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gerrit-public.fairphone.software / fp2-dev / platform / external / llvm / 0e451ceee3d2d65fd7b7238a7009b6703c930d98 / . / docs / LangRef.html
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4<head>
5 <title>LLVM Assembly Language Reference Manual</title>
Reid Spencer3921c742004-08-26 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 Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]10 <link rel="stylesheet" href="llvm.css" type="text/css">
11</head>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]12
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]13<body>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]14
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]15<div class="doc_title"> LLVM Language Reference Manual </div>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]16<ol>
Misha Brukman9d0919f2003-11-08 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 Lattnerfa730212004-12-09 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 Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]23 <li><a href="#linkage">Linkage Types</a></li>
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]24 <li><a href="#callingconv">Calling Conventions</a></li>
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]25 <li><a href="#globalvars">Global Variables</a></li>
Chris Lattner4e9aba72006-01-23 23:23:47 +0000[diff] [blame]26 <li><a href="#functionstructure">Functions</a></li>
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]27 <li><a href="#aliasstructure">Aliases</a></li>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]28 <li><a href="#paramattrs">Parameter Attributes</a></li>
Devang Patel2c9c3e72008-09-26 23:51:19 +0000[diff] [blame]29 <li><a href="#fnattrs">Function Attributes</a></li>
Gordon Henriksen80a75bf2007-12-10 03:18:06 +0000[diff] [blame]30 <li><a href="#gc">Garbage Collector Names</a></li>
Chris Lattner4e9aba72006-01-23 23:23:47 +0000[diff] [blame]31 <li><a href="#moduleasm">Module-Level Inline Assembly</a></li>
Reid Spencerde151942007-02-19 23:54:10 +0000[diff] [blame]32 <li><a href="#datalayout">Data Layout</a></li>
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]33 </ol>
34 </li>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]35 <li><a href="#typesystem">Type System</a>
36 <ol>
Chris Lattner4f69f462008-01-04 04:32:38 +0000[diff] [blame]37 <li><a href="#t_classifications">Type Classifications</a></li>
Robert Bocchino7b81c752006-02-17 21:18:08 +0000[diff] [blame]38 <li><a href="#t_primitive">Primitive Types</a>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]39 <ol>
Chris Lattner4f69f462008-01-04 04:32:38 +0000[diff] [blame]40 <li><a href="#t_floating">Floating Point Types</a></li>
41 <li><a href="#t_void">Void Type</a></li>
42 <li><a href="#t_label">Label Type</a></li>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]43 </ol>
44 </li>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]45 <li><a href="#t_derived">Derived Types</a>
46 <ol>
Chris Lattnerb9488a62007-12-18 06:18:21 +0000[diff] [blame]47 <li><a href="#t_integer">Integer Type</a></li>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]48 <li><a href="#t_array">Array Type</a></li>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]49 <li><a href="#t_function">Function Type</a></li>
50 <li><a href="#t_pointer">Pointer Type</a></li>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]51 <li><a href="#t_struct">Structure Type</a></li>
Andrew Lenharth75e10682006-12-08 17:13:00 +0000[diff] [blame]52 <li><a href="#t_pstruct">Packed Structure Type</a></li>
Reid Spencer485bad12007-02-15 03:07:05 +0000[diff] [blame]53 <li><a href="#t_vector">Vector Type</a></li>
Chris Lattner69c11bb2005-04-25 17:34:15 +0000[diff] [blame]54 <li><a href="#t_opaque">Opaque Type</a></li>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]55 </ol>
56 </li>
57 </ol>
58 </li>
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]59 <li><a href="#constants">Constants</a>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]60 <ol>
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]61 <li><a href="#simpleconstants">Simple Constants</a></li>
62 <li><a href="#aggregateconstants">Aggregate Constants</a></li>
63 <li><a href="#globalconstants">Global Variable and Function Addresses</a></li>
64 <li><a href="#undefvalues">Undefined Values</a></li>
65 <li><a href="#constantexprs">Constant Expressions</a></li>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]66 </ol>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]67 </li>
Chris Lattnere87d6532006-01-25 23:47:57 +0000[diff] [blame]68 <li><a href="#othervalues">Other Values</a>
69 <ol>
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]70 <li><a href="#inlineasm">Inline Assembler Expressions</a></li>
Chris Lattnere87d6532006-01-25 23:47:57 +0000[diff] [blame]71 </ol>
72 </li>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]73 <li><a href="#instref">Instruction Reference</a>
74 <ol>
75 <li><a href="#terminators">Terminator Instructions</a>
76 <ol>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]77 <li><a href="#i_ret">'<tt>ret</tt>' Instruction</a></li>
78 <li><a href="#i_br">'<tt>br</tt>' Instruction</a></li>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]79 <li><a href="#i_switch">'<tt>switch</tt>' Instruction</a></li>
80 <li><a href="#i_invoke">'<tt>invoke</tt>' Instruction</a></li>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]81 <li><a href="#i_unwind">'<tt>unwind</tt>' Instruction</a></li>
Chris Lattner35eca582004-10-16 18:04:13 +0000[diff] [blame]82 <li><a href="#i_unreachable">'<tt>unreachable</tt>' Instruction</a></li>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]83 </ol>
84 </li>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]85 <li><a href="#binaryops">Binary Operations</a>
86 <ol>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]87 <li><a href="#i_add">'<tt>add</tt>' Instruction</a></li>
88 <li><a href="#i_sub">'<tt>sub</tt>' Instruction</a></li>
89 <li><a href="#i_mul">'<tt>mul</tt>' Instruction</a></li>
Reid Spencer1628cec2006-10-26 06:15:43 +0000[diff] [blame]90 <li><a href="#i_udiv">'<tt>udiv</tt>' Instruction</a></li>
91 <li><a href="#i_sdiv">'<tt>sdiv</tt>' Instruction</a></li>
92 <li><a href="#i_fdiv">'<tt>fdiv</tt>' Instruction</a></li>
Reid Spencer0a783f72006-11-02 01:53:59 +0000[diff] [blame]93 <li><a href="#i_urem">'<tt>urem</tt>' Instruction</a></li>
94 <li><a href="#i_srem">'<tt>srem</tt>' Instruction</a></li>
95 <li><a href="#i_frem">'<tt>frem</tt>' Instruction</a></li>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]96 </ol>
97 </li>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]98 <li><a href="#bitwiseops">Bitwise Binary Operations</a>
99 <ol>
Reid Spencer8e11bf82007-02-02 13:57:07 +0000[diff] [blame]100 <li><a href="#i_shl">'<tt>shl</tt>' Instruction</a></li>
101 <li><a href="#i_lshr">'<tt>lshr</tt>' Instruction</a></li>
102 <li><a href="#i_ashr">'<tt>ashr</tt>' Instruction</a></li>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]103 <li><a href="#i_and">'<tt>and</tt>' Instruction</a></li>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]104 <li><a href="#i_or">'<tt>or</tt>' Instruction</a></li>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]105 <li><a href="#i_xor">'<tt>xor</tt>' Instruction</a></li>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]106 </ol>
107 </li>
Chris Lattner3df241e2006-04-08 23:07:04 +0000[diff] [blame]108 <li><a href="#vectorops">Vector Operations</a>
109 <ol>
110 <li><a href="#i_extractelement">'<tt>extractelement</tt>' Instruction</a></li>
111 <li><a href="#i_insertelement">'<tt>insertelement</tt>' Instruction</a></li>
112 <li><a href="#i_shufflevector">'<tt>shufflevector</tt>' Instruction</a></li>
Chris Lattner3df241e2006-04-08 23:07:04 +0000[diff] [blame]113 </ol>
114 </li>
Dan Gohmana334d5f2008-05-12 23:51:09 +0000[diff] [blame]115 <li><a href="#aggregateops">Aggregate Operations</a>
116 <ol>
117 <li><a href="#i_extractvalue">'<tt>extractvalue</tt>' Instruction</a></li>
118 <li><a href="#i_insertvalue">'<tt>insertvalue</tt>' Instruction</a></li>
119 </ol>
120 </li>
Chris Lattner884a9702006-08-15 00:45:58 +0000[diff] [blame]121 <li><a href="#memoryops">Memory Access and Addressing Operations</a>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]122 <ol>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]123 <li><a href="#i_malloc">'<tt>malloc</tt>' Instruction</a></li>
124 <li><a href="#i_free">'<tt>free</tt>' Instruction</a></li>
125 <li><a href="#i_alloca">'<tt>alloca</tt>' Instruction</a></li>
Robert Bocchino7b81c752006-02-17 21:18:08 +0000[diff] [blame]126 <li><a href="#i_load">'<tt>load</tt>' Instruction</a></li>
127 <li><a href="#i_store">'<tt>store</tt>' Instruction</a></li>
128 <li><a href="#i_getelementptr">'<tt>getelementptr</tt>' Instruction</a></li>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]129 </ol>
130 </li>
Reid Spencer2fd21e62006-11-08 01:18:52 +0000[diff] [blame]131 <li><a href="#convertops">Conversion Operations</a>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]132 <ol>
133 <li><a href="#i_trunc">'<tt>trunc .. to</tt>' Instruction</a></li>
134 <li><a href="#i_zext">'<tt>zext .. to</tt>' Instruction</a></li>
135 <li><a href="#i_sext">'<tt>sext .. to</tt>' Instruction</a></li>
136 <li><a href="#i_fptrunc">'<tt>fptrunc .. to</tt>' Instruction</a></li>
137 <li><a href="#i_fpext">'<tt>fpext .. to</tt>' Instruction</a></li>
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]138 <li><a href="#i_fptoui">'<tt>fptoui .. to</tt>' Instruction</a></li>
139 <li><a href="#i_fptosi">'<tt>fptosi .. to</tt>' Instruction</a></li>
140 <li><a href="#i_uitofp">'<tt>uitofp .. to</tt>' Instruction</a></li>
141 <li><a href="#i_sitofp">'<tt>sitofp .. to</tt>' Instruction</a></li>
Reid Spencer72679252006-11-11 21:00:47 +0000[diff] [blame]142 <li><a href="#i_ptrtoint">'<tt>ptrtoint .. to</tt>' Instruction</a></li>
143 <li><a href="#i_inttoptr">'<tt>inttoptr .. to</tt>' Instruction</a></li>
Reid Spencer5c0ef472006-11-11 23:08:07 +0000[diff] [blame]144 <li><a href="#i_bitcast">'<tt>bitcast .. to</tt>' Instruction</a></li>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]145 </ol>
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]146 </li>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]147 <li><a href="#otherops">Other Operations</a>
148 <ol>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]149 <li><a href="#i_icmp">'<tt>icmp</tt>' Instruction</a></li>
150 <li><a href="#i_fcmp">'<tt>fcmp</tt>' Instruction</a></li>
Nate Begemanac80ade2008-05-12 19:01:56 +0000[diff] [blame]151 <li><a href="#i_vicmp">'<tt>vicmp</tt>' Instruction</a></li>
152 <li><a href="#i_vfcmp">'<tt>vfcmp</tt>' Instruction</a></li>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]153 <li><a href="#i_phi">'<tt>phi</tt>' Instruction</a></li>
Chris Lattnercc37aae2004-03-12 05:50:16 +0000[diff] [blame]154 <li><a href="#i_select">'<tt>select</tt>' Instruction</a></li>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]155 <li><a href="#i_call">'<tt>call</tt>' Instruction</a></li>
Chris Lattnerfb6977d2006-01-13 23:26:01 +0000[diff] [blame]156 <li><a href="#i_va_arg">'<tt>va_arg</tt>' Instruction</a></li>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]157 </ol>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]158 </li>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]159 </ol>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]160 </li>
Chris Lattnerd9ad5b32003-05-08 04:57:36 +0000[diff] [blame]161 <li><a href="#intrinsics">Intrinsic Functions</a>
Chris Lattnerd9ad5b32003-05-08 04:57:36 +0000[diff] [blame]162 <ol>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]163 <li><a href="#int_varargs">Variable Argument Handling Intrinsics</a>
164 <ol>
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]165 <li><a href="#int_va_start">'<tt>llvm.va_start</tt>' Intrinsic</a></li>
166 <li><a href="#int_va_end">'<tt>llvm.va_end</tt>' Intrinsic</a></li>
167 <li><a href="#int_va_copy">'<tt>llvm.va_copy</tt>' Intrinsic</a></li>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]168 </ol>
169 </li>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]170 <li><a href="#int_gc">Accurate Garbage Collection Intrinsics</a>
171 <ol>
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]172 <li><a href="#int_gcroot">'<tt>llvm.gcroot</tt>' Intrinsic</a></li>
173 <li><a href="#int_gcread">'<tt>llvm.gcread</tt>' Intrinsic</a></li>
174 <li><a href="#int_gcwrite">'<tt>llvm.gcwrite</tt>' Intrinsic</a></li>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]175 </ol>
176 </li>
Chris Lattner10610642004-02-14 04:08:35 +0000[diff] [blame]177 <li><a href="#int_codegen">Code Generator Intrinsics</a>
178 <ol>
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]179 <li><a href="#int_returnaddress">'<tt>llvm.returnaddress</tt>' Intrinsic</a></li>
180 <li><a href="#int_frameaddress">'<tt>llvm.frameaddress</tt>' Intrinsic</a></li>
181 <li><a href="#int_stacksave">'<tt>llvm.stacksave</tt>' Intrinsic</a></li>
182 <li><a href="#int_stackrestore">'<tt>llvm.stackrestore</tt>' Intrinsic</a></li>
183 <li><a href="#int_prefetch">'<tt>llvm.prefetch</tt>' Intrinsic</a></li>
184 <li><a href="#int_pcmarker">'<tt>llvm.pcmarker</tt>' Intrinsic</a></li>
185 <li><a href="#int_readcyclecounter"><tt>llvm.readcyclecounter</tt>' Intrinsic</a></li>
John Criswell7123e272004-04-09 16:43:20 +0000[diff] [blame]186 </ol>
187 </li>
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]188 <li><a href="#int_libc">Standard C Library Intrinsics</a>
189 <ol>
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]190 <li><a href="#int_memcpy">'<tt>llvm.memcpy.*</tt>' Intrinsic</a></li>
191 <li><a href="#int_memmove">'<tt>llvm.memmove.*</tt>' Intrinsic</a></li>
192 <li><a href="#int_memset">'<tt>llvm.memset.*</tt>' Intrinsic</a></li>
193 <li><a href="#int_sqrt">'<tt>llvm.sqrt.*</tt>' Intrinsic</a></li>
194 <li><a href="#int_powi">'<tt>llvm.powi.*</tt>' Intrinsic</a></li>
Dan Gohman91c284c2007-10-15 20:30:11 +0000[diff] [blame]195 <li><a href="#int_sin">'<tt>llvm.sin.*</tt>' Intrinsic</a></li>
196 <li><a href="#int_cos">'<tt>llvm.cos.*</tt>' Intrinsic</a></li>
197 <li><a href="#int_pow">'<tt>llvm.pow.*</tt>' Intrinsic</a></li>
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]198 </ol>
199 </li>
Nate Begeman7e36c472006-01-13 23:26:38 +0000[diff] [blame]200 <li><a href="#int_manip">Bit Manipulation Intrinsics</a>
Andrew Lenharthec370fd2005-05-03 18:01:48 +0000[diff] [blame]201 <ol>
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]202 <li><a href="#int_bswap">'<tt>llvm.bswap.*</tt>' Intrinsics</a></li>
Chris Lattner8a886be2006-01-16 22:34:14 +0000[diff] [blame]203 <li><a href="#int_ctpop">'<tt>llvm.ctpop.*</tt>' Intrinsic </a></li>
204 <li><a href="#int_ctlz">'<tt>llvm.ctlz.*</tt>' Intrinsic </a></li>
205 <li><a href="#int_cttz">'<tt>llvm.cttz.*</tt>' Intrinsic </a></li>
Reid Spencerf86037f2007-04-11 23:23:49 +0000[diff] [blame]206 <li><a href="#int_part_select">'<tt>llvm.part.select.*</tt>' Intrinsic </a></li>
207 <li><a href="#int_part_set">'<tt>llvm.part.set.*</tt>' Intrinsic </a></li>
Andrew Lenharthec370fd2005-05-03 18:01:48 +0000[diff] [blame]208 </ol>
209 </li>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]210 <li><a href="#int_debugger">Debugger intrinsics</a></li>
Jim Laskeydd4ef1b2007-03-14 19:31:19 +0000[diff] [blame]211 <li><a href="#int_eh">Exception Handling intrinsics</a></li>
Duncan Sandsf7331b32007-09-11 14:10:23 +0000[diff] [blame]212 <li><a href="#int_trampoline">Trampoline Intrinsic</a>
Duncan Sands36397f52007-07-27 12:58:54 +0000[diff] [blame]213 <ol>
214 <li><a href="#int_it">'<tt>llvm.init.trampoline</tt>' Intrinsic</a></li>
Duncan Sands36397f52007-07-27 12:58:54 +0000[diff] [blame]215 </ol>
216 </li>
Andrew Lenharth22c5c1b2008-02-16 01:24:58 +0000[diff] [blame]217 <li><a href="#int_atomics">Atomic intrinsics</a>
218 <ol>
Andrew Lenharthab0b9492008-02-21 06:45:13 +0000[diff] [blame]219 <li><a href="#int_memory_barrier"><tt>llvm.memory_barrier</tt></a></li>
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]220 <li><a href="#int_atomic_cmp_swap"><tt>llvm.atomic.cmp.swap</tt></a></li>
Andrew Lenharthab0b9492008-02-21 06:45:13 +0000[diff] [blame]221 <li><a href="#int_atomic_swap"><tt>llvm.atomic.swap</tt></a></li>
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]222 <li><a href="#int_atomic_load_add"><tt>llvm.atomic.load.add</tt></a></li>
223 <li><a href="#int_atomic_load_sub"><tt>llvm.atomic.load.sub</tt></a></li>
224 <li><a href="#int_atomic_load_and"><tt>llvm.atomic.load.and</tt></a></li>
225 <li><a href="#int_atomic_load_nand"><tt>llvm.atomic.load.nand</tt></a></li>
226 <li><a href="#int_atomic_load_or"><tt>llvm.atomic.load.or</tt></a></li>
227 <li><a href="#int_atomic_load_xor"><tt>llvm.atomic.load.xor</tt></a></li>
228 <li><a href="#int_atomic_load_max"><tt>llvm.atomic.load.max</tt></a></li>
229 <li><a href="#int_atomic_load_min"><tt>llvm.atomic.load.min</tt></a></li>
230 <li><a href="#int_atomic_load_umax"><tt>llvm.atomic.load.umax</tt></a></li>
231 <li><a href="#int_atomic_load_umin"><tt>llvm.atomic.load.umin</tt></a></li>
Andrew Lenharth22c5c1b2008-02-16 01:24:58 +0000[diff] [blame]232 </ol>
233 </li>
Reid Spencer20677642007-07-20 19:59:11 +0000[diff] [blame]234 <li><a href="#int_general">General intrinsics</a>
Tanya Lattner6d806e92007-06-15 20:50:54 +0000[diff] [blame]235 <ol>
Reid Spencer20677642007-07-20 19:59:11 +0000[diff] [blame]236 <li><a href="#int_var_annotation">
Tanya Lattner91d0b882007-09-22 00:01:26 +0000[diff] [blame]237 <tt>llvm.var.annotation</tt>' Intrinsic</a></li>
Tanya Lattnerb6367882007-09-21 22:59:12 +0000[diff] [blame]238 <li><a href="#int_annotation">
Tanya Lattner91d0b882007-09-22 00:01:26 +0000[diff] [blame]239 <tt>llvm.annotation.*</tt>' Intrinsic</a></li>
Anton Korobeynikov4cb86182008-01-15 22:31:34 +0000[diff] [blame]240 <li><a href="#int_trap">
241 <tt>llvm.trap</tt>' Intrinsic</a></li>
Tanya Lattnerb6367882007-09-21 22:59:12 +0000[diff] [blame]242 </ol>
Tanya Lattner6d806e92007-06-15 20:50:54 +0000[diff] [blame]243 </li>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]244 </ol>
245 </li>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]246</ol>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]247
248<div class="doc_author">
249 <p>Written by <a href="mailto:sabre@nondot.org">Chris Lattner</a>
250 and <a href="mailto:vadve@cs.uiuc.edu">Vikram Adve</a></p>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]251</div>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]252
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]253<!-- *********************************************************************** -->
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]254<div class="doc_section"> <a name="abstract">Abstract </a></div>
255<!-- *********************************************************************** -->
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]256
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]257<div class="doc_text">
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]258<p>This document is a reference manual for the LLVM assembly language.
Bill Wendling837f39b2008-08-05 22:29:16 +0000[diff] [blame]259LLVM is a Static Single Assignment (SSA) based representation that provides
Chris Lattnerd3eda892008-08-05 18:29:16 +0000[diff] [blame]260type safety, low-level operations, flexibility, and the capability of
261representing 'all' high-level languages cleanly. It is the common code
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]262representation used throughout all phases of the LLVM compilation
263strategy.</p>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]264</div>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]265
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]266<!-- *********************************************************************** -->
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]267<div class="doc_section"> <a name="introduction">Introduction</a> </div>
268<!-- *********************************************************************** -->
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]269
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]270<div class="doc_text">
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]271
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]272<p>The LLVM code representation is designed to be used in three
Gabor Greif04367bf2007-07-06 22:07:22 +0000[diff] [blame]273different forms: as an in-memory compiler IR, as an on-disk bitcode
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]274representation (suitable for fast loading by a Just-In-Time compiler),
275and as a human readable assembly language representation. This allows
276LLVM to provide a powerful intermediate representation for efficient
277compiler transformations and analysis, while providing a natural means
278to debug and visualize the transformations. The three different forms
279of LLVM are all equivalent. This document describes the human readable
280representation and notation.</p>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]281
John Criswellc1f786c2005-05-13 22:25:59 +0000[diff] [blame]282<p>The LLVM representation aims to be light-weight and low-level
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]283while being expressive, typed, and extensible at the same time. It
284aims to be a "universal IR" of sorts, by being at a low enough level
285that high-level ideas may be cleanly mapped to it (similar to how
286microprocessors are "universal IR's", allowing many source languages to
287be mapped to them). By providing type information, LLVM can be used as
288the target of optimizations: for example, through pointer analysis, it
289can be proven that a C automatic variable is never accessed outside of
290the current function... allowing it to be promoted to a simple SSA
291value instead of a memory location.</p>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]292
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]293</div>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]294
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]295<!-- _______________________________________________________________________ -->
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]296<div class="doc_subsubsection"> <a name="wellformed">Well-Formedness</a> </div>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]297
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]298<div class="doc_text">
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]299
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]300<p>It is important to note that this document describes 'well formed'
301LLVM assembly language. There is a difference between what the parser
302accepts and what is considered 'well formed'. For example, the
303following instruction is syntactically okay, but not well formed:</p>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]304
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]305<div class="doc_code">
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]306<pre>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]307%x = <a href="#i_add">add</a> i32 1, %x
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]308</pre>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]309</div>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]310
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]311<p>...because the definition of <tt>%x</tt> does not dominate all of
312its uses. The LLVM infrastructure provides a verification pass that may
313be used to verify that an LLVM module is well formed. This pass is
John Criswellc1f786c2005-05-13 22:25:59 +0000[diff] [blame]314automatically run by the parser after parsing input assembly and by
Gabor Greif04367bf2007-07-06 22:07:22 +0000[diff] [blame]315the optimizer before it outputs bitcode. The violations pointed out
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]316by the verifier pass indicate bugs in transformation passes or input to
317the parser.</p>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]318</div>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]319
Chris Lattnercc689392007-10-03 17:34:29 +0000[diff] [blame]320<!-- Describe the typesetting conventions here. -->
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]321
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]322<!-- *********************************************************************** -->
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]323<div class="doc_section"> <a name="identifiers">Identifiers</a> </div>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]324<!-- *********************************************************************** -->
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]325
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]326<div class="doc_text">
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]327
Reid Spencer2c452282007-08-07 14:34:28 +0000[diff] [blame]328 <p>LLVM identifiers come in two basic types: global and local. Global
329 identifiers (functions, global variables) begin with the @ character. Local
330 identifiers (register names, types) begin with the % character. Additionally,
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]331 there are three different formats for identifiers, for different purposes:</p>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]332
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]333<ol>
Reid Spencer2c452282007-08-07 14:34:28 +0000[diff] [blame]334 <li>Named values are represented as a string of characters with their prefix.
335 For example, %foo, @DivisionByZero, %a.really.long.identifier. The actual
336 regular expression used is '<tt>[%@][a-zA-Z$._][a-zA-Z$._0-9]*</tt>'.
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]337 Identifiers which require other characters in their names can be surrounded
Reid Spencer2c452282007-08-07 14:34:28 +0000[diff] [blame]338 with quotes. In this way, anything except a <tt>&quot;</tt> character can
339 be used in a named value.</li>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]340
Reid Spencer2c452282007-08-07 14:34:28 +0000[diff] [blame]341 <li>Unnamed values are represented as an unsigned numeric value with their
342 prefix. For example, %12, @2, %44.</li>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]343
Reid Spencercc16dc32004-12-09 18:02:53 +0000[diff] [blame]344 <li>Constants, which are described in a <a href="#constants">section about
345 constants</a>, below.</li>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]346</ol>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]347
Reid Spencer2c452282007-08-07 14:34:28 +0000[diff] [blame]348<p>LLVM requires that values start with a prefix for two reasons: Compilers
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]349don't need to worry about name clashes with reserved words, and the set of
350reserved words may be expanded in the future without penalty. Additionally,
351unnamed identifiers allow a compiler to quickly come up with a temporary
352variable without having to avoid symbol table conflicts.</p>
353
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]354<p>Reserved words in LLVM are very similar to reserved words in other
Reid Spencer5c0ef472006-11-11 23:08:07 +0000[diff] [blame]355languages. There are keywords for different opcodes
356('<tt><a href="#i_add">add</a></tt>',
357 '<tt><a href="#i_bitcast">bitcast</a></tt>',
358 '<tt><a href="#i_ret">ret</a></tt>', etc...), for primitive type names ('<tt><a
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]359href="#t_void">void</a></tt>', '<tt><a href="#t_primitive">i32</a></tt>', etc...),
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]360and others. These reserved words cannot conflict with variable names, because
Reid Spencer2c452282007-08-07 14:34:28 +0000[diff] [blame]361none of them start with a prefix character ('%' or '@').</p>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]362
363<p>Here is an example of LLVM code to multiply the integer variable
364'<tt>%X</tt>' by 8:</p>
365
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]366<p>The easy way:</p>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]367
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]368<div class="doc_code">
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]369<pre>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]370%result = <a href="#i_mul">mul</a> i32 %X, 8
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]371</pre>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]372</div>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]373
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]374<p>After strength reduction:</p>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]375
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]376<div class="doc_code">
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]377<pre>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]378%result = <a href="#i_shl">shl</a> i32 %X, i8 3
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]379</pre>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]380</div>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]381
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]382<p>And the hard way:</p>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]383
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]384<div class="doc_code">
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]385<pre>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]386<a href="#i_add">add</a> i32 %X, %X <i>; yields {i32}:%0</i>
387<a href="#i_add">add</a> i32 %0, %0 <i>; yields {i32}:%1</i>
388%result = <a href="#i_add">add</a> i32 %1, %1
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]389</pre>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]390</div>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]391
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]392<p>This last way of multiplying <tt>%X</tt> by 8 illustrates several
393important lexical features of LLVM:</p>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]394
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]395<ol>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]396
397 <li>Comments are delimited with a '<tt>;</tt>' and go until the end of
398 line.</li>
399
400 <li>Unnamed temporaries are created when the result of a computation is not
401 assigned to a named value.</li>
402
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]403 <li>Unnamed temporaries are numbered sequentially</li>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]404
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]405</ol>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]406
John Criswelle4c57cc2005-05-12 16:52:32 +0000[diff] [blame]407<p>...and it also shows a convention that we follow in this document. When
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]408demonstrating instructions, we will follow an instruction with a comment that
409defines the type and name of value produced. Comments are shown in italic
410text.</p>
411
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]412</div>
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]413
414<!-- *********************************************************************** -->
415<div class="doc_section"> <a name="highlevel">High Level Structure</a> </div>
416<!-- *********************************************************************** -->
417
418<!-- ======================================================================= -->
419<div class="doc_subsection"> <a name="modulestructure">Module Structure</a>
420</div>
421
422<div class="doc_text">
423
424<p>LLVM programs are composed of "Module"s, each of which is a
425translation unit of the input programs. Each module consists of
426functions, global variables, and symbol table entries. Modules may be
427combined together with the LLVM linker, which merges function (and
428global variable) definitions, resolves forward declarations, and merges
429symbol table entries. Here is an example of the "hello world" module:</p>
430
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]431<div class="doc_code">
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]432<pre><i>; Declare the string constant as a global constant...</i>
Chris Lattnera89e5f12007-06-12 17:00:26 +0000[diff] [blame]433<a href="#identifiers">@.LC0</a> = <a href="#linkage_internal">internal</a> <a
434 href="#globalvars">constant</a> <a href="#t_array">[13 x i8]</a> c"hello world\0A\00" <i>; [13 x i8]*</i>
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]435
436<i>; External declaration of the puts function</i>
Chris Lattnera89e5f12007-06-12 17:00:26 +0000[diff] [blame]437<a href="#functionstructure">declare</a> i32 @puts(i8 *) <i>; i32(i8 *)* </i>
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]438
439<i>; Definition of main function</i>
Chris Lattnera89e5f12007-06-12 17:00:26 +0000[diff] [blame]440define i32 @main() { <i>; i32()* </i>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]441 <i>; Convert [13x i8 ]* to i8 *...</i>
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]442 %cast210 = <a
Chris Lattner6c0955b2007-06-12 17:01:15 +0000[diff] [blame]443 href="#i_getelementptr">getelementptr</a> [13 x i8 ]* @.LC0, i64 0, i64 0 <i>; i8 *</i>
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]444
445 <i>; Call puts function to write out the string to stdout...</i>
446 <a
Chris Lattnera89e5f12007-06-12 17:00:26 +0000[diff] [blame]447 href="#i_call">call</a> i32 @puts(i8 * %cast210) <i>; i32</i>
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]448 <a
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]449 href="#i_ret">ret</a> i32 0<br>}<br>
450</pre>
451</div>
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]452
453<p>This example is made up of a <a href="#globalvars">global variable</a>
454named "<tt>.LC0</tt>", an external declaration of the "<tt>puts</tt>"
455function, and a <a href="#functionstructure">function definition</a>
456for "<tt>main</tt>".</p>
457
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]458<p>In general, a module is made up of a list of global values,
459where both functions and global variables are global values. Global values are
460represented by a pointer to a memory location (in this case, a pointer to an
461array of char, and a pointer to a function), and have one of the following <a
462href="#linkage">linkage types</a>.</p>
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]463
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]464</div>
465
466<!-- ======================================================================= -->
467<div class="doc_subsection">
468 <a name="linkage">Linkage Types</a>
469</div>
470
471<div class="doc_text">
472
473<p>
474All Global Variables and Functions have one of the following types of linkage:
475</p>
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]476
477<dl>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]478
Dale Johannesen2307a7f2008-05-23 23:13:41 +0000[diff] [blame]479 <dt><tt><b><a name="linkage_internal">internal</a></b></tt>: </dt>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]480
481 <dd>Global values with internal linkage are only directly accessible by
482 objects in the current module. In particular, linking code into a module with
483 an internal global value may cause the internal to be renamed as necessary to
484 avoid collisions. Because the symbol is internal to the module, all
485 references can be updated. This corresponds to the notion of the
Chris Lattner4887bd82007-01-14 06:51:48 +0000[diff] [blame]486 '<tt>static</tt>' keyword in C.
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]487 </dd>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]488
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]489 <dt><tt><b><a name="linkage_linkonce">linkonce</a></b></tt>: </dt>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]490
Chris Lattner4887bd82007-01-14 06:51:48 +0000[diff] [blame]491 <dd>Globals with "<tt>linkonce</tt>" linkage are merged with other globals of
492 the same name when linkage occurs. This is typically used to implement
493 inline functions, templates, or other code which must be generated in each
494 translation unit that uses it. Unreferenced <tt>linkonce</tt> globals are
495 allowed to be discarded.
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]496 </dd>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]497
Dale Johannesen2307a7f2008-05-23 23:13:41 +0000[diff] [blame]498 <dt><tt><b><a name="linkage_common">common</a></b></tt>: </dt>
499
500 <dd>"<tt>common</tt>" linkage is exactly the same as <tt>linkonce</tt>
501 linkage, except that unreferenced <tt>common</tt> globals may not be
502 discarded. This is used for globals that may be emitted in multiple
503 translation units, but that are not guaranteed to be emitted into every
504 translation unit that uses them. One example of this is tentative
505 definitions in C, such as "<tt>int X;</tt>" at global scope.
506 </dd>
507
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]508 <dt><tt><b><a name="linkage_weak">weak</a></b></tt>: </dt>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]509
Dale Johannesen2307a7f2008-05-23 23:13:41 +0000[diff] [blame]510 <dd>"<tt>weak</tt>" linkage is the same as <tt>common</tt> linkage, except
511 that some targets may choose to emit different assembly sequences for them
512 for target-dependent reasons. This is used for globals that are declared
513 "weak" in C source code.
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]514 </dd>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]515
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]516 <dt><tt><b><a name="linkage_appending">appending</a></b></tt>: </dt>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]517
518 <dd>"<tt>appending</tt>" linkage may only be applied to global variables of
519 pointer to array type. When two global variables with appending linkage are
520 linked together, the two global arrays are appended together. This is the
521 LLVM, typesafe, equivalent of having the system linker append together
522 "sections" with identical names when .o files are linked.
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]523 </dd>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]524
Anton Korobeynikov7f705592007-01-12 19:20:47 +0000[diff] [blame]525 <dt><tt><b><a name="linkage_externweak">extern_weak</a></b></tt>: </dt>
Chris Lattnerd3eda892008-08-05 18:29:16 +0000[diff] [blame]526 <dd>The semantics of this linkage follow the ELF object file model: the
527 symbol is weak until linked, if not linked, the symbol becomes null instead
528 of being an undefined reference.
Anton Korobeynikov7f705592007-01-12 19:20:47 +0000[diff] [blame]529 </dd>
Anton Korobeynikov7f705592007-01-12 19:20:47 +0000[diff] [blame]530
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]531 <dt><tt><b><a name="linkage_external">externally visible</a></b></tt>:</dt>
Chris Lattnere5d947b2004-12-09 16:36:40 +0000[diff] [blame]532
533 <dd>If none of the above identifiers are used, the global is externally
534 visible, meaning that it participates in linkage and can be used to resolve
535 external symbol references.
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]536 </dd>
Reid Spencerc8910842007-04-11 23:49:50 +0000[diff] [blame]537</dl>
Anton Korobeynikovb74ed072006-09-14 18:23:27 +0000[diff] [blame]538
Anton Korobeynikovb74ed072006-09-14 18:23:27 +0000[diff] [blame]539 <p>
540 The next two types of linkage are targeted for Microsoft Windows platform
541 only. They are designed to support importing (exporting) symbols from (to)
Chris Lattnerd3eda892008-08-05 18:29:16 +0000[diff] [blame]542 DLLs (Dynamic Link Libraries).
Anton Korobeynikovb74ed072006-09-14 18:23:27 +0000[diff] [blame]543 </p>
544
Anton Korobeynikov7f705592007-01-12 19:20:47 +0000[diff] [blame]545 <dl>
Anton Korobeynikovb74ed072006-09-14 18:23:27 +0000[diff] [blame]546 <dt><tt><b><a name="linkage_dllimport">dllimport</a></b></tt>: </dt>
547
548 <dd>"<tt>dllimport</tt>" linkage causes the compiler to reference a function
549 or variable via a global pointer to a pointer that is set up by the DLL
550 exporting the symbol. On Microsoft Windows targets, the pointer name is
551 formed by combining <code>_imp__</code> and the function or variable name.
552 </dd>
553
554 <dt><tt><b><a name="linkage_dllexport">dllexport</a></b></tt>: </dt>
555
556 <dd>"<tt>dllexport</tt>" linkage causes the compiler to provide a global
557 pointer to a pointer in a DLL, so that it can be referenced with the
558 <tt>dllimport</tt> attribute. On Microsoft Windows targets, the pointer
559 name is formed by combining <code>_imp__</code> and the function or variable
560 name.
561 </dd>
562
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]563</dl>
564
Anton Korobeynikov7f705592007-01-12 19:20:47 +0000[diff] [blame]565<p><a name="linkage_external"></a>For example, since the "<tt>.LC0</tt>"
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]566variable is defined to be internal, if another module defined a "<tt>.LC0</tt>"
567variable and was linked with this one, one of the two would be renamed,
568preventing a collision. Since "<tt>main</tt>" and "<tt>puts</tt>" are
569external (i.e., lacking any linkage declarations), they are accessible
Reid Spencerac8d2762007-01-05 00:59:10 +0000[diff] [blame]570outside of the current module.</p>
571<p>It is illegal for a function <i>declaration</i>
572to have any linkage type other than "externally visible", <tt>dllimport</tt>,
Anton Korobeynikov7f705592007-01-12 19:20:47 +0000[diff] [blame]573or <tt>extern_weak</tt>.</p>
Anton Korobeynikov8b0a8c82007-04-25 14:27:10 +0000[diff] [blame]574<p>Aliases can have only <tt>external</tt>, <tt>internal</tt> and <tt>weak</tt>
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]575linkages.</p>
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]576</div>
577
578<!-- ======================================================================= -->
579<div class="doc_subsection">
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]580 <a name="callingconv">Calling Conventions</a>
581</div>
582
583<div class="doc_text">
584
585<p>LLVM <a href="#functionstructure">functions</a>, <a href="#i_call">calls</a>
586and <a href="#i_invoke">invokes</a> can all have an optional calling convention
587specified for the call. The calling convention of any pair of dynamic
588caller/callee must match, or the behavior of the program is undefined. The
589following calling conventions are supported by LLVM, and more may be added in
590the future:</p>
591
592<dl>
593 <dt><b>"<tt>ccc</tt>" - The C calling convention</b>:</dt>
594
595 <dd>This calling convention (the default if no other calling convention is
596 specified) matches the target C calling conventions. This calling convention
John Criswelle4c57cc2005-05-12 16:52:32 +0000[diff] [blame]597 supports varargs function calls and tolerates some mismatch in the declared
Reid Spencerc28d2bc2006-12-31 21:30:18 +0000[diff] [blame]598 prototype and implemented declaration of the function (as does normal C).
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]599 </dd>
600
601 <dt><b>"<tt>fastcc</tt>" - The fast calling convention</b>:</dt>
602
603 <dd>This calling convention attempts to make calls as fast as possible
604 (e.g. by passing things in registers). This calling convention allows the
605 target to use whatever tricks it wants to produce fast code for the target,
Chris Lattnerd3eda892008-08-05 18:29:16 +0000[diff] [blame]606 without having to conform to an externally specified ABI (Application Binary
607 Interface). Implementations of this convention should allow arbitrary
Arnold Schwaighofer9097d142008-05-14 09:17:12 +0000[diff] [blame]608 <a href="CodeGenerator.html#tailcallopt">tail call optimization</a> to be
609 supported. This calling convention does not support varargs and requires the
610 prototype of all callees to exactly match the prototype of the function
611 definition.
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]612 </dd>
613
614 <dt><b>"<tt>coldcc</tt>" - The cold calling convention</b>:</dt>
615
616 <dd>This calling convention attempts to make code in the caller as efficient
617 as possible under the assumption that the call is not commonly executed. As
618 such, these calls often preserve all registers so that the call does not break
619 any live ranges in the caller side. This calling convention does not support
620 varargs and requires the prototype of all callees to exactly match the
621 prototype of the function definition.
622 </dd>
623
Chris Lattnercfe6b372005-05-07 01:46:40 +0000[diff] [blame]624 <dt><b>"<tt>cc &lt;<em>n</em>&gt;</tt>" - Numbered convention</b>:</dt>
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]625
626 <dd>Any calling convention may be specified by number, allowing
627 target-specific calling conventions to be used. Target specific calling
628 conventions start at 64.
629 </dd>
Chris Lattnercfe6b372005-05-07 01:46:40 +0000[diff] [blame]630</dl>
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]631
632<p>More calling conventions can be added/defined on an as-needed basis, to
633support pascal conventions or any other well-known target-independent
634convention.</p>
635
636</div>
637
638<!-- ======================================================================= -->
639<div class="doc_subsection">
Anton Korobeynikov8cea37b2007-01-23 12:35:46 +0000[diff] [blame]640 <a name="visibility">Visibility Styles</a>
641</div>
642
643<div class="doc_text">
644
645<p>
646All Global Variables and Functions have one of the following visibility styles:
647</p>
648
649<dl>
650 <dt><b>"<tt>default</tt>" - Default style</b>:</dt>
651
Chris Lattnerd3eda892008-08-05 18:29:16 +0000[diff] [blame]652 <dd>On targets that use the ELF object file format, default visibility means
653 that the declaration is visible to other
Anton Korobeynikov8cea37b2007-01-23 12:35:46 +0000[diff] [blame]654 modules and, in shared libraries, means that the declared entity may be
655 overridden. On Darwin, default visibility means that the declaration is
656 visible to other modules. Default visibility corresponds to "external
657 linkage" in the language.
658 </dd>
659
660 <dt><b>"<tt>hidden</tt>" - Hidden style</b>:</dt>
661
662 <dd>Two declarations of an object with hidden visibility refer to the same
663 object if they are in the same shared object. Usually, hidden visibility
664 indicates that the symbol will not be placed into the dynamic symbol table,
665 so no other module (executable or shared library) can reference it
666 directly.
667 </dd>
668
Anton Korobeynikov6f9896f2007-04-29 18:35:00 +0000[diff] [blame]669 <dt><b>"<tt>protected</tt>" - Protected style</b>:</dt>
670
671 <dd>On ELF, protected visibility indicates that the symbol will be placed in
672 the dynamic symbol table, but that references within the defining module will
673 bind to the local symbol. That is, the symbol cannot be overridden by another
674 module.
675 </dd>
Anton Korobeynikov8cea37b2007-01-23 12:35:46 +0000[diff] [blame]676</dl>
677
678</div>
679
680<!-- ======================================================================= -->
681<div class="doc_subsection">
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]682 <a name="globalvars">Global Variables</a>
683</div>
684
685<div class="doc_text">
686
Chris Lattner3689a342005-02-12 19:30:21 +0000[diff] [blame]687<p>Global variables define regions of memory allocated at compilation time
Chris Lattner88f6c462005-11-12 00:45:07 +0000[diff] [blame]688instead of run-time. Global variables may optionally be initialized, may have
Anton Korobeynikov8b0a8c82007-04-25 14:27:10 +0000[diff] [blame]689an explicit section to be placed in, and may have an optional explicit alignment
690specified. A variable may be defined as "thread_local", which means that it
691will not be shared by threads (each thread will have a separated copy of the
692variable). A variable may be defined as a global "constant," which indicates
693that the contents of the variable will <b>never</b> be modified (enabling better
Chris Lattner3689a342005-02-12 19:30:21 +0000[diff] [blame]694optimization, allowing the global data to be placed in the read-only section of
695an executable, etc). Note that variables that need runtime initialization
John Criswell0ec250c2005-10-24 16:17:18 +0000[diff] [blame]696cannot be marked "constant" as there is a store to the variable.</p>
Chris Lattner3689a342005-02-12 19:30:21 +0000[diff] [blame]697
698<p>
699LLVM explicitly allows <em>declarations</em> of global variables to be marked
700constant, even if the final definition of the global is not. This capability
701can be used to enable slightly better optimization of the program, but requires
702the language definition to guarantee that optimizations based on the
703'constantness' are valid for the translation units that do not include the
704definition.
705</p>
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]706
707<p>As SSA values, global variables define pointer values that are in
708scope (i.e. they dominate) all basic blocks in the program. Global
709variables always define a pointer to their "content" type because they
710describe a region of memory, and all memory objects in LLVM are
711accessed through pointers.</p>
712
Christopher Lamb284d9922007-12-11 09:31:00 +0000[diff] [blame]713<p>A global variable may be declared to reside in a target-specifc numbered
714address space. For targets that support them, address spaces may affect how
715optimizations are performed and/or what target instructions are used to access
Christopher Lambd49e18d2007-12-12 08:44:39 +0000[diff] [blame]716the variable. The default address space is zero. The address space qualifier
717must precede any other attributes.</p>
Christopher Lamb284d9922007-12-11 09:31:00 +0000[diff] [blame]718
Chris Lattner88f6c462005-11-12 00:45:07 +0000[diff] [blame]719<p>LLVM allows an explicit section to be specified for globals. If the target
720supports it, it will emit globals to the section specified.</p>
721
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]722<p>An explicit alignment may be specified for a global. If not present, or if
723the alignment is set to zero, the alignment of the global is set by the target
724to whatever it feels convenient. If an explicit alignment is specified, the
725global is forced to have at least that much alignment. All alignments must be
726a power of 2.</p>
727
Christopher Lamb284d9922007-12-11 09:31:00 +0000[diff] [blame]728<p>For example, the following defines a global in a numbered address space with
729an initializer, section, and alignment:</p>
Chris Lattner68027ea2007-01-14 00:27:09 +0000[diff] [blame]730
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]731<div class="doc_code">
Chris Lattner68027ea2007-01-14 00:27:09 +0000[diff] [blame]732<pre>
Christopher Lamb284d9922007-12-11 09:31:00 +0000[diff] [blame]733@G = constant float 1.0 addrspace(5), section "foo", align 4
Chris Lattner68027ea2007-01-14 00:27:09 +0000[diff] [blame]734</pre>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]735</div>
Chris Lattner68027ea2007-01-14 00:27:09 +0000[diff] [blame]736
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]737</div>
738
739
740<!-- ======================================================================= -->
741<div class="doc_subsection">
742 <a name="functionstructure">Functions</a>
743</div>
744
745<div class="doc_text">
746
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]747<p>LLVM function definitions consist of the "<tt>define</tt>" keyord,
748an optional <a href="#linkage">linkage type</a>, an optional
Anton Korobeynikov8cea37b2007-01-23 12:35:46 +0000[diff] [blame]749<a href="#visibility">visibility style</a>, an optional
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]750<a href="#callingconv">calling convention</a>, a return type, an optional
751<a href="#paramattrs">parameter attribute</a> for the return type, a function
752name, a (possibly empty) argument list (each with optional
Devang Patelf642f472008-10-06 18:50:38 +0000[diff] [blame]753<a href="#paramattrs">parameter attributes</a>), optional
754<a href="#fnattrs">function attributes</a>, an optional section,
755an optional alignment, an optional <a href="#gc">garbage collector name</a>,
Chris Lattner0c46a7d2008-10-04 18:10:21 +0000[diff] [blame]756an opening curly brace, a list of basic blocks, and a closing curly brace.
