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NAKAMURA Takumifc8d9302011-04-18 23:59:50 +000011<h1>Source Level Debugging with LLVM</h1>
Chris Lattner1811fca2004-01-05 05:06:33 +000012
Reid Spencerc3c4c4f2004-11-01 08:19:36 +000013<table class="layout" style="width:100%">
14 <tr class="layout">
15 <td class="left">
Chris Lattner1811fca2004-01-05 05:06:33 +000016<ul>
Misha Brukmanf91d9942004-05-12 19:21:57 +000017 <li><a href="#introduction">Introduction</a>
Chris Lattner1811fca2004-01-05 05:06:33 +000018 <ol>
19 <li><a href="#phil">Philosophy behind LLVM debugging information</a></li>
Jim Laskey5dcfd562006-03-23 17:54:33 +000020 <li><a href="#consumers">Debug information consumers</a></li>
Chris Lattner1811fca2004-01-05 05:06:33 +000021 <li><a href="#debugopt">Debugging optimized code</a></li>
Misha Brukmanf91d9942004-05-12 19:21:57 +000022 </ol></li>
Misha Brukmanf91d9942004-05-12 19:21:57 +000023 <li><a href="#format">Debugging information format</a>
Chris Lattner1811fca2004-01-05 05:06:33 +000024 <ol>
Jim Laskey14edc932006-03-14 18:08:46 +000025 <li><a href="#debug_info_descriptors">Debug information descriptors</a>
Chris Lattner1811fca2004-01-05 05:06:33 +000026 <ul>
Jim Laskey14edc932006-03-14 18:08:46 +000027 <li><a href="#format_compile_units">Compile unit descriptors</a></li>
Devang Patel59445db2010-03-09 00:44:10 +000028 <li><a href="#format_files">File descriptors</a></li>
Jim Laskey14edc932006-03-14 18:08:46 +000029 <li><a href="#format_global_variables">Global variable descriptors</a></li>
30 <li><a href="#format_subprograms">Subprogram descriptors</a></li>
Jim Laskey9dcffe72006-03-15 19:10:52 +000031 <li><a href="#format_blocks">Block descriptors</a></li>
Jim Laskey14edc932006-03-14 18:08:46 +000032 <li><a href="#format_basic_type">Basic type descriptors</a></li>
33 <li><a href="#format_derived_type">Derived type descriptors</a></li>
34 <li><a href="#format_composite_type">Composite type descriptors</a></li>
35 <li><a href="#format_subrange">Subrange descriptors</a></li>
36 <li><a href="#format_enumeration">Enumerator descriptors</a></li>
Jim Laskey5dcfd562006-03-23 17:54:33 +000037 <li><a href="#format_variables">Local variables</a></li>
Misha Brukmanf91d9942004-05-12 19:21:57 +000038 </ul></li>
Jim Laskey14edc932006-03-14 18:08:46 +000039 <li><a href="#format_common_intrinsics">Debugger intrinsic functions</a>
40 <ul>
Jim Laskey14edc932006-03-14 18:08:46 +000041 <li><a href="#format_common_declare">llvm.dbg.declare</a></li>
Victor Hernandez0b62cc62010-01-11 22:53:48 +000042 <li><a href="#format_common_value">llvm.dbg.value</a></li>
Jim Laskey14edc932006-03-14 18:08:46 +000043 </ul></li>
Misha Brukmanf91d9942004-05-12 19:21:57 +000044 </ol></li>
Devang Patel4da997b2009-11-25 23:28:01 +000045 <li><a href="#format_common_lifetime">Object lifetimes and scoping</a></li>
Misha Brukmanf91d9942004-05-12 19:21:57 +000046 <li><a href="#ccxx_frontend">C/C++ front-end specific debug information</a>
Chris Lattner1811fca2004-01-05 05:06:33 +000047 <ol>
Jim Laskey14edc932006-03-14 18:08:46 +000048 <li><a href="#ccxx_compile_units">C/C++ source file information</a></li>
49 <li><a href="#ccxx_global_variable">C/C++ global variable information</a></li>
50 <li><a href="#ccxx_subprogram">C/C++ function information</a></li>
51 <li><a href="#ccxx_basic_types">C/C++ basic types</a></li>
52 <li><a href="#ccxx_derived_types">C/C++ derived types</a></li>
53 <li><a href="#ccxx_composite_types">C/C++ struct/union types</a></li>
54 <li><a href="#ccxx_enumeration_types">C/C++ enumeration types</a></li>
Misha Brukmanf91d9942004-05-12 19:21:57 +000055 </ol></li>
Chris Lattner1811fca2004-01-05 05:06:33 +000056</ul>
Misha Brukmanf91d9942004-05-12 19:21:57 +000057</td>
Reid Spencerc3c4c4f2004-11-01 08:19:36 +000058<td class="right">
Misha Brukman3c1f8e72004-05-12 21:26:16 +000059<img src="img/venusflytrap.jpg" alt="A leafy and green bug eater" width="247"
Misha Brukmanf91d9942004-05-12 19:21:57 +000060height="369">
61</td>
Reid Spencerc3c4c4f2004-11-01 08:19:36 +000062</tr></table>
Misha Brukmanf91d9942004-05-12 19:21:57 +000063
Chris Lattner020e1fc2004-05-23 21:07:27 +000064<div class="doc_author">
Jim Laskey14edc932006-03-14 18:08:46 +000065 <p>Written by <a href="mailto:sabre@nondot.org">Chris Lattner</a>
Jim Laskey6e8a2f42007-03-14 19:32:21 +000066 and <a href="mailto:jlaskey@mac.com">Jim Laskey</a></p>
Chris Lattner020e1fc2004-05-23 21:07:27 +000067</div>
68
Chris Lattner1811fca2004-01-05 05:06:33 +000069
70<!-- *********************************************************************** -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +000071<h2><a name="introduction">Introduction</a></h2>
Misha Brukmancda6a9b2004-12-09 20:27:37 +000072<!-- *********************************************************************** -->
Chris Lattner1811fca2004-01-05 05:06:33 +000073
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +000074<div>
Chris Lattner1811fca2004-01-05 05:06:33 +000075
76<p>This document is the central repository for all information pertaining to
Bill Wendlinge9353d72009-05-17 05:52:39 +000077 debug information in LLVM. It describes the <a href="#format">actual format
78 that the LLVM debug information</a> takes, which is useful for those
79 interested in creating front-ends or dealing directly with the information.
Chris Lattnercb3f64f2009-07-18 21:47:15 +000080 Further, this document provides specific examples of what debug information
Chris Lattner92ec3d12011-01-18 06:12:10 +000081 for C/C++ looks like.</p>
Chris Lattner1811fca2004-01-05 05:06:33 +000082
Chris Lattner1811fca2004-01-05 05:06:33 +000083<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +000084<h3>
Chris Lattner1811fca2004-01-05 05:06:33 +000085 <a name="phil">Philosophy behind LLVM debugging information</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +000086</h3>
Chris Lattner1811fca2004-01-05 05:06:33 +000087
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +000088<div>
Chris Lattner1811fca2004-01-05 05:06:33 +000089
Misha Brukmanf91d9942004-05-12 19:21:57 +000090<p>The idea of the LLVM debugging information is to capture how the important
Bill Wendlinge9353d72009-05-17 05:52:39 +000091 pieces of the source-language's Abstract Syntax Tree map onto LLVM code.
