3426	</pre>
				3427	</div>
				3428
				3429	<!-- _______________________________________________________________________ -->
				3430	<div class="doc_subsubsection">
				3431	<a name="i_sext">'<tt>sext .. to</tt>' Instruction</a>
				3432	</div>
				3433	<div class="doc_text">
				3434
				3435	<h5>Syntax:</h5>
				3436	<pre>
				3437	<result> = sext <ty> <value> to <ty2> <i>; yields ty2</i>
				3438	</pre>
				3439
				3440	<h5>Overview:</h5>
				3441	<p>The '<tt>sext</tt>' sign extends <tt>value</tt> to the type <tt>ty2</tt>.</p>
				3442
				3443	<h5>Arguments:</h5>
				3444	<p>
				3445	The '<tt>sext</tt>' instruction takes a value to cast, which must be of
Chris Lattner	3b19d65	2007-01-15 01:54:13 +0000	[diff] [blame]	3446	<a href="#t_integer">integer</a> type, and a type to cast it to, which must
				3447	also be of <a href="#t_integer">integer</a> type. The bit size of the
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	3448	<tt>value</tt> must be smaller than the bit size of the destination type,
				3449	<tt>ty2</tt>.</p>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3450
				3451	<h5>Semantics:</h5>
				3452	<p>
				3453	The '<tt>sext</tt>' instruction performs a sign extension by copying the sign
				3454	bit (highest order bit) of the <tt>value</tt> until it reaches the bit size of
Chris Lattner	d1d2517	2007-05-24 19:13:27 +0000	[diff] [blame]	3455	the type <tt>ty2</tt>.</p>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3456
Reid Spencer	c78f337	2007-01-12 03:35:51 +0000	[diff] [blame]	3457	<p>When sign extending from i1, the extension always results in -1 or 0.</p>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3458
				3459	<h5>Example:</h5>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3460	<pre>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3461	%X = sext i8 -1 to i16 <i>; yields i16 :65535</i>
Reid Spencer	c78f337	2007-01-12 03:35:51 +0000	[diff] [blame]	3462	%Y = sext i1 true to i32 <i>; yields i32:-1</i>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3463	</pre>
				3464	</div>
				3465
				3466	<!-- _______________________________________________________________________ -->
				3467	<div class="doc_subsubsection">
Reid Spencer	3fa91b0	2006-11-09 21:48:10 +0000	[diff] [blame]	3468	<a name="i_fptrunc">'<tt>fptrunc .. to</tt>' Instruction</a>
				3469	</div>
				3470
				3471	<div class="doc_text">
				3472
				3473	<h5>Syntax:</h5>
				3474
				3475	<pre>
				3476	<result> = fptrunc <ty> <value> to <ty2> <i>; yields ty2</i>
				3477	</pre>
				3478
				3479	<h5>Overview:</h5>
				3480	<p>The '<tt>fptrunc</tt>' instruction truncates <tt>value</tt> to type
				3481	<tt>ty2</tt>.</p>
				3482
				3483
				3484	<h5>Arguments:</h5>
				3485	<p>The '<tt>fptrunc</tt>' instruction takes a <a href="#t_floating">floating
				3486	point</a> value to cast and a <a href="#t_floating">floating point</a> type to
				3487	cast it to. The size of <tt>value</tt> must be larger than the size of
				3488	<tt>ty2</tt>. This implies that <tt>fptrunc</tt> cannot be used to make a
				3489	<i>no-op cast</i>.</p>
				3490
				3491	<h5>Semantics:</h5>
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	3492	<p> The '<tt>fptrunc</tt>' instruction truncates a <tt>value</tt> from a larger
				3493	<a href="#t_floating">floating point</a> type to a smaller
				3494	<a href="#t_floating">floating point</a> type. If the value cannot fit within
				3495	the destination type, <tt>ty2</tt>, then the results are undefined.</p>
Reid Spencer	3fa91b0	2006-11-09 21:48:10 +0000	[diff] [blame]	3496
				3497	<h5>Example:</h5>
				3498	<pre>
				3499	%X = fptrunc double 123.0 to float <i>; yields float:123.0</i>
				3500	%Y = fptrunc double 1.0E+300 to float <i>; yields undefined</i>
				3501	</pre>
				3502	</div>
				3503
				3504	<!-- _______________________________________________________________________ -->
				3505	<div class="doc_subsubsection">
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3506	<a name="i_fpext">'<tt>fpext .. to</tt>' Instruction</a>
				3507	</div>
				3508	<div class="doc_text">
				3509
				3510	<h5>Syntax:</h5>
				3511	<pre>
				3512	<result> = fpext <ty> <value> to <ty2> <i>; yields ty2</i>
				3513	</pre>
				3514
				3515	<h5>Overview:</h5>
				3516	<p>The '<tt>fpext</tt>' extends a floating point <tt>value</tt> to a larger
				3517	floating point value.</p>
				3518
				3519	<h5>Arguments:</h5>
				3520	<p>The '<tt>fpext</tt>' instruction takes a
				3521	<a href="#t_floating">floating point</a> <tt>value</tt> to cast,
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	3522	and a <a href="#t_floating">floating point</a> type to cast it to. The source
				3523	type must be smaller than the destination type.</p>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3524
				3525	<h5>Semantics:</h5>
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	3526	<p>The '<tt>fpext</tt>' instruction extends the <tt>value</tt> from a smaller
Duncan Sands	8036ca4	2007-03-30 12:22:09 +0000	[diff] [blame]	3527	<a href="#t_floating">floating point</a> type to a larger
				3528	<a href="#t_floating">floating point</a> type. The <tt>fpext</tt> cannot be
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	3529	used to make a <i>no-op cast</i> because it always changes bits. Use
Reid Spencer	5c0ef47	2006-11-11 23:08:07 +0000	[diff] [blame]	3530	<tt>bitcast</tt> to make a <i>no-op cast</i> for a floating point cast.</p>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3531
				3532	<h5>Example:</h5>
				3533	<pre>
				3534	%X = fpext float 3.1415 to double <i>; yields double:3.1415</i>
				3535	%Y = fpext float 1.0 to float <i>; yields float:1.0 (no-op)</i>
				3536	</pre>
				3537	</div>
				3538
				3539	<!-- _______________________________________________________________________ -->
				3540	<div class="doc_subsubsection">
Reid Spencer	24d6da5	2007-01-21 00:29:26 +0000	[diff] [blame]	3541	<a name="i_fptoui">'<tt>fptoui .. to</tt>' Instruction</a>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3542	</div>
				3543	<div class="doc_text">
				3544
				3545	<h5>Syntax:</h5>
				3546	<pre>
Reid Spencer	1539a1c	2007-07-31 14:40:14 +0000	[diff] [blame]	3547	<result> = fptoui <ty> <value> to <ty2> <i>; yields ty2</i>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3548	</pre>
				3549
				3550	<h5>Overview:</h5>
Reid Spencer	1539a1c	2007-07-31 14:40:14 +0000	[diff] [blame]	3551	<p>The '<tt>fptoui</tt>' converts a floating point <tt>value</tt> to its
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3552	unsigned integer equivalent of type <tt>ty2</tt>.
				3553	</p>
				3554
				3555	<h5>Arguments:</h5>
Reid Spencer	1539a1c	2007-07-31 14:40:14 +0000	[diff] [blame]	3556	<p>The '<tt>fptoui</tt>' instruction takes a value to cast, which must be a
Nate Begeman	b348d18	2007-11-17 03:58:34 +0000	[diff] [blame]	3557	scalar or vector <a href="#t_floating">floating point</a> value, and a type
				3558	to cast it to <tt>ty2</tt>, which must be an <a href="#t_integer">integer</a>
				3559	type. If <tt>ty</tt> is a vector floating point type, <tt>ty2</tt> must be a
				3560	vector integer type with the same number of elements as <tt>ty</tt></p>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3561
				3562	<h5>Semantics:</h5>
Reid Spencer	1539a1c	2007-07-31 14:40:14 +0000	[diff] [blame]	3563	<p> The '<tt>fptoui</tt>' instruction converts its
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3564	<a href="#t_floating">floating point</a> operand into the nearest (rounding
				3565	towards zero) unsigned integer value. If the value cannot fit in <tt>ty2</tt>,
				3566	the results are undefined.</p>
				3567
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3568	<h5>Example:</h5>
				3569	<pre>
Reid Spencer	1539a1c	2007-07-31 14:40:14 +0000	[diff] [blame]	3570	%X = fptoui double 123.0 to i32 <i>; yields i32:123</i>
Chris Lattner	8851904	2007-09-22 03:17:52 +0000	[diff] [blame]	3571	%Y = fptoui float 1.0E+300 to i1 <i>; yields undefined:1</i>
Reid Spencer	1539a1c	2007-07-31 14:40:14 +0000	[diff] [blame]	3572	%X = fptoui float 1.04E+17 to i8 <i>; yields undefined:1</i>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3573	</pre>
				3574	</div>
				3575
				3576	<!-- _______________________________________________________________________ -->
				3577	<div class="doc_subsubsection">
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	3578	<a name="i_fptosi">'<tt>fptosi .. to</tt>' Instruction</a>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3579	</div>
				3580	<div class="doc_text">
				3581
				3582	<h5>Syntax:</h5>
				3583	<pre>
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	3584	<result> = fptosi <ty> <value> to <ty2> <i>; yields ty2</i>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3585	</pre>
				3586
				3587	<h5>Overview:</h5>
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	3588	<p>The '<tt>fptosi</tt>' instruction converts
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3589	<a href="#t_floating">floating point</a> <tt>value</tt> to type <tt>ty2</tt>.
Chris Lattner	cc37aae	2004-03-12 05:50:16 +0000	[diff] [blame]	3590	</p>
				3591
Chris Lattner	6536cfe	2002-05-06 22:08:29 +0000	[diff] [blame]	3592	<h5>Arguments:</h5>
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	3593	<p> The '<tt>fptosi</tt>' instruction takes a value to cast, which must be a
Nate Begeman	b348d18	2007-11-17 03:58:34 +0000	[diff] [blame]	3594	scalar or vector <a href="#t_floating">floating point</a> value, and a type
				3595	to cast it to <tt>ty2</tt>, which must be an <a href="#t_integer">integer</a>
				3596	type. If <tt>ty</tt> is a vector floating point type, <tt>ty2</tt> must be a
				3597	vector integer type with the same number of elements as <tt>ty</tt></p>
Chris Lattner	cc37aae	2004-03-12 05:50:16 +0000	[diff] [blame]	3598
Chris Lattner	6536cfe	2002-05-06 22:08:29 +0000	[diff] [blame]	3599	<h5>Semantics:</h5>
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	3600	<p>The '<tt>fptosi</tt>' instruction converts its
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3601	<a href="#t_floating">floating point</a> operand into the nearest (rounding
				3602	towards zero) signed integer value. If the value cannot fit in <tt>ty2</tt>,
				3603	the results are undefined.</p>
Chris Lattner	cc37aae	2004-03-12 05:50:16 +0000	[diff] [blame]	3604
Chris Lattner	33ba0d9	2001-07-09 00:26:23 +0000	[diff] [blame]	3605	<h5>Example:</h5>
Chris Lattner	cc37aae	2004-03-12 05:50:16 +0000	[diff] [blame]	3606	<pre>
Reid Spencer	c78f337	2007-01-12 03:35:51 +0000	[diff] [blame]	3607	%X = fptosi double -123.0 to i32 <i>; yields i32:-123</i>
Chris Lattner	8851904	2007-09-22 03:17:52 +0000	[diff] [blame]	3608	%Y = fptosi float 1.0E-247 to i1 <i>; yields undefined:1</i>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3609	%X = fptosi float 1.04E+17 to i8 <i>; yields undefined:1</i>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3610	</pre>
				3611	</div>
				3612
				3613	<!-- _______________________________________________________________________ -->
				3614	<div class="doc_subsubsection">
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	3615	<a name="i_uitofp">'<tt>uitofp .. to</tt>' Instruction</a>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3616	</div>
				3617	<div class="doc_text">
				3618
				3619	<h5>Syntax:</h5>
				3620	<pre>
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	3621	<result> = uitofp <ty> <value> to <ty2> <i>; yields ty2</i>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3622	</pre>
				3623
				3624	<h5>Overview:</h5>
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	3625	<p>The '<tt>uitofp</tt>' instruction regards <tt>value</tt> as an unsigned
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3626	integer and converts that value to the <tt>ty2</tt> type.</p>
				3627
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3628	<h5>Arguments:</h5>
Nate Begeman	b348d18	2007-11-17 03:58:34 +0000	[diff] [blame]	3629	<p>The '<tt>uitofp</tt>' instruction takes a value to cast, which must be a
				3630	scalar or vector <a href="#t_integer">integer</a> value, and a type to cast it
				3631	to <tt>ty2</tt>, which must be an <a href="#t_floating">floating point</a>
				3632	type. If <tt>ty</tt> is a vector integer type, <tt>ty2</tt> must be a vector
				3633	floating point type with the same number of elements as <tt>ty</tt></p>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3634
				3635	<h5>Semantics:</h5>
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	3636	<p>The '<tt>uitofp</tt>' instruction interprets its operand as an unsigned
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3637	integer quantity and converts it to the corresponding floating point value. If
Jeff Cohen	cb75731	2007-04-22 14:56:37 +0000	[diff] [blame]	3638	the value cannot fit in the floating point value, the results are undefined.</p>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3639
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3640	<h5>Example:</h5>
				3641	<pre>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3642	%X = uitofp i32 257 to float <i>; yields float:257.0</i>
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	3643	%Y = uitofp i8 -1 to double <i>; yields double:255.0</i>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3644	</pre>
				3645	</div>
				3646
				3647	<!-- _______________________________________________________________________ -->
				3648	<div class="doc_subsubsection">
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	3649	<a name="i_sitofp">'<tt>sitofp .. to</tt>' Instruction</a>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3650	</div>
				3651	<div class="doc_text">
				3652
				3653	<h5>Syntax:</h5>
				3654	<pre>
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	3655	<result> = sitofp <ty> <value> to <ty2> <i>; yields ty2</i>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3656	</pre>
				3657
				3658	<h5>Overview:</h5>
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	3659	<p>The '<tt>sitofp</tt>' instruction regards <tt>value</tt> as a signed
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3660	integer and converts that value to the <tt>ty2</tt> type.</p>
				3661
				3662	<h5>Arguments:</h5>
Nate Begeman	b348d18	2007-11-17 03:58:34 +0000	[diff] [blame]	3663	<p>The '<tt>sitofp</tt>' instruction takes a value to cast, which must be a
				3664	scalar or vector <a href="#t_integer">integer</a> value, and a type to cast it
				3665	to <tt>ty2</tt>, which must be an <a href="#t_floating">floating point</a>
				3666	type. If <tt>ty</tt> is a vector integer type, <tt>ty2</tt> must be a vector
				3667	floating point type with the same number of elements as <tt>ty</tt></p>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3668
				3669	<h5>Semantics:</h5>
Reid Spencer	d444879	2006-11-09 23:03:26 +0000	[diff] [blame]	3670	<p>The '<tt>sitofp</tt>' instruction interprets its operand as a signed
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3671	integer quantity and converts it to the corresponding floating point value. If
Jeff Cohen	cb75731	2007-04-22 14:56:37 +0000	[diff] [blame]	3672	the value cannot fit in the floating point value, the results are undefined.</p>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3673
				3674	<h5>Example:</h5>
				3675	<pre>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3676	%X = sitofp i32 257 to float <i>; yields float:257.0</i>
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	3677	%Y = sitofp i8 -1 to double <i>; yields double:-1.0</i>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3678	</pre>
				3679	</div>
				3680
				3681	<!-- _______________________________________________________________________ -->
				3682	<div class="doc_subsubsection">
Reid Spencer	7267925	2006-11-11 21:00:47 +0000	[diff] [blame]	3683	<a name="i_ptrtoint">'<tt>ptrtoint .. to</tt>' Instruction</a>
				3684	</div>
				3685	<div class="doc_text">
				3686
				3687	<h5>Syntax:</h5>
				3688	<pre>
				3689	<result> = ptrtoint <ty> <value> to <ty2> <i>; yields ty2</i>
				3690	</pre>
				3691
				3692	<h5>Overview:</h5>
				3693	<p>The '<tt>ptrtoint</tt>' instruction converts the pointer <tt>value</tt> to
				3694	the integer type <tt>ty2</tt>.</p>
				3695
				3696	<h5>Arguments:</h5>
				3697	<p>The '<tt>ptrtoint</tt>' instruction takes a <tt>value</tt> to cast, which
Duncan Sands	8036ca4	2007-03-30 12:22:09 +0000	[diff] [blame]	3698	must be a <a href="#t_pointer">pointer</a> value, and a type to cast it to
Reid Spencer	7267925	2006-11-11 21:00:47 +0000	[diff] [blame]	3699	<tt>ty2</tt>, which must be an <a href="#t_integer">integer</a> type.
				3700
				3701	<h5>Semantics:</h5>
				3702	<p>The '<tt>ptrtoint</tt>' instruction converts <tt>value</tt> to integer type
				3703	<tt>ty2</tt> by interpreting the pointer value as an integer and either
				3704	truncating or zero extending that value to the size of the integer type. If
				3705	<tt>value</tt> is smaller than <tt>ty2</tt> then a zero extension is done. If
				3706	<tt>value</tt> is larger than <tt>ty2</tt> then a truncation is done. If they
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	3707	are the same size, then nothing is done (<i>no-op cast</i>) other than a type
				3708	change.</p>
Reid Spencer	7267925	2006-11-11 21:00:47 +0000	[diff] [blame]	3709
				3710	<h5>Example:</h5>
				3711	<pre>
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	3712	%X = ptrtoint i32* %X to i8 <i>; yields truncation on 32-bit architecture</i>
				3713	%Y = ptrtoint i32* %x to i64 <i>; yields zero extension on 32-bit architecture</i>
Reid Spencer	7267925	2006-11-11 21:00:47 +0000	[diff] [blame]	3714	</pre>
				3715	</div>
				3716
				3717	<!-- _______________________________________________________________________ -->
				3718	<div class="doc_subsubsection">
				3719	<a name="i_inttoptr">'<tt>inttoptr .. to</tt>' Instruction</a>
				3720	</div>
				3721	<div class="doc_text">
				3722
				3723	<h5>Syntax:</h5>
				3724	<pre>
				3725	<result> = inttoptr <ty> <value> to <ty2> <i>; yields ty2</i>
				3726	</pre>
				3727
				3728	<h5>Overview:</h5>
				3729	<p>The '<tt>inttoptr</tt>' instruction converts an integer <tt>value</tt> to
				3730	a pointer type, <tt>ty2</tt>.</p>
				3731
				3732	<h5>Arguments:</h5>
Duncan Sands	8036ca4	2007-03-30 12:22:09 +0000	[diff] [blame]	3733	<p>The '<tt>inttoptr</tt>' instruction takes an <a href="#t_integer">integer</a>
Reid Spencer	7267925	2006-11-11 21:00:47 +0000	[diff] [blame]	3734	value to cast, and a type to cast it to, which must be a
Anton Korobeynikov	7f70559	2007-01-12 19:20:47 +0000	[diff] [blame]	3735	<a href="#t_pointer">pointer</a> type.
Reid Spencer	7267925	2006-11-11 21:00:47 +0000	[diff] [blame]	3736
				3737	<h5>Semantics:</h5>
				3738	<p>The '<tt>inttoptr</tt>' instruction converts <tt>value</tt> to type
				3739	<tt>ty2</tt> by applying either a zero extension or a truncation depending on
				3740	the size of the integer <tt>value</tt>. If <tt>value</tt> is larger than the
				3741	size of a pointer then a truncation is done. If <tt>value</tt> is smaller than
				3742	the size of a pointer then a zero extension is done. If they are the same size,
				3743	nothing is done (<i>no-op cast</i>).</p>
				3744
				3745	<h5>Example:</h5>
				3746	<pre>
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	3747	%X = inttoptr i32 255 to i32* <i>; yields zero extension on 64-bit architecture</i>
				3748	%X = inttoptr i32 255 to i32* <i>; yields no-op on 32-bit architecture</i>
				3749	%Y = inttoptr i64 0 to i32* <i>; yields truncation on 32-bit architecture</i>
Reid Spencer	7267925	2006-11-11 21:00:47 +0000	[diff] [blame]	3750	</pre>
				3751	</div>
				3752
				3753	<!-- _______________________________________________________________________ -->
				3754	<div class="doc_subsubsection">
Reid Spencer	5c0ef47	2006-11-11 23:08:07 +0000	[diff] [blame]	3755	<a name="i_bitcast">'<tt>bitcast .. to</tt>' Instruction</a>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3756	</div>
				3757	<div class="doc_text">
				3758
				3759	<h5>Syntax:</h5>
				3760	<pre>
Reid Spencer	5c0ef47	2006-11-11 23:08:07 +0000	[diff] [blame]	3761	<result> = bitcast <ty> <value> to <ty2> <i>; yields ty2</i>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3762	</pre>
				3763
				3764	<h5>Overview:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	3765
Reid Spencer	5c0ef47	2006-11-11 23:08:07 +0000	[diff] [blame]	3766	<p>The '<tt>bitcast</tt>' instruction converts <tt>value</tt> to type
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3767	<tt>ty2</tt> without changing any bits.</p>
				3768
				3769	<h5>Arguments:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	3770
Reid Spencer	5c0ef47	2006-11-11 23:08:07 +0000	[diff] [blame]	3771	<p>The '<tt>bitcast</tt>' instruction takes a value to cast, which must be
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3772	a first class value, and a type to cast it to, which must also be a <a
				3773	href="#t_firstclass">first class</a> type. The bit sizes of <tt>value</tt>
Reid Spencer	19b569f	2007-01-09 20:08:58 +0000	[diff] [blame]	3774	and the destination type, <tt>ty2</tt>, must be identical. If the source
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	3775	type is a pointer, the destination type must also be a pointer. This
				3776	instruction supports bitwise conversion of vectors to integers and to vectors
				3777	of other types (as long as they have the same size).</p>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3778
				3779	<h5>Semantics:</h5>
Reid Spencer	5c0ef47	2006-11-11 23:08:07 +0000	[diff] [blame]	3780	<p>The '<tt>bitcast</tt>' instruction converts <tt>value</tt> to type
Reid Spencer	7267925	2006-11-11 21:00:47 +0000	[diff] [blame]	3781	<tt>ty2</tt>. It is always a <i>no-op cast</i> because no bits change with
				3782	this conversion. The conversion is done as if the <tt>value</tt> had been
				3783	stored to memory and read back as type <tt>ty2</tt>. Pointer types may only be
				3784	converted to other pointer types with this instruction. To convert pointers to
				3785	other types, use the <a href="#i_inttoptr">inttoptr</a> or
				3786	<a href="#i_ptrtoint">ptrtoint</a> instructions first.</p>
Reid Spencer	9dee3ac	2006-11-08 01:11:31 +0000	[diff] [blame]	3787
				3788	<h5>Example:</h5>
				3789	<pre>
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	3790	%X = bitcast i8 255 to i8 <i>; yields i8 :-1</i>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3791	%Y = bitcast i32* %x to sint* <i>; yields sint*:%x</i>
				3792	%Z = bitcast <2xint> %V to i64; <i>; yields i64: %V</i>
Chris Lattner	33ba0d9	2001-07-09 00:26:23 +0000	[diff] [blame]	3793	</pre>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	3794	</div>
Chris Lattner	cc37aae	2004-03-12 05:50:16 +0000	[diff] [blame]	3795
Reid Spencer	2fd21e6	2006-11-08 01:18:52 +0000	[diff] [blame]	3796	<!-- ======================================================================= -->
				3797	<div class="doc_subsection"> <a name="otherops">Other Operations</a> </div>
				3798	<div class="doc_text">
				3799	<p>The instructions in this category are the "miscellaneous"
				3800	instructions, which defy better classification.</p>
				3801	</div>
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3802
				3803	<!-- _______________________________________________________________________ -->
				3804	<div class="doc_subsubsection"><a name="i_icmp">'<tt>icmp</tt>' Instruction</a>
				3805	</div>
				3806	<div class="doc_text">
				3807	<h5>Syntax:</h5>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3808	<pre> <result> = icmp <cond> <ty> <op1>, <op2> <i>; yields {i1}:result</i>
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3809	</pre>
				3810	<h5>Overview:</h5>
				3811	<p>The '<tt>icmp</tt>' instruction returns a boolean value based on comparison
Chris Lattner	4316dec	2008-04-02 00:38:26 +0000	[diff] [blame]	3812	of its two integer or pointer operands.</p>
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3813	<h5>Arguments:</h5>
				3814	<p>The '<tt>icmp</tt>' instruction takes three operands. The first operand is
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	3815	the condition code indicating the kind of comparison to perform. It is not
				3816	a value, just a keyword. The possible condition code are:
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3817	<ol>
				3818	<li><tt>eq</tt>: equal</li>
				3819	<li><tt>ne</tt>: not equal </li>
				3820	<li><tt>ugt</tt>: unsigned greater than</li>
				3821	<li><tt>uge</tt>: unsigned greater or equal</li>
				3822	<li><tt>ult</tt>: unsigned less than</li>
				3823	<li><tt>ule</tt>: unsigned less or equal</li>
				3824	<li><tt>sgt</tt>: signed greater than</li>
				3825	<li><tt>sge</tt>: signed greater or equal</li>
				3826	<li><tt>slt</tt>: signed less than</li>
				3827	<li><tt>sle</tt>: signed less or equal</li>
				3828	</ol>
Chris Lattner	3b19d65	2007-01-15 01:54:13 +0000	[diff] [blame]	3829	<p>The remaining two arguments must be <a href="#t_integer">integer</a> or
Reid Spencer	350f8aa	2007-01-04 05:19:58 +0000	[diff] [blame]	3830	<a href="#t_pointer">pointer</a> typed. They must also be identical types.</p>
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3831	<h5>Semantics:</h5>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3832	<p>The '<tt>icmp</tt>' compares <tt>op1</tt> and <tt>op2</tt> according to
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3833	the condition code given as <tt>cond</tt>. The comparison performed always
Reid Spencer	c78f337	2007-01-12 03:35:51 +0000	[diff] [blame]	3834	yields a <a href="#t_primitive">i1</a> result, as follows:
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3835	<ol>
				3836	<li><tt>eq</tt>: yields <tt>true</tt> if the operands are equal,
				3837	<tt>false</tt> otherwise. No sign interpretation is necessary or performed.