Anton Korobeynikov8cea37b2007-01-23 12:35:46 +0000[diff] [blame]757
758LLVM function declarations consist of the "<tt>declare</tt>" keyword, an
759optional <a href="#linkage">linkage type</a>, an optional
760<a href="#visibility">visibility style</a>, an optional
761<a href="#callingconv">calling convention</a>, a return type, an optional
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]762<a href="#paramattrs">parameter attribute</a> for the return type, a function
Gordon Henriksen80a75bf2007-12-10 03:18:06 +0000[diff] [blame]763name, a possibly empty list of arguments, an optional alignment, and an optional
Gordon Henriksene754abe2007-12-10 03:30:21 +0000[diff] [blame]764<a href="#gc">garbage collector name</a>.</p>
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]765
Chris Lattnerd3eda892008-08-05 18:29:16 +0000[diff] [blame]766<p>A function definition contains a list of basic blocks, forming the CFG
767(Control Flow Graph) for
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]768the function. Each basic block may optionally start with a label (giving the
769basic block a symbol table entry), contains a list of instructions, and ends
770with a <a href="#terminators">terminator</a> instruction (such as a branch or
771function return).</p>
772
Chris Lattner4a3c9012007-06-08 16:52:14 +0000[diff] [blame]773<p>The first basic block in a function is special in two ways: it is immediately
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]774executed on entrance to the function, and it is not allowed to have predecessor
775basic blocks (i.e. there can not be any branches to the entry block of a
776function). Because the block can have no predecessors, it also cannot have any
777<a href="#i_phi">PHI nodes</a>.</p>
778
Chris Lattner88f6c462005-11-12 00:45:07 +0000[diff] [blame]779<p>LLVM allows an explicit section to be specified for functions. If the target
780supports it, it will emit functions to the section specified.</p>
781
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]782<p>An explicit alignment may be specified for a function. If not present, or if
783the alignment is set to zero, the alignment of the function is set by the target
784to whatever it feels convenient. If an explicit alignment is specified, the
785function is forced to have at least that much alignment. All alignments must be
786a power of 2.</p>
787
Devang Patel307e8ab2008-10-07 17:48:33 +0000[diff] [blame]788 <h5>Syntax:</h5>
789
790<div class="doc_code">
Chris Lattner50ad45c2008-10-13 16:55:18 +0000[diff] [blame]791<tt>
792define [<a href="#linkage">linkage</a>] [<a href="#visibility">visibility</a>]
793 [<a href="#callingconv">cconv</a>] [<a href="#paramattrs">ret attrs</a>]
794 &lt;ResultType&gt; @&lt;FunctionName&gt; ([argument list])
795 [<a href="#fnattrs">fn Attrs</a>] [section "name"] [align N]
796 [<a href="#gc">gc</a>] { ... }
797</tt>
Devang Patel307e8ab2008-10-07 17:48:33 +0000[diff] [blame]798</div>
799
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]800</div>
801
Anton Korobeynikov8b0a8c82007-04-25 14:27:10 +0000[diff] [blame]802
803<!-- ======================================================================= -->
804<div class="doc_subsection">
805 <a name="aliasstructure">Aliases</a>
806</div>
807<div class="doc_text">
808 <p>Aliases act as "second name" for the aliasee value (which can be either
Anton Korobeynikov726d45c2008-03-22 08:36:14 +0000[diff] [blame]809 function, global variable, another alias or bitcast of global value). Aliases
810 may have an optional <a href="#linkage">linkage type</a>, and an
Anton Korobeynikov8b0a8c82007-04-25 14:27:10 +0000[diff] [blame]811 optional <a href="#visibility">visibility style</a>.</p>
812
813 <h5>Syntax:</h5>
814
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]815<div class="doc_code">
Bill Wendlingaac388b2007-05-29 09:42:13 +0000[diff] [blame]816<pre>
Duncan Sands0b23ac12008-09-12 20:48:21 +0000[diff] [blame]817@&lt;Name&gt; = alias [Linkage] [Visibility] &lt;AliaseeTy&gt; @&lt;Aliasee&gt;
Bill Wendlingaac388b2007-05-29 09:42:13 +0000[diff] [blame]818</pre>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]819</div>
Anton Korobeynikov8b0a8c82007-04-25 14:27:10 +0000[diff] [blame]820
821</div>
822
823
824
Chris Lattner4e9aba72006-01-23 23:23:47 +0000[diff] [blame]825<!-- ======================================================================= -->
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]826<div class="doc_subsection"><a name="paramattrs">Parameter Attributes</a></div>
827<div class="doc_text">
828 <p>The return type and each parameter of a function type may have a set of
829 <i>parameter attributes</i> associated with them. Parameter attributes are
830 used to communicate additional information about the result or parameters of
Duncan Sandsdc024672007-11-27 13:23:08 +0000[diff] [blame]831 a function. Parameter attributes are considered to be part of the function,
832 not of the function type, so functions with different parameter attributes
833 can have the same function type.</p>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]834
Reid Spencer950e9f82007-01-15 18:27:39 +0000[diff] [blame]835 <p>Parameter attributes are simple keywords that follow the type specified. If
836 multiple parameter attributes are needed, they are space separated. For
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]837 example:</p>
838
839<div class="doc_code">
840<pre>
Devang Patel2c9c3e72008-09-26 23:51:19 +0000[diff] [blame]841declare i32 @printf(i8* noalias , ...)
Chris Lattner66d922c2008-10-04 18:33:34 +0000[diff] [blame]842declare i32 @atoi(i8 zeroext)
843declare signext i8 @returns_signed_char()
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]844</pre>
845</div>
846
Duncan Sandsdc024672007-11-27 13:23:08 +0000[diff] [blame]847 <p>Note that any attributes for the function result (<tt>nounwind</tt>,
848 <tt>readonly</tt>) come immediately after the argument list.</p>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]849
Anton Korobeynikov7f705592007-01-12 19:20:47 +0000[diff] [blame]850 <p>Currently, only the following parameter attributes are defined:</p>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]851 <dl>
Reid Spencer9445e9a2007-07-19 23:13:04 +0000[diff] [blame]852 <dt><tt>zeroext</tt></dt>
Chris Lattner66d922c2008-10-04 18:33:34 +0000[diff] [blame]853 <dd>This indicates to the code generator that the parameter or return value
854 should be zero-extended to a 32-bit value by the caller (for a parameter)
855 or the callee (for a return value).</dd>
Chris Lattner47507de2008-01-11 06:20:47 +0000[diff] [blame]856
Reid Spencer9445e9a2007-07-19 23:13:04 +0000[diff] [blame]857 <dt><tt>signext</tt></dt>
Chris Lattner66d922c2008-10-04 18:33:34 +0000[diff] [blame]858 <dd>This indicates to the code generator that the parameter or return value
859 should be sign-extended to a 32-bit value by the caller (for a parameter)
860 or the callee (for a return value).</dd>
Chris Lattner47507de2008-01-11 06:20:47 +0000[diff] [blame]861
Anton Korobeynikov34d6dea2007-01-28 14:30:45 +0000[diff] [blame]862 <dt><tt>inreg</tt></dt>
Dale Johannesenc9c6da62008-09-25 20:47:45 +0000[diff] [blame]863 <dd>This indicates that this parameter or return value should be treated
864 in a special target-dependent fashion during while emitting code for a
865 function call or return (usually, by putting it in a register as opposed
Chris Lattner66d922c2008-10-04 18:33:34 +0000[diff] [blame]866 to memory, though some targets use it to distinguish between two different
867 kinds of registers). Use of this attribute is target-specific.</dd>
Chris Lattner47507de2008-01-11 06:20:47 +0000[diff] [blame]868
Duncan Sandsedb05df2008-10-06 08:14:18 +0000[diff] [blame]869 <dt><tt><a name="byval">byval</a></tt></dt>
Chris Lattner0747baa2008-01-15 04:34:22 +0000[diff] [blame]870 <dd>This indicates that the pointer parameter should really be passed by
871 value to the function. The attribute implies that a hidden copy of the
872 pointee is made between the caller and the callee, so the callee is unable
Chris Lattnerebec6782008-08-05 18:21:08 +0000[diff] [blame]873 to modify the value in the callee. This attribute is only valid on LLVM
Chris Lattner0747baa2008-01-15 04:34:22 +0000[diff] [blame]874 pointer arguments. It is generally used to pass structs and arrays by
Duncan Sandsedb05df2008-10-06 08:14:18 +0000[diff] [blame]875 value, but is also valid on pointers to scalars. The copy is considered to
876 belong to the caller not the callee (for example,
877 <tt><a href="#readonly">readonly</a></tt> functions should not write to
Devang Patelf642f472008-10-06 18:50:38 +0000[diff] [blame]878 <tt>byval</tt> parameters). This is not a valid attribute for return
879 values. </dd>
Chris Lattner47507de2008-01-11 06:20:47 +0000[diff] [blame]880
Anton Korobeynikov34d6dea2007-01-28 14:30:45 +0000[diff] [blame]881 <dt><tt>sret</tt></dt>
Duncan Sandse26dec62008-02-18 04:19:38 +0000[diff] [blame]882 <dd>This indicates that the pointer parameter specifies the address of a
883 structure that is the return value of the function in the source program.
Chris Lattner66d922c2008-10-04 18:33:34 +0000[diff] [blame]884 This pointer must be guaranteed by the caller to be valid: loads and stores
885 to the structure may be assumed by the callee to not to trap. This may only
Devang Patelf642f472008-10-06 18:50:38 +0000[diff] [blame]886 be applied to the first parameter. This is not a valid attribute for
887 return values. </dd>
Chris Lattner47507de2008-01-11 06:20:47 +0000[diff] [blame]888
Zhou Shengfebca342007-06-05 05:28:26 +0000[diff] [blame]889 <dt><tt>noalias</tt></dt>
Owen Anderson117bbd32008-02-18 04:09:01 +0000[diff] [blame]890 <dd>This indicates that the parameter does not alias any global or any other
891 parameter. The caller is responsible for ensuring that this is the case,
Devang Patelf642f472008-10-06 18:50:38 +0000[diff] [blame]892 usually by placing the value in a stack allocation. This is not a valid
893 attribute for return values.</dd>
Chris Lattner47507de2008-01-11 06:20:47 +0000[diff] [blame]894
Duncan Sands50f19f52007-07-27 19:57:41 +0000[diff] [blame]895 <dt><tt>nest</tt></dt>
Duncan Sands0789b8b2008-07-08 09:27:25 +0000[diff] [blame]896 <dd>This indicates that the pointer parameter can be excised using the
Devang Patelf642f472008-10-06 18:50:38 +0000[diff] [blame]897 <a href="#int_trampoline">trampoline intrinsics</a>. This is not a valid
898 attribute for return values.</dd>
Anton Korobeynikov7f705592007-01-12 19:20:47 +0000[diff] [blame]899 </dl>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]900
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]901</div>
902
903<!-- ======================================================================= -->
Chris Lattner4e9aba72006-01-23 23:23:47 +0000[diff] [blame]904<div class="doc_subsection">
Gordon Henriksen80a75bf2007-12-10 03:18:06 +0000[diff] [blame]905 <a name="gc">Garbage Collector Names</a>
906</div>
907
908<div class="doc_text">
909<p>Each function may specify a garbage collector name, which is simply a
910string.</p>
911
912<div class="doc_code"><pre
913>define void @f() gc "name" { ...</pre></div>
914
915<p>The compiler declares the supported values of <i>name</i>. Specifying a
916collector which will cause the compiler to alter its output in order to support
917the named garbage collection algorithm.</p>
918</div>
919
920<!-- ======================================================================= -->
921<div class="doc_subsection">
Devang Patel2c9c3e72008-09-26 23:51:19 +0000[diff] [blame]922 <a name="fnattrs">Function Attributes</a>
Devang Patelf8b94812008-09-04 23:05:13 +0000[diff] [blame]923</div>
924
925<div class="doc_text">
Devang Patel2c9c3e72008-09-26 23:51:19 +0000[diff] [blame]926
927<p>Function attributes are set to communicate additional information about
928 a function. Function attributes are considered to be part of the function,
929 not of the function type, so functions with different parameter attributes
930 can have the same function type.</p>
931
932 <p>Function attributes are simple keywords that follow the type specified. If
933 multiple attributes are needed, they are space separated. For
934 example:</p>
Devang Patelf8b94812008-09-04 23:05:13 +0000[diff] [blame]935
936<div class="doc_code">
Bill Wendlinge36dccc2008-09-07 10:26:33 +0000[diff] [blame]937<pre>
Devang Patel2c9c3e72008-09-26 23:51:19 +0000[diff] [blame]938define void @f() noinline { ... }
939define void @f() alwaysinline { ... }
940define void @f() alwaysinline optsize { ... }
941define void @f() optsize
Bill Wendlinge36dccc2008-09-07 10:26:33 +0000[diff] [blame]942</pre>
Devang Patelf8b94812008-09-04 23:05:13 +0000[diff] [blame]943</div>
944
Bill Wendlinge36dccc2008-09-07 10:26:33 +0000[diff] [blame]945<dl>
Devang Patel2c9c3e72008-09-26 23:51:19 +0000[diff] [blame]946<dt><tt>alwaysinline</tt></dt>
Chris Lattner88d4b592008-10-04 18:23:17 +0000[diff] [blame]947<dd>This attribute indicates that the inliner should attempt to inline this
948function into callers whenever possible, ignoring any active inlining size
949threshold for this caller.</dd>
Bill Wendlinge36dccc2008-09-07 10:26:33 +0000[diff] [blame]950
Devang Patel2c9c3e72008-09-26 23:51:19 +0000[diff] [blame]951<dt><tt>noinline</tt></dt>
Chris Lattner88d4b592008-10-04 18:23:17 +0000[diff] [blame]952<dd>This attribute indicates that the inliner should never inline this function
Chris Lattner94b5f7d2008-10-05 17:14:59 +0000[diff] [blame]953in any situation. This attribute may not be used together with the
Chris Lattner88d4b592008-10-04 18:23:17 +0000[diff] [blame]954<tt>alwaysinline</tt> attribute.</dd>
Bill Wendlinge36dccc2008-09-07 10:26:33 +0000[diff] [blame]955
Devang Patel2c9c3e72008-09-26 23:51:19 +0000[diff] [blame]956<dt><tt>optsize</tt></dt>
Devang Patel66c6c652008-09-29 18:34:44 +0000[diff] [blame]957<dd>This attribute suggests that optimization passes and code generator passes
Chris Lattner88d4b592008-10-04 18:23:17 +0000[diff] [blame]958make choices that keep the code size of this function low, and otherwise do
959optimizations specifically to reduce code size.</dd>
Bill Wendlinge36dccc2008-09-07 10:26:33 +0000[diff] [blame]960
Devang Patel2c9c3e72008-09-26 23:51:19 +0000[diff] [blame]961<dt><tt>noreturn</tt></dt>
Chris Lattner88d4b592008-10-04 18:23:17 +0000[diff] [blame]962<dd>This function attribute indicates that the function never returns normally.
963This produces undefined behavior at runtime if the function ever does
964dynamically return.</dd>
Devang Patel2c9c3e72008-09-26 23:51:19 +0000[diff] [blame]965
966<dt><tt>nounwind</tt></dt>
Chris Lattner88d4b592008-10-04 18:23:17 +0000[diff] [blame]967<dd>This function attribute indicates that the function never returns with an
968unwind or exceptional control flow. If the function does unwind, its runtime
969behavior is undefined.</dd>
970
971<dt><tt>readnone</tt></dt>
Duncan Sandsedb05df2008-10-06 08:14:18 +0000[diff] [blame]972<dd>This attribute indicates that the function computes its result (or the
973exception it throws) based strictly on its arguments, without dereferencing any
974pointer arguments or otherwise accessing any mutable state (e.g. memory, control
975registers, etc) visible to caller functions. It does not write through any
976pointer arguments (including <tt><a href="#byval">byval</a></tt> arguments) and
977never changes any state visible to callers.</dd>
Devang Patel2c9c3e72008-09-26 23:51:19 +0000[diff] [blame]978
Duncan Sandsedb05df2008-10-06 08:14:18 +0000[diff] [blame]979<dt><tt><a name="readonly">readonly</a></tt></dt>
980<dd>This attribute indicates that the function does not write through any
981pointer arguments (including <tt><a href="#byval">byval</a></tt> arguments)
982or otherwise modify any state (e.g. memory, control registers, etc) visible to
983caller functions. It may dereference pointer arguments and read state that may
984be set in the caller. A readonly function always returns the same value (or
985throws the same exception) when called with the same set of arguments and global
986state.</dd>
Bill Wendlinge36dccc2008-09-07 10:26:33 +0000[diff] [blame]987</dl>
988
Devang Patelf8b94812008-09-04 23:05:13 +0000[diff] [blame]989</div>
990
991<!-- ======================================================================= -->
992<div class="doc_subsection">
Chris Lattner1eeeb0c2006-04-08 04:40:53 +0000[diff] [blame]993 <a name="moduleasm">Module-Level Inline Assembly</a>
Chris Lattner4e9aba72006-01-23 23:23:47 +0000[diff] [blame]994</div>
995
996<div class="doc_text">
997<p>
998Modules may contain "module-level inline asm" blocks, which corresponds to the
999GCC "file scope inline asm" blocks. These blocks are internally concatenated by
1000LLVM and treated as a single unit, but may be separated in the .ll file if
1001desired. The syntax is very simple:
1002</p>
1003
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]1004<div class="doc_code">
1005<pre>
1006module asm "inline asm code goes here"
1007module asm "more can go here"
1008</pre>
1009</div>
Chris Lattner4e9aba72006-01-23 23:23:47 +0000[diff] [blame]1010
1011<p>The strings can contain any character by escaping non-printable characters.
1012 The escape sequence used is simply "\xx" where "xx" is the two digit hex code
1013 for the number.
1014</p>
1015
1016<p>
1017 The inline asm code is simply printed to the machine code .s file when
1018 assembly code is generated.
1019</p>
1020</div>
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]1021
Reid Spencerde151942007-02-19 23:54:10 +0000[diff] [blame]1022<!-- ======================================================================= -->
1023<div class="doc_subsection">
1024 <a name="datalayout">Data Layout</a>
1025</div>
1026
1027<div class="doc_text">
1028<p>A module may specify a target specific data layout string that specifies how
Reid Spencerc8910842007-04-11 23:49:50 +0000[diff] [blame]1029data is to be laid out in memory. The syntax for the data layout is simply:</p>
1030<pre> target datalayout = "<i>layout specification</i>"</pre>
1031<p>The <i>layout specification</i> consists of a list of specifications
1032separated by the minus sign character ('-'). Each specification starts with a
1033letter and may include other information after the letter to define some
1034aspect of the data layout. The specifications accepted are as follows: </p>
Reid Spencerde151942007-02-19 23:54:10 +0000[diff] [blame]1035<dl>
1036 <dt><tt>E</tt></dt>
1037 <dd>Specifies that the target lays out data in big-endian form. That is, the
1038 bits with the most significance have the lowest address location.</dd>
1039 <dt><tt>e</tt></dt>
Chris Lattnerd3eda892008-08-05 18:29:16 +0000[diff] [blame]1040 <dd>Specifies that the target lays out data in little-endian form. That is,
Reid Spencerde151942007-02-19 23:54:10 +0000[diff] [blame]1041 the bits with the least significance have the lowest address location.</dd>
1042 <dt><tt>p:<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
1043 <dd>This specifies the <i>size</i> of a pointer and its <i>abi</i> and
1044 <i>preferred</i> alignments. All sizes are in bits. Specifying the <i>pref</i>
1045 alignment is optional. If omitted, the preceding <tt>:</tt> should be omitted
1046 too.</dd>
1047 <dt><tt>i<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
1048 <dd>This specifies the alignment for an integer type of a given bit
1049 <i>size</i>. The value of <i>size</i> must be in the range [1,2^23).</dd>
1050 <dt><tt>v<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
1051 <dd>This specifies the alignment for a vector type of a given bit
1052 <i>size</i>.</dd>
1053 <dt><tt>f<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
1054 <dd>This specifies the alignment for a floating point type of a given bit
1055 <i>size</i>. The value of <i>size</i> must be either 32 (float) or 64
1056 (double).</dd>
1057 <dt><tt>a<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
1058 <dd>This specifies the alignment for an aggregate type of a given bit
1059 <i>size</i>.</dd>
1060</dl>
1061<p>When constructing the data layout for a given target, LLVM starts with a
1062default set of specifications which are then (possibly) overriden by the
1063specifications in the <tt>datalayout</tt> keyword. The default specifications
1064are given in this list:</p>
1065<ul>
1066 <li><tt>E</tt> - big endian</li>
1067 <li><tt>p:32:64:64</tt> - 32-bit pointers with 64-bit alignment</li>
1068 <li><tt>i1:8:8</tt> - i1 is 8-bit (byte) aligned</li>
1069 <li><tt>i8:8:8</tt> - i8 is 8-bit (byte) aligned</li>
1070 <li><tt>i16:16:16</tt> - i16 is 16-bit aligned</li>
1071 <li><tt>i32:32:32</tt> - i32 is 32-bit aligned</li>
Chris Lattnerd3eda892008-08-05 18:29:16 +0000[diff] [blame]1072 <li><tt>i64:32:64</tt> - i64 has ABI alignment of 32-bits but preferred
Reid Spencerde151942007-02-19 23:54:10 +0000[diff] [blame]1073 alignment of 64-bits</li>
1074 <li><tt>f32:32:32</tt> - float is 32-bit aligned</li>
1075 <li><tt>f64:64:64</tt> - double is 64-bit aligned</li>
1076 <li><tt>v64:64:64</tt> - 64-bit vector is 64-bit aligned</li>
1077 <li><tt>v128:128:128</tt> - 128-bit vector is 128-bit aligned</li>
1078 <li><tt>a0:0:1</tt> - aggregates are 8-bit aligned</li>
1079</ul>
Chris Lattnerebec6782008-08-05 18:21:08 +0000[diff] [blame]1080<p>When LLVM is determining the alignment for a given type, it uses the
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]1081following rules:</p>
Reid Spencerde151942007-02-19 23:54:10 +0000[diff] [blame]1082<ol>
1083 <li>If the type sought is an exact match for one of the specifications, that
1084 specification is used.</li>
1085 <li>If no match is found, and the type sought is an integer type, then the
1086 smallest integer type that is larger than the bitwidth of the sought type is
1087 used. If none of the specifications are larger than the bitwidth then the the
1088 largest integer type is used. For example, given the default specifications
1089 above, the i7 type will use the alignment of i8 (next largest) while both
1090 i65 and i256 will use the alignment of i64 (largest specified).</li>
1091 <li>If no match is found, and the type sought is a vector type, then the
1092 largest vector type that is smaller than the sought vector type will be used
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]1093 as a fall back. This happens because &lt;128 x double&gt; can be implemented
1094 in terms of 64 &lt;2 x double&gt;, for example.</li>
Reid Spencerde151942007-02-19 23:54:10 +0000[diff] [blame]1095</ol>
1096</div>
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]1097
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1098<!-- *********************************************************************** -->
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1099<div class="doc_section"> <a name="typesystem">Type System</a> </div>
1100<!-- *********************************************************************** -->
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]1101
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1102<div class="doc_text">
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]1103
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1104<p>The LLVM type system is one of the most important features of the
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1105intermediate representation. Being typed enables a number of
Chris Lattnerd3eda892008-08-05 18:29:16 +0000[diff] [blame]1106optimizations to be performed on the intermediate representation directly,
1107without having to do
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1108extra analyses on the side before the transformation. A strong type
1109system makes it easier to read the generated code and enables novel
1110analyses and transformations that are not feasible to perform on normal
1111three address code representations.</p>
Chris Lattnerfa730212004-12-09 16:11:40 +0000[diff] [blame]1112
1113</div>
1114
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1115<!-- ======================================================================= -->
Chris Lattner4f69f462008-01-04 04:32:38 +0000[diff] [blame]1116<div class="doc_subsection"> <a name="t_classifications">Type
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1117Classifications</a> </div>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1118<div class="doc_text">
Chris Lattner4f69f462008-01-04 04:32:38 +0000[diff] [blame]1119<p>The types fall into a few useful
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1120classifications:</p>
Misha Brukmandaa4cb02004-03-01 17:47:27 +0000[diff] [blame]1121
1122<table border="1" cellspacing="0" cellpadding="4">
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1123 <tbody>
Reid Spencerd3f876c2004-11-01 08:19:36 +0000[diff] [blame]1124 <tr><th>Classification</th><th>Types</th></tr>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1125 <tr>
Chris Lattner4f69f462008-01-04 04:32:38 +0000[diff] [blame]1126 <td><a href="#t_integer">integer</a></td>
Reid Spencer2b916312007-05-16 18:44:01 +0000[diff] [blame]1127 <td><tt>i1, i2, i3, ... i8, ... i16, ... i32, ... i64, ... </tt></td>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1128 </tr>
1129 <tr>
Chris Lattner4f69f462008-01-04 04:32:38 +0000[diff] [blame]1130 <td><a href="#t_floating">floating point</a></td>
1131 <td><tt>float, double, x86_fp80, fp128, ppc_fp128</tt></td>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1132 </tr>
1133 <tr>
1134 <td><a name="t_firstclass">first class</a></td>
Chris Lattner4f69f462008-01-04 04:32:38 +0000[diff] [blame]1135 <td><a href="#t_integer">integer</a>,
1136 <a href="#t_floating">floating point</a>,
1137 <a href="#t_pointer">pointer</a>,
Dan Gohman0066db62008-06-18 18:42:13 +0000[diff] [blame]1138 <a href="#t_vector">vector</a>,
Dan Gohmana334d5f2008-05-12 23:51:09 +0000[diff] [blame]1139 <a href="#t_struct">structure</a>,
1140 <a href="#t_array">array</a>,
Dan Gohmanade5faa2008-05-23 22:50:26 +0000[diff] [blame]1141 <a href="#t_label">label</a>.
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]1142 </td>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1143 </tr>
Chris Lattner4f69f462008-01-04 04:32:38 +0000[diff] [blame]1144 <tr>
1145 <td><a href="#t_primitive">primitive</a></td>
1146 <td><a href="#t_label">label</a>,
1147 <a href="#t_void">void</a>,
Chris Lattner4f69f462008-01-04 04:32:38 +0000[diff] [blame]1148 <a href="#t_floating">floating point</a>.</td>
1149 </tr>
1150 <tr>
1151 <td><a href="#t_derived">derived</a></td>
1152 <td><a href="#t_integer">integer</a>,
1153 <a href="#t_array">array</a>,
1154 <a href="#t_function">function</a>,
1155 <a href="#t_pointer">pointer</a>,
1156 <a href="#t_struct">structure</a>,
1157 <a href="#t_pstruct">packed structure</a>,
1158 <a href="#t_vector">vector</a>,
1159 <a href="#t_opaque">opaque</a>.
Dan Gohman01ac1012008-10-14 16:32:04 +0000[diff] [blame]1160 </td>
Chris Lattner4f69f462008-01-04 04:32:38 +0000[diff] [blame]1161 </tr>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1162 </tbody>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1163</table>
Misha Brukmandaa4cb02004-03-01 17:47:27 +0000[diff] [blame]1164
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1165<p>The <a href="#t_firstclass">first class</a> types are perhaps the
1166most important. Values of these types are the only ones which can be
1167produced by instructions, passed as arguments, or used as operands to
Dan Gohmanc4b49eb2008-05-23 21:53:15 +0000[diff] [blame]1168instructions.</p>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1169</div>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1170
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1171<!-- ======================================================================= -->
Chris Lattner4f69f462008-01-04 04:32:38 +0000[diff] [blame]1172<div class="doc_subsection"> <a name="t_primitive">Primitive Types</a> </div>
Chris Lattner8f8c7b72008-01-04 04:34:14 +0000[diff] [blame]1173
Chris Lattner4f69f462008-01-04 04:32:38 +0000[diff] [blame]1174<div class="doc_text">
1175<p>The primitive types are the fundamental building blocks of the LLVM
1176system.</p>
1177
Chris Lattner8f8c7b72008-01-04 04:34:14 +0000[diff] [blame]1178</div>
1179
Chris Lattner4f69f462008-01-04 04:32:38 +0000[diff] [blame]1180<!-- _______________________________________________________________________ -->
1181<div class="doc_subsubsection"> <a name="t_floating">Floating Point Types</a> </div>
1182
1183<div class="doc_text">
1184 <table>
1185 <tbody>
1186 <tr><th>Type</th><th>Description</th></tr>
1187 <tr><td><tt>float</tt></td><td>32-bit floating point value</td></tr>
1188 <tr><td><tt>double</tt></td><td>64-bit floating point value</td></tr>
1189 <tr><td><tt>fp128</tt></td><td>128-bit floating point value (112-bit mantissa)</td></tr>
1190 <tr><td><tt>x86_fp80</tt></td><td>80-bit floating point value (X87)</td></tr>
1191 <tr><td><tt>ppc_fp128</tt></td><td>128-bit floating point value (two 64-bits)</td></tr>
1192 </tbody>
1193 </table>
1194</div>
1195
1196<!-- _______________________________________________________________________ -->
1197<div class="doc_subsubsection"> <a name="t_void">Void Type</a> </div>
1198
1199<div class="doc_text">
1200<h5>Overview:</h5>
1201<p>The void type does not represent any value and has no size.</p>
1202
1203<h5>Syntax:</h5>
1204
1205<pre>
1206 void
1207</pre>
1208</div>
1209
1210<!-- _______________________________________________________________________ -->
1211<div class="doc_subsubsection"> <a name="t_label">Label Type</a> </div>
1212
1213<div class="doc_text">
1214<h5>Overview:</h5>
1215<p>The label type represents code labels.</p>
1216
1217<h5>Syntax:</h5>
1218
1219<pre>
1220 label
1221</pre>
1222</div>
1223
1224
1225<!-- ======================================================================= -->
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1226<div class="doc_subsection"> <a name="t_derived">Derived Types</a> </div>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1227
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1228<div class="doc_text">
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1229
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1230<p>The real power in LLVM comes from the derived types in the system.
1231This is what allows a programmer to represent arrays, functions,
1232pointers, and other useful types. Note that these derived types may be
1233recursive: For example, it is possible to have a two dimensional array.</p>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1234
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1235</div>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1236
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1237<!-- _______________________________________________________________________ -->
Reid Spencer2b916312007-05-16 18:44:01 +0000[diff] [blame]1238<div class="doc_subsubsection"> <a name="t_integer">Integer Type</a> </div>
1239
1240<div class="doc_text">
1241
1242<h5>Overview:</h5>
1243<p>The integer type is a very simple derived type that simply specifies an
1244arbitrary bit width for the integer type desired. Any bit width from 1 bit to
12452^23-1 (about 8 million) can be specified.</p>
1246
1247<h5>Syntax:</h5>
1248
1249<pre>
1250 iN
1251</pre>
1252
1253<p>The number of bits the integer will occupy is specified by the <tt>N</tt>
1254value.</p>
1255
1256<h5>Examples:</h5>
1257<table class="layout">
Chris Lattnerb9488a62007-12-18 06:18:21 +0000[diff] [blame]1258 <tbody>
1259 <tr>
1260 <td><tt>i1</tt></td>
1261 <td>a single-bit integer.</td>
1262 </tr><tr>
1263 <td><tt>i32</tt></td>
1264 <td>a 32-bit integer.</td>
1265 </tr><tr>
1266 <td><tt>i1942652</tt></td>
1267 <td>a really big integer of over 1 million bits.</td>
Reid Spencer2b916312007-05-16 18:44:01 +0000[diff] [blame]1268 </tr>
Chris Lattnerb9488a62007-12-18 06:18:21 +0000[diff] [blame]1269 </tbody>
Reid Spencer2b916312007-05-16 18:44:01 +0000[diff] [blame]1270</table>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]1271</div>
Reid Spencer2b916312007-05-16 18:44:01 +0000[diff] [blame]1272
1273<!-- _______________________________________________________________________ -->
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1274<div class="doc_subsubsection"> <a name="t_array">Array Type</a> </div>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1275
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1276<div class="doc_text">
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1277
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1278<h5>Overview:</h5>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1279
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1280<p>The array type is a very simple derived type that arranges elements
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1281sequentially in memory. The array type requires a size (number of
1282elements) and an underlying data type.</p>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1283
Chris Lattner7faa8832002-04-14 06:13:44 +0000[diff] [blame]1284<h5>Syntax:</h5>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1285
1286<pre>
1287 [&lt;# elements&gt; x &lt;elementtype&gt;]
1288</pre>
1289
John Criswelle4c57cc2005-05-12 16:52:32 +0000[diff] [blame]1290<p>The number of elements is a constant integer value; elementtype may
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1291be any type with a size.</p>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1292
Chris Lattner7faa8832002-04-14 06:13:44 +0000[diff] [blame]1293<h5>Examples:</h5>
Reid Spencerd3f876c2004-11-01 08:19:36 +0000[diff] [blame]1294<table class="layout">
1295 <tr class="layout">
Chris Lattner23ff1f92007-12-19 05:04:11 +0000[diff] [blame]1296 <td class="left"><tt>[40 x i32]</tt></td>
1297 <td class="left">Array of 40 32-bit integer values.</td>
1298 </tr>
1299 <tr class="layout">
1300 <td class="left"><tt>[41 x i32]</tt></td>
1301 <td class="left">Array of 41 32-bit integer values.</td>
1302 </tr>
1303 <tr class="layout">
1304 <td class="left"><tt>[4 x i8]</tt></td>
1305 <td class="left">Array of 4 8-bit integer values.</td>
Reid Spencerd3f876c2004-11-01 08:19:36 +0000[diff] [blame]1306 </tr>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1307</table>
Reid Spencerd3f876c2004-11-01 08:19:36 +0000[diff] [blame]1308<p>Here are some examples of multidimensional arrays:</p>
1309<table class="layout">
1310 <tr class="layout">
Chris Lattner23ff1f92007-12-19 05:04:11 +0000[diff] [blame]1311 <td class="left"><tt>[3 x [4 x i32]]</tt></td>
1312 <td class="left">3x4 array of 32-bit integer values.</td>
1313 </tr>
1314 <tr class="layout">
1315 <td class="left"><tt>[12 x [10 x float]]</tt></td>
1316 <td class="left">12x10 array of single precision floating point values.</td>
1317 </tr>
1318 <tr class="layout">
1319 <td class="left"><tt>[2 x [3 x [4 x i16]]]</tt></td>
1320 <td class="left">2x3x4 array of 16-bit integer values.</td>
Reid Spencerd3f876c2004-11-01 08:19:36 +0000[diff] [blame]1321 </tr>
1322</table>
Chris Lattnere67a9512005-06-24 17:22:57 +0000[diff] [blame]1323
John Criswell0ec250c2005-10-24 16:17:18 +0000[diff] [blame]1324<p>Note that 'variable sized arrays' can be implemented in LLVM with a zero
1325length array. Normally, accesses past the end of an array are undefined in
Chris Lattnere67a9512005-06-24 17:22:57 +0000[diff] [blame]1326LLVM (e.g. it is illegal to access the 5th element of a 3 element array).
1327As a special case, however, zero length arrays are recognized to be variable
1328length. This allows implementation of 'pascal style arrays' with the LLVM
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]1329type "{ i32, [0 x float]}", for example.</p>
Chris Lattnere67a9512005-06-24 17:22:57 +0000[diff] [blame]1330
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1331</div>
Reid Spencerd3f876c2004-11-01 08:19:36 +0000[diff] [blame]1332
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1333<!-- _______________________________________________________________________ -->
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1334<div class="doc_subsubsection"> <a name="t_function">Function Type</a> </div>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1335<div class="doc_text">
Chris Lattnerf4cde4e2008-04-23 04:59:35 +0000[diff] [blame]1336
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1337<h5>Overview:</h5>
Chris Lattnerf4cde4e2008-04-23 04:59:35 +0000[diff] [blame]1338
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1339<p>The function type can be thought of as a function signature. It
Devang Patela582f402008-03-24 05:35:41 +0000[diff] [blame]1340consists of a return type and a list of formal parameter types. The
Chris Lattnerf4cde4e2008-04-23 04:59:35 +0000[diff] [blame]1341return type of a function type is a scalar type, a void type, or a struct type.
Devang Patel7a3ad1a2008-03-24 20:52:42 +0000[diff] [blame]1342If the return type is a struct type then all struct elements must be of first
Chris Lattnerf4cde4e2008-04-23 04:59:35 +0000[diff] [blame]1343class types, and the struct must have at least one element.</p>
Devang Patelc3fc6df2008-03-10 20:49:15 +0000[diff] [blame]1344
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1345<h5>Syntax:</h5>
Chris Lattnerf4cde4e2008-04-23 04:59:35 +0000[diff] [blame]1346
1347<pre>
1348 &lt;returntype list&gt; (&lt;parameter list&gt;)
1349</pre>
1350
John Criswell0ec250c2005-10-24 16:17:18 +0000[diff] [blame]1351<p>...where '<tt>&lt;parameter list&gt;</tt>' is a comma-separated list of type
Misha Brukmanc24b7582004-08-12 20:16:08 +0000[diff] [blame]1352specifiers. Optionally, the parameter list may include a type <tt>...</tt>,
Chris Lattner27f71f22003-09-03 00:41:47 +0000[diff] [blame]1353which indicates that the function takes a variable number of arguments.
1354Variable argument functions can access their arguments with the <a
Devang Patelc3fc6df2008-03-10 20:49:15 +0000[diff] [blame]1355 href="#int_varargs">variable argument handling intrinsic</a> functions.
1356'<tt>&lt;returntype list&gt;</tt>' is a comma-separated list of
1357<a href="#t_firstclass">first class</a> type specifiers.</p>
Chris Lattnerf4cde4e2008-04-23 04:59:35 +0000[diff] [blame]1358
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1359<h5>Examples:</h5>
Reid Spencerd3f876c2004-11-01 08:19:36 +0000[diff] [blame]1360<table class="layout">
1361 <tr class="layout">
Reid Spencer92f82302006-12-31 07:18:34 +0000[diff] [blame]1362 <td class="left"><tt>i32 (i32)</tt></td>
1363 <td class="left">function taking an <tt>i32</tt>, returning an <tt>i32</tt>
Reid Spencerd3f876c2004-11-01 08:19:36 +0000[diff] [blame]1364 </td>
Reid Spencer92f82302006-12-31 07:18:34 +0000[diff] [blame]1365 </tr><tr class="layout">
Reid Spencer9445e9a2007-07-19 23:13:04 +0000[diff] [blame]1366 <td class="left"><tt>float&nbsp;(i16&nbsp;signext,&nbsp;i32&nbsp;*)&nbsp;*
Reid Spencerf17a0b72006-12-31 07:20:23 +0000[diff] [blame]1367 </tt></td>
Reid Spencer92f82302006-12-31 07:18:34 +0000[diff] [blame]1368 <td class="left"><a href="#t_pointer">Pointer</a> to a function that takes
1369 an <tt>i16</tt> that should be sign extended and a
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]1370 <a href="#t_pointer">pointer</a> to <tt>i32</tt>, returning
Reid Spencer92f82302006-12-31 07:18:34 +0000[diff] [blame]1371 <tt>float</tt>.
1372 </td>
1373 </tr><tr class="layout">
1374 <td class="left"><tt>i32 (i8*, ...)</tt></td>
1375 <td class="left">A vararg function that takes at least one
Reid Spencera5173382007-01-04 16:43:23 +0000[diff] [blame]1376 <a href="#t_pointer">pointer</a> to <tt>i8 </tt> (char in C),
Reid Spencer92f82302006-12-31 07:18:34 +0000[diff] [blame]1377 which returns an integer. This is the signature for <tt>printf</tt> in
1378 LLVM.
Reid Spencerd3f876c2004-11-01 08:19:36 +0000[diff] [blame]1379 </td>
Devang Patela582f402008-03-24 05:35:41 +0000[diff] [blame]1380 </tr><tr class="layout">
1381 <td class="left"><tt>{i32, i32} (i32)</tt></td>
Devang Patel3a5bff82008-03-24 18:10:52 +0000[diff] [blame]1382 <td class="left">A function taking an <tt>i32></tt>, returning two
1383 <tt> i32 </tt> values as an aggregate of type <tt>{ i32, i32 }</tt>
Devang Patela582f402008-03-24 05:35:41 +0000[diff] [blame]1384 </td>
Reid Spencerd3f876c2004-11-01 08:19:36 +0000[diff] [blame]1385 </tr>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1386</table>
Misha Brukmandaa4cb02004-03-01 17:47:27 +0000[diff] [blame]1387
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1388</div>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1389<!-- _______________________________________________________________________ -->
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1390<div class="doc_subsubsection"> <a name="t_struct">Structure Type</a> </div>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1391<div class="doc_text">
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1392<h5>Overview:</h5>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1393<p>The structure type is used to represent a collection of data members
1394together in memory. The packing of the field types is defined to match
1395the ABI of the underlying processor. The elements of a structure may
1396be any type that has a size.</p>
1397<p>Structures are accessed using '<tt><a href="#i_load">load</a></tt>
1398and '<tt><a href="#i_store">store</a></tt>' by getting a pointer to a
1399field with the '<tt><a href="#i_getelementptr">getelementptr</a></tt>'
1400instruction.</p>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1401<h5>Syntax:</h5>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1402<pre> { &lt;type list&gt; }<br></pre>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1403<h5>Examples:</h5>
Reid Spencerd3f876c2004-11-01 08:19:36 +0000[diff] [blame]1404<table class="layout">
1405 <tr class="layout">
Jeff Cohen6f1cc772007-04-22 01:17:39 +0000[diff] [blame]1406 <td class="left"><tt>{ i32, i32, i32 }</tt></td>
1407 <td class="left">A triple of three <tt>i32</tt> values</td>
1408 </tr><tr class="layout">
1409 <td class="left"><tt>{&nbsp;float,&nbsp;i32&nbsp;(i32)&nbsp;*&nbsp;}</tt></td>
1410 <td class="left">A pair, where the first element is a <tt>float</tt> and the
1411 second element is a <a href="#t_pointer">pointer</a> to a
1412 <a href="#t_function">function</a> that takes an <tt>i32</tt>, returning
1413 an <tt>i32</tt>.</td>
Reid Spencerd3f876c2004-11-01 08:19:36 +0000[diff] [blame]1414 </tr>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1415</table>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1416</div>
Reid Spencerd3f876c2004-11-01 08:19:36 +0000[diff] [blame]1417
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1418<!-- _______________________________________________________________________ -->
Andrew Lenharth75e10682006-12-08 17:13:00 +0000[diff] [blame]1419<div class="doc_subsubsection"> <a name="t_pstruct">Packed Structure Type</a>
1420</div>
1421<div class="doc_text">
1422<h5>Overview:</h5>
1423<p>The packed structure type is used to represent a collection of data members
1424together in memory. There is no padding between fields. Further, the alignment
1425of a packed structure is 1 byte. The elements of a packed structure may
1426be any type that has a size.</p>
1427<p>Structures are accessed using '<tt><a href="#i_load">load</a></tt>
1428and '<tt><a href="#i_store">store</a></tt>' by getting a pointer to a
1429field with the '<tt><a href="#i_getelementptr">getelementptr</a></tt>'
1430instruction.</p>
1431<h5>Syntax:</h5>
1432<pre> &lt; { &lt;type list&gt; } &gt; <br></pre>
1433<h5>Examples:</h5>
1434<table class="layout">
1435 <tr class="layout">
Jeff Cohen6f1cc772007-04-22 01:17:39 +0000[diff] [blame]1436 <td class="left"><tt>&lt; { i32, i32, i32 } &gt;</tt></td>
1437 <td class="left">A triple of three <tt>i32</tt> values</td>
1438 </tr><tr class="layout">
Bill Wendlinge36dccc2008-09-07 10:26:33 +0000[diff] [blame]1439 <td class="left">
1440<tt>&lt;&nbsp;{&nbsp;float,&nbsp;i32&nbsp;(i32)*&nbsp;}&nbsp;&gt;</tt></td>
Jeff Cohen6f1cc772007-04-22 01:17:39 +0000[diff] [blame]1441 <td class="left">A pair, where the first element is a <tt>float</tt> and the
1442 second element is a <a href="#t_pointer">pointer</a> to a
1443 <a href="#t_function">function</a> that takes an <tt>i32</tt>, returning
1444 an <tt>i32</tt>.</td>
Andrew Lenharth75e10682006-12-08 17:13:00 +0000[diff] [blame]1445 </tr>
1446</table>
1447</div>
1448
1449<!-- _______________________________________________________________________ -->
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1450<div class="doc_subsubsection"> <a name="t_pointer">Pointer Type</a> </div>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1451<div class="doc_text">
Chris Lattner7faa8832002-04-14 06:13:44 +0000[diff] [blame]1452<h5>Overview:</h5>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1453<p>As in many languages, the pointer type represents a pointer or
Christopher Lamb284d9922007-12-11 09:31:00 +0000[diff] [blame]1454reference to another object, which must live in memory. Pointer types may have
1455an optional address space attribute defining the target-specific numbered
1456address space where the pointed-to object resides. The default address space is
1457zero.</p>
Chris Lattner7faa8832002-04-14 06:13:44 +0000[diff] [blame]1458<h5>Syntax:</h5>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1459<pre> &lt;type&gt; *<br></pre>
Chris Lattner7faa8832002-04-14 06:13:44 +0000[diff] [blame]1460<h5>Examples:</h5>
Reid Spencerd3f876c2004-11-01 08:19:36 +0000[diff] [blame]1461<table class="layout">
1462 <tr class="layout">
Chris Lattner23ff1f92007-12-19 05:04:11 +0000[diff] [blame]1463 <td class="left"><tt>[4x i32]*</tt></td>
1464 <td class="left">A <a href="#t_pointer">pointer</a> to <a
1465 href="#t_array">array</a> of four <tt>i32</tt> values.</td>
1466 </tr>
1467 <tr class="layout">
1468 <td class="left"><tt>i32 (i32 *) *</tt></td>
1469 <td class="left"> A <a href="#t_pointer">pointer</a> to a <a
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]1470 href="#t_function">function</a> that takes an <tt>i32*</tt>, returning an
Chris Lattner23ff1f92007-12-19 05:04:11 +0000[diff] [blame]1471 <tt>i32</tt>.</td>
1472 </tr>
1473 <tr class="layout">
1474 <td class="left"><tt>i32 addrspace(5)*</tt></td>
1475 <td class="left">A <a href="#t_pointer">pointer</a> to an <tt>i32</tt> value
1476 that resides in address space #5.</td>
Reid Spencerd3f876c2004-11-01 08:19:36 +0000[diff] [blame]1477 </tr>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1478</table>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1479</div>
Reid Spencerd3f876c2004-11-01 08:19:36 +0000[diff] [blame]1480
Chris Lattnera58561b2004-08-12 19:12:28 +0000[diff] [blame]1481<!-- _______________________________________________________________________ -->
Reid Spencer485bad12007-02-15 03:07:05 +0000[diff] [blame]1482<div class="doc_subsubsection"> <a name="t_vector">Vector Type</a> </div>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1483<div class="doc_text">
Chris Lattner69c11bb2005-04-25 17:34:15 +0000[diff] [blame]1484
Chris Lattnera58561b2004-08-12 19:12:28 +0000[diff] [blame]1485<h5>Overview:</h5>
Chris Lattner69c11bb2005-04-25 17:34:15 +0000[diff] [blame]1486
Reid Spencer485bad12007-02-15 03:07:05 +0000[diff] [blame]1487<p>A vector type is a simple derived type that represents a vector
1488of elements. Vector types are used when multiple primitive data
Chris Lattnera58561b2004-08-12 19:12:28 +0000[diff] [blame]1489are operated in parallel using a single instruction (SIMD).
Reid Spencer485bad12007-02-15 03:07:05 +0000[diff] [blame]1490A vector type requires a size (number of
Chris Lattnerb8d172f2005-11-10 01:44:22 +0000[diff] [blame]1491elements) and an underlying primitive data type. Vectors must have a power
Reid Spencer485bad12007-02-15 03:07:05 +0000[diff] [blame]1492of two length (1, 2, 4, 8, 16 ...). Vector types are
Chris Lattnera58561b2004-08-12 19:12:28 +0000[diff] [blame]1493considered <a href="#t_firstclass">first class</a>.</p>
Chris Lattner69c11bb2005-04-25 17:34:15 +0000[diff] [blame]1494
Chris Lattnera58561b2004-08-12 19:12:28 +0000[diff] [blame]1495<h5>Syntax:</h5>
Chris Lattner69c11bb2005-04-25 17:34:15 +0000[diff] [blame]1496
1497<pre>
1498 &lt; &lt;# elements&gt; x &lt;elementtype&gt; &gt;
1499</pre>
1500
John Criswellc1f786c2005-05-13 22:25:59 +0000[diff] [blame]1501<p>The number of elements is a constant integer value; elementtype may
Chris Lattner3b19d652007-01-15 01:54:13 +0000[diff] [blame]1502be any integer or floating point type.</p>
Chris Lattner69c11bb2005-04-25 17:34:15 +0000[diff] [blame]1503
Chris Lattnera58561b2004-08-12 19:12:28 +0000[diff] [blame]1504<h5>Examples:</h5>
Chris Lattner69c11bb2005-04-25 17:34:15 +0000[diff] [blame]1505
Reid Spencerd3f876c2004-11-01 08:19:36 +0000[diff] [blame]1506<table class="layout">
1507 <tr class="layout">
Chris Lattner23ff1f92007-12-19 05:04:11 +0000[diff] [blame]1508 <td class="left"><tt>&lt;4 x i32&gt;</tt></td>
1509 <td class="left">Vector of 4 32-bit integer values.</td>
1510 </tr>
1511 <tr class="layout">
1512 <td class="left"><tt>&lt;8 x float&gt;</tt></td>
1513 <td class="left">Vector of 8 32-bit floating-point values.</td>
1514 </tr>
1515 <tr class="layout">
1516 <td class="left"><tt>&lt;2 x i64&gt;</tt></td>
1517 <td class="left">Vector of 2 64-bit integer values.</td>
Reid Spencerd3f876c2004-11-01 08:19:36 +0000[diff] [blame]1518 </tr>
1519</table>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1520</div>
1521
Chris Lattner69c11bb2005-04-25 17:34:15 +0000[diff] [blame]1522<!-- _______________________________________________________________________ -->
1523<div class="doc_subsubsection"> <a name="t_opaque">Opaque Type</a> </div>
1524<div class="doc_text">
1525
1526<h5>Overview:</h5>
1527
1528<p>Opaque types are used to represent unknown types in the system. This
Gordon Henriksen8ac04ff2007-10-14 00:34:53 +0000[diff] [blame]1529corresponds (for example) to the C notion of a forward declared structure type.