92 Several design aspects have shaped the solution that appears here. The
93 important ones are:</p>
Chris Lattner1811fca2004-01-05 05:06:33 +000094
Misha Brukmanf91d9942004-05-12 19:21:57 +000095<ul>
Bill Wendlinge9353d72009-05-17 05:52:39 +000096 <li>Debugging information should have very little impact on the rest of the
97 compiler. No transformations, analyses, or code generators should need to
98 be modified because of debugging information.</li>
Chris Lattner1811fca2004-01-05 05:06:33 +000099
Bill Wendlinge9353d72009-05-17 05:52:39 +0000100 <li>LLVM optimizations should interact in <a href="#debugopt">well-defined and
101 easily described ways</a> with the debugging information.</li>
Chris Lattner1811fca2004-01-05 05:06:33 +0000102
Bill Wendlinge9353d72009-05-17 05:52:39 +0000103 <li>Because LLVM is designed to support arbitrary programming languages,
104 LLVM-to-LLVM tools should not need to know anything about the semantics of
105 the source-level-language.</li>
Chris Lattner1811fca2004-01-05 05:06:33 +0000106
Bill Wendlinge9353d72009-05-17 05:52:39 +0000107 <li>Source-level languages are often <b>widely</b> different from one another.
108 LLVM should not put any restrictions of the flavor of the source-language,
109 and the debugging information should work with any language.</li>
Chris Lattner1811fca2004-01-05 05:06:33 +0000110
Bill Wendlinge9353d72009-05-17 05:52:39 +0000111 <li>With code generator support, it should be possible to use an LLVM compiler
112 to compile a program to native machine code and standard debugging
113 formats. This allows compatibility with traditional machine-code level
114 debuggers, like GDB or DBX.</li>
Misha Brukmanf91d9942004-05-12 19:21:57 +0000115</ul>
Chris Lattner1811fca2004-01-05 05:06:33 +0000116
Bill Wendlinge9353d72009-05-17 05:52:39 +0000117<p>The approach used by the LLVM implementation is to use a small set
118 of <a href="#format_common_intrinsics">intrinsic functions</a> to define a
119 mapping between LLVM program objects and the source-level objects. The
Devang Patel80ae3492009-08-28 23:24:31 +0000120 description of the source-level program is maintained in LLVM metadata
121 in an <a href="#ccxx_frontend">implementation-defined format</a>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000122 (the C/C++ front-end currently uses working draft 7 of
123 the <a href="http://www.eagercon.com/dwarf/dwarf3std.htm">DWARF 3
124 standard</a>).</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000125
Jim Laskey14edc932006-03-14 18:08:46 +0000126<p>When a program is being debugged, a debugger interacts with the user and
Bill Wendlinge9353d72009-05-17 05:52:39 +0000127 turns the stored debug information into source-language specific information.
128 As such, a debugger must be aware of the source-language, and is thus tied to
129 a specific language or family of languages.</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000130
131</div>
132
Chris Lattner1811fca2004-01-05 05:06:33 +0000133<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000134<h3>
Jim Laskey5dcfd562006-03-23 17:54:33 +0000135 <a name="consumers">Debug information consumers</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000136</h3>
Jim Laskey5dcfd562006-03-23 17:54:33 +0000137
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000138<div>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000139
Jim Laskey5dcfd562006-03-23 17:54:33 +0000140<p>The role of debug information is to provide meta information normally
Bill Wendlinge9353d72009-05-17 05:52:39 +0000141 stripped away during the compilation process. This meta information provides
142 an LLVM user a relationship between generated code and the original program
143 source code.</p>
Jim Laskey5dcfd562006-03-23 17:54:33 +0000144
Chris Lattner904f2172010-04-05 04:11:11 +0000145<p>Currently, debug information is consumed by DwarfDebug to produce dwarf
Bill Wendlinge9353d72009-05-17 05:52:39 +0000146 information used by the gdb debugger. Other targets could use the same
147 information to produce stabs or other debug forms.</p>
Jim Laskey5dcfd562006-03-23 17:54:33 +0000148
149<p>It would also be reasonable to use debug information to feed profiling tools
Bill Wendlinge9353d72009-05-17 05:52:39 +0000150 for analysis of generated code, or, tools for reconstructing the original
151 source from generated code.</p>
Jim Laskey5dcfd562006-03-23 17:54:33 +0000152
153<p>TODO - expound a bit more.</p>
154
155</div>
156
157<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000158<h3>
Chris Lattner1811fca2004-01-05 05:06:33 +0000159 <a name="debugopt">Debugging optimized code</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000160</h3>
Chris Lattner1811fca2004-01-05 05:06:33 +0000161
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000162<div>
Chris Lattner1811fca2004-01-05 05:06:33 +0000163
Misha Brukmanf91d9942004-05-12 19:21:57 +0000164<p>An extremely high priority of LLVM debugging information is to make it
Bill Wendlinge9353d72009-05-17 05:52:39 +0000165 interact well with optimizations and analysis. In particular, the LLVM debug
166 information provides the following guarantees:</p>
Misha Brukmanf91d9942004-05-12 19:21:57 +0000167
168<ul>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000169 <li>LLVM debug information <b>always provides information to accurately read
170 the source-level state of the program</b>, regardless of which LLVM
171 optimizations have been run, and without any modification to the
172 optimizations themselves. However, some optimizations may impact the
173 ability to modify the current state of the program with a debugger, such
174 as setting program variables, or calling functions that have been
175 deleted.</li>
Chris Lattner1811fca2004-01-05 05:06:33 +0000176
Bill Wendlinge9353d72009-05-17 05:52:39 +0000177 <li>As desired, LLVM optimizations can be upgraded to be aware of the LLVM
178 debugging information, allowing them to update the debugging information
179 as they perform aggressive optimizations. This means that, with effort,
180 the LLVM optimizers could optimize debug code just as well as non-debug
181 code.</li>
Chris Lattner1811fca2004-01-05 05:06:33 +0000182
Devang Patel5c26a852011-05-31 17:45:27 +0000183 <li>LLVM debug information does not prevent optimizations from
Bill Wendlinge9353d72009-05-17 05:52:39 +0000184 happening (for example inlining, basic block reordering/merging/cleanup,
Devang Patel1d81ea82011-05-31 18:06:14 +0000185 tail duplication, etc).</li>
Chris Lattner1811fca2004-01-05 05:06:33 +0000186
Bill Wendlinge9353d72009-05-17 05:52:39 +0000187 <li>LLVM debug information is automatically optimized along with the rest of
188 the program, using existing facilities. For example, duplicate
189 information is automatically merged by the linker, and unused information
190 is automatically removed.</li>
Misha Brukmanf91d9942004-05-12 19:21:57 +0000191</ul>
Chris Lattner1811fca2004-01-05 05:06:33 +0000192
Misha Brukmanf91d9942004-05-12 19:21:57 +0000193<p>Basically, the debug information allows you to compile a program with
Bill Wendlinge9353d72009-05-17 05:52:39 +0000194 "<tt>-O0 -g</tt>" and get full debug information, allowing you to arbitrarily