				3838	</li>
				3839	<li><tt>ne</tt>: yields <tt>true</tt> if the operands are unequal,
				3840	<tt>false</tt> otherwise. No sign interpretation is necessary or performed.
				3841	<li><tt>ugt</tt>: interprets the operands as unsigned values and yields
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3842	<tt>true</tt> if <tt>op1</tt> is greater than <tt>op2</tt>.</li>
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3843	<li><tt>uge</tt>: interprets the operands as unsigned values and yields
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3844	<tt>true</tt> if <tt>op1</tt> is greater than or equal to <tt>op2</tt>.</li>
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3845	<li><tt>ult</tt>: interprets the operands as unsigned values and yields
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3846	<tt>true</tt> if <tt>op1</tt> is less than <tt>op2</tt>.</li>
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3847	<li><tt>ule</tt>: interprets the operands as unsigned values and yields
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3848	<tt>true</tt> if <tt>op1</tt> is less than or equal to <tt>op2</tt>.</li>
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3849	<li><tt>sgt</tt>: interprets the operands as signed values and yields
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3850	<tt>true</tt> if <tt>op1</tt> is greater than <tt>op2</tt>.</li>
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3851	<li><tt>sge</tt>: interprets the operands as signed values and yields
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3852	<tt>true</tt> if <tt>op1</tt> is greater than or equal to <tt>op2</tt>.</li>
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3853	<li><tt>slt</tt>: interprets the operands as signed values and yields
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3854	<tt>true</tt> if <tt>op1</tt> is less than <tt>op2</tt>.</li>
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3855	<li><tt>sle</tt>: interprets the operands as signed values and yields
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3856	<tt>true</tt> if <tt>op1</tt> is less than or equal to <tt>op2</tt>.</li>
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3857	</ol>
				3858	<p>If the operands are <a href="#t_pointer">pointer</a> typed, the pointer
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	3859	values are compared as if they were integers.</p>
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3860
				3861	<h5>Example:</h5>
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	3862	<pre> <result> = icmp eq i32 4, 5 <i>; yields: result=false</i>
				3863	<result> = icmp ne float* %X, %X <i>; yields: result=false</i>
				3864	<result> = icmp ult i16 4, 5 <i>; yields: result=true</i>
				3865	<result> = icmp sgt i16 4, 5 <i>; yields: result=false</i>
				3866	<result> = icmp ule i16 -4, 5 <i>; yields: result=false</i>
				3867	<result> = icmp sge i16 4, 5 <i>; yields: result=false</i>
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3868	</pre>
				3869	</div>
				3870
				3871	<!-- _______________________________________________________________________ -->
				3872	<div class="doc_subsubsection"><a name="i_fcmp">'<tt>fcmp</tt>' Instruction</a>
				3873	</div>
				3874	<div class="doc_text">
				3875	<h5>Syntax:</h5>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3876	<pre> <result> = fcmp <cond> <ty> <op1>, <op2> <i>; yields {i1}:result</i>
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3877	</pre>
				3878	<h5>Overview:</h5>
				3879	<p>The '<tt>fcmp</tt>' instruction returns a boolean value based on comparison
				3880	of its floating point operands.</p>
				3881	<h5>Arguments:</h5>
				3882	<p>The '<tt>fcmp</tt>' instruction takes three operands. The first operand is
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	3883	the condition code indicating the kind of comparison to perform. It is not
				3884	a value, just a keyword. The possible condition code are:
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3885	<ol>
Reid Spencer	b7f2628	2006-11-19 03:00:14 +0000	[diff] [blame]	3886	<li><tt>false</tt>: no comparison, always returns false</li>
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3887	<li><tt>oeq</tt>: ordered and equal</li>
				3888	<li><tt>ogt</tt>: ordered and greater than </li>
				3889	<li><tt>oge</tt>: ordered and greater than or equal</li>
				3890	<li><tt>olt</tt>: ordered and less than </li>
				3891	<li><tt>ole</tt>: ordered and less than or equal</li>
				3892	<li><tt>one</tt>: ordered and not equal</li>
				3893	<li><tt>ord</tt>: ordered (no nans)</li>
				3894	<li><tt>ueq</tt>: unordered or equal</li>
				3895	<li><tt>ugt</tt>: unordered or greater than </li>
				3896	<li><tt>uge</tt>: unordered or greater than or equal</li>
				3897	<li><tt>ult</tt>: unordered or less than </li>
				3898	<li><tt>ule</tt>: unordered or less than or equal</li>
				3899	<li><tt>une</tt>: unordered or not equal</li>
				3900	<li><tt>uno</tt>: unordered (either nans)</li>
Reid Spencer	b7f2628	2006-11-19 03:00:14 +0000	[diff] [blame]	3901	<li><tt>true</tt>: no comparison, always returns true</li>
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3902	</ol>
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	3903	<p><i>Ordered</i> means that neither operand is a QNAN while
Reid Spencer	93a4985	2006-12-06 07:08:07 +0000	[diff] [blame]	3904	<i>unordered</i> means that either operand may be a QNAN.</p>
Reid Spencer	350f8aa	2007-01-04 05:19:58 +0000	[diff] [blame]	3905	<p>The <tt>val1</tt> and <tt>val2</tt> arguments must be
				3906	<a href="#t_floating">floating point</a> typed. They must have identical
				3907	types.</p>
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3908	<h5>Semantics:</h5>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3909	<p>The '<tt>fcmp</tt>' instruction compares <tt>op1</tt> and <tt>op2</tt>
Nate Begeman	ac80ade	2008-05-12 19:01:56 +0000	[diff] [blame]	3910	according to the condition code given as <tt>cond</tt>. The comparison performed
				3911	always yields a <a href="#t_primitive">i1</a> result, as follows:
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3912	<ol>
				3913	<li><tt>false</tt>: always yields <tt>false</tt>, regardless of operands.</li>
Reid Spencer	b7f2628	2006-11-19 03:00:14 +0000	[diff] [blame]	3914	<li><tt>oeq</tt>: yields <tt>true</tt> if both operands are not a QNAN and
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3915	<tt>op1</tt> is equal to <tt>op2</tt>.</li>
Reid Spencer	b7f2628	2006-11-19 03:00:14 +0000	[diff] [blame]	3916	<li><tt>ogt</tt>: yields <tt>true</tt> if both operands are not a QNAN and
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3917	<tt>op1</tt> is greather than <tt>op2</tt>.</li>
Reid Spencer	b7f2628	2006-11-19 03:00:14 +0000	[diff] [blame]	3918	<li><tt>oge</tt>: yields <tt>true</tt> if both operands are not a QNAN and
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3919	<tt>op1</tt> is greater than or equal to <tt>op2</tt>.</li>
Reid Spencer	b7f2628	2006-11-19 03:00:14 +0000	[diff] [blame]	3920	<li><tt>olt</tt>: yields <tt>true</tt> if both operands are not a QNAN and
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3921	<tt>op1</tt> is less than <tt>op2</tt>.</li>
Reid Spencer	b7f2628	2006-11-19 03:00:14 +0000	[diff] [blame]	3922	<li><tt>ole</tt>: yields <tt>true</tt> if both operands are not a QNAN and
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3923	<tt>op1</tt> is less than or equal to <tt>op2</tt>.</li>
Reid Spencer	b7f2628	2006-11-19 03:00:14 +0000	[diff] [blame]	3924	<li><tt>one</tt>: yields <tt>true</tt> if both operands are not a QNAN and
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3925	<tt>op1</tt> is not equal to <tt>op2</tt>.</li>
Reid Spencer	b7f2628	2006-11-19 03:00:14 +0000	[diff] [blame]	3926	<li><tt>ord</tt>: yields <tt>true</tt> if both operands are not a QNAN.</li>
				3927	<li><tt>ueq</tt>: yields <tt>true</tt> if either operand is a QNAN or
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3928	<tt>op1</tt> is equal to <tt>op2</tt>.</li>
Reid Spencer	b7f2628	2006-11-19 03:00:14 +0000	[diff] [blame]	3929	<li><tt>ugt</tt>: yields <tt>true</tt> if either operand is a QNAN or
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3930	<tt>op1</tt> is greater than <tt>op2</tt>.</li>
Reid Spencer	b7f2628	2006-11-19 03:00:14 +0000	[diff] [blame]	3931	<li><tt>uge</tt>: yields <tt>true</tt> if either operand is a QNAN or
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3932	<tt>op1</tt> is greater than or equal to <tt>op2</tt>.</li>
Reid Spencer	b7f2628	2006-11-19 03:00:14 +0000	[diff] [blame]	3933	<li><tt>ult</tt>: yields <tt>true</tt> if either operand is a QNAN or
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3934	<tt>op1</tt> is less than <tt>op2</tt>.</li>
Reid Spencer	b7f2628	2006-11-19 03:00:14 +0000	[diff] [blame]	3935	<li><tt>ule</tt>: yields <tt>true</tt> if either operand is a QNAN or
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3936	<tt>op1</tt> is less than or equal to <tt>op2</tt>.</li>
Reid Spencer	b7f2628	2006-11-19 03:00:14 +0000	[diff] [blame]	3937	<li><tt>une</tt>: yields <tt>true</tt> if either operand is a QNAN or
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3938	<tt>op1</tt> is not equal to <tt>op2</tt>.</li>
Reid Spencer	b7f2628	2006-11-19 03:00:14 +0000	[diff] [blame]	3939	<li><tt>uno</tt>: yields <tt>true</tt> if either operand is a QNAN.</li>
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3940	<li><tt>true</tt>: always yields <tt>true</tt>, regardless of operands.</li>
				3941	</ol>
Reid Spencer	f3a70a6	2006-11-18 21:50:54 +0000	[diff] [blame]	3942
				3943	<h5>Example:</h5>
				3944	<pre> <result> = fcmp oeq float 4.0, 5.0 <i>; yields: result=false</i>
				3945	<result> = icmp one float 4.0, 5.0 <i>; yields: result=true</i>
				3946	<result> = icmp olt float 4.0, 5.0 <i>; yields: result=true</i>
				3947	<result> = icmp ueq double 1.0, 2.0 <i>; yields: result=false</i>
				3948	</pre>
				3949	</div>
				3950
Reid Spencer	2fd21e6	2006-11-08 01:18:52 +0000	[diff] [blame]	3951	<!-- _______________________________________________________________________ -->
Nate Begeman	ac80ade	2008-05-12 19:01:56 +0000	[diff] [blame]	3952	<div class="doc_subsubsection">
				3953	<a name="i_vicmp">'<tt>vicmp</tt>' Instruction</a>
				3954	</div>
				3955	<div class="doc_text">
				3956	<h5>Syntax:</h5>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3957	<pre> <result> = vicmp <cond> <ty> <op1>, <op2> <i>; yields {ty}:result</i>
Nate Begeman	ac80ade	2008-05-12 19:01:56 +0000	[diff] [blame]	3958	</pre>
				3959	<h5>Overview:</h5>
				3960	<p>The '<tt>vicmp</tt>' instruction returns an integer vector value based on
				3961	element-wise comparison of its two integer vector operands.</p>
				3962	<h5>Arguments:</h5>
				3963	<p>The '<tt>vicmp</tt>' instruction takes three operands. The first operand is
				3964	the condition code indicating the kind of comparison to perform. It is not
				3965	a value, just a keyword. The possible condition code are:
				3966	<ol>
				3967	<li><tt>eq</tt>: equal</li>
				3968	<li><tt>ne</tt>: not equal </li>
				3969	<li><tt>ugt</tt>: unsigned greater than</li>
				3970	<li><tt>uge</tt>: unsigned greater or equal</li>
				3971	<li><tt>ult</tt>: unsigned less than</li>
				3972	<li><tt>ule</tt>: unsigned less or equal</li>
				3973	<li><tt>sgt</tt>: signed greater than</li>
				3974	<li><tt>sge</tt>: signed greater or equal</li>
				3975	<li><tt>slt</tt>: signed less than</li>
				3976	<li><tt>sle</tt>: signed less or equal</li>
				3977	</ol>
				3978	<p>The remaining two arguments must be <a href="#t_vector">vector</a> of
				3979	<a href="#t_integer">integer</a> typed. They must also be identical types.</p>
				3980	<h5>Semantics:</h5>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	3981	<p>The '<tt>vicmp</tt>' instruction compares <tt>op1</tt> and <tt>op2</tt>
Nate Begeman	ac80ade	2008-05-12 19:01:56 +0000	[diff] [blame]	3982	according to the condition code given as <tt>cond</tt>. The comparison yields a
				3983	<a href="#t_vector">vector</a> of <a href="#t_integer">integer</a> result, of
				3984	identical type as the values being compared. The most significant bit in each
				3985	element is 1 if the element-wise comparison evaluates to true, and is 0
				3986	otherwise. All other bits of the result are undefined. The condition codes
				3987	are evaluated identically to the <a href="#i_icmp">'<tt>icmp</tt>'
				3988	instruction</a>.
				3989
				3990	<h5>Example:</h5>
				3991	<pre>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	3992	<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>
				3993	<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	ac80ade	2008-05-12 19:01:56 +0000	[diff] [blame]	3994	</pre>
				3995	</div>
				3996
				3997	<!-- _______________________________________________________________________ -->
				3998	<div class="doc_subsubsection">
				3999	<a name="i_vfcmp">'<tt>vfcmp</tt>' Instruction</a>
				4000	</div>
				4001	<div class="doc_text">
				4002	<h5>Syntax:</h5>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	4003	<pre> <result> = vfcmp <cond> <ty> <op1>, <op2></pre>
Nate Begeman	ac80ade	2008-05-12 19:01:56 +0000	[diff] [blame]	4004	<h5>Overview:</h5>
				4005	<p>The '<tt>vfcmp</tt>' instruction returns an integer vector value based on
				4006	element-wise comparison of its two floating point vector operands. The output
				4007	elements have the same width as the input elements.</p>
				4008	<h5>Arguments:</h5>
				4009	<p>The '<tt>vfcmp</tt>' instruction takes three operands. The first operand is
				4010	the condition code indicating the kind of comparison to perform. It is not
				4011	a value, just a keyword. The possible condition code are:
				4012	<ol>
				4013	<li><tt>false</tt>: no comparison, always returns false</li>
				4014	<li><tt>oeq</tt>: ordered and equal</li>
				4015	<li><tt>ogt</tt>: ordered and greater than </li>
				4016	<li><tt>oge</tt>: ordered and greater than or equal</li>
				4017	<li><tt>olt</tt>: ordered and less than </li>
				4018	<li><tt>ole</tt>: ordered and less than or equal</li>
				4019	<li><tt>one</tt>: ordered and not equal</li>
				4020	<li><tt>ord</tt>: ordered (no nans)</li>
				4021	<li><tt>ueq</tt>: unordered or equal</li>
				4022	<li><tt>ugt</tt>: unordered or greater than </li>
				4023	<li><tt>uge</tt>: unordered or greater than or equal</li>
				4024	<li><tt>ult</tt>: unordered or less than </li>
				4025	<li><tt>ule</tt>: unordered or less than or equal</li>
				4026	<li><tt>une</tt>: unordered or not equal</li>
				4027	<li><tt>uno</tt>: unordered (either nans)</li>
				4028	<li><tt>true</tt>: no comparison, always returns true</li>
				4029	</ol>
				4030	<p>The remaining two arguments must be <a href="#t_vector">vector</a> of
				4031	<a href="#t_floating">floating point</a> typed. They must also be identical
				4032	types.</p>
				4033	<h5>Semantics:</h5>
Gabor Greif	fb224a2	2008-08-07 21:46:00 +0000	[diff] [blame^]	4034	<p>The '<tt>vfcmp</tt>' instruction compares <tt>op1</tt> and <tt>op2</tt>
Nate Begeman	ac80ade	2008-05-12 19:01:56 +0000	[diff] [blame]	4035	according to the condition code given as <tt>cond</tt>. The comparison yields a
				4036	<a href="#t_vector">vector</a> of <a href="#t_integer">integer</a> result, with
				4037	an identical number of elements as the values being compared, and each element
				4038	having identical with to the width of the floating point elements. The most
				4039	significant bit in each element is 1 if the element-wise comparison evaluates to
				4040	true, and is 0 otherwise. All other bits of the result are undefined. The
				4041	condition codes are evaluated identically to the
				4042	<a href="#i_fcmp">'<tt>fcmp</tt>' instruction</a>.
				4043
				4044	<h5>Example:</h5>
				4045	<pre>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	4046	<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>
				4047	<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	ac80ade	2008-05-12 19:01:56 +0000	[diff] [blame]	4048	</pre>
				4049	</div>
				4050
				4051	<!-- _______________________________________________________________________ -->
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	4052	<div class="doc_subsubsection">
				4053	<a name="i_phi">'<tt>phi</tt>' Instruction</a>
				4054	</div>
				4055
Reid Spencer	2fd21e6	2006-11-08 01:18:52 +0000	[diff] [blame]	4056	<div class="doc_text">
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	4057
Reid Spencer	2fd21e6	2006-11-08 01:18:52 +0000	[diff] [blame]	4058	<h5>Syntax:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	4059
Reid Spencer	2fd21e6	2006-11-08 01:18:52 +0000	[diff] [blame]	4060	<pre> <result> = phi <ty> [ <val0>, <label0>], ...<br></pre>
				4061	<h5>Overview:</h5>
				4062	<p>The '<tt>phi</tt>' instruction is used to implement the φ node in
				4063	the SSA graph representing the function.</p>
				4064	<h5>Arguments:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	4065
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	4066	<p>The type of the incoming values is specified with the first type
Reid Spencer	2fd21e6	2006-11-08 01:18:52 +0000	[diff] [blame]	4067	field. After this, the '<tt>phi</tt>' instruction takes a list of pairs
				4068	as arguments, with one pair for each predecessor basic block of the
				4069	current block. Only values of <a href="#t_firstclass">first class</a>
				4070	type may be used as the value arguments to the PHI node. Only labels
				4071	may be used as the label arguments.</p>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	4072
Reid Spencer	2fd21e6	2006-11-08 01:18:52 +0000	[diff] [blame]	4073	<p>There must be no non-phi instructions between the start of a basic
				4074	block and the PHI instructions: i.e. PHI instructions must be first in
				4075	a basic block.</p>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	4076
Reid Spencer	2fd21e6	2006-11-08 01:18:52 +0000	[diff] [blame]	4077	<h5>Semantics:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	4078
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	4079	<p>At runtime, the '<tt>phi</tt>' instruction logically takes on the value
				4080	specified by the pair corresponding to the predecessor basic block that executed
				4081	just prior to the current block.</p>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	4082
Reid Spencer	2fd21e6	2006-11-08 01:18:52 +0000	[diff] [blame]	4083	<h5>Example:</h5>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	4084	<pre>
				4085	Loop: ; Infinite loop that counts from 0 on up...
				4086	%indvar = phi i32 [ 0, %LoopHeader ], [ %nextindvar, %Loop ]
				4087	%nextindvar = add i32 %indvar, 1
				4088	br label %Loop
				4089	</pre>
Reid Spencer	2fd21e6	2006-11-08 01:18:52 +0000	[diff] [blame]	4090	</div>
				4091
Chris Lattner	cc37aae	2004-03-12 05:50:16 +0000	[diff] [blame]	4092	<!-- _______________________________________________________________________ -->
				4093	<div class="doc_subsubsection">
				4094	<a name="i_select">'<tt>select</tt>' Instruction</a>
				4095	</div>
				4096
				4097	<div class="doc_text">
				4098
				4099	<h5>Syntax:</h5>
				4100
				4101	<pre>
Reid Spencer	c78f337	2007-01-12 03:35:51 +0000	[diff] [blame]	4102	<result> = select i1 <cond>, <ty> <val1>, <ty> <val2> <i>; yields ty</i>
Chris Lattner	cc37aae	2004-03-12 05:50:16 +0000	[diff] [blame]	4103	</pre>
				4104
				4105	<h5>Overview:</h5>
				4106
				4107	<p>
				4108	The '<tt>select</tt>' instruction is used to choose one value based on a
				4109	condition, without branching.
				4110	</p>
				4111
				4112
				4113	<h5>Arguments:</h5>
				4114
				4115	<p>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	4116	The '<tt>select</tt>' instruction requires an 'i1' value indicating the
				4117	condition, and two values of the same <a href="#t_firstclass">first class</a>
				4118	type. If the val1/val2 are vectors, the entire vectors are selected, not
				4119	individual elements.
Chris Lattner	cc37aae	2004-03-12 05:50:16 +0000	[diff] [blame]	4120	</p>
				4121
				4122	<h5>Semantics:</h5>
				4123
				4124	<p>
Chris Lattner	5568e94	2008-05-20 20:48:21 +0000	[diff] [blame]	4125	If the i1 condition evaluates is 1, the instruction returns the first
John Criswell	fc6b895	2005-05-16 16:17:45 +0000	[diff] [blame]	4126	value argument; otherwise, it returns the second value argument.