Chris Lattner69c11bb2005-04-25 17:34:15 +0000[diff] [blame]1530In LLVM, opaque types can eventually be resolved to any type (not just a
1531structure type).</p>
1532
1533<h5>Syntax:</h5>
1534
1535<pre>
1536 opaque
1537</pre>
1538
1539<h5>Examples:</h5>
1540
1541<table class="layout">
1542 <tr class="layout">
Chris Lattner23ff1f92007-12-19 05:04:11 +0000[diff] [blame]1543 <td class="left"><tt>opaque</tt></td>
1544 <td class="left">An opaque type.</td>
Chris Lattner69c11bb2005-04-25 17:34:15 +0000[diff] [blame]1545 </tr>
1546</table>
1547</div>
1548
1549
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1550<!-- *********************************************************************** -->
1551<div class="doc_section"> <a name="constants">Constants</a> </div>
1552<!-- *********************************************************************** -->
1553
1554<div class="doc_text">
1555
1556<p>LLVM has several different basic types of constants. This section describes
1557them all and their syntax.</p>
1558
1559</div>
1560
1561<!-- ======================================================================= -->
Reid Spencercc16dc32004-12-09 18:02:53 +0000[diff] [blame]1562<div class="doc_subsection"><a name="simpleconstants">Simple Constants</a></div>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1563
1564<div class="doc_text">
1565
1566<dl>
1567 <dt><b>Boolean constants</b></dt>
1568
1569 <dd>The two strings '<tt>true</tt>' and '<tt>false</tt>' are both valid
Reid Spencerc78f3372007-01-12 03:35:51 +0000[diff] [blame]1570 constants of the <tt><a href="#t_primitive">i1</a></tt> type.
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1571 </dd>
1572
1573 <dt><b>Integer constants</b></dt>
1574
Reid Spencercc16dc32004-12-09 18:02:53 +0000[diff] [blame]1575 <dd>Standard integers (such as '4') are constants of the <a
Reid Spencera5173382007-01-04 16:43:23 +0000[diff] [blame]1576 href="#t_integer">integer</a> type. Negative numbers may be used with
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1577 integer types.
1578 </dd>
1579
1580 <dt><b>Floating point constants</b></dt>
1581
1582 <dd>Floating point constants use standard decimal notation (e.g. 123.421),
1583 exponential notation (e.g. 1.23421e+2), or a more precise hexadecimal
Chris Lattnera73afe02008-04-01 18:45:27 +0000[diff] [blame]1584 notation (see below). The assembler requires the exact decimal value of
1585 a floating-point constant. For example, the assembler accepts 1.25 but
1586 rejects 1.3 because 1.3 is a repeating decimal in binary. Floating point
1587 constants must have a <a href="#t_floating">floating point</a> type. </dd>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1588
1589 <dt><b>Null pointer constants</b></dt>
1590
John Criswell9e2485c2004-12-10 15:51:16 +0000[diff] [blame]1591 <dd>The identifier '<tt>null</tt>' is recognized as a null pointer constant
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1592 and must be of <a href="#t_pointer">pointer type</a>.</dd>
1593
1594</dl>
1595
John Criswell9e2485c2004-12-10 15:51:16 +0000[diff] [blame]1596<p>The one non-intuitive notation for constants is the optional hexadecimal form
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1597of floating point constants. For example, the form '<tt>double
15980x432ff973cafa8000</tt>' is equivalent to (but harder to read than) '<tt>double
15994.5e+15</tt>'. The only time hexadecimal floating point constants are required
Reid Spencercc16dc32004-12-09 18:02:53 +0000[diff] [blame]1600(and the only time that they are generated by the disassembler) is when a
1601floating point constant must be emitted but it cannot be represented as a
1602decimal floating point number. For example, NaN's, infinities, and other
1603special values are represented in their IEEE hexadecimal format so that
1604assembly and disassembly do not cause any bits to change in the constants.</p>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1605
1606</div>
1607
1608<!-- ======================================================================= -->
1609<div class="doc_subsection"><a name="aggregateconstants">Aggregate Constants</a>
1610</div>
1611
1612<div class="doc_text">
Chris Lattnerd4f6b172005-03-07 22:13:59 +0000[diff] [blame]1613<p>Aggregate constants arise from aggregation of simple constants
1614and smaller aggregate constants.</p>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1615
1616<dl>
1617 <dt><b>Structure constants</b></dt>
1618
1619 <dd>Structure constants are represented with notation similar to structure
1620 type definitions (a comma separated list of elements, surrounded by braces
Chris Lattner64910ee2007-12-25 20:34:52 +0000[diff] [blame]1621 (<tt>{}</tt>)). For example: "<tt>{ i32 4, float 17.0, i32* @G }</tt>",
1622 where "<tt>@G</tt>" is declared as "<tt>@G = external global i32</tt>". Structure constants
Chris Lattnerd4f6b172005-03-07 22:13:59 +0000[diff] [blame]1623 must have <a href="#t_struct">structure type</a>, and the number and
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1624 types of elements must match those specified by the type.
1625 </dd>
1626
1627 <dt><b>Array constants</b></dt>
1628
1629 <dd>Array constants are represented with notation similar to array type
1630 definitions (a comma separated list of elements, surrounded by square brackets
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]1631 (<tt>[]</tt>)). For example: "<tt>[ i32 42, i32 11, i32 74 ]</tt>". Array
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1632 constants must have <a href="#t_array">array type</a>, and the number and
1633 types of elements must match those specified by the type.
1634 </dd>
1635
Reid Spencer485bad12007-02-15 03:07:05 +0000[diff] [blame]1636 <dt><b>Vector constants</b></dt>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1637
Reid Spencer485bad12007-02-15 03:07:05 +0000[diff] [blame]1638 <dd>Vector constants are represented with notation similar to vector type
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1639 definitions (a comma separated list of elements, surrounded by
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]1640 less-than/greater-than's (<tt>&lt;&gt;</tt>)). For example: "<tt>&lt; i32 42,
Jeff Cohen6f1cc772007-04-22 01:17:39 +0000[diff] [blame]1641 i32 11, i32 74, i32 100 &gt;</tt>". Vector constants must have <a
Reid Spencer485bad12007-02-15 03:07:05 +0000[diff] [blame]1642 href="#t_vector">vector type</a>, and the number and types of elements must
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1643 match those specified by the type.
1644 </dd>
1645
1646 <dt><b>Zero initialization</b></dt>
1647
1648 <dd>The string '<tt>zeroinitializer</tt>' can be used to zero initialize a
1649 value to zero of <em>any</em> type, including scalar and aggregate types.
1650 This is often used to avoid having to print large zero initializers (e.g. for
John Criswell0ec250c2005-10-24 16:17:18 +0000[diff] [blame]1651 large arrays) and is always exactly equivalent to using explicit zero
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1652 initializers.
1653 </dd>
1654</dl>
1655
1656</div>
1657
1658<!-- ======================================================================= -->
1659<div class="doc_subsection">
1660 <a name="globalconstants">Global Variable and Function Addresses</a>
1661</div>
1662
1663<div class="doc_text">
1664
1665<p>The addresses of <a href="#globalvars">global variables</a> and <a
1666href="#functionstructure">functions</a> are always implicitly valid (link-time)
John Criswell9e2485c2004-12-10 15:51:16 +0000[diff] [blame]1667constants. These constants are explicitly referenced when the <a
1668href="#identifiers">identifier for the global</a> is used and always have <a
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1669href="#t_pointer">pointer</a> type. For example, the following is a legal LLVM
1670file:</p>
1671
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]1672<div class="doc_code">
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1673<pre>
Chris Lattnera18a4242007-06-06 18:28:13 +0000[diff] [blame]1674@X = global i32 17
1675@Y = global i32 42
1676@Z = global [2 x i32*] [ i32* @X, i32* @Y ]
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1677</pre>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]1678</div>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1679
1680</div>
1681
1682<!-- ======================================================================= -->
Reid Spencer2dc45b82004-12-09 18:13:12 +0000[diff] [blame]1683<div class="doc_subsection"><a name="undefvalues">Undefined Values</a></div>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1684<div class="doc_text">
Reid Spencer2dc45b82004-12-09 18:13:12 +0000[diff] [blame]1685 <p>The string '<tt>undef</tt>' is recognized as a type-less constant that has
John Criswellc1f786c2005-05-13 22:25:59 +0000[diff] [blame]1686 no specific value. Undefined values may be of any type and be used anywhere
Reid Spencer2dc45b82004-12-09 18:13:12 +0000[diff] [blame]1687 a constant is permitted.</p>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1688
Reid Spencer2dc45b82004-12-09 18:13:12 +0000[diff] [blame]1689 <p>Undefined values indicate to the compiler that the program is well defined
1690 no matter what value is used, giving the compiler more freedom to optimize.
1691 </p>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1692</div>
1693
1694<!-- ======================================================================= -->
1695<div class="doc_subsection"><a name="constantexprs">Constant Expressions</a>
1696</div>
1697
1698<div class="doc_text">
1699
1700<p>Constant expressions are used to allow expressions involving other constants
1701to be used as constants. Constant expressions may be of any <a
John Criswellc1f786c2005-05-13 22:25:59 +0000[diff] [blame]1702href="#t_firstclass">first class</a> type and may involve any LLVM operation
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1703that does not have side effects (e.g. load and call are not supported). The
1704following is the syntax for constant expressions:</p>
1705
1706<dl>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]1707 <dt><b><tt>trunc ( CST to TYPE )</tt></b></dt>
1708 <dd>Truncate a constant to another type. The bit size of CST must be larger
Chris Lattner3b19d652007-01-15 01:54:13 +0000[diff] [blame]1709 than the bit size of TYPE. Both types must be integers.</dd>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1710
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]1711 <dt><b><tt>zext ( CST to TYPE )</tt></b></dt>
1712 <dd>Zero extend a constant to another type. The bit size of CST must be
Chris Lattner3b19d652007-01-15 01:54:13 +0000[diff] [blame]1713 smaller or equal to the bit size of TYPE. Both types must be integers.</dd>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]1714
1715 <dt><b><tt>sext ( CST to TYPE )</tt></b></dt>
1716 <dd>Sign extend a constant to another type. The bit size of CST must be
Chris Lattner3b19d652007-01-15 01:54:13 +0000[diff] [blame]1717 smaller or equal to the bit size of TYPE. Both types must be integers.</dd>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]1718
1719 <dt><b><tt>fptrunc ( CST to TYPE )</tt></b></dt>
1720 <dd>Truncate a floating point constant to another floating point type. The
1721 size of CST must be larger than the size of TYPE. Both types must be
1722 floating point.</dd>
1723
1724 <dt><b><tt>fpext ( CST to TYPE )</tt></b></dt>
1725 <dd>Floating point extend a constant to another type. The size of CST must be
1726 smaller or equal to the size of TYPE. Both types must be floating point.</dd>
1727
Reid Spencer1539a1c2007-07-31 14:40:14 +0000[diff] [blame]1728 <dt><b><tt>fptoui ( CST to TYPE )</tt></b></dt>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]1729 <dd>Convert a floating point constant to the corresponding unsigned integer
Nate Begemanb348d182007-11-17 03:58:34 +0000[diff] [blame]1730 constant. TYPE must be a scalar or vector integer type. CST must be of scalar
1731 or vector floating point type. Both CST and TYPE must be scalars, or vectors
1732 of the same number of elements. If the value won't fit in the integer type,
1733 the results are undefined.</dd>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]1734
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]1735 <dt><b><tt>fptosi ( CST to TYPE )</tt></b></dt>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]1736 <dd>Convert a floating point constant to the corresponding signed integer
Nate Begemanb348d182007-11-17 03:58:34 +0000[diff] [blame]1737 constant. TYPE must be a scalar or vector integer type. CST must be of scalar
1738 or vector floating point type. Both CST and TYPE must be scalars, or vectors
1739 of the same number of elements. If the value won't fit in the integer type,
1740 the results are undefined.</dd>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]1741
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]1742 <dt><b><tt>uitofp ( CST to TYPE )</tt></b></dt>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]1743 <dd>Convert an unsigned integer constant to the corresponding floating point
Nate Begemanb348d182007-11-17 03:58:34 +0000[diff] [blame]1744 constant. TYPE must be a scalar or vector floating point type. CST must be of
1745 scalar or vector integer type. Both CST and TYPE must be scalars, or vectors
1746 of the same number of elements. If the value won't fit in the floating point
1747 type, the results are undefined.</dd>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]1748
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]1749 <dt><b><tt>sitofp ( CST to TYPE )</tt></b></dt>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]1750 <dd>Convert a signed integer constant to the corresponding floating point
Nate Begemanb348d182007-11-17 03:58:34 +0000[diff] [blame]1751 constant. TYPE must be a scalar or vector floating point type. CST must be of
1752 scalar or vector integer type. Both CST and TYPE must be scalars, or vectors
1753 of the same number of elements. If the value won't fit in the floating point
1754 type, the results are undefined.</dd>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]1755
Reid Spencer5c0ef472006-11-11 23:08:07 +0000[diff] [blame]1756 <dt><b><tt>ptrtoint ( CST to TYPE )</tt></b></dt>
1757 <dd>Convert a pointer typed constant to the corresponding integer constant
1758 TYPE must be an integer type. CST must be of pointer type. The CST value is
1759 zero extended, truncated, or unchanged to make it fit in TYPE.</dd>
1760
1761 <dt><b><tt>inttoptr ( CST to TYPE )</tt></b></dt>
1762 <dd>Convert a integer constant to a pointer constant. TYPE must be a
1763 pointer type. CST must be of integer type. The CST value is zero extended,
1764 truncated, or unchanged to make it fit in a pointer size. This one is
1765 <i>really</i> dangerous!</dd>
1766
1767 <dt><b><tt>bitcast ( CST to TYPE )</tt></b></dt>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]1768 <dd>Convert a constant, CST, to another TYPE. The size of CST and TYPE must be
1769 identical (same number of bits). The conversion is done as if the CST value
1770 was stored to memory and read back as TYPE. In other words, no bits change
Reid Spencer5c0ef472006-11-11 23:08:07 +0000[diff] [blame]1771 with this operator, just the type. This can be used for conversion of
Reid Spencer485bad12007-02-15 03:07:05 +0000[diff] [blame]1772 vector types to any other type, as long as they have the same bit width. For
Dan Gohman500233a2008-09-08 16:45:59 +0000[diff] [blame]1773 pointers it is only valid to cast to another pointer type. It is not valid
1774 to bitcast to or from an aggregate type.
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]1775 </dd>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1776
1777 <dt><b><tt>getelementptr ( CSTPTR, IDX0, IDX1, ... )</tt></b></dt>
1778
1779 <dd>Perform the <a href="#i_getelementptr">getelementptr operation</a> on
1780 constants. As with the <a href="#i_getelementptr">getelementptr</a>
1781 instruction, the index list may have zero or more indexes, which are required
1782 to make sense for the type of "CSTPTR".</dd>
1783
Robert Bocchino9fbe1452006-01-10 19:31:34 +0000[diff] [blame]1784 <dt><b><tt>select ( COND, VAL1, VAL2 )</tt></b></dt>
1785
1786 <dd>Perform the <a href="#i_select">select operation</a> on
Reid Spencer01c42592006-12-04 19:23:19 +0000[diff] [blame]1787 constants.</dd>
1788
1789 <dt><b><tt>icmp COND ( VAL1, VAL2 )</tt></b></dt>
1790 <dd>Performs the <a href="#i_icmp">icmp operation</a> on constants.</dd>
1791
1792 <dt><b><tt>fcmp COND ( VAL1, VAL2 )</tt></b></dt>
1793 <dd>Performs the <a href="#i_fcmp">fcmp operation</a> on constants.</dd>
Robert Bocchino9fbe1452006-01-10 19:31:34 +0000[diff] [blame]1794
Nate Begemanac80ade2008-05-12 19:01:56 +0000[diff] [blame]1795 <dt><b><tt>vicmp COND ( VAL1, VAL2 )</tt></b></dt>
1796 <dd>Performs the <a href="#i_vicmp">vicmp operation</a> on constants.</dd>
1797
1798 <dt><b><tt>vfcmp COND ( VAL1, VAL2 )</tt></b></dt>
1799 <dd>Performs the <a href="#i_vfcmp">vfcmp operation</a> on constants.</dd>
1800
Robert Bocchino9fbe1452006-01-10 19:31:34 +0000[diff] [blame]1801 <dt><b><tt>extractelement ( VAL, IDX )</tt></b></dt>
1802
1803 <dd>Perform the <a href="#i_extractelement">extractelement
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]1804 operation</a> on constants.</dd>
Robert Bocchino9fbe1452006-01-10 19:31:34 +0000[diff] [blame]1805
Robert Bocchino05ccd702006-01-15 20:48:27 +0000[diff] [blame]1806 <dt><b><tt>insertelement ( VAL, ELT, IDX )</tt></b></dt>
1807
1808 <dd>Perform the <a href="#i_insertelement">insertelement
Reid Spencer01c42592006-12-04 19:23:19 +0000[diff] [blame]1809 operation</a> on constants.</dd>
Robert Bocchino05ccd702006-01-15 20:48:27 +0000[diff] [blame]1810
Chris Lattnerc1989542006-04-08 00:13:41 +0000[diff] [blame]1811
1812 <dt><b><tt>shufflevector ( VEC1, VEC2, IDXMASK )</tt></b></dt>
1813
1814 <dd>Perform the <a href="#i_shufflevector">shufflevector
Reid Spencer01c42592006-12-04 19:23:19 +0000[diff] [blame]1815 operation</a> on constants.</dd>
Chris Lattnerc1989542006-04-08 00:13:41 +0000[diff] [blame]1816
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1817 <dt><b><tt>OPCODE ( LHS, RHS )</tt></b></dt>
1818
Reid Spencer2dc45b82004-12-09 18:13:12 +0000[diff] [blame]1819 <dd>Perform the specified operation of the LHS and RHS constants. OPCODE may
1820 be any of the <a href="#binaryops">binary</a> or <a href="#bitwiseops">bitwise
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1821 binary</a> operations. The constraints on operands are the same as those for
1822 the corresponding instruction (e.g. no bitwise operations on floating point
John Criswelle4c57cc2005-05-12 16:52:32 +0000[diff] [blame]1823 values are allowed).</dd>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1824</dl>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1825</div>
Chris Lattner9ee5d222004-03-08 16:49:10 +0000[diff] [blame]1826
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1827<!-- *********************************************************************** -->
Chris Lattnere87d6532006-01-25 23:47:57 +0000[diff] [blame]1828<div class="doc_section"> <a name="othervalues">Other Values</a> </div>
1829<!-- *********************************************************************** -->
1830
1831<!-- ======================================================================= -->
1832<div class="doc_subsection">
1833<a name="inlineasm">Inline Assembler Expressions</a>
1834</div>
1835
1836<div class="doc_text">
1837
1838<p>
1839LLVM supports inline assembler expressions (as opposed to <a href="#moduleasm">
1840Module-Level Inline Assembly</a>) through the use of a special value. This
1841value represents the inline assembler as a string (containing the instructions
1842to emit), a list of operand constraints (stored as a string), and a flag that
1843indicates whether or not the inline asm expression has side effects. An example
1844inline assembler expression is:
1845</p>
1846
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]1847<div class="doc_code">
Chris Lattnere87d6532006-01-25 23:47:57 +0000[diff] [blame]1848<pre>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]1849i32 (i32) asm "bswap $0", "=r,r"
Chris Lattnere87d6532006-01-25 23:47:57 +0000[diff] [blame]1850</pre>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]1851</div>
Chris Lattnere87d6532006-01-25 23:47:57 +0000[diff] [blame]1852
1853<p>
1854Inline assembler expressions may <b>only</b> be used as the callee operand of
1855a <a href="#i_call"><tt>call</tt> instruction</a>. Thus, typically we have:
1856</p>
1857
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]1858<div class="doc_code">
Chris Lattnere87d6532006-01-25 23:47:57 +0000[diff] [blame]1859<pre>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]1860%X = call i32 asm "<a href="#int_bswap">bswap</a> $0", "=r,r"(i32 %Y)
Chris Lattnere87d6532006-01-25 23:47:57 +0000[diff] [blame]1861</pre>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]1862</div>
Chris Lattnere87d6532006-01-25 23:47:57 +0000[diff] [blame]1863
1864<p>
1865Inline asms with side effects not visible in the constraint list must be marked
1866as having side effects. This is done through the use of the
1867'<tt>sideeffect</tt>' keyword, like so:
1868</p>
1869
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]1870<div class="doc_code">
Chris Lattnere87d6532006-01-25 23:47:57 +0000[diff] [blame]1871<pre>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]1872call void asm sideeffect "eieio", ""()
Chris Lattnere87d6532006-01-25 23:47:57 +0000[diff] [blame]1873</pre>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]1874</div>
Chris Lattnere87d6532006-01-25 23:47:57 +0000[diff] [blame]1875
1876<p>TODO: The format of the asm and constraints string still need to be
1877documented here. Constraints on what can be done (e.g. duplication, moving, etc
Chris Lattner4f993352008-10-04 18:36:02 +0000[diff] [blame]1878need to be documented). This is probably best done by reference to another
1879document that covers inline asm from a holistic perspective.
Chris Lattnere87d6532006-01-25 23:47:57 +0000[diff] [blame]1880</p>
1881
1882</div>
1883
1884<!-- *********************************************************************** -->
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1885<div class="doc_section"> <a name="instref">Instruction Reference</a> </div>
1886<!-- *********************************************************************** -->
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1887
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1888<div class="doc_text">
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1889
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1890<p>The LLVM instruction set consists of several different
1891classifications of instructions: <a href="#terminators">terminator
John Criswellc1f786c2005-05-13 22:25:59 +0000[diff] [blame]1892instructions</a>, <a href="#binaryops">binary instructions</a>,
1893<a href="#bitwiseops">bitwise binary instructions</a>, <a
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1894 href="#memoryops">memory instructions</a>, and <a href="#otherops">other
1895instructions</a>.</p>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1896
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1897</div>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1898
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1899<!-- ======================================================================= -->
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1900<div class="doc_subsection"> <a name="terminators">Terminator
1901Instructions</a> </div>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1902
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1903<div class="doc_text">
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1904
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1905<p>As mentioned <a href="#functionstructure">previously</a>, every
1906basic block in a program ends with a "Terminator" instruction, which
1907indicates which block should be executed after the current block is
1908finished. These terminator instructions typically yield a '<tt>void</tt>'
1909value: they produce control flow, not values (the one exception being
1910the '<a href="#i_invoke"><tt>invoke</tt></a>' instruction).</p>
John Criswell9e2485c2004-12-10 15:51:16 +0000[diff] [blame]1911<p>There are six different terminator instructions: the '<a
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1912 href="#i_ret"><tt>ret</tt></a>' instruction, the '<a href="#i_br"><tt>br</tt></a>'
1913instruction, the '<a href="#i_switch"><tt>switch</tt></a>' instruction,
Chris Lattner35eca582004-10-16 18:04:13 +0000[diff] [blame]1914the '<a href="#i_invoke"><tt>invoke</tt></a>' instruction, the '<a
1915 href="#i_unwind"><tt>unwind</tt></a>' instruction, and the '<a
1916 href="#i_unreachable"><tt>unreachable</tt></a>' instruction.</p>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1917
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1918</div>
Chris Lattnerc3f59762004-12-09 17:30:23 +0000[diff] [blame]1919
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1920<!-- _______________________________________________________________________ -->
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1921<div class="doc_subsubsection"> <a name="i_ret">'<tt>ret</tt>'
1922Instruction</a> </div>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1923<div class="doc_text">
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1924<h5>Syntax:</h5>
Dan Gohmanb1e6b962008-10-04 19:00:07 +0000[diff] [blame]1925<pre>
1926 ret &lt;type&gt; &lt;value&gt; <i>; Return a value from a non-void function</i>
Chris Lattner7faa8832002-04-14 06:13:44 +0000[diff] [blame]1927 ret void <i>; Return from void function</i>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1928</pre>
Chris Lattnerf4cde4e2008-04-23 04:59:35 +0000[diff] [blame]1929
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1930<h5>Overview:</h5>
Chris Lattnerf4cde4e2008-04-23 04:59:35 +0000[diff] [blame]1931
Dan Gohmanb1e6b962008-10-04 19:00:07 +0000[diff] [blame]1932<p>The '<tt>ret</tt>' instruction is used to return control flow (and
1933optionally a value) from a function back to the caller.</p>
John Criswell4457dc92004-04-09 16:48:45 +0000[diff] [blame]1934<p>There are two forms of the '<tt>ret</tt>' instruction: one that
Dan Gohmanb1e6b962008-10-04 19:00:07 +0000[diff] [blame]1935returns a value and then causes control flow, and one that just causes
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1936control flow to occur.</p>
Chris Lattnerf4cde4e2008-04-23 04:59:35 +0000[diff] [blame]1937
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1938<h5>Arguments:</h5>
Chris Lattnerf4cde4e2008-04-23 04:59:35 +0000[diff] [blame]1939
Dan Gohmanb1e6b962008-10-04 19:00:07 +0000[diff] [blame]1940<p>The '<tt>ret</tt>' instruction optionally accepts a single argument,
1941the return value. The type of the return value must be a
1942'<a href="#t_firstclass">first class</a>' type.</p>
1943
1944<p>A function is not <a href="#wellformed">well formed</a> if
1945it it has a non-void return type and contains a '<tt>ret</tt>'
1946instruction with no return value or a return value with a type that
1947does not match its type, or if it has a void return type and contains
1948a '<tt>ret</tt>' instruction with a return value.</p>
Chris Lattnerf4cde4e2008-04-23 04:59:35 +0000[diff] [blame]1949
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1950<h5>Semantics:</h5>
Chris Lattnerf4cde4e2008-04-23 04:59:35 +0000[diff] [blame]1951
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1952<p>When the '<tt>ret</tt>' instruction is executed, control flow
1953returns back to the calling function's context. If the caller is a "<a
John Criswellfa081872004-06-25 15:16:57 +0000[diff] [blame]1954 href="#i_call"><tt>call</tt></a>" instruction, execution continues at
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1955the instruction after the call. If the caller was an "<a
1956 href="#i_invoke"><tt>invoke</tt></a>" instruction, execution continues
John Criswelle4c57cc2005-05-12 16:52:32 +0000[diff] [blame]1957at the beginning of the "normal" destination block. If the instruction
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1958returns a value, that value shall set the call or invoke instruction's
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]1959return value.</p>
Chris Lattnerf4cde4e2008-04-23 04:59:35 +0000[diff] [blame]1960
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1961<h5>Example:</h5>
Chris Lattnerf4cde4e2008-04-23 04:59:35 +0000[diff] [blame]1962
1963<pre>
1964 ret i32 5 <i>; Return an integer value of 5</i>
Chris Lattner7faa8832002-04-14 06:13:44 +0000[diff] [blame]1965 ret void <i>; Return from a void function</i>
Dan Gohmanb1e6b962008-10-04 19:00:07 +0000[diff] [blame]1966 ret { i32, i8 } { i32 4, i8 2 } <i>; Return an aggregate of values 4 and 2</i>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1967</pre>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1968</div>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1969<!-- _______________________________________________________________________ -->
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1970<div class="doc_subsubsection"> <a name="i_br">'<tt>br</tt>' Instruction</a> </div>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1971<div class="doc_text">
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1972<h5>Syntax:</h5>
Reid Spencerc78f3372007-01-12 03:35:51 +0000[diff] [blame]1973<pre> br i1 &lt;cond&gt;, label &lt;iftrue&gt;, label &lt;iffalse&gt;<br> br label &lt;dest&gt; <i>; Unconditional branch</i>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1974</pre>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1975<h5>Overview:</h5>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1976<p>The '<tt>br</tt>' instruction is used to cause control flow to
1977transfer to a different basic block in the current function. There are
1978two forms of this instruction, corresponding to a conditional branch
1979and an unconditional branch.</p>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1980<h5>Arguments:</h5>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1981<p>The conditional branch form of the '<tt>br</tt>' instruction takes a
Reid Spencerc78f3372007-01-12 03:35:51 +0000[diff] [blame]1982single '<tt>i1</tt>' value and two '<tt>label</tt>' values. The
Reid Spencerde151942007-02-19 23:54:10 +0000[diff] [blame]1983unconditional form of the '<tt>br</tt>' instruction takes a single
1984'<tt>label</tt>' value as a target.</p>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1985<h5>Semantics:</h5>
Reid Spencerc78f3372007-01-12 03:35:51 +0000[diff] [blame]1986<p>Upon execution of a conditional '<tt>br</tt>' instruction, the '<tt>i1</tt>'
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]1987argument is evaluated. If the value is <tt>true</tt>, control flows
1988to the '<tt>iftrue</tt>' <tt>label</tt> argument. If "cond" is <tt>false</tt>,
1989control flows to the '<tt>iffalse</tt>' <tt>label</tt> argument.</p>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1990<h5>Example:</h5>
Reid Spencerc78f3372007-01-12 03:35:51 +0000[diff] [blame]1991<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 Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]1992 href="#i_ret">ret</a> i32 1<br>IfUnequal:<br> <a href="#i_ret">ret</a> i32 0<br></pre>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1993</div>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]1994<!-- _______________________________________________________________________ -->
Chris Lattnerc88c17b2004-02-24 04:54:45 +0000[diff] [blame]1995<div class="doc_subsubsection">
1996 <a name="i_switch">'<tt>switch</tt>' Instruction</a>
1997</div>
1998
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]1999<div class="doc_text">
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2000<h5>Syntax:</h5>
Chris Lattnerc88c17b2004-02-24 04:54:45 +0000[diff] [blame]2001
2002<pre>
2003 switch &lt;intty&gt; &lt;value&gt;, label &lt;defaultdest&gt; [ &lt;intty&gt; &lt;val&gt;, label &lt;dest&gt; ... ]
2004</pre>
2005
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2006<h5>Overview:</h5>
Chris Lattnerc88c17b2004-02-24 04:54:45 +0000[diff] [blame]2007
2008<p>The '<tt>switch</tt>' instruction is used to transfer control flow to one of
2009several different places. It is a generalization of the '<tt>br</tt>'
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2010instruction, allowing a branch to occur to one of many possible
2011destinations.</p>
Chris Lattnerc88c17b2004-02-24 04:54:45 +0000[diff] [blame]2012
2013
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2014<h5>Arguments:</h5>
Chris Lattnerc88c17b2004-02-24 04:54:45 +0000[diff] [blame]2015
2016<p>The '<tt>switch</tt>' instruction uses three parameters: an integer
2017comparison value '<tt>value</tt>', a default '<tt>label</tt>' destination, and
2018an array of pairs of comparison value constants and '<tt>label</tt>'s. The
2019table is not allowed to contain duplicate constant entries.</p>
2020
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2021<h5>Semantics:</h5>
Chris Lattnerc88c17b2004-02-24 04:54:45 +0000[diff] [blame]2022
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2023<p>The <tt>switch</tt> instruction specifies a table of values and
2024destinations. When the '<tt>switch</tt>' instruction is executed, this
John Criswell84114752004-06-25 16:05:06 +0000[diff] [blame]2025table is searched for the given value. If the value is found, control flow is
2026transfered to the corresponding destination; otherwise, control flow is
2027transfered to the default destination.</p>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2028
Chris Lattnerc88c17b2004-02-24 04:54:45 +0000[diff] [blame]2029<h5>Implementation:</h5>
2030
2031<p>Depending on properties of the target machine and the particular
2032<tt>switch</tt> instruction, this instruction may be code generated in different
John Criswell84114752004-06-25 16:05:06 +0000[diff] [blame]2033ways. For example, it could be generated as a series of chained conditional
2034branches or with a lookup table.</p>
Chris Lattnerc88c17b2004-02-24 04:54:45 +0000[diff] [blame]2035
2036<h5>Example:</h5>
2037
2038<pre>
2039 <i>; Emulate a conditional br instruction</i>
Reid Spencerc78f3372007-01-12 03:35:51 +0000[diff] [blame]2040 %Val = <a href="#i_zext">zext</a> i1 %value to i32
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]2041 switch i32 %Val, label %truedest [i32 0, label %falsedest ]
Chris Lattnerc88c17b2004-02-24 04:54:45 +0000[diff] [blame]2042
2043 <i>; Emulate an unconditional br instruction</i>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]2044 switch i32 0, label %dest [ ]
Chris Lattnerc88c17b2004-02-24 04:54:45 +0000[diff] [blame]2045
2046 <i>; Implement a jump table:</i>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]2047 switch i32 %val, label %otherwise [ i32 0, label %onzero
2048 i32 1, label %onone
2049 i32 2, label %ontwo ]
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2050</pre>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2051</div>
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]2052
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2053<!-- _______________________________________________________________________ -->
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]2054<div class="doc_subsubsection">
2055 <a name="i_invoke">'<tt>invoke</tt>' Instruction</a>
2056</div>
2057
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2058<div class="doc_text">
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]2059
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2060<h5>Syntax:</h5>
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]2061
2062<pre>
Devang Patel307e8ab2008-10-07 17:48:33 +0000[diff] [blame]2063 &lt;result&gt; = invoke [<a href="#callingconv">cconv</a>] [<a href="#paramattrs">ret attrs</a>] &lt;ptr to function ty&gt; &lt;function ptr val&gt;(&lt;function args&gt;) [<a href="#fnattrs">fn attrs</a>]
Chris Lattner76b8a332006-05-14 18:23:06 +0000[diff] [blame]2064 to label &lt;normal label&gt; unwind label &lt;exception label&gt;
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]2065</pre>
2066
Chris Lattner6536cfe2002-05-06 22:08:29 +0000[diff] [blame]2067<h5>Overview:</h5>
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]2068
2069<p>The '<tt>invoke</tt>' instruction causes control to transfer to a specified
2070function, with the possibility of control flow transfer to either the
John Criswelle4c57cc2005-05-12 16:52:32 +0000[diff] [blame]2071'<tt>normal</tt>' label or the
2072'<tt>exception</tt>' label. If the callee function returns with the
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]2073"<tt><a href="#i_ret">ret</a></tt>" instruction, control flow will return to the
2074"normal" label. If the callee (or any indirect callees) returns with the "<a
John Criswelle4c57cc2005-05-12 16:52:32 +0000[diff] [blame]2075href="#i_unwind"><tt>unwind</tt></a>" instruction, control is interrupted and
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]2076continued at the dynamically nearest "exception" label.</p>
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]2077
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2078<h5>Arguments:</h5>
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]2079
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2080<p>This instruction requires several arguments:</p>
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]2081
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2082<ol>
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]2083 <li>
Duncan Sands8036ca42007-03-30 12:22:09 +0000[diff] [blame]2084 The optional "cconv" marker indicates which <a href="#callingconv">calling
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]2085 convention</a> the call should use. If none is specified, the call defaults
2086 to using C calling conventions.
2087 </li>
Devang Patelf642f472008-10-06 18:50:38 +0000[diff] [blame]2088
2089 <li>The optional <a href="#paramattrs">Parameter Attributes</a> list for
2090 return values. Only '<tt>zeroext</tt>', '<tt>signext</tt>',
2091 and '<tt>inreg</tt>' attributes are valid here.</li>
2092
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]2093 <li>'<tt>ptr to function ty</tt>': shall be the signature of the pointer to
2094 function value being invoked. In most cases, this is a direct function
2095 invocation, but indirect <tt>invoke</tt>s are just as possible, branching off
2096 an arbitrary pointer to function value.
2097 </li>
2098
2099 <li>'<tt>function ptr val</tt>': An LLVM value containing a pointer to a
2100 function to be invoked. </li>
2101
2102 <li>'<tt>function args</tt>': argument list whose types match the function
2103 signature argument types. If the function signature indicates the function
2104 accepts a variable number of arguments, the extra arguments can be
2105 specified. </li>
2106
2107 <li>'<tt>normal label</tt>': the label reached when the called function
2108 executes a '<tt><a href="#i_ret">ret</a></tt>' instruction. </li>
2109
2110 <li>'<tt>exception label</tt>': the label reached when a callee returns with
2111 the <a href="#i_unwind"><tt>unwind</tt></a> instruction. </li>
2112
Devang Patel307e8ab2008-10-07 17:48:33 +0000[diff] [blame]2113 <li>The optional <a href="#fnattrs">function attributes</a> list. Only
Devang Patelf642f472008-10-06 18:50:38 +0000[diff] [blame]2114 '<tt>noreturn</tt>', '<tt>nounwind</tt>', '<tt>readonly</tt>' and
2115 '<tt>readnone</tt>' attributes are valid here.</li>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2116</ol>
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]2117
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2118<h5>Semantics:</h5>
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]2119
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2120<p>This instruction is designed to operate as a standard '<tt><a
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]2121href="#i_call">call</a></tt>' instruction in most regards. The primary
2122difference is that it establishes an association with a label, which is used by
2123the runtime library to unwind the stack.</p>
2124
2125<p>This instruction is used in languages with destructors to ensure that proper
2126cleanup is performed in the case of either a <tt>longjmp</tt> or a thrown
2127exception. Additionally, this is important for implementation of
2128'<tt>catch</tt>' clauses in high-level languages that support them.</p>
2129
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2130<h5>Example:</h5>
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]2131<pre>
Nick Lewyckyd703f652008-03-16 07:18:12 +0000[diff] [blame]2132 %retval = invoke i32 @Test(i32 15) to label %Continue
Jeff Cohen6f1cc772007-04-22 01:17:39 +0000[diff] [blame]2133 unwind label %TestCleanup <i>; {i32}:retval set</i>
Nick Lewyckyd703f652008-03-16 07:18:12 +0000[diff] [blame]2134 %retval = invoke <a href="#callingconv">coldcc</a> i32 %Testfnptr(i32 15) to label %Continue
Jeff Cohen6f1cc772007-04-22 01:17:39 +0000[diff] [blame]2135 unwind label %TestCleanup <i>; {i32}:retval set</i>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2136</pre>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2137</div>
Chris Lattner35eca582004-10-16 18:04:13 +0000[diff] [blame]2138
2139
Chris Lattner27f71f22003-09-03 00:41:47 +0000[diff] [blame]2140<!-- _______________________________________________________________________ -->
Chris Lattner35eca582004-10-16 18:04:13 +0000[diff] [blame]2141
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2142<div class="doc_subsubsection"> <a name="i_unwind">'<tt>unwind</tt>'
2143Instruction</a> </div>
Chris Lattner35eca582004-10-16 18:04:13 +0000[diff] [blame]2144
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2145<div class="doc_text">
Chris Lattner35eca582004-10-16 18:04:13 +0000[diff] [blame]2146
Chris Lattner27f71f22003-09-03 00:41:47 +0000[diff] [blame]2147<h5>Syntax:</h5>
Chris Lattner35eca582004-10-16 18:04:13 +0000[diff] [blame]2148<pre>
2149 unwind
2150</pre>
2151
Chris Lattner27f71f22003-09-03 00:41:47 +0000[diff] [blame]2152<h5>Overview:</h5>
Chris Lattner35eca582004-10-16 18:04:13 +0000[diff] [blame]2153
2154<p>The '<tt>unwind</tt>' instruction unwinds the stack, continuing control flow
2155at the first callee in the dynamic call stack which used an <a
2156href="#i_invoke"><tt>invoke</tt></a> instruction to perform the call. This is
2157primarily used to implement exception handling.</p>
2158
Chris Lattner27f71f22003-09-03 00:41:47 +0000[diff] [blame]2159<h5>Semantics:</h5>
Chris Lattner35eca582004-10-16 18:04:13 +0000[diff] [blame]2160
Chris Lattner72ed2002008-04-19 21:01:16 +0000[diff] [blame]2161<p>The '<tt>unwind</tt>' instruction causes execution of the current function to
Chris Lattner35eca582004-10-16 18:04:13 +0000[diff] [blame]2162immediately halt. The dynamic call stack is then searched for the first <a
2163href="#i_invoke"><tt>invoke</tt></a> instruction on the call stack. Once found,
2164execution continues at the "exceptional" destination block specified by the
2165<tt>invoke</tt> instruction. If there is no <tt>invoke</tt> instruction in the
2166dynamic call chain, undefined behavior results.</p>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2167</div>
Chris Lattner35eca582004-10-16 18:04:13 +0000[diff] [blame]2168
2169<!-- _______________________________________________________________________ -->
2170
2171<div class="doc_subsubsection"> <a name="i_unreachable">'<tt>unreachable</tt>'
2172Instruction</a> </div>
2173
2174<div class="doc_text">
2175
2176<h5>Syntax:</h5>
2177<pre>
2178 unreachable
2179</pre>
2180
2181<h5>Overview:</h5>
2182
2183<p>The '<tt>unreachable</tt>' instruction has no defined semantics. This
2184instruction is used to inform the optimizer that a particular portion of the
2185code is not reachable. This can be used to indicate that the code after a
2186no-return function cannot be reached, and other facts.</p>
2187
2188<h5>Semantics:</h5>
2189
2190<p>The '<tt>unreachable</tt>' instruction has no defined semantics.</p>
2191</div>
2192
2193
2194
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2195<!-- ======================================================================= -->
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2196<div class="doc_subsection"> <a name="binaryops">Binary Operations</a> </div>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2197<div class="doc_text">
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2198<p>Binary operators are used to do most of the computation in a
Chris Lattner5a158142008-04-01 18:47:32 +0000[diff] [blame]2199program. They require two operands of the same type, execute an operation on them, and
John Criswell9e2485c2004-12-10 15:51:16 +0000[diff] [blame]2200produce a single value. The operands might represent
Reid Spencer485bad12007-02-15 03:07:05 +0000[diff] [blame]2201multiple data, as is the case with the <a href="#t_vector">vector</a> data type.
Chris Lattner5a158142008-04-01 18:47:32 +0000[diff] [blame]2202The result value has the same type as its operands.</p>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2203<p>There are several different binary operators:</p>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2204</div>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2205<!-- _______________________________________________________________________ -->
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2206<div class="doc_subsubsection">
2207 <a name="i_add">'<tt>add</tt>' Instruction</a>
2208</div>
2209
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2210<div class="doc_text">
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2211
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2212<h5>Syntax:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2213
2214<pre>
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2215 &lt;result&gt; = add &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2216</pre>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2217
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2218<h5>Overview:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2219
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2220<p>The '<tt>add</tt>' instruction returns the sum of its two operands.</p>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2221
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2222<h5>Arguments:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2223
2224<p>The two arguments to the '<tt>add</tt>' instruction must be <a
2225 href="#t_integer">integer</a>, <a href="#t_floating">floating point</a>, or
2226 <a href="#t_vector">vector</a> values. Both arguments must have identical
2227 types.</p>
2228
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2229<h5>Semantics:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2230
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2231<p>The value produced is the integer or floating point sum of the two
2232operands.</p>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2233
Chris Lattner5ec89832008-01-28 00:36:27 +0000[diff] [blame]2234<p>If an integer sum has unsigned overflow, the result returned is the
2235mathematical result modulo 2<sup>n</sup>, where n is the bit width of
2236the result.</p>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2237
Chris Lattner5ec89832008-01-28 00:36:27 +0000[diff] [blame]2238<p>Because LLVM integers use a two's complement representation, this
2239instruction is appropriate for both signed and unsigned integers.</p>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2240
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2241<h5>Example:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2242
2243<pre>
2244 &lt;result&gt; = add i32 4, %var <i>; yields {i32}:result = 4 + %var</i>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2245</pre>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2246</div>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2247<!-- _______________________________________________________________________ -->
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2248<div class="doc_subsubsection">
2249 <a name="i_sub">'<tt>sub</tt>' Instruction</a>
2250</div>
2251
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2252<div class="doc_text">
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2253
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2254<h5>Syntax:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2255
2256<pre>
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2257 &lt;result&gt; = sub &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2258</pre>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2259
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2260<h5>Overview:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2261
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2262<p>The '<tt>sub</tt>' instruction returns the difference of its two
2263operands.</p>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2264
2265<p>Note that the '<tt>sub</tt>' instruction is used to represent the
2266'<tt>neg</tt>' instruction present in most other intermediate
2267representations.</p>
2268
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2269<h5>Arguments:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2270
2271<p>The two arguments to the '<tt>sub</tt>' instruction must be <a
2272 href="#t_integer">integer</a>, <a href="#t_floating">floating point</a>,
2273 or <a href="#t_vector">vector</a> values. Both arguments must have identical
2274 types.</p>
2275
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2276<h5>Semantics:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2277
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2278<p>The value produced is the integer or floating point difference of
2279the two operands.</p>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2280
Chris Lattner5ec89832008-01-28 00:36:27 +0000[diff] [blame]2281<p>If an integer difference has unsigned overflow, the result returned is the
2282mathematical result modulo 2<sup>n</sup>, where n is the bit width of
2283the result.</p>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2284
Chris Lattner5ec89832008-01-28 00:36:27 +0000[diff] [blame]2285<p>Because LLVM integers use a two's complement representation, this
2286instruction is appropriate for both signed and unsigned integers.</p>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2287
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2288<h5>Example:</h5>
Bill Wendlingaac388b2007-05-29 09:42:13 +0000[diff] [blame]2289<pre>
2290 &lt;result&gt; = sub i32 4, %var <i>; yields {i32}:result = 4 - %var</i>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]2291 &lt;result&gt; = sub i32 0, %val <i>; yields {i32}:result = -%var</i>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2292</pre>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2293</div>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2294
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2295<!-- _______________________________________________________________________ -->
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2296<div class="doc_subsubsection">
2297 <a name="i_mul">'<tt>mul</tt>' Instruction</a>
2298</div>
2299
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2300<div class="doc_text">
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2301
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2302<h5>Syntax:</h5>
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2303<pre> &lt;result&gt; = mul &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2304</pre>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2305<h5>Overview:</h5>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2306<p>The '<tt>mul</tt>' instruction returns the product of its two
2307operands.</p>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2308
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2309<h5>Arguments:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2310
2311<p>The two arguments to the '<tt>mul</tt>' instruction must be <a
2312href="#t_integer">integer</a>, <a href="#t_floating">floating point</a>,
2313or <a href="#t_vector">vector</a> values. Both arguments must have identical
2314types.</p>
2315
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2316<h5>Semantics:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2317
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2318<p>The value produced is the integer or floating point product of the
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2319two operands.</p>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2320
Chris Lattner5ec89832008-01-28 00:36:27 +0000[diff] [blame]2321<p>If the result of an integer multiplication has unsigned overflow,
2322the result returned is the mathematical result modulo
23232<sup>n</sup>, where n is the bit width of the result.</p>
2324<p>Because LLVM integers use a two's complement representation, and the
2325result is the same width as the operands, this instruction returns the
2326correct result for both signed and unsigned integers. If a full product
2327(e.g. <tt>i32</tt>x<tt>i32</tt>-><tt>i64</tt>) is needed, the operands
2328should be sign-extended or zero-extended as appropriate to the
2329width of the full product.</p>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2330<h5>Example:</h5>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]2331<pre> &lt;result&gt; = mul i32 4, %var <i>; yields {i32}:result = 4 * %var</i>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2332</pre>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2333</div>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2334
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2335<!-- _______________________________________________________________________ -->
Reid Spencer1628cec2006-10-26 06:15:43 +0000[diff] [blame]2336<div class="doc_subsubsection"> <a name="i_udiv">'<tt>udiv</tt>' Instruction
2337</a></div>
2338<div class="doc_text">
2339<h5>Syntax:</h5>
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2340<pre> &lt;result&gt; = udiv &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
Reid Spencer1628cec2006-10-26 06:15:43 +0000[diff] [blame]2341</pre>
2342<h5>Overview:</h5>
2343<p>The '<tt>udiv</tt>' instruction returns the quotient of its two
2344operands.</p>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2345
Reid Spencer1628cec2006-10-26 06:15:43 +0000[diff] [blame]2346<h5>Arguments:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2347
Reid Spencer1628cec2006-10-26 06:15:43 +0000[diff] [blame]2348<p>The two arguments to the '<tt>udiv</tt>' instruction must be
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2349<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
2350values. Both arguments must have identical types.</p>
2351
Reid Spencer1628cec2006-10-26 06:15:43 +0000[diff] [blame]2352<h5>Semantics:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2353
Chris Lattner5ec89832008-01-28 00:36:27 +0000[diff] [blame]2354<p>The value produced is the unsigned integer quotient of the two operands.</p>
2355<p>Note that unsigned integer division and signed integer division are distinct
2356operations; for signed integer division, use '<tt>sdiv</tt>'.</p>
2357<p>Division by zero leads to undefined behavior.</p>
Reid Spencer1628cec2006-10-26 06:15:43 +0000[diff] [blame]2358<h5>Example:</h5>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]2359<pre> &lt;result&gt; = udiv i32 4, %var <i>; yields {i32}:result = 4 / %var</i>
Reid Spencer1628cec2006-10-26 06:15:43 +0000[diff] [blame]2360</pre>
2361</div>
2362<!-- _______________________________________________________________________ -->
2363<div class="doc_subsubsection"> <a name="i_sdiv">'<tt>sdiv</tt>' Instruction
2364</a> </div>
2365<div class="doc_text">
2366<h5>Syntax:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2367<pre>
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2368 &lt;result&gt; = sdiv &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
Reid Spencer1628cec2006-10-26 06:15:43 +0000[diff] [blame]2369</pre>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2370
Reid Spencer1628cec2006-10-26 06:15:43 +0000[diff] [blame]2371<h5>Overview:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2372
Reid Spencer1628cec2006-10-26 06:15:43 +0000[diff] [blame]2373<p>The '<tt>sdiv</tt>' instruction returns the quotient of its two
2374operands.</p>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2375
Reid Spencer1628cec2006-10-26 06:15:43 +0000[diff] [blame]2376<h5>Arguments:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2377
2378<p>The two arguments to the '<tt>sdiv</tt>' instruction must be
2379<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
2380values. Both arguments must have identical types.</p>
2381
Reid Spencer1628cec2006-10-26 06:15:43 +0000[diff] [blame]2382<h5>Semantics:</h5>
Chris Lattnera73afe02008-04-01 18:45:27 +0000[diff] [blame]2383<p>The value produced is the signed integer quotient of the two operands rounded towards zero.</p>
Chris Lattner5ec89832008-01-28 00:36:27 +0000[diff] [blame]2384<p>Note that signed integer division and unsigned integer division are distinct
2385operations; for unsigned integer division, use '<tt>udiv</tt>'.</p>
2386<p>Division by zero leads to undefined behavior. Overflow also leads to
2387undefined behavior; this is a rare case, but can occur, for example,
2388by doing a 32-bit division of -2147483648 by -1.</p>
Reid Spencer1628cec2006-10-26 06:15:43 +0000[diff] [blame]2389<h5>Example:</h5>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]2390<pre> &lt;result&gt; = sdiv i32 4, %var <i>; yields {i32}:result = 4 / %var</i>
Reid Spencer1628cec2006-10-26 06:15:43 +0000[diff] [blame]2391</pre>
2392</div>
2393<!-- _______________________________________________________________________ -->
2394<div class="doc_subsubsection"> <a name="i_fdiv">'<tt>fdiv</tt>'
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2395Instruction</a> </div>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2396<div class="doc_text">
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2397<h5>Syntax:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2398<pre>
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2399 &lt;result&gt; = fdiv &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2400</pre>
2401<h5>Overview:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2402
Reid Spencer1628cec2006-10-26 06:15:43 +0000[diff] [blame]2403<p>The '<tt>fdiv</tt>' instruction returns the quotient of its two
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2404operands.</p>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2405
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2406<h5>Arguments:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2407
Jeff Cohen6f1cc772007-04-22 01:17:39 +0000[diff] [blame]2408<p>The two arguments to the '<tt>fdiv</tt>' instruction must be
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2409<a href="#t_floating">floating point</a> or <a href="#t_vector">vector</a>
2410of floating point values. Both arguments must have identical types.</p>
2411
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2412<h5>Semantics:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2413
Reid Spencer1628cec2006-10-26 06:15:43 +0000[diff] [blame]2414<p>The value produced is the floating point quotient of the two operands.</p>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2415
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2416<h5>Example:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2417
2418<pre>
2419 &lt;result&gt; = fdiv float 4.0, %var <i>; yields {float}:result = 4.0 / %var</i>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2420</pre>
2421</div>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2422
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2423<!-- _______________________________________________________________________ -->
Reid Spencer0a783f72006-11-02 01:53:59 +0000[diff] [blame]2424<div class="doc_subsubsection"> <a name="i_urem">'<tt>urem</tt>' Instruction</a>
2425</div>
2426<div class="doc_text">
2427<h5>Syntax:</h5>
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2428<pre> &lt;result&gt; = urem &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
Reid Spencer0a783f72006-11-02 01:53:59 +0000[diff] [blame]2429</pre>
2430<h5>Overview:</h5>
2431<p>The '<tt>urem</tt>' instruction returns the remainder from the
2432unsigned division of its two arguments.</p>
2433<h5>Arguments:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2434<p>The two arguments to the '<tt>urem</tt>' instruction must be
2435<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
2436values. Both arguments must have identical types.</p>
Reid Spencer0a783f72006-11-02 01:53:59 +0000[diff] [blame]2437<h5>Semantics:</h5>
2438<p>This instruction returns the unsigned integer <i>remainder</i> of a division.