195 modify the program as it executes from a debugger. Compiling a program with
196 "<tt>-O3 -g</tt>" gives you full debug information that is always available
197 and accurate for reading (e.g., you get accurate stack traces despite tail
198 call elimination and inlining), but you might lose the ability to modify the
199 program and call functions where were optimized out of the program, or
200 inlined away completely.</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000201
Misha Brukman39dcddf2008-12-16 02:54:22 +0000202<p><a href="TestingGuide.html#quicktestsuite">LLVM test suite</a> provides a
Bill Wendlinge9353d72009-05-17 05:52:39 +0000203 framework to test optimizer's handling of debugging information. It can be
204 run like this:</p>
Devang Patelb885a912008-11-21 19:35:57 +0000205
206<div class="doc_code">
207<pre>
208% cd llvm/projects/test-suite/MultiSource/Benchmarks # or some other level
209% make TEST=dbgopt
210</pre>
211</div>
212
Bill Wendlinge9353d72009-05-17 05:52:39 +0000213<p>This will test impact of debugging information on optimization passes. If
214 debugging information influences optimization passes then it will be reported
215 as a failure. See <a href="TestingGuide.html">TestingGuide</a> for more
216 information on LLVM test infrastructure and how to run various tests.</p>
Devang Patelb885a912008-11-21 19:35:57 +0000217
Chris Lattner1811fca2004-01-05 05:06:33 +0000218</div>
219
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000220</div>
221
Chris Lattner1811fca2004-01-05 05:06:33 +0000222<!-- *********************************************************************** -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000223<h2>
Chris Lattner941515c2004-01-06 05:31:32 +0000224 <a name="format">Debugging information format</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000225</h2>
Chris Lattner1811fca2004-01-05 05:06:33 +0000226<!-- *********************************************************************** -->
227
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000228<div>
Chris Lattner1811fca2004-01-05 05:06:33 +0000229
230<p>LLVM debugging information has been carefully designed to make it possible
Bill Wendlinge9353d72009-05-17 05:52:39 +0000231 for the optimizer to optimize the program and debugging information without
232 necessarily having to know anything about debugging information. In
John Criswell2a4b0802010-03-17 15:01:50 +0000233 particular, the use of metadata avoids duplicated debugging information from
Devang Patel80ae3492009-08-28 23:24:31 +0000234 the beginning, and the global dead code elimination pass automatically
235 deletes debugging information for a function if it decides to delete the
236 function. </p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000237
238<p>To do this, most of the debugging information (descriptors for types,
Bill Wendlinge9353d72009-05-17 05:52:39 +0000239 variables, functions, source files, etc) is inserted by the language
Devang Patel80ae3492009-08-28 23:24:31 +0000240 front-end in the form of LLVM metadata. </p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000241
Jim Laskey14edc932006-03-14 18:08:46 +0000242<p>Debug information is designed to be agnostic about the target debugger and
Bill Wendlinge9353d72009-05-17 05:52:39 +0000243 debugging information representation (e.g. DWARF/Stabs/etc). It uses a
Devang Patel80ae3492009-08-28 23:24:31 +0000244 generic pass to decode the information that represents variables, types,
245 functions, namespaces, etc: this allows for arbitrary source-language
246 semantics and type-systems to be used, as long as there is a module
247 written for the target debugger to interpret the information. </p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000248
Misha Brukmanf91d9942004-05-12 19:21:57 +0000249<p>To provide basic functionality, the LLVM debugger does have to make some
Bill Wendlinge9353d72009-05-17 05:52:39 +0000250 assumptions about the source-level language being debugged, though it keeps
251 these to a minimum. The only common features that the LLVM debugger assumes
Devang Patel59445db2010-03-09 00:44:10 +0000252 exist are <a href="#format_files">source files</a>,
Bill Wendlinge9353d72009-05-17 05:52:39 +0000253 and <a href="#format_global_variables">program objects</a>. These abstract
254 objects are used by a debugger to form stack traces, show information about
255 local variables, etc.</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000256
257<p>This section of the documentation first describes the representation aspects
Bill Wendlinge9353d72009-05-17 05:52:39 +0000258 common to any source-language. The <a href="#ccxx_frontend">next section</a>
259 describes the data layout conventions used by the C and C++ front-ends.</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000260
Chris Lattner1811fca2004-01-05 05:06:33 +0000261<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000262<h3>
Jim Laskey14edc932006-03-14 18:08:46 +0000263 <a name="debug_info_descriptors">Debug information descriptors</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000264</h3>
Chris Lattner1811fca2004-01-05 05:06:33 +0000265
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000266<div>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000267
Jim Laskey14edc932006-03-14 18:08:46 +0000268<p>In consideration of the complexity and volume of debug information, LLVM
Devang Patel80ae3492009-08-28 23:24:31 +0000269 provides a specification for well formed debug descriptors. </p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000270
Jim Laskey14edc932006-03-14 18:08:46 +0000271<p>Consumers of LLVM debug information expect the descriptors for program
Bill Wendlinge9353d72009-05-17 05:52:39 +0000272 objects to start in a canonical format, but the descriptors can include
273 additional information appended at the end that is source-language
274 specific. All LLVM debugging information is versioned, allowing backwards
275 compatibility in the case that the core structures need to change in some
276 way. Also, all debugging information objects start with a tag to indicate
277 what type of object it is. The source-language is allowed to define its own
278 objects, by using unreserved tag numbers. We recommend using with tags in
Benjamin Kramer0f420382009-10-12 14:46:08 +0000279 the range 0x1000 through 0x2000 (there is a defined enum DW_TAG_user_base =
Bill Wendlinge9353d72009-05-17 05:52:39 +0000280 0x1000.)</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000281
Devang Patel80ae3492009-08-28 23:24:31 +0000282<p>The fields of debug descriptors used internally by LLVM
Nick Lewyckya87014f2010-03-31 07:50:17 +0000283 are restricted to only the simple data types <tt>i32</tt>, <tt>i1</tt>,
284 <tt>float</tt>, <tt>double</tt>, <tt>mdstring</tt> and <tt>mdnode</tt>. </p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000285
Bill Wendlinge9353d72009-05-17 05:52:39 +0000286<div class="doc_code">
Misha Brukmanf91d9942004-05-12 19:21:57 +0000287<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000288!1 = metadata !{
Nick Lewyckya87014f2010-03-31 07:50:17 +0000289 i32, ;; A tag
Bill Wendlinge9353d72009-05-17 05:52:39 +0000290 ...