Chris Lattner	cc37aae	2004-03-12 05:50:16 +0000	[diff] [blame]	4127	</p>
				4128
				4129	<h5>Example:</h5>
				4130
				4131	<pre>
Reid Spencer	c78f337	2007-01-12 03:35:51 +0000	[diff] [blame]	4132	%X = select i1 true, i8 17, i8 42 <i>; yields i8:17</i>
Chris Lattner	cc37aae	2004-03-12 05:50:16 +0000	[diff] [blame]	4133	</pre>
				4134	</div>
				4135
Robert Bocchino	05ccd70	2006-01-15 20:48:27 +0000	[diff] [blame]	4136
				4137	<!-- _______________________________________________________________________ -->
				4138	<div class="doc_subsubsection">
Chris Lattner	2bff524	2005-05-06 05:47:36 +0000	[diff] [blame]	4139	<a name="i_call">'<tt>call</tt>' Instruction</a>
				4140	</div>
				4141
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	4142	<div class="doc_text">
Chris Lattner	2bff524	2005-05-06 05:47:36 +0000	[diff] [blame]	4143
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	4144	<h5>Syntax:</h5>
Chris Lattner	2bff524	2005-05-06 05:47:36 +0000	[diff] [blame]	4145	<pre>
Nick Lewycky	db7e3c9	2007-09-08 13:57:50 +0000	[diff] [blame]	4146	<result> = [tail] call [<a href="#callingconv">cconv</a>] <ty> [<fnty>*] <fnptrval>(<param list>)
Chris Lattner	2bff524	2005-05-06 05:47:36 +0000	[diff] [blame]	4147	</pre>
				4148
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	4149	<h5>Overview:</h5>
Chris Lattner	2bff524	2005-05-06 05:47:36 +0000	[diff] [blame]	4150
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	4151	<p>The '<tt>call</tt>' instruction represents a simple function call.</p>
Chris Lattner	2bff524	2005-05-06 05:47:36 +0000	[diff] [blame]	4152
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	4153	<h5>Arguments:</h5>
Chris Lattner	2bff524	2005-05-06 05:47:36 +0000	[diff] [blame]	4154
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	4155	<p>This instruction requires several arguments:</p>
Chris Lattner	2bff524	2005-05-06 05:47:36 +0000	[diff] [blame]	4156
Chris Lattner	6536cfe	2002-05-06 22:08:29 +0000	[diff] [blame]	4157	<ol>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	4158	<li>
Chris Lattner	bad10ee	2005-05-06 22:57:40 +0000	[diff] [blame]	4159	<p>The optional "tail" marker indicates whether the callee function accesses
				4160	any allocas or varargs in the caller. If the "tail" marker is present, the
Chris Lattner	2bff524	2005-05-06 05:47:36 +0000	[diff] [blame]	4161	function call is eligible for tail call optimization. Note that calls may
				4162	be marked "tail" even if they do not occur before a <a
				4163	href="#i_ret"><tt>ret</tt></a> instruction.
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	4164	</li>
				4165	<li>
Duncan Sands	8036ca4	2007-03-30 12:22:09 +0000	[diff] [blame]	4166	<p>The optional "cconv" marker indicates which <a href="#callingconv">calling
Chris Lattner	bad10ee	2005-05-06 22:57:40 +0000	[diff] [blame]	4167	convention</a> the call should use. If none is specified, the call defaults
				4168	to using C calling conventions.
				4169	</li>
				4170	<li>
Nick Lewycky	db7e3c9	2007-09-08 13:57:50 +0000	[diff] [blame]	4171	<p>'<tt>ty</tt>': the type of the call instruction itself which is also
				4172	the type of the return value. Functions that return no value are marked
				4173	<tt><a href="#t_void">void</a></tt>.</p>
				4174	</li>
				4175	<li>
				4176	<p>'<tt>fnty</tt>': shall be the signature of the pointer to function
				4177	value being invoked. The argument types must match the types implied by
				4178	this signature. This type can be omitted if the function is not varargs
				4179	and if the function type does not return a pointer to a function.</p>
Chris Lattner	2bff524	2005-05-06 05:47:36 +0000	[diff] [blame]	4180	</li>
				4181	<li>
				4182	<p>'<tt>fnptrval</tt>': An LLVM value containing a pointer to a function to
				4183	be invoked. In most cases, this is a direct function invocation, but
				4184	indirect <tt>call</tt>s are just as possible, calling an arbitrary pointer
John Criswell	fc6b895	2005-05-16 16:17:45 +0000	[diff] [blame]	4185	to function value.</p>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	4186	</li>
				4187	<li>
				4188	<p>'<tt>function args</tt>': argument list whose types match the
Reid Spencer	a7e302a	2005-05-01 22:22:57 +0000	[diff] [blame]	4189	function signature argument types. All arguments must be of
				4190	<a href="#t_firstclass">first class</a> type. If the function signature
				4191	indicates the function accepts a variable number of arguments, the extra
				4192	arguments can be specified.</p>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	4193	</li>
Chris Lattner	6536cfe	2002-05-06 22:08:29 +0000	[diff] [blame]	4194	</ol>
Chris Lattner	2bff524	2005-05-06 05:47:36 +0000	[diff] [blame]	4195
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	4196	<h5>Semantics:</h5>
Chris Lattner	2bff524	2005-05-06 05:47:36 +0000	[diff] [blame]	4197
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	4198	<p>The '<tt>call</tt>' instruction is used to cause control flow to
				4199	transfer to a specified function, with its incoming arguments bound to
				4200	the specified values. Upon a '<tt><a href="#i_ret">ret</a></tt>'
				4201	instruction in the called function, control flow continues with the
				4202	instruction after the function call, and the return value of the
Chris Lattner	772fccf	2008-03-21 17:24:17 +0000	[diff] [blame]	4203	function is bound to the result argument. If the callee returns multiple
				4204	values then the return values of the function are only accessible through
				4205	the '<tt><a href="#i_getresult">getresult</a></tt>' instruction.</p>
Chris Lattner	2bff524	2005-05-06 05:47:36 +0000	[diff] [blame]	4206
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	4207	<h5>Example:</h5>
Chris Lattner	2bff524	2005-05-06 05:47:36 +0000	[diff] [blame]	4208
				4209	<pre>
Nick Lewycky	db7e3c9	2007-09-08 13:57:50 +0000	[diff] [blame]	4210	%retval = call i32 @test(i32 %argc)
Chris Lattner	772fccf	2008-03-21 17:24:17 +0000	[diff] [blame]	4211	call i32 (i8 , ...) @printf(i8 * %msg, i32 12, i8 42) <i>; yields i32</i>
				4212	%X = tail call i32 @foo() <i>; yields i32</i>
				4213	%Y = tail call <a href="#callingconv">fastcc</a> i32 @foo() <i>; yields i32</i>
				4214	call void %foo(i8 97 signext)
Devang Patel	c3fc6df	2008-03-10 20:49:15 +0000	[diff] [blame]	4215
				4216	%struct.A = type { i32, i8 }
Chris Lattner	772fccf	2008-03-21 17:24:17 +0000	[diff] [blame]	4217	%r = call %struct.A @foo() <i>; yields { 32, i8 }</i>
				4218	%gr = getresult %struct.A %r, 0 <i>; yields i32</i>
				4219	%gr1 = getresult %struct.A %r, 1 <i>; yields i8</i>
Chris Lattner	2bff524	2005-05-06 05:47:36 +0000	[diff] [blame]	4220	</pre>
				4221
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	4222	</div>
Chris Lattner	e19d7a7	2004-09-27 21:51:25 +0000	[diff] [blame]	4223
Chris Lattner	d9ad5b3	2003-05-08 04:57:36 +0000	[diff] [blame]	4224	<!-- _______________________________________________________________________ -->
Chris Lattner	e19d7a7	2004-09-27 21:51:25 +0000	[diff] [blame]	4225	<div class="doc_subsubsection">
Chris Lattner	fb6977d	2006-01-13 23:26:01 +0000	[diff] [blame]	4226	<a name="i_va_arg">'<tt>va_arg</tt>' Instruction</a>
Chris Lattner	e19d7a7	2004-09-27 21:51:25 +0000	[diff] [blame]	4227	</div>
				4228
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	4229	<div class="doc_text">
Chris Lattner	e19d7a7	2004-09-27 21:51:25 +0000	[diff] [blame]	4230
Chris Lattner	8d1a81d	2003-10-18 05:51:36 +0000	[diff] [blame]	4231	<h5>Syntax:</h5>
Chris Lattner	e19d7a7	2004-09-27 21:51:25 +0000	[diff] [blame]	4232
				4233	<pre>
Andrew Lenharth	8bf607a	2005-06-18 18:28:17 +0000	[diff] [blame]	4234	<resultval> = va_arg <va_list*> <arglist>, <argty>
Chris Lattner	e19d7a7	2004-09-27 21:51:25 +0000	[diff] [blame]	4235	</pre>
				4236
Chris Lattner	8d1a81d	2003-10-18 05:51:36 +0000	[diff] [blame]	4237	<h5>Overview:</h5>
Chris Lattner	e19d7a7	2004-09-27 21:51:25 +0000	[diff] [blame]	4238
Andrew Lenharth	8bf607a	2005-06-18 18:28:17 +0000	[diff] [blame]	4239	<p>The '<tt>va_arg</tt>' instruction is used to access arguments passed through
Chris Lattner	e19d7a7	2004-09-27 21:51:25 +0000	[diff] [blame]	4240	the "variable argument" area of a function call. It is used to implement the
				4241	<tt>va_arg</tt> macro in C.</p>
				4242
Chris Lattner	8d1a81d	2003-10-18 05:51:36 +0000	[diff] [blame]	4243	<h5>Arguments:</h5>
Chris Lattner	e19d7a7	2004-09-27 21:51:25 +0000	[diff] [blame]	4244
Andrew Lenharth	8bf607a	2005-06-18 18:28:17 +0000	[diff] [blame]	4245	<p>This instruction takes a <tt>va_list*</tt> value and the type of
				4246	the argument. It returns a value of the specified argument type and
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	4247	increments the <tt>va_list</tt> to point to the next argument. The
Andrew Lenharth	8bf607a	2005-06-18 18:28:17 +0000	[diff] [blame]	4248	actual type of <tt>va_list</tt> is target specific.</p>
Chris Lattner	e19d7a7	2004-09-27 21:51:25 +0000	[diff] [blame]	4249
Chris Lattner	8d1a81d	2003-10-18 05:51:36 +0000	[diff] [blame]	4250	<h5>Semantics:</h5>
Chris Lattner	e19d7a7	2004-09-27 21:51:25 +0000	[diff] [blame]	4251
Andrew Lenharth	8bf607a	2005-06-18 18:28:17 +0000	[diff] [blame]	4252	<p>The '<tt>va_arg</tt>' instruction loads an argument of the specified
				4253	type from the specified <tt>va_list</tt> and causes the
				4254	<tt>va_list</tt> to point to the next argument. For more information,
				4255	see the variable argument handling <a href="#int_varargs">Intrinsic
				4256	Functions</a>.</p>
Chris Lattner	e19d7a7	2004-09-27 21:51:25 +0000	[diff] [blame]	4257
				4258	<p>It is legal for this instruction to be called in a function which does not
				4259	take a variable number of arguments, for example, the <tt>vfprintf</tt>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	4260	function.</p>
Chris Lattner	e19d7a7	2004-09-27 21:51:25 +0000	[diff] [blame]	4261
Andrew Lenharth	8bf607a	2005-06-18 18:28:17 +0000	[diff] [blame]	4262	<p><tt>va_arg</tt> is an LLVM instruction instead of an <a
John Criswell	fc6b895	2005-05-16 16:17:45 +0000	[diff] [blame]	4263	href="#intrinsics">intrinsic function</a> because it takes a type as an
Chris Lattner	e19d7a7	2004-09-27 21:51:25 +0000	[diff] [blame]	4264	argument.</p>
				4265
Chris Lattner	8d1a81d	2003-10-18 05:51:36 +0000	[diff] [blame]	4266	<h5>Example:</h5>
Chris Lattner	e19d7a7	2004-09-27 21:51:25 +0000	[diff] [blame]	4267
				4268	<p>See the <a href="#int_varargs">variable argument processing</a> section.</p>
				4269
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	4270	</div>
Chris Lattner	8ff7590	2004-01-06 05:31:32 +0000	[diff] [blame]	4271
Devang Patel	c3fc6df	2008-03-10 20:49:15 +0000	[diff] [blame]	4272	<!-- _______________________________________________________________________ -->
				4273	<div class="doc_subsubsection">
				4274	<a name="i_getresult">'<tt>getresult</tt>' Instruction</a>
				4275	</div>
				4276
				4277	<div class="doc_text">
				4278
				4279	<h5>Syntax:</h5>
				4280	<pre>
Chris Lattner	45c5e8b	2008-03-21 17:20:51 +0000	[diff] [blame]	4281	<resultval> = getresult <type> <retval>, <index>
Devang Patel	c3fc6df	2008-03-10 20:49:15 +0000	[diff] [blame]	4282	</pre>
Chris Lattner	45c5e8b	2008-03-21 17:20:51 +0000	[diff] [blame]	4283
Devang Patel	c3fc6df	2008-03-10 20:49:15 +0000	[diff] [blame]	4284	<h5>Overview:</h5>
				4285
				4286	<p> The '<tt>getresult</tt>' instruction is used to extract individual values
Chris Lattner	45c5e8b	2008-03-21 17:20:51 +0000	[diff] [blame]	4287	from a '<tt><a href="#i_call">call</a></tt>'
				4288	or '<tt><a href="#i_invoke">invoke</a></tt>' instruction that returns multiple
				4289	results.</p>
Devang Patel	c3fc6df	2008-03-10 20:49:15 +0000	[diff] [blame]	4290
				4291	<h5>Arguments:</h5>
				4292
Chris Lattner	45c5e8b	2008-03-21 17:20:51 +0000	[diff] [blame]	4293	<p>The '<tt>getresult</tt>' instruction takes a call or invoke value as its
Chris Lattner	1c406d7	2008-04-23 04:06:52 +0000	[diff] [blame]	4294	first argument, or an undef value. The value must have <a
				4295	href="#t_struct">structure type</a>. The second argument is a constant
				4296	unsigned index value which must be in range for the number of values returned
				4297	by the call.</p>
Devang Patel	c3fc6df	2008-03-10 20:49:15 +0000	[diff] [blame]	4298
				4299	<h5>Semantics:</h5>
				4300
Chris Lattner	45c5e8b	2008-03-21 17:20:51 +0000	[diff] [blame]	4301	<p>The '<tt>getresult</tt>' instruction extracts the element identified by
				4302	'<tt>index</tt>' from the aggregate value.</p>
Devang Patel	c3fc6df	2008-03-10 20:49:15 +0000	[diff] [blame]	4303
				4304	<h5>Example:</h5>
				4305
				4306	<pre>
				4307	%struct.A = type { i32, i8 }
				4308
				4309	%r = call %struct.A @foo()
Chris Lattner	45c5e8b	2008-03-21 17:20:51 +0000	[diff] [blame]	4310	%gr = getresult %struct.A %r, 0 <i>; yields i32:%gr</i>
				4311	%gr1 = getresult %struct.A %r, 1 <i>; yields i8:%gr1</i>
Devang Patel	c3fc6df	2008-03-10 20:49:15 +0000	[diff] [blame]	4312	add i32 %gr, 42
				4313	add i8 %gr1, 41
				4314	</pre>
				4315
				4316	</div>
				4317
Chris Lattner	d9ad5b3	2003-05-08 04:57:36 +0000	[diff] [blame]	4318	<!-- *********************************************************************** -->
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	4319	<div class="doc_section"> <a name="intrinsics">Intrinsic Functions</a> </div>
				4320	<!-- *********************************************************************** -->
Chris Lattner	8ff7590	2004-01-06 05:31:32 +0000	[diff] [blame]	4321
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	4322	<div class="doc_text">
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4323
				4324	<p>LLVM supports the notion of an "intrinsic function". These functions have
Reid Spencer	409e28f	2007-04-01 08:04:23 +0000	[diff] [blame]	4325	well known names and semantics and are required to follow certain restrictions.
				4326	Overall, these intrinsics represent an extension mechanism for the LLVM
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	4327	language that does not require changing all of the transformations in LLVM when
Gabor Greif	04367bf	2007-07-06 22:07:22 +0000	[diff] [blame]	4328	adding to the language (or the bitcode reader/writer, the parser, etc...).</p>
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4329
John Criswell	fc6b895	2005-05-16 16:17:45 +0000	[diff] [blame]	4330	<p>Intrinsic function names must all start with an "<tt>llvm.</tt>" prefix. This
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	4331	prefix is reserved in LLVM for intrinsic names; thus, function names may not
				4332	begin with this prefix. Intrinsic functions must always be external functions:
				4333	you cannot define the body of intrinsic functions. Intrinsic functions may
				4334	only be used in call or invoke instructions: it is illegal to take the address
				4335	of an intrinsic function. Additionally, because intrinsic functions are part
				4336	of the LLVM language, it is required if any are added that they be documented
				4337	here.</p>
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4338
Chandler Carruth	6994040	2007-08-04 01:51:18 +0000	[diff] [blame]	4339	<p>Some intrinsic functions can be overloaded, i.e., the intrinsic represents
				4340	a family of functions that perform the same operation but on different data
				4341	types. Because LLVM can represent over 8 million different integer types,
				4342	overloading is used commonly to allow an intrinsic function to operate on any
				4343	integer type. One or more of the argument types or the result type can be
				4344	overloaded to accept any integer type. Argument types may also be defined as
				4345	exactly matching a previous argument's type or the result type. This allows an
				4346	intrinsic function which accepts multiple arguments, but needs all of them to
				4347	be of the same type, to only be overloaded with respect to a single argument or
				4348	the result.</p>
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4349
Chandler Carruth	6994040	2007-08-04 01:51:18 +0000	[diff] [blame]	4350	<p>Overloaded intrinsics will have the names of its overloaded argument types
				4351	encoded into its function name, each preceded by a period. Only those types
				4352	which are overloaded result in a name suffix. Arguments whose type is matched
				4353	against another type do not. For example, the <tt>llvm.ctpop</tt> function can
				4354	take an integer of any width and returns an integer of exactly the same integer
				4355	width. This leads to a family of functions such as
				4356	<tt>i8 @llvm.ctpop.i8(i8 %val)</tt> and <tt>i29 @llvm.ctpop.i29(i29 %val)</tt>.
				4357	Only one type, the return type, is overloaded, and only one type suffix is
				4358	required. Because the argument's type is matched against the return type, it
				4359	does not require its own name suffix.</p>
Reid Spencer	409e28f	2007-04-01 08:04:23 +0000	[diff] [blame]	4360
				4361	<p>To learn how to add an intrinsic function, please see the
				4362	<a href="ExtendingLLVM.html">Extending LLVM Guide</a>.
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4363	</p>
				4364
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	4365	</div>
Chris Lattner	8ff7590	2004-01-06 05:31:32 +0000	[diff] [blame]	4366
Chris Lattner	d9ad5b3	2003-05-08 04:57:36 +0000	[diff] [blame]	4367	<!-- ======================================================================= -->
Chris Lattner	8ff7590	2004-01-06 05:31:32 +0000	[diff] [blame]	4368	<div class="doc_subsection">
				4369	<a name="int_varargs">Variable Argument Handling Intrinsics</a>
				4370	</div>
				4371
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	4372	<div class="doc_text">
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4373
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	4374	<p>Variable argument support is defined in LLVM with the <a
Chris Lattner	fb6977d	2006-01-13 23:26:01 +0000	[diff] [blame]	4375	href="#i_va_arg"><tt>va_arg</tt></a> instruction and these three
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	4376	intrinsic functions. These functions are related to the similarly
				4377	named macros defined in the <tt><stdarg.h></tt> header file.</p>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4378
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	4379	<p>All of these functions operate on arguments that use a
				4380	target-specific value type "<tt>va_list</tt>". The LLVM assembly
				4381	language reference manual does not define what this type is, so all
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	4382	transformations should be prepared to handle these functions regardless of
				4383	the type used.</p>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4384
Chris Lattner	374ab30	2006-05-15 17:26:46 +0000	[diff] [blame]	4385	<p>This example shows how the <a href="#i_va_arg"><tt>va_arg</tt></a>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	4386	instruction and the variable argument handling intrinsic functions are
				4387	used.</p>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4388
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	4389	<div class="doc_code">
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4390	<pre>
Anton Korobeynikov	5d522f3	2007-03-21 23:58:04 +0000	[diff] [blame]	4391	define i32 @test(i32 %X, ...) {
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4392	; Initialize variable argument processing
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	4393	%ap = alloca i8*
Chris Lattner	b75137d	2007-01-08 07:55:15 +0000	[diff] [blame]	4394	%ap2 = bitcast i8** %ap to i8*
Anton Korobeynikov	5d522f3	2007-03-21 23:58:04 +0000	[diff] [blame]	4395	call void @llvm.va_start(i8* %ap2)
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4396
				4397	; Read a single integer argument
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	4398	%tmp = va_arg i8** %ap, i32
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4399
				4400	; Demonstrate usage of llvm.va_copy and llvm.va_end
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	4401	%aq = alloca i8*
Chris Lattner	b75137d	2007-01-08 07:55:15 +0000	[diff] [blame]	4402	%aq2 = bitcast i8** %aq to i8*
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	4403	call void @llvm.va_copy(i8* %aq2, i8* %ap2)
Anton Korobeynikov	5d522f3	2007-03-21 23:58:04 +0000	[diff] [blame]	4404	call void @llvm.va_end(i8* %aq2)
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4405
				4406	; Stop processing of arguments.
Anton Korobeynikov	5d522f3	2007-03-21 23:58:04 +0000	[diff] [blame]	4407	call void @llvm.va_end(i8* %ap2)
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	4408	ret i32 %tmp
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4409	}
Anton Korobeynikov	5d522f3	2007-03-21 23:58:04 +0000	[diff] [blame]	4410
				4411	declare void @llvm.va_start(i8*)
				4412	declare void @llvm.va_copy(i8, i8)
				4413	declare void @llvm.va_end(i8*)
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4414	</pre>
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	4415	</div>
Chris Lattner	8ff7590	2004-01-06 05:31:32 +0000	[diff] [blame]	4416
Bill Wendling	2f7a8b0	2007-05-29 09:04:49 +0000	[diff] [blame]	4417	</div>
				4418
Chris Lattner	d9ad5b3	2003-05-08 04:57:36 +0000	[diff] [blame]	4419	<!-- _______________________________________________________________________ -->
Chris Lattner	8ff7590	2004-01-06 05:31:32 +0000	[diff] [blame]	4420	<div class="doc_subsubsection">
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	4421	<a name="int_va_start">'<tt>llvm.va_start</tt>' Intrinsic</a>
Chris Lattner	8ff7590	2004-01-06 05:31:32 +0000	[diff] [blame]	4422	</div>
				4423
				4424
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	4425	<div class="doc_text">
Chris Lattner	d9ad5b3	2003-05-08 04:57:36 +0000	[diff] [blame]	4426	<h5>Syntax:</h5>
Chris Lattner	b75137d	2007-01-08 07:55:15 +0000	[diff] [blame]	4427	<pre> declare void %llvm.va_start(i8* <arglist>)<br></pre>
Chris Lattner	d9ad5b3	2003-05-08 04:57:36 +0000	[diff] [blame]	4428	<h5>Overview:</h5>
Andrew Lenharth	8bf607a	2005-06-18 18:28:17 +0000	[diff] [blame]	4429	<P>The '<tt>llvm.va_start</tt>' intrinsic initializes
				4430	<tt>*<arglist></tt> for subsequent use by <tt><a
				4431	href="#i_va_arg">va_arg</a></tt>.</p>
				4432
				4433	<h5>Arguments:</h5>
				4434
				4435	<P>The argument is a pointer to a <tt>va_list</tt> element to initialize.</p>
				4436
Chris Lattner	d9ad5b3	2003-05-08 04:57:36 +0000	[diff] [blame]	4437	<h5>Semantics:</h5>
Andrew Lenharth	8bf607a	2005-06-18 18:28:17 +0000	[diff] [blame]	4438
				4439	<P>The '<tt>llvm.va_start</tt>' intrinsic works just like the <tt>va_start</tt>
				4440	macro available in C. In a target-dependent way, it initializes the
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	4441	<tt>va_list</tt> element to which the argument points, so that the next call to
Andrew Lenharth	8bf607a	2005-06-18 18:28:17 +0000	[diff] [blame]	4442	<tt>va_arg</tt> will produce the first variable argument passed to the function.