Chris Lattnera73afe02008-04-01 18:45:27 +0000[diff] [blame]2439This instruction always performs an unsigned division to get the remainder.</p>
Chris Lattner5ec89832008-01-28 00:36:27 +0000[diff] [blame]2440<p>Note that unsigned integer remainder and signed integer remainder are
2441distinct operations; for signed integer remainder, use '<tt>srem</tt>'.</p>
2442<p>Taking the remainder of a division by zero leads to undefined behavior.</p>
Reid Spencer0a783f72006-11-02 01:53:59 +0000[diff] [blame]2443<h5>Example:</h5>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]2444<pre> &lt;result&gt; = urem i32 4, %var <i>; yields {i32}:result = 4 % %var</i>
Reid Spencer0a783f72006-11-02 01:53:59 +0000[diff] [blame]2445</pre>
2446
2447</div>
2448<!-- _______________________________________________________________________ -->
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2449<div class="doc_subsubsection">
2450 <a name="i_srem">'<tt>srem</tt>' Instruction</a>
2451</div>
2452
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2453<div class="doc_text">
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2454
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2455<h5>Syntax:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2456
2457<pre>
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2458 &lt;result&gt; = srem &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2459</pre>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2460
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2461<h5>Overview:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2462
Reid Spencer0a783f72006-11-02 01:53:59 +0000[diff] [blame]2463<p>The '<tt>srem</tt>' instruction returns the remainder from the
Dan Gohman80176312007-11-05 23:35:22 +0000[diff] [blame]2464signed division of its two operands. This instruction can also take
2465<a href="#t_vector">vector</a> versions of the values in which case
2466the elements must be integers.</p>
Chris Lattnerc7d3ab32008-01-04 04:33:49 +0000[diff] [blame]2467
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2468<h5>Arguments:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2469
Reid Spencer0a783f72006-11-02 01:53:59 +0000[diff] [blame]2470<p>The two arguments to the '<tt>srem</tt>' instruction must be
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2471<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
2472values. Both arguments must have identical types.</p>
2473
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2474<h5>Semantics:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2475
Reid Spencer0a783f72006-11-02 01:53:59 +0000[diff] [blame]2476<p>This instruction returns the <i>remainder</i> of a division (where the result
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2477has the same sign as the dividend, <tt>op1</tt>), not the <i>modulo</i>
2478operator (where the result has the same sign as the divisor, <tt>op2</tt>) of
Reid Spencerc9fdfc82007-03-24 22:23:39 +0000[diff] [blame]2479a value. For more information about the difference, see <a
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2480 href="http://mathforum.org/dr.math/problems/anne.4.28.99.html">The
Reid Spencerc9fdfc82007-03-24 22:23:39 +0000[diff] [blame]2481Math Forum</a>. For a table of how this is implemented in various languages,
Reid Spencer64f5c6c2007-03-24 22:40:44 +0000[diff] [blame]2482please see <a href="http://en.wikipedia.org/wiki/Modulo_operation">
Reid Spencerc9fdfc82007-03-24 22:23:39 +0000[diff] [blame]2483Wikipedia: modulo operation</a>.</p>
Chris Lattner5ec89832008-01-28 00:36:27 +0000[diff] [blame]2484<p>Note that signed integer remainder and unsigned integer remainder are
2485distinct operations; for unsigned integer remainder, use '<tt>urem</tt>'.</p>
2486<p>Taking the remainder of a division by zero leads to undefined behavior.
2487Overflow also leads to undefined behavior; this is a rare case, but can occur,
2488for example, by taking the remainder of a 32-bit division of -2147483648 by -1.
2489(The remainder doesn't actually overflow, but this rule lets srem be
2490implemented using instructions that return both the result of the division
2491and the remainder.)</p>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2492<h5>Example:</h5>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]2493<pre> &lt;result&gt; = srem i32 4, %var <i>; yields {i32}:result = 4 % %var</i>
Reid Spencer0a783f72006-11-02 01:53:59 +0000[diff] [blame]2494</pre>
2495
2496</div>
2497<!-- _______________________________________________________________________ -->
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2498<div class="doc_subsubsection">
2499 <a name="i_frem">'<tt>frem</tt>' Instruction</a> </div>
2500
Reid Spencer0a783f72006-11-02 01:53:59 +0000[diff] [blame]2501<div class="doc_text">
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2502
Reid Spencer0a783f72006-11-02 01:53:59 +0000[diff] [blame]2503<h5>Syntax:</h5>
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2504<pre> &lt;result&gt; = frem &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
Reid Spencer0a783f72006-11-02 01:53:59 +0000[diff] [blame]2505</pre>
2506<h5>Overview:</h5>
2507<p>The '<tt>frem</tt>' instruction returns the remainder from the
2508division of its two operands.</p>
2509<h5>Arguments:</h5>
2510<p>The two arguments to the '<tt>frem</tt>' instruction must be
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2511<a href="#t_floating">floating point</a> or <a href="#t_vector">vector</a>
2512of floating point values. Both arguments must have identical types.</p>
2513
Reid Spencer0a783f72006-11-02 01:53:59 +0000[diff] [blame]2514<h5>Semantics:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2515
Chris Lattnera73afe02008-04-01 18:45:27 +0000[diff] [blame]2516<p>This instruction returns the <i>remainder</i> of a division.
2517The remainder has the same sign as the dividend.</p>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2518
Reid Spencer0a783f72006-11-02 01:53:59 +0000[diff] [blame]2519<h5>Example:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2520
2521<pre>
2522 &lt;result&gt; = frem float 4.0, %var <i>; yields {float}:result = 4.0 % %var</i>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2523</pre>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2524</div>
Robert Bocchino7b81c752006-02-17 21:18:08 +0000[diff] [blame]2525
Reid Spencer8e11bf82007-02-02 13:57:07 +0000[diff] [blame]2526<!-- ======================================================================= -->
2527<div class="doc_subsection"> <a name="bitwiseops">Bitwise Binary
2528Operations</a> </div>
2529<div class="doc_text">
2530<p>Bitwise binary operators are used to do various forms of
2531bit-twiddling in a program. They are generally very efficient
2532instructions and can commonly be strength reduced from other
Chris Lattnera73afe02008-04-01 18:45:27 +0000[diff] [blame]2533instructions. They require two operands of the same type, execute an operation on them,
2534and produce a single value. The resulting value is the same type as its operands.</p>
Reid Spencer8e11bf82007-02-02 13:57:07 +0000[diff] [blame]2535</div>
2536
Reid Spencer569f2fa2007-01-31 21:39:12 +0000[diff] [blame]2537<!-- _______________________________________________________________________ -->
2538<div class="doc_subsubsection"> <a name="i_shl">'<tt>shl</tt>'
2539Instruction</a> </div>
2540<div class="doc_text">
2541<h5>Syntax:</h5>
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2542<pre> &lt;result&gt; = shl &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
Reid Spencer569f2fa2007-01-31 21:39:12 +0000[diff] [blame]2543</pre>
Chris Lattner6ccc2d52007-10-03 21:01:14 +0000[diff] [blame]2544
Reid Spencer569f2fa2007-01-31 21:39:12 +0000[diff] [blame]2545<h5>Overview:</h5>
Chris Lattner6ccc2d52007-10-03 21:01:14 +0000[diff] [blame]2546
Reid Spencer569f2fa2007-01-31 21:39:12 +0000[diff] [blame]2547<p>The '<tt>shl</tt>' instruction returns the first operand shifted to
2548the left a specified number of bits.</p>
Chris Lattner6ccc2d52007-10-03 21:01:14 +0000[diff] [blame]2549
Reid Spencer569f2fa2007-01-31 21:39:12 +0000[diff] [blame]2550<h5>Arguments:</h5>
Chris Lattner6ccc2d52007-10-03 21:01:14 +0000[diff] [blame]2551
Reid Spencer569f2fa2007-01-31 21:39:12 +0000[diff] [blame]2552<p>Both arguments to the '<tt>shl</tt>' instruction must be the same <a
Nate Begeman5bc1ea02008-07-29 15:49:41 +0000[diff] [blame]2553 href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2554type. '<tt>op2</tt>' is treated as an unsigned value.</p>
Chris Lattner6ccc2d52007-10-03 21:01:14 +0000[diff] [blame]2555
Reid Spencer569f2fa2007-01-31 21:39:12 +0000[diff] [blame]2556<h5>Semantics:</h5>
Chris Lattner6ccc2d52007-10-03 21:01:14 +0000[diff] [blame]2557
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2558<p>The value produced is <tt>op1</tt> * 2<sup><tt>op2</tt></sup> mod 2<sup>n</sup>,
2559where n is the width of the result. If <tt>op2</tt> is (statically or dynamically) negative or
2560equal to or larger than the number of bits in <tt>op1</tt>, the result is undefined.</p>
Chris Lattner6ccc2d52007-10-03 21:01:14 +0000[diff] [blame]2561
Reid Spencer569f2fa2007-01-31 21:39:12 +0000[diff] [blame]2562<h5>Example:</h5><pre>
2563 &lt;result&gt; = shl i32 4, %var <i>; yields {i32}: 4 &lt;&lt; %var</i>
2564 &lt;result&gt; = shl i32 4, 2 <i>; yields {i32}: 16</i>
2565 &lt;result&gt; = shl i32 1, 10 <i>; yields {i32}: 1024</i>
Chris Lattner6ccc2d52007-10-03 21:01:14 +0000[diff] [blame]2566 &lt;result&gt; = shl i32 1, 32 <i>; undefined</i>
Reid Spencer569f2fa2007-01-31 21:39:12 +0000[diff] [blame]2567</pre>
2568</div>
2569<!-- _______________________________________________________________________ -->
2570<div class="doc_subsubsection"> <a name="i_lshr">'<tt>lshr</tt>'
2571Instruction</a> </div>
2572<div class="doc_text">
2573<h5>Syntax:</h5>
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2574<pre> &lt;result&gt; = lshr &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
Reid Spencer569f2fa2007-01-31 21:39:12 +0000[diff] [blame]2575</pre>
2576
2577<h5>Overview:</h5>
2578<p>The '<tt>lshr</tt>' instruction (logical shift right) returns the first
Jeff Cohen6f1cc772007-04-22 01:17:39 +0000[diff] [blame]2579operand shifted to the right a specified number of bits with zero fill.</p>
Reid Spencer569f2fa2007-01-31 21:39:12 +0000[diff] [blame]2580
2581<h5>Arguments:</h5>
2582<p>Both arguments to the '<tt>lshr</tt>' instruction must be the same
Nate Begeman5bc1ea02008-07-29 15:49:41 +0000[diff] [blame]2583<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2584type. '<tt>op2</tt>' is treated as an unsigned value.</p>
Reid Spencer569f2fa2007-01-31 21:39:12 +0000[diff] [blame]2585
2586<h5>Semantics:</h5>
Chris Lattner6ccc2d52007-10-03 21:01:14 +0000[diff] [blame]2587
Reid Spencer569f2fa2007-01-31 21:39:12 +0000[diff] [blame]2588<p>This instruction always performs a logical shift right operation. The most
2589significant bits of the result will be filled with zero bits after the
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2590shift. If <tt>op2</tt> is (statically or dynamically) equal to or larger than
2591the number of bits in <tt>op1</tt>, the result is undefined.</p>
Reid Spencer569f2fa2007-01-31 21:39:12 +0000[diff] [blame]2592
2593<h5>Example:</h5>
2594<pre>
2595 &lt;result&gt; = lshr i32 4, 1 <i>; yields {i32}:result = 2</i>
2596 &lt;result&gt; = lshr i32 4, 2 <i>; yields {i32}:result = 1</i>
2597 &lt;result&gt; = lshr i8 4, 3 <i>; yields {i8}:result = 0</i>
2598 &lt;result&gt; = lshr i8 -2, 1 <i>; yields {i8}:result = 0x7FFFFFFF </i>
Chris Lattner6ccc2d52007-10-03 21:01:14 +0000[diff] [blame]2599 &lt;result&gt; = lshr i32 1, 32 <i>; undefined</i>
Reid Spencer569f2fa2007-01-31 21:39:12 +0000[diff] [blame]2600</pre>
2601</div>
2602
Reid Spencer8e11bf82007-02-02 13:57:07 +0000[diff] [blame]2603<!-- _______________________________________________________________________ -->
Reid Spencer569f2fa2007-01-31 21:39:12 +0000[diff] [blame]2604<div class="doc_subsubsection"> <a name="i_ashr">'<tt>ashr</tt>'
2605Instruction</a> </div>
2606<div class="doc_text">
2607
2608<h5>Syntax:</h5>
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2609<pre> &lt;result&gt; = ashr &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
Reid Spencer569f2fa2007-01-31 21:39:12 +0000[diff] [blame]2610</pre>
2611
2612<h5>Overview:</h5>
2613<p>The '<tt>ashr</tt>' instruction (arithmetic shift right) returns the first
Jeff Cohen6f1cc772007-04-22 01:17:39 +0000[diff] [blame]2614operand shifted to the right a specified number of bits with sign extension.</p>
Reid Spencer569f2fa2007-01-31 21:39:12 +0000[diff] [blame]2615
2616<h5>Arguments:</h5>
2617<p>Both arguments to the '<tt>ashr</tt>' instruction must be the same
Nate Begeman5bc1ea02008-07-29 15:49:41 +0000[diff] [blame]2618<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2619type. '<tt>op2</tt>' is treated as an unsigned value.</p>
Reid Spencer569f2fa2007-01-31 21:39:12 +0000[diff] [blame]2620
2621<h5>Semantics:</h5>
2622<p>This instruction always performs an arithmetic shift right operation,
2623The most significant bits of the result will be filled with the sign bit
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2624of <tt>op1</tt>. If <tt>op2</tt> is (statically or dynamically) equal to or
2625larger than the number of bits in <tt>op1</tt>, the result is undefined.
Chris Lattner6ccc2d52007-10-03 21:01:14 +0000[diff] [blame]2626</p>
Reid Spencer569f2fa2007-01-31 21:39:12 +0000[diff] [blame]2627
2628<h5>Example:</h5>
2629<pre>
2630 &lt;result&gt; = ashr i32 4, 1 <i>; yields {i32}:result = 2</i>
2631 &lt;result&gt; = ashr i32 4, 2 <i>; yields {i32}:result = 1</i>
2632 &lt;result&gt; = ashr i8 4, 3 <i>; yields {i8}:result = 0</i>
2633 &lt;result&gt; = ashr i8 -2, 1 <i>; yields {i8}:result = -1</i>
Chris Lattner6ccc2d52007-10-03 21:01:14 +0000[diff] [blame]2634 &lt;result&gt; = ashr i32 1, 32 <i>; undefined</i>
Reid Spencer569f2fa2007-01-31 21:39:12 +0000[diff] [blame]2635</pre>
2636</div>
2637
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2638<!-- _______________________________________________________________________ -->
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2639<div class="doc_subsubsection"> <a name="i_and">'<tt>and</tt>'
2640Instruction</a> </div>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2641
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2642<div class="doc_text">
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2643
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2644<h5>Syntax:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2645
2646<pre>
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2647 &lt;result&gt; = and &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2648</pre>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2649
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2650<h5>Overview:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2651
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2652<p>The '<tt>and</tt>' instruction returns the bitwise logical and of
2653its two operands.</p>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2654
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2655<h5>Arguments:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2656
2657<p>The two arguments to the '<tt>and</tt>' instruction must be
2658<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
2659values. Both arguments must have identical types.</p>
2660
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2661<h5>Semantics:</h5>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2662<p>The truth table used for the '<tt>and</tt>' instruction is:</p>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2663<p> </p>
Bill Wendlingc7e4c4d2008-09-07 10:29:20 +0000[diff] [blame]2664<div>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2665<table border="1" cellspacing="0" cellpadding="4">
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2666 <tbody>
2667 <tr>
2668 <td>In0</td>
2669 <td>In1</td>
2670 <td>Out</td>
2671 </tr>
2672 <tr>
2673 <td>0</td>
2674 <td>0</td>
2675 <td>0</td>
2676 </tr>
2677 <tr>
2678 <td>0</td>
2679 <td>1</td>
2680 <td>0</td>
2681 </tr>
2682 <tr>
2683 <td>1</td>
2684 <td>0</td>
2685 <td>0</td>
2686 </tr>
2687 <tr>
2688 <td>1</td>
2689 <td>1</td>
2690 <td>1</td>
2691 </tr>
2692 </tbody>
2693</table>
Misha Brukmandaa4cb02004-03-01 17:47:27 +0000[diff] [blame]2694</div>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2695<h5>Example:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2696<pre>
2697 &lt;result&gt; = and i32 4, %var <i>; yields {i32}:result = 4 &amp; %var</i>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]2698 &lt;result&gt; = and i32 15, 40 <i>; yields {i32}:result = 8</i>
2699 &lt;result&gt; = and i32 4, 8 <i>; yields {i32}:result = 0</i>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2700</pre>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2701</div>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2702<!-- _______________________________________________________________________ -->
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2703<div class="doc_subsubsection"> <a name="i_or">'<tt>or</tt>' Instruction</a> </div>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2704<div class="doc_text">
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2705<h5>Syntax:</h5>
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2706<pre> &lt;result&gt; = or &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2707</pre>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2708<h5>Overview:</h5>
2709<p>The '<tt>or</tt>' instruction returns the bitwise logical inclusive
2710or of its two operands.</p>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2711<h5>Arguments:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2712
2713<p>The two arguments to the '<tt>or</tt>' instruction must be
2714<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
2715values. Both arguments must have identical types.</p>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2716<h5>Semantics:</h5>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2717<p>The truth table used for the '<tt>or</tt>' instruction is:</p>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2718<p> </p>
Bill Wendlingc7e4c4d2008-09-07 10:29:20 +0000[diff] [blame]2719<div>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2720<table border="1" cellspacing="0" cellpadding="4">
2721 <tbody>
2722 <tr>
2723 <td>In0</td>
2724 <td>In1</td>
2725 <td>Out</td>
2726 </tr>
2727 <tr>
2728 <td>0</td>
2729 <td>0</td>
2730 <td>0</td>
2731 </tr>
2732 <tr>
2733 <td>0</td>
2734 <td>1</td>
2735 <td>1</td>
2736 </tr>
2737 <tr>
2738 <td>1</td>
2739 <td>0</td>
2740 <td>1</td>
2741 </tr>
2742 <tr>
2743 <td>1</td>
2744 <td>1</td>
2745 <td>1</td>
2746 </tr>
2747 </tbody>
2748</table>
Misha Brukmandaa4cb02004-03-01 17:47:27 +0000[diff] [blame]2749</div>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2750<h5>Example:</h5>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]2751<pre> &lt;result&gt; = or i32 4, %var <i>; yields {i32}:result = 4 | %var</i>
2752 &lt;result&gt; = or i32 15, 40 <i>; yields {i32}:result = 47</i>
2753 &lt;result&gt; = or i32 4, 8 <i>; yields {i32}:result = 12</i>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2754</pre>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2755</div>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2756<!-- _______________________________________________________________________ -->
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2757<div class="doc_subsubsection"> <a name="i_xor">'<tt>xor</tt>'
2758Instruction</a> </div>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2759<div class="doc_text">
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2760<h5>Syntax:</h5>
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]2761<pre> &lt;result&gt; = xor &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2762</pre>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2763<h5>Overview:</h5>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2764<p>The '<tt>xor</tt>' instruction returns the bitwise logical exclusive
2765or of its two operands. The <tt>xor</tt> is used to implement the
2766"one's complement" operation, which is the "~" operator in C.</p>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2767<h5>Arguments:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2768<p>The two arguments to the '<tt>xor</tt>' instruction must be
2769<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
2770values. Both arguments must have identical types.</p>
2771
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2772<h5>Semantics:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]2773
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2774<p>The truth table used for the '<tt>xor</tt>' instruction is:</p>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2775<p> </p>
Bill Wendlingc7e4c4d2008-09-07 10:29:20 +0000[diff] [blame]2776<div>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2777<table border="1" cellspacing="0" cellpadding="4">
2778 <tbody>
2779 <tr>
2780 <td>In0</td>
2781 <td>In1</td>
2782 <td>Out</td>
2783 </tr>
2784 <tr>
2785 <td>0</td>
2786 <td>0</td>
2787 <td>0</td>
2788 </tr>
2789 <tr>
2790 <td>0</td>
2791 <td>1</td>
2792 <td>1</td>
2793 </tr>
2794 <tr>
2795 <td>1</td>
2796 <td>0</td>
2797 <td>1</td>
2798 </tr>
2799 <tr>
2800 <td>1</td>
2801 <td>1</td>
2802 <td>0</td>
2803 </tr>
2804 </tbody>
2805</table>
Misha Brukmandaa4cb02004-03-01 17:47:27 +0000[diff] [blame]2806</div>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]2807<p> </p>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2808<h5>Example:</h5>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]2809<pre> &lt;result&gt; = xor i32 4, %var <i>; yields {i32}:result = 4 ^ %var</i>
2810 &lt;result&gt; = xor i32 15, 40 <i>; yields {i32}:result = 39</i>
2811 &lt;result&gt; = xor i32 4, 8 <i>; yields {i32}:result = 12</i>
2812 &lt;result&gt; = xor i32 %V, -1 <i>; yields {i32}:result = ~%V</i>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2813</pre>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]2814</div>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]2815
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]2816<!-- ======================================================================= -->
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]2817<div class="doc_subsection">
Chris Lattner3df241e2006-04-08 23:07:04 +0000[diff] [blame]2818 <a name="vectorops">Vector Operations</a>
2819</div>
2820
2821<div class="doc_text">
2822
2823<p>LLVM supports several instructions to represent vector operations in a
Jeff Cohen6f1cc772007-04-22 01:17:39 +0000[diff] [blame]2824target-independent manner. These instructions cover the element-access and
Chris Lattner3df241e2006-04-08 23:07:04 +0000[diff] [blame]2825vector-specific operations needed to process vectors effectively. While LLVM
2826does directly support these vector operations, many sophisticated algorithms
2827will want to use target-specific intrinsics to take full advantage of a specific
2828target.</p>
2829
2830</div>
2831
2832<!-- _______________________________________________________________________ -->
2833<div class="doc_subsubsection">
2834 <a name="i_extractelement">'<tt>extractelement</tt>' Instruction</a>
2835</div>
2836
2837<div class="doc_text">
2838
2839<h5>Syntax:</h5>
2840
2841<pre>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]2842 &lt;result&gt; = extractelement &lt;n x &lt;ty&gt;&gt; &lt;val&gt;, i32 &lt;idx&gt; <i>; yields &lt;ty&gt;</i>
Chris Lattner3df241e2006-04-08 23:07:04 +0000[diff] [blame]2843</pre>
2844
2845<h5>Overview:</h5>
2846
2847<p>
2848The '<tt>extractelement</tt>' instruction extracts a single scalar
Reid Spencer485bad12007-02-15 03:07:05 +0000[diff] [blame]2849element from a vector at a specified index.
Chris Lattner3df241e2006-04-08 23:07:04 +0000[diff] [blame]2850</p>
2851
2852
2853<h5>Arguments:</h5>
2854
2855<p>
2856The first operand of an '<tt>extractelement</tt>' instruction is a
Reid Spencer485bad12007-02-15 03:07:05 +0000[diff] [blame]2857value of <a href="#t_vector">vector</a> type. The second operand is
Chris Lattner3df241e2006-04-08 23:07:04 +0000[diff] [blame]2858an index indicating the position from which to extract the element.
2859The index may be a variable.</p>
2860
2861<h5>Semantics:</h5>
2862
2863<p>
2864The result is a scalar of the same type as the element type of
2865<tt>val</tt>. Its value is the value at position <tt>idx</tt> of
2866<tt>val</tt>. If <tt>idx</tt> exceeds the length of <tt>val</tt>, the
2867results are undefined.
2868</p>
2869
2870<h5>Example:</h5>
2871
2872<pre>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]2873 %result = extractelement &lt;4 x i32&gt; %vec, i32 0 <i>; yields i32</i>
Chris Lattner3df241e2006-04-08 23:07:04 +0000[diff] [blame]2874</pre>
2875</div>
2876
2877
2878<!-- _______________________________________________________________________ -->
2879<div class="doc_subsubsection">
2880 <a name="i_insertelement">'<tt>insertelement</tt>' Instruction</a>
2881</div>
2882
2883<div class="doc_text">
2884
2885<h5>Syntax:</h5>
2886
2887<pre>
Dan Gohmanf3480b92008-05-12 23:38:42 +0000[diff] [blame]2888 &lt;result&gt; = insertelement &lt;n x &lt;ty&gt;&gt; &lt;val&gt;, &lt;ty&gt; &lt;elt&gt;, i32 &lt;idx&gt; <i>; yields &lt;n x &lt;ty&gt;&gt;</i>
Chris Lattner3df241e2006-04-08 23:07:04 +0000[diff] [blame]2889</pre>
2890
2891<h5>Overview:</h5>
2892
2893<p>
2894The '<tt>insertelement</tt>' instruction inserts a scalar
Reid Spencer485bad12007-02-15 03:07:05 +0000[diff] [blame]2895element into a vector at a specified index.
Chris Lattner3df241e2006-04-08 23:07:04 +0000[diff] [blame]2896</p>
2897
2898
2899<h5>Arguments:</h5>
2900
2901<p>
2902The first operand of an '<tt>insertelement</tt>' instruction is a
Reid Spencer485bad12007-02-15 03:07:05 +0000[diff] [blame]2903value of <a href="#t_vector">vector</a> type. The second operand is a
Chris Lattner3df241e2006-04-08 23:07:04 +0000[diff] [blame]2904scalar value whose type must equal the element type of the first
2905operand. The third operand is an index indicating the position at
2906which to insert the value. The index may be a variable.</p>
2907
2908<h5>Semantics:</h5>
2909
2910<p>
Reid Spencer485bad12007-02-15 03:07:05 +0000[diff] [blame]2911The result is a vector of the same type as <tt>val</tt>. Its
Chris Lattner3df241e2006-04-08 23:07:04 +0000[diff] [blame]2912element values are those of <tt>val</tt> except at position
2913<tt>idx</tt>, where it gets the value <tt>elt</tt>. If <tt>idx</tt>
2914exceeds the length of <tt>val</tt>, the results are undefined.
2915</p>
2916
2917<h5>Example:</h5>
2918
2919<pre>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]2920 %result = insertelement &lt;4 x i32&gt; %vec, i32 1, i32 0 <i>; yields &lt;4 x i32&gt;</i>
Chris Lattner3df241e2006-04-08 23:07:04 +0000[diff] [blame]2921</pre>
2922</div>
2923
2924<!-- _______________________________________________________________________ -->
2925<div class="doc_subsubsection">
2926 <a name="i_shufflevector">'<tt>shufflevector</tt>' Instruction</a>
2927</div>
2928
2929<div class="doc_text">
2930
2931<h5>Syntax:</h5>
2932
2933<pre>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]2934 &lt;result&gt; = shufflevector &lt;n x &lt;ty&gt;&gt; &lt;v1&gt;, &lt;n x &lt;ty&gt;&gt; &lt;v2&gt;, &lt;n x i32&gt; &lt;mask&gt; <i>; yields &lt;n x &lt;ty&gt;&gt;</i>
Chris Lattner3df241e2006-04-08 23:07:04 +0000[diff] [blame]2935</pre>
2936
2937<h5>Overview:</h5>
2938
2939<p>
2940The '<tt>shufflevector</tt>' instruction constructs a permutation of elements
2941from two input vectors, returning a vector of the same type.
2942</p>
2943
2944<h5>Arguments:</h5>
2945
2946<p>
2947The first two operands of a '<tt>shufflevector</tt>' instruction are vectors
2948with types that match each other and types that match the result of the
2949instruction. The third argument is a shuffle mask, which has the same number
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]2950of elements as the other vector type, but whose element type is always 'i32'.
Chris Lattner3df241e2006-04-08 23:07:04 +0000[diff] [blame]2951</p>
2952
2953<p>
2954The shuffle mask operand is required to be a constant vector with either
2955constant integer or undef values.
2956</p>
2957
2958<h5>Semantics:</h5>
2959
2960<p>
2961The elements of the two input vectors are numbered from left to right across
2962both of the vectors. The shuffle mask operand specifies, for each element of
2963the result vector, which element of the two input registers the result element
2964gets. The element selector may be undef (meaning "don't care") and the second
2965operand may be undef if performing a shuffle from only one vector.
2966</p>
2967
2968<h5>Example:</h5>
2969
2970<pre>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]2971 %result = shufflevector &lt;4 x i32&gt; %v1, &lt;4 x i32&gt; %v2,
Jeff Cohen6f1cc772007-04-22 01:17:39 +0000[diff] [blame]2972 &lt;4 x i32&gt; &lt;i32 0, i32 4, i32 1, i32 5&gt; <i>; yields &lt;4 x i32&gt;</i>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]2973 %result = shufflevector &lt;4 x i32&gt; %v1, &lt;4 x i32&gt; undef,
2974 &lt;4 x i32&gt; &lt;i32 0, i32 1, i32 2, i32 3&gt; <i>; yields &lt;4 x i32&gt;</i> - Identity shuffle.
Chris Lattner3df241e2006-04-08 23:07:04 +0000[diff] [blame]2975</pre>
2976</div>
2977
Tanya Lattner09474292006-04-14 19:24:33 +0000[diff] [blame]2978
Chris Lattner3df241e2006-04-08 23:07:04 +0000[diff] [blame]2979<!-- ======================================================================= -->
2980<div class="doc_subsection">
Dan Gohmana334d5f2008-05-12 23:51:09 +0000[diff] [blame]2981 <a name="aggregateops">Aggregate Operations</a>
2982</div>
2983
2984<div class="doc_text">
2985
2986<p>LLVM supports several instructions for working with aggregate values.
2987</p>
2988
2989</div>
2990
2991<!-- _______________________________________________________________________ -->
2992<div class="doc_subsubsection">
2993 <a name="i_extractvalue">'<tt>extractvalue</tt>' Instruction</a>
2994</div>
2995
2996<div class="doc_text">
2997
2998<h5>Syntax:</h5>
2999
3000<pre>
3001 &lt;result&gt; = extractvalue &lt;aggregate type&gt; &lt;val&gt;, &lt;idx&gt;{, &lt;idx&gt;}*
3002</pre>
3003
3004<h5>Overview:</h5>
3005
3006<p>
Dan Gohmanc3dac5c2008-05-13 18:16:06 +0000[diff] [blame]3007The '<tt>extractvalue</tt>' instruction extracts the value of a struct field
3008or array element from an aggregate value.
Dan Gohmana334d5f2008-05-12 23:51:09 +0000[diff] [blame]3009</p>
3010
3011
3012<h5>Arguments:</h5>
3013
3014<p>
3015The first operand of an '<tt>extractvalue</tt>' instruction is a
3016value of <a href="#t_struct">struct</a> or <a href="#t_array">array</a>
Dan Gohmanc3dac5c2008-05-13 18:16:06 +0000[diff] [blame]3017type. The operands are constant indices to specify which value to extract
Dan Gohman81a0c0b2008-05-31 00:58:22 +0000[diff] [blame]3018in a similar manner as indices in a
Dan Gohmana334d5f2008-05-12 23:51:09 +0000[diff] [blame]3019'<tt><a href="#i_getelementptr">getelementptr</a></tt>' instruction.
3020</p>
3021
3022<h5>Semantics:</h5>
3023
3024<p>
3025The result is the value at the position in the aggregate specified by
3026the index operands.
3027</p>
3028
3029<h5>Example:</h5>
3030
3031<pre>
Dan Gohman81a0c0b2008-05-31 00:58:22 +0000[diff] [blame]3032 %result = extractvalue {i32, float} %agg, 0 <i>; yields i32</i>
Dan Gohmana334d5f2008-05-12 23:51:09 +0000[diff] [blame]3033</pre>
3034</div>
3035
3036
3037<!-- _______________________________________________________________________ -->
3038<div class="doc_subsubsection">
3039 <a name="i_insertvalue">'<tt>insertvalue</tt>' Instruction</a>
3040</div>
3041
3042<div class="doc_text">
3043
3044<h5>Syntax:</h5>
3045
3046<pre>
Dan Gohman81a0c0b2008-05-31 00:58:22 +0000[diff] [blame]3047 &lt;result&gt; = insertvalue &lt;aggregate type&gt; &lt;val&gt;, &lt;ty&gt; &lt;val&gt;, &lt;idx&gt; <i>; yields &lt;n x &lt;ty&gt;&gt;</i>
Dan Gohmana334d5f2008-05-12 23:51:09 +0000[diff] [blame]3048</pre>
3049
3050<h5>Overview:</h5>
3051
3052<p>
3053The '<tt>insertvalue</tt>' instruction inserts a value
Dan Gohmanc3dac5c2008-05-13 18:16:06 +0000[diff] [blame]3054into a struct field or array element in an aggregate.
Dan Gohmana334d5f2008-05-12 23:51:09 +0000[diff] [blame]3055</p>
3056
3057
3058<h5>Arguments:</h5>
3059
3060<p>
3061The first operand of an '<tt>insertvalue</tt>' instruction is a
3062value of <a href="#t_struct">struct</a> or <a href="#t_array">array</a> type.
3063The second operand is a first-class value to insert.
Dan Gohmanc4b49eb2008-05-23 21:53:15 +0000[diff] [blame]3064The following operands are constant indices
Dan Gohman81a0c0b2008-05-31 00:58:22 +0000[diff] [blame]3065indicating the position at which to insert the value in a similar manner as
Dan Gohmanc3dac5c2008-05-13 18:16:06 +0000[diff] [blame]3066indices in a
Dan Gohmana334d5f2008-05-12 23:51:09 +0000[diff] [blame]3067'<tt><a href="#i_getelementptr">getelementptr</a></tt>' instruction.
3068The value to insert must have the same type as the value identified
Dan Gohmanc3dac5c2008-05-13 18:16:06 +0000[diff] [blame]3069by the indices.
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]3070</p>
Dan Gohmana334d5f2008-05-12 23:51:09 +0000[diff] [blame]3071
3072<h5>Semantics:</h5>
3073
3074<p>
3075The result is an aggregate of the same type as <tt>val</tt>. Its
3076value is that of <tt>val</tt> except that the value at the position
Dan Gohmanc3dac5c2008-05-13 18:16:06 +0000[diff] [blame]3077specified by the indices is that of <tt>elt</tt>.
Dan Gohmana334d5f2008-05-12 23:51:09 +0000[diff] [blame]3078</p>
3079
3080<h5>Example:</h5>
3081
3082<pre>
Dan Gohman52bb2db2008-06-23 15:26:37 +0000[diff] [blame]3083 %result = insertvalue {i32, float} %agg, i32 1, 0 <i>; yields {i32, float}</i>
Dan Gohmana334d5f2008-05-12 23:51:09 +0000[diff] [blame]3084</pre>
3085</div>
3086
3087
3088<!-- ======================================================================= -->
3089<div class="doc_subsection">
Chris Lattner884a9702006-08-15 00:45:58 +0000[diff] [blame]3090 <a name="memoryops">Memory Access and Addressing Operations</a>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3091</div>
3092
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3093<div class="doc_text">
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3094
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]3095<p>A key design point of an SSA-based representation is how it
3096represents memory. In LLVM, no memory locations are in SSA form, which
3097makes things very simple. This section describes how to read, write,
John Criswell9e2485c2004-12-10 15:51:16 +0000[diff] [blame]3098allocate, and free memory in LLVM.</p>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3099
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3100</div>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3101
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3102<!-- _______________________________________________________________________ -->
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3103<div class="doc_subsubsection">
3104 <a name="i_malloc">'<tt>malloc</tt>' Instruction</a>
3105</div>
3106
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3107<div class="doc_text">
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3108
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3109<h5>Syntax:</h5>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3110
3111<pre>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3112 &lt;result&gt; = malloc &lt;type&gt;[, i32 &lt;NumElements&gt;][, align &lt;alignment&gt;] <i>; yields {type*}:result</i>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3113</pre>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3114
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3115<h5>Overview:</h5>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3116
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]3117<p>The '<tt>malloc</tt>' instruction allocates memory from the system
Christopher Lamb303dae92007-12-17 01:00:21 +0000[diff] [blame]3118heap and returns a pointer to it. The object is always allocated in the generic
3119address space (address space zero).</p>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3120
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3121<h5>Arguments:</h5>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3122
3123<p>The '<tt>malloc</tt>' instruction allocates
3124<tt>sizeof(&lt;type&gt;)*NumElements</tt>
John Criswell6e4ca612004-02-24 16:13:56 +0000[diff] [blame]3125bytes of memory from the operating system and returns a pointer of the
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3126appropriate type to the program. If "NumElements" is specified, it is the
Gabor Greif1acd2ee2008-02-09 22:24:34 +0000[diff] [blame]3127number of elements allocated, otherwise "NumElements" is defaulted to be one.
Chris Lattner4316dec2008-04-02 00:38:26 +0000[diff] [blame]3128If a constant alignment is specified, the value result of the allocation is guaranteed to
Gabor Greif1acd2ee2008-02-09 22:24:34 +0000[diff] [blame]3129be aligned to at least that boundary. If not specified, or if zero, the target can
3130choose to align the allocation on any convenient boundary.</p>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3131
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3132<p>'<tt>type</tt>' must be a sized type.</p>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3133
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3134<h5>Semantics:</h5>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3135
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]3136<p>Memory is allocated using the system "<tt>malloc</tt>" function, and
Chris Lattner72ed2002008-04-19 21:01:16 +0000[diff] [blame]3137a pointer is returned. The result of a zero byte allocattion is undefined. The
3138result is null if there is insufficient memory available.</p>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3139
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3140<h5>Example:</h5>
3141
3142<pre>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3143 %array = malloc [4 x i8 ] <i>; yields {[%4 x i8]*}:array</i>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3144
Bill Wendlingaac388b2007-05-29 09:42:13 +0000[diff] [blame]3145 %size = <a href="#i_add">add</a> i32 2, 2 <i>; yields {i32}:size = i32 4</i>
3146 %array1 = malloc i8, i32 4 <i>; yields {i8*}:array1</i>
3147 %array2 = malloc [12 x i8], i32 %size <i>; yields {[12 x i8]*}:array2</i>
3148 %array3 = malloc i32, i32 4, align 1024 <i>; yields {i32*}:array3</i>
3149 %array4 = malloc i32, align 1024 <i>; yields {i32*}:array4</i>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3150</pre>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3151</div>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3152
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3153<!-- _______________________________________________________________________ -->
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3154<div class="doc_subsubsection">
3155 <a name="i_free">'<tt>free</tt>' Instruction</a>
3156</div>
3157
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3158<div class="doc_text">
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3159
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3160<h5>Syntax:</h5>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3161
3162<pre>
3163 free &lt;type&gt; &lt;value&gt; <i>; yields {void}</i>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3164</pre>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3165
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3166<h5>Overview:</h5>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3167
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]3168<p>The '<tt>free</tt>' instruction returns memory back to the unused
John Criswellc1f786c2005-05-13 22:25:59 +0000[diff] [blame]3169memory heap to be reallocated in the future.</p>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3170
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3171<h5>Arguments:</h5>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3172
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]3173<p>'<tt>value</tt>' shall be a pointer value that points to a value
3174that was allocated with the '<tt><a href="#i_malloc">malloc</a></tt>'
3175instruction.</p>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3176
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3177<h5>Semantics:</h5>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3178
John Criswell9e2485c2004-12-10 15:51:16 +0000[diff] [blame]3179<p>Access to the memory pointed to by the pointer is no longer defined
Chris Lattnere0db56d2008-04-19 22:41:32 +0000[diff] [blame]3180after this instruction executes. If the pointer is null, the operation
3181is a noop.</p>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3182
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3183<h5>Example:</h5>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3184
3185<pre>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3186 %array = <a href="#i_malloc">malloc</a> [4 x i8] <i>; yields {[4 x i8]*}:array</i>
3187 free [4 x i8]* %array
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3188</pre>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3189</div>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3190
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3191<!-- _______________________________________________________________________ -->
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3192<div class="doc_subsubsection">
3193 <a name="i_alloca">'<tt>alloca</tt>' Instruction</a>
3194</div>
3195
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3196<div class="doc_text">
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3197
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3198<h5>Syntax:</h5>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3199
3200<pre>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3201 &lt;result&gt; = alloca &lt;type&gt;[, i32 &lt;NumElements&gt;][, align &lt;alignment&gt;] <i>; yields {type*}:result</i>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3202</pre>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3203
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3204<h5>Overview:</h5>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3205
Jeff Cohen6f1cc772007-04-22 01:17:39 +0000[diff] [blame]3206<p>The '<tt>alloca</tt>' instruction allocates memory on the stack frame of the
3207currently executing function, to be automatically released when this function
Christopher Lamb303dae92007-12-17 01:00:21 +0000[diff] [blame]3208returns to its caller. The object is always allocated in the generic address
3209space (address space zero).</p>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3210
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3211<h5>Arguments:</h5>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3212
John Criswell9e2485c2004-12-10 15:51:16 +0000[diff] [blame]3213<p>The '<tt>alloca</tt>' instruction allocates <tt>sizeof(&lt;type&gt;)*NumElements</tt>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]3214bytes of memory on the runtime stack, returning a pointer of the
Gabor Greif1acd2ee2008-02-09 22:24:34 +0000[diff] [blame]3215appropriate type to the program. If "NumElements" is specified, it is the
3216number of elements allocated, otherwise "NumElements" is defaulted to be one.
Chris Lattner4316dec2008-04-02 00:38:26 +0000[diff] [blame]3217If a constant alignment is specified, the value result of the allocation is guaranteed
Gabor Greif1acd2ee2008-02-09 22:24:34 +0000[diff] [blame]3218to be aligned to at least that boundary. If not specified, or if zero, the target
3219can choose to align the allocation on any convenient boundary.</p>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3220
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3221<p>'<tt>type</tt>' may be any sized type.</p>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3222
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3223<h5>Semantics:</h5>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3224
Chris Lattner72ed2002008-04-19 21:01:16 +0000[diff] [blame]3225<p>Memory is allocated; a pointer is returned. The operation is undefiend if
3226there is insufficient stack space for the allocation. '<tt>alloca</tt>'d
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]3227memory is automatically released when the function returns. The '<tt>alloca</tt>'
3228instruction is commonly used to represent automatic variables that must
3229have an address available. When the function returns (either with the <tt><a
John Criswelldae2e932005-05-12 16:55:34 +0000[diff] [blame]3230 href="#i_ret">ret</a></tt> or <tt><a href="#i_unwind">unwind</a></tt>
Chris Lattner4316dec2008-04-02 00:38:26 +0000[diff] [blame]3231instructions), the memory is reclaimed. Allocating zero bytes
3232is legal, but the result is undefined.</p>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3233
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3234<h5>Example:</h5>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3235
3236<pre>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3237 %ptr = alloca i32 <i>; yields {i32*}:ptr</i>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]3238 %ptr = alloca i32, i32 4 <i>; yields {i32*}:ptr</i>
3239 %ptr = alloca i32, i32 4, align 1024 <i>; yields {i32*}:ptr</i>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3240 %ptr = alloca i32, align 1024 <i>; yields {i32*}:ptr</i>
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3241</pre>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3242</div>
Chris Lattner2cbdc452005-11-06 08:02:57 +0000[diff] [blame]3243
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3244<!-- _______________________________________________________________________ -->
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]3245<div class="doc_subsubsection"> <a name="i_load">'<tt>load</tt>'
3246Instruction</a> </div>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3247<div class="doc_text">
Chris Lattner2b7d3202002-05-06 03:03:22 +0000[diff] [blame]3248<h5>Syntax:</h5>
Christopher Lamb2330e4d2007-04-21 08:16:25 +0000[diff] [blame]3249<pre> &lt;result&gt; = load &lt;ty&gt;* &lt;pointer&gt;[, align &lt;alignment&gt;]<br> &lt;result&gt; = volatile load &lt;ty&gt;* &lt;pointer&gt;[, align &lt;alignment&gt;]<br></pre>
Chris Lattner2b7d3202002-05-06 03:03:22 +0000[diff] [blame]3250<h5>Overview:</h5>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3251<p>The '<tt>load</tt>' instruction is used to read from memory.</p>
Chris Lattner2b7d3202002-05-06 03:03:22 +0000[diff] [blame]3252<h5>Arguments:</h5>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]3253<p>The argument to the '<tt>load</tt>' instruction specifies the memory
John Criswell0ec250c2005-10-24 16:17:18 +0000[diff] [blame]3254address from which to load. The pointer must point to a <a
Chris Lattnere53e5082004-06-03 22:57:15 +0000[diff] [blame]3255 href="#t_firstclass">first class</a> type. If the <tt>load</tt> is
John Criswell0ec250c2005-10-24 16:17:18 +0000[diff] [blame]3256marked as <tt>volatile</tt>, then the optimizer is not allowed to modify
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]3257the number or order of execution of this <tt>load</tt> with other
3258volatile <tt>load</tt> and <tt><a href="#i_store">store</a></tt>
3259instructions. </p>
Chris Lattnera31d1d72008-01-06 21:04:43 +0000[diff] [blame]3260<p>
Chris Lattner4316dec2008-04-02 00:38:26 +0000[diff] [blame]3261The optional constant "align" argument specifies the alignment of the operation
Chris Lattnera31d1d72008-01-06 21:04:43 +0000[diff] [blame]3262(that is, the alignment of the memory address). A value of 0 or an
3263omitted "align" argument means that the operation has the preferential
3264alignment for the target. It is the responsibility of the code emitter
3265to ensure that the alignment information is correct. Overestimating
3266the alignment results in an undefined behavior. Underestimating the
3267alignment may produce less efficient code. An alignment of 1 is always
3268safe.