291}
Misha Brukmanf91d9942004-05-12 19:21:57 +0000292</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000293</div>
Chris Lattner1811fca2004-01-05 05:06:33 +0000294
Jim Laskeyb2ff2d42006-06-16 13:14:03 +0000295<p><a name="LLVMDebugVersion">The first field of a descriptor is always an
Nick Lewyckya87014f2010-03-31 07:50:17 +0000296 <tt>i32</tt> containing a tag value identifying the content of the
Bill Wendlinge9353d72009-05-17 05:52:39 +0000297 descriptor. The remaining fields are specific to the descriptor. The values
298 of tags are loosely bound to the tag values of DWARF information entries.
299 However, that does not restrict the use of the information supplied to DWARF
300 targets. To facilitate versioning of debug information, the tag is augmented
Nick Lewyckyf6e37112011-07-25 21:13:23 +0000301 with the current debug version (LLVMDebugVersion = 8 &lt;&lt; 16 or
302 0x80000 or 524288.)</a></p>
Jim Laskey14edc932006-03-14 18:08:46 +0000303
Jim Laskeyb2ff2d42006-06-16 13:14:03 +0000304<p>The details of the various descriptors follow.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000305
Jim Laskey14edc932006-03-14 18:08:46 +0000306<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000307<h4>
Jim Laskey14edc932006-03-14 18:08:46 +0000308 <a name="format_compile_units">Compile unit descriptors</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000309</h4>
Jim Laskey14edc932006-03-14 18:08:46 +0000310
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000311<div>
Jim Laskey14edc932006-03-14 18:08:46 +0000312
Bill Wendlinge9353d72009-05-17 05:52:39 +0000313<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000314<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000315!0 = metadata !{
316 i32, ;; Tag = 17 + <a href="#LLVMDebugVersion">LLVMDebugVersion</a>
317 ;; (DW_TAG_compile_unit)
318 i32, ;; Unused field.
319 i32, ;; DWARF language identifier (ex. DW_LANG_C89)
320 metadata, ;; Source file name
321 metadata, ;; Source file directory (includes trailing slash)
322 metadata ;; Producer (ex. "4.0.1 LLVM (LLVM research group)")
323 i1, ;; True if this is a main compile unit.
324 i1, ;; True if this is optimized.
325 metadata, ;; Flags
326 i32 ;; Runtime version
Bill Wendlinge9353d72009-05-17 05:52:39 +0000327}
Jim Laskey14edc932006-03-14 18:08:46 +0000328</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000329</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000330
Bill Wendlinge9353d72009-05-17 05:52:39 +0000331<p>These descriptors contain a source language ID for the file (we use the DWARF
332 3.0 ID numbers, such as <tt>DW_LANG_C89</tt>, <tt>DW_LANG_C_plus_plus</tt>,
333 <tt>DW_LANG_Cobol74</tt>, etc), three strings describing the filename,
334 working directory of the compiler, and an identifier string for the compiler
335 that produced it.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000336
Bill Wendlinge9353d72009-05-17 05:52:39 +0000337<p>Compile unit descriptors provide the root context for objects declared in a
Devang Patel09fa69e2011-05-03 16:18:28 +0000338 specific compilation unit. File descriptors are defined using this context.
339 These descriptors are collected by a named metadata
340 <tt>!llvm.dbg.cu</tt>.
Jim Laskey14edc932006-03-14 18:08:46 +0000341
Devang Patel59445db2010-03-09 00:44:10 +0000342</div>
343
344<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000345<h4>
Devang Patel59445db2010-03-09 00:44:10 +0000346 <a name="format_files">File descriptors</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000347</h4>
Devang Patel59445db2010-03-09 00:44:10 +0000348
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000349<div>
Devang Patel59445db2010-03-09 00:44:10 +0000350
351<div class="doc_code">
352<pre>
353!0 = metadata !{
354 i32, ;; Tag = 41 + <a href="#LLVMDebugVersion">LLVMDebugVersion</a>
355 ;; (DW_TAG_file_type)
356 metadata, ;; Source file name
357 metadata, ;; Source file directory (includes trailing slash)
Devang Pateleb1bb4e2011-08-16 22:09:43 +0000358 metadata ;; Unused
Devang Patel59445db2010-03-09 00:44:10 +0000359}
360</pre>
361</div>
362
John Criswell2a4b0802010-03-17 15:01:50 +0000363<p>These descriptors contain information for a file. Global variables and top
Devang Patel59445db2010-03-09 00:44:10 +0000364 level functions would be defined using this context.k File descriptors also
365 provide context for source line correspondence. </p>
366
367<p>Each input file is encoded as a separate file descriptor in LLVM debugging
Devang Pateleb1bb4e2011-08-16 22:09:43 +0000368 information output. </p>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000369
Jim Laskey14edc932006-03-14 18:08:46 +0000370</div>
371
372<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000373<h4>
Jim Laskey14edc932006-03-14 18:08:46 +0000374 <a name="format_global_variables">Global variable descriptors</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000375</h4>
Jim Laskey14edc932006-03-14 18:08:46 +0000376
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000377<div>
Jim Laskey14edc932006-03-14 18:08:46 +0000378
Bill Wendlinge9353d72009-05-17 05:52:39 +0000379<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000380<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000381!1 = metadata !{
382 i32, ;; Tag = 52 + <a href="#LLVMDebugVersion">LLVMDebugVersion</a>
383 ;; (DW_TAG_variable)
384 i32, ;; Unused field.
385 metadata, ;; Reference to context descriptor
386 metadata, ;; Name
387 metadata, ;; Display name (fully qualified C++ name)
388 metadata, ;; MIPS linkage name (for C++)
Devang Patel59445db2010-03-09 00:44:10 +0000389 metadata, ;; Reference to file where defined
Devang Patel80ae3492009-08-28 23:24:31 +0000390 i32, ;; Line number where defined
391 metadata, ;; Reference to type descriptor
392 i1, ;; True if the global is local to compile unit (static)
393 i1, ;; True if the global is defined in the compile unit (not extern)
Dan Gohmanaabfdb32010-05-28 17:13:49 +0000394 {}* ;; Reference to the global variable
Bill Wendlinge9353d72009-05-17 05:52:39 +0000395}
Jim Laskey14edc932006-03-14 18:08:46 +0000396</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000397</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000398
399<p>These descriptors provide debug information about globals variables. The
Devang Patel1c6b6812011-03-29 17:27:08 +0000400provide details such as name, type and where the variable is defined. All
401global variables are collected by named metadata <tt>!llvm.dbg.gv</tt>.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000402
403</div>
404
405<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000406<h4>
Jim Laskey14edc932006-03-14 18:08:46 +0000407 <a name="format_subprograms">Subprogram descriptors</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000408</h4>
Jim Laskey14edc932006-03-14 18:08:46 +0000409
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000410<div>
Jim Laskey14edc932006-03-14 18:08:46 +0000411
Bill Wendlinge9353d72009-05-17 05:52:39 +0000412<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000413<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000414!2 = metadata !{
415 i32, ;; Tag = 46 + <a href="#LLVMDebugVersion">LLVMDebugVersion</a>
416 ;; (DW_TAG_subprogram)
417 i32, ;; Unused field.