				4443	Unlike the C <tt>va_start</tt> macro, this intrinsic does not need to know the
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	4444	last argument of the function as the compiler can figure that out.</p>
Andrew Lenharth	8bf607a	2005-06-18 18:28:17 +0000	[diff] [blame]	4445
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	4446	</div>
Chris Lattner	8ff7590	2004-01-06 05:31:32 +0000	[diff] [blame]	4447
Chris Lattner	d9ad5b3	2003-05-08 04:57:36 +0000	[diff] [blame]	4448	<!-- _______________________________________________________________________ -->
Chris Lattner	8ff7590	2004-01-06 05:31:32 +0000	[diff] [blame]	4449	<div class="doc_subsubsection">
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	4450	<a name="int_va_end">'<tt>llvm.va_end</tt>' Intrinsic</a>
Chris Lattner	8ff7590	2004-01-06 05:31:32 +0000	[diff] [blame]	4451	</div>
				4452
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	4453	<div class="doc_text">
Chris Lattner	d9ad5b3	2003-05-08 04:57:36 +0000	[diff] [blame]	4454	<h5>Syntax:</h5>
Anton Korobeynikov	ec43a06	2007-03-22 00:02:17 +0000	[diff] [blame]	4455	<pre> declare void @llvm.va_end(i8* <arglist>)<br></pre>
Chris Lattner	d9ad5b3	2003-05-08 04:57:36 +0000	[diff] [blame]	4456	<h5>Overview:</h5>
Chris Lattner	b75137d	2007-01-08 07:55:15 +0000	[diff] [blame]	4457
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	4458	<p>The '<tt>llvm.va_end</tt>' intrinsic destroys <tt>*<arglist></tt>,
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	4459	which has been initialized previously with <tt><a href="#int_va_start">llvm.va_start</a></tt>
Chris Lattner	261efe9	2003-11-25 01:02:51 +0000	[diff] [blame]	4460	or <tt><a href="#i_va_copy">llvm.va_copy</a></tt>.</p>
Chris Lattner	b75137d	2007-01-08 07:55:15 +0000	[diff] [blame]	4461
Chris Lattner	d9ad5b3	2003-05-08 04:57:36 +0000	[diff] [blame]	4462	<h5>Arguments:</h5>
Chris Lattner	b75137d	2007-01-08 07:55:15 +0000	[diff] [blame]	4463
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	4464	<p>The argument is a pointer to a <tt>va_list</tt> to destroy.</p>
Chris Lattner	b75137d	2007-01-08 07:55:15 +0000	[diff] [blame]	4465
Chris Lattner	d9ad5b3	2003-05-08 04:57:36 +0000	[diff] [blame]	4466	<h5>Semantics:</h5>
Chris Lattner	b75137d	2007-01-08 07:55:15 +0000	[diff] [blame]	4467
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	4468	<p>The '<tt>llvm.va_end</tt>' intrinsic works just like the <tt>va_end</tt>
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	4469	macro available in C. In a target-dependent way, it destroys the
				4470	<tt>va_list</tt> element to which the argument points. Calls to <a
				4471	href="#int_va_start"><tt>llvm.va_start</tt></a> and <a href="#int_va_copy">
				4472	<tt>llvm.va_copy</tt></a> must be matched exactly with calls to
				4473	<tt>llvm.va_end</tt>.</p>
Chris Lattner	b75137d	2007-01-08 07:55:15 +0000	[diff] [blame]	4474
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	4475	</div>
Chris Lattner	8ff7590	2004-01-06 05:31:32 +0000	[diff] [blame]	4476
Chris Lattner	d9ad5b3	2003-05-08 04:57:36 +0000	[diff] [blame]	4477	<!-- _______________________________________________________________________ -->
Chris Lattner	8ff7590	2004-01-06 05:31:32 +0000	[diff] [blame]	4478	<div class="doc_subsubsection">
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	4479	<a name="int_va_copy">'<tt>llvm.va_copy</tt>' Intrinsic</a>
Chris Lattner	8ff7590	2004-01-06 05:31:32 +0000	[diff] [blame]	4480	</div>
				4481
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	4482	<div class="doc_text">
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4483
Chris Lattner	d9ad5b3	2003-05-08 04:57:36 +0000	[diff] [blame]	4484	<h5>Syntax:</h5>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4485
				4486	<pre>
Anton Korobeynikov	ec43a06	2007-03-22 00:02:17 +0000	[diff] [blame]	4487	declare void @llvm.va_copy(i8* <destarglist>, i8* <srcarglist>)
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4488	</pre>
				4489
Chris Lattner	d9ad5b3	2003-05-08 04:57:36 +0000	[diff] [blame]	4490	<h5>Overview:</h5>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4491
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	4492	<p>The '<tt>llvm.va_copy</tt>' intrinsic copies the current argument position
				4493	from the source argument list to the destination argument list.</p>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4494
Chris Lattner	d9ad5b3	2003-05-08 04:57:36 +0000	[diff] [blame]	4495	<h5>Arguments:</h5>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4496
Andrew Lenharth	8bf607a	2005-06-18 18:28:17 +0000	[diff] [blame]	4497	<p>The first argument is a pointer to a <tt>va_list</tt> element to initialize.
Andrew Lenharth	d0a4c62	2005-06-22 20:38:11 +0000	[diff] [blame]	4498	The second argument is a pointer to a <tt>va_list</tt> element to copy from.</p>
Andrew Lenharth	8bf607a	2005-06-18 18:28:17 +0000	[diff] [blame]	4499
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4500
Chris Lattner	d9ad5b3	2003-05-08 04:57:36 +0000	[diff] [blame]	4501	<h5>Semantics:</h5>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4502
Jeff Cohen	b627eab	2007-04-29 01:07:00 +0000	[diff] [blame]	4503	<p>The '<tt>llvm.va_copy</tt>' intrinsic works just like the <tt>va_copy</tt>
				4504	macro available in C. In a target-dependent way, it copies the source
				4505	<tt>va_list</tt> element into the destination <tt>va_list</tt> element. This
				4506	intrinsic is necessary because the <tt><a href="#int_va_start">
				4507	llvm.va_start</a></tt> intrinsic may be arbitrarily complex and require, for
				4508	example, memory allocation.</p>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4509
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	4510	</div>
Chris Lattner	8ff7590	2004-01-06 05:31:32 +0000	[diff] [blame]	4511
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4512	<!-- ======================================================================= -->
				4513	<div class="doc_subsection">
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4514	<a name="int_gc">Accurate Garbage Collection Intrinsics</a>
				4515	</div>
				4516
				4517	<div class="doc_text">
				4518
				4519	<p>
				4520	LLVM support for <a href="GarbageCollection.html">Accurate Garbage
Chris Lattner	d3eda89	2008-08-05 18:29:16 +0000	[diff] [blame]	4521	Collection</a> (GC) requires the implementation and generation of these
				4522	intrinsics.
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	4523	These intrinsics allow identification of <a href="#int_gcroot">GC roots on the
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4524	stack</a>, as well as garbage collector implementations that require <a
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	4525	href="#int_gcread">read</a> and <a href="#int_gcwrite">write</a> barriers.
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4526	Front-ends for type-safe garbage collected languages should generate these
				4527	intrinsics to make use of the LLVM garbage collectors. For more details, see <a
				4528	href="GarbageCollection.html">Accurate Garbage Collection with LLVM</a>.
				4529	</p>
Christopher Lamb	303dae9	2007-12-17 01:00:21 +0000	[diff] [blame]	4530
				4531	<p>The garbage collection intrinsics only operate on objects in the generic
				4532	address space (address space zero).</p>
				4533
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4534	</div>
				4535
				4536	<!-- _______________________________________________________________________ -->
				4537	<div class="doc_subsubsection">
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	4538	<a name="int_gcroot">'<tt>llvm.gcroot</tt>' Intrinsic</a>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4539	</div>
				4540
				4541	<div class="doc_text">
				4542
				4543	<h5>Syntax:</h5>
				4544
				4545	<pre>
Chris Lattner	1df4f75	2007-09-21 17:30:40 +0000	[diff] [blame]	4546	declare void @llvm.gcroot(i8** %ptrloc, i8* %metadata)
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4547	</pre>
				4548
				4549	<h5>Overview:</h5>
				4550
John Criswell	9e2485c	2004-12-10 15:51:16 +0000	[diff] [blame]	4551	<p>The '<tt>llvm.gcroot</tt>' intrinsic declares the existence of a GC root to
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4552	the code generator, and allows some metadata to be associated with it.</p>
				4553
				4554	<h5>Arguments:</h5>
				4555
				4556	<p>The first argument specifies the address of a stack object that contains the
				4557	root pointer. The second pointer (which must be either a constant or a global
				4558	value address) contains the meta-data to be associated with the root.</p>
				4559
				4560	<h5>Semantics:</h5>
				4561
Chris Lattner	05d6709	2008-04-24 05:59:56 +0000	[diff] [blame]	4562	<p>At runtime, a call to this intrinsic stores a null pointer into the "ptrloc"
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4563	location. At compile-time, the code generator generates information to allow
Gordon Henriksen	e1433f2	2007-12-25 02:31:26 +0000	[diff] [blame]	4564	the runtime to find the pointer at GC safe points. The '<tt>llvm.gcroot</tt>'
				4565	intrinsic may only be used in a function which <a href="#gc">specifies a GC
				4566	algorithm</a>.</p>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4567
				4568	</div>
				4569
				4570
				4571	<!-- _______________________________________________________________________ -->
				4572	<div class="doc_subsubsection">
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	4573	<a name="int_gcread">'<tt>llvm.gcread</tt>' Intrinsic</a>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4574	</div>
				4575
				4576	<div class="doc_text">
				4577
				4578	<h5>Syntax:</h5>
				4579
				4580	<pre>
Chris Lattner	1df4f75	2007-09-21 17:30:40 +0000	[diff] [blame]	4581	declare i8* @llvm.gcread(i8* %ObjPtr, i8** %Ptr)
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4582	</pre>
				4583
				4584	<h5>Overview:</h5>
				4585
				4586	<p>The '<tt>llvm.gcread</tt>' intrinsic identifies reads of references from heap
				4587	locations, allowing garbage collector implementations that require read
				4588	barriers.</p>
				4589
				4590	<h5>Arguments:</h5>
				4591
Chris Lattner	80626e9	2006-03-14 20:02:51 +0000	[diff] [blame]	4592	<p>The second argument is the address to read from, which should be an address
				4593	allocated from the garbage collector. The first object is a pointer to the
				4594	start of the referenced object, if needed by the language runtime (otherwise
				4595	null).</p>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4596
				4597	<h5>Semantics:</h5>
				4598
				4599	<p>The '<tt>llvm.gcread</tt>' intrinsic has the same semantics as a load
				4600	instruction, but may be replaced with substantially more complex code by the
Gordon Henriksen	e1433f2	2007-12-25 02:31:26 +0000	[diff] [blame]	4601	garbage collector runtime, as needed. The '<tt>llvm.gcread</tt>' intrinsic
				4602	may only be used in a function which <a href="#gc">specifies a GC
				4603	algorithm</a>.</p>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4604
				4605	</div>
				4606
				4607
				4608	<!-- _______________________________________________________________________ -->
				4609	<div class="doc_subsubsection">
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	4610	<a name="int_gcwrite">'<tt>llvm.gcwrite</tt>' Intrinsic</a>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4611	</div>
				4612
				4613	<div class="doc_text">
				4614
				4615	<h5>Syntax:</h5>
				4616
				4617	<pre>
Chris Lattner	1df4f75	2007-09-21 17:30:40 +0000	[diff] [blame]	4618	declare void @llvm.gcwrite(i8* %P1, i8* %Obj, i8** %P2)
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4619	</pre>
				4620
				4621	<h5>Overview:</h5>
				4622
				4623	<p>The '<tt>llvm.gcwrite</tt>' intrinsic identifies writes of references to heap
				4624	locations, allowing garbage collector implementations that require write
				4625	barriers (such as generational or reference counting collectors).</p>
				4626
				4627	<h5>Arguments:</h5>
				4628
Chris Lattner	80626e9	2006-03-14 20:02:51 +0000	[diff] [blame]	4629	<p>The first argument is the reference to store, the second is the start of the
				4630	object to store it to, and the third is the address of the field of Obj to
				4631	store to. If the runtime does not require a pointer to the object, Obj may be
				4632	null.</p>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4633
				4634	<h5>Semantics:</h5>
				4635
				4636	<p>The '<tt>llvm.gcwrite</tt>' intrinsic has the same semantics as a store
				4637	instruction, but may be replaced with substantially more complex code by the
Gordon Henriksen	e1433f2	2007-12-25 02:31:26 +0000	[diff] [blame]	4638	garbage collector runtime, as needed. The '<tt>llvm.gcwrite</tt>' intrinsic
				4639	may only be used in a function which <a href="#gc">specifies a GC
				4640	algorithm</a>.</p>
Chris Lattner	d792391	2004-05-23 21:06:01 +0000	[diff] [blame]	4641
				4642	</div>
				4643
				4644
				4645
				4646	<!-- ======================================================================= -->
				4647	<div class="doc_subsection">
Chris Lattner	1061064	2004-02-14 04:08:35 +0000	[diff] [blame]	4648	<a name="int_codegen">Code Generator Intrinsics</a>
				4649	</div>
				4650
				4651	<div class="doc_text">
				4652	<p>
				4653	These intrinsics are provided by LLVM to expose special features that may only
				4654	be implemented with code generator support.
				4655	</p>
				4656
				4657	</div>
				4658
				4659	<!-- _______________________________________________________________________ -->
				4660	<div class="doc_subsubsection">
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	4661	<a name="int_returnaddress">'<tt>llvm.returnaddress</tt>' Intrinsic</a>
Chris Lattner	1061064	2004-02-14 04:08:35 +0000	[diff] [blame]	4662	</div>
				4663
				4664	<div class="doc_text">
				4665
				4666	<h5>Syntax:</h5>
				4667	<pre>
Anton Korobeynikov	ec43a06	2007-03-22 00:02:17 +0000	[diff] [blame]	4668	declare i8 *@llvm.returnaddress(i32 <level>)
Chris Lattner	1061064	2004-02-14 04:08:35 +0000	[diff] [blame]	4669	</pre>
				4670
				4671	<h5>Overview:</h5>
				4672
				4673	<p>
Chris Lattner	32b5d71	2006-10-15 20:05:59 +0000	[diff] [blame]	4674	The '<tt>llvm.returnaddress</tt>' intrinsic attempts to compute a
				4675	target-specific value indicating the return address of the current function
				4676	or one of its callers.
Chris Lattner	1061064	2004-02-14 04:08:35 +0000	[diff] [blame]	4677	</p>
				4678
				4679	<h5>Arguments:</h5>
				4680
				4681	<p>
				4682	The argument to this intrinsic indicates which function to return the address
				4683	for. Zero indicates the calling function, one indicates its caller, etc. The
				4684	argument is <b>required</b> to be a constant integer value.
				4685	</p>
				4686
				4687	<h5>Semantics:</h5>
				4688
				4689	<p>
				4690	The '<tt>llvm.returnaddress</tt>' intrinsic either returns a pointer indicating
				4691	the return address of the specified call frame, or zero if it cannot be
				4692	identified. The value returned by this intrinsic is likely to be incorrect or 0
				4693	for arguments other than zero, so it should only be used for debugging purposes.
				4694	</p>
				4695
				4696	<p>
				4697	Note that calling this intrinsic does not prevent function inlining or other
Chris Lattner	b40bb38	2005-03-07 20:30:51 +0000	[diff] [blame]	4698	aggressive transformations, so the value returned may not be that of the obvious
Chris Lattner	1061064	2004-02-14 04:08:35 +0000	[diff] [blame]	4699	source-language caller.
				4700	</p>
				4701	</div>
				4702
				4703
				4704	<!-- _______________________________________________________________________ -->
				4705	<div class="doc_subsubsection">
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	4706	<a name="int_frameaddress">'<tt>llvm.frameaddress</tt>' Intrinsic</a>
Chris Lattner	1061064	2004-02-14 04:08:35 +0000	[diff] [blame]	4707	</div>
				4708
				4709	<div class="doc_text">
				4710
				4711	<h5>Syntax:</h5>
				4712	<pre>
Chris Lattner	1df4f75	2007-09-21 17:30:40 +0000	[diff] [blame]	4713	declare i8 *@llvm.frameaddress(i32 <level>)
Chris Lattner	1061064	2004-02-14 04:08:35 +0000	[diff] [blame]	4714	</pre>
				4715
				4716	<h5>Overview:</h5>
				4717
				4718	<p>
Chris Lattner	32b5d71	2006-10-15 20:05:59 +0000	[diff] [blame]	4719	The '<tt>llvm.frameaddress</tt>' intrinsic attempts to return the
				4720	target-specific frame pointer value for the specified stack frame.
Chris Lattner	1061064	2004-02-14 04:08:35 +0000	[diff] [blame]	4721	</p>
				4722
				4723	<h5>Arguments:</h5>
				4724
				4725	<p>
				4726	The argument to this intrinsic indicates which function to return the frame
				4727	pointer for. Zero indicates the calling function, one indicates its caller,
				4728	etc. The argument is <b>required</b> to be a constant integer value.
				4729	</p>
				4730
				4731	<h5>Semantics:</h5>
				4732
				4733	<p>
				4734	The '<tt>llvm.frameaddress</tt>' intrinsic either returns a pointer indicating
				4735	the frame address of the specified call frame, or zero if it cannot be
				4736	identified. The value returned by this intrinsic is likely to be incorrect or 0
				4737	for arguments other than zero, so it should only be used for debugging purposes.
				4738	</p>
				4739
				4740	<p>
				4741	Note that calling this intrinsic does not prevent function inlining or other
Chris Lattner	b40bb38	2005-03-07 20:30:51 +0000	[diff] [blame]	4742	aggressive transformations, so the value returned may not be that of the obvious
Chris Lattner	1061064	2004-02-14 04:08:35 +0000	[diff] [blame]	4743	source-language caller.
				4744	</p>
				4745	</div>
				4746
Chris Lattner	9a9d7ac	2005-02-28 19:24:19 +0000	[diff] [blame]	4747	<!-- _______________________________________________________________________ -->
				4748	<div class="doc_subsubsection">
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	4749	<a name="int_stacksave">'<tt>llvm.stacksave</tt>' Intrinsic</a>
Chris Lattner	57e1f39	2006-01-13 02:03:13 +0000	[diff] [blame]	4750	</div>
				4751
				4752	<div class="doc_text">
				4753
				4754	<h5>Syntax:</h5>
				4755	<pre>
Chris Lattner	1df4f75	2007-09-21 17:30:40 +0000	[diff] [blame]	4756	declare i8 *@llvm.stacksave()
Chris Lattner	57e1f39	2006-01-13 02:03:13 +0000	[diff] [blame]	4757	</pre>
				4758
				4759	<h5>Overview:</h5>
				4760
				4761	<p>
				4762	The '<tt>llvm.stacksave</tt>' intrinsic is used to remember the current state of
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	4763	the function stack, for use with <a href="#int_stackrestore">
Chris Lattner	57e1f39	2006-01-13 02:03:13 +0000	[diff] [blame]	4764	<tt>llvm.stackrestore</tt></a>. This is useful for implementing language
				4765	features like scoped automatic variable sized arrays in C99.
				4766	</p>
				4767
				4768	<h5>Semantics:</h5>
				4769
				4770	<p>
				4771	This intrinsic returns a opaque pointer value that can be passed to <a
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	4772	href="#int_stackrestore"><tt>llvm.stackrestore</tt></a>. When an
Chris Lattner	57e1f39	2006-01-13 02:03:13 +0000	[diff] [blame]	4773	<tt>llvm.stackrestore</tt> intrinsic is executed with a value saved from
				4774	<tt>llvm.stacksave</tt>, it effectively restores the state of the stack to the
				4775	state it was in when the <tt>llvm.stacksave</tt> intrinsic executed. In
				4776	practice, this pops any <a href="#i_alloca">alloca</a> blocks from the stack
				4777	that were allocated after the <tt>llvm.stacksave</tt> was executed.
				4778	</p>
				4779
				4780	</div>
				4781
				4782	<!-- _______________________________________________________________________ -->
				4783	<div class="doc_subsubsection">
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	4784	<a name="int_stackrestore">'<tt>llvm.stackrestore</tt>' Intrinsic</a>
Chris Lattner	57e1f39	2006-01-13 02:03:13 +0000	[diff] [blame]	4785	</div>
				4786
				4787	<div class="doc_text">
				4788
				4789	<h5>Syntax:</h5>
				4790	<pre>
Anton Korobeynikov	ec43a06	2007-03-22 00:02:17 +0000	[diff] [blame]	4791	declare void @llvm.stackrestore(i8 * %ptr)
Chris Lattner	57e1f39	2006-01-13 02:03:13 +0000	[diff] [blame]	4792	</pre>
				4793
				4794	<h5>Overview:</h5>
				4795
				4796	<p>
				4797	The '<tt>llvm.stackrestore</tt>' intrinsic is used to restore the state of
				4798	the function stack to the state it was in when the corresponding <a
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	4799	href="#int_stacksave"><tt>llvm.stacksave</tt></a> intrinsic executed. This is
Chris Lattner	57e1f39	2006-01-13 02:03:13 +0000	[diff] [blame]	4800	useful for implementing language features like scoped automatic variable sized
				4801	arrays in C99.
				4802	</p>
				4803
				4804	<h5>Semantics:</h5>
				4805
				4806	<p>
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	4807	See the description for <a href="#int_stacksave"><tt>llvm.stacksave</tt></a>.
Chris Lattner	57e1f39	2006-01-13 02:03:13 +0000	[diff] [blame]	4808	</p>
				4809
				4810	</div>
				4811
				4812
				4813	<!-- _______________________________________________________________________ -->
				4814	<div class="doc_subsubsection">
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	4815	<a name="int_prefetch">'<tt>llvm.prefetch</tt>' Intrinsic</a>
Chris Lattner	9a9d7ac	2005-02-28 19:24:19 +0000	[diff] [blame]	4816	</div>
				4817
				4818	<div class="doc_text">
				4819
				4820	<h5>Syntax:</h5>
				4821	<pre>
Chris Lattner	1df4f75	2007-09-21 17:30:40 +0000	[diff] [blame]	4822	declare void @llvm.prefetch(i8* <address>, i32 <rw>, i32 <locality>)
Chris Lattner	9a9d7ac	2005-02-28 19:24:19 +0000	[diff] [blame]	4823	</pre>
				4824
				4825	<h5>Overview:</h5>
				4826
				4827
				4828	<p>
				4829	The '<tt>llvm.prefetch</tt>' intrinsic is a hint to the code generator to insert
John Criswell	fc6b895	2005-05-16 16:17:45 +0000	[diff] [blame]	4830	a prefetch instruction if supported; otherwise, it is a noop. Prefetches have
				4831	no
				4832	effect on the behavior of the program but can change its performance
Chris Lattner	2a61536	2005-02-28 19:47:14 +0000	[diff] [blame]	4833	characteristics.