3269</p>
Chris Lattner2b7d3202002-05-06 03:03:22 +0000[diff] [blame]3270<h5>Semantics:</h5>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3271<p>The location of memory pointed to is loaded.</p>
Chris Lattner2b7d3202002-05-06 03:03:22 +0000[diff] [blame]3272<h5>Examples:</h5>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3273<pre> %ptr = <a href="#i_alloca">alloca</a> i32 <i>; yields {i32*}:ptr</i>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]3274 <a
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3275 href="#i_store">store</a> i32 3, i32* %ptr <i>; yields {void}</i>
3276 %val = load i32* %ptr <i>; yields {i32}:val = i32 3</i>
Chris Lattner2b7d3202002-05-06 03:03:22 +0000[diff] [blame]3277</pre>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3278</div>
Chris Lattner2b7d3202002-05-06 03:03:22 +0000[diff] [blame]3279<!-- _______________________________________________________________________ -->
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]3280<div class="doc_subsubsection"> <a name="i_store">'<tt>store</tt>'
3281Instruction</a> </div>
Reid Spencer035ab572006-11-09 21:18:01 +0000[diff] [blame]3282<div class="doc_text">
Chris Lattner2b7d3202002-05-06 03:03:22 +0000[diff] [blame]3283<h5>Syntax:</h5>
Christopher Lamb2330e4d2007-04-21 08:16:25 +0000[diff] [blame]3284<pre> store &lt;ty&gt; &lt;value&gt;, &lt;ty&gt;* &lt;pointer&gt;[, align &lt;alignment&gt;] <i>; yields {void}</i>
3285 volatile store &lt;ty&gt; &lt;value&gt;, &lt;ty&gt;* &lt;pointer&gt;[, align &lt;alignment&gt;] <i>; yields {void}</i>
Chris Lattner2b7d3202002-05-06 03:03:22 +0000[diff] [blame]3286</pre>
Chris Lattner2b7d3202002-05-06 03:03:22 +0000[diff] [blame]3287<h5>Overview:</h5>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3288<p>The '<tt>store</tt>' instruction is used to write to memory.</p>
Chris Lattner2b7d3202002-05-06 03:03:22 +0000[diff] [blame]3289<h5>Arguments:</h5>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]3290<p>There are two arguments to the '<tt>store</tt>' instruction: a value
Jeff Cohen6f1cc772007-04-22 01:17:39 +0000[diff] [blame]3291to store and an address at which to store it. The type of the '<tt>&lt;pointer&gt;</tt>'
Chris Lattner4316dec2008-04-02 00:38:26 +0000[diff] [blame]3292operand must be a pointer to the <a href="#t_firstclass">first class</a> type
3293of the '<tt>&lt;value&gt;</tt>'
John Criswellc1f786c2005-05-13 22:25:59 +0000[diff] [blame]3294operand. If the <tt>store</tt> is marked as <tt>volatile</tt>, then the
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]3295optimizer is not allowed to modify the number or order of execution of
3296this <tt>store</tt> with other volatile <tt>load</tt> and <tt><a
3297 href="#i_store">store</a></tt> instructions.</p>
Chris Lattnera31d1d72008-01-06 21:04:43 +0000[diff] [blame]3298<p>
Chris Lattner4316dec2008-04-02 00:38:26 +0000[diff] [blame]3299The optional constant "align" argument specifies the alignment of the operation
Chris Lattnera31d1d72008-01-06 21:04:43 +0000[diff] [blame]3300(that is, the alignment of the memory address). A value of 0 or an
3301omitted "align" argument means that the operation has the preferential
3302alignment for the target. It is the responsibility of the code emitter
3303to ensure that the alignment information is correct. Overestimating
3304the alignment results in an undefined behavior. Underestimating the
3305alignment may produce less efficient code. An alignment of 1 is always
3306safe.
3307</p>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]3308<h5>Semantics:</h5>
3309<p>The contents of memory are updated to contain '<tt>&lt;value&gt;</tt>'
3310at the location specified by the '<tt>&lt;pointer&gt;</tt>' operand.</p>
Chris Lattner2b7d3202002-05-06 03:03:22 +0000[diff] [blame]3311<h5>Example:</h5>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3312<pre> %ptr = <a href="#i_alloca">alloca</a> i32 <i>; yields {i32*}:ptr</i>
Bill Wendling8c6c72d2007-10-22 05:10:05 +0000[diff] [blame]3313 store i32 3, i32* %ptr <i>; yields {void}</i>
3314 %val = <a href="#i_load">load</a> i32* %ptr <i>; yields {i32}:val = i32 3</i>
Chris Lattner2b7d3202002-05-06 03:03:22 +0000[diff] [blame]3315</pre>
Reid Spencer47ce1792006-11-09 21:15:49 +0000[diff] [blame]3316</div>
3317
Chris Lattner2b7d3202002-05-06 03:03:22 +0000[diff] [blame]3318<!-- _______________________________________________________________________ -->
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3319<div class="doc_subsubsection">
3320 <a name="i_getelementptr">'<tt>getelementptr</tt>' Instruction</a>
3321</div>
3322
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3323<div class="doc_text">
Chris Lattner7faa8832002-04-14 06:13:44 +0000[diff] [blame]3324<h5>Syntax:</h5>
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3325<pre>
Matthijs Kooijmane49d0bc2008-10-13 13:44:15 +0000[diff] [blame]3326 &lt;result&gt; = getelementptr &lt;pty&gt;* &lt;ptrval&gt;{, &lt;ty&gt; &lt;idx&gt;}*
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3327</pre>
3328
Chris Lattner7faa8832002-04-14 06:13:44 +0000[diff] [blame]3329<h5>Overview:</h5>
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3330
3331<p>
3332The '<tt>getelementptr</tt>' instruction is used to get the address of a
Matthijs Kooijmane49d0bc2008-10-13 13:44:15 +0000[diff] [blame]3333subelement of an aggregate data structure. It performs address calculation only
3334and does not access memory.</p>
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3335
Chris Lattner7faa8832002-04-14 06:13:44 +0000[diff] [blame]3336<h5>Arguments:</h5>
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3337
Matthijs Kooijmane49d0bc2008-10-13 13:44:15 +0000[diff] [blame]3338<p>The first argument is always a pointer, and forms the basis of the
3339calculation. The remaining arguments are indices, that indicate which of the
3340elements of the aggregate object are indexed. The interpretation of each index
3341is dependent on the type being indexed into. The first index always indexes the
3342pointer value given as the first argument, the second index indexes a value of
3343the type pointed to (not necessarily the value directly pointed to, since the
3344first index can be non-zero), etc. The first type indexed into must be a pointer
3345value, subsequent types can be arrays, vectors and structs. Note that subsequent
3346types being indexed into can never be pointers, since that would require loading
3347the pointer before continuing calculation.</p>
3348
3349<p>The type of each index argument depends on the type it is indexing into.
3350When indexing into a (packed) structure, only <tt>i32</tt> integer
3351<b>constants</b> are allowed. When indexing into an array, pointer or vector,
3352only integers of 32 or 64 bits are allowed (also non-constants). 32-bit values
3353will be sign extended to 64-bits if required.</p>
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3354
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]3355<p>For example, let's consider a C code fragment and how it gets
3356compiled to LLVM:</p>
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3357
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]3358<div class="doc_code">
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3359<pre>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]3360struct RT {
3361 char A;
Chris Lattnercabc8462007-05-29 15:43:56 +0000[diff] [blame]3362 int B[10][20];
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]3363 char C;
3364};
3365struct ST {
Chris Lattnercabc8462007-05-29 15:43:56 +0000[diff] [blame]3366 int X;
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]3367 double Y;
3368 struct RT Z;
3369};
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3370
Chris Lattnercabc8462007-05-29 15:43:56 +0000[diff] [blame]3371int *foo(struct ST *s) {
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]3372 return &amp;s[1].Z.B[5][13];
3373}
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3374</pre>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]3375</div>
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3376
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3377<p>The LLVM code generated by the GCC frontend is:</p>
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3378
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]3379<div class="doc_code">
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3380<pre>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]3381%RT = type { i8 , [10 x [20 x i32]], i8 }
3382%ST = type { i32, double, %RT }
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3383
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]3384define i32* %foo(%ST* %s) {
3385entry:
3386 %reg = getelementptr %ST* %s, i32 1, i32 2, i32 1, i32 5, i32 13
3387 ret i32* %reg
3388}
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3389</pre>
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]3390</div>
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3391
Chris Lattner7faa8832002-04-14 06:13:44 +0000[diff] [blame]3392<h5>Semantics:</h5>
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3393
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3394<p>In the example above, the first index is indexing into the '<tt>%ST*</tt>'
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3395type, which is a pointer, yielding a '<tt>%ST</tt>' = '<tt>{ i32, double, %RT
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3396}</tt>' type, a structure. The second index indexes into the third element of
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3397the structure, yielding a '<tt>%RT</tt>' = '<tt>{ i8 , [10 x [20 x i32]],
3398i8 }</tt>' type, another structure. The third index indexes into the second
3399element of the structure, yielding a '<tt>[10 x [20 x i32]]</tt>' type, an
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3400array. The two dimensions of the array are subscripted into, yielding an
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3401'<tt>i32</tt>' type. The '<tt>getelementptr</tt>' instruction returns a pointer
3402to this element, thus computing a value of '<tt>i32*</tt>' type.</p>
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3403
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]3404<p>Note that it is perfectly legal to index partially through a
3405structure, returning a pointer to an inner element. Because of this,
3406the LLVM code for the given testcase is equivalent to:</p>
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3407
3408<pre>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3409 define i32* %foo(%ST* %s) {
3410 %t1 = getelementptr %ST* %s, i32 1 <i>; yields %ST*:%t1</i>
Jeff Cohen6f1cc772007-04-22 01:17:39 +0000[diff] [blame]3411 %t2 = getelementptr %ST* %t1, i32 0, i32 2 <i>; yields %RT*:%t2</i>
3412 %t3 = getelementptr %RT* %t2, i32 0, i32 1 <i>; yields [10 x [20 x i32]]*:%t3</i>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3413 %t4 = getelementptr [10 x [20 x i32]]* %t3, i32 0, i32 5 <i>; yields [20 x i32]*:%t4</i>
3414 %t5 = getelementptr [20 x i32]* %t4, i32 0, i32 13 <i>; yields i32*:%t5</i>
3415 ret i32* %t5
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3416 }
Chris Lattner6536cfe2002-05-06 22:08:29 +0000[diff] [blame]3417</pre>
Chris Lattnere67a9512005-06-24 17:22:57 +0000[diff] [blame]3418
3419<p>Note that it is undefined to access an array out of bounds: array and
3420pointer indexes must always be within the defined bounds of the array type.
Chris Lattner05d67092008-04-24 05:59:56 +0000[diff] [blame]3421The one exception for this rule is zero length arrays. These arrays are
Chris Lattnere67a9512005-06-24 17:22:57 +0000[diff] [blame]3422defined to be accessible as variable length arrays, which requires access
3423beyond the zero'th element.</p>
3424
Chris Lattner884a9702006-08-15 00:45:58 +0000[diff] [blame]3425<p>The getelementptr instruction is often confusing. For some more insight
3426into how it works, see <a href="GetElementPtr.html">the getelementptr
3427FAQ</a>.</p>
3428
Chris Lattner7faa8832002-04-14 06:13:44 +0000[diff] [blame]3429<h5>Example:</h5>
Chris Lattnere67a9512005-06-24 17:22:57 +0000[diff] [blame]3430
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3431<pre>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3432 <i>; yields [12 x i8]*:aptr</i>
Matthijs Kooijmane49d0bc2008-10-13 13:44:15 +0000[diff] [blame]3433 %aptr = getelementptr {i32, [12 x i8]}* %saptr, i64 0, i32 1
3434 <i>; yields i8*:vptr</i>
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]3435 %vptr = getelementptr {i32, &lt;2 x i8&gt;}* %svptr, i64 0, i32 1, i32 1
Matthijs Kooijmane49d0bc2008-10-13 13:44:15 +0000[diff] [blame]3436 <i>; yields i8*:eptr</i>
3437 %eptr = getelementptr [12 x i8]* %aptr, i64 0, i32 1
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3438</pre>
Chris Lattnerf74d5c72004-04-05 01:30:49 +0000[diff] [blame]3439</div>
Reid Spencer47ce1792006-11-09 21:15:49 +0000[diff] [blame]3440
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]3441<!-- ======================================================================= -->
Reid Spencer2fd21e62006-11-08 01:18:52 +0000[diff] [blame]3442<div class="doc_subsection"> <a name="convertops">Conversion Operations</a>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3443</div>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3444<div class="doc_text">
Reid Spencer2fd21e62006-11-08 01:18:52 +0000[diff] [blame]3445<p>The instructions in this category are the conversion instructions (casting)
3446which all take a single operand and a type. They perform various bit conversions
3447on the operand.</p>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3448</div>
Chris Lattnercc37aae2004-03-12 05:50:16 +0000[diff] [blame]3449
Chris Lattner6536cfe2002-05-06 22:08:29 +0000[diff] [blame]3450<!-- _______________________________________________________________________ -->
Chris Lattnercc37aae2004-03-12 05:50:16 +0000[diff] [blame]3451<div class="doc_subsubsection">
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3452 <a name="i_trunc">'<tt>trunc .. to</tt>' Instruction</a>
3453</div>
3454<div class="doc_text">
3455
3456<h5>Syntax:</h5>
3457<pre>
3458 &lt;result&gt; = trunc &lt;ty&gt; &lt;value&gt; to &lt;ty2&gt; <i>; yields ty2</i>
3459</pre>
3460
3461<h5>Overview:</h5>
3462<p>
3463The '<tt>trunc</tt>' instruction truncates its operand to the type <tt>ty2</tt>.
3464</p>
3465
3466<h5>Arguments:</h5>
3467<p>
3468The '<tt>trunc</tt>' instruction takes a <tt>value</tt> to trunc, which must
3469be an <a href="#t_integer">integer</a> type, and a type that specifies the size
Chris Lattner3b19d652007-01-15 01:54:13 +0000[diff] [blame]3470and type of the result, which must be an <a href="#t_integer">integer</a>
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]3471type. The bit size of <tt>value</tt> must be larger than the bit size of
3472<tt>ty2</tt>. Equal sized types are not allowed.</p>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3473
3474<h5>Semantics:</h5>
3475<p>
3476The '<tt>trunc</tt>' instruction truncates the high order bits in <tt>value</tt>
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]3477and converts the remaining bits to <tt>ty2</tt>. Since the source size must be
3478larger than the destination size, <tt>trunc</tt> cannot be a <i>no-op cast</i>.
3479It will always truncate bits.</p>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3480
3481<h5>Example:</h5>
3482<pre>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3483 %X = trunc i32 257 to i8 <i>; yields i8:1</i>
Reid Spencerc78f3372007-01-12 03:35:51 +0000[diff] [blame]3484 %Y = trunc i32 123 to i1 <i>; yields i1:true</i>
3485 %Y = trunc i32 122 to i1 <i>; yields i1:false</i>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3486</pre>
3487</div>
3488
3489<!-- _______________________________________________________________________ -->
3490<div class="doc_subsubsection">
3491 <a name="i_zext">'<tt>zext .. to</tt>' Instruction</a>
3492</div>
3493<div class="doc_text">
3494
3495<h5>Syntax:</h5>
3496<pre>
3497 &lt;result&gt; = zext &lt;ty&gt; &lt;value&gt; to &lt;ty2&gt; <i>; yields ty2</i>
3498</pre>
3499
3500<h5>Overview:</h5>
3501<p>The '<tt>zext</tt>' instruction zero extends its operand to type
3502<tt>ty2</tt>.</p>
3503
3504
3505<h5>Arguments:</h5>
3506<p>The '<tt>zext</tt>' instruction takes a value to cast, which must be of
Chris Lattner3b19d652007-01-15 01:54:13 +0000[diff] [blame]3507<a href="#t_integer">integer</a> type, and a type to cast it to, which must
3508also be of <a href="#t_integer">integer</a> type. The bit size of the
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]3509<tt>value</tt> must be smaller than the bit size of the destination type,
3510<tt>ty2</tt>.</p>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3511
3512<h5>Semantics:</h5>
3513<p>The <tt>zext</tt> fills the high order bits of the <tt>value</tt> with zero
Chris Lattnerd1d25172007-05-24 19:13:27 +0000[diff] [blame]3514bits until it reaches the size of the destination type, <tt>ty2</tt>.</p>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3515
Reid Spencerb5929522007-01-12 15:46:11 +0000[diff] [blame]3516<p>When zero extending from i1, the result will always be either 0 or 1.</p>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3517
3518<h5>Example:</h5>
3519<pre>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3520 %X = zext i32 257 to i64 <i>; yields i64:257</i>
Reid Spencerc78f3372007-01-12 03:35:51 +0000[diff] [blame]3521 %Y = zext i1 true to i32 <i>; yields i32:1</i>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3522</pre>
3523</div>
3524
3525<!-- _______________________________________________________________________ -->
3526<div class="doc_subsubsection">
3527 <a name="i_sext">'<tt>sext .. to</tt>' Instruction</a>
3528</div>
3529<div class="doc_text">
3530
3531<h5>Syntax:</h5>
3532<pre>
3533 &lt;result&gt; = sext &lt;ty&gt; &lt;value&gt; to &lt;ty2&gt; <i>; yields ty2</i>
3534</pre>
3535
3536<h5>Overview:</h5>
3537<p>The '<tt>sext</tt>' sign extends <tt>value</tt> to the type <tt>ty2</tt>.</p>
3538
3539<h5>Arguments:</h5>
3540<p>
3541The '<tt>sext</tt>' instruction takes a value to cast, which must be of
Chris Lattner3b19d652007-01-15 01:54:13 +0000[diff] [blame]3542<a href="#t_integer">integer</a> type, and a type to cast it to, which must
3543also be of <a href="#t_integer">integer</a> type. The bit size of the
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]3544<tt>value</tt> must be smaller than the bit size of the destination type,
3545<tt>ty2</tt>.</p>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3546
3547<h5>Semantics:</h5>
3548<p>
3549The '<tt>sext</tt>' instruction performs a sign extension by copying the sign
3550bit (highest order bit) of the <tt>value</tt> until it reaches the bit size of
Chris Lattnerd1d25172007-05-24 19:13:27 +0000[diff] [blame]3551the type <tt>ty2</tt>.</p>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3552
Reid Spencerc78f3372007-01-12 03:35:51 +0000[diff] [blame]3553<p>When sign extending from i1, the extension always results in -1 or 0.</p>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3554
3555<h5>Example:</h5>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3556<pre>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3557 %X = sext i8 -1 to i16 <i>; yields i16 :65535</i>
Reid Spencerc78f3372007-01-12 03:35:51 +0000[diff] [blame]3558 %Y = sext i1 true to i32 <i>; yields i32:-1</i>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3559</pre>
3560</div>
3561
3562<!-- _______________________________________________________________________ -->
3563<div class="doc_subsubsection">
Reid Spencer3fa91b02006-11-09 21:48:10 +0000[diff] [blame]3564 <a name="i_fptrunc">'<tt>fptrunc .. to</tt>' Instruction</a>
3565</div>
3566
3567<div class="doc_text">
3568
3569<h5>Syntax:</h5>
3570
3571<pre>
3572 &lt;result&gt; = fptrunc &lt;ty&gt; &lt;value&gt; to &lt;ty2&gt; <i>; yields ty2</i>
3573</pre>
3574
3575<h5>Overview:</h5>
3576<p>The '<tt>fptrunc</tt>' instruction truncates <tt>value</tt> to type
3577<tt>ty2</tt>.</p>
3578
3579
3580<h5>Arguments:</h5>
3581<p>The '<tt>fptrunc</tt>' instruction takes a <a href="#t_floating">floating
3582 point</a> value to cast and a <a href="#t_floating">floating point</a> type to
3583cast it to. The size of <tt>value</tt> must be larger than the size of
3584<tt>ty2</tt>. This implies that <tt>fptrunc</tt> cannot be used to make a
3585<i>no-op cast</i>.</p>
3586
3587<h5>Semantics:</h5>
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]3588<p> The '<tt>fptrunc</tt>' instruction truncates a <tt>value</tt> from a larger
3589<a href="#t_floating">floating point</a> type to a smaller
3590<a href="#t_floating">floating point</a> type. If the value cannot fit within
3591the destination type, <tt>ty2</tt>, then the results are undefined.</p>
Reid Spencer3fa91b02006-11-09 21:48:10 +0000[diff] [blame]3592
3593<h5>Example:</h5>
3594<pre>
3595 %X = fptrunc double 123.0 to float <i>; yields float:123.0</i>
3596 %Y = fptrunc double 1.0E+300 to float <i>; yields undefined</i>
3597</pre>
3598</div>
3599
3600<!-- _______________________________________________________________________ -->
3601<div class="doc_subsubsection">
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3602 <a name="i_fpext">'<tt>fpext .. to</tt>' Instruction</a>
3603</div>
3604<div class="doc_text">
3605
3606<h5>Syntax:</h5>
3607<pre>
3608 &lt;result&gt; = fpext &lt;ty&gt; &lt;value&gt; to &lt;ty2&gt; <i>; yields ty2</i>
3609</pre>
3610
3611<h5>Overview:</h5>
3612<p>The '<tt>fpext</tt>' extends a floating point <tt>value</tt> to a larger
3613floating point value.</p>
3614
3615<h5>Arguments:</h5>
3616<p>The '<tt>fpext</tt>' instruction takes a
3617<a href="#t_floating">floating point</a> <tt>value</tt> to cast,
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]3618and a <a href="#t_floating">floating point</a> type to cast it to. The source
3619type must be smaller than the destination type.</p>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3620
3621<h5>Semantics:</h5>
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]3622<p>The '<tt>fpext</tt>' instruction extends the <tt>value</tt> from a smaller
Duncan Sands8036ca42007-03-30 12:22:09 +0000[diff] [blame]3623<a href="#t_floating">floating point</a> type to a larger
3624<a href="#t_floating">floating point</a> type. The <tt>fpext</tt> cannot be
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]3625used to make a <i>no-op cast</i> because it always changes bits. Use
Reid Spencer5c0ef472006-11-11 23:08:07 +0000[diff] [blame]3626<tt>bitcast</tt> to make a <i>no-op cast</i> for a floating point cast.</p>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3627
3628<h5>Example:</h5>
3629<pre>
3630 %X = fpext float 3.1415 to double <i>; yields double:3.1415</i>
3631 %Y = fpext float 1.0 to float <i>; yields float:1.0 (no-op)</i>
3632</pre>
3633</div>
3634
3635<!-- _______________________________________________________________________ -->
3636<div class="doc_subsubsection">
Reid Spencer24d6da52007-01-21 00:29:26 +0000[diff] [blame]3637 <a name="i_fptoui">'<tt>fptoui .. to</tt>' Instruction</a>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3638</div>
3639<div class="doc_text">
3640
3641<h5>Syntax:</h5>
3642<pre>
Reid Spencer1539a1c2007-07-31 14:40:14 +0000[diff] [blame]3643 &lt;result&gt; = fptoui &lt;ty&gt; &lt;value&gt; to &lt;ty2&gt; <i>; yields ty2</i>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3644</pre>
3645
3646<h5>Overview:</h5>
Reid Spencer1539a1c2007-07-31 14:40:14 +0000[diff] [blame]3647<p>The '<tt>fptoui</tt>' converts a floating point <tt>value</tt> to its
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3648unsigned integer equivalent of type <tt>ty2</tt>.
3649</p>
3650
3651<h5>Arguments:</h5>
Reid Spencer1539a1c2007-07-31 14:40:14 +0000[diff] [blame]3652<p>The '<tt>fptoui</tt>' instruction takes a value to cast, which must be a
Nate Begemanb348d182007-11-17 03:58:34 +0000[diff] [blame]3653scalar or vector <a href="#t_floating">floating point</a> value, and a type
3654to cast it to <tt>ty2</tt>, which must be an <a href="#t_integer">integer</a>
3655type. If <tt>ty</tt> is a vector floating point type, <tt>ty2</tt> must be a
3656vector integer type with the same number of elements as <tt>ty</tt></p>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3657
3658<h5>Semantics:</h5>
Reid Spencer1539a1c2007-07-31 14:40:14 +0000[diff] [blame]3659<p> The '<tt>fptoui</tt>' instruction converts its
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3660<a href="#t_floating">floating point</a> operand into the nearest (rounding
3661towards zero) unsigned integer value. If the value cannot fit in <tt>ty2</tt>,
3662the results are undefined.</p>
3663
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3664<h5>Example:</h5>
3665<pre>
Reid Spencer1539a1c2007-07-31 14:40:14 +0000[diff] [blame]3666 %X = fptoui double 123.0 to i32 <i>; yields i32:123</i>
Chris Lattner88519042007-09-22 03:17:52 +0000[diff] [blame]3667 %Y = fptoui float 1.0E+300 to i1 <i>; yields undefined:1</i>
Reid Spencer1539a1c2007-07-31 14:40:14 +0000[diff] [blame]3668 %X = fptoui float 1.04E+17 to i8 <i>; yields undefined:1</i>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3669</pre>
3670</div>
3671
3672<!-- _______________________________________________________________________ -->
3673<div class="doc_subsubsection">
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]3674 <a name="i_fptosi">'<tt>fptosi .. to</tt>' Instruction</a>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3675</div>
3676<div class="doc_text">
3677
3678<h5>Syntax:</h5>
3679<pre>
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]3680 &lt;result&gt; = fptosi &lt;ty&gt; &lt;value&gt; to &lt;ty2&gt; <i>; yields ty2</i>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3681</pre>
3682
3683<h5>Overview:</h5>
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]3684<p>The '<tt>fptosi</tt>' instruction converts
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3685<a href="#t_floating">floating point</a> <tt>value</tt> to type <tt>ty2</tt>.
Chris Lattnercc37aae2004-03-12 05:50:16 +0000[diff] [blame]3686</p>
3687
Chris Lattner6536cfe2002-05-06 22:08:29 +0000[diff] [blame]3688<h5>Arguments:</h5>
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]3689<p> The '<tt>fptosi</tt>' instruction takes a value to cast, which must be a
Nate Begemanb348d182007-11-17 03:58:34 +0000[diff] [blame]3690scalar or vector <a href="#t_floating">floating point</a> value, and a type
3691to cast it to <tt>ty2</tt>, which must be an <a href="#t_integer">integer</a>
3692type. If <tt>ty</tt> is a vector floating point type, <tt>ty2</tt> must be a
3693vector integer type with the same number of elements as <tt>ty</tt></p>
Chris Lattnercc37aae2004-03-12 05:50:16 +0000[diff] [blame]3694
Chris Lattner6536cfe2002-05-06 22:08:29 +0000[diff] [blame]3695<h5>Semantics:</h5>
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]3696<p>The '<tt>fptosi</tt>' instruction converts its
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3697<a href="#t_floating">floating point</a> operand into the nearest (rounding
3698towards zero) signed integer value. If the value cannot fit in <tt>ty2</tt>,
3699the results are undefined.</p>
Chris Lattnercc37aae2004-03-12 05:50:16 +0000[diff] [blame]3700
Chris Lattner33ba0d92001-07-09 00:26:23 +0000[diff] [blame]3701<h5>Example:</h5>
Chris Lattnercc37aae2004-03-12 05:50:16 +0000[diff] [blame]3702<pre>
Reid Spencerc78f3372007-01-12 03:35:51 +0000[diff] [blame]3703 %X = fptosi double -123.0 to i32 <i>; yields i32:-123</i>
Chris Lattner88519042007-09-22 03:17:52 +0000[diff] [blame]3704 %Y = fptosi float 1.0E-247 to i1 <i>; yields undefined:1</i>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3705 %X = fptosi float 1.04E+17 to i8 <i>; yields undefined:1</i>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3706</pre>
3707</div>
3708
3709<!-- _______________________________________________________________________ -->
3710<div class="doc_subsubsection">
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]3711 <a name="i_uitofp">'<tt>uitofp .. to</tt>' Instruction</a>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3712</div>
3713<div class="doc_text">
3714
3715<h5>Syntax:</h5>
3716<pre>
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]3717 &lt;result&gt; = uitofp &lt;ty&gt; &lt;value&gt; to &lt;ty2&gt; <i>; yields ty2</i>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3718</pre>
3719
3720<h5>Overview:</h5>
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]3721<p>The '<tt>uitofp</tt>' instruction regards <tt>value</tt> as an unsigned
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3722integer and converts that value to the <tt>ty2</tt> type.</p>
3723
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3724<h5>Arguments:</h5>
Nate Begemanb348d182007-11-17 03:58:34 +0000[diff] [blame]3725<p>The '<tt>uitofp</tt>' instruction takes a value to cast, which must be a
3726scalar or vector <a href="#t_integer">integer</a> value, and a type to cast it
3727to <tt>ty2</tt>, which must be an <a href="#t_floating">floating point</a>
3728type. If <tt>ty</tt> is a vector integer type, <tt>ty2</tt> must be a vector
3729floating point type with the same number of elements as <tt>ty</tt></p>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3730
3731<h5>Semantics:</h5>
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]3732<p>The '<tt>uitofp</tt>' instruction interprets its operand as an unsigned
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3733integer quantity and converts it to the corresponding floating point value. If
Jeff Cohencb757312007-04-22 14:56:37 +0000[diff] [blame]3734the value cannot fit in the floating point value, the results are undefined.</p>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3735
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3736<h5>Example:</h5>
3737<pre>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3738 %X = uitofp i32 257 to float <i>; yields float:257.0</i>
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]3739 %Y = uitofp i8 -1 to double <i>; yields double:255.0</i>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3740</pre>
3741</div>
3742
3743<!-- _______________________________________________________________________ -->
3744<div class="doc_subsubsection">
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]3745 <a name="i_sitofp">'<tt>sitofp .. to</tt>' Instruction</a>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3746</div>
3747<div class="doc_text">
3748
3749<h5>Syntax:</h5>
3750<pre>
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]3751 &lt;result&gt; = sitofp &lt;ty&gt; &lt;value&gt; to &lt;ty2&gt; <i>; yields ty2</i>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3752</pre>
3753
3754<h5>Overview:</h5>
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]3755<p>The '<tt>sitofp</tt>' instruction regards <tt>value</tt> as a signed
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3756integer and converts that value to the <tt>ty2</tt> type.</p>
3757
3758<h5>Arguments:</h5>
Nate Begemanb348d182007-11-17 03:58:34 +0000[diff] [blame]3759<p>The '<tt>sitofp</tt>' instruction takes a value to cast, which must be a
3760scalar or vector <a href="#t_integer">integer</a> value, and a type to cast it
3761to <tt>ty2</tt>, which must be an <a href="#t_floating">floating point</a>
3762type. If <tt>ty</tt> is a vector integer type, <tt>ty2</tt> must be a vector
3763floating point type with the same number of elements as <tt>ty</tt></p>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3764
3765<h5>Semantics:</h5>
Reid Spencerd4448792006-11-09 23:03:26 +0000[diff] [blame]3766<p>The '<tt>sitofp</tt>' instruction interprets its operand as a signed
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3767integer quantity and converts it to the corresponding floating point value. If
Jeff Cohencb757312007-04-22 14:56:37 +0000[diff] [blame]3768the value cannot fit in the floating point value, the results are undefined.</p>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3769
3770<h5>Example:</h5>
3771<pre>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3772 %X = sitofp i32 257 to float <i>; yields float:257.0</i>
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]3773 %Y = sitofp i8 -1 to double <i>; yields double:-1.0</i>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3774</pre>
3775</div>
3776
3777<!-- _______________________________________________________________________ -->
3778<div class="doc_subsubsection">
Reid Spencer72679252006-11-11 21:00:47 +0000[diff] [blame]3779 <a name="i_ptrtoint">'<tt>ptrtoint .. to</tt>' Instruction</a>
3780</div>
3781<div class="doc_text">
3782
3783<h5>Syntax:</h5>
3784<pre>
3785 &lt;result&gt; = ptrtoint &lt;ty&gt; &lt;value&gt; to &lt;ty2&gt; <i>; yields ty2</i>
3786</pre>
3787
3788<h5>Overview:</h5>
3789<p>The '<tt>ptrtoint</tt>' instruction converts the pointer <tt>value</tt> to
3790the integer type <tt>ty2</tt>.</p>
3791
3792<h5>Arguments:</h5>
3793<p>The '<tt>ptrtoint</tt>' instruction takes a <tt>value</tt> to cast, which
Duncan Sands8036ca42007-03-30 12:22:09 +0000[diff] [blame]3794must be a <a href="#t_pointer">pointer</a> value, and a type to cast it to
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]3795<tt>ty2</tt>, which must be an <a href="#t_integer">integer</a> type.</p>
Reid Spencer72679252006-11-11 21:00:47 +0000[diff] [blame]3796
3797<h5>Semantics:</h5>
3798<p>The '<tt>ptrtoint</tt>' instruction converts <tt>value</tt> to integer type
3799<tt>ty2</tt> by interpreting the pointer value as an integer and either
3800truncating or zero extending that value to the size of the integer type. If
3801<tt>value</tt> is smaller than <tt>ty2</tt> then a zero extension is done. If
3802<tt>value</tt> is larger than <tt>ty2</tt> then a truncation is done. If they
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]3803are the same size, then nothing is done (<i>no-op cast</i>) other than a type
3804change.</p>
Reid Spencer72679252006-11-11 21:00:47 +0000[diff] [blame]3805
3806<h5>Example:</h5>
3807<pre>
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]3808 %X = ptrtoint i32* %X to i8 <i>; yields truncation on 32-bit architecture</i>
3809 %Y = ptrtoint i32* %x to i64 <i>; yields zero extension on 32-bit architecture</i>
Reid Spencer72679252006-11-11 21:00:47 +0000[diff] [blame]3810</pre>
3811</div>
3812
3813<!-- _______________________________________________________________________ -->
3814<div class="doc_subsubsection">
3815 <a name="i_inttoptr">'<tt>inttoptr .. to</tt>' Instruction</a>
3816</div>
3817<div class="doc_text">
3818
3819<h5>Syntax:</h5>
3820<pre>
3821 &lt;result&gt; = inttoptr &lt;ty&gt; &lt;value&gt; to &lt;ty2&gt; <i>; yields ty2</i>
3822</pre>
3823
3824<h5>Overview:</h5>
3825<p>The '<tt>inttoptr</tt>' instruction converts an integer <tt>value</tt> to
3826a pointer type, <tt>ty2</tt>.</p>
3827
3828<h5>Arguments:</h5>
Duncan Sands8036ca42007-03-30 12:22:09 +0000[diff] [blame]3829<p>The '<tt>inttoptr</tt>' instruction takes an <a href="#t_integer">integer</a>
Reid Spencer72679252006-11-11 21:00:47 +0000[diff] [blame]3830value to cast, and a type to cast it to, which must be a
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]3831<a href="#t_pointer">pointer</a> type.</p>
Reid Spencer72679252006-11-11 21:00:47 +0000[diff] [blame]3832
3833<h5>Semantics:</h5>
3834<p>The '<tt>inttoptr</tt>' instruction converts <tt>value</tt> to type
3835<tt>ty2</tt> by applying either a zero extension or a truncation depending on
3836the size of the integer <tt>value</tt>. If <tt>value</tt> is larger than the
3837size of a pointer then a truncation is done. If <tt>value</tt> is smaller than
3838the size of a pointer then a zero extension is done. If they are the same size,
3839nothing is done (<i>no-op cast</i>).</p>
3840
3841<h5>Example:</h5>
3842<pre>
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]3843 %X = inttoptr i32 255 to i32* <i>; yields zero extension on 64-bit architecture</i>
3844 %X = inttoptr i32 255 to i32* <i>; yields no-op on 32-bit architecture</i>
3845 %Y = inttoptr i64 0 to i32* <i>; yields truncation on 32-bit architecture</i>
Reid Spencer72679252006-11-11 21:00:47 +0000[diff] [blame]3846</pre>
3847</div>
3848
3849<!-- _______________________________________________________________________ -->
3850<div class="doc_subsubsection">
Reid Spencer5c0ef472006-11-11 23:08:07 +0000[diff] [blame]3851 <a name="i_bitcast">'<tt>bitcast .. to</tt>' Instruction</a>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3852</div>
3853<div class="doc_text">
3854
3855<h5>Syntax:</h5>
3856<pre>
Reid Spencer5c0ef472006-11-11 23:08:07 +0000[diff] [blame]3857 &lt;result&gt; = bitcast &lt;ty&gt; &lt;value&gt; to &lt;ty2&gt; <i>; yields ty2</i>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3858</pre>
3859
3860<h5>Overview:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]3861
Reid Spencer5c0ef472006-11-11 23:08:07 +0000[diff] [blame]3862<p>The '<tt>bitcast</tt>' instruction converts <tt>value</tt> to type
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3863<tt>ty2</tt> without changing any bits.</p>
3864
3865<h5>Arguments:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]3866
Reid Spencer5c0ef472006-11-11 23:08:07 +0000[diff] [blame]3867<p>The '<tt>bitcast</tt>' instruction takes a value to cast, which must be
Dan Gohman500233a2008-09-08 16:45:59 +0000[diff] [blame]3868a non-aggregate first class value, and a type to cast it to, which must also be
3869a non-aggregate <a href="#t_firstclass">first class</a> type. The bit sizes of
3870<tt>value</tt>
Reid Spencer19b569f2007-01-09 20:08:58 +0000[diff] [blame]3871and the destination type, <tt>ty2</tt>, must be identical. If the source
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]3872type is a pointer, the destination type must also be a pointer. This
3873instruction supports bitwise conversion of vectors to integers and to vectors
3874of other types (as long as they have the same size).</p>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3875
3876<h5>Semantics:</h5>
Reid Spencer5c0ef472006-11-11 23:08:07 +0000[diff] [blame]3877<p>The '<tt>bitcast</tt>' instruction converts <tt>value</tt> to type
Reid Spencer72679252006-11-11 21:00:47 +0000[diff] [blame]3878<tt>ty2</tt>. It is always a <i>no-op cast</i> because no bits change with
3879this conversion. The conversion is done as if the <tt>value</tt> had been
3880stored to memory and read back as type <tt>ty2</tt>. Pointer types may only be
3881converted to other pointer types with this instruction. To convert pointers to
3882other types, use the <a href="#i_inttoptr">inttoptr</a> or
3883<a href="#i_ptrtoint">ptrtoint</a> instructions first.</p>
Reid Spencer9dee3ac2006-11-08 01:11:31 +0000[diff] [blame]3884
3885<h5>Example:</h5>
3886<pre>
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]3887 %X = bitcast i8 255 to i8 <i>; yields i8 :-1</i>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3888 %Y = bitcast i32* %x to sint* <i>; yields sint*:%x</i>
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]3889 %Z = bitcast &lt;2 x int&gt; %V to i64; <i>; yields i64: %V</i>
Chris Lattner33ba0d92001-07-09 00:26:23 +0000[diff] [blame]3890</pre>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]3891</div>
Chris Lattnercc37aae2004-03-12 05:50:16 +0000[diff] [blame]3892
Reid Spencer2fd21e62006-11-08 01:18:52 +0000[diff] [blame]3893<!-- ======================================================================= -->
3894<div class="doc_subsection"> <a name="otherops">Other Operations</a> </div>
3895<div class="doc_text">
3896<p>The instructions in this category are the "miscellaneous"
3897instructions, which defy better classification.</p>
3898</div>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]3899
3900<!-- _______________________________________________________________________ -->
3901<div class="doc_subsubsection"><a name="i_icmp">'<tt>icmp</tt>' Instruction</a>
3902</div>
3903<div class="doc_text">
3904<h5>Syntax:</h5>
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]3905<pre> &lt;result&gt; = icmp &lt;cond&gt; &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {i1} or {&lt;N x i1&gt;}:result</i>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]3906</pre>
3907<h5>Overview:</h5>
Dan Gohmanf72fb672008-09-09 01:02:47 +0000[diff] [blame]3908<p>The '<tt>icmp</tt>' instruction returns a boolean value or
3909a vector of boolean values based on comparison
3910of its two integer, integer vector, or pointer operands.</p>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]3911<h5>Arguments:</h5>
3912<p>The '<tt>icmp</tt>' instruction takes three operands. The first operand is
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]3913the condition code indicating the kind of comparison to perform. It is not
3914a value, just a keyword. The possible condition code are:
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]3915</p>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]3916<ol>
3917 <li><tt>eq</tt>: equal</li>
3918 <li><tt>ne</tt>: not equal </li>
3919 <li><tt>ugt</tt>: unsigned greater than</li>
3920 <li><tt>uge</tt>: unsigned greater or equal</li>
3921 <li><tt>ult</tt>: unsigned less than</li>
3922 <li><tt>ule</tt>: unsigned less or equal</li>
3923 <li><tt>sgt</tt>: signed greater than</li>
3924 <li><tt>sge</tt>: signed greater or equal</li>
3925 <li><tt>slt</tt>: signed less than</li>
3926 <li><tt>sle</tt>: signed less or equal</li>
3927</ol>
Chris Lattner3b19d652007-01-15 01:54:13 +0000[diff] [blame]3928<p>The remaining two arguments must be <a href="#t_integer">integer</a> or
Dan Gohmanf72fb672008-09-09 01:02:47 +0000[diff] [blame]3929<a href="#t_pointer">pointer</a>
3930or integer <a href="#t_vector">vector</a> typed.
3931They must also be identical types.</p>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]3932<h5>Semantics:</h5>
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]3933<p>The '<tt>icmp</tt>' compares <tt>op1</tt> and <tt>op2</tt> according to
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]3934the condition code given as <tt>cond</tt>. The comparison performed always
Dan Gohmanf72fb672008-09-09 01:02:47 +0000[diff] [blame]3935yields either an <a href="#t_primitive"><tt>i1</tt></a> or vector of <tt>i1</tt> result, as follows:
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]3936</p>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]3937<ol>
3938 <li><tt>eq</tt>: yields <tt>true</tt> if the operands are equal,
3939 <tt>false</tt> otherwise. No sign interpretation is necessary or performed.
3940 </li>
3941 <li><tt>ne</tt>: yields <tt>true</tt> if the operands are unequal,
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]3942 <tt>false</tt> otherwise. No sign interpretation is necessary or performed.</li>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]3943 <li><tt>ugt</tt>: interprets the operands as unsigned values and yields
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]3944 <tt>true</tt> if <tt>op1</tt> is greater than <tt>op2</tt>.</li>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]3945 <li><tt>uge</tt>: interprets the operands as unsigned values and yields
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]3946 <tt>true</tt> if <tt>op1</tt> is greater than or equal to <tt>op2</tt>.</li>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]3947 <li><tt>ult</tt>: interprets the operands as unsigned values and yields
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]3948 <tt>true</tt> if <tt>op1</tt> is less than <tt>op2</tt>.</li>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]3949 <li><tt>ule</tt>: interprets the operands as unsigned values and yields
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]3950 <tt>true</tt> if <tt>op1</tt> is less than or equal to <tt>op2</tt>.</li>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]3951 <li><tt>sgt</tt>: interprets the operands as signed values and yields
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]3952 <tt>true</tt> if <tt>op1</tt> is greater than <tt>op2</tt>.</li>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]3953 <li><tt>sge</tt>: interprets the operands as signed values and yields
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]3954 <tt>true</tt> if <tt>op1</tt> is greater than or equal to <tt>op2</tt>.</li>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]3955 <li><tt>slt</tt>: interprets the operands as signed values and yields
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]3956 <tt>true</tt> if <tt>op1</tt> is less than <tt>op2</tt>.</li>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]3957 <li><tt>sle</tt>: interprets the operands as signed values and yields
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]3958 <tt>true</tt> if <tt>op1</tt> is less than or equal to <tt>op2</tt>.</li>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]3959</ol>
3960<p>If the operands are <a href="#t_pointer">pointer</a> typed, the pointer
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]3961values are compared as if they were integers.</p>
Dan Gohmanf72fb672008-09-09 01:02:47 +0000[diff] [blame]3962<p>If the operands are integer vectors, then they are compared
3963element by element. The result is an <tt>i1</tt> vector with
3964the same number of elements as the values being compared.
3965Otherwise, the result is an <tt>i1</tt>.
3966</p>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]3967
3968<h5>Example:</h5>
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]3969<pre> &lt;result&gt; = icmp eq i32 4, 5 <i>; yields: result=false</i>
3970 &lt;result&gt; = icmp ne float* %X, %X <i>; yields: result=false</i>
3971 &lt;result&gt; = icmp ult i16 4, 5 <i>; yields: result=true</i>
3972 &lt;result&gt; = icmp sgt i16 4, 5 <i>; yields: result=false</i>
3973 &lt;result&gt; = icmp ule i16 -4, 5 <i>; yields: result=false</i>
3974 &lt;result&gt; = icmp sge i16 4, 5 <i>; yields: result=false</i>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]3975</pre>
3976</div>
3977
3978<!-- _______________________________________________________________________ -->
3979<div class="doc_subsubsection"><a name="i_fcmp">'<tt>fcmp</tt>' Instruction</a>
3980</div>
3981<div class="doc_text">
3982<h5>Syntax:</h5>
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]3983<pre> &lt;result&gt; = fcmp &lt;cond&gt; &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {i1} or {&lt;N x i1&gt;}:result</i>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]3984</pre>
3985<h5>Overview:</h5>
Dan Gohmanf72fb672008-09-09 01:02:47 +0000[diff] [blame]3986<p>The '<tt>fcmp</tt>' instruction returns a boolean value
3987or vector of boolean values based on comparison
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]3988of its operands.</p>
Dan Gohmanf72fb672008-09-09 01:02:47 +0000[diff] [blame]3989<p>
3990If the operands are floating point scalars, then the result
3991type is a boolean (<a href="#t_primitive"><tt>i1</tt></a>).
3992</p>
3993<p>If the operands are floating point vectors, then the result type
3994is a vector of boolean with the same number of elements as the
3995operands being compared.</p>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]3996<h5>Arguments:</h5>
3997<p>The '<tt>fcmp</tt>' instruction takes three operands. The first operand is
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]3998the condition code indicating the kind of comparison to perform. It is not
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]3999a value, just a keyword. The possible condition code are:</p>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]4000<ol>
Reid Spencerb7f26282006-11-19 03:00:14 +0000[diff] [blame]4001 <li><tt>false</tt>: no comparison, always returns false</li>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]4002 <li><tt>oeq</tt>: ordered and equal</li>
4003 <li><tt>ogt</tt>: ordered and greater than </li>
4004 <li><tt>oge</tt>: ordered and greater than or equal</li>
4005 <li><tt>olt</tt>: ordered and less than </li>
4006 <li><tt>ole</tt>: ordered and less than or equal</li>
4007 <li><tt>one</tt>: ordered and not equal</li>
4008 <li><tt>ord</tt>: ordered (no nans)</li>
4009 <li><tt>ueq</tt>: unordered or equal</li>
4010 <li><tt>ugt</tt>: unordered or greater than </li>
4011 <li><tt>uge</tt>: unordered or greater than or equal</li>
4012 <li><tt>ult</tt>: unordered or less than </li>
4013 <li><tt>ule</tt>: unordered or less than or equal</li>
4014 <li><tt>une</tt>: unordered or not equal</li>
4015 <li><tt>uno</tt>: unordered (either nans)</li>
Reid Spencerb7f26282006-11-19 03:00:14 +0000[diff] [blame]4016 <li><tt>true</tt>: no comparison, always returns true</li>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]4017</ol>
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]4018<p><i>Ordered</i> means that neither operand is a QNAN while
Reid Spencer93a49852006-12-06 07:08:07 +0000[diff] [blame]4019<i>unordered</i> means that either operand may be a QNAN.</p>
Dan Gohmanf72fb672008-09-09 01:02:47 +0000[diff] [blame]4020<p>Each of <tt>val1</tt> and <tt>val2</tt> arguments must be
4021either a <a href="#t_floating">floating point</a> type
4022or a <a href="#t_vector">vector</a> of floating point type.
4023They must have identical types.</p>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]4024<h5>Semantics:</h5>
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]4025<p>The '<tt>fcmp</tt>' instruction compares <tt>op1</tt> and <tt>op2</tt>
Dan Gohmanf72fb672008-09-09 01:02:47 +0000[diff] [blame]4026according to the condition code given as <tt>cond</tt>.
4027If the operands are vectors, then the vectors are compared
4028element by element.