418 metadata, ;; Reference to context descriptor
419 metadata, ;; Name
420 metadata, ;; Display name (fully qualified C++ name)
421 metadata, ;; MIPS linkage name (for C++)
Devang Patel59445db2010-03-09 00:44:10 +0000422 metadata, ;; Reference to file where defined
Devang Patel80ae3492009-08-28 23:24:31 +0000423 i32, ;; Line number where defined
424 metadata, ;; Reference to type descriptor
425 i1, ;; True if the global is local to compile unit (static)
Devang Patel1d6bbd42011-04-22 23:10:17 +0000426 i1, ;; True if the global is defined in the compile unit (not extern)
427 i32, ;; Virtuality, e.g. dwarf::DW_VIRTUALITY__virtual
428 i32, ;; Index into a virtual function
Devang Patele89b7592010-06-04 22:49:55 +0000429 metadata, ;; indicates which base type contains the vtable pointer for the
430 ;; derived class
Devang Patel1d6bbd42011-04-22 23:10:17 +0000431 i1, ;; isArtificial
432 i1, ;; isOptimized
433 Function *,;; Pointer to LLVM function
434 metadata, ;; Lists function template parameters
435 metadata ;; Function declaration descriptor
Devang Patel59e27c52011-08-19 23:28:12 +0000436 metadata ;; List of function variables
Bill Wendlinge9353d72009-05-17 05:52:39 +0000437}
Jim Laskey14edc932006-03-14 18:08:46 +0000438</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000439</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000440
441<p>These descriptors provide debug information about functions, methods and
Bill Wendlinge9353d72009-05-17 05:52:39 +0000442 subprograms. They provide details such as name, return types and the source
Devang Patel1c6b6812011-03-29 17:27:08 +0000443 location where the subprogram is defined.
444 All subprogram descriptors are collected by a named metadata
445 <tt>!llvm.dbg.sp</tt>.
446</p>
Jim Laskey9dcffe72006-03-15 19:10:52 +0000447
448</div>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000449
Jim Laskey9dcffe72006-03-15 19:10:52 +0000450<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000451<h4>
Jim Laskey9dcffe72006-03-15 19:10:52 +0000452 <a name="format_blocks">Block descriptors</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000453</h4>
Jim Laskey9dcffe72006-03-15 19:10:52 +0000454
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000455<div>
Jim Laskey9dcffe72006-03-15 19:10:52 +0000456
Bill Wendlinge9353d72009-05-17 05:52:39 +0000457<div class="doc_code">
Jim Laskey9dcffe72006-03-15 19:10:52 +0000458<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000459!3 = metadata !{
Devang Patel9fbc6802010-10-04 16:51:59 +0000460 i32, ;; Tag = 11 + <a href="#LLVMDebugVersion">LLVMDebugVersion</a> (DW_TAG_lexical_block)
Devang Patelcac38902010-10-01 22:45:00 +0000461 metadata,;; Reference to context descriptor
462 i32, ;; Line number
Devang Patelfb30b852011-03-08 16:25:29 +0000463 i32, ;; Column number
464 metadata,;; Reference to source file
465 i32 ;; Unique ID to identify blocks from a template function
Bill Wendlinge9353d72009-05-17 05:52:39 +0000466}
Jim Laskey9dcffe72006-03-15 19:10:52 +0000467</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000468</div>
Jim Laskey9dcffe72006-03-15 19:10:52 +0000469
470<p>These descriptors provide debug information about nested blocks within a
Devang Patelcac38902010-10-01 22:45:00 +0000471 subprogram. The line number and column numbers are used to dinstinguish
472 two lexical blocks at same depth. </p>
Jim Laskey9dcffe72006-03-15 19:10:52 +0000473
Jim Laskey14edc932006-03-14 18:08:46 +0000474</div>
475
476<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000477<h4>
Jim Laskey14edc932006-03-14 18:08:46 +0000478 <a name="format_basic_type">Basic type descriptors</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000479</h4>
Jim Laskey14edc932006-03-14 18:08:46 +0000480
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000481<div>
Jim Laskey14edc932006-03-14 18:08:46 +0000482
Bill Wendlinge9353d72009-05-17 05:52:39 +0000483<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000484<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000485!4 = metadata !{
486 i32, ;; Tag = 36 + <a href="#LLVMDebugVersion">LLVMDebugVersion</a>
487 ;; (DW_TAG_base_type)
Devang Pateleb1bb4e2011-08-16 22:09:43 +0000488 metadata, ;; Reference to context
Devang Patel80ae3492009-08-28 23:24:31 +0000489 metadata, ;; Name (may be "" for anonymous types)
Devang Patel59445db2010-03-09 00:44:10 +0000490 metadata, ;; Reference to file where defined (may be NULL)
Devang Patel80ae3492009-08-28 23:24:31 +0000491 i32, ;; Line number where defined (may be 0)
492 i64, ;; Size in bits
493 i64, ;; Alignment in bits
494 i64, ;; Offset in bits
495 i32, ;; Flags
496 i32 ;; DWARF type encoding
Bill Wendlinge9353d72009-05-17 05:52:39 +0000497}
Jim Laskey14edc932006-03-14 18:08:46 +0000498</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000499</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000500
501<p>These descriptors define primitive types used in the code. Example int, bool
Bill Wendlinge9353d72009-05-17 05:52:39 +0000502 and float. The context provides the scope of the type, which is usually the
Devang Pateleb1bb4e2011-08-16 22:09:43 +0000503 top level. Since basic types are not usually user defined the context
Bill Wendlinge9353d72009-05-17 05:52:39 +0000504 and line number can be left as NULL and 0. The size, alignment and offset
505 are expressed in bits and can be 64 bit values. The alignment is used to
506 round the offset when embedded in a
507 <a href="#format_composite_type">composite type</a> (example to keep float
508 doubles on 64 bit boundaries.) The offset is the bit offset if embedded in
509 a <a href="#format_composite_type">composite type</a>.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000510
511<p>The type encoding provides the details of the type. The values are typically
Bill Wendlinge9353d72009-05-17 05:52:39 +0000512 one of the following:</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000513
Bill Wendlinge9353d72009-05-17 05:52:39 +0000514<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000515<pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000516DW_ATE_address = 1
517DW_ATE_boolean = 2
518DW_ATE_float = 4
519DW_ATE_signed = 5
520DW_ATE_signed_char = 6
521DW_ATE_unsigned = 7
522DW_ATE_unsigned_char = 8
Jim Laskey14edc932006-03-14 18:08:46 +0000523</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000524</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000525
526</div>
527
528<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000529<h4>
Jim Laskey14edc932006-03-14 18:08:46 +0000530 <a name="format_derived_type">Derived type descriptors</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000531</h4>
Jim Laskey14edc932006-03-14 18:08:46 +0000532
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000533<div>
Jim Laskey14edc932006-03-14 18:08:46 +0000534
Bill Wendlinge9353d72009-05-17 05:52:39 +0000535<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000536<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000537!5 = metadata !{
538 i32, ;; Tag (see below)
539 metadata, ;; Reference to context
540 metadata, ;; Name (may be "" for anonymous types)
Devang Patel59445db2010-03-09 00:44:10 +0000541 metadata, ;; Reference to file where defined (may be NULL)
Devang Patel80ae3492009-08-28 23:24:31 +0000542 i32, ;; Line number where defined (may be 0)
Devang Patelbed5e7d2010-10-01 19:19:30 +0000543 i64, ;; Size in bits
544 i64, ;; Alignment in bits
545 i64, ;; Offset in bits
Devang Patel514b4002011-04-16 00:11:51 +0000546 metadata, ;; Reference to type derived from
547 metadata, ;; (optional) Name of the Objective C property assoicated with
548 ;; Objective-C an ivar
549 metadata, ;; (optional) Name of the Objective C property getter selector.