Chris Lattner	9a9d7ac	2005-02-28 19:24:19 +0000	[diff] [blame]	4834	</p>
				4835
				4836	<h5>Arguments:</h5>
				4837
				4838	<p>
				4839	<tt>address</tt> is the address to be prefetched, <tt>rw</tt> is the specifier
				4840	determining if the fetch should be for a read (0) or write (1), and
				4841	<tt>locality</tt> is a temporal locality specifier ranging from (0) - no
Chris Lattner	aeffb4a	2005-03-07 20:31:38 +0000	[diff] [blame]	4842	locality, to (3) - extremely local keep in cache. The <tt>rw</tt> and
Chris Lattner	9a9d7ac	2005-02-28 19:24:19 +0000	[diff] [blame]	4843	<tt>locality</tt> arguments must be constant integers.
				4844	</p>
				4845
				4846	<h5>Semantics:</h5>
				4847
				4848	<p>
				4849	This intrinsic does not modify the behavior of the program. In particular,
				4850	prefetches cannot trap and do not produce a value. On targets that support this
				4851	intrinsic, the prefetch can provide hints to the processor cache for better
				4852	performance.
				4853	</p>
				4854
				4855	</div>
				4856
Andrew Lenharth	7f4ec3b	2005-03-28 20:05:49 +0000	[diff] [blame]	4857	<!-- _______________________________________________________________________ -->
				4858	<div class="doc_subsubsection">
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	4859	<a name="int_pcmarker">'<tt>llvm.pcmarker</tt>' Intrinsic</a>
Andrew Lenharth	7f4ec3b	2005-03-28 20:05:49 +0000	[diff] [blame]	4860	</div>
				4861
				4862	<div class="doc_text">
				4863
				4864	<h5>Syntax:</h5>
				4865	<pre>
Chris Lattner	1df4f75	2007-09-21 17:30:40 +0000	[diff] [blame]	4866	declare void @llvm.pcmarker(i32 <id>)
Andrew Lenharth	7f4ec3b	2005-03-28 20:05:49 +0000	[diff] [blame]	4867	</pre>
				4868
				4869	<h5>Overview:</h5>
				4870
				4871
				4872	<p>
John Criswell	fc6b895	2005-05-16 16:17:45 +0000	[diff] [blame]	4873	The '<tt>llvm.pcmarker</tt>' intrinsic is a method to export a Program Counter
Chris Lattner	d3eda89	2008-08-05 18:29:16 +0000	[diff] [blame]	4874	(PC) in a region of
				4875	code to simulators and other tools. The method is target specific, but it is
				4876	expected that the marker will use exported symbols to transmit the PC of the
				4877	marker.
				4878	The marker makes no guarantees that it will remain with any specific instruction
				4879	after optimizations. It is possible that the presence of a marker will inhibit
Chris Lattner	b3e7afd	2006-03-24 07:16:10 +0000	[diff] [blame]	4880	optimizations. The intended use is to be inserted after optimizations to allow
John Criswell	fc6b895	2005-05-16 16:17:45 +0000	[diff] [blame]	4881	correlations of simulation runs.
Andrew Lenharth	7f4ec3b	2005-03-28 20:05:49 +0000	[diff] [blame]	4882	</p>
				4883
				4884	<h5>Arguments:</h5>
				4885
				4886	<p>
				4887	<tt>id</tt> is a numerical id identifying the marker.
				4888	</p>
				4889
				4890	<h5>Semantics:</h5>
				4891
				4892	<p>
				4893	This intrinsic does not modify the behavior of the program. Backends that do not
				4894	support this intrinisic may ignore it.
				4895	</p>
				4896
				4897	</div>
				4898
Andrew Lenharth	51b8d54	2005-11-11 16:47:30 +0000	[diff] [blame]	4899	<!-- _______________________________________________________________________ -->
				4900	<div class="doc_subsubsection">
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	4901	<a name="int_readcyclecounter">'<tt>llvm.readcyclecounter</tt>' Intrinsic</a>
Andrew Lenharth	51b8d54	2005-11-11 16:47:30 +0000	[diff] [blame]	4902	</div>
				4903
				4904	<div class="doc_text">
				4905
				4906	<h5>Syntax:</h5>
				4907	<pre>
Anton Korobeynikov	ec43a06	2007-03-22 00:02:17 +0000	[diff] [blame]	4908	declare i64 @llvm.readcyclecounter( )
Andrew Lenharth	51b8d54	2005-11-11 16:47:30 +0000	[diff] [blame]	4909	</pre>
				4910
				4911	<h5>Overview:</h5>
				4912
				4913
				4914	<p>
				4915	The '<tt>llvm.readcyclecounter</tt>' intrinsic provides access to the cycle
				4916	counter register (or similar low latency, high accuracy clocks) on those targets
				4917	that support it. On X86, it should map to RDTSC. On Alpha, it should map to RPCC.
				4918	As the backing counters overflow quickly (on the order of 9 seconds on alpha), this
				4919	should only be used for small timings.
				4920	</p>
				4921
				4922	<h5>Semantics:</h5>
				4923
				4924	<p>
				4925	When directly supported, reading the cycle counter should not modify any memory.
				4926	Implementations are allowed to either return a application specific value or a
				4927	system wide value. On backends without support, this is lowered to a constant 0.
				4928	</p>
				4929
				4930	</div>
				4931
Chris Lattner	1061064	2004-02-14 04:08:35 +0000	[diff] [blame]	4932	<!-- ======================================================================= -->
				4933	<div class="doc_subsection">
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4934	<a name="int_libc">Standard C Library Intrinsics</a>
				4935	</div>
				4936
				4937	<div class="doc_text">
				4938	<p>
Chris Lattner	1061064	2004-02-14 04:08:35 +0000	[diff] [blame]	4939	LLVM provides intrinsics for a few important standard C library functions.
				4940	These intrinsics allow source-language front-ends to pass information about the
				4941	alignment of the pointer arguments to the code generator, providing opportunity
				4942	for more efficient code generation.
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4943	</p>
				4944
				4945	</div>
				4946
				4947	<!-- _______________________________________________________________________ -->
				4948	<div class="doc_subsubsection">
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	4949	<a name="int_memcpy">'<tt>llvm.memcpy</tt>' Intrinsic</a>
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4950	</div>
				4951
				4952	<div class="doc_text">
				4953
				4954	<h5>Syntax:</h5>
				4955	<pre>
Anton Korobeynikov	ec43a06	2007-03-22 00:02:17 +0000	[diff] [blame]	4956	declare void @llvm.memcpy.i32(i8 * <dest>, i8 * <src>,
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	4957	i32 <len>, i32 <align>)
Anton Korobeynikov	ec43a06	2007-03-22 00:02:17 +0000	[diff] [blame]	4958	declare void @llvm.memcpy.i64(i8 * <dest>, i8 * <src>,
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	4959	i64 <len>, i32 <align>)
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4960	</pre>
				4961
				4962	<h5>Overview:</h5>
				4963
				4964	<p>
Chris Lattner	5b310c3	2006-03-03 00:07:20 +0000	[diff] [blame]	4965	The '<tt>llvm.memcpy.*</tt>' intrinsics copy a block of memory from the source
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4966	location to the destination location.
				4967	</p>
				4968
				4969	<p>
Chris Lattner	5b310c3	2006-03-03 00:07:20 +0000	[diff] [blame]	4970	Note that, unlike the standard libc function, the <tt>llvm.memcpy.*</tt>
				4971	intrinsics do not return a value, and takes an extra alignment argument.
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4972	</p>
				4973
				4974	<h5>Arguments:</h5>
				4975
				4976	<p>
				4977	The first argument is a pointer to the destination, the second is a pointer to
Chris Lattner	5b310c3	2006-03-03 00:07:20 +0000	[diff] [blame]	4978	the source. The third argument is an integer argument
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4979	specifying the number of bytes to copy, and the fourth argument is the alignment
				4980	of the source and destination locations.
				4981	</p>
				4982
Chris Lattner	3301ced	2004-02-12 21:18:15 +0000	[diff] [blame]	4983	<p>
				4984	If the call to this intrinisic has an alignment value that is not 0 or 1, then
Chris Lattner	f0afc2c	2006-03-04 00:02:10 +0000	[diff] [blame]	4985	the caller guarantees that both the source and destination pointers are aligned
				4986	to that boundary.
Chris Lattner	3301ced	2004-02-12 21:18:15 +0000	[diff] [blame]	4987	</p>
				4988
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4989	<h5>Semantics:</h5>
				4990
				4991	<p>
Chris Lattner	5b310c3	2006-03-03 00:07:20 +0000	[diff] [blame]	4992	The '<tt>llvm.memcpy.*</tt>' intrinsics copy a block of memory from the source
Chris Lattner	33aec9e	2004-02-12 17:01:32 +0000	[diff] [blame]	4993	location to the destination location, which are not allowed to overlap. It
				4994	copies "len" bytes of memory over. If the argument is known to be aligned to
				4995	some boundary, this can be specified as the fourth argument, otherwise it should
				4996	be set to 0 or 1.
				4997	</p>
				4998	</div>
				4999
				5000
Chris Lattner	0eb51b4	2004-02-12 18:10:10 +0000	[diff] [blame]	5001	<!-- _______________________________________________________________________ -->
				5002	<div class="doc_subsubsection">
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	5003	<a name="int_memmove">'<tt>llvm.memmove</tt>' Intrinsic</a>
Chris Lattner	0eb51b4	2004-02-12 18:10:10 +0000	[diff] [blame]	5004	</div>
				5005
				5006	<div class="doc_text">
				5007
				5008	<h5>Syntax:</h5>
				5009	<pre>
Anton Korobeynikov	ec43a06	2007-03-22 00:02:17 +0000	[diff] [blame]	5010	declare void @llvm.memmove.i32(i8 * <dest>, i8 * <src>,
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	5011	i32 <len>, i32 <align>)
Anton Korobeynikov	ec43a06	2007-03-22 00:02:17 +0000	[diff] [blame]	5012	declare void @llvm.memmove.i64(i8 * <dest>, i8 * <src>,
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	5013	i64 <len>, i32 <align>)
Chris Lattner	0eb51b4	2004-02-12 18:10:10 +0000	[diff] [blame]	5014	</pre>
				5015
				5016	<h5>Overview:</h5>
				5017
				5018	<p>
Chris Lattner	5b310c3	2006-03-03 00:07:20 +0000	[diff] [blame]	5019	The '<tt>llvm.memmove.*</tt>' intrinsics move a block of memory from the source
				5020	location to the destination location. It is similar to the
Chris Lattner	4b2cbcf	2008-01-06 19:51:52 +0000	[diff] [blame]	5021	'<tt>llvm.memcpy</tt>' intrinsic but allows the two memory locations to overlap.
Chris Lattner	0eb51b4	2004-02-12 18:10:10 +0000	[diff] [blame]	5022	</p>
				5023
				5024	<p>
Chris Lattner	5b310c3	2006-03-03 00:07:20 +0000	[diff] [blame]	5025	Note that, unlike the standard libc function, the <tt>llvm.memmove.*</tt>
				5026	intrinsics do not return a value, and takes an extra alignment argument.
Chris Lattner	0eb51b4	2004-02-12 18:10:10 +0000	[diff] [blame]	5027	</p>
				5028
				5029	<h5>Arguments:</h5>
				5030
				5031	<p>
				5032	The first argument is a pointer to the destination, the second is a pointer to
Chris Lattner	5b310c3	2006-03-03 00:07:20 +0000	[diff] [blame]	5033	the source. The third argument is an integer argument
Chris Lattner	0eb51b4	2004-02-12 18:10:10 +0000	[diff] [blame]	5034	specifying the number of bytes to copy, and the fourth argument is the alignment
				5035	of the source and destination locations.
				5036	</p>
				5037
Chris Lattner	3301ced	2004-02-12 21:18:15 +0000	[diff] [blame]	5038	<p>
				5039	If the call to this intrinisic has an alignment value that is not 0 or 1, then
Chris Lattner	f0afc2c	2006-03-04 00:02:10 +0000	[diff] [blame]	5040	the caller guarantees that the source and destination pointers are aligned to
				5041	that boundary.
Chris Lattner	3301ced	2004-02-12 21:18:15 +0000	[diff] [blame]	5042	</p>
				5043
Chris Lattner	0eb51b4	2004-02-12 18:10:10 +0000	[diff] [blame]	5044	<h5>Semantics:</h5>
				5045
				5046	<p>
Chris Lattner	5b310c3	2006-03-03 00:07:20 +0000	[diff] [blame]	5047	The '<tt>llvm.memmove.*</tt>' intrinsics copy a block of memory from the source
Chris Lattner	0eb51b4	2004-02-12 18:10:10 +0000	[diff] [blame]	5048	location to the destination location, which may overlap. It
				5049	copies "len" bytes of memory over. If the argument is known to be aligned to
				5050	some boundary, this can be specified as the fourth argument, otherwise it should
				5051	be set to 0 or 1.
				5052	</p>
				5053	</div>
				5054
Chris Lattner	8ff7590	2004-01-06 05:31:32 +0000	[diff] [blame]	5055
Chris Lattner	1061064	2004-02-14 04:08:35 +0000	[diff] [blame]	5056	<!-- _______________________________________________________________________ -->
				5057	<div class="doc_subsubsection">
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	5058	<a name="int_memset">'<tt>llvm.memset.*</tt>' Intrinsics</a>
Chris Lattner	1061064	2004-02-14 04:08:35 +0000	[diff] [blame]	5059	</div>
				5060
				5061	<div class="doc_text">
				5062
				5063	<h5>Syntax:</h5>
				5064	<pre>
Anton Korobeynikov	ec43a06	2007-03-22 00:02:17 +0000	[diff] [blame]	5065	declare void @llvm.memset.i32(i8 * <dest>, i8 <val>,
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	5066	i32 <len>, i32 <align>)
Anton Korobeynikov	ec43a06	2007-03-22 00:02:17 +0000	[diff] [blame]	5067	declare void @llvm.memset.i64(i8 * <dest>, i8 <val>,
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	5068	i64 <len>, i32 <align>)
Chris Lattner	1061064	2004-02-14 04:08:35 +0000	[diff] [blame]	5069	</pre>
				5070
				5071	<h5>Overview:</h5>
				5072
				5073	<p>
Chris Lattner	5b310c3	2006-03-03 00:07:20 +0000	[diff] [blame]	5074	The '<tt>llvm.memset.*</tt>' intrinsics fill a block of memory with a particular
Chris Lattner	1061064	2004-02-14 04:08:35 +0000	[diff] [blame]	5075	byte value.
				5076	</p>
				5077
				5078	<p>
				5079	Note that, unlike the standard libc function, the <tt>llvm.memset</tt> intrinsic
				5080	does not return a value, and takes an extra alignment argument.
				5081	</p>
				5082
				5083	<h5>Arguments:</h5>
				5084
				5085	<p>
				5086	The first argument is a pointer to the destination to fill, the second is the
Chris Lattner	5b310c3	2006-03-03 00:07:20 +0000	[diff] [blame]	5087	byte value to fill it with, the third argument is an integer
Chris Lattner	1061064	2004-02-14 04:08:35 +0000	[diff] [blame]	5088	argument specifying the number of bytes to fill, and the fourth argument is the
				5089	known alignment of destination location.
				5090	</p>
				5091
				5092	<p>
				5093	If the call to this intrinisic has an alignment value that is not 0 or 1, then
Chris Lattner	f0afc2c	2006-03-04 00:02:10 +0000	[diff] [blame]	5094	the caller guarantees that the destination pointer is aligned to that boundary.
Chris Lattner	1061064	2004-02-14 04:08:35 +0000	[diff] [blame]	5095	</p>
				5096
				5097	<h5>Semantics:</h5>
				5098
				5099	<p>
Chris Lattner	5b310c3	2006-03-03 00:07:20 +0000	[diff] [blame]	5100	The '<tt>llvm.memset.*</tt>' intrinsics fill "len" bytes of memory starting at
				5101	the
Chris Lattner	1061064	2004-02-14 04:08:35 +0000	[diff] [blame]	5102	destination location. If the argument is known to be aligned to some boundary,
				5103	this can be specified as the fourth argument, otherwise it should be set to 0 or
				5104	1.
				5105	</p>
				5106	</div>
				5107
				5108
Chris Lattner	3200628	2004-06-11 02:28:03 +0000	[diff] [blame]	5109	<!-- _______________________________________________________________________ -->
				5110	<div class="doc_subsubsection">
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	5111	<a name="int_sqrt">'<tt>llvm.sqrt.*</tt>' Intrinsic</a>
Chris Lattner	a4d7414	2005-07-21 01:29:16 +0000	[diff] [blame]	5112	</div>
				5113
				5114	<div class="doc_text">
				5115
				5116	<h5>Syntax:</h5>
Dale Johannesen	408f9c1	2007-10-02 17:47:38 +0000	[diff] [blame]	5117	<p>This is an overloaded intrinsic. You can use <tt>llvm.sqrt</tt> on any
Dan Gohman	91c284c	2007-10-15 20:30:11 +0000	[diff] [blame]	5118	floating point or vector of floating point type. Not all targets support all
				5119	types however.
Chris Lattner	a4d7414	2005-07-21 01:29:16 +0000	[diff] [blame]	5120	<pre>
Dale Johannesen	408f9c1	2007-10-02 17:47:38 +0000	[diff] [blame]	5121	declare float @llvm.sqrt.f32(float %Val)
				5122	declare double @llvm.sqrt.f64(double %Val)
				5123	declare x86_fp80 @llvm.sqrt.f80(x86_fp80 %Val)
				5124	declare fp128 @llvm.sqrt.f128(fp128 %Val)
				5125	declare ppc_fp128 @llvm.sqrt.ppcf128(ppc_fp128 %Val)
Chris Lattner	a4d7414	2005-07-21 01:29:16 +0000	[diff] [blame]	5126	</pre>
				5127
				5128	<h5>Overview:</h5>
				5129
				5130	<p>
Reid Spencer	0b11820	2006-01-16 21:12:35 +0000	[diff] [blame]	5131	The '<tt>llvm.sqrt</tt>' intrinsics return the sqrt of the specified operand,
Dan Gohman	91c284c	2007-10-15 20:30:11 +0000	[diff] [blame]	5132	returning the same value as the libm '<tt>sqrt</tt>' functions would. Unlike
Chris Lattner	a4d7414	2005-07-21 01:29:16 +0000	[diff] [blame]	5133	<tt>sqrt</tt> in libm, however, <tt>llvm.sqrt</tt> has undefined behavior for
Chris Lattner	103e2d7	2008-01-29 07:00:44 +0000	[diff] [blame]	5134	negative numbers other than -0.0 (which allows for better optimization, because
				5135	there is no need to worry about errno being set). <tt>llvm.sqrt(-0.0)</tt> is
				5136	defined to return -0.0 like IEEE sqrt.
Chris Lattner	a4d7414	2005-07-21 01:29:16 +0000	[diff] [blame]	5137	</p>
				5138
				5139	<h5>Arguments:</h5>
				5140
				5141	<p>
				5142	The argument and return value are floating point numbers of the same type.
				5143	</p>
				5144
				5145	<h5>Semantics:</h5>
				5146
				5147	<p>
Dan Gohman	d6257fe	2007-07-16 14:37:41 +0000	[diff] [blame]	5148	This function returns the sqrt of the specified operand if it is a nonnegative
Chris Lattner	a4d7414	2005-07-21 01:29:16 +0000	[diff] [blame]	5149	floating point number.
				5150	</p>
				5151	</div>
				5152
Chris Lattner	f4d252d	2006-09-08 06:34:02 +0000	[diff] [blame]	5153	<!-- _______________________________________________________________________ -->
				5154	<div class="doc_subsubsection">
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	5155	<a name="int_powi">'<tt>llvm.powi.*</tt>' Intrinsic</a>
Chris Lattner	f4d252d	2006-09-08 06:34:02 +0000	[diff] [blame]	5156	</div>
				5157
				5158	<div class="doc_text">
				5159
				5160	<h5>Syntax:</h5>
Dale Johannesen	408f9c1	2007-10-02 17:47:38 +0000	[diff] [blame]	5161	<p>This is an overloaded intrinsic. You can use <tt>llvm.powi</tt> on any
Dan Gohman	91c284c	2007-10-15 20:30:11 +0000	[diff] [blame]	5162	floating point or vector of floating point type. Not all targets support all
				5163	types however.
Chris Lattner	f4d252d	2006-09-08 06:34:02 +0000	[diff] [blame]	5164	<pre>
Dale Johannesen	408f9c1	2007-10-02 17:47:38 +0000	[diff] [blame]	5165	declare float @llvm.powi.f32(float %Val, i32 %power)
				5166	declare double @llvm.powi.f64(double %Val, i32 %power)
				5167	declare x86_fp80 @llvm.powi.f80(x86_fp80 %Val, i32 %power)
				5168	declare fp128 @llvm.powi.f128(fp128 %Val, i32 %power)
				5169	declare ppc_fp128 @llvm.powi.ppcf128(ppc_fp128 %Val, i32 %power)
Chris Lattner	f4d252d	2006-09-08 06:34:02 +0000	[diff] [blame]	5170	</pre>
				5171
				5172	<h5>Overview:</h5>
				5173
				5174	<p>
				5175	The '<tt>llvm.powi.*</tt>' intrinsics return the first operand raised to the
				5176	specified (positive or negative) power. The order of evaluation of
Dan Gohman	91c284c	2007-10-15 20:30:11 +0000	[diff] [blame]	5177	multiplications is not defined. When a vector of floating point type is
				5178	used, the second argument remains a scalar integer value.
Chris Lattner	f4d252d	2006-09-08 06:34:02 +0000	[diff] [blame]	5179	</p>
				5180
				5181	<h5>Arguments:</h5>
				5182
				5183	<p>
				5184	The second argument is an integer power, and the first is a value to raise to
				5185	that power.
				5186	</p>
				5187
				5188	<h5>Semantics:</h5>
				5189
				5190	<p>
				5191	This function returns the first value raised to the second power with an
				5192	unspecified sequence of rounding operations.</p>
				5193	</div>
				5194
Dan Gohman	91c284c	2007-10-15 20:30:11 +0000	[diff] [blame]	5195	<!-- _______________________________________________________________________ -->
				5196	<div class="doc_subsubsection">
				5197	<a name="int_sin">'<tt>llvm.sin.*</tt>' Intrinsic</a>
				5198	</div>
				5199
				5200	<div class="doc_text">
				5201
				5202	<h5>Syntax:</h5>
				5203	<p>This is an overloaded intrinsic. You can use <tt>llvm.sin</tt> on any
				5204	floating point or vector of floating point type. Not all targets support all
				5205	types however.