4029Each comparison performed
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]4030always yields an <a href="#t_primitive">i1</a> result, as follows:</p>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]4031<ol>
4032 <li><tt>false</tt>: always yields <tt>false</tt>, regardless of operands.</li>
Reid Spencerb7f26282006-11-19 03:00:14 +0000[diff] [blame]4033 <li><tt>oeq</tt>: yields <tt>true</tt> if both operands are not a QNAN and
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]4034 <tt>op1</tt> is equal to <tt>op2</tt>.</li>
Reid Spencerb7f26282006-11-19 03:00:14 +0000[diff] [blame]4035 <li><tt>ogt</tt>: yields <tt>true</tt> if both operands are not a QNAN and
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]4036 <tt>op1</tt> is greather than <tt>op2</tt>.</li>
Reid Spencerb7f26282006-11-19 03:00:14 +0000[diff] [blame]4037 <li><tt>oge</tt>: yields <tt>true</tt> if both operands are not a QNAN and
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]4038 <tt>op1</tt> is greater than or equal to <tt>op2</tt>.</li>
Reid Spencerb7f26282006-11-19 03:00:14 +0000[diff] [blame]4039 <li><tt>olt</tt>: yields <tt>true</tt> if both operands are not a QNAN and
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]4040 <tt>op1</tt> is less than <tt>op2</tt>.</li>
Reid Spencerb7f26282006-11-19 03:00:14 +0000[diff] [blame]4041 <li><tt>ole</tt>: yields <tt>true</tt> if both operands are not a QNAN and
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]4042 <tt>op1</tt> is less than or equal to <tt>op2</tt>.</li>
Reid Spencerb7f26282006-11-19 03:00:14 +0000[diff] [blame]4043 <li><tt>one</tt>: yields <tt>true</tt> if both operands are not a QNAN and
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]4044 <tt>op1</tt> is not equal to <tt>op2</tt>.</li>
Reid Spencerb7f26282006-11-19 03:00:14 +0000[diff] [blame]4045 <li><tt>ord</tt>: yields <tt>true</tt> if both operands are not a QNAN.</li>
4046 <li><tt>ueq</tt>: yields <tt>true</tt> if either operand is a QNAN or
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]4047 <tt>op1</tt> is equal to <tt>op2</tt>.</li>
Reid Spencerb7f26282006-11-19 03:00:14 +0000[diff] [blame]4048 <li><tt>ugt</tt>: yields <tt>true</tt> if either operand is a QNAN or
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]4049 <tt>op1</tt> is greater than <tt>op2</tt>.</li>
Reid Spencerb7f26282006-11-19 03:00:14 +0000[diff] [blame]4050 <li><tt>uge</tt>: yields <tt>true</tt> if either operand is a QNAN or
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]4051 <tt>op1</tt> is greater than or equal to <tt>op2</tt>.</li>
Reid Spencerb7f26282006-11-19 03:00:14 +0000[diff] [blame]4052 <li><tt>ult</tt>: yields <tt>true</tt> if either operand is a QNAN or
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]4053 <tt>op1</tt> is less than <tt>op2</tt>.</li>
Reid Spencerb7f26282006-11-19 03:00:14 +0000[diff] [blame]4054 <li><tt>ule</tt>: yields <tt>true</tt> if either operand is a QNAN or
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]4055 <tt>op1</tt> is less than or equal to <tt>op2</tt>.</li>
Reid Spencerb7f26282006-11-19 03:00:14 +0000[diff] [blame]4056 <li><tt>une</tt>: yields <tt>true</tt> if either operand is a QNAN or
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]4057 <tt>op1</tt> is not equal to <tt>op2</tt>.</li>
Reid Spencerb7f26282006-11-19 03:00:14 +0000[diff] [blame]4058 <li><tt>uno</tt>: yields <tt>true</tt> if either operand is a QNAN.</li>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]4059 <li><tt>true</tt>: always yields <tt>true</tt>, regardless of operands.</li>
4060</ol>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]4061
4062<h5>Example:</h5>
4063<pre> &lt;result&gt; = fcmp oeq float 4.0, 5.0 <i>; yields: result=false</i>
Dan Gohmanf72fb672008-09-09 01:02:47 +0000[diff] [blame]4064 &lt;result&gt; = fcmp one float 4.0, 5.0 <i>; yields: result=true</i>
4065 &lt;result&gt; = fcmp olt float 4.0, 5.0 <i>; yields: result=true</i>
4066 &lt;result&gt; = fcmp ueq double 1.0, 2.0 <i>; yields: result=false</i>
Reid Spencerf3a70a62006-11-18 21:50:54 +0000[diff] [blame]4067</pre>
4068</div>
4069
Reid Spencer2fd21e62006-11-08 01:18:52 +0000[diff] [blame]4070<!-- _______________________________________________________________________ -->
Nate Begemanac80ade2008-05-12 19:01:56 +0000[diff] [blame]4071<div class="doc_subsubsection">
4072 <a name="i_vicmp">'<tt>vicmp</tt>' Instruction</a>
4073</div>
4074<div class="doc_text">
4075<h5>Syntax:</h5>
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]4076<pre> &lt;result&gt; = vicmp &lt;cond&gt; &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt; <i>; yields {ty}:result</i>
Nate Begemanac80ade2008-05-12 19:01:56 +0000[diff] [blame]4077</pre>
4078<h5>Overview:</h5>
4079<p>The '<tt>vicmp</tt>' instruction returns an integer vector value based on
4080element-wise comparison of its two integer vector operands.</p>
4081<h5>Arguments:</h5>
4082<p>The '<tt>vicmp</tt>' instruction takes three operands. The first operand is
4083the condition code indicating the kind of comparison to perform. It is not
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]4084a value, just a keyword. The possible condition code are:</p>
Nate Begemanac80ade2008-05-12 19:01:56 +0000[diff] [blame]4085<ol>
4086 <li><tt>eq</tt>: equal</li>
4087 <li><tt>ne</tt>: not equal </li>
4088 <li><tt>ugt</tt>: unsigned greater than</li>
4089 <li><tt>uge</tt>: unsigned greater or equal</li>
4090 <li><tt>ult</tt>: unsigned less than</li>
4091 <li><tt>ule</tt>: unsigned less or equal</li>
4092 <li><tt>sgt</tt>: signed greater than</li>
4093 <li><tt>sge</tt>: signed greater or equal</li>
4094 <li><tt>slt</tt>: signed less than</li>
4095 <li><tt>sle</tt>: signed less or equal</li>
4096</ol>
Dan Gohmanf72fb672008-09-09 01:02:47 +0000[diff] [blame]4097<p>The remaining two arguments must be <a href="#t_vector">vector</a> or
Nate Begemanac80ade2008-05-12 19:01:56 +0000[diff] [blame]4098<a href="#t_integer">integer</a> typed. They must also be identical types.</p>
4099<h5>Semantics:</h5>
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]4100<p>The '<tt>vicmp</tt>' instruction compares <tt>op1</tt> and <tt>op2</tt>
Nate Begemanac80ade2008-05-12 19:01:56 +0000[diff] [blame]4101according to the condition code given as <tt>cond</tt>. The comparison yields a
4102<a href="#t_vector">vector</a> of <a href="#t_integer">integer</a> result, of
4103identical type as the values being compared. The most significant bit in each
4104element is 1 if the element-wise comparison evaluates to true, and is 0
4105otherwise. All other bits of the result are undefined. The condition codes
4106are evaluated identically to the <a href="#i_icmp">'<tt>icmp</tt>'
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]4107instruction</a>.</p>
Nate Begemanac80ade2008-05-12 19:01:56 +0000[diff] [blame]4108
4109<h5>Example:</h5>
4110<pre>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]4111 &lt;result&gt; = vicmp eq &lt;2 x i32&gt; &lt; i32 4, i32 0&gt;, &lt; i32 5, i32 0&gt; <i>; yields: result=&lt;2 x i32&gt; &lt; i32 0, i32 -1 &gt;</i>
4112 &lt;result&gt; = vicmp ult &lt;2 x i8 &gt; &lt; i8 1, i8 2&gt;, &lt; i8 2, i8 2 &gt; <i>; yields: result=&lt;2 x i8&gt; &lt; i8 -1, i8 0 &gt;</i>
Nate Begemanac80ade2008-05-12 19:01:56 +0000[diff] [blame]4113</pre>
4114</div>
4115
4116<!-- _______________________________________________________________________ -->
4117<div class="doc_subsubsection">
4118 <a name="i_vfcmp">'<tt>vfcmp</tt>' Instruction</a>
4119</div>
4120<div class="doc_text">
4121<h5>Syntax:</h5>
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]4122<pre> &lt;result&gt; = vfcmp &lt;cond&gt; &lt;ty&gt; &lt;op1&gt;, &lt;op2&gt;</pre>
Nate Begemanac80ade2008-05-12 19:01:56 +0000[diff] [blame]4123<h5>Overview:</h5>
4124<p>The '<tt>vfcmp</tt>' instruction returns an integer vector value based on
4125element-wise comparison of its two floating point vector operands. The output
4126elements have the same width as the input elements.</p>
4127<h5>Arguments:</h5>
4128<p>The '<tt>vfcmp</tt>' instruction takes three operands. The first operand is
4129the condition code indicating the kind of comparison to perform. It is not
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]4130a value, just a keyword. The possible condition code are:</p>
Nate Begemanac80ade2008-05-12 19:01:56 +0000[diff] [blame]4131<ol>
4132 <li><tt>false</tt>: no comparison, always returns false</li>
4133 <li><tt>oeq</tt>: ordered and equal</li>
4134 <li><tt>ogt</tt>: ordered and greater than </li>
4135 <li><tt>oge</tt>: ordered and greater than or equal</li>
4136 <li><tt>olt</tt>: ordered and less than </li>
4137 <li><tt>ole</tt>: ordered and less than or equal</li>
4138 <li><tt>one</tt>: ordered and not equal</li>
4139 <li><tt>ord</tt>: ordered (no nans)</li>
4140 <li><tt>ueq</tt>: unordered or equal</li>
4141 <li><tt>ugt</tt>: unordered or greater than </li>
4142 <li><tt>uge</tt>: unordered or greater than or equal</li>
4143 <li><tt>ult</tt>: unordered or less than </li>
4144 <li><tt>ule</tt>: unordered or less than or equal</li>
4145 <li><tt>une</tt>: unordered or not equal</li>
4146 <li><tt>uno</tt>: unordered (either nans)</li>
4147 <li><tt>true</tt>: no comparison, always returns true</li>
4148</ol>
4149<p>The remaining two arguments must be <a href="#t_vector">vector</a> of
4150<a href="#t_floating">floating point</a> typed. They must also be identical
4151types.</p>
4152<h5>Semantics:</h5>
Gabor Greiffb224a22008-08-07 21:46:00 +0000[diff] [blame]4153<p>The '<tt>vfcmp</tt>' instruction compares <tt>op1</tt> and <tt>op2</tt>
Nate Begemanac80ade2008-05-12 19:01:56 +0000[diff] [blame]4154according to the condition code given as <tt>cond</tt>. The comparison yields a
4155<a href="#t_vector">vector</a> of <a href="#t_integer">integer</a> result, with
4156an identical number of elements as the values being compared, and each element
4157having identical with to the width of the floating point elements. The most
4158significant bit in each element is 1 if the element-wise comparison evaluates to
4159true, and is 0 otherwise. All other bits of the result are undefined. The
4160condition codes are evaluated identically to the
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]4161<a href="#i_fcmp">'<tt>fcmp</tt>' instruction</a>.</p>
Nate Begemanac80ade2008-05-12 19:01:56 +0000[diff] [blame]4162
4163<h5>Example:</h5>
4164<pre>
Chris Lattner50ad45c2008-10-13 16:55:18 +0000[diff] [blame]4165 <i>; yields: result=&lt;2 x i32&gt; &lt; i32 0, i32 -1 &gt;</i>
4166 &lt;result&gt; = vfcmp oeq &lt;2 x float&gt; &lt; float 4, float 0 &gt;, &lt; float 5, float 0 &gt;
4167
4168 <i>; yields: result=&lt;2 x i64&gt; &lt; i64 -1, i64 0 &gt;</i>
4169 &lt;result&gt; = vfcmp ult &lt;2 x double&gt; &lt; double 1, double 2 &gt;, &lt; double 2, double 2&gt;
Nate Begemanac80ade2008-05-12 19:01:56 +0000[diff] [blame]4170</pre>
4171</div>
4172
4173<!-- _______________________________________________________________________ -->
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]4174<div class="doc_subsubsection">
4175 <a name="i_phi">'<tt>phi</tt>' Instruction</a>
4176</div>
4177
Reid Spencer2fd21e62006-11-08 01:18:52 +0000[diff] [blame]4178<div class="doc_text">
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]4179
Reid Spencer2fd21e62006-11-08 01:18:52 +0000[diff] [blame]4180<h5>Syntax:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]4181
Reid Spencer2fd21e62006-11-08 01:18:52 +0000[diff] [blame]4182<pre> &lt;result&gt; = phi &lt;ty&gt; [ &lt;val0&gt;, &lt;label0&gt;], ...<br></pre>
4183<h5>Overview:</h5>
4184<p>The '<tt>phi</tt>' instruction is used to implement the &#966; node in
4185the SSA graph representing the function.</p>
4186<h5>Arguments:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]4187
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]4188<p>The type of the incoming values is specified with the first type
Reid Spencer2fd21e62006-11-08 01:18:52 +0000[diff] [blame]4189field. After this, the '<tt>phi</tt>' instruction takes a list of pairs
4190as arguments, with one pair for each predecessor basic block of the
4191current block. Only values of <a href="#t_firstclass">first class</a>
4192type may be used as the value arguments to the PHI node. Only labels
4193may be used as the label arguments.</p>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]4194
Reid Spencer2fd21e62006-11-08 01:18:52 +0000[diff] [blame]4195<p>There must be no non-phi instructions between the start of a basic
4196block and the PHI instructions: i.e. PHI instructions must be first in
4197a basic block.</p>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]4198
Reid Spencer2fd21e62006-11-08 01:18:52 +0000[diff] [blame]4199<h5>Semantics:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]4200
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]4201<p>At runtime, the '<tt>phi</tt>' instruction logically takes on the value
4202specified by the pair corresponding to the predecessor basic block that executed
4203just prior to the current block.</p>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]4204
Reid Spencer2fd21e62006-11-08 01:18:52 +0000[diff] [blame]4205<h5>Example:</h5>
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]4206<pre>
4207Loop: ; Infinite loop that counts from 0 on up...
4208 %indvar = phi i32 [ 0, %LoopHeader ], [ %nextindvar, %Loop ]
4209 %nextindvar = add i32 %indvar, 1
4210 br label %Loop
4211</pre>
Reid Spencer2fd21e62006-11-08 01:18:52 +0000[diff] [blame]4212</div>
4213
Chris Lattnercc37aae2004-03-12 05:50:16 +0000[diff] [blame]4214<!-- _______________________________________________________________________ -->
4215<div class="doc_subsubsection">
4216 <a name="i_select">'<tt>select</tt>' Instruction</a>
4217</div>
4218
4219<div class="doc_text">
4220
4221<h5>Syntax:</h5>
4222
4223<pre>
Dan Gohmanf72fb672008-09-09 01:02:47 +0000[diff] [blame]4224 &lt;result&gt; = select <i>selty</i> &lt;cond&gt;, &lt;ty&gt; &lt;val1&gt;, &lt;ty&gt; &lt;val2&gt; <i>; yields ty</i>
4225
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]4226 <i>selty</i> is either i1 or {&lt;N x i1&gt;}
Chris Lattnercc37aae2004-03-12 05:50:16 +0000[diff] [blame]4227</pre>
4228
4229<h5>Overview:</h5>
4230
4231<p>
4232The '<tt>select</tt>' instruction is used to choose one value based on a
4233condition, without branching.
4234</p>
4235
4236
4237<h5>Arguments:</h5>
4238
4239<p>
Dan Gohmanf72fb672008-09-09 01:02:47 +0000[diff] [blame]4240The '<tt>select</tt>' instruction requires an 'i1' value or
4241a vector of 'i1' values indicating the
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]4242condition, and two values of the same <a href="#t_firstclass">first class</a>
Dan Gohmanf72fb672008-09-09 01:02:47 +0000[diff] [blame]4243type. If the val1/val2 are vectors and
4244the condition is a scalar, then entire vectors are selected, not
Chris Lattner5568e942008-05-20 20:48:21 +0000[diff] [blame]4245individual elements.
Chris Lattnercc37aae2004-03-12 05:50:16 +0000[diff] [blame]4246</p>
4247
4248<h5>Semantics:</h5>
4249
4250<p>
Dan Gohmanf72fb672008-09-09 01:02:47 +0000[diff] [blame]4251If the condition is an i1 and it evaluates to 1, the instruction returns the first
John Criswellfc6b8952005-05-16 16:17:45 +0000[diff] [blame]4252value argument; otherwise, it returns the second value argument.
Chris Lattnercc37aae2004-03-12 05:50:16 +0000[diff] [blame]4253</p>
Dan Gohmanf72fb672008-09-09 01:02:47 +0000[diff] [blame]4254<p>
4255If the condition is a vector of i1, then the value arguments must
4256be vectors of the same size, and the selection is done element
4257by element.
4258</p>
Chris Lattnercc37aae2004-03-12 05:50:16 +0000[diff] [blame]4259
4260<h5>Example:</h5>
4261
4262<pre>
Reid Spencerc78f3372007-01-12 03:35:51 +0000[diff] [blame]4263 %X = select i1 true, i8 17, i8 42 <i>; yields i8:17</i>
Chris Lattnercc37aae2004-03-12 05:50:16 +0000[diff] [blame]4264</pre>
4265</div>
4266
Robert Bocchino05ccd702006-01-15 20:48:27 +0000[diff] [blame]4267
4268<!-- _______________________________________________________________________ -->
4269<div class="doc_subsubsection">
Chris Lattner2bff5242005-05-06 05:47:36 +0000[diff] [blame]4270 <a name="i_call">'<tt>call</tt>' Instruction</a>
4271</div>
4272
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]4273<div class="doc_text">
Chris Lattner2bff5242005-05-06 05:47:36 +0000[diff] [blame]4274
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]4275<h5>Syntax:</h5>
Chris Lattner2bff5242005-05-06 05:47:36 +0000[diff] [blame]4276<pre>
Devang Patel307e8ab2008-10-07 17:48:33 +0000[diff] [blame]4277 &lt;result&gt; = [tail] call [<a href="#callingconv">cconv</a>] [<a href="#paramattrs">ret attrs</a>] &lt;ty&gt; [&lt;fnty&gt;*] &lt;fnptrval&gt;(&lt;function args&gt;) [<a href="#fnattrs">fn attrs</a>]
Chris Lattner2bff5242005-05-06 05:47:36 +0000[diff] [blame]4278</pre>
4279
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]4280<h5>Overview:</h5>
Chris Lattner2bff5242005-05-06 05:47:36 +0000[diff] [blame]4281
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]4282<p>The '<tt>call</tt>' instruction represents a simple function call.</p>
Chris Lattner2bff5242005-05-06 05:47:36 +0000[diff] [blame]4283
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]4284<h5>Arguments:</h5>
Chris Lattner2bff5242005-05-06 05:47:36 +0000[diff] [blame]4285
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]4286<p>This instruction requires several arguments:</p>
Chris Lattner2bff5242005-05-06 05:47:36 +0000[diff] [blame]4287
Chris Lattner6536cfe2002-05-06 22:08:29 +0000[diff] [blame]4288<ol>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]4289 <li>
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]4290 <p>The optional "tail" marker indicates whether the callee function accesses
4291 any allocas or varargs in the caller. If the "tail" marker is present, the
Chris Lattner2bff5242005-05-06 05:47:36 +0000[diff] [blame]4292 function call is eligible for tail call optimization. Note that calls may
4293 be marked "tail" even if they do not occur before a <a
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]4294 href="#i_ret"><tt>ret</tt></a> instruction.</p>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]4295 </li>
4296 <li>
Duncan Sands8036ca42007-03-30 12:22:09 +0000[diff] [blame]4297 <p>The optional "cconv" marker indicates which <a href="#callingconv">calling
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]4298 convention</a> the call should use. If none is specified, the call defaults
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]4299 to using C calling conventions.</p>
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]4300 </li>
Devang Patelf642f472008-10-06 18:50:38 +0000[diff] [blame]4301
4302 <li>
4303 <p>The optional <a href="#paramattrs">Parameter Attributes</a> list for
4304 return values. Only '<tt>zeroext</tt>', '<tt>signext</tt>',
4305 and '<tt>inreg</tt>' attributes are valid here.</p>
4306 </li>
4307
Chris Lattnerbad10ee2005-05-06 22:57:40 +0000[diff] [blame]4308 <li>
Nick Lewyckydb7e3c92007-09-08 13:57:50 +0000[diff] [blame]4309 <p>'<tt>ty</tt>': the type of the call instruction itself which is also
4310 the type of the return value. Functions that return no value are marked
4311 <tt><a href="#t_void">void</a></tt>.</p>
4312 </li>
4313 <li>
4314 <p>'<tt>fnty</tt>': shall be the signature of the pointer to function
4315 value being invoked. The argument types must match the types implied by
4316 this signature. This type can be omitted if the function is not varargs
4317 and if the function type does not return a pointer to a function.</p>
Chris Lattner2bff5242005-05-06 05:47:36 +0000[diff] [blame]4318 </li>
4319 <li>
4320 <p>'<tt>fnptrval</tt>': An LLVM value containing a pointer to a function to
4321 be invoked. In most cases, this is a direct function invocation, but
4322 indirect <tt>call</tt>s are just as possible, calling an arbitrary pointer
John Criswellfc6b8952005-05-16 16:17:45 +0000[diff] [blame]4323 to function value.</p>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]4324 </li>
4325 <li>
4326 <p>'<tt>function args</tt>': argument list whose types match the
Reid Spencera7e302a2005-05-01 22:22:57 +0000[diff] [blame]4327 function signature argument types. All arguments must be of
4328 <a href="#t_firstclass">first class</a> type. If the function signature
4329 indicates the function accepts a variable number of arguments, the extra
4330 arguments can be specified.</p>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]4331 </li>
Devang Patelf642f472008-10-06 18:50:38 +0000[diff] [blame]4332 <li>
Devang Patel307e8ab2008-10-07 17:48:33 +0000[diff] [blame]4333 <p>The optional <a href="#fnattrs">function attributes</a> list. Only
Devang Patelf642f472008-10-06 18:50:38 +0000[diff] [blame]4334 '<tt>noreturn</tt>', '<tt>nounwind</tt>', '<tt>readonly</tt>' and
4335 '<tt>readnone</tt>' attributes are valid here.</p>
4336 </li>
Chris Lattner6536cfe2002-05-06 22:08:29 +0000[diff] [blame]4337</ol>
Chris Lattner2bff5242005-05-06 05:47:36 +0000[diff] [blame]4338
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]4339<h5>Semantics:</h5>
Chris Lattner2bff5242005-05-06 05:47:36 +0000[diff] [blame]4340
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]4341<p>The '<tt>call</tt>' instruction is used to cause control flow to
4342transfer to a specified function, with its incoming arguments bound to
4343the specified values. Upon a '<tt><a href="#i_ret">ret</a></tt>'
4344instruction in the called function, control flow continues with the
4345instruction after the function call, and the return value of the
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]4346function is bound to the result argument.</p>
Chris Lattner2bff5242005-05-06 05:47:36 +0000[diff] [blame]4347
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]4348<h5>Example:</h5>
Chris Lattner2bff5242005-05-06 05:47:36 +0000[diff] [blame]4349
4350<pre>
Nick Lewyckydb7e3c92007-09-08 13:57:50 +0000[diff] [blame]4351 %retval = call i32 @test(i32 %argc)
Chris Lattner772fccf2008-03-21 17:24:17 +0000[diff] [blame]4352 call i32 (i8 *, ...)* @printf(i8 * %msg, i32 12, i8 42) <i>; yields i32</i>
4353 %X = tail call i32 @foo() <i>; yields i32</i>
4354 %Y = tail call <a href="#callingconv">fastcc</a> i32 @foo() <i>; yields i32</i>
4355 call void %foo(i8 97 signext)
Devang Patelc3fc6df2008-03-10 20:49:15 +0000[diff] [blame]4356
4357 %struct.A = type { i32, i8 }
Devang Patelf642f472008-10-06 18:50:38 +0000[diff] [blame]4358 %r = call %struct.A @foo() <i>; yields { 32, i8 }</i>
Dan Gohmanb1e6b962008-10-04 19:00:07 +0000[diff] [blame]4359 %gr = extractvalue %struct.A %r, 0 <i>; yields i32</i>
4360 %gr1 = extractvalue %struct.A %r, 1 <i>; yields i8</i>
Chris Lattner85a350f2008-10-08 06:26:11 +0000[diff] [blame]4361 %Z = call void @foo() noreturn <i>; indicates that %foo never returns normally</i>
Matthijs Kooijmancb73d192008-10-07 10:03:45 +0000[diff] [blame]4362 %ZZ = call zeroext i32 @bar() <i>; Return value is %zero extended</i>
Chris Lattner2bff5242005-05-06 05:47:36 +0000[diff] [blame]4363</pre>
4364
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]4365</div>
Chris Lattnere19d7a72004-09-27 21:51:25 +0000[diff] [blame]4366
Chris Lattnerd9ad5b32003-05-08 04:57:36 +0000[diff] [blame]4367<!-- _______________________________________________________________________ -->
Chris Lattnere19d7a72004-09-27 21:51:25 +0000[diff] [blame]4368<div class="doc_subsubsection">
Chris Lattnerfb6977d2006-01-13 23:26:01 +0000[diff] [blame]4369 <a name="i_va_arg">'<tt>va_arg</tt>' Instruction</a>
Chris Lattnere19d7a72004-09-27 21:51:25 +0000[diff] [blame]4370</div>
4371
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]4372<div class="doc_text">
Chris Lattnere19d7a72004-09-27 21:51:25 +0000[diff] [blame]4373
Chris Lattner8d1a81d2003-10-18 05:51:36 +0000[diff] [blame]4374<h5>Syntax:</h5>
Chris Lattnere19d7a72004-09-27 21:51:25 +0000[diff] [blame]4375
4376<pre>
Andrew Lenharth8bf607a2005-06-18 18:28:17 +0000[diff] [blame]4377 &lt;resultval&gt; = va_arg &lt;va_list*&gt; &lt;arglist&gt;, &lt;argty&gt;
Chris Lattnere19d7a72004-09-27 21:51:25 +0000[diff] [blame]4378</pre>
4379
Chris Lattner8d1a81d2003-10-18 05:51:36 +0000[diff] [blame]4380<h5>Overview:</h5>
Chris Lattnere19d7a72004-09-27 21:51:25 +0000[diff] [blame]4381
Andrew Lenharth8bf607a2005-06-18 18:28:17 +0000[diff] [blame]4382<p>The '<tt>va_arg</tt>' instruction is used to access arguments passed through
Chris Lattnere19d7a72004-09-27 21:51:25 +0000[diff] [blame]4383the "variable argument" area of a function call. It is used to implement the
4384<tt>va_arg</tt> macro in C.</p>
4385
Chris Lattner8d1a81d2003-10-18 05:51:36 +0000[diff] [blame]4386<h5>Arguments:</h5>
Chris Lattnere19d7a72004-09-27 21:51:25 +0000[diff] [blame]4387
Andrew Lenharth8bf607a2005-06-18 18:28:17 +0000[diff] [blame]4388<p>This instruction takes a <tt>va_list*</tt> value and the type of
4389the argument. It returns a value of the specified argument type and
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]4390increments the <tt>va_list</tt> to point to the next argument. The
Andrew Lenharth8bf607a2005-06-18 18:28:17 +0000[diff] [blame]4391actual type of <tt>va_list</tt> is target specific.</p>
Chris Lattnere19d7a72004-09-27 21:51:25 +0000[diff] [blame]4392
Chris Lattner8d1a81d2003-10-18 05:51:36 +0000[diff] [blame]4393<h5>Semantics:</h5>
Chris Lattnere19d7a72004-09-27 21:51:25 +0000[diff] [blame]4394
Andrew Lenharth8bf607a2005-06-18 18:28:17 +0000[diff] [blame]4395<p>The '<tt>va_arg</tt>' instruction loads an argument of the specified
4396type from the specified <tt>va_list</tt> and causes the
4397<tt>va_list</tt> to point to the next argument. For more information,
4398see the variable argument handling <a href="#int_varargs">Intrinsic
4399Functions</a>.</p>
Chris Lattnere19d7a72004-09-27 21:51:25 +0000[diff] [blame]4400
4401<p>It is legal for this instruction to be called in a function which does not
4402take a variable number of arguments, for example, the <tt>vfprintf</tt>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]4403function.</p>
Chris Lattnere19d7a72004-09-27 21:51:25 +0000[diff] [blame]4404
Andrew Lenharth8bf607a2005-06-18 18:28:17 +0000[diff] [blame]4405<p><tt>va_arg</tt> is an LLVM instruction instead of an <a
John Criswellfc6b8952005-05-16 16:17:45 +0000[diff] [blame]4406href="#intrinsics">intrinsic function</a> because it takes a type as an
Chris Lattnere19d7a72004-09-27 21:51:25 +0000[diff] [blame]4407argument.</p>
4408
Chris Lattner8d1a81d2003-10-18 05:51:36 +0000[diff] [blame]4409<h5>Example:</h5>
Chris Lattnere19d7a72004-09-27 21:51:25 +0000[diff] [blame]4410
4411<p>See the <a href="#int_varargs">variable argument processing</a> section.</p>
4412
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]4413</div>
Chris Lattner8ff75902004-01-06 05:31:32 +0000[diff] [blame]4414
Chris Lattnerd9ad5b32003-05-08 04:57:36 +0000[diff] [blame]4415<!-- *********************************************************************** -->
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]4416<div class="doc_section"> <a name="intrinsics">Intrinsic Functions</a> </div>
4417<!-- *********************************************************************** -->
Chris Lattner8ff75902004-01-06 05:31:32 +0000[diff] [blame]4418
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]4419<div class="doc_text">
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]4420
4421<p>LLVM supports the notion of an "intrinsic function". These functions have
Reid Spencer409e28f2007-04-01 08:04:23 +0000[diff] [blame]4422well known names and semantics and are required to follow certain restrictions.
4423Overall, these intrinsics represent an extension mechanism for the LLVM
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]4424language that does not require changing all of the transformations in LLVM when
Gabor Greif04367bf2007-07-06 22:07:22 +0000[diff] [blame]4425adding to the language (or the bitcode reader/writer, the parser, etc...).</p>
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]4426
John Criswellfc6b8952005-05-16 16:17:45 +0000[diff] [blame]4427<p>Intrinsic function names must all start with an "<tt>llvm.</tt>" prefix. This
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]4428prefix is reserved in LLVM for intrinsic names; thus, function names may not
4429begin with this prefix. Intrinsic functions must always be external functions:
4430you cannot define the body of intrinsic functions. Intrinsic functions may
4431only be used in call or invoke instructions: it is illegal to take the address
4432of an intrinsic function. Additionally, because intrinsic functions are part
4433of the LLVM language, it is required if any are added that they be documented
4434here.</p>
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]4435
Chandler Carruth69940402007-08-04 01:51:18 +0000[diff] [blame]4436<p>Some intrinsic functions can be overloaded, i.e., the intrinsic represents
4437a family of functions that perform the same operation but on different data
4438types. Because LLVM can represent over 8 million different integer types,
4439overloading is used commonly to allow an intrinsic function to operate on any
4440integer type. One or more of the argument types or the result type can be
4441overloaded to accept any integer type. Argument types may also be defined as
4442exactly matching a previous argument's type or the result type. This allows an
4443intrinsic function which accepts multiple arguments, but needs all of them to
4444be of the same type, to only be overloaded with respect to a single argument or
4445the result.</p>
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]4446
Chandler Carruth69940402007-08-04 01:51:18 +0000[diff] [blame]4447<p>Overloaded intrinsics will have the names of its overloaded argument types
4448encoded into its function name, each preceded by a period. Only those types
4449which are overloaded result in a name suffix. Arguments whose type is matched
4450against another type do not. For example, the <tt>llvm.ctpop</tt> function can
4451take an integer of any width and returns an integer of exactly the same integer
4452width. This leads to a family of functions such as
4453<tt>i8 @llvm.ctpop.i8(i8 %val)</tt> and <tt>i29 @llvm.ctpop.i29(i29 %val)</tt>.
4454Only one type, the return type, is overloaded, and only one type suffix is
4455required. Because the argument's type is matched against the return type, it
4456does not require its own name suffix.</p>
Reid Spencer409e28f2007-04-01 08:04:23 +0000[diff] [blame]4457
4458<p>To learn how to add an intrinsic function, please see the
4459<a href="ExtendingLLVM.html">Extending LLVM Guide</a>.
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]4460</p>
4461
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]4462</div>
Chris Lattner8ff75902004-01-06 05:31:32 +0000[diff] [blame]4463
Chris Lattnerd9ad5b32003-05-08 04:57:36 +0000[diff] [blame]4464<!-- ======================================================================= -->
Chris Lattner8ff75902004-01-06 05:31:32 +0000[diff] [blame]4465<div class="doc_subsection">
4466 <a name="int_varargs">Variable Argument Handling Intrinsics</a>
4467</div>
4468
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]4469<div class="doc_text">
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4470
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]4471<p>Variable argument support is defined in LLVM with the <a
Chris Lattnerfb6977d2006-01-13 23:26:01 +0000[diff] [blame]4472 href="#i_va_arg"><tt>va_arg</tt></a> instruction and these three
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]4473intrinsic functions. These functions are related to the similarly
4474named macros defined in the <tt>&lt;stdarg.h&gt;</tt> header file.</p>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4475
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]4476<p>All of these functions operate on arguments that use a
4477target-specific value type "<tt>va_list</tt>". The LLVM assembly
4478language reference manual does not define what this type is, so all
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]4479transformations should be prepared to handle these functions regardless of
4480the type used.</p>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4481
Chris Lattner374ab302006-05-15 17:26:46 +0000[diff] [blame]4482<p>This example shows how the <a href="#i_va_arg"><tt>va_arg</tt></a>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]4483instruction and the variable argument handling intrinsic functions are
4484used.</p>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4485
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]4486<div class="doc_code">
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]4487<pre>
Anton Korobeynikov5d522f32007-03-21 23:58:04 +0000[diff] [blame]4488define i32 @test(i32 %X, ...) {
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]4489 ; Initialize variable argument processing
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]4490 %ap = alloca i8*
Chris Lattnerb75137d2007-01-08 07:55:15 +0000[diff] [blame]4491 %ap2 = bitcast i8** %ap to i8*
Anton Korobeynikov5d522f32007-03-21 23:58:04 +0000[diff] [blame]4492 call void @llvm.va_start(i8* %ap2)
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]4493
4494 ; Read a single integer argument
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]4495 %tmp = va_arg i8** %ap, i32
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]4496
4497 ; Demonstrate usage of llvm.va_copy and llvm.va_end
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]4498 %aq = alloca i8*
Chris Lattnerb75137d2007-01-08 07:55:15 +0000[diff] [blame]4499 %aq2 = bitcast i8** %aq to i8*
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]4500 call void @llvm.va_copy(i8* %aq2, i8* %ap2)
Anton Korobeynikov5d522f32007-03-21 23:58:04 +0000[diff] [blame]4501 call void @llvm.va_end(i8* %aq2)
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]4502
4503 ; Stop processing of arguments.
Anton Korobeynikov5d522f32007-03-21 23:58:04 +0000[diff] [blame]4504 call void @llvm.va_end(i8* %ap2)
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]4505 ret i32 %tmp
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]4506}
Anton Korobeynikov5d522f32007-03-21 23:58:04 +0000[diff] [blame]4507
4508declare void @llvm.va_start(i8*)
4509declare void @llvm.va_copy(i8*, i8*)
4510declare void @llvm.va_end(i8*)
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]4511</pre>
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]4512</div>
Chris Lattner8ff75902004-01-06 05:31:32 +0000[diff] [blame]4513
Bill Wendling2f7a8b02007-05-29 09:04:49 +0000[diff] [blame]4514</div>
4515
Chris Lattnerd9ad5b32003-05-08 04:57:36 +0000[diff] [blame]4516<!-- _______________________________________________________________________ -->
Chris Lattner8ff75902004-01-06 05:31:32 +0000[diff] [blame]4517<div class="doc_subsubsection">
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]4518 <a name="int_va_start">'<tt>llvm.va_start</tt>' Intrinsic</a>
Chris Lattner8ff75902004-01-06 05:31:32 +0000[diff] [blame]4519</div>
4520
4521
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]4522<div class="doc_text">
Chris Lattnerd9ad5b32003-05-08 04:57:36 +0000[diff] [blame]4523<h5>Syntax:</h5>
Chris Lattnerb75137d2007-01-08 07:55:15 +0000[diff] [blame]4524<pre> declare void %llvm.va_start(i8* &lt;arglist&gt;)<br></pre>
Chris Lattnerd9ad5b32003-05-08 04:57:36 +0000[diff] [blame]4525<h5>Overview:</h5>
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]4526<p>The '<tt>llvm.va_start</tt>' intrinsic initializes
Andrew Lenharth8bf607a2005-06-18 18:28:17 +0000[diff] [blame]4527<tt>*&lt;arglist&gt;</tt> for subsequent use by <tt><a
4528href="#i_va_arg">va_arg</a></tt>.</p>
4529
4530<h5>Arguments:</h5>
4531
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]4532<p>The argument is a pointer to a <tt>va_list</tt> element to initialize.</p>
Andrew Lenharth8bf607a2005-06-18 18:28:17 +0000[diff] [blame]4533
Chris Lattnerd9ad5b32003-05-08 04:57:36 +0000[diff] [blame]4534<h5>Semantics:</h5>
Andrew Lenharth8bf607a2005-06-18 18:28:17 +0000[diff] [blame]4535
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]4536<p>The '<tt>llvm.va_start</tt>' intrinsic works just like the <tt>va_start</tt>
Andrew Lenharth8bf607a2005-06-18 18:28:17 +0000[diff] [blame]4537macro available in C. In a target-dependent way, it initializes the
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]4538<tt>va_list</tt> element to which the argument points, so that the next call to
Andrew Lenharth8bf607a2005-06-18 18:28:17 +0000[diff] [blame]4539<tt>va_arg</tt> will produce the first variable argument passed to the function.
4540Unlike the C <tt>va_start</tt> macro, this intrinsic does not need to know the
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]4541last argument of the function as the compiler can figure that out.</p>
Andrew Lenharth8bf607a2005-06-18 18:28:17 +0000[diff] [blame]4542
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]4543</div>
Chris Lattner8ff75902004-01-06 05:31:32 +0000[diff] [blame]4544
Chris Lattnerd9ad5b32003-05-08 04:57:36 +0000[diff] [blame]4545<!-- _______________________________________________________________________ -->
Chris Lattner8ff75902004-01-06 05:31:32 +0000[diff] [blame]4546<div class="doc_subsubsection">
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]4547 <a name="int_va_end">'<tt>llvm.va_end</tt>' Intrinsic</a>
Chris Lattner8ff75902004-01-06 05:31:32 +0000[diff] [blame]4548</div>
4549
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]4550<div class="doc_text">
Chris Lattnerd9ad5b32003-05-08 04:57:36 +0000[diff] [blame]4551<h5>Syntax:</h5>
Anton Korobeynikovec43a062007-03-22 00:02:17 +0000[diff] [blame]4552<pre> declare void @llvm.va_end(i8* &lt;arglist&gt;)<br></pre>
Chris Lattnerd9ad5b32003-05-08 04:57:36 +0000[diff] [blame]4553<h5>Overview:</h5>
Chris Lattnerb75137d2007-01-08 07:55:15 +0000[diff] [blame]4554
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]4555<p>The '<tt>llvm.va_end</tt>' intrinsic destroys <tt>*&lt;arglist&gt;</tt>,
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]4556which has been initialized previously with <tt><a href="#int_va_start">llvm.va_start</a></tt>
Chris Lattner261efe92003-11-25 01:02:51 +0000[diff] [blame]4557or <tt><a href="#i_va_copy">llvm.va_copy</a></tt>.</p>
Chris Lattnerb75137d2007-01-08 07:55:15 +0000[diff] [blame]4558
Chris Lattnerd9ad5b32003-05-08 04:57:36 +0000[diff] [blame]4559<h5>Arguments:</h5>
Chris Lattnerb75137d2007-01-08 07:55:15 +0000[diff] [blame]4560
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]4561<p>The argument is a pointer to a <tt>va_list</tt> to destroy.</p>
Chris Lattnerb75137d2007-01-08 07:55:15 +0000[diff] [blame]4562
Chris Lattnerd9ad5b32003-05-08 04:57:36 +0000[diff] [blame]4563<h5>Semantics:</h5>
Chris Lattnerb75137d2007-01-08 07:55:15 +0000[diff] [blame]4564
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]4565<p>The '<tt>llvm.va_end</tt>' intrinsic works just like the <tt>va_end</tt>
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]4566macro available in C. In a target-dependent way, it destroys the
4567<tt>va_list</tt> element to which the argument points. Calls to <a
4568href="#int_va_start"><tt>llvm.va_start</tt></a> and <a href="#int_va_copy">
4569<tt>llvm.va_copy</tt></a> must be matched exactly with calls to
4570<tt>llvm.va_end</tt>.</p>
Chris Lattnerb75137d2007-01-08 07:55:15 +0000[diff] [blame]4571
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]4572</div>
Chris Lattner8ff75902004-01-06 05:31:32 +0000[diff] [blame]4573
Chris Lattnerd9ad5b32003-05-08 04:57:36 +0000[diff] [blame]4574<!-- _______________________________________________________________________ -->
Chris Lattner8ff75902004-01-06 05:31:32 +0000[diff] [blame]4575<div class="doc_subsubsection">
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]4576 <a name="int_va_copy">'<tt>llvm.va_copy</tt>' Intrinsic</a>
Chris Lattner8ff75902004-01-06 05:31:32 +0000[diff] [blame]4577</div>
4578
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]4579<div class="doc_text">
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4580
Chris Lattnerd9ad5b32003-05-08 04:57:36 +0000[diff] [blame]4581<h5>Syntax:</h5>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4582
4583<pre>
Anton Korobeynikovec43a062007-03-22 00:02:17 +0000[diff] [blame]4584 declare void @llvm.va_copy(i8* &lt;destarglist&gt;, i8* &lt;srcarglist&gt;)
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4585</pre>
4586
Chris Lattnerd9ad5b32003-05-08 04:57:36 +0000[diff] [blame]4587<h5>Overview:</h5>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4588
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]4589<p>The '<tt>llvm.va_copy</tt>' intrinsic copies the current argument position
4590from the source argument list to the destination argument list.</p>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4591
Chris Lattnerd9ad5b32003-05-08 04:57:36 +0000[diff] [blame]4592<h5>Arguments:</h5>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4593
Andrew Lenharth8bf607a2005-06-18 18:28:17 +0000[diff] [blame]4594<p>The first argument is a pointer to a <tt>va_list</tt> element to initialize.
Andrew Lenharthd0a4c622005-06-22 20:38:11 +0000[diff] [blame]4595The second argument is a pointer to a <tt>va_list</tt> element to copy from.</p>
Andrew Lenharth8bf607a2005-06-18 18:28:17 +0000[diff] [blame]4596
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4597
Chris Lattnerd9ad5b32003-05-08 04:57:36 +0000[diff] [blame]4598<h5>Semantics:</h5>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4599
Jeff Cohenb627eab2007-04-29 01:07:00 +0000[diff] [blame]4600<p>The '<tt>llvm.va_copy</tt>' intrinsic works just like the <tt>va_copy</tt>
4601macro available in C. In a target-dependent way, it copies the source
4602<tt>va_list</tt> element into the destination <tt>va_list</tt> element. This
4603intrinsic is necessary because the <tt><a href="#int_va_start">
4604llvm.va_start</a></tt> intrinsic may be arbitrarily complex and require, for
4605example, memory allocation.</p>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4606
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]4607</div>
Chris Lattner8ff75902004-01-06 05:31:32 +0000[diff] [blame]4608
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]4609<!-- ======================================================================= -->
4610<div class="doc_subsection">
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4611 <a name="int_gc">Accurate Garbage Collection Intrinsics</a>
4612</div>
4613
4614<div class="doc_text">
4615
4616<p>
4617LLVM support for <a href="GarbageCollection.html">Accurate Garbage
Chris Lattnerd3eda892008-08-05 18:29:16 +0000[diff] [blame]4618Collection</a> (GC) requires the implementation and generation of these
4619intrinsics.
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]4620These intrinsics allow identification of <a href="#int_gcroot">GC roots on the
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4621stack</a>, as well as garbage collector implementations that require <a
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]4622href="#int_gcread">read</a> and <a href="#int_gcwrite">write</a> barriers.
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4623Front-ends for type-safe garbage collected languages should generate these
4624intrinsics to make use of the LLVM garbage collectors. For more details, see <a
4625href="GarbageCollection.html">Accurate Garbage Collection with LLVM</a>.
4626</p>
Christopher Lamb303dae92007-12-17 01:00:21 +0000[diff] [blame]4627
4628<p>The garbage collection intrinsics only operate on objects in the generic
4629 address space (address space zero).</p>
4630
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4631</div>
4632
4633<!-- _______________________________________________________________________ -->
4634<div class="doc_subsubsection">
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]4635 <a name="int_gcroot">'<tt>llvm.gcroot</tt>' Intrinsic</a>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4636</div>
4637
4638<div class="doc_text">
4639
4640<h5>Syntax:</h5>
4641
4642<pre>
Chris Lattner1df4f752007-09-21 17:30:40 +0000[diff] [blame]4643 declare void @llvm.gcroot(i8** %ptrloc, i8* %metadata)
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4644</pre>
4645
4646<h5>Overview:</h5>
4647
John Criswell9e2485c2004-12-10 15:51:16 +0000[diff] [blame]4648<p>The '<tt>llvm.gcroot</tt>' intrinsic declares the existence of a GC root to
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4649the code generator, and allows some metadata to be associated with it.</p>
4650
4651<h5>Arguments:</h5>
4652
4653<p>The first argument specifies the address of a stack object that contains the
4654root pointer. The second pointer (which must be either a constant or a global
4655value address) contains the meta-data to be associated with the root.</p>
4656
4657<h5>Semantics:</h5>
4658
Chris Lattner05d67092008-04-24 05:59:56 +0000[diff] [blame]4659<p>At runtime, a call to this intrinsic stores a null pointer into the "ptrloc"
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4660location. At compile-time, the code generator generates information to allow
Gordon Henriksene1433f22007-12-25 02:31:26 +0000[diff] [blame]4661the runtime to find the pointer at GC safe points. The '<tt>llvm.gcroot</tt>'
4662intrinsic may only be used in a function which <a href="#gc">specifies a GC
4663algorithm</a>.</p>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4664
4665</div>
4666
4667
4668<!-- _______________________________________________________________________ -->
4669<div class="doc_subsubsection">
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]4670 <a name="int_gcread">'<tt>llvm.gcread</tt>' Intrinsic</a>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4671</div>
4672
4673<div class="doc_text">
4674
4675<h5>Syntax:</h5>
4676
4677<pre>
Chris Lattner1df4f752007-09-21 17:30:40 +0000[diff] [blame]4678 declare i8* @llvm.gcread(i8* %ObjPtr, i8** %Ptr)
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4679</pre>
4680
4681<h5>Overview:</h5>
4682
4683<p>The '<tt>llvm.gcread</tt>' intrinsic identifies reads of references from heap
4684locations, allowing garbage collector implementations that require read
4685barriers.</p>
4686
4687<h5>Arguments:</h5>
4688
Chris Lattner80626e92006-03-14 20:02:51 +0000[diff] [blame]4689<p>The second argument is the address to read from, which should be an address
4690allocated from the garbage collector. The first object is a pointer to the
4691start of the referenced object, if needed by the language runtime (otherwise
4692null).</p>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4693
4694<h5>Semantics:</h5>
4695
4696<p>The '<tt>llvm.gcread</tt>' intrinsic has the same semantics as a load
4697instruction, but may be replaced with substantially more complex code by the
Gordon Henriksene1433f22007-12-25 02:31:26 +0000[diff] [blame]4698garbage collector runtime, as needed. The '<tt>llvm.gcread</tt>' intrinsic
4699may only be used in a function which <a href="#gc">specifies a GC
4700algorithm</a>.</p>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4701
4702</div>
4703
4704
4705<!-- _______________________________________________________________________ -->
4706<div class="doc_subsubsection">
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]4707 <a name="int_gcwrite">'<tt>llvm.gcwrite</tt>' Intrinsic</a>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4708</div>
4709
4710<div class="doc_text">
4711
4712<h5>Syntax:</h5>
4713
4714<pre>
Chris Lattner1df4f752007-09-21 17:30:40 +0000[diff] [blame]4715 declare void @llvm.gcwrite(i8* %P1, i8* %Obj, i8** %P2)
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4716</pre>
4717
4718<h5>Overview:</h5>
4719
4720<p>The '<tt>llvm.gcwrite</tt>' intrinsic identifies writes of references to heap
4721locations, allowing garbage collector implementations that require write
4722barriers (such as generational or reference counting collectors).</p>
4723
4724<h5>Arguments:</h5>
4725
Chris Lattner80626e92006-03-14 20:02:51 +0000[diff] [blame]4726<p>The first argument is the reference to store, the second is the start of the
4727object to store it to, and the third is the address of the field of Obj to
4728store to. If the runtime does not require a pointer to the object, Obj may be
4729null.</p>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4730
4731<h5>Semantics:</h5>
4732
4733<p>The '<tt>llvm.gcwrite</tt>' intrinsic has the same semantics as a store
4734instruction, but may be replaced with substantially more complex code by the
Gordon Henriksene1433f22007-12-25 02:31:26 +0000[diff] [blame]4735garbage collector runtime, as needed. The '<tt>llvm.gcwrite</tt>' intrinsic
4736may only be used in a function which <a href="#gc">specifies a GC
4737algorithm</a>.</p>
Chris Lattnerd7923912004-05-23 21:06:01 +0000[diff] [blame]4738
4739</div>
4740
4741
4742
4743<!-- ======================================================================= -->
4744<div class="doc_subsection">
Chris Lattner10610642004-02-14 04:08:35 +0000[diff] [blame]4745 <a name="int_codegen">Code Generator Intrinsics</a>
4746</div>
4747
4748<div class="doc_text">
4749<p>
4750These intrinsics are provided by LLVM to expose special features that may only
4751be implemented with code generator support.