550 metadata, ;; (optional) Name of the Objective C property setter selector.
551 i32 ;; (optional) Objective C property attributes.
Bill Wendlinge9353d72009-05-17 05:52:39 +0000552}
Jim Laskey14edc932006-03-14 18:08:46 +0000553</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000554</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000555
556<p>These descriptors are used to define types derived from other types. The
557value of the tag varies depending on the meaning. The following are possible
Misha Brukman39dcddf2008-12-16 02:54:22 +0000558tag values:</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000559
Bill Wendlinge9353d72009-05-17 05:52:39 +0000560<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000561<pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000562DW_TAG_formal_parameter = 5
563DW_TAG_member = 13
564DW_TAG_pointer_type = 15
565DW_TAG_reference_type = 16
566DW_TAG_typedef = 22
567DW_TAG_const_type = 38
568DW_TAG_volatile_type = 53
569DW_TAG_restrict_type = 55
Jim Laskey14edc932006-03-14 18:08:46 +0000570</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000571</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000572
Bill Wendlinge9353d72009-05-17 05:52:39 +0000573<p><tt>DW_TAG_member</tt> is used to define a member of
574 a <a href="#format_composite_type">composite type</a>
575 or <a href="#format_subprograms">subprogram</a>. The type of the member is
576 the <a href="#format_derived_type">derived
577 type</a>. <tt>DW_TAG_formal_parameter</tt> is used to define a member which
578 is a formal argument of a subprogram.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000579
Bill Wendlinge9353d72009-05-17 05:52:39 +0000580<p><tt>DW_TAG_typedef</tt> is used to provide a name for the derived type.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000581
Bill Wendlinge9353d72009-05-17 05:52:39 +0000582<p><tt>DW_TAG_pointer_type</tt>,<tt>DW_TAG_reference_type</tt>,
583 <tt>DW_TAG_const_type</tt>, <tt>DW_TAG_volatile_type</tt>
584 and <tt>DW_TAG_restrict_type</tt> are used to qualify
585 the <a href="#format_derived_type">derived type</a>. </p>
Jim Laskey14edc932006-03-14 18:08:46 +0000586
587<p><a href="#format_derived_type">Derived type</a> location can be determined
Devang Pateleb1bb4e2011-08-16 22:09:43 +0000588 from the context and line number. The size, alignment and offset are
Bill Wendlinge9353d72009-05-17 05:52:39 +0000589 expressed in bits and can be 64 bit values. The alignment is used to round
590 the offset when embedded in a <a href="#format_composite_type">composite
591 type</a> (example to keep float doubles on 64 bit boundaries.) The offset is
592 the bit offset if embedded in a <a href="#format_composite_type">composite
593 type</a>.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000594
Devang Patel7846c1e2011-02-03 00:22:17 +0000595<p>Note that the <tt>void *</tt> type is expressed as a type derived from NULL.
596</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000597
598</div>
599
600<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000601<h4>
Jim Laskey14edc932006-03-14 18:08:46 +0000602 <a name="format_composite_type">Composite type descriptors</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000603</h4>
Jim Laskey14edc932006-03-14 18:08:46 +0000604
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000605<div>
Jim Laskey14edc932006-03-14 18:08:46 +0000606
Bill Wendlinge9353d72009-05-17 05:52:39 +0000607<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000608<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000609!6 = metadata !{
610 i32, ;; Tag (see below)
611 metadata, ;; Reference to context
612 metadata, ;; Name (may be "" for anonymous types)
Devang Patel59445db2010-03-09 00:44:10 +0000613 metadata, ;; Reference to file where defined (may be NULL)
Devang Patel80ae3492009-08-28 23:24:31 +0000614 i32, ;; Line number where defined (may be 0)
615 i64, ;; Size in bits
616 i64, ;; Alignment in bits
617 i64, ;; Offset in bits
618 i32, ;; Flags
619 metadata, ;; Reference to type derived from
620 metadata, ;; Reference to array of member descriptors
621 i32 ;; Runtime languages
Bill Wendlinge9353d72009-05-17 05:52:39 +0000622}
Jim Laskey14edc932006-03-14 18:08:46 +0000623</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000624</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000625
626<p>These descriptors are used to define types that are composed of 0 or more
627elements. The value of the tag varies depending on the meaning. The following
Misha Brukman39dcddf2008-12-16 02:54:22 +0000628are possible tag values:</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000629
Bill Wendlinge9353d72009-05-17 05:52:39 +0000630<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000631<pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000632DW_TAG_array_type = 1
633DW_TAG_enumeration_type = 4
634DW_TAG_structure_type = 19
635DW_TAG_union_type = 23
636DW_TAG_vector_type = 259
Bruno Cardoso Lopes9d809ca2009-05-29 17:08:57 +0000637DW_TAG_subroutine_type = 21
638DW_TAG_inheritance = 28
Jim Laskey14edc932006-03-14 18:08:46 +0000639</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000640</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000641
Jim Laskey19f964e2006-06-15 20:51:43 +0000642<p>The vector flag indicates that an array type is a native packed vector.</p>
643
Jim Laskeyb2ff2d42006-06-16 13:14:03 +0000644<p>The members of array types (tag = <tt>DW_TAG_array_type</tt>) or vector types
Bill Wendlinge9353d72009-05-17 05:52:39 +0000645 (tag = <tt>DW_TAG_vector_type</tt>) are <a href="#format_subrange">subrange
646 descriptors</a>, each representing the range of subscripts at that level of
647 indexing.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000648
649<p>The members of enumeration types (tag = <tt>DW_TAG_enumeration_type</tt>) are
Bill Wendlinge9353d72009-05-17 05:52:39 +0000650 <a href="#format_enumeration">enumerator descriptors</a>, each representing
Devang Patel1c6b6812011-03-29 17:27:08 +0000651 the definition of enumeration value for the set. All enumeration type
652 descriptors are collected by named metadata <tt>!llvm.dbg.enum</tt>.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000653
654<p>The members of structure (tag = <tt>DW_TAG_structure_type</tt>) or union (tag
Bill Wendlinge9353d72009-05-17 05:52:39 +0000655 = <tt>DW_TAG_union_type</tt>) types are any one of
656 the <a href="#format_basic_type">basic</a>,
657 <a href="#format_derived_type">derived</a>
658 or <a href="#format_composite_type">composite</a> type descriptors, each
659 representing a field member of the structure or union.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000660
Jim Laskey4771cca2006-08-21 21:21:06 +0000661<p>For C++ classes (tag = <tt>DW_TAG_structure_type</tt>), member descriptors