				5206	<pre>
				5207	declare float @llvm.sin.f32(float %Val)
				5208	declare double @llvm.sin.f64(double %Val)
				5209	declare x86_fp80 @llvm.sin.f80(x86_fp80 %Val)
				5210	declare fp128 @llvm.sin.f128(fp128 %Val)
				5211	declare ppc_fp128 @llvm.sin.ppcf128(ppc_fp128 %Val)
				5212	</pre>
				5213
				5214	<h5>Overview:</h5>
				5215
				5216	<p>
				5217	The '<tt>llvm.sin.*</tt>' intrinsics return the sine of the operand.
				5218	</p>
				5219
				5220	<h5>Arguments:</h5>
				5221
				5222	<p>
				5223	The argument and return value are floating point numbers of the same type.
				5224	</p>
				5225
				5226	<h5>Semantics:</h5>
				5227
				5228	<p>
				5229	This function returns the sine of the specified operand, returning the
				5230	same values as the libm <tt>sin</tt> functions would, and handles error
Dan Gohman	ba83b7e	2007-10-17 18:05:13 +0000	[diff] [blame]	5231	conditions in the same way.</p>
Dan Gohman	91c284c	2007-10-15 20:30:11 +0000	[diff] [blame]	5232	</div>
				5233
				5234	<!-- _______________________________________________________________________ -->
				5235	<div class="doc_subsubsection">
				5236	<a name="int_cos">'<tt>llvm.cos.*</tt>' Intrinsic</a>
				5237	</div>
				5238
				5239	<div class="doc_text">
				5240
				5241	<h5>Syntax:</h5>
				5242	<p>This is an overloaded intrinsic. You can use <tt>llvm.cos</tt> on any
				5243	floating point or vector of floating point type. Not all targets support all
				5244	types however.
				5245	<pre>
				5246	declare float @llvm.cos.f32(float %Val)
				5247	declare double @llvm.cos.f64(double %Val)
				5248	declare x86_fp80 @llvm.cos.f80(x86_fp80 %Val)
				5249	declare fp128 @llvm.cos.f128(fp128 %Val)
				5250	declare ppc_fp128 @llvm.cos.ppcf128(ppc_fp128 %Val)
				5251	</pre>
				5252
				5253	<h5>Overview:</h5>
				5254
				5255	<p>
				5256	The '<tt>llvm.cos.*</tt>' intrinsics return the cosine of the operand.
				5257	</p>
				5258
				5259	<h5>Arguments:</h5>
				5260
				5261	<p>
				5262	The argument and return value are floating point numbers of the same type.
				5263	</p>
				5264
				5265	<h5>Semantics:</h5>
				5266
				5267	<p>
				5268	This function returns the cosine of the specified operand, returning the
				5269	same values as the libm <tt>cos</tt> functions would, and handles error
Dan Gohman	ba83b7e	2007-10-17 18:05:13 +0000	[diff] [blame]	5270	conditions in the same way.</p>
Dan Gohman	91c284c	2007-10-15 20:30:11 +0000	[diff] [blame]	5271	</div>
				5272
				5273	<!-- _______________________________________________________________________ -->
				5274	<div class="doc_subsubsection">
				5275	<a name="int_pow">'<tt>llvm.pow.*</tt>' Intrinsic</a>
				5276	</div>
				5277
				5278	<div class="doc_text">
				5279
				5280	<h5>Syntax:</h5>
				5281	<p>This is an overloaded intrinsic. You can use <tt>llvm.pow</tt> on any
				5282	floating point or vector of floating point type. Not all targets support all
				5283	types however.
				5284	<pre>
				5285	declare float @llvm.pow.f32(float %Val, float %Power)
				5286	declare double @llvm.pow.f64(double %Val, double %Power)
				5287	declare x86_fp80 @llvm.pow.f80(x86_fp80 %Val, x86_fp80 %Power)
				5288	declare fp128 @llvm.pow.f128(fp128 %Val, fp128 %Power)
				5289	declare ppc_fp128 @llvm.pow.ppcf128(ppc_fp128 %Val, ppc_fp128 Power)
				5290	</pre>
				5291
				5292	<h5>Overview:</h5>
				5293
				5294	<p>
				5295	The '<tt>llvm.pow.*</tt>' intrinsics return the first operand raised to the
				5296	specified (positive or negative) power.
				5297	</p>
				5298
				5299	<h5>Arguments:</h5>
				5300
				5301	<p>
				5302	The second argument is a floating point power, and the first is a value to
				5303	raise to that power.
				5304	</p>
				5305
				5306	<h5>Semantics:</h5>
				5307
				5308	<p>
				5309	This function returns the first value raised to the second power,
				5310	returning the
				5311	same values as the libm <tt>pow</tt> functions would, and handles error
Dan Gohman	ba83b7e	2007-10-17 18:05:13 +0000	[diff] [blame]	5312	conditions in the same way.</p>
Dan Gohman	91c284c	2007-10-15 20:30:11 +0000	[diff] [blame]	5313	</div>
				5314
Chris Lattner	f4d252d	2006-09-08 06:34:02 +0000	[diff] [blame]	5315
Andrew Lenharth	ec370fd	2005-05-03 18:01:48 +0000	[diff] [blame]	5316	<!-- ======================================================================= -->
				5317	<div class="doc_subsection">
Nate Begeman	7e36c47	2006-01-13 23:26:38 +0000	[diff] [blame]	5318	<a name="int_manip">Bit Manipulation Intrinsics</a>
Andrew Lenharth	ec370fd	2005-05-03 18:01:48 +0000	[diff] [blame]	5319	</div>
				5320
				5321	<div class="doc_text">
				5322	<p>
Nate Begeman	7e36c47	2006-01-13 23:26:38 +0000	[diff] [blame]	5323	LLVM provides intrinsics for a few important bit manipulation operations.
Andrew Lenharth	ec370fd	2005-05-03 18:01:48 +0000	[diff] [blame]	5324	These allow efficient code generation for some algorithms.
				5325	</p>
				5326
				5327	</div>
				5328
				5329	<!-- _______________________________________________________________________ -->
				5330	<div class="doc_subsubsection">
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	5331	<a name="int_bswap">'<tt>llvm.bswap.*</tt>' Intrinsics</a>
Nate Begeman	7e36c47	2006-01-13 23:26:38 +0000	[diff] [blame]	5332	</div>
				5333
				5334	<div class="doc_text">
				5335
				5336	<h5>Syntax:</h5>
Reid Spencer	409e28f	2007-04-01 08:04:23 +0000	[diff] [blame]	5337	<p>This is an overloaded intrinsic function. You can use bswap on any integer
Chandler Carruth	6994040	2007-08-04 01:51:18 +0000	[diff] [blame]	5338	type that is an even number of bytes (i.e. BitWidth % 16 == 0).
Nate Begeman	7e36c47	2006-01-13 23:26:38 +0000	[diff] [blame]	5339	<pre>
Chandler Carruth	6994040	2007-08-04 01:51:18 +0000	[diff] [blame]	5340	declare i16 @llvm.bswap.i16(i16 <id>)
				5341	declare i32 @llvm.bswap.i32(i32 <id>)
				5342	declare i64 @llvm.bswap.i64(i64 <id>)
Nate Begeman	7e36c47	2006-01-13 23:26:38 +0000	[diff] [blame]	5343	</pre>
				5344
				5345	<h5>Overview:</h5>
				5346
				5347	<p>
Reid Spencer	338ea09	2007-04-02 02:25:19 +0000	[diff] [blame]	5348	The '<tt>llvm.bswap</tt>' family of intrinsics is used to byte swap integer
Reid Spencer	409e28f	2007-04-01 08:04:23 +0000	[diff] [blame]	5349	values with an even number of bytes (positive multiple of 16 bits). These are
				5350	useful for performing operations on data that is not in the target's native
				5351	byte order.
Nate Begeman	7e36c47	2006-01-13 23:26:38 +0000	[diff] [blame]	5352	</p>
				5353
				5354	<h5>Semantics:</h5>
				5355
				5356	<p>
Chandler Carruth	6994040	2007-08-04 01:51:18 +0000	[diff] [blame]	5357	The <tt>llvm.bswap.i16</tt> intrinsic returns an i16 value that has the high
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	5358	and low byte of the input i16 swapped. Similarly, the <tt>llvm.bswap.i32</tt>
				5359	intrinsic returns an i32 value that has the four bytes of the input i32
				5360	swapped, so that if the input bytes are numbered 0, 1, 2, 3 then the returned
Chandler Carruth	6994040	2007-08-04 01:51:18 +0000	[diff] [blame]	5361	i32 will have its bytes in 3, 2, 1, 0 order. The <tt>llvm.bswap.i48</tt>,
				5362	<tt>llvm.bswap.i64</tt> and other intrinsics extend this concept to
Reid Spencer	409e28f	2007-04-01 08:04:23 +0000	[diff] [blame]	5363	additional even-byte lengths (6 bytes, 8 bytes and more, respectively).
Nate Begeman	7e36c47	2006-01-13 23:26:38 +0000	[diff] [blame]	5364	</p>
				5365
				5366	</div>
				5367
				5368	<!-- _______________________________________________________________________ -->
				5369	<div class="doc_subsubsection">
Reid Spencer	0b11820	2006-01-16 21:12:35 +0000	[diff] [blame]	5370	<a name="int_ctpop">'<tt>llvm.ctpop.*</tt>' Intrinsic</a>
Andrew Lenharth	ec370fd	2005-05-03 18:01:48 +0000	[diff] [blame]	5371	</div>
				5372
				5373	<div class="doc_text">
				5374
				5375	<h5>Syntax:</h5>
Reid Spencer	409e28f	2007-04-01 08:04:23 +0000	[diff] [blame]	5376	<p>This is an overloaded intrinsic. You can use llvm.ctpop on any integer bit
				5377	width. Not all targets support all bit widths however.
Andrew Lenharth	ec370fd	2005-05-03 18:01:48 +0000	[diff] [blame]	5378	<pre>
Chandler Carruth	6994040	2007-08-04 01:51:18 +0000	[diff] [blame]	5379	declare i8 @llvm.ctpop.i8 (i8 <src>)
				5380	declare i16 @llvm.ctpop.i16(i16 <src>)
Anton Korobeynikov	ec43a06	2007-03-22 00:02:17 +0000	[diff] [blame]	5381	declare i32 @llvm.ctpop.i32(i32 <src>)
Chandler Carruth	6994040	2007-08-04 01:51:18 +0000	[diff] [blame]	5382	declare i64 @llvm.ctpop.i64(i64 <src>)
				5383	declare i256 @llvm.ctpop.i256(i256 <src>)
Andrew Lenharth	ec370fd	2005-05-03 18:01:48 +0000	[diff] [blame]	5384	</pre>
				5385
				5386	<h5>Overview:</h5>
				5387
				5388	<p>
Chris Lattner	ec6cb61	2006-01-16 22:38:59 +0000	[diff] [blame]	5389	The '<tt>llvm.ctpop</tt>' family of intrinsics counts the number of bits set in a
				5390	value.
Andrew Lenharth	ec370fd	2005-05-03 18:01:48 +0000	[diff] [blame]	5391	</p>
				5392
				5393	<h5>Arguments:</h5>
				5394
				5395	<p>
Chris Lattner	cfe6b37	2005-05-07 01:46:40 +0000	[diff] [blame]	5396	The only argument is the value to be counted. The argument may be of any
Reid Spencer	a517338	2007-01-04 16:43:23 +0000	[diff] [blame]	5397	integer type. The return type must match the argument type.
Andrew Lenharth	ec370fd	2005-05-03 18:01:48 +0000	[diff] [blame]	5398	</p>
				5399
				5400	<h5>Semantics:</h5>
				5401
				5402	<p>
				5403	The '<tt>llvm.ctpop</tt>' intrinsic counts the 1's in a variable.
				5404	</p>
				5405	</div>
				5406
				5407	<!-- _______________________________________________________________________ -->
				5408	<div class="doc_subsubsection">
Chris Lattner	8a886be	2006-01-16 22:34:14 +0000	[diff] [blame]	5409	<a name="int_ctlz">'<tt>llvm.ctlz.*</tt>' Intrinsic</a>
Andrew Lenharth	ec370fd	2005-05-03 18:01:48 +0000	[diff] [blame]	5410	</div>
				5411
				5412	<div class="doc_text">
				5413
				5414	<h5>Syntax:</h5>
Reid Spencer	409e28f	2007-04-01 08:04:23 +0000	[diff] [blame]	5415	<p>This is an overloaded intrinsic. You can use <tt>llvm.ctlz</tt> on any
				5416	integer bit width. Not all targets support all bit widths however.
Andrew Lenharth	ec370fd	2005-05-03 18:01:48 +0000	[diff] [blame]	5417	<pre>
Chandler Carruth	6994040	2007-08-04 01:51:18 +0000	[diff] [blame]	5418	declare i8 @llvm.ctlz.i8 (i8 <src>)
				5419	declare i16 @llvm.ctlz.i16(i16 <src>)
Anton Korobeynikov	ec43a06	2007-03-22 00:02:17 +0000	[diff] [blame]	5420	declare i32 @llvm.ctlz.i32(i32 <src>)
Chandler Carruth	6994040	2007-08-04 01:51:18 +0000	[diff] [blame]	5421	declare i64 @llvm.ctlz.i64(i64 <src>)
				5422	declare i256 @llvm.ctlz.i256(i256 <src>)
Andrew Lenharth	ec370fd	2005-05-03 18:01:48 +0000	[diff] [blame]	5423	</pre>
				5424
				5425	<h5>Overview:</h5>
				5426
				5427	<p>
Reid Spencer	0b11820	2006-01-16 21:12:35 +0000	[diff] [blame]	5428	The '<tt>llvm.ctlz</tt>' family of intrinsic functions counts the number of
				5429	leading zeros in a variable.
Andrew Lenharth	ec370fd	2005-05-03 18:01:48 +0000	[diff] [blame]	5430	</p>
				5431
				5432	<h5>Arguments:</h5>
				5433
				5434	<p>
Chris Lattner	cfe6b37	2005-05-07 01:46:40 +0000	[diff] [blame]	5435	The only argument is the value to be counted. The argument may be of any
Reid Spencer	a517338	2007-01-04 16:43:23 +0000	[diff] [blame]	5436	integer type. The return type must match the argument type.
Andrew Lenharth	ec370fd	2005-05-03 18:01:48 +0000	[diff] [blame]	5437	</p>
				5438
				5439	<h5>Semantics:</h5>
				5440
				5441	<p>
Chris Lattner	eff29ab	2005-05-15 19:39:26 +0000	[diff] [blame]	5442	The '<tt>llvm.ctlz</tt>' intrinsic counts the leading (most significant) zeros
				5443	in a variable. If the src == 0 then the result is the size in bits of the type
Reid Spencer	ca86e16	2006-12-31 07:07:53 +0000	[diff] [blame]	5444	of src. For example, <tt>llvm.ctlz(i32 2) = 30</tt>.
Andrew Lenharth	ec370fd	2005-05-03 18:01:48 +0000	[diff] [blame]	5445	</p>
				5446	</div>
Chris Lattner	3200628	2004-06-11 02:28:03 +0000	[diff] [blame]	5447
				5448
Chris Lattner	eff29ab	2005-05-15 19:39:26 +0000	[diff] [blame]	5449
				5450	<!-- _______________________________________________________________________ -->
				5451	<div class="doc_subsubsection">
Chris Lattner	8a886be	2006-01-16 22:34:14 +0000	[diff] [blame]	5452	<a name="int_cttz">'<tt>llvm.cttz.*</tt>' Intrinsic</a>
Chris Lattner	eff29ab	2005-05-15 19:39:26 +0000	[diff] [blame]	5453	</div>
				5454
				5455	<div class="doc_text">
				5456
				5457	<h5>Syntax:</h5>
Reid Spencer	409e28f	2007-04-01 08:04:23 +0000	[diff] [blame]	5458	<p>This is an overloaded intrinsic. You can use <tt>llvm.cttz</tt> on any
				5459	integer bit width. Not all targets support all bit widths however.
Chris Lattner	eff29ab	2005-05-15 19:39:26 +0000	[diff] [blame]	5460	<pre>
Chandler Carruth	6994040	2007-08-04 01:51:18 +0000	[diff] [blame]	5461	declare i8 @llvm.cttz.i8 (i8 <src>)
				5462	declare i16 @llvm.cttz.i16(i16 <src>)
Anton Korobeynikov	ec43a06	2007-03-22 00:02:17 +0000	[diff] [blame]	5463	declare i32 @llvm.cttz.i32(i32 <src>)
Chandler Carruth	6994040	2007-08-04 01:51:18 +0000	[diff] [blame]	5464	declare i64 @llvm.cttz.i64(i64 <src>)
				5465	declare i256 @llvm.cttz.i256(i256 <src>)
Chris Lattner	eff29ab	2005-05-15 19:39:26 +0000	[diff] [blame]	5466	</pre>
				5467
				5468	<h5>Overview:</h5>
				5469
				5470	<p>
Reid Spencer	0b11820	2006-01-16 21:12:35 +0000	[diff] [blame]	5471	The '<tt>llvm.cttz</tt>' family of intrinsic functions counts the number of
				5472	trailing zeros.
Chris Lattner	eff29ab	2005-05-15 19:39:26 +0000	[diff] [blame]	5473	</p>
				5474
				5475	<h5>Arguments:</h5>
				5476
				5477	<p>
				5478	The only argument is the value to be counted. The argument may be of any
Reid Spencer	a517338	2007-01-04 16:43:23 +0000	[diff] [blame]	5479	integer type. The return type must match the argument type.
Chris Lattner	eff29ab	2005-05-15 19:39:26 +0000	[diff] [blame]	5480	</p>
				5481
				5482	<h5>Semantics:</h5>
				5483
				5484	<p>
				5485	The '<tt>llvm.cttz</tt>' intrinsic counts the trailing (least significant) zeros
				5486	in a variable. If the src == 0 then the result is the size in bits of the type
				5487	of src. For example, <tt>llvm.cttz(2) = 1</tt>.
				5488	</p>
				5489	</div>
				5490
Reid Spencer	497d93e	2007-04-01 08:27:01 +0000	[diff] [blame]	5491	<!-- _______________________________________________________________________ -->
				5492	<div class="doc_subsubsection">
Reid Spencer	beacf66	2007-04-10 02:51:31 +0000	[diff] [blame]	5493	<a name="int_part_select">'<tt>llvm.part.select.*</tt>' Intrinsic</a>
Reid Spencer	a13ba7d	2007-04-01 19:00:37 +0000	[diff] [blame]	5494	</div>
				5495
				5496	<div class="doc_text">
				5497
				5498	<h5>Syntax:</h5>
Reid Spencer	beacf66	2007-04-10 02:51:31 +0000	[diff] [blame]	5499	<p>This is an overloaded intrinsic. You can use <tt>llvm.part.select</tt>
Reid Spencer	a13ba7d	2007-04-01 19:00:37 +0000	[diff] [blame]	5500	on any integer bit width.
				5501	<pre>
Chandler Carruth	6994040	2007-08-04 01:51:18 +0000	[diff] [blame]	5502	declare i17 @llvm.part.select.i17 (i17 %val, i32 %loBit, i32 %hiBit)
				5503	declare i29 @llvm.part.select.i29 (i29 %val, i32 %loBit, i32 %hiBit)
Reid Spencer	a13ba7d	2007-04-01 19:00:37 +0000	[diff] [blame]	5504	</pre>
				5505
				5506	<h5>Overview:</h5>
Reid Spencer	beacf66	2007-04-10 02:51:31 +0000	[diff] [blame]	5507	<p>The '<tt>llvm.part.select</tt>' family of intrinsic functions selects a
Reid Spencer	a13ba7d	2007-04-01 19:00:37 +0000	[diff] [blame]	5508	range of bits from an integer value and returns them in the same bit width as
				5509	the original value.</p>
				5510
				5511	<h5>Arguments:</h5>
				5512	<p>The first argument, <tt>%val</tt> and the result may be integer types of
				5513	any bit width but they must have the same bit width. The second and third
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	5514	arguments must be <tt>i32</tt> type since they specify only a bit index.</p>
Reid Spencer	a13ba7d	2007-04-01 19:00:37 +0000	[diff] [blame]	5515
				5516	<h5>Semantics:</h5>
Reid Spencer	beacf66	2007-04-10 02:51:31 +0000	[diff] [blame]	5517	<p>The operation of the '<tt>llvm.part.select</tt>' intrinsic has two modes
Reid Spencer	a3e435f	2007-04-04 02:42:35 +0000	[diff] [blame]	5518	of operation: forwards and reverse. If <tt>%loBit</tt> is greater than
				5519	<tt>%hiBits</tt> then the intrinsic operates in reverse mode. Otherwise it
				5520	operates in forward mode.</p>
				5521	<p>In forward mode, this intrinsic is the equivalent of shifting <tt>%val</tt>
				5522	right by <tt>%loBit</tt> bits and then ANDing it with a mask with
Reid Spencer	a13ba7d	2007-04-01 19:00:37 +0000	[diff] [blame]	5523	only the <tt>%hiBit - %loBit</tt> bits set, as follows:</p>
				5524	<ol>
				5525	<li>The <tt>%val</tt> is shifted right (LSHR) by the number of bits specified
				5526	by <tt>%loBits</tt>. This normalizes the value to the low order bits.</li>
				5527	<li>The <tt>%loBits</tt> value is subtracted from the <tt>%hiBits</tt> value
				5528	to determine the number of bits to retain.</li>
				5529	<li>A mask of the retained bits is created by shifting a -1 value.</li>
				5530	<li>The mask is ANDed with <tt>%val</tt> to produce the result.
				5531	</ol>
Reid Spencer	d6a85b5	2007-05-14 16:14:57 +0000	[diff] [blame]	5532	<p>In reverse mode, a similar computation is made except that the bits are
				5533	returned in the reverse order. So, for example, if <tt>X</tt> has the value
				5534	<tt>i16 0x0ACF (101011001111)</tt> and we apply
				5535	<tt>part.select(i16 X, 8, 3)</tt> to it, we get back the value
				5536	<tt>i16 0x0026 (000000100110)</tt>.</p>
Reid Spencer	a13ba7d	2007-04-01 19:00:37 +0000	[diff] [blame]	5537	</div>
				5538
Reid Spencer	f86037f	2007-04-11 23:23:49 +0000	[diff] [blame]	5539	<div class="doc_subsubsection">
				5540	<a name="int_part_set">'<tt>llvm.part.set.*</tt>' Intrinsic</a>
				5541	</div>
				5542
				5543	<div class="doc_text">
				5544
				5545	<h5>Syntax:</h5>
				5546	<p>This is an overloaded intrinsic. You can use <tt>llvm.part.set</tt>
				5547	on any integer bit width.
				5548	<pre>
Chandler Carruth	6994040	2007-08-04 01:51:18 +0000	[diff] [blame]	5549	declare i17 @llvm.part.set.i17.i9 (i17 %val, i9 %repl, i32 %lo, i32 %hi)
				5550	declare i29 @llvm.part.set.i29.i9 (i29 %val, i9 %repl, i32 %lo, i32 %hi)
Reid Spencer	f86037f	2007-04-11 23:23:49 +0000	[diff] [blame]	5551	</pre>
				5552
				5553	<h5>Overview:</h5>
				5554	<p>The '<tt>llvm.part.set</tt>' family of intrinsic functions replaces a range
				5555	of bits in an integer value with another integer value. It returns the integer
				5556	with the replaced bits.</p>
				5557
				5558	<h5>Arguments:</h5>
				5559	<p>The first argument, <tt>%val</tt> and the result may be integer types of
				5560	any bit width but they must have the same bit width. <tt>%val</tt> is the value
				5561	whose bits will be replaced. The second argument, <tt>%repl</tt> may be an
				5562	integer of any bit width. The third and fourth arguments must be <tt>i32</tt>
				5563	type since they specify only a bit index.</p>
				5564
				5565	<h5>Semantics:</h5>
				5566	<p>The operation of the '<tt>llvm.part.set</tt>' intrinsic has two modes
				5567	of operation: forwards and reverse. If <tt>%lo</tt> is greater than
				5568	<tt>%hi</tt> then the intrinsic operates in reverse mode. Otherwise it
				5569	operates in forward mode.</p>
				5570	<p>For both modes, the <tt>%repl</tt> value is prepared for use by either
				5571	truncating it down to the size of the replacement area or zero extending it
				5572	up to that size.</p>
				5573	<p>In forward mode, the bits between <tt>%lo</tt> and <tt>%hi</tt> (inclusive)
				5574	are replaced with corresponding bits from <tt>%repl</tt>. That is the 0th bit
				5575	in <tt>%repl</tt> replaces the <tt>%lo</tt>th bit in <tt>%val</tt> and etc. up
				5576	to the <tt>%hi</tt>th bit.