4752</p>
4753
4754</div>
4755
4756<!-- _______________________________________________________________________ -->
4757<div class="doc_subsubsection">
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]4758 <a name="int_returnaddress">'<tt>llvm.returnaddress</tt>' Intrinsic</a>
Chris Lattner10610642004-02-14 04:08:35 +0000[diff] [blame]4759</div>
4760
4761<div class="doc_text">
4762
4763<h5>Syntax:</h5>
4764<pre>
Anton Korobeynikovec43a062007-03-22 00:02:17 +0000[diff] [blame]4765 declare i8 *@llvm.returnaddress(i32 &lt;level&gt;)
Chris Lattner10610642004-02-14 04:08:35 +0000[diff] [blame]4766</pre>
4767
4768<h5>Overview:</h5>
4769
4770<p>
Chris Lattner32b5d712006-10-15 20:05:59 +0000[diff] [blame]4771The '<tt>llvm.returnaddress</tt>' intrinsic attempts to compute a
4772target-specific value indicating the return address of the current function
4773or one of its callers.
Chris Lattner10610642004-02-14 04:08:35 +0000[diff] [blame]4774</p>
4775
4776<h5>Arguments:</h5>
4777
4778<p>
4779The argument to this intrinsic indicates which function to return the address
4780for. Zero indicates the calling function, one indicates its caller, etc. The
4781argument is <b>required</b> to be a constant integer value.
4782</p>
4783
4784<h5>Semantics:</h5>
4785
4786<p>
4787The '<tt>llvm.returnaddress</tt>' intrinsic either returns a pointer indicating
4788the return address of the specified call frame, or zero if it cannot be
4789identified. The value returned by this intrinsic is likely to be incorrect or 0
4790for arguments other than zero, so it should only be used for debugging purposes.
4791</p>
4792
4793<p>
4794Note that calling this intrinsic does not prevent function inlining or other
Chris Lattnerb40bb382005-03-07 20:30:51 +0000[diff] [blame]4795aggressive transformations, so the value returned may not be that of the obvious
Chris Lattner10610642004-02-14 04:08:35 +0000[diff] [blame]4796source-language caller.
4797</p>
4798</div>
4799
4800
4801<!-- _______________________________________________________________________ -->
4802<div class="doc_subsubsection">
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]4803 <a name="int_frameaddress">'<tt>llvm.frameaddress</tt>' Intrinsic</a>
Chris Lattner10610642004-02-14 04:08:35 +0000[diff] [blame]4804</div>
4805
4806<div class="doc_text">
4807
4808<h5>Syntax:</h5>
4809<pre>
Chris Lattner1df4f752007-09-21 17:30:40 +0000[diff] [blame]4810 declare i8 *@llvm.frameaddress(i32 &lt;level&gt;)
Chris Lattner10610642004-02-14 04:08:35 +0000[diff] [blame]4811</pre>
4812
4813<h5>Overview:</h5>
4814
4815<p>
Chris Lattner32b5d712006-10-15 20:05:59 +0000[diff] [blame]4816The '<tt>llvm.frameaddress</tt>' intrinsic attempts to return the
4817target-specific frame pointer value for the specified stack frame.
Chris Lattner10610642004-02-14 04:08:35 +0000[diff] [blame]4818</p>
4819
4820<h5>Arguments:</h5>
4821
4822<p>
4823The argument to this intrinsic indicates which function to return the frame
4824pointer for. Zero indicates the calling function, one indicates its caller,
4825etc. The argument is <b>required</b> to be a constant integer value.
4826</p>
4827
4828<h5>Semantics:</h5>
4829
4830<p>
4831The '<tt>llvm.frameaddress</tt>' intrinsic either returns a pointer indicating
4832the frame address of the specified call frame, or zero if it cannot be
4833identified. The value returned by this intrinsic is likely to be incorrect or 0
4834for arguments other than zero, so it should only be used for debugging purposes.
4835</p>
4836
4837<p>
4838Note that calling this intrinsic does not prevent function inlining or other
Chris Lattnerb40bb382005-03-07 20:30:51 +0000[diff] [blame]4839aggressive transformations, so the value returned may not be that of the obvious
Chris Lattner10610642004-02-14 04:08:35 +0000[diff] [blame]4840source-language caller.
4841</p>
4842</div>
4843
Chris Lattner9a9d7ac2005-02-28 19:24:19 +0000[diff] [blame]4844<!-- _______________________________________________________________________ -->
4845<div class="doc_subsubsection">
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]4846 <a name="int_stacksave">'<tt>llvm.stacksave</tt>' Intrinsic</a>
Chris Lattner57e1f392006-01-13 02:03:13 +0000[diff] [blame]4847</div>
4848
4849<div class="doc_text">
4850
4851<h5>Syntax:</h5>
4852<pre>
Chris Lattner1df4f752007-09-21 17:30:40 +0000[diff] [blame]4853 declare i8 *@llvm.stacksave()
Chris Lattner57e1f392006-01-13 02:03:13 +0000[diff] [blame]4854</pre>
4855
4856<h5>Overview:</h5>
4857
4858<p>
4859The '<tt>llvm.stacksave</tt>' intrinsic is used to remember the current state of
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]4860the function stack, for use with <a href="#int_stackrestore">
Chris Lattner57e1f392006-01-13 02:03:13 +0000[diff] [blame]4861<tt>llvm.stackrestore</tt></a>. This is useful for implementing language
4862features like scoped automatic variable sized arrays in C99.
4863</p>
4864
4865<h5>Semantics:</h5>
4866
4867<p>
4868This intrinsic returns a opaque pointer value that can be passed to <a
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]4869href="#int_stackrestore"><tt>llvm.stackrestore</tt></a>. When an
Chris Lattner57e1f392006-01-13 02:03:13 +0000[diff] [blame]4870<tt>llvm.stackrestore</tt> intrinsic is executed with a value saved from
4871<tt>llvm.stacksave</tt>, it effectively restores the state of the stack to the
4872state it was in when the <tt>llvm.stacksave</tt> intrinsic executed. In
4873practice, this pops any <a href="#i_alloca">alloca</a> blocks from the stack
4874that were allocated after the <tt>llvm.stacksave</tt> was executed.
4875</p>
4876
4877</div>
4878
4879<!-- _______________________________________________________________________ -->
4880<div class="doc_subsubsection">
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]4881 <a name="int_stackrestore">'<tt>llvm.stackrestore</tt>' Intrinsic</a>
Chris Lattner57e1f392006-01-13 02:03:13 +0000[diff] [blame]4882</div>
4883
4884<div class="doc_text">
4885
4886<h5>Syntax:</h5>
4887<pre>
Anton Korobeynikovec43a062007-03-22 00:02:17 +0000[diff] [blame]4888 declare void @llvm.stackrestore(i8 * %ptr)
Chris Lattner57e1f392006-01-13 02:03:13 +0000[diff] [blame]4889</pre>
4890
4891<h5>Overview:</h5>
4892
4893<p>
4894The '<tt>llvm.stackrestore</tt>' intrinsic is used to restore the state of
4895the function stack to the state it was in when the corresponding <a
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]4896href="#int_stacksave"><tt>llvm.stacksave</tt></a> intrinsic executed. This is
Chris Lattner57e1f392006-01-13 02:03:13 +0000[diff] [blame]4897useful for implementing language features like scoped automatic variable sized
4898arrays in C99.
4899</p>
4900
4901<h5>Semantics:</h5>
4902
4903<p>
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]4904See the description for <a href="#int_stacksave"><tt>llvm.stacksave</tt></a>.
Chris Lattner57e1f392006-01-13 02:03:13 +0000[diff] [blame]4905</p>
4906
4907</div>
4908
4909
4910<!-- _______________________________________________________________________ -->
4911<div class="doc_subsubsection">
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]4912 <a name="int_prefetch">'<tt>llvm.prefetch</tt>' Intrinsic</a>
Chris Lattner9a9d7ac2005-02-28 19:24:19 +0000[diff] [blame]4913</div>
4914
4915<div class="doc_text">
4916
4917<h5>Syntax:</h5>
4918<pre>
Chris Lattner1df4f752007-09-21 17:30:40 +0000[diff] [blame]4919 declare void @llvm.prefetch(i8* &lt;address&gt;, i32 &lt;rw&gt;, i32 &lt;locality&gt;)
Chris Lattner9a9d7ac2005-02-28 19:24:19 +0000[diff] [blame]4920</pre>
4921
4922<h5>Overview:</h5>
4923
4924
4925<p>
4926The '<tt>llvm.prefetch</tt>' intrinsic is a hint to the code generator to insert
John Criswellfc6b8952005-05-16 16:17:45 +0000[diff] [blame]4927a prefetch instruction if supported; otherwise, it is a noop. Prefetches have
4928no
4929effect on the behavior of the program but can change its performance
Chris Lattner2a615362005-02-28 19:47:14 +0000[diff] [blame]4930characteristics.
Chris Lattner9a9d7ac2005-02-28 19:24:19 +0000[diff] [blame]4931</p>
4932
4933<h5>Arguments:</h5>
4934
4935<p>
4936<tt>address</tt> is the address to be prefetched, <tt>rw</tt> is the specifier
4937determining if the fetch should be for a read (0) or write (1), and
4938<tt>locality</tt> is a temporal locality specifier ranging from (0) - no
Chris Lattneraeffb4a2005-03-07 20:31:38 +0000[diff] [blame]4939locality, to (3) - extremely local keep in cache. The <tt>rw</tt> and
Chris Lattner9a9d7ac2005-02-28 19:24:19 +0000[diff] [blame]4940<tt>locality</tt> arguments must be constant integers.
4941</p>
4942
4943<h5>Semantics:</h5>
4944
4945<p>
4946This intrinsic does not modify the behavior of the program. In particular,
4947prefetches cannot trap and do not produce a value. On targets that support this
4948intrinsic, the prefetch can provide hints to the processor cache for better
4949performance.
4950</p>
4951
4952</div>
4953
Andrew Lenharth7f4ec3b2005-03-28 20:05:49 +0000[diff] [blame]4954<!-- _______________________________________________________________________ -->
4955<div class="doc_subsubsection">
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]4956 <a name="int_pcmarker">'<tt>llvm.pcmarker</tt>' Intrinsic</a>
Andrew Lenharth7f4ec3b2005-03-28 20:05:49 +0000[diff] [blame]4957</div>
4958
4959<div class="doc_text">
4960
4961<h5>Syntax:</h5>
4962<pre>
Chris Lattner1df4f752007-09-21 17:30:40 +0000[diff] [blame]4963 declare void @llvm.pcmarker(i32 &lt;id&gt;)
Andrew Lenharth7f4ec3b2005-03-28 20:05:49 +0000[diff] [blame]4964</pre>
4965
4966<h5>Overview:</h5>
4967
4968
4969<p>
John Criswellfc6b8952005-05-16 16:17:45 +0000[diff] [blame]4970The '<tt>llvm.pcmarker</tt>' intrinsic is a method to export a Program Counter
Chris Lattnerd3eda892008-08-05 18:29:16 +0000[diff] [blame]4971(PC) in a region of
4972code to simulators and other tools. The method is target specific, but it is
4973expected that the marker will use exported symbols to transmit the PC of the
4974marker.
4975The marker makes no guarantees that it will remain with any specific instruction
4976after optimizations. It is possible that the presence of a marker will inhibit
Chris Lattnerb3e7afd2006-03-24 07:16:10 +0000[diff] [blame]4977optimizations. The intended use is to be inserted after optimizations to allow
John Criswellfc6b8952005-05-16 16:17:45 +0000[diff] [blame]4978correlations of simulation runs.
Andrew Lenharth7f4ec3b2005-03-28 20:05:49 +0000[diff] [blame]4979</p>
4980
4981<h5>Arguments:</h5>
4982
4983<p>
4984<tt>id</tt> is a numerical id identifying the marker.
4985</p>
4986
4987<h5>Semantics:</h5>
4988
4989<p>
4990This intrinsic does not modify the behavior of the program. Backends that do not
4991support this intrinisic may ignore it.
4992</p>
4993
4994</div>
4995
Andrew Lenharth51b8d542005-11-11 16:47:30 +0000[diff] [blame]4996<!-- _______________________________________________________________________ -->
4997<div class="doc_subsubsection">
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]4998 <a name="int_readcyclecounter">'<tt>llvm.readcyclecounter</tt>' Intrinsic</a>
Andrew Lenharth51b8d542005-11-11 16:47:30 +0000[diff] [blame]4999</div>
5000
5001<div class="doc_text">
5002
5003<h5>Syntax:</h5>
5004<pre>
Anton Korobeynikovec43a062007-03-22 00:02:17 +0000[diff] [blame]5005 declare i64 @llvm.readcyclecounter( )
Andrew Lenharth51b8d542005-11-11 16:47:30 +0000[diff] [blame]5006</pre>
5007
5008<h5>Overview:</h5>
5009
5010
5011<p>
5012The '<tt>llvm.readcyclecounter</tt>' intrinsic provides access to the cycle
5013counter register (or similar low latency, high accuracy clocks) on those targets
5014that support it. On X86, it should map to RDTSC. On Alpha, it should map to RPCC.
5015As the backing counters overflow quickly (on the order of 9 seconds on alpha), this
5016should only be used for small timings.
5017</p>
5018
5019<h5>Semantics:</h5>
5020
5021<p>
5022When directly supported, reading the cycle counter should not modify any memory.
5023Implementations are allowed to either return a application specific value or a
5024system wide value. On backends without support, this is lowered to a constant 0.
5025</p>
5026
5027</div>
5028
Chris Lattner10610642004-02-14 04:08:35 +0000[diff] [blame]5029<!-- ======================================================================= -->
5030<div class="doc_subsection">
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]5031 <a name="int_libc">Standard C Library Intrinsics</a>
5032</div>
5033
5034<div class="doc_text">
5035<p>
Chris Lattner10610642004-02-14 04:08:35 +0000[diff] [blame]5036LLVM provides intrinsics for a few important standard C library functions.
5037These intrinsics allow source-language front-ends to pass information about the
5038alignment of the pointer arguments to the code generator, providing opportunity
5039for more efficient code generation.
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]5040</p>
5041
5042</div>
5043
5044<!-- _______________________________________________________________________ -->
5045<div class="doc_subsubsection">
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]5046 <a name="int_memcpy">'<tt>llvm.memcpy</tt>' Intrinsic</a>
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]5047</div>
5048
5049<div class="doc_text">
5050
5051<h5>Syntax:</h5>
5052<pre>
Anton Korobeynikovec43a062007-03-22 00:02:17 +0000[diff] [blame]5053 declare void @llvm.memcpy.i32(i8 * &lt;dest&gt;, i8 * &lt;src&gt;,
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]5054 i32 &lt;len&gt;, i32 &lt;align&gt;)
Anton Korobeynikovec43a062007-03-22 00:02:17 +0000[diff] [blame]5055 declare void @llvm.memcpy.i64(i8 * &lt;dest&gt;, i8 * &lt;src&gt;,
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]5056 i64 &lt;len&gt;, i32 &lt;align&gt;)
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]5057</pre>
5058
5059<h5>Overview:</h5>
5060
5061<p>
Chris Lattner5b310c32006-03-03 00:07:20 +0000[diff] [blame]5062The '<tt>llvm.memcpy.*</tt>' intrinsics copy a block of memory from the source
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]5063location to the destination location.
5064</p>
5065
5066<p>
Chris Lattner5b310c32006-03-03 00:07:20 +0000[diff] [blame]5067Note that, unlike the standard libc function, the <tt>llvm.memcpy.*</tt>
5068intrinsics do not return a value, and takes an extra alignment argument.
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]5069</p>
5070
5071<h5>Arguments:</h5>
5072
5073<p>
5074The first argument is a pointer to the destination, the second is a pointer to
Chris Lattner5b310c32006-03-03 00:07:20 +0000[diff] [blame]5075the source. The third argument is an integer argument
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]5076specifying the number of bytes to copy, and the fourth argument is the alignment
5077of the source and destination locations.
5078</p>
5079
Chris Lattner3301ced2004-02-12 21:18:15 +0000[diff] [blame]5080<p>
5081If the call to this intrinisic has an alignment value that is not 0 or 1, then
Chris Lattnerf0afc2c2006-03-04 00:02:10 +0000[diff] [blame]5082the caller guarantees that both the source and destination pointers are aligned
5083to that boundary.
Chris Lattner3301ced2004-02-12 21:18:15 +0000[diff] [blame]5084</p>
5085
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]5086<h5>Semantics:</h5>
5087
5088<p>
Chris Lattner5b310c32006-03-03 00:07:20 +0000[diff] [blame]5089The '<tt>llvm.memcpy.*</tt>' intrinsics copy a block of memory from the source
Chris Lattner33aec9e2004-02-12 17:01:32 +0000[diff] [blame]5090location to the destination location, which are not allowed to overlap. It
5091copies "len" bytes of memory over. If the argument is known to be aligned to
5092some boundary, this can be specified as the fourth argument, otherwise it should
5093be set to 0 or 1.
5094</p>
5095</div>
5096
5097
Chris Lattner0eb51b42004-02-12 18:10:10 +0000[diff] [blame]5098<!-- _______________________________________________________________________ -->
5099<div class="doc_subsubsection">
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]5100 <a name="int_memmove">'<tt>llvm.memmove</tt>' Intrinsic</a>
Chris Lattner0eb51b42004-02-12 18:10:10 +0000[diff] [blame]5101</div>
5102
5103<div class="doc_text">
5104
5105<h5>Syntax:</h5>
5106<pre>
Anton Korobeynikovec43a062007-03-22 00:02:17 +0000[diff] [blame]5107 declare void @llvm.memmove.i32(i8 * &lt;dest&gt;, i8 * &lt;src&gt;,
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]5108 i32 &lt;len&gt;, i32 &lt;align&gt;)
Anton Korobeynikovec43a062007-03-22 00:02:17 +0000[diff] [blame]5109 declare void @llvm.memmove.i64(i8 * &lt;dest&gt;, i8 * &lt;src&gt;,
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]5110 i64 &lt;len&gt;, i32 &lt;align&gt;)
Chris Lattner0eb51b42004-02-12 18:10:10 +0000[diff] [blame]5111</pre>
5112
5113<h5>Overview:</h5>
5114
5115<p>
Chris Lattner5b310c32006-03-03 00:07:20 +0000[diff] [blame]5116The '<tt>llvm.memmove.*</tt>' intrinsics move a block of memory from the source
5117location to the destination location. It is similar to the
Chris Lattner4b2cbcf2008-01-06 19:51:52 +0000[diff] [blame]5118'<tt>llvm.memcpy</tt>' intrinsic but allows the two memory locations to overlap.
Chris Lattner0eb51b42004-02-12 18:10:10 +0000[diff] [blame]5119</p>
5120
5121<p>
Chris Lattner5b310c32006-03-03 00:07:20 +0000[diff] [blame]5122Note that, unlike the standard libc function, the <tt>llvm.memmove.*</tt>
5123intrinsics do not return a value, and takes an extra alignment argument.
Chris Lattner0eb51b42004-02-12 18:10:10 +0000[diff] [blame]5124</p>
5125
5126<h5>Arguments:</h5>
5127
5128<p>
5129The first argument is a pointer to the destination, the second is a pointer to
Chris Lattner5b310c32006-03-03 00:07:20 +0000[diff] [blame]5130the source. The third argument is an integer argument
Chris Lattner0eb51b42004-02-12 18:10:10 +0000[diff] [blame]5131specifying the number of bytes to copy, and the fourth argument is the alignment
5132of the source and destination locations.
5133</p>
5134
Chris Lattner3301ced2004-02-12 21:18:15 +0000[diff] [blame]5135<p>
5136If the call to this intrinisic has an alignment value that is not 0 or 1, then
Chris Lattnerf0afc2c2006-03-04 00:02:10 +0000[diff] [blame]5137the caller guarantees that the source and destination pointers are aligned to
5138that boundary.
Chris Lattner3301ced2004-02-12 21:18:15 +0000[diff] [blame]5139</p>
5140
Chris Lattner0eb51b42004-02-12 18:10:10 +0000[diff] [blame]5141<h5>Semantics:</h5>
5142
5143<p>
Chris Lattner5b310c32006-03-03 00:07:20 +0000[diff] [blame]5144The '<tt>llvm.memmove.*</tt>' intrinsics copy a block of memory from the source
Chris Lattner0eb51b42004-02-12 18:10:10 +0000[diff] [blame]5145location to the destination location, which may overlap. It
5146copies "len" bytes of memory over. If the argument is known to be aligned to
5147some boundary, this can be specified as the fourth argument, otherwise it should
5148be set to 0 or 1.
5149</p>
5150</div>
5151
Chris Lattner8ff75902004-01-06 05:31:32 +0000[diff] [blame]5152
Chris Lattner10610642004-02-14 04:08:35 +0000[diff] [blame]5153<!-- _______________________________________________________________________ -->
5154<div class="doc_subsubsection">
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]5155 <a name="int_memset">'<tt>llvm.memset.*</tt>' Intrinsics</a>
Chris Lattner10610642004-02-14 04:08:35 +0000[diff] [blame]5156</div>
5157
5158<div class="doc_text">
5159
5160<h5>Syntax:</h5>
5161<pre>
Anton Korobeynikovec43a062007-03-22 00:02:17 +0000[diff] [blame]5162 declare void @llvm.memset.i32(i8 * &lt;dest&gt;, i8 &lt;val&gt;,
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]5163 i32 &lt;len&gt;, i32 &lt;align&gt;)
Anton Korobeynikovec43a062007-03-22 00:02:17 +0000[diff] [blame]5164 declare void @llvm.memset.i64(i8 * &lt;dest&gt;, i8 &lt;val&gt;,
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]5165 i64 &lt;len&gt;, i32 &lt;align&gt;)
Chris Lattner10610642004-02-14 04:08:35 +0000[diff] [blame]5166</pre>
5167
5168<h5>Overview:</h5>
5169
5170<p>
Chris Lattner5b310c32006-03-03 00:07:20 +0000[diff] [blame]5171The '<tt>llvm.memset.*</tt>' intrinsics fill a block of memory with a particular
Chris Lattner10610642004-02-14 04:08:35 +0000[diff] [blame]5172byte value.
5173</p>
5174
5175<p>
5176Note that, unlike the standard libc function, the <tt>llvm.memset</tt> intrinsic
5177does not return a value, and takes an extra alignment argument.
5178</p>
5179
5180<h5>Arguments:</h5>
5181
5182<p>
5183The first argument is a pointer to the destination to fill, the second is the
Chris Lattner5b310c32006-03-03 00:07:20 +0000[diff] [blame]5184byte value to fill it with, the third argument is an integer
Chris Lattner10610642004-02-14 04:08:35 +0000[diff] [blame]5185argument specifying the number of bytes to fill, and the fourth argument is the
5186known alignment of destination location.
5187</p>
5188
5189<p>
5190If the call to this intrinisic has an alignment value that is not 0 or 1, then
Chris Lattnerf0afc2c2006-03-04 00:02:10 +0000[diff] [blame]5191the caller guarantees that the destination pointer is aligned to that boundary.
Chris Lattner10610642004-02-14 04:08:35 +0000[diff] [blame]5192</p>
5193
5194<h5>Semantics:</h5>
5195
5196<p>
Chris Lattner5b310c32006-03-03 00:07:20 +0000[diff] [blame]5197The '<tt>llvm.memset.*</tt>' intrinsics fill "len" bytes of memory starting at
5198the
Chris Lattner10610642004-02-14 04:08:35 +0000[diff] [blame]5199destination location. If the argument is known to be aligned to some boundary,
5200this can be specified as the fourth argument, otherwise it should be set to 0 or
52011.
5202</p>
5203</div>
5204
5205
Chris Lattner32006282004-06-11 02:28:03 +0000[diff] [blame]5206<!-- _______________________________________________________________________ -->
5207<div class="doc_subsubsection">
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]5208 <a name="int_sqrt">'<tt>llvm.sqrt.*</tt>' Intrinsic</a>
Chris Lattnera4d74142005-07-21 01:29:16 +0000[diff] [blame]5209</div>
5210
5211<div class="doc_text">
5212
5213<h5>Syntax:</h5>
Dale Johannesen408f9c12007-10-02 17:47:38 +0000[diff] [blame]5214<p>This is an overloaded intrinsic. You can use <tt>llvm.sqrt</tt> on any
Dan Gohman91c284c2007-10-15 20:30:11 +0000[diff] [blame]5215floating point or vector of floating point type. Not all targets support all
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]5216types however.</p>
Chris Lattnera4d74142005-07-21 01:29:16 +0000[diff] [blame]5217<pre>
Dale Johannesen408f9c12007-10-02 17:47:38 +0000[diff] [blame]5218 declare float @llvm.sqrt.f32(float %Val)
5219 declare double @llvm.sqrt.f64(double %Val)
5220 declare x86_fp80 @llvm.sqrt.f80(x86_fp80 %Val)
5221 declare fp128 @llvm.sqrt.f128(fp128 %Val)
5222 declare ppc_fp128 @llvm.sqrt.ppcf128(ppc_fp128 %Val)
Chris Lattnera4d74142005-07-21 01:29:16 +0000[diff] [blame]5223</pre>
5224
5225<h5>Overview:</h5>
5226
5227<p>
Reid Spencer0b118202006-01-16 21:12:35 +0000[diff] [blame]5228The '<tt>llvm.sqrt</tt>' intrinsics return the sqrt of the specified operand,
Dan Gohman91c284c2007-10-15 20:30:11 +0000[diff] [blame]5229returning the same value as the libm '<tt>sqrt</tt>' functions would. Unlike
Chris Lattnera4d74142005-07-21 01:29:16 +0000[diff] [blame]5230<tt>sqrt</tt> in libm, however, <tt>llvm.sqrt</tt> has undefined behavior for
Chris Lattner103e2d72008-01-29 07:00:44 +0000[diff] [blame]5231negative numbers other than -0.0 (which allows for better optimization, because
5232there is no need to worry about errno being set). <tt>llvm.sqrt(-0.0)</tt> is
5233defined to return -0.0 like IEEE sqrt.
Chris Lattnera4d74142005-07-21 01:29:16 +0000[diff] [blame]5234</p>
5235
5236<h5>Arguments:</h5>
5237
5238<p>
5239The argument and return value are floating point numbers of the same type.
5240</p>
5241
5242<h5>Semantics:</h5>
5243
5244<p>
Dan Gohmand6257fe2007-07-16 14:37:41 +0000[diff] [blame]5245This function returns the sqrt of the specified operand if it is a nonnegative
Chris Lattnera4d74142005-07-21 01:29:16 +0000[diff] [blame]5246floating point number.
5247</p>
5248</div>
5249
Chris Lattnerf4d252d2006-09-08 06:34:02 +0000[diff] [blame]5250<!-- _______________________________________________________________________ -->
5251<div class="doc_subsubsection">
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]5252 <a name="int_powi">'<tt>llvm.powi.*</tt>' Intrinsic</a>
Chris Lattnerf4d252d2006-09-08 06:34:02 +0000[diff] [blame]5253</div>
5254
5255<div class="doc_text">
5256
5257<h5>Syntax:</h5>
Dale Johannesen408f9c12007-10-02 17:47:38 +0000[diff] [blame]5258<p>This is an overloaded intrinsic. You can use <tt>llvm.powi</tt> on any
Dan Gohman91c284c2007-10-15 20:30:11 +0000[diff] [blame]5259floating point or vector of floating point type. Not all targets support all
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]5260types however.</p>
Chris Lattnerf4d252d2006-09-08 06:34:02 +0000[diff] [blame]5261<pre>
Dale Johannesen408f9c12007-10-02 17:47:38 +0000[diff] [blame]5262 declare float @llvm.powi.f32(float %Val, i32 %power)
5263 declare double @llvm.powi.f64(double %Val, i32 %power)
5264 declare x86_fp80 @llvm.powi.f80(x86_fp80 %Val, i32 %power)
5265 declare fp128 @llvm.powi.f128(fp128 %Val, i32 %power)
5266 declare ppc_fp128 @llvm.powi.ppcf128(ppc_fp128 %Val, i32 %power)
Chris Lattnerf4d252d2006-09-08 06:34:02 +0000[diff] [blame]5267</pre>
5268
5269<h5>Overview:</h5>
5270
5271<p>
5272The '<tt>llvm.powi.*</tt>' intrinsics return the first operand raised to the
5273specified (positive or negative) power. The order of evaluation of
Dan Gohman91c284c2007-10-15 20:30:11 +0000[diff] [blame]5274multiplications is not defined. When a vector of floating point type is
5275used, the second argument remains a scalar integer value.
Chris Lattnerf4d252d2006-09-08 06:34:02 +0000[diff] [blame]5276</p>
5277
5278<h5>Arguments:</h5>
5279
5280<p>
5281The second argument is an integer power, and the first is a value to raise to
5282that power.
5283</p>
5284
5285<h5>Semantics:</h5>
5286
5287<p>
5288This function returns the first value raised to the second power with an
5289unspecified sequence of rounding operations.</p>
5290</div>
5291
Dan Gohman91c284c2007-10-15 20:30:11 +0000[diff] [blame]5292<!-- _______________________________________________________________________ -->
5293<div class="doc_subsubsection">
5294 <a name="int_sin">'<tt>llvm.sin.*</tt>' Intrinsic</a>
5295</div>
5296
5297<div class="doc_text">
5298
5299<h5>Syntax:</h5>
5300<p>This is an overloaded intrinsic. You can use <tt>llvm.sin</tt> on any
5301floating point or vector of floating point type. Not all targets support all
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]5302types however.</p>
Dan Gohman91c284c2007-10-15 20:30:11 +0000[diff] [blame]5303<pre>
5304 declare float @llvm.sin.f32(float %Val)
5305 declare double @llvm.sin.f64(double %Val)
5306 declare x86_fp80 @llvm.sin.f80(x86_fp80 %Val)
5307 declare fp128 @llvm.sin.f128(fp128 %Val)
5308 declare ppc_fp128 @llvm.sin.ppcf128(ppc_fp128 %Val)
5309</pre>
5310
5311<h5>Overview:</h5>
5312
5313<p>
5314The '<tt>llvm.sin.*</tt>' intrinsics return the sine of the operand.
5315</p>
5316
5317<h5>Arguments:</h5>
5318
5319<p>
5320The argument and return value are floating point numbers of the same type.
5321</p>
5322
5323<h5>Semantics:</h5>
5324
5325<p>
5326This function returns the sine of the specified operand, returning the
5327same values as the libm <tt>sin</tt> functions would, and handles error
Dan Gohmanba83b7e2007-10-17 18:05:13 +0000[diff] [blame]5328conditions in the same way.</p>
Dan Gohman91c284c2007-10-15 20:30:11 +0000[diff] [blame]5329</div>
5330
5331<!-- _______________________________________________________________________ -->
5332<div class="doc_subsubsection">
5333 <a name="int_cos">'<tt>llvm.cos.*</tt>' Intrinsic</a>
5334</div>
5335
5336<div class="doc_text">
5337
5338<h5>Syntax:</h5>
5339<p>This is an overloaded intrinsic. You can use <tt>llvm.cos</tt> on any
5340floating point or vector of floating point type. Not all targets support all
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]5341types however.</p>
Dan Gohman91c284c2007-10-15 20:30:11 +0000[diff] [blame]5342<pre>
5343 declare float @llvm.cos.f32(float %Val)
5344 declare double @llvm.cos.f64(double %Val)
5345 declare x86_fp80 @llvm.cos.f80(x86_fp80 %Val)
5346 declare fp128 @llvm.cos.f128(fp128 %Val)
5347 declare ppc_fp128 @llvm.cos.ppcf128(ppc_fp128 %Val)
5348</pre>
5349
5350<h5>Overview:</h5>
5351
5352<p>
5353The '<tt>llvm.cos.*</tt>' intrinsics return the cosine of the operand.
5354</p>
5355
5356<h5>Arguments:</h5>
5357
5358<p>
5359The argument and return value are floating point numbers of the same type.
5360</p>
5361
5362<h5>Semantics:</h5>
5363
5364<p>
5365This function returns the cosine of the specified operand, returning the
5366same values as the libm <tt>cos</tt> functions would, and handles error
Dan Gohmanba83b7e2007-10-17 18:05:13 +0000[diff] [blame]5367conditions in the same way.</p>
Dan Gohman91c284c2007-10-15 20:30:11 +0000[diff] [blame]5368</div>
5369
5370<!-- _______________________________________________________________________ -->
5371<div class="doc_subsubsection">
5372 <a name="int_pow">'<tt>llvm.pow.*</tt>' Intrinsic</a>
5373</div>
5374
5375<div class="doc_text">
5376
5377<h5>Syntax:</h5>
5378<p>This is an overloaded intrinsic. You can use <tt>llvm.pow</tt> on any
5379floating point or vector of floating point type. Not all targets support all
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]5380types however.</p>
Dan Gohman91c284c2007-10-15 20:30:11 +0000[diff] [blame]5381<pre>
5382 declare float @llvm.pow.f32(float %Val, float %Power)
5383 declare double @llvm.pow.f64(double %Val, double %Power)
5384 declare x86_fp80 @llvm.pow.f80(x86_fp80 %Val, x86_fp80 %Power)
5385 declare fp128 @llvm.pow.f128(fp128 %Val, fp128 %Power)
5386 declare ppc_fp128 @llvm.pow.ppcf128(ppc_fp128 %Val, ppc_fp128 Power)
5387</pre>
5388
5389<h5>Overview:</h5>
5390
5391<p>
5392The '<tt>llvm.pow.*</tt>' intrinsics return the first operand raised to the
5393specified (positive or negative) power.
5394</p>
5395
5396<h5>Arguments:</h5>
5397
5398<p>
5399The second argument is a floating point power, and the first is a value to
5400raise to that power.
5401</p>
5402
5403<h5>Semantics:</h5>
5404
5405<p>
5406This function returns the first value raised to the second power,
5407returning the
5408same values as the libm <tt>pow</tt> functions would, and handles error
Dan Gohmanba83b7e2007-10-17 18:05:13 +0000[diff] [blame]5409conditions in the same way.</p>
Dan Gohman91c284c2007-10-15 20:30:11 +0000[diff] [blame]5410</div>
5411
Chris Lattnerf4d252d2006-09-08 06:34:02 +0000[diff] [blame]5412
Andrew Lenharthec370fd2005-05-03 18:01:48 +0000[diff] [blame]5413<!-- ======================================================================= -->
5414<div class="doc_subsection">
Nate Begeman7e36c472006-01-13 23:26:38 +0000[diff] [blame]5415 <a name="int_manip">Bit Manipulation Intrinsics</a>
Andrew Lenharthec370fd2005-05-03 18:01:48 +0000[diff] [blame]5416</div>
5417
5418<div class="doc_text">
5419<p>
Nate Begeman7e36c472006-01-13 23:26:38 +0000[diff] [blame]5420LLVM provides intrinsics for a few important bit manipulation operations.
Andrew Lenharthec370fd2005-05-03 18:01:48 +0000[diff] [blame]5421These allow efficient code generation for some algorithms.
5422</p>
5423
5424</div>
5425
5426<!-- _______________________________________________________________________ -->
5427<div class="doc_subsubsection">
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]5428 <a name="int_bswap">'<tt>llvm.bswap.*</tt>' Intrinsics</a>
Nate Begeman7e36c472006-01-13 23:26:38 +0000[diff] [blame]5429</div>
5430
5431<div class="doc_text">
5432
5433<h5>Syntax:</h5>
Reid Spencer409e28f2007-04-01 08:04:23 +0000[diff] [blame]5434<p>This is an overloaded intrinsic function. You can use bswap on any integer
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]5435type that is an even number of bytes (i.e. BitWidth % 16 == 0).</p>
Nate Begeman7e36c472006-01-13 23:26:38 +0000[diff] [blame]5436<pre>
Chandler Carruth69940402007-08-04 01:51:18 +0000[diff] [blame]5437 declare i16 @llvm.bswap.i16(i16 &lt;id&gt;)
5438 declare i32 @llvm.bswap.i32(i32 &lt;id&gt;)
5439 declare i64 @llvm.bswap.i64(i64 &lt;id&gt;)
Nate Begeman7e36c472006-01-13 23:26:38 +0000[diff] [blame]5440</pre>
5441
5442<h5>Overview:</h5>
5443
5444<p>
Reid Spencer338ea092007-04-02 02:25:19 +0000[diff] [blame]5445The '<tt>llvm.bswap</tt>' family of intrinsics is used to byte swap integer
Reid Spencer409e28f2007-04-01 08:04:23 +0000[diff] [blame]5446values with an even number of bytes (positive multiple of 16 bits). These are
5447useful for performing operations on data that is not in the target's native
5448byte order.
Nate Begeman7e36c472006-01-13 23:26:38 +0000[diff] [blame]5449</p>
5450
5451<h5>Semantics:</h5>
5452
5453<p>
Chandler Carruth69940402007-08-04 01:51:18 +0000[diff] [blame]5454The <tt>llvm.bswap.i16</tt> intrinsic returns an i16 value that has the high
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]5455and low byte of the input i16 swapped. Similarly, the <tt>llvm.bswap.i32</tt>
5456intrinsic returns an i32 value that has the four bytes of the input i32
5457swapped, so that if the input bytes are numbered 0, 1, 2, 3 then the returned
Chandler Carruth69940402007-08-04 01:51:18 +0000[diff] [blame]5458i32 will have its bytes in 3, 2, 1, 0 order. The <tt>llvm.bswap.i48</tt>,
5459<tt>llvm.bswap.i64</tt> and other intrinsics extend this concept to
Reid Spencer409e28f2007-04-01 08:04:23 +0000[diff] [blame]5460additional even-byte lengths (6 bytes, 8 bytes and more, respectively).
Nate Begeman7e36c472006-01-13 23:26:38 +0000[diff] [blame]5461</p>
5462
5463</div>
5464
5465<!-- _______________________________________________________________________ -->
5466<div class="doc_subsubsection">
Reid Spencer0b118202006-01-16 21:12:35 +0000[diff] [blame]5467 <a name="int_ctpop">'<tt>llvm.ctpop.*</tt>' Intrinsic</a>
Andrew Lenharthec370fd2005-05-03 18:01:48 +0000[diff] [blame]5468</div>
5469
5470<div class="doc_text">
5471
5472<h5>Syntax:</h5>
Reid Spencer409e28f2007-04-01 08:04:23 +0000[diff] [blame]5473<p>This is an overloaded intrinsic. You can use llvm.ctpop on any integer bit
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]5474width. Not all targets support all bit widths however.</p>
Andrew Lenharthec370fd2005-05-03 18:01:48 +0000[diff] [blame]5475<pre>
Chandler Carruth69940402007-08-04 01:51:18 +0000[diff] [blame]5476 declare i8 @llvm.ctpop.i8 (i8 &lt;src&gt;)
5477 declare i16 @llvm.ctpop.i16(i16 &lt;src&gt;)
Anton Korobeynikovec43a062007-03-22 00:02:17 +0000[diff] [blame]5478 declare i32 @llvm.ctpop.i32(i32 &lt;src&gt;)
Chandler Carruth69940402007-08-04 01:51:18 +0000[diff] [blame]5479 declare i64 @llvm.ctpop.i64(i64 &lt;src&gt;)
5480 declare i256 @llvm.ctpop.i256(i256 &lt;src&gt;)
Andrew Lenharthec370fd2005-05-03 18:01:48 +0000[diff] [blame]5481</pre>
5482
5483<h5>Overview:</h5>
5484
5485<p>
Chris Lattnerec6cb612006-01-16 22:38:59 +0000[diff] [blame]5486The '<tt>llvm.ctpop</tt>' family of intrinsics counts the number of bits set in a
5487value.
Andrew Lenharthec370fd2005-05-03 18:01:48 +0000[diff] [blame]5488</p>
5489
5490<h5>Arguments:</h5>
5491
5492<p>
Chris Lattnercfe6b372005-05-07 01:46:40 +0000[diff] [blame]5493The only argument is the value to be counted. The argument may be of any
Reid Spencera5173382007-01-04 16:43:23 +0000[diff] [blame]5494integer type. The return type must match the argument type.
Andrew Lenharthec370fd2005-05-03 18:01:48 +0000[diff] [blame]5495</p>
5496
5497<h5>Semantics:</h5>
5498
5499<p>
5500The '<tt>llvm.ctpop</tt>' intrinsic counts the 1's in a variable.
5501</p>
5502</div>
5503
5504<!-- _______________________________________________________________________ -->
5505<div class="doc_subsubsection">
Chris Lattner8a886be2006-01-16 22:34:14 +0000[diff] [blame]5506 <a name="int_ctlz">'<tt>llvm.ctlz.*</tt>' Intrinsic</a>
Andrew Lenharthec370fd2005-05-03 18:01:48 +0000[diff] [blame]5507</div>
5508
5509<div class="doc_text">
5510
5511<h5>Syntax:</h5>
Reid Spencer409e28f2007-04-01 08:04:23 +0000[diff] [blame]5512<p>This is an overloaded intrinsic. You can use <tt>llvm.ctlz</tt> on any
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]5513integer bit width. Not all targets support all bit widths however.</p>
Andrew Lenharthec370fd2005-05-03 18:01:48 +0000[diff] [blame]5514<pre>
Chandler Carruth69940402007-08-04 01:51:18 +0000[diff] [blame]5515 declare i8 @llvm.ctlz.i8 (i8 &lt;src&gt;)
5516 declare i16 @llvm.ctlz.i16(i16 &lt;src&gt;)
Anton Korobeynikovec43a062007-03-22 00:02:17 +0000[diff] [blame]5517 declare i32 @llvm.ctlz.i32(i32 &lt;src&gt;)
Chandler Carruth69940402007-08-04 01:51:18 +0000[diff] [blame]5518 declare i64 @llvm.ctlz.i64(i64 &lt;src&gt;)
5519 declare i256 @llvm.ctlz.i256(i256 &lt;src&gt;)
Andrew Lenharthec370fd2005-05-03 18:01:48 +0000[diff] [blame]5520</pre>
5521
5522<h5>Overview:</h5>
5523
5524<p>
Reid Spencer0b118202006-01-16 21:12:35 +0000[diff] [blame]5525The '<tt>llvm.ctlz</tt>' family of intrinsic functions counts the number of
5526leading zeros in a variable.
Andrew Lenharthec370fd2005-05-03 18:01:48 +0000[diff] [blame]5527</p>
5528
5529<h5>Arguments:</h5>
5530
5531<p>
Chris Lattnercfe6b372005-05-07 01:46:40 +0000[diff] [blame]5532The only argument is the value to be counted. The argument may be of any
Reid Spencera5173382007-01-04 16:43:23 +0000[diff] [blame]5533integer type. The return type must match the argument type.
Andrew Lenharthec370fd2005-05-03 18:01:48 +0000[diff] [blame]5534</p>
5535
5536<h5>Semantics:</h5>
5537
5538<p>
Chris Lattnereff29ab2005-05-15 19:39:26 +0000[diff] [blame]5539The '<tt>llvm.ctlz</tt>' intrinsic counts the leading (most significant) zeros
5540in a variable. If the src == 0 then the result is the size in bits of the type
Reid Spencerca86e162006-12-31 07:07:53 +0000[diff] [blame]5541of src. For example, <tt>llvm.ctlz(i32 2) = 30</tt>.
Andrew Lenharthec370fd2005-05-03 18:01:48 +0000[diff] [blame]5542</p>
5543</div>
Chris Lattner32006282004-06-11 02:28:03 +0000[diff] [blame]5544
5545
Chris Lattnereff29ab2005-05-15 19:39:26 +0000[diff] [blame]5546
5547<!-- _______________________________________________________________________ -->
5548<div class="doc_subsubsection">
Chris Lattner8a886be2006-01-16 22:34:14 +0000[diff] [blame]5549 <a name="int_cttz">'<tt>llvm.cttz.*</tt>' Intrinsic</a>
Chris Lattnereff29ab2005-05-15 19:39:26 +0000[diff] [blame]5550</div>
5551
5552<div class="doc_text">
5553
5554<h5>Syntax:</h5>
Reid Spencer409e28f2007-04-01 08:04:23 +0000[diff] [blame]5555<p>This is an overloaded intrinsic. You can use <tt>llvm.cttz</tt> on any
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]5556integer bit width. Not all targets support all bit widths however.</p>
Chris Lattnereff29ab2005-05-15 19:39:26 +0000[diff] [blame]5557<pre>
Chandler Carruth69940402007-08-04 01:51:18 +0000[diff] [blame]5558 declare i8 @llvm.cttz.i8 (i8 &lt;src&gt;)
5559 declare i16 @llvm.cttz.i16(i16 &lt;src&gt;)
Anton Korobeynikovec43a062007-03-22 00:02:17 +0000[diff] [blame]5560 declare i32 @llvm.cttz.i32(i32 &lt;src&gt;)
Chandler Carruth69940402007-08-04 01:51:18 +0000[diff] [blame]5561 declare i64 @llvm.cttz.i64(i64 &lt;src&gt;)
5562 declare i256 @llvm.cttz.i256(i256 &lt;src&gt;)
Chris Lattnereff29ab2005-05-15 19:39:26 +0000[diff] [blame]5563</pre>
5564
5565<h5>Overview:</h5>
5566
5567<p>
Reid Spencer0b118202006-01-16 21:12:35 +0000[diff] [blame]5568The '<tt>llvm.cttz</tt>' family of intrinsic functions counts the number of
5569trailing zeros.
Chris Lattnereff29ab2005-05-15 19:39:26 +0000[diff] [blame]5570</p>
5571
5572<h5>Arguments:</h5>
5573
5574<p>
5575The only argument is the value to be counted. The argument may be of any
Reid Spencera5173382007-01-04 16:43:23 +0000[diff] [blame]5576integer type. The return type must match the argument type.
Chris Lattnereff29ab2005-05-15 19:39:26 +0000[diff] [blame]5577</p>
5578
5579<h5>Semantics:</h5>
5580
5581<p>
5582The '<tt>llvm.cttz</tt>' intrinsic counts the trailing (least significant) zeros
5583in a variable. If the src == 0 then the result is the size in bits of the type
5584of src. For example, <tt>llvm.cttz(2) = 1</tt>.