Bill Wendlinge9353d72009-05-17 05:52:39 +0000662 provide information about base classes, static members and member
663 functions. If a member is a <a href="#format_derived_type">derived type
664 descriptor</a> and has a tag of <tt>DW_TAG_inheritance</tt>, then the type
665 represents a base class. If the member of is
666 a <a href="#format_global_variables">global variable descriptor</a> then it
667 represents a static member. And, if the member is
668 a <a href="#format_subprograms">subprogram descriptor</a> then it represents
669 a member function. For static members and member
670 functions, <tt>getName()</tt> returns the members link or the C++ mangled
671 name. <tt>getDisplayName()</tt> the simplied version of the name.</p>
Jim Laskey4771cca2006-08-21 21:21:06 +0000672
Bill Wendlinge9353d72009-05-17 05:52:39 +0000673<p>The first member of subroutine (tag = <tt>DW_TAG_subroutine_type</tt>) type
674 elements is the return type for the subroutine. The remaining elements are
675 the formal arguments to the subroutine.</p>
Jim Laskey4810c262006-06-20 21:13:20 +0000676
Jim Laskey14edc932006-03-14 18:08:46 +0000677<p><a href="#format_composite_type">Composite type</a> location can be
Devang Pateleb1bb4e2011-08-16 22:09:43 +0000678 determined from the context and line number. The size, alignment and
Bill Wendlinge9353d72009-05-17 05:52:39 +0000679 offset are expressed in bits and can be 64 bit values. The alignment is used
680 to round the offset when embedded in
681 a <a href="#format_composite_type">composite type</a> (as an example, to keep
682 float doubles on 64 bit boundaries.) The offset is the bit offset if embedded
683 in a <a href="#format_composite_type">composite type</a>.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000684
685</div>
686
687<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000688<h4>
Jim Laskey14edc932006-03-14 18:08:46 +0000689 <a name="format_subrange">Subrange descriptors</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000690</h4>
Jim Laskey14edc932006-03-14 18:08:46 +0000691
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000692<div>
Jim Laskey14edc932006-03-14 18:08:46 +0000693
Bill Wendlinge9353d72009-05-17 05:52:39 +0000694<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000695<pre>
Devang Patel7846c1e2011-02-03 00:22:17 +0000696!42 = metadata !{
Bill Wendlinge9353d72009-05-17 05:52:39 +0000697 i32, ;; Tag = 33 + <a href="#LLVMDebugVersion">LLVMDebugVersion</a> (DW_TAG_subrange_type)
698 i64, ;; Low value
699 i64 ;; High value
700}
Jim Laskey14edc932006-03-14 18:08:46 +0000701</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000702</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000703
704<p>These descriptors are used to define ranges of array subscripts for an array
Bill Wendlinge9353d72009-05-17 05:52:39 +0000705 <a href="#format_composite_type">composite type</a>. The low value defines
706 the lower bounds typically zero for C/C++. The high value is the upper
707 bounds. Values are 64 bit. High - low + 1 is the size of the array. If low
Devang Patel778947c2011-04-08 23:39:38 +0000708 > high the array bounds are not included in generated debugging information.
709</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000710
711</div>
712
713<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000714<h4>
Jim Laskey14edc932006-03-14 18:08:46 +0000715 <a name="format_enumeration">Enumerator descriptors</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000716</h4>
Jim Laskey14edc932006-03-14 18:08:46 +0000717
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000718<div>
Jim Laskey14edc932006-03-14 18:08:46 +0000719
Bill Wendlinge9353d72009-05-17 05:52:39 +0000720<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000721<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000722!6 = metadata !{
723 i32, ;; Tag = 40 + <a href="#LLVMDebugVersion">LLVMDebugVersion</a>
724 ;; (DW_TAG_enumerator)
725 metadata, ;; Name
726 i64 ;; Value
Bill Wendlinge9353d72009-05-17 05:52:39 +0000727}
Jim Laskey14edc932006-03-14 18:08:46 +0000728</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000729</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000730
Bill Wendlinge9353d72009-05-17 05:52:39 +0000731<p>These descriptors are used to define members of an
732 enumeration <a href="#format_composite_type">composite type</a>, it
733 associates the name to the value.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000734
735</div>
736
737<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000738<h4>
Jim Laskey5dcfd562006-03-23 17:54:33 +0000739 <a name="format_variables">Local variables</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000740</h4>
Jim Laskey5dcfd562006-03-23 17:54:33 +0000741
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000742<div>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000743
744<div class="doc_code">
Jim Laskey5dcfd562006-03-23 17:54:33 +0000745<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000746!7 = metadata !{
747 i32, ;; Tag (see below)
748 metadata, ;; Context
749 metadata, ;; Name
Devang Patel59445db2010-03-09 00:44:10 +0000750 metadata, ;; Reference to file where defined
Devang Patele1aa67c2011-03-08 16:29:40 +0000751 i32, ;; 24 bit - Line number where defined
752 ;; 8 bit - Argument number. 1 indicates 1st argument.
Devang Patelac0a1f62011-07-27 18:14:50 +0000753 metadata, ;; Type descriptor
754 i32, ;; flags
755 metadata ;; (optional) Reference to inline location
Bill Wendlinge9353d72009-05-17 05:52:39 +0000756}
Jim Laskey5dcfd562006-03-23 17:54:33 +0000757</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000758</div>
Jim Laskey5dcfd562006-03-23 17:54:33 +0000759
760<p>These descriptors are used to define variables local to a sub program. The
Bill Wendlinge9353d72009-05-17 05:52:39 +0000761 value of the tag depends on the usage of the variable:</p>
Jim Laskey5dcfd562006-03-23 17:54:33 +0000762
Bill Wendlinge9353d72009-05-17 05:52:39 +0000763<div class="doc_code">
Jim Laskey5dcfd562006-03-23 17:54:33 +0000764<pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000765DW_TAG_auto_variable = 256
766DW_TAG_arg_variable = 257
767DW_TAG_return_variable = 258
Jim Laskey5dcfd562006-03-23 17:54:33 +0000768</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000769</div>
Jim Laskey5dcfd562006-03-23 17:54:33 +0000770
771<p>An auto variable is any variable declared in the body of the function. An
Bill Wendlinge9353d72009-05-17 05:52:39 +0000772 argument variable is any variable that appears as a formal argument to the
773 function. A return variable is used to track the result of a function and
774 has no source correspondent.</p>
Jim Laskey5dcfd562006-03-23 17:54:33 +0000775
Jim Laskey3481e122006-03-24 09:20:27 +0000776<p>The context is either the subprogram or block where the variable is defined.