Reid Spencer	c6749c4	2007-05-14 16:50:20 +0000	[diff] [blame]	5577	<p>In reverse mode, a similar computation is made except that the bits are
				5578	reversed. That is, the <tt>0</tt>th bit in <tt>%repl</tt> replaces the
				5579	<tt>%hi</tt> bit in <tt>%val</tt> and etc. down to the <tt>%lo</tt>th bit.
Reid Spencer	f86037f	2007-04-11 23:23:49 +0000	[diff] [blame]	5580	<h5>Examples:</h5>
				5581	<pre>
Reid Spencer	f0dbf64	2007-04-12 01:03:03 +0000	[diff] [blame]	5582	llvm.part.set(0xFFFF, 0, 4, 7) -> 0xFF0F
Reid Spencer	c6749c4	2007-05-14 16:50:20 +0000	[diff] [blame]	5583	llvm.part.set(0xFFFF, 0, 7, 4) -> 0xFF0F
				5584	llvm.part.set(0xFFFF, 1, 7, 4) -> 0xFF8F
				5585	llvm.part.set(0xFFFF, F, 8, 3) -> 0xFFE7
Reid Spencer	f0dbf64	2007-04-12 01:03:03 +0000	[diff] [blame]	5586	llvm.part.set(0xFFFF, 0, 3, 8) -> 0xFE07
Reid Spencer	c891084	2007-04-11 23:49:50 +0000	[diff] [blame]	5587	</pre>
Reid Spencer	f86037f	2007-04-11 23:23:49 +0000	[diff] [blame]	5588	</div>
				5589
Chris Lattner	8ff7590	2004-01-06 05:31:32 +0000	[diff] [blame]	5590	<!-- ======================================================================= -->
				5591	<div class="doc_subsection">
				5592	<a name="int_debugger">Debugger Intrinsics</a>
				5593	</div>
				5594
				5595	<div class="doc_text">
				5596	<p>
				5597	The LLVM debugger intrinsics (which all start with <tt>llvm.dbg.</tt> prefix),
				5598	are described in the <a
				5599	href="SourceLevelDebugging.html#format_common_intrinsics">LLVM Source Level
				5600	Debugging</a> document.
				5601	</p>
				5602	</div>
				5603
				5604
Jim Laskey	dd4ef1b	2007-03-14 19:31:19 +0000	[diff] [blame]	5605	<!-- ======================================================================= -->
				5606	<div class="doc_subsection">
				5607	<a name="int_eh">Exception Handling Intrinsics</a>
				5608	</div>
				5609
				5610	<div class="doc_text">
				5611	<p> The LLVM exception handling intrinsics (which all start with
				5612	<tt>llvm.eh.</tt> prefix), are described in the <a
				5613	href="ExceptionHandling.html#format_common_intrinsics">LLVM Exception
				5614	Handling</a> document. </p>
				5615	</div>
				5616
Tanya Lattner	6d806e9	2007-06-15 20:50:54 +0000	[diff] [blame]	5617	<!-- ======================================================================= -->
				5618	<div class="doc_subsection">
Duncan Sands	f7331b3	2007-09-11 14:10:23 +0000	[diff] [blame]	5619	<a name="int_trampoline">Trampoline Intrinsic</a>
Duncan Sands	36397f5	2007-07-27 12:58:54 +0000	[diff] [blame]	5620	</div>
				5621
				5622	<div class="doc_text">
				5623	<p>
Duncan Sands	f7331b3	2007-09-11 14:10:23 +0000	[diff] [blame]	5624	This intrinsic makes it possible to excise one parameter, marked with
Duncan Sands	36397f5	2007-07-27 12:58:54 +0000	[diff] [blame]	5625	the <tt>nest</tt> attribute, from a function. The result is a callable
				5626	function pointer lacking the nest parameter - the caller does not need
				5627	to provide a value for it. Instead, the value to use is stored in
				5628	advance in a "trampoline", a block of memory usually allocated
				5629	on the stack, which also contains code to splice the nest value into the
				5630	argument list. This is used to implement the GCC nested function address
				5631	extension.
				5632	</p>
				5633	<p>
				5634	For example, if the function is
				5635	<tt>i32 f(i8* nest %c, i32 %x, i32 %y)</tt> then the resulting function
Bill Wendling	03295ca	2007-09-22 09:23:55 +0000	[diff] [blame]	5636	pointer has signature <tt>i32 (i32, i32)*</tt>. It can be created as follows:</p>
Duncan Sands	36397f5	2007-07-27 12:58:54 +0000	[diff] [blame]	5637	<pre>
Duncan Sands	f7331b3	2007-09-11 14:10:23 +0000	[diff] [blame]	5638	%tramp = alloca [10 x i8], align 4 ; size and alignment only correct for X86
				5639	%tramp1 = getelementptr [10 x i8]* %tramp, i32 0, i32 0
				5640	%p = call i8* @llvm.init.trampoline( i8* %tramp1, i8* bitcast (i32 (i8* nest , i32, i32)* @f to i8), i8 %nval )
				5641	%fp = bitcast i8* %p to i32 (i32, i32)*
Duncan Sands	36397f5	2007-07-27 12:58:54 +0000	[diff] [blame]	5642	</pre>
Bill Wendling	03295ca	2007-09-22 09:23:55 +0000	[diff] [blame]	5643	<p>The call <tt>%val = call i32 %fp( i32 %x, i32 %y )</tt> is then equivalent
				5644	to <tt>%val = call i32 %f( i8* %nval, i32 %x, i32 %y )</tt>.</p>
Duncan Sands	36397f5	2007-07-27 12:58:54 +0000	[diff] [blame]	5645	</div>
				5646
				5647	<!-- _______________________________________________________________________ -->
				5648	<div class="doc_subsubsection">
				5649	<a name="int_it">'<tt>llvm.init.trampoline</tt>' Intrinsic</a>
				5650	</div>
				5651	<div class="doc_text">
				5652	<h5>Syntax:</h5>
				5653	<pre>
Duncan Sands	f7331b3	2007-09-11 14:10:23 +0000	[diff] [blame]	5654	declare i8* @llvm.init.trampoline(i8* <tramp>, i8* <func>, i8* <nval>)
Duncan Sands	36397f5	2007-07-27 12:58:54 +0000	[diff] [blame]	5655	</pre>
				5656	<h5>Overview:</h5>
				5657	<p>
Duncan Sands	f7331b3	2007-09-11 14:10:23 +0000	[diff] [blame]	5658	This fills the memory pointed to by <tt>tramp</tt> with code
				5659	and returns a function pointer suitable for executing it.
Duncan Sands	36397f5	2007-07-27 12:58:54 +0000	[diff] [blame]	5660	</p>
				5661	<h5>Arguments:</h5>
				5662	<p>
				5663	The <tt>llvm.init.trampoline</tt> intrinsic takes three arguments, all
				5664	pointers. The <tt>tramp</tt> argument must point to a sufficiently large
				5665	and sufficiently aligned block of memory; this memory is written to by the
Duncan Sands	c00c2ba	2007-08-22 23:39:54 +0000	[diff] [blame]	5666	intrinsic. Note that the size and the alignment are target-specific - LLVM
				5667	currently provides no portable way of determining them, so a front-end that
				5668	generates this intrinsic needs to have some target-specific knowledge.
				5669	The <tt>func</tt> argument must hold a function bitcast to an <tt>i8*</tt>.
Duncan Sands	36397f5	2007-07-27 12:58:54 +0000	[diff] [blame]	5670	</p>
				5671	<h5>Semantics:</h5>
				5672	<p>
				5673	The block of memory pointed to by <tt>tramp</tt> is filled with target
Duncan Sands	f7331b3	2007-09-11 14:10:23 +0000	[diff] [blame]	5674	dependent code, turning it into a function. A pointer to this function is
				5675	returned, but needs to be bitcast to an
Duncan Sands	36397f5	2007-07-27 12:58:54 +0000	[diff] [blame]	5676	<a href="#int_trampoline">appropriate function pointer type</a>
Duncan Sands	f7331b3	2007-09-11 14:10:23 +0000	[diff] [blame]	5677	before being called. The new function's signature is the same as that of
				5678	<tt>func</tt> with any arguments marked with the <tt>nest</tt> attribute
				5679	removed. At most one such <tt>nest</tt> argument is allowed, and it must be
				5680	of pointer type. Calling the new function is equivalent to calling
				5681	<tt>func</tt> with the same argument list, but with <tt>nval</tt> used for the
				5682	missing <tt>nest</tt> argument. If, after calling
				5683	<tt>llvm.init.trampoline</tt>, the memory pointed to by <tt>tramp</tt> is
				5684	modified, then the effect of any later call to the returned function pointer is
				5685	undefined.
Duncan Sands	36397f5	2007-07-27 12:58:54 +0000	[diff] [blame]	5686	</p>
				5687	</div>
				5688
				5689	<!-- ======================================================================= -->
				5690	<div class="doc_subsection">
Andrew Lenharth	22c5c1b	2008-02-16 01:24:58 +0000	[diff] [blame]	5691	<a name="int_atomics">Atomic Operations and Synchronization Intrinsics</a>
				5692	</div>
				5693
				5694	<div class="doc_text">
				5695	<p>
				5696	These intrinsic functions expand the "universal IR" of LLVM to represent
				5697	hardware constructs for atomic operations and memory synchronization. This
				5698	provides an interface to the hardware, not an interface to the programmer. It
Chris Lattner	d3eda89	2008-08-05 18:29:16 +0000	[diff] [blame]	5699	is aimed at a low enough level to allow any programming models or APIs
				5700	(Application Programming Interfaces) which
Andrew Lenharth	22c5c1b	2008-02-16 01:24:58 +0000	[diff] [blame]	5701	need atomic behaviors to map cleanly onto it. It is also modeled primarily on
				5702	hardware behavior. Just as hardware provides a "universal IR" for source
				5703	languages, it also provides a starting point for developing a "universal"
				5704	atomic operation and synchronization IR.
				5705	</p>
				5706	<p>
				5707	These do <em>not</em> form an API such as high-level threading libraries,
				5708	software transaction memory systems, atomic primitives, and intrinsic
				5709	functions as found in BSD, GNU libc, atomic_ops, APR, and other system and
				5710	application libraries. The hardware interface provided by LLVM should allow
				5711	a clean implementation of all of these APIs and parallel programming models.
				5712	No one model or paradigm should be selected above others unless the hardware
				5713	itself ubiquitously does so.
				5714
				5715	</p>
				5716	</div>
				5717
				5718	<!-- _______________________________________________________________________ -->
				5719	<div class="doc_subsubsection">
				5720	<a name="int_memory_barrier">'<tt>llvm.memory.barrier</tt>' Intrinsic</a>
				5721	</div>
				5722	<div class="doc_text">
				5723	<h5>Syntax:</h5>
				5724	<pre>
				5725	declare void @llvm.memory.barrier( i1 <ll>, i1 <ls>, i1 <sl>, i1 <ss>,
				5726	i1 <device> )
				5727
				5728	</pre>
				5729	<h5>Overview:</h5>
				5730	<p>
				5731	The <tt>llvm.memory.barrier</tt> intrinsic guarantees ordering between
				5732	specific pairs of memory access types.
				5733	</p>
				5734	<h5>Arguments:</h5>
				5735	<p>
				5736	The <tt>llvm.memory.barrier</tt> intrinsic requires five boolean arguments.
				5737	The first four arguments enables a specific barrier as listed below. The fith
				5738	argument specifies that the barrier applies to io or device or uncached memory.
				5739
				5740	</p>
				5741	<ul>
				5742	<li><tt>ll</tt>: load-load barrier</li>
				5743	<li><tt>ls</tt>: load-store barrier</li>
				5744	<li><tt>sl</tt>: store-load barrier</li>
				5745	<li><tt>ss</tt>: store-store barrier</li>
				5746	<li><tt>device</tt>: barrier applies to device and uncached memory also.
				5747	</ul>
				5748	<h5>Semantics:</h5>
				5749	<p>
				5750	This intrinsic causes the system to enforce some ordering constraints upon
				5751	the loads and stores of the program. This barrier does not indicate
				5752	<em>when</em> any events will occur, it only enforces an <em>order</em> in
				5753	which they occur. For any of the specified pairs of load and store operations
				5754	(f.ex. load-load, or store-load), all of the first operations preceding the
				5755	barrier will complete before any of the second operations succeeding the
				5756	barrier begin. Specifically the semantics for each pairing is as follows:
				5757	</p>
				5758	<ul>
				5759	<li><tt>ll</tt>: All loads before the barrier must complete before any load
				5760	after the barrier begins.</li>
				5761
				5762	<li><tt>ls</tt>: All loads before the barrier must complete before any
				5763	store after the barrier begins.</li>
				5764	<li><tt>ss</tt>: All stores before the barrier must complete before any
				5765	store after the barrier begins.</li>
				5766	<li><tt>sl</tt>: All stores before the barrier must complete before any
				5767	load after the barrier begins.</li>
				5768	</ul>
				5769	<p>
				5770	These semantics are applied with a logical "and" behavior when more than one
				5771	is enabled in a single memory barrier intrinsic.
				5772	</p>
				5773	<p>
				5774	Backends may implement stronger barriers than those requested when they do not
				5775	support as fine grained a barrier as requested. Some architectures do not
				5776	need all types of barriers and on such architectures, these become noops.
				5777	</p>
				5778	<h5>Example:</h5>
				5779	<pre>
				5780	%ptr = malloc i32
				5781	store i32 4, %ptr
				5782
				5783	%result1 = load i32* %ptr <i>; yields {i32}:result1 = 4</i>
				5784	call void @llvm.memory.barrier( i1 false, i1 true, i1 false, i1 false )
				5785	<i>; guarantee the above finishes</i>
				5786	store i32 8, %ptr <i>; before this begins</i>
				5787	</pre>
				5788	</div>
				5789
Andrew Lenharth	ab0b949	2008-02-21 06:45:13 +0000	[diff] [blame]	5790	<!-- _______________________________________________________________________ -->
				5791	<div class="doc_subsubsection">
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	5792	<a name="int_atomic_cmp_swap">'<tt>llvm.atomic.cmp.swap.*</tt>' Intrinsic</a>
Andrew Lenharth	ab0b949	2008-02-21 06:45:13 +0000	[diff] [blame]	5793	</div>
				5794	<div class="doc_text">
				5795	<h5>Syntax:</h5>
				5796	<p>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	5797	This is an overloaded intrinsic. You can use <tt>llvm.atomic.cmp.swap</tt> on
				5798	any integer bit width and for different address spaces. Not all targets
				5799	support all bit widths however.</p>
Andrew Lenharth	ab0b949	2008-02-21 06:45:13 +0000	[diff] [blame]	5800
				5801	<pre>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	5802	declare i8 @llvm.atomic.cmp.swap.i8.p0i8( i8* <ptr>, i8 <cmp>, i8 <val> )
				5803	declare i16 @llvm.atomic.cmp.swap.i16.p0i16( i16* <ptr>, i16 <cmp>, i16 <val> )
				5804	declare i32 @llvm.atomic.cmp.swap.i32.p0i32( i32* <ptr>, i32 <cmp>, i32 <val> )
				5805	declare i64 @llvm.atomic.cmp.swap.i64.p0i64( i64* <ptr>, i64 <cmp>, i64 <val> )
Andrew Lenharth	ab0b949	2008-02-21 06:45:13 +0000	[diff] [blame]	5806
				5807	</pre>
				5808	<h5>Overview:</h5>
				5809	<p>
				5810	This loads a value in memory and compares it to a given value. If they are
				5811	equal, it stores a new value into the memory.
				5812	</p>
				5813	<h5>Arguments:</h5>
				5814	<p>
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	5815	The <tt>llvm.atomic.cmp.swap</tt> intrinsic takes three arguments. The result as
Andrew Lenharth	ab0b949	2008-02-21 06:45:13 +0000	[diff] [blame]	5816	well as both <tt>cmp</tt> and <tt>val</tt> must be integer values with the
				5817	same bit width. The <tt>ptr</tt> argument must be a pointer to a value of
				5818	this integer type. While any bit width integer may be used, targets may only
				5819	lower representations they support in hardware.
				5820
				5821	</p>
				5822	<h5>Semantics:</h5>
				5823	<p>
				5824	This entire intrinsic must be executed atomically. It first loads the value
				5825	in memory pointed to by <tt>ptr</tt> and compares it with the value
				5826	<tt>cmp</tt>. If they are equal, <tt>val</tt> is stored into the memory. The
				5827	loaded value is yielded in all cases. This provides the equivalent of an
				5828	atomic compare-and-swap operation within the SSA framework.
				5829	</p>
				5830	<h5>Examples:</h5>
				5831
				5832	<pre>
				5833	%ptr = malloc i32
				5834	store i32 4, %ptr
				5835
				5836	%val1 = add i32 4, 4
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	5837	%result1 = call i32 @llvm.atomic.cmp.swap.i32.p0i32( i32* %ptr, i32 4, %val1 )
Andrew Lenharth	ab0b949	2008-02-21 06:45:13 +0000	[diff] [blame]	5838	<i>; yields {i32}:result1 = 4</i>
				5839	%stored1 = icmp eq i32 %result1, 4 <i>; yields {i1}:stored1 = true</i>
				5840	%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = 8</i>
				5841
				5842	%val2 = add i32 1, 1
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	5843	%result2 = call i32 @llvm.atomic.cmp.swap.i32.p0i32( i32* %ptr, i32 5, %val2 )
Andrew Lenharth	ab0b949	2008-02-21 06:45:13 +0000	[diff] [blame]	5844	<i>; yields {i32}:result2 = 8</i>
				5845	%stored2 = icmp eq i32 %result2, 5 <i>; yields {i1}:stored2 = false</i>
				5846
				5847	%memval2 = load i32* %ptr <i>; yields {i32}:memval2 = 8</i>
				5848	</pre>
				5849	</div>
				5850
				5851	<!-- _______________________________________________________________________ -->
				5852	<div class="doc_subsubsection">
				5853	<a name="int_atomic_swap">'<tt>llvm.atomic.swap.*</tt>' Intrinsic</a>
				5854	</div>
				5855	<div class="doc_text">
				5856	<h5>Syntax:</h5>
				5857
				5858	<p>
				5859	This is an overloaded intrinsic. You can use <tt>llvm.atomic.swap</tt> on any
				5860	integer bit width. Not all targets support all bit widths however.</p>
				5861	<pre>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	5862	declare i8 @llvm.atomic.swap.i8.p0i8( i8* <ptr>, i8 <val> )
				5863	declare i16 @llvm.atomic.swap.i16.p0i16( i16* <ptr>, i16 <val> )
				5864	declare i32 @llvm.atomic.swap.i32.p0i32( i32* <ptr>, i32 <val> )
				5865	declare i64 @llvm.atomic.swap.i64.p0i64( i64* <ptr>, i64 <val> )
Andrew Lenharth	ab0b949	2008-02-21 06:45:13 +0000	[diff] [blame]	5866
				5867	</pre>
				5868	<h5>Overview:</h5>
				5869	<p>
				5870	This intrinsic loads the value stored in memory at <tt>ptr</tt> and yields
				5871	the value from memory. It then stores the value in <tt>val</tt> in the memory
				5872	at <tt>ptr</tt>.
				5873	</p>
				5874	<h5>Arguments:</h5>
				5875
				5876	<p>
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	5877	The <tt>llvm.atomic.swap</tt> intrinsic takes two arguments. Both the
Andrew Lenharth	ab0b949	2008-02-21 06:45:13 +0000	[diff] [blame]	5878	<tt>val</tt> argument and the result must be integers of the same bit width.
				5879	The first argument, <tt>ptr</tt>, must be a pointer to a value of this
				5880	integer type. The targets may only lower integer representations they
				5881	support.
				5882	</p>
				5883	<h5>Semantics:</h5>
				5884	<p>
				5885	This intrinsic loads the value pointed to by <tt>ptr</tt>, yields it, and
				5886	stores <tt>val</tt> back into <tt>ptr</tt> atomically. This provides the
				5887	equivalent of an atomic swap operation within the SSA framework.
				5888
				5889	</p>
				5890	<h5>Examples:</h5>
				5891	<pre>
				5892	%ptr = malloc i32
				5893	store i32 4, %ptr
				5894
				5895	%val1 = add i32 4, 4
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	5896	%result1 = call i32 @llvm.atomic.swap.i32.p0i32( i32* %ptr, i32 %val1 )
Andrew Lenharth	ab0b949	2008-02-21 06:45:13 +0000	[diff] [blame]	5897	<i>; yields {i32}:result1 = 4</i>
				5898	%stored1 = icmp eq i32 %result1, 4 <i>; yields {i1}:stored1 = true</i>
				5899	%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = 8</i>
				5900
				5901	%val2 = add i32 1, 1
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	5902	%result2 = call i32 @llvm.atomic.swap.i32.p0i32( i32* %ptr, i32 %val2 )
Andrew Lenharth	ab0b949	2008-02-21 06:45:13 +0000	[diff] [blame]	5903	<i>; yields {i32}:result2 = 8</i>
				5904
				5905	%stored2 = icmp eq i32 %result2, 8 <i>; yields {i1}:stored2 = true</i>
				5906	%memval2 = load i32* %ptr <i>; yields {i32}:memval2 = 2</i>
				5907	</pre>
				5908	</div>
				5909
				5910	<!-- _______________________________________________________________________ -->
				5911	<div class="doc_subsubsection">
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	5912	<a name="int_atomic_load_add">'<tt>llvm.atomic.load.add.*</tt>' Intrinsic</a>
Andrew Lenharth	ab0b949	2008-02-21 06:45:13 +0000	[diff] [blame]	5913
				5914	</div>
				5915	<div class="doc_text">
				5916	<h5>Syntax:</h5>
				5917	<p>
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	5918	This is an overloaded intrinsic. You can use <tt>llvm.atomic.load.add</tt> on any
Andrew Lenharth	ab0b949	2008-02-21 06:45:13 +0000	[diff] [blame]	5919	integer bit width. Not all targets support all bit widths however.</p>
				5920	<pre>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	5921	declare i8 @llvm.atomic.load.add.i8..p0i8( i8* <ptr>, i8 <delta> )
				5922	declare i16 @llvm.atomic.load.add.i16..p0i16( i16* <ptr>, i16 <delta> )
				5923	declare i32 @llvm.atomic.load.add.i32..p0i32( i32* <ptr>, i32 <delta> )
				5924	declare i64 @llvm.atomic.load.add.i64..p0i64( i64* <ptr>, i64 <delta> )
Andrew Lenharth	ab0b949	2008-02-21 06:45:13 +0000	[diff] [blame]	5925
				5926	</pre>
				5927	<h5>Overview:</h5>
				5928	<p>
				5929	This intrinsic adds <tt>delta</tt> to the value stored in memory at
				5930	<tt>ptr</tt>. It yields the original value at <tt>ptr</tt>.