5585</p>
5586</div>
5587
Reid Spencer497d93e2007-04-01 08:27:01 +0000[diff] [blame]5588<!-- _______________________________________________________________________ -->
5589<div class="doc_subsubsection">
Reid Spencerbeacf662007-04-10 02:51:31 +0000[diff] [blame]5590 <a name="int_part_select">'<tt>llvm.part.select.*</tt>' Intrinsic</a>
Reid Spencera13ba7d2007-04-01 19:00:37 +0000[diff] [blame]5591</div>
5592
5593<div class="doc_text">
5594
5595<h5>Syntax:</h5>
Reid Spencerbeacf662007-04-10 02:51:31 +0000[diff] [blame]5596<p>This is an overloaded intrinsic. You can use <tt>llvm.part.select</tt>
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]5597on any integer bit width.</p>
Reid Spencera13ba7d2007-04-01 19:00:37 +0000[diff] [blame]5598<pre>
Chandler Carruth69940402007-08-04 01:51:18 +0000[diff] [blame]5599 declare i17 @llvm.part.select.i17 (i17 %val, i32 %loBit, i32 %hiBit)
5600 declare i29 @llvm.part.select.i29 (i29 %val, i32 %loBit, i32 %hiBit)
Reid Spencera13ba7d2007-04-01 19:00:37 +0000[diff] [blame]5601</pre>
5602
5603<h5>Overview:</h5>
Reid Spencerbeacf662007-04-10 02:51:31 +0000[diff] [blame]5604<p>The '<tt>llvm.part.select</tt>' family of intrinsic functions selects a
Reid Spencera13ba7d2007-04-01 19:00:37 +0000[diff] [blame]5605range of bits from an integer value and returns them in the same bit width as
5606the original value.</p>
5607
5608<h5>Arguments:</h5>
5609<p>The first argument, <tt>%val</tt> and the result may be integer types of
5610any bit width but they must have the same bit width. The second and third
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]5611arguments must be <tt>i32</tt> type since they specify only a bit index.</p>
Reid Spencera13ba7d2007-04-01 19:00:37 +0000[diff] [blame]5612
5613<h5>Semantics:</h5>
Reid Spencerbeacf662007-04-10 02:51:31 +0000[diff] [blame]5614<p>The operation of the '<tt>llvm.part.select</tt>' intrinsic has two modes
Reid Spencera3e435f2007-04-04 02:42:35 +0000[diff] [blame]5615of operation: forwards and reverse. If <tt>%loBit</tt> is greater than
5616<tt>%hiBits</tt> then the intrinsic operates in reverse mode. Otherwise it
5617operates in forward mode.</p>
5618<p>In forward mode, this intrinsic is the equivalent of shifting <tt>%val</tt>
5619right by <tt>%loBit</tt> bits and then ANDing it with a mask with
Reid Spencera13ba7d2007-04-01 19:00:37 +0000[diff] [blame]5620only the <tt>%hiBit - %loBit</tt> bits set, as follows:</p>
5621<ol>
5622 <li>The <tt>%val</tt> is shifted right (LSHR) by the number of bits specified
5623 by <tt>%loBits</tt>. This normalizes the value to the low order bits.</li>
5624 <li>The <tt>%loBits</tt> value is subtracted from the <tt>%hiBits</tt> value
5625 to determine the number of bits to retain.</li>
5626 <li>A mask of the retained bits is created by shifting a -1 value.</li>
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]5627 <li>The mask is ANDed with <tt>%val</tt> to produce the result.</li>
Reid Spencera13ba7d2007-04-01 19:00:37 +0000[diff] [blame]5628</ol>
Reid Spencerd6a85b52007-05-14 16:14:57 +0000[diff] [blame]5629<p>In reverse mode, a similar computation is made except that the bits are
5630returned in the reverse order. So, for example, if <tt>X</tt> has the value
5631<tt>i16 0x0ACF (101011001111)</tt> and we apply
5632<tt>part.select(i16 X, 8, 3)</tt> to it, we get back the value
5633<tt>i16 0x0026 (000000100110)</tt>.</p>
Reid Spencera13ba7d2007-04-01 19:00:37 +0000[diff] [blame]5634</div>
5635
Reid Spencerf86037f2007-04-11 23:23:49 +0000[diff] [blame]5636<div class="doc_subsubsection">
5637 <a name="int_part_set">'<tt>llvm.part.set.*</tt>' Intrinsic</a>
5638</div>
5639
5640<div class="doc_text">
5641
5642<h5>Syntax:</h5>
5643<p>This is an overloaded intrinsic. You can use <tt>llvm.part.set</tt>
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]5644on any integer bit width.</p>
Reid Spencerf86037f2007-04-11 23:23:49 +0000[diff] [blame]5645<pre>
Chandler Carruth69940402007-08-04 01:51:18 +0000[diff] [blame]5646 declare i17 @llvm.part.set.i17.i9 (i17 %val, i9 %repl, i32 %lo, i32 %hi)
5647 declare i29 @llvm.part.set.i29.i9 (i29 %val, i9 %repl, i32 %lo, i32 %hi)
Reid Spencerf86037f2007-04-11 23:23:49 +0000[diff] [blame]5648</pre>
5649
5650<h5>Overview:</h5>
5651<p>The '<tt>llvm.part.set</tt>' family of intrinsic functions replaces a range
5652of bits in an integer value with another integer value. It returns the integer
5653with the replaced bits.</p>
5654
5655<h5>Arguments:</h5>
5656<p>The first argument, <tt>%val</tt> and the result may be integer types of
5657any bit width but they must have the same bit width. <tt>%val</tt> is the value
5658whose bits will be replaced. The second argument, <tt>%repl</tt> may be an
5659integer of any bit width. The third and fourth arguments must be <tt>i32</tt>
5660type since they specify only a bit index.</p>
5661
5662<h5>Semantics:</h5>
5663<p>The operation of the '<tt>llvm.part.set</tt>' intrinsic has two modes
5664of operation: forwards and reverse. If <tt>%lo</tt> is greater than
5665<tt>%hi</tt> then the intrinsic operates in reverse mode. Otherwise it
5666operates in forward mode.</p>
5667<p>For both modes, the <tt>%repl</tt> value is prepared for use by either
5668truncating it down to the size of the replacement area or zero extending it
5669up to that size.</p>
5670<p>In forward mode, the bits between <tt>%lo</tt> and <tt>%hi</tt> (inclusive)
5671are replaced with corresponding bits from <tt>%repl</tt>. That is the 0th bit
5672in <tt>%repl</tt> replaces the <tt>%lo</tt>th bit in <tt>%val</tt> and etc. up
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]5673to the <tt>%hi</tt>th bit.</p>
Reid Spencerc6749c42007-05-14 16:50:20 +0000[diff] [blame]5674<p>In reverse mode, a similar computation is made except that the bits are
5675reversed. That is, the <tt>0</tt>th bit in <tt>%repl</tt> replaces the
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]5676<tt>%hi</tt> bit in <tt>%val</tt> and etc. down to the <tt>%lo</tt>th bit.</p>
Reid Spencerf86037f2007-04-11 23:23:49 +0000[diff] [blame]5677<h5>Examples:</h5>
5678<pre>
Reid Spencerf0dbf642007-04-12 01:03:03 +0000[diff] [blame]5679 llvm.part.set(0xFFFF, 0, 4, 7) -&gt; 0xFF0F
Reid Spencerc6749c42007-05-14 16:50:20 +0000[diff] [blame]5680 llvm.part.set(0xFFFF, 0, 7, 4) -&gt; 0xFF0F
5681 llvm.part.set(0xFFFF, 1, 7, 4) -&gt; 0xFF8F
5682 llvm.part.set(0xFFFF, F, 8, 3) -&gt; 0xFFE7
Reid Spencerf0dbf642007-04-12 01:03:03 +0000[diff] [blame]5683 llvm.part.set(0xFFFF, 0, 3, 8) -&gt; 0xFE07
Reid Spencerc8910842007-04-11 23:49:50 +0000[diff] [blame]5684</pre>
Reid Spencerf86037f2007-04-11 23:23:49 +0000[diff] [blame]5685</div>
5686
Chris Lattner8ff75902004-01-06 05:31:32 +0000[diff] [blame]5687<!-- ======================================================================= -->
5688<div class="doc_subsection">
5689 <a name="int_debugger">Debugger Intrinsics</a>
5690</div>
5691
5692<div class="doc_text">
5693<p>
5694The LLVM debugger intrinsics (which all start with <tt>llvm.dbg.</tt> prefix),
5695are described in the <a
5696href="SourceLevelDebugging.html#format_common_intrinsics">LLVM Source Level
5697Debugging</a> document.
5698</p>
5699</div>
5700
5701
Jim Laskeydd4ef1b2007-03-14 19:31:19 +0000[diff] [blame]5702<!-- ======================================================================= -->
5703<div class="doc_subsection">
5704 <a name="int_eh">Exception Handling Intrinsics</a>
5705</div>
5706
5707<div class="doc_text">
5708<p> The LLVM exception handling intrinsics (which all start with
5709<tt>llvm.eh.</tt> prefix), are described in the <a
5710href="ExceptionHandling.html#format_common_intrinsics">LLVM Exception
5711Handling</a> document. </p>
5712</div>
5713
Tanya Lattner6d806e92007-06-15 20:50:54 +0000[diff] [blame]5714<!-- ======================================================================= -->
5715<div class="doc_subsection">
Duncan Sandsf7331b32007-09-11 14:10:23 +0000[diff] [blame]5716 <a name="int_trampoline">Trampoline Intrinsic</a>
Duncan Sands36397f52007-07-27 12:58:54 +0000[diff] [blame]5717</div>
5718
5719<div class="doc_text">
5720<p>
Duncan Sandsf7331b32007-09-11 14:10:23 +0000[diff] [blame]5721 This intrinsic makes it possible to excise one parameter, marked with
Duncan Sands36397f52007-07-27 12:58:54 +0000[diff] [blame]5722 the <tt>nest</tt> attribute, from a function. The result is a callable
5723 function pointer lacking the nest parameter - the caller does not need
5724 to provide a value for it. Instead, the value to use is stored in
5725 advance in a "trampoline", a block of memory usually allocated
5726 on the stack, which also contains code to splice the nest value into the
5727 argument list. This is used to implement the GCC nested function address
5728 extension.
5729</p>
5730<p>
5731 For example, if the function is
5732 <tt>i32 f(i8* nest %c, i32 %x, i32 %y)</tt> then the resulting function
Bill Wendling03295ca2007-09-22 09:23:55 +0000[diff] [blame]5733 pointer has signature <tt>i32 (i32, i32)*</tt>. It can be created as follows:</p>
Duncan Sands36397f52007-07-27 12:58:54 +0000[diff] [blame]5734<pre>
Duncan Sandsf7331b32007-09-11 14:10:23 +0000[diff] [blame]5735 %tramp = alloca [10 x i8], align 4 ; size and alignment only correct for X86
5736 %tramp1 = getelementptr [10 x i8]* %tramp, i32 0, i32 0
5737 %p = call i8* @llvm.init.trampoline( i8* %tramp1, i8* bitcast (i32 (i8* nest , i32, i32)* @f to i8*), i8* %nval )
5738 %fp = bitcast i8* %p to i32 (i32, i32)*
Duncan Sands36397f52007-07-27 12:58:54 +0000[diff] [blame]5739</pre>
Bill Wendling03295ca2007-09-22 09:23:55 +0000[diff] [blame]5740 <p>The call <tt>%val = call i32 %fp( i32 %x, i32 %y )</tt> is then equivalent
5741 to <tt>%val = call i32 %f( i8* %nval, i32 %x, i32 %y )</tt>.</p>
Duncan Sands36397f52007-07-27 12:58:54 +0000[diff] [blame]5742</div>
5743
5744<!-- _______________________________________________________________________ -->
5745<div class="doc_subsubsection">
5746 <a name="int_it">'<tt>llvm.init.trampoline</tt>' Intrinsic</a>
5747</div>
5748<div class="doc_text">
5749<h5>Syntax:</h5>
5750<pre>
Duncan Sandsf7331b32007-09-11 14:10:23 +0000[diff] [blame]5751declare i8* @llvm.init.trampoline(i8* &lt;tramp&gt;, i8* &lt;func&gt;, i8* &lt;nval&gt;)
Duncan Sands36397f52007-07-27 12:58:54 +0000[diff] [blame]5752</pre>
5753<h5>Overview:</h5>
5754<p>
Duncan Sandsf7331b32007-09-11 14:10:23 +0000[diff] [blame]5755 This fills the memory pointed to by <tt>tramp</tt> with code
5756 and returns a function pointer suitable for executing it.
Duncan Sands36397f52007-07-27 12:58:54 +0000[diff] [blame]5757</p>
5758<h5>Arguments:</h5>
5759<p>
5760 The <tt>llvm.init.trampoline</tt> intrinsic takes three arguments, all
5761 pointers. The <tt>tramp</tt> argument must point to a sufficiently large
5762 and sufficiently aligned block of memory; this memory is written to by the
Duncan Sandsc00c2ba2007-08-22 23:39:54 +0000[diff] [blame]5763 intrinsic. Note that the size and the alignment are target-specific - LLVM
5764 currently provides no portable way of determining them, so a front-end that
5765 generates this intrinsic needs to have some target-specific knowledge.
5766 The <tt>func</tt> argument must hold a function bitcast to an <tt>i8*</tt>.
Duncan Sands36397f52007-07-27 12:58:54 +0000[diff] [blame]5767</p>
5768<h5>Semantics:</h5>
5769<p>
5770 The block of memory pointed to by <tt>tramp</tt> is filled with target
Duncan Sandsf7331b32007-09-11 14:10:23 +0000[diff] [blame]5771 dependent code, turning it into a function. A pointer to this function is
5772 returned, but needs to be bitcast to an
Duncan Sands36397f52007-07-27 12:58:54 +0000[diff] [blame]5773 <a href="#int_trampoline">appropriate function pointer type</a>
Duncan Sandsf7331b32007-09-11 14:10:23 +0000[diff] [blame]5774 before being called. The new function's signature is the same as that of
5775 <tt>func</tt> with any arguments marked with the <tt>nest</tt> attribute
5776 removed. At most one such <tt>nest</tt> argument is allowed, and it must be
5777 of pointer type. Calling the new function is equivalent to calling
5778 <tt>func</tt> with the same argument list, but with <tt>nval</tt> used for the
5779 missing <tt>nest</tt> argument. If, after calling
5780 <tt>llvm.init.trampoline</tt>, the memory pointed to by <tt>tramp</tt> is
5781 modified, then the effect of any later call to the returned function pointer is
5782 undefined.
Duncan Sands36397f52007-07-27 12:58:54 +0000[diff] [blame]5783</p>
5784</div>
5785
5786<!-- ======================================================================= -->
5787<div class="doc_subsection">
Andrew Lenharth22c5c1b2008-02-16 01:24:58 +0000[diff] [blame]5788 <a name="int_atomics">Atomic Operations and Synchronization Intrinsics</a>
5789</div>
5790
5791<div class="doc_text">
5792<p>
5793 These intrinsic functions expand the "universal IR" of LLVM to represent
5794 hardware constructs for atomic operations and memory synchronization. This
5795 provides an interface to the hardware, not an interface to the programmer. It
Chris Lattnerd3eda892008-08-05 18:29:16 +0000[diff] [blame]5796 is aimed at a low enough level to allow any programming models or APIs
5797 (Application Programming Interfaces) which
Andrew Lenharth22c5c1b2008-02-16 01:24:58 +0000[diff] [blame]5798 need atomic behaviors to map cleanly onto it. It is also modeled primarily on
5799 hardware behavior. Just as hardware provides a "universal IR" for source
5800 languages, it also provides a starting point for developing a "universal"
5801 atomic operation and synchronization IR.
5802</p>
5803<p>
5804 These do <em>not</em> form an API such as high-level threading libraries,
5805 software transaction memory systems, atomic primitives, and intrinsic
5806 functions as found in BSD, GNU libc, atomic_ops, APR, and other system and
5807 application libraries. The hardware interface provided by LLVM should allow
5808 a clean implementation of all of these APIs and parallel programming models.
5809 No one model or paradigm should be selected above others unless the hardware
5810 itself ubiquitously does so.
5811
5812</p>
5813</div>
5814
5815<!-- _______________________________________________________________________ -->
5816<div class="doc_subsubsection">
5817 <a name="int_memory_barrier">'<tt>llvm.memory.barrier</tt>' Intrinsic</a>
5818</div>
5819<div class="doc_text">
5820<h5>Syntax:</h5>
5821<pre>
5822declare void @llvm.memory.barrier( i1 &lt;ll&gt;, i1 &lt;ls&gt;, i1 &lt;sl&gt;, i1 &lt;ss&gt;,
5823i1 &lt;device&gt; )
5824
5825</pre>
5826<h5>Overview:</h5>
5827<p>
5828 The <tt>llvm.memory.barrier</tt> intrinsic guarantees ordering between
5829 specific pairs of memory access types.
5830</p>
5831<h5>Arguments:</h5>
5832<p>
5833 The <tt>llvm.memory.barrier</tt> intrinsic requires five boolean arguments.
5834 The first four arguments enables a specific barrier as listed below. The fith
5835 argument specifies that the barrier applies to io or device or uncached memory.
5836
5837</p>
5838 <ul>
5839 <li><tt>ll</tt>: load-load barrier</li>
5840 <li><tt>ls</tt>: load-store barrier</li>
5841 <li><tt>sl</tt>: store-load barrier</li>
5842 <li><tt>ss</tt>: store-store barrier</li>
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]5843 <li><tt>device</tt>: barrier applies to device and uncached memory also.</li>
Andrew Lenharth22c5c1b2008-02-16 01:24:58 +0000[diff] [blame]5844 </ul>
5845<h5>Semantics:</h5>
5846<p>
5847 This intrinsic causes the system to enforce some ordering constraints upon
5848 the loads and stores of the program. This barrier does not indicate
5849 <em>when</em> any events will occur, it only enforces an <em>order</em> in
5850 which they occur. For any of the specified pairs of load and store operations
5851 (f.ex. load-load, or store-load), all of the first operations preceding the
5852 barrier will complete before any of the second operations succeeding the
5853 barrier begin. Specifically the semantics for each pairing is as follows:
5854</p>
5855 <ul>
5856 <li><tt>ll</tt>: All loads before the barrier must complete before any load
5857 after the barrier begins.</li>
5858
5859 <li><tt>ls</tt>: All loads before the barrier must complete before any
5860 store after the barrier begins.</li>
5861 <li><tt>ss</tt>: All stores before the barrier must complete before any
5862 store after the barrier begins.</li>
5863 <li><tt>sl</tt>: All stores before the barrier must complete before any
5864 load after the barrier begins.</li>
5865 </ul>
5866<p>
5867 These semantics are applied with a logical "and" behavior when more than one
5868 is enabled in a single memory barrier intrinsic.
5869</p>
5870<p>
5871 Backends may implement stronger barriers than those requested when they do not
5872 support as fine grained a barrier as requested. Some architectures do not
5873 need all types of barriers and on such architectures, these become noops.
5874</p>
5875<h5>Example:</h5>
5876<pre>
5877%ptr = malloc i32
5878 store i32 4, %ptr
5879
5880%result1 = load i32* %ptr <i>; yields {i32}:result1 = 4</i>
5881 call void @llvm.memory.barrier( i1 false, i1 true, i1 false, i1 false )
5882 <i>; guarantee the above finishes</i>
5883 store i32 8, %ptr <i>; before this begins</i>
5884</pre>
5885</div>
5886
Andrew Lenharthab0b9492008-02-21 06:45:13 +0000[diff] [blame]5887<!-- _______________________________________________________________________ -->
5888<div class="doc_subsubsection">
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]5889 <a name="int_atomic_cmp_swap">'<tt>llvm.atomic.cmp.swap.*</tt>' Intrinsic</a>
Andrew Lenharthab0b9492008-02-21 06:45:13 +0000[diff] [blame]5890</div>
5891<div class="doc_text">
5892<h5>Syntax:</h5>
5893<p>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]5894 This is an overloaded intrinsic. You can use <tt>llvm.atomic.cmp.swap</tt> on
5895 any integer bit width and for different address spaces. Not all targets
5896 support all bit widths however.</p>
Andrew Lenharthab0b9492008-02-21 06:45:13 +0000[diff] [blame]5897
5898<pre>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]5899declare i8 @llvm.atomic.cmp.swap.i8.p0i8( i8* &lt;ptr&gt;, i8 &lt;cmp&gt;, i8 &lt;val&gt; )
5900declare i16 @llvm.atomic.cmp.swap.i16.p0i16( i16* &lt;ptr&gt;, i16 &lt;cmp&gt;, i16 &lt;val&gt; )
5901declare i32 @llvm.atomic.cmp.swap.i32.p0i32( i32* &lt;ptr&gt;, i32 &lt;cmp&gt;, i32 &lt;val&gt; )
5902declare i64 @llvm.atomic.cmp.swap.i64.p0i64( i64* &lt;ptr&gt;, i64 &lt;cmp&gt;, i64 &lt;val&gt; )
Andrew Lenharthab0b9492008-02-21 06:45:13 +0000[diff] [blame]5903
5904</pre>
5905<h5>Overview:</h5>
5906<p>
5907 This loads a value in memory and compares it to a given value. If they are
5908 equal, it stores a new value into the memory.
5909</p>
5910<h5>Arguments:</h5>
5911<p>
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]5912 The <tt>llvm.atomic.cmp.swap</tt> intrinsic takes three arguments. The result as
Andrew Lenharthab0b9492008-02-21 06:45:13 +0000[diff] [blame]5913 well as both <tt>cmp</tt> and <tt>val</tt> must be integer values with the
5914 same bit width. The <tt>ptr</tt> argument must be a pointer to a value of
5915 this integer type. While any bit width integer may be used, targets may only
5916 lower representations they support in hardware.
5917
5918</p>
5919<h5>Semantics:</h5>
5920<p>
5921 This entire intrinsic must be executed atomically. It first loads the value
5922 in memory pointed to by <tt>ptr</tt> and compares it with the value
5923 <tt>cmp</tt>. If they are equal, <tt>val</tt> is stored into the memory. The
5924 loaded value is yielded in all cases. This provides the equivalent of an
5925 atomic compare-and-swap operation within the SSA framework.
5926</p>
5927<h5>Examples:</h5>
5928
5929<pre>
5930%ptr = malloc i32
5931 store i32 4, %ptr
5932
5933%val1 = add i32 4, 4
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]5934%result1 = call i32 @llvm.atomic.cmp.swap.i32.p0i32( i32* %ptr, i32 4, %val1 )
Andrew Lenharthab0b9492008-02-21 06:45:13 +0000[diff] [blame]5935 <i>; yields {i32}:result1 = 4</i>
5936%stored1 = icmp eq i32 %result1, 4 <i>; yields {i1}:stored1 = true</i>
5937%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = 8</i>
5938
5939%val2 = add i32 1, 1
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]5940%result2 = call i32 @llvm.atomic.cmp.swap.i32.p0i32( i32* %ptr, i32 5, %val2 )
Andrew Lenharthab0b9492008-02-21 06:45:13 +0000[diff] [blame]5941 <i>; yields {i32}:result2 = 8</i>
5942%stored2 = icmp eq i32 %result2, 5 <i>; yields {i1}:stored2 = false</i>
5943
5944%memval2 = load i32* %ptr <i>; yields {i32}:memval2 = 8</i>
5945</pre>
5946</div>
5947
5948<!-- _______________________________________________________________________ -->
5949<div class="doc_subsubsection">
5950 <a name="int_atomic_swap">'<tt>llvm.atomic.swap.*</tt>' Intrinsic</a>
5951</div>
5952<div class="doc_text">
5953<h5>Syntax:</h5>
5954
5955<p>
5956 This is an overloaded intrinsic. You can use <tt>llvm.atomic.swap</tt> on any
5957 integer bit width. Not all targets support all bit widths however.</p>
5958<pre>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]5959declare i8 @llvm.atomic.swap.i8.p0i8( i8* &lt;ptr&gt;, i8 &lt;val&gt; )
5960declare i16 @llvm.atomic.swap.i16.p0i16( i16* &lt;ptr&gt;, i16 &lt;val&gt; )
5961declare i32 @llvm.atomic.swap.i32.p0i32( i32* &lt;ptr&gt;, i32 &lt;val&gt; )
5962declare i64 @llvm.atomic.swap.i64.p0i64( i64* &lt;ptr&gt;, i64 &lt;val&gt; )
Andrew Lenharthab0b9492008-02-21 06:45:13 +0000[diff] [blame]5963
5964</pre>
5965<h5>Overview:</h5>
5966<p>
5967 This intrinsic loads the value stored in memory at <tt>ptr</tt> and yields
5968 the value from memory. It then stores the value in <tt>val</tt> in the memory
5969 at <tt>ptr</tt>.
5970</p>
5971<h5>Arguments:</h5>
5972
5973<p>
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]5974 The <tt>llvm.atomic.swap</tt> intrinsic takes two arguments. Both the
Andrew Lenharthab0b9492008-02-21 06:45:13 +0000[diff] [blame]5975 <tt>val</tt> argument and the result must be integers of the same bit width.
5976 The first argument, <tt>ptr</tt>, must be a pointer to a value of this
5977 integer type. The targets may only lower integer representations they
5978 support.
5979</p>
5980<h5>Semantics:</h5>
5981<p>
5982 This intrinsic loads the value pointed to by <tt>ptr</tt>, yields it, and
5983 stores <tt>val</tt> back into <tt>ptr</tt> atomically. This provides the
5984 equivalent of an atomic swap operation within the SSA framework.
5985
5986</p>
5987<h5>Examples:</h5>
5988<pre>
5989%ptr = malloc i32
5990 store i32 4, %ptr
5991
5992%val1 = add i32 4, 4
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]5993%result1 = call i32 @llvm.atomic.swap.i32.p0i32( i32* %ptr, i32 %val1 )
Andrew Lenharthab0b9492008-02-21 06:45:13 +0000[diff] [blame]5994 <i>; yields {i32}:result1 = 4</i>
5995%stored1 = icmp eq i32 %result1, 4 <i>; yields {i1}:stored1 = true</i>
5996%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = 8</i>
5997
5998%val2 = add i32 1, 1
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]5999%result2 = call i32 @llvm.atomic.swap.i32.p0i32( i32* %ptr, i32 %val2 )
Andrew Lenharthab0b9492008-02-21 06:45:13 +0000[diff] [blame]6000 <i>; yields {i32}:result2 = 8</i>
6001
6002%stored2 = icmp eq i32 %result2, 8 <i>; yields {i1}:stored2 = true</i>
6003%memval2 = load i32* %ptr <i>; yields {i32}:memval2 = 2</i>
6004</pre>
6005</div>
6006
6007<!-- _______________________________________________________________________ -->
6008<div class="doc_subsubsection">
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6009 <a name="int_atomic_load_add">'<tt>llvm.atomic.load.add.*</tt>' Intrinsic</a>
Andrew Lenharthab0b9492008-02-21 06:45:13 +0000[diff] [blame]6010
6011</div>
6012<div class="doc_text">
6013<h5>Syntax:</h5>
6014<p>
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6015 This is an overloaded intrinsic. You can use <tt>llvm.atomic.load.add</tt> on any
Andrew Lenharthab0b9492008-02-21 06:45:13 +0000[diff] [blame]6016 integer bit width. Not all targets support all bit widths however.</p>
6017<pre>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6018declare i8 @llvm.atomic.load.add.i8..p0i8( i8* &lt;ptr&gt;, i8 &lt;delta&gt; )
6019declare i16 @llvm.atomic.load.add.i16..p0i16( i16* &lt;ptr&gt;, i16 &lt;delta&gt; )
6020declare i32 @llvm.atomic.load.add.i32..p0i32( i32* &lt;ptr&gt;, i32 &lt;delta&gt; )
6021declare i64 @llvm.atomic.load.add.i64..p0i64( i64* &lt;ptr&gt;, i64 &lt;delta&gt; )
Andrew Lenharthab0b9492008-02-21 06:45:13 +0000[diff] [blame]6022
6023</pre>
6024<h5>Overview:</h5>
6025<p>
6026 This intrinsic adds <tt>delta</tt> to the value stored in memory at
6027 <tt>ptr</tt>. It yields the original value at <tt>ptr</tt>.
6028</p>
6029<h5>Arguments:</h5>
6030<p>
6031
6032 The intrinsic takes two arguments, the first a pointer to an integer value
6033 and the second an integer value. The result is also an integer value. These
6034 integer types can have any bit width, but they must all have the same bit
6035 width. The targets may only lower integer representations they support.
6036</p>
6037<h5>Semantics:</h5>
6038<p>
6039 This intrinsic does a series of operations atomically. It first loads the
6040 value stored at <tt>ptr</tt>. It then adds <tt>delta</tt>, stores the result
6041 to <tt>ptr</tt>. It yields the original value stored at <tt>ptr</tt>.
6042</p>
6043
6044<h5>Examples:</h5>
6045<pre>
6046%ptr = malloc i32
6047 store i32 4, %ptr
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6048%result1 = call i32 @llvm.atomic.load.add.i32.p0i32( i32* %ptr, i32 4 )
Andrew Lenharthab0b9492008-02-21 06:45:13 +0000[diff] [blame]6049 <i>; yields {i32}:result1 = 4</i>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6050%result2 = call i32 @llvm.atomic.load.add.i32.p0i32( i32* %ptr, i32 2 )
Andrew Lenharthab0b9492008-02-21 06:45:13 +0000[diff] [blame]6051 <i>; yields {i32}:result2 = 8</i>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6052%result3 = call i32 @llvm.atomic.load.add.i32.p0i32( i32* %ptr, i32 5 )
Andrew Lenharthab0b9492008-02-21 06:45:13 +0000[diff] [blame]6053 <i>; yields {i32}:result3 = 10</i>
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6054%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = 15</i>
Andrew Lenharthab0b9492008-02-21 06:45:13 +0000[diff] [blame]6055</pre>
6056</div>
6057
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6058<!-- _______________________________________________________________________ -->
6059<div class="doc_subsubsection">
6060 <a name="int_atomic_load_sub">'<tt>llvm.atomic.load.sub.*</tt>' Intrinsic</a>
6061
6062</div>
6063<div class="doc_text">
6064<h5>Syntax:</h5>
6065<p>
6066 This is an overloaded intrinsic. You can use <tt>llvm.atomic.load.sub</tt> on
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6067 any integer bit width and for different address spaces. Not all targets
6068 support all bit widths however.</p>
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6069<pre>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6070declare i8 @llvm.atomic.load.sub.i8.p0i32( i8* &lt;ptr&gt;, i8 &lt;delta&gt; )
6071declare i16 @llvm.atomic.load.sub.i16.p0i32( i16* &lt;ptr&gt;, i16 &lt;delta&gt; )
6072declare i32 @llvm.atomic.load.sub.i32.p0i32( i32* &lt;ptr&gt;, i32 &lt;delta&gt; )
6073declare i64 @llvm.atomic.load.sub.i64.p0i32( i64* &lt;ptr&gt;, i64 &lt;delta&gt; )
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6074
6075</pre>
6076<h5>Overview:</h5>
6077<p>
6078 This intrinsic subtracts <tt>delta</tt> to the value stored in memory at
6079 <tt>ptr</tt>. It yields the original value at <tt>ptr</tt>.
6080</p>
6081<h5>Arguments:</h5>
6082<p>
6083
6084 The intrinsic takes two arguments, the first a pointer to an integer value
6085 and the second an integer value. The result is also an integer value. These
6086 integer types can have any bit width, but they must all have the same bit
6087 width. The targets may only lower integer representations they support.
6088</p>
6089<h5>Semantics:</h5>
6090<p>
6091 This intrinsic does a series of operations atomically. It first loads the
6092 value stored at <tt>ptr</tt>. It then subtracts <tt>delta</tt>, stores the
6093 result to <tt>ptr</tt>. It yields the original value stored at <tt>ptr</tt>.
6094</p>
6095
6096<h5>Examples:</h5>
6097<pre>
6098%ptr = malloc i32
6099 store i32 8, %ptr
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6100%result1 = call i32 @llvm.atomic.load.sub.i32.p0i32( i32* %ptr, i32 4 )
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6101 <i>; yields {i32}:result1 = 8</i>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6102%result2 = call i32 @llvm.atomic.load.sub.i32.p0i32( i32* %ptr, i32 2 )
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6103 <i>; yields {i32}:result2 = 4</i>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6104%result3 = call i32 @llvm.atomic.load.sub.i32.p0i32( i32* %ptr, i32 5 )
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6105 <i>; yields {i32}:result3 = 2</i>
6106%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = -3</i>
6107</pre>
6108</div>
6109
6110<!-- _______________________________________________________________________ -->
6111<div class="doc_subsubsection">
6112 <a name="int_atomic_load_and">'<tt>llvm.atomic.load.and.*</tt>' Intrinsic</a><br>
6113 <a name="int_atomic_load_nand">'<tt>llvm.atomic.load.nand.*</tt>' Intrinsic</a><br>
6114 <a name="int_atomic_load_or">'<tt>llvm.atomic.load.or.*</tt>' Intrinsic</a><br>
6115 <a name="int_atomic_load_xor">'<tt>llvm.atomic.load.xor.*</tt>' Intrinsic</a><br>
6116
6117</div>
6118<div class="doc_text">
6119<h5>Syntax:</h5>
6120<p>
6121 These are overloaded intrinsics. You can use <tt>llvm.atomic.load_and</tt>,
6122 <tt>llvm.atomic.load_nand</tt>, <tt>llvm.atomic.load_or</tt>, and
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6123 <tt>llvm.atomic.load_xor</tt> on any integer bit width and for different
6124 address spaces. Not all targets support all bit widths however.</p>
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6125<pre>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6126declare i8 @llvm.atomic.load.and.i8.p0i8( i8* &lt;ptr&gt;, i8 &lt;delta&gt; )
6127declare i16 @llvm.atomic.load.and.i16.p0i16( i16* &lt;ptr&gt;, i16 &lt;delta&gt; )
6128declare i32 @llvm.atomic.load.and.i32.p0i32( i32* &lt;ptr&gt;, i32 &lt;delta&gt; )
6129declare i64 @llvm.atomic.load.and.i64.p0i64( i64* &lt;ptr&gt;, i64 &lt;delta&gt; )
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6130
6131</pre>
6132
6133<pre>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6134declare i8 @llvm.atomic.load.or.i8.p0i8( i8* &lt;ptr&gt;, i8 &lt;delta&gt; )
6135declare i16 @llvm.atomic.load.or.i16.p0i16( i16* &lt;ptr&gt;, i16 &lt;delta&gt; )
6136declare i32 @llvm.atomic.load.or.i32.p0i32( i32* &lt;ptr&gt;, i32 &lt;delta&gt; )
6137declare i64 @llvm.atomic.load.or.i64.p0i64( i64* &lt;ptr&gt;, i64 &lt;delta&gt; )
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6138
6139</pre>
6140
6141<pre>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6142declare i8 @llvm.atomic.load.nand.i8.p0i32( i8* &lt;ptr&gt;, i8 &lt;delta&gt; )
6143declare i16 @llvm.atomic.load.nand.i16.p0i32( i16* &lt;ptr&gt;, i16 &lt;delta&gt; )
6144declare i32 @llvm.atomic.load.nand.i32.p0i32( i32* &lt;ptr&gt;, i32 &lt;delta&gt; )
6145declare i64 @llvm.atomic.load.nand.i64.p0i32( i64* &lt;ptr&gt;, i64 &lt;delta&gt; )
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6146
6147</pre>
6148
6149<pre>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6150declare i8 @llvm.atomic.load.xor.i8.p0i32( i8* &lt;ptr&gt;, i8 &lt;delta&gt; )
6151declare i16 @llvm.atomic.load.xor.i16.p0i32( i16* &lt;ptr&gt;, i16 &lt;delta&gt; )
6152declare i32 @llvm.atomic.load.xor.i32.p0i32( i32* &lt;ptr&gt;, i32 &lt;delta&gt; )
6153declare i64 @llvm.atomic.load.xor.i64.p0i32( i64* &lt;ptr&gt;, i64 &lt;delta&gt; )
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6154
6155</pre>
6156<h5>Overview:</h5>
6157<p>
6158 These intrinsics bitwise the operation (and, nand, or, xor) <tt>delta</tt> to
6159 the value stored in memory at <tt>ptr</tt>. It yields the original value
6160 at <tt>ptr</tt>.
6161</p>
6162<h5>Arguments:</h5>
6163<p>
6164
6165 These intrinsics take two arguments, the first a pointer to an integer value
6166 and the second an integer value. The result is also an integer value. These
6167 integer types can have any bit width, but they must all have the same bit
6168 width. The targets may only lower integer representations they support.
6169</p>
6170<h5>Semantics:</h5>
6171<p>
6172 These intrinsics does a series of operations atomically. They first load the
6173 value stored at <tt>ptr</tt>. They then do the bitwise operation
6174 <tt>delta</tt>, store the result to <tt>ptr</tt>. They yield the original
6175 value stored at <tt>ptr</tt>.
6176</p>
6177
6178<h5>Examples:</h5>
6179<pre>
6180%ptr = malloc i32
6181 store i32 0x0F0F, %ptr
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6182%result0 = call i32 @llvm.atomic.load.nand.i32.p0i32( i32* %ptr, i32 0xFF )
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6183 <i>; yields {i32}:result0 = 0x0F0F</i>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6184%result1 = call i32 @llvm.atomic.load.and.i32.p0i32( i32* %ptr, i32 0xFF )
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6185 <i>; yields {i32}:result1 = 0xFFFFFFF0</i>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6186%result2 = call i32 @llvm.atomic.load.or.i32.p0i32( i32* %ptr, i32 0F )
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6187 <i>; yields {i32}:result2 = 0xF0</i>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6188%result3 = call i32 @llvm.atomic.load.xor.i32.p0i32( i32* %ptr, i32 0F )
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6189 <i>; yields {i32}:result3 = FF</i>
6190%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = F0</i>
6191</pre>
6192</div>
6193
6194
6195<!-- _______________________________________________________________________ -->
6196<div class="doc_subsubsection">
6197 <a name="int_atomic_load_max">'<tt>llvm.atomic.load.max.*</tt>' Intrinsic</a><br>
6198 <a name="int_atomic_load_min">'<tt>llvm.atomic.load.min.*</tt>' Intrinsic</a><br>
6199 <a name="int_atomic_load_umax">'<tt>llvm.atomic.load.umax.*</tt>' Intrinsic</a><br>
6200 <a name="int_atomic_load_umin">'<tt>llvm.atomic.load.umin.*</tt>' Intrinsic</a><br>
6201
6202</div>
6203<div class="doc_text">
6204<h5>Syntax:</h5>
6205<p>
6206 These are overloaded intrinsics. You can use <tt>llvm.atomic.load_max</tt>,
6207 <tt>llvm.atomic.load_min</tt>, <tt>llvm.atomic.load_umax</tt>, and
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6208 <tt>llvm.atomic.load_umin</tt> on any integer bit width and for different
6209 address spaces. Not all targets
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6210 support all bit widths however.</p>
6211<pre>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6212declare i8 @llvm.atomic.load.max.i8.p0i8( i8* &lt;ptr&gt;, i8 &lt;delta&gt; )
6213declare i16 @llvm.atomic.load.max.i16.p0i16( i16* &lt;ptr&gt;, i16 &lt;delta&gt; )
6214declare i32 @llvm.atomic.load.max.i32.p0i32( i32* &lt;ptr&gt;, i32 &lt;delta&gt; )
6215declare i64 @llvm.atomic.load.max.i64.p0i64( i64* &lt;ptr&gt;, i64 &lt;delta&gt; )
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6216
6217</pre>
6218
6219<pre>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6220declare i8 @llvm.atomic.load.min.i8.p0i8( i8* &lt;ptr&gt;, i8 &lt;delta&gt; )
6221declare i16 @llvm.atomic.load.min.i16.p0i16( i16* &lt;ptr&gt;, i16 &lt;delta&gt; )
6222declare i32 @llvm.atomic.load.min.i32..p0i32( i32* &lt;ptr&gt;, i32 &lt;delta&gt; )
6223declare i64 @llvm.atomic.load.min.i64..p0i64( i64* &lt;ptr&gt;, i64 &lt;delta&gt; )
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6224
6225</pre>
6226
6227<pre>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6228declare i8 @llvm.atomic.load.umax.i8.p0i8( i8* &lt;ptr&gt;, i8 &lt;delta&gt; )
6229declare i16 @llvm.atomic.load.umax.i16.p0i16( i16* &lt;ptr&gt;, i16 &lt;delta&gt; )
6230declare i32 @llvm.atomic.load.umax.i32.p0i32( i32* &lt;ptr&gt;, i32 &lt;delta&gt; )
6231declare i64 @llvm.atomic.load.umax.i64.p0i64( i64* &lt;ptr&gt;, i64 &lt;delta&gt; )
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6232
6233</pre>
6234
6235<pre>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6236declare i8 @llvm.atomic.load.umin.i8..p0i8( i8* &lt;ptr&gt;, i8 &lt;delta&gt; )
6237declare i16 @llvm.atomic.load.umin.i16.p0i16( i16* &lt;ptr&gt;, i16 &lt;delta&gt; )
6238declare i32 @llvm.atomic.load.umin.i32..p0i32( i32* &lt;ptr&gt;, i32 &lt;delta&gt; )
6239declare i64 @llvm.atomic.load.umin.i64..p0i64( i64* &lt;ptr&gt;, i64 &lt;delta&gt; )
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6240
6241</pre>
6242<h5>Overview:</h5>
6243<p>
6244 These intrinsics takes the signed or unsigned minimum or maximum of
6245 <tt>delta</tt> and the value stored in memory at <tt>ptr</tt>. It yields the
6246 original value at <tt>ptr</tt>.
6247</p>
6248<h5>Arguments:</h5>
6249<p>
6250
6251 These intrinsics take two arguments, the first a pointer to an integer value
6252 and the second an integer value. The result is also an integer value. These
6253 integer types can have any bit width, but they must all have the same bit
6254 width. The targets may only lower integer representations they support.
6255</p>
6256<h5>Semantics:</h5>
6257<p>
6258 These intrinsics does a series of operations atomically. They first load the
6259 value stored at <tt>ptr</tt>. They then do the signed or unsigned min or max
6260 <tt>delta</tt> and the value, store the result to <tt>ptr</tt>. They yield
6261 the original value stored at <tt>ptr</tt>.
6262</p>
6263
6264<h5>Examples:</h5>
6265<pre>
6266%ptr = malloc i32
6267 store i32 7, %ptr
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6268%result0 = call i32 @llvm.atomic.load.min.i32.p0i32( i32* %ptr, i32 -2 )
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6269 <i>; yields {i32}:result0 = 7</i>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6270%result1 = call i32 @llvm.atomic.load.max.i32.p0i32( i32* %ptr, i32 8 )
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6271 <i>; yields {i32}:result1 = -2</i>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6272%result2 = call i32 @llvm.atomic.load.umin.i32.p0i32( i32* %ptr, i32 10 )
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6273 <i>; yields {i32}:result2 = 8</i>
Mon P Wange3b3a722008-07-30 04:36:53 +0000[diff] [blame]6274%result3 = call i32 @llvm.atomic.load.umax.i32.p0i32( i32* %ptr, i32 30 )
Mon P Wang28873102008-06-25 08:15:39 +0000[diff] [blame]6275 <i>; yields {i32}:result3 = 8</i>
6276%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = 30</i>
6277</pre>
6278</div>
Andrew Lenharth22c5c1b2008-02-16 01:24:58 +0000[diff] [blame]6279
6280<!-- ======================================================================= -->
6281<div class="doc_subsection">
Tanya Lattner6d806e92007-06-15 20:50:54 +0000[diff] [blame]6282 <a name="int_general">General Intrinsics</a>
6283</div>
6284
6285<div class="doc_text">
6286<p> This class of intrinsics is designed to be generic and has
6287no specific purpose. </p>
6288</div>
6289
6290<!-- _______________________________________________________________________ -->
6291<div class="doc_subsubsection">
6292 <a name="int_var_annotation">'<tt>llvm.var.annotation</tt>' Intrinsic</a>
6293</div>
6294
6295<div class="doc_text">
6296
6297<h5>Syntax:</h5>
6298<pre>
Tanya Lattnerd2e84422007-06-18 23:42:37 +0000[diff] [blame]6299 declare void @llvm.var.annotation(i8* &lt;val&gt;, i8* &lt;str&gt;, i8* &lt;str&gt;, i32 &lt;int&gt; )
Tanya Lattner6d806e92007-06-15 20:50:54 +0000[diff] [blame]6300</pre>
6301
6302<h5>Overview:</h5>
6303
6304<p>
6305The '<tt>llvm.var.annotation</tt>' intrinsic
6306</p>
6307
6308<h5>Arguments:</h5>
6309
6310<p>
Tanya Lattnerd2e84422007-06-18 23:42:37 +0000[diff] [blame]6311The first argument is a pointer to a value, the second is a pointer to a
6312global string, the third is a pointer to a global string which is the source
6313file name, and the last argument is the line number.
Tanya Lattner6d806e92007-06-15 20:50:54 +0000[diff] [blame]6314</p>
6315
6316<h5>Semantics:</h5>
6317
6318<p>
Anton Korobeynikov4cb86182008-01-15 22:31:34 +0000[diff] [blame]6319This intrinsic allows annotation of local variables with arbitrary strings.
Tanya Lattner6d806e92007-06-15 20:50:54 +0000[diff] [blame]6320This can be useful for special purpose optimizations that want to look for these
Anton Korobeynikov4cb86182008-01-15 22:31:34 +0000[diff] [blame]6321annotations. These have no other defined use, they are ignored by code
6322generation and optimization.
6323</p>
Tanya Lattner6d806e92007-06-15 20:50:54 +0000[diff] [blame]6324</div>
6325
Tanya Lattnerb6367882007-09-21 22:59:12 +0000[diff] [blame]6326<!-- _______________________________________________________________________ -->
6327<div class="doc_subsubsection">
Tanya Lattnere1a8da02007-09-21 23:57:59 +0000[diff] [blame]6328 <a name="int_annotation">'<tt>llvm.annotation.*</tt>' Intrinsic</a>
Tanya Lattnerb6367882007-09-21 22:59:12 +0000[diff] [blame]6329</div>
6330
6331<div class="doc_text">
6332
6333<h5>Syntax:</h5>
Tanya Lattner39cfba62007-09-21 23:56:27 +0000[diff] [blame]6334<p>This is an overloaded intrinsic. You can use '<tt>llvm.annotation</tt>' on
6335any integer bit width.
6336</p>
Tanya Lattnerb6367882007-09-21 22:59:12 +0000[diff] [blame]6337<pre>
Tanya Lattnerd3989a82007-09-22 00:03:01 +0000[diff] [blame]6338 declare i8 @llvm.annotation.i8(i8 &lt;val&gt;, i8* &lt;str&gt;, i8* &lt;str&gt;, i32 &lt;int&gt; )
6339 declare i16 @llvm.annotation.i16(i16 &lt;val&gt;, i8* &lt;str&gt;, i8* &lt;str&gt;, i32 &lt;int&gt; )
6340 declare i32 @llvm.annotation.i32(i32 &lt;val&gt;, i8* &lt;str&gt;, i8* &lt;str&gt;, i32 &lt;int&gt; )
6341 declare i64 @llvm.annotation.i64(i64 &lt;val&gt;, i8* &lt;str&gt;, i8* &lt;str&gt;, i32 &lt;int&gt; )
6342 declare i256 @llvm.annotation.i256(i256 &lt;val&gt;, i8* &lt;str&gt;, i8* &lt;str&gt;, i32 &lt;int&gt; )
Tanya Lattnerb6367882007-09-21 22:59:12 +0000[diff] [blame]6343</pre>
6344
6345<h5>Overview:</h5>
Tanya Lattner39cfba62007-09-21 23:56:27 +0000[diff] [blame]6346
6347<p>
6348The '<tt>llvm.annotation</tt>' intrinsic.
Tanya Lattnerb6367882007-09-21 22:59:12 +0000[diff] [blame]6349</p>
6350
6351<h5>Arguments:</h5>
6352
6353<p>
6354The first argument is an integer value (result of some expression),
6355the second is a pointer to a global string, the third is a pointer to a global
6356string which is the source file name, and the last argument is the line number.
Tanya Lattner39cfba62007-09-21 23:56:27 +0000[diff] [blame]6357It returns the value of the first argument.
Tanya Lattnerb6367882007-09-21 22:59:12 +0000[diff] [blame]6358</p>
6359
6360<h5>Semantics:</h5>
6361
6362<p>
6363This intrinsic allows annotations to be put on arbitrary expressions
6364with arbitrary strings. This can be useful for special purpose optimizations
6365that want to look for these annotations. These have no other defined use, they
6366are ignored by code generation and optimization.
Dan Gohman0e451ce2008-10-14 16:51:45 +0000[diff] [blame^]6367</p>
Tanya Lattnerb6367882007-09-21 22:59:12 +0000[diff] [blame]6368</div>
Jim Laskeydd4ef1b2007-03-14 19:31:19 +0000[diff] [blame]6369
Anton Korobeynikov4cb86182008-01-15 22:31:34 +0000[diff] [blame]6370<!-- _______________________________________________________________________ -->
6371<div class="doc_subsubsection">
6372 <a name="int_trap">'<tt>llvm.trap</tt>' Intrinsic</a>
6373</div>
6374
6375<div class="doc_text">
6376
6377<h5>Syntax:</h5>
6378<pre>
6379 declare void @llvm.trap()
6380</pre>
6381
6382<h5>Overview:</h5>
6383
6384<p>
6385The '<tt>llvm.trap</tt>' intrinsic
6386</p>
6387
6388<h5>Arguments:</h5>
6389
6390<p>
6391None
6392</p>
6393
6394<h5>Semantics:</h5>
6395
6396<p>
6397This intrinsics is lowered to the target dependent trap instruction. If the
6398target does not have a trap instruction, this intrinsic will be lowered to the
6399call of the abort() function.
6400</p>
6401</div>
6402
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]6403<!-- *********************************************************************** -->
Chris Lattner00950542001-06-06 20:29:01 +0000[diff] [blame]6404<hr>
Misha Brukmandaa4cb02004-03-01 17:47:27 +0000[diff] [blame]6405<address>
6406 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
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Misha Brukmandaa4cb02004-03-01 17:47:27 +0000[diff] [blame]6410
6411 <a href="mailto:sabre@nondot.org">Chris Lattner</a><br>
Reid Spencer05fe4b02006-03-14 05:39:39 +0000[diff] [blame]6412 <a href="http://llvm.org">The LLVM Compiler Infrastructure</a><br>
Misha Brukmandaa4cb02004-03-01 17:47:27 +0000[diff] [blame]6413 Last modified: $Date$
6414</address>
Chris Lattnerc7d3ab32008-01-04 04:33:49 +0000[diff] [blame]6415
Misha Brukman9d0919f2003-11-08 01:05:38 +0000[diff] [blame]6416</body>
6417</html>