Devang Pateleb1bb4e2011-08-16 22:09:43 +0000777 Name the source variable name. Context and line indicate where the
Bill Wendlinge9353d72009-05-17 05:52:39 +0000778 variable was defined. Type descriptor defines the declared type of the
779 variable.</p>
Jim Laskey5dcfd562006-03-23 17:54:33 +0000780
781</div>
782
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000783</div>
784
Jim Laskey5dcfd562006-03-23 17:54:33 +0000785<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000786<h3>
Jim Laskey14edc932006-03-14 18:08:46 +0000787 <a name="format_common_intrinsics">Debugger intrinsic functions</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000788</h3>
Jim Laskey14edc932006-03-14 18:08:46 +0000789
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000790<div>
Jim Laskey14edc932006-03-14 18:08:46 +0000791
792<p>LLVM uses several intrinsic functions (name prefixed with "llvm.dbg") to
Bill Wendlinge9353d72009-05-17 05:52:39 +0000793 provide debug information at various points in generated code.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000794
Jim Laskey14edc932006-03-14 18:08:46 +0000795<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000796<h4>
Jim Laskey14edc932006-03-14 18:08:46 +0000797 <a name="format_common_declare">llvm.dbg.declare</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000798</h4>
Jim Laskey14edc932006-03-14 18:08:46 +0000799
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000800<div>
Jim Laskey14edc932006-03-14 18:08:46 +0000801<pre>
Devang Patel6df452c2010-10-01 19:22:16 +0000802 void %<a href="#format_common_declare">llvm.dbg.declare</a>(metadata, metadata)
Jim Laskey14edc932006-03-14 18:08:46 +0000803</pre>
804
Jim Laskey3481e122006-03-24 09:20:27 +0000805<p>This intrinsic provides information about a local element (ex. variable.) The
NAKAMURA Takumi6bd36d52011-04-09 09:51:57 +0000806 first argument is metadata holding alloca for the variable. The
Devang Patel9a8539c2011-02-01 17:22:12 +0000807 second argument is metadata containing description of the variable. </p>
Jim Laskey14edc932006-03-14 18:08:46 +0000808</div>
809
810<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000811<h4>
Victor Hernandez0b62cc62010-01-11 22:53:48 +0000812 <a name="format_common_value">llvm.dbg.value</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000813</h4>
Victor Hernandez0b62cc62010-01-11 22:53:48 +0000814
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000815<div>
Victor Hernandez0b62cc62010-01-11 22:53:48 +0000816<pre>
Dan Gohmand6a6f612010-05-28 17:07:41 +0000817 void %<a href="#format_common_value">llvm.dbg.value</a>(metadata, i64, metadata)
Victor Hernandez0b62cc62010-01-11 22:53:48 +0000818</pre>
819
820<p>This intrinsic provides information when a user source variable is set to a
821 new value. The first argument is the new value (wrapped as metadata). The
822 second argument is the offset in the user source variable where the new value
Devang Patel9a8539c2011-02-01 17:22:12 +0000823 is written. The third argument is metadata containing description of the
824 user source variable. </p>
Victor Hernandez0b62cc62010-01-11 22:53:48 +0000825</div>
826
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000827</div>
828
Victor Hernandez0b62cc62010-01-11 22:53:48 +0000829<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000830<h3>
Chris Lattner941515c2004-01-06 05:31:32 +0000831 <a name="format_common_lifetime">Object lifetimes and scoping</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000832</h3>
Chris Lattner1811fca2004-01-05 05:06:33 +0000833
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000834<div>
Bill Wendling991b84e2009-12-01 00:53:11 +0000835<p>In many languages, the local variables in functions can have their lifetimes
836 or scopes limited to a subset of a function. In the C family of languages,
Bill Wendlinge9353d72009-05-17 05:52:39 +0000837 for example, variables are only live (readable and writable) within the
838 source block that they are defined in. In functional languages, values are
839 only readable after they have been defined. Though this is a very obvious
Bill Wendling991b84e2009-12-01 00:53:11 +0000840 concept, it is non-trivial to model in LLVM, because it has no notion of
Bill Wendlinge9353d72009-05-17 05:52:39 +0000841 scoping in this sense, and does not want to be tied to a language's scoping
842 rules.</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000843
Bill Wendling991b84e2009-12-01 00:53:11 +0000844<p>In order to handle this, the LLVM debug format uses the metadata attached to
Nick Lewyckya87014f2010-03-31 07:50:17 +0000845 llvm instructions to encode line number and scoping information. Consider
846 the following C fragment, for example:</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000847
Bill Wendlinge9353d72009-05-17 05:52:39 +0000848<div class="doc_code">
Misha Brukmanf91d9942004-05-12 19:21:57 +0000849<pre>
Chris Lattner1811fca2004-01-05 05:06:33 +00008501. void foo() {
Devang Patel4da997b2009-11-25 23:28:01 +00008512. int X = 21;
8523. int Y = 22;
Chris Lattner1811fca2004-01-05 05:06:33 +00008534. {
Devang Patel4da997b2009-11-25 23:28:01 +00008545. int Z = 23;
8556. Z = X;
Chris Lattner1811fca2004-01-05 05:06:33 +00008567. }
Devang Patel4da997b2009-11-25 23:28:01 +00008578. X = Y;
Chris Lattner1811fca2004-01-05 05:06:33 +00008589. }
Misha Brukmanf91d9942004-05-12 19:21:57 +0000859</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000860</div>
Chris Lattner1811fca2004-01-05 05:06:33 +0000861
Jim Laskey14edc932006-03-14 18:08:46 +0000862<p>Compiled to LLVM, this function would be represented like this:</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000863
Bill Wendlinge9353d72009-05-17 05:52:39 +0000864<div class="doc_code">
Misha Brukmanf91d9942004-05-12 19:21:57 +0000865<pre>
Bill Wendling991b84e2009-12-01 00:53:11 +0000866define void @foo() nounwind ssp {
Jim Laskey14edc932006-03-14 18:08:46 +0000867entry:
Bill Wendling05252352009-12-01 00:59:58 +0000868 %X = alloca i32, align 4 ; &lt;i32*&gt; [#uses=4]
869 %Y = alloca i32, align 4 ; &lt;i32*&gt; [#uses=4]
870 %Z = alloca i32, align 4 ; &lt;