				5931	</p>
				5932	<h5>Arguments:</h5>
				5933	<p>
				5934
				5935	The intrinsic takes two arguments, the first a pointer to an integer value
				5936	and the second an integer value. The result is also an integer value. These
				5937	integer types can have any bit width, but they must all have the same bit
				5938	width. The targets may only lower integer representations they support.
				5939	</p>
				5940	<h5>Semantics:</h5>
				5941	<p>
				5942	This intrinsic does a series of operations atomically. It first loads the
				5943	value stored at <tt>ptr</tt>. It then adds <tt>delta</tt>, stores the result
				5944	to <tt>ptr</tt>. It yields the original value stored at <tt>ptr</tt>.
				5945	</p>
				5946
				5947	<h5>Examples:</h5>
				5948	<pre>
				5949	%ptr = malloc i32
				5950	store i32 4, %ptr
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	5951	%result1 = call i32 @llvm.atomic.load.add.i32.p0i32( i32* %ptr, i32 4 )
Andrew Lenharth	ab0b949	2008-02-21 06:45:13 +0000	[diff] [blame]	5952	<i>; yields {i32}:result1 = 4</i>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	5953	%result2 = call i32 @llvm.atomic.load.add.i32.p0i32( i32* %ptr, i32 2 )
Andrew Lenharth	ab0b949	2008-02-21 06:45:13 +0000	[diff] [blame]	5954	<i>; yields {i32}:result2 = 8</i>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	5955	%result3 = call i32 @llvm.atomic.load.add.i32.p0i32( i32* %ptr, i32 5 )
Andrew Lenharth	ab0b949	2008-02-21 06:45:13 +0000	[diff] [blame]	5956	<i>; yields {i32}:result3 = 10</i>
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	5957	%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = 15</i>
Andrew Lenharth	ab0b949	2008-02-21 06:45:13 +0000	[diff] [blame]	5958	</pre>
				5959	</div>
				5960
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	5961	<!-- _______________________________________________________________________ -->
				5962	<div class="doc_subsubsection">
				5963	<a name="int_atomic_load_sub">'<tt>llvm.atomic.load.sub.*</tt>' Intrinsic</a>
				5964
				5965	</div>
				5966	<div class="doc_text">
				5967	<h5>Syntax:</h5>
				5968	<p>
				5969	This is an overloaded intrinsic. You can use <tt>llvm.atomic.load.sub</tt> on
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	5970	any integer bit width and for different address spaces. Not all targets
				5971	support all bit widths however.</p>
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	5972	<pre>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	5973	declare i8 @llvm.atomic.load.sub.i8.p0i32( i8* <ptr>, i8 <delta> )
				5974	declare i16 @llvm.atomic.load.sub.i16.p0i32( i16* <ptr>, i16 <delta> )
				5975	declare i32 @llvm.atomic.load.sub.i32.p0i32( i32* <ptr>, i32 <delta> )
				5976	declare i64 @llvm.atomic.load.sub.i64.p0i32( i64* <ptr>, i64 <delta> )
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	5977
				5978	</pre>
				5979	<h5>Overview:</h5>
				5980	<p>
				5981	This intrinsic subtracts <tt>delta</tt> to the value stored in memory at
				5982	<tt>ptr</tt>. It yields the original value at <tt>ptr</tt>.
				5983	</p>
				5984	<h5>Arguments:</h5>
				5985	<p>
				5986
				5987	The intrinsic takes two arguments, the first a pointer to an integer value
				5988	and the second an integer value. The result is also an integer value. These
				5989	integer types can have any bit width, but they must all have the same bit
				5990	width. The targets may only lower integer representations they support.
				5991	</p>
				5992	<h5>Semantics:</h5>
				5993	<p>
				5994	This intrinsic does a series of operations atomically. It first loads the
				5995	value stored at <tt>ptr</tt>. It then subtracts <tt>delta</tt>, stores the
				5996	result to <tt>ptr</tt>. It yields the original value stored at <tt>ptr</tt>.
				5997	</p>
				5998
				5999	<h5>Examples:</h5>
				6000	<pre>
				6001	%ptr = malloc i32
				6002	store i32 8, %ptr
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	6003	%result1 = call i32 @llvm.atomic.load.sub.i32.p0i32( i32* %ptr, i32 4 )
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	6004	<i>; yields {i32}:result1 = 8</i>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	6005	%result2 = call i32 @llvm.atomic.load.sub.i32.p0i32( i32* %ptr, i32 2 )
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	6006	<i>; yields {i32}:result2 = 4</i>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	6007	%result3 = call i32 @llvm.atomic.load.sub.i32.p0i32( i32* %ptr, i32 5 )
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	6008	<i>; yields {i32}:result3 = 2</i>
				6009	%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = -3</i>
				6010	</pre>
				6011	</div>
				6012
				6013	<!-- _______________________________________________________________________ -->
				6014	<div class="doc_subsubsection">
				6015	<a name="int_atomic_load_and">'<tt>llvm.atomic.load.and.*</tt>' Intrinsic</a><br>
				6016	<a name="int_atomic_load_nand">'<tt>llvm.atomic.load.nand.*</tt>' Intrinsic</a><br>
				6017	<a name="int_atomic_load_or">'<tt>llvm.atomic.load.or.*</tt>' Intrinsic</a><br>
				6018	<a name="int_atomic_load_xor">'<tt>llvm.atomic.load.xor.*</tt>' Intrinsic</a><br>
				6019
				6020	</div>
				6021	<div class="doc_text">
				6022	<h5>Syntax:</h5>
				6023	<p>
				6024	These are overloaded intrinsics. You can use <tt>llvm.atomic.load_and</tt>,
				6025	<tt>llvm.atomic.load_nand</tt>, <tt>llvm.atomic.load_or</tt>, and
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	6026	<tt>llvm.atomic.load_xor</tt> on any integer bit width and for different
				6027	address spaces. Not all targets support all bit widths however.</p>
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	6028	<pre>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	6029	declare i8 @llvm.atomic.load.and.i8.p0i8( i8* <ptr>, i8 <delta> )
				6030	declare i16 @llvm.atomic.load.and.i16.p0i16( i16* <ptr>, i16 <delta> )
				6031	declare i32 @llvm.atomic.load.and.i32.p0i32( i32* <ptr>, i32 <delta> )
				6032	declare i64 @llvm.atomic.load.and.i64.p0i64( i64* <ptr>, i64 <delta> )
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	6033
				6034	</pre>
				6035
				6036	<pre>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	6037	declare i8 @llvm.atomic.load.or.i8.p0i8( i8* <ptr>, i8 <delta> )
				6038	declare i16 @llvm.atomic.load.or.i16.p0i16( i16* <ptr>, i16 <delta> )
				6039	declare i32 @llvm.atomic.load.or.i32.p0i32( i32* <ptr>, i32 <delta> )
				6040	declare i64 @llvm.atomic.load.or.i64.p0i64( i64* <ptr>, i64 <delta> )
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	6041
				6042	</pre>
				6043
				6044	<pre>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	6045	declare i8 @llvm.atomic.load.nand.i8.p0i32( i8* <ptr>, i8 <delta> )
				6046	declare i16 @llvm.atomic.load.nand.i16.p0i32( i16* <ptr>, i16 <delta> )
				6047	declare i32 @llvm.atomic.load.nand.i32.p0i32( i32* <ptr>, i32 <delta> )
				6048	declare i64 @llvm.atomic.load.nand.i64.p0i32( i64* <ptr>, i64 <delta> )
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	6049
				6050	</pre>
				6051
				6052	<pre>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	6053	declare i8 @llvm.atomic.load.xor.i8.p0i32( i8* <ptr>, i8 <delta> )
				6054	declare i16 @llvm.atomic.load.xor.i16.p0i32( i16* <ptr>, i16 <delta> )
				6055	declare i32 @llvm.atomic.load.xor.i32.p0i32( i32* <ptr>, i32 <delta> )
				6056	declare i64 @llvm.atomic.load.xor.i64.p0i32( i64* <ptr>, i64 <delta> )
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	6057
				6058	</pre>
				6059	<h5>Overview:</h5>
				6060	<p>
				6061	These intrinsics bitwise the operation (and, nand, or, xor) <tt>delta</tt> to
				6062	the value stored in memory at <tt>ptr</tt>. It yields the original value
				6063	at <tt>ptr</tt>.
				6064	</p>
				6065	<h5>Arguments:</h5>
				6066	<p>
				6067
				6068	These intrinsics take two arguments, the first a pointer to an integer value
				6069	and the second an integer value. The result is also an integer value. These
				6070	integer types can have any bit width, but they must all have the same bit
				6071	width. The targets may only lower integer representations they support.
				6072	</p>
				6073	<h5>Semantics:</h5>
				6074	<p>
				6075	These intrinsics does a series of operations atomically. They first load the
				6076	value stored at <tt>ptr</tt>. They then do the bitwise operation
				6077	<tt>delta</tt>, store the result to <tt>ptr</tt>. They yield the original
				6078	value stored at <tt>ptr</tt>.
				6079	</p>
				6080
				6081	<h5>Examples:</h5>
				6082	<pre>
				6083	%ptr = malloc i32
				6084	store i32 0x0F0F, %ptr
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	6085	%result0 = call i32 @llvm.atomic.load.nand.i32.p0i32( i32* %ptr, i32 0xFF )
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	6086	<i>; yields {i32}:result0 = 0x0F0F</i>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	6087	%result1 = call i32 @llvm.atomic.load.and.i32.p0i32( i32* %ptr, i32 0xFF )
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	6088	<i>; yields {i32}:result1 = 0xFFFFFFF0</i>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	6089	%result2 = call i32 @llvm.atomic.load.or.i32.p0i32( i32* %ptr, i32 0F )
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	6090	<i>; yields {i32}:result2 = 0xF0</i>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	6091	%result3 = call i32 @llvm.atomic.load.xor.i32.p0i32( i32* %ptr, i32 0F )
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	6092	<i>; yields {i32}:result3 = FF</i>
				6093	%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = F0</i>
				6094	</pre>
				6095	</div>
				6096
				6097
				6098	<!-- _______________________________________________________________________ -->
				6099	<div class="doc_subsubsection">
				6100	<a name="int_atomic_load_max">'<tt>llvm.atomic.load.max.*</tt>' Intrinsic</a><br>
				6101	<a name="int_atomic_load_min">'<tt>llvm.atomic.load.min.*</tt>' Intrinsic</a><br>
				6102	<a name="int_atomic_load_umax">'<tt>llvm.atomic.load.umax.*</tt>' Intrinsic</a><br>
				6103	<a name="int_atomic_load_umin">'<tt>llvm.atomic.load.umin.*</tt>' Intrinsic</a><br>
				6104
				6105	</div>
				6106	<div class="doc_text">
				6107	<h5>Syntax:</h5>
				6108	<p>
				6109	These are overloaded intrinsics. You can use <tt>llvm.atomic.load_max</tt>,
				6110	<tt>llvm.atomic.load_min</tt>, <tt>llvm.atomic.load_umax</tt>, and
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	6111	<tt>llvm.atomic.load_umin</tt> on any integer bit width and for different
				6112	address spaces. Not all targets
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	6113	support all bit widths however.</p>
				6114	<pre>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	6115	declare i8 @llvm.atomic.load.max.i8.p0i8( i8* <ptr>, i8 <delta> )
				6116	declare i16 @llvm.atomic.load.max.i16.p0i16( i16* <ptr>, i16 <delta> )
				6117	declare i32 @llvm.atomic.load.max.i32.p0i32( i32* <ptr>, i32 <delta> )
				6118	declare i64 @llvm.atomic.load.max.i64.p0i64( i64* <ptr>, i64 <delta> )
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	6119
				6120	</pre>
				6121
				6122	<pre>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	6123	declare i8 @llvm.atomic.load.min.i8.p0i8( i8* <ptr>, i8 <delta> )
				6124	declare i16 @llvm.atomic.load.min.i16.p0i16( i16* <ptr>, i16 <delta> )
				6125	declare i32 @llvm.atomic.load.min.i32..p0i32( i32* <ptr>, i32 <delta> )
				6126	declare i64 @llvm.atomic.load.min.i64..p0i64( i64* <ptr>, i64 <delta> )
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	6127
				6128	</pre>
				6129
				6130	<pre>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	6131	declare i8 @llvm.atomic.load.umax.i8.p0i8( i8* <ptr>, i8 <delta> )
				6132	declare i16 @llvm.atomic.load.umax.i16.p0i16( i16* <ptr>, i16 <delta> )
				6133	declare i32 @llvm.atomic.load.umax.i32.p0i32( i32* <ptr>, i32 <delta> )
				6134	declare i64 @llvm.atomic.load.umax.i64.p0i64( i64* <ptr>, i64 <delta> )
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	6135
				6136	</pre>
				6137
				6138	<pre>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	6139	declare i8 @llvm.atomic.load.umin.i8..p0i8( i8* <ptr>, i8 <delta> )
				6140	declare i16 @llvm.atomic.load.umin.i16.p0i16( i16* <ptr>, i16 <delta> )
				6141	declare i32 @llvm.atomic.load.umin.i32..p0i32( i32* <ptr>, i32 <delta> )
				6142	declare i64 @llvm.atomic.load.umin.i64..p0i64( i64* <ptr>, i64 <delta> )
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	6143
				6144	</pre>
				6145	<h5>Overview:</h5>
				6146	<p>
				6147	These intrinsics takes the signed or unsigned minimum or maximum of
				6148	<tt>delta</tt> and the value stored in memory at <tt>ptr</tt>. It yields the
				6149	original value at <tt>ptr</tt>.
				6150	</p>
				6151	<h5>Arguments:</h5>
				6152	<p>
				6153
				6154	These intrinsics take two arguments, the first a pointer to an integer value
				6155	and the second an integer value. The result is also an integer value. These
				6156	integer types can have any bit width, but they must all have the same bit
				6157	width. The targets may only lower integer representations they support.
				6158	</p>
				6159	<h5>Semantics:</h5>
				6160	<p>
				6161	These intrinsics does a series of operations atomically. They first load the
				6162	value stored at <tt>ptr</tt>. They then do the signed or unsigned min or max
				6163	<tt>delta</tt> and the value, store the result to <tt>ptr</tt>. They yield
				6164	the original value stored at <tt>ptr</tt>.
				6165	</p>
				6166
				6167	<h5>Examples:</h5>
				6168	<pre>
				6169	%ptr = malloc i32
				6170	store i32 7, %ptr
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	6171	%result0 = call i32 @llvm.atomic.load.min.i32.p0i32( i32* %ptr, i32 -2 )
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	6172	<i>; yields {i32}:result0 = 7</i>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	6173	%result1 = call i32 @llvm.atomic.load.max.i32.p0i32( i32* %ptr, i32 8 )
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	6174	<i>; yields {i32}:result1 = -2</i>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	6175	%result2 = call i32 @llvm.atomic.load.umin.i32.p0i32( i32* %ptr, i32 10 )
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	6176	<i>; yields {i32}:result2 = 8</i>
Mon P Wang	e3b3a72	2008-07-30 04:36:53 +0000	[diff] [blame]	6177	%result3 = call i32 @llvm.atomic.load.umax.i32.p0i32( i32* %ptr, i32 30 )
Mon P Wang	2887310	2008-06-25 08:15:39 +0000	[diff] [blame]	6178	<i>; yields {i32}:result3 = 8</i>
				6179	%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = 30</i>
				6180	</pre>
				6181	</div>
Andrew Lenharth	22c5c1b	2008-02-16 01:24:58 +0000	[diff] [blame]	6182
				6183	<!-- ======================================================================= -->
				6184	<div class="doc_subsection">
Tanya Lattner	6d806e9	2007-06-15 20:50:54 +0000	[diff] [blame]	6185	<a name="int_general">General Intrinsics</a>
				6186	</div>
				6187
				6188	<div class="doc_text">
				6189	<p> This class of intrinsics is designed to be generic and has
				6190	no specific purpose. </p>
				6191	</div>
				6192
				6193	<!-- _______________________________________________________________________ -->
				6194	<div class="doc_subsubsection">
				6195	<a name="int_var_annotation">'<tt>llvm.var.annotation</tt>' Intrinsic</a>
				6196	</div>
				6197
				6198	<div class="doc_text">
				6199
				6200	<h5>Syntax:</h5>
				6201	<pre>
Tanya Lattner	d2e8442	2007-06-18 23:42:37 +0000	[diff] [blame]	6202	declare void @llvm.var.annotation(i8* <val>, i8* <str>, i8* <str>, i32 <int> )
Tanya Lattner	6d806e9	2007-06-15 20:50:54 +0000	[diff] [blame]	6203	</pre>
				6204
				6205	<h5>Overview:</h5>
				6206
				6207	<p>
				6208	The '<tt>llvm.var.annotation</tt>' intrinsic
				6209	</p>
				6210
				6211	<h5>Arguments:</h5>
				6212
				6213	<p>
Tanya Lattner	d2e8442	2007-06-18 23:42:37 +0000	[diff] [blame]	6214	The first argument is a pointer to a value, the second is a pointer to a
				6215	global string, the third is a pointer to a global string which is the source
				6216	file name, and the last argument is the line number.
Tanya Lattner	6d806e9	2007-06-15 20:50:54 +0000	[diff] [blame]	6217	</p>
				6218
				6219	<h5>Semantics:</h5>
				6220
				6221	<p>
Anton Korobeynikov	4cb8618	2008-01-15 22:31:34 +0000	[diff] [blame]	6222	This intrinsic allows annotation of local variables with arbitrary strings.
Tanya Lattner	6d806e9	2007-06-15 20:50:54 +0000	[diff] [blame]	6223	This can be useful for special purpose optimizations that want to look for these
Anton Korobeynikov	4cb8618	2008-01-15 22:31:34 +0000	[diff] [blame]	6224	annotations. These have no other defined use, they are ignored by code
				6225	generation and optimization.
				6226	</p>
Tanya Lattner	6d806e9	2007-06-15 20:50:54 +0000	[diff] [blame]	6227	</div>
				6228
Tanya Lattner	b636788	2007-09-21 22:59:12 +0000	[diff] [blame]	6229	<!-- _______________________________________________________________________ -->
				6230	<div class="doc_subsubsection">
Tanya Lattner	e1a8da0	2007-09-21 23:57:59 +0000	[diff] [blame]	6231	<a name="int_annotation">'<tt>llvm.annotation.*</tt>' Intrinsic</a>
Tanya Lattner	b636788	2007-09-21 22:59:12 +0000	[diff] [blame]	6232	</div>
				6233
				6234	<div class="doc_text">
				6235
				6236	<h5>Syntax:</h5>
Tanya Lattner	39cfba6	2007-09-21 23:56:27 +0000	[diff] [blame]	6237	<p>This is an overloaded intrinsic. You can use '<tt>llvm.annotation</tt>' on
				6238	any integer bit width.
				6239	</p>
Tanya Lattner	b636788	2007-09-21 22:59:12 +0000	[diff] [blame]	6240	<pre>
Tanya Lattner	d3989a8	2007-09-22 00:03:01 +0000	[diff] [blame]	6241	declare i8 @llvm.annotation.i8(i8 <val>, i8* <str>, i8* <str>, i32 <int> )
				6242	declare i16 @llvm.annotation.i16(i16 <val>, i8* <str>, i8* <str>, i32 <int> )
				6243	declare i32 @llvm.annotation.i32(i32 <val>, i8* <str>, i8* <str>, i32 <int> )
				6244	declare i64 @llvm.annotation.i64(i64 <val>, i8* <str>, i8* <str>, i32 <int> )
				6245	declare i256 @llvm.annotation.i256(i256 <val>, i8* <str>, i8* <str>, i32 <int> )
Tanya Lattner	b636788	2007-09-21 22:59:12 +0000	[diff] [blame]	6246	</pre>
				6247
				6248	<h5>Overview:</h5>
Tanya Lattner	39cfba6	2007-09-21 23:56:27 +0000	[diff] [blame]	6249
				6250	<p>
				6251	The '<tt>llvm.annotation</tt>' intrinsic.
Tanya Lattner	b636788	2007-09-21 22:59:12 +0000	[diff] [blame]	6252	</p>
				6253
				6254	<h5>Arguments:</h5>
				6255
				6256	<p>
				6257	The first argument is an integer value (result of some expression),
				6258	the second is a pointer to a global string, the third is a pointer to a global
				6259	string which is the source file name, and the last argument is the line number.
Tanya Lattner	39cfba6	2007-09-21 23:56:27 +0000	[diff] [blame]	6260	It returns the value of the first argument.
Tanya Lattner	b636788	2007-09-21 22:59:12 +0000	[diff] [blame]	6261	</p>
				6262
				6263	<h5>Semantics:</h5>
				6264
				6265	<p>
				6266	This intrinsic allows annotations to be put on arbitrary expressions
				6267	with arbitrary strings. This can be useful for special purpose optimizations
				6268	that want to look for these annotations. These have no other defined use, they
				6269	are ignored by code generation and optimization.
				6270	</div>
Jim Laskey	dd4ef1b	2007-03-14 19:31:19 +0000	[diff] [blame]	6271
Anton Korobeynikov	4cb8618	2008-01-15 22:31:34 +0000	[diff] [blame]	6272	<!-- _______________________________________________________________________ -->
				6273	<div class="doc_subsubsection">
				6274	<a name="int_trap">'<tt>llvm.trap</tt>' Intrinsic</a>
				6275	</div>
				6276
				6277	<div class="doc_text">
				6278
				6279	<h5>Syntax:</h5>
				6280	<pre>
				6281	declare void @llvm.trap()
				6282	</pre>
				6283
				6284	<h5>Overview:</h5>
				6285
				6286	<p>
				6287	The '<tt>llvm.trap</tt>' intrinsic
				6288	</p>
				6289
				6290	<h5>Arguments:</h5>
				6291
				6292	<p>
				6293	None
				6294	</p>
				6295
				6296	<h5>Semantics:</h5>
				6297
				6298	<p>
				6299	This intrinsics is lowered to the target dependent trap instruction. If the
				6300	target does not have a trap instruction, this intrinsic will be lowered to the
				6301	call of the abort() function.
				6302	</p>
				6303	</div>
				6304
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	6305	<!-- *********************************************************************** -->
Chris Lattner	0095054	2001-06-06 20:29:01 +0000	[diff] [blame]	6306	<hr>
Misha Brukman	daa4cb0	2004-03-01 17:47:27 +0000	[diff] [blame]	6307	<address>
				6308	<a href="http://jigsaw.w3.org/css-validator/check/referer"><img
				6309	src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
				6310	<a href="http://validator.w3.org/check/referer"><img
Chris Lattner	c7d3ab3	2008-01-04 04:33:49 +0000	[diff] [blame]	6311	src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!"></a>
Misha Brukman	daa4cb0	2004-03-01 17:47:27 +0000	[diff] [blame]	6312
				6313	<a href="mailto:sabre@nondot.org">Chris Lattner</a><br>
Reid Spencer	05fe4b0	2006-03-14 05:39:39 +0000	[diff] [blame]	6314	<a href="http://llvm.org">The LLVM Compiler Infrastructure</a><br>
Misha Brukman	daa4cb0	2004-03-01 17:47:27 +0000	[diff] [blame]	6315	Last modified: $Date$
				6316	</address>
Chris Lattner	c7d3ab3	2008-01-04 04:33:49 +0000	[diff] [blame]	6317
Misha Brukman	9d0919f	2003-11-08 01:05:38 +0000	[diff] [blame]	6318	</body>
				6319	</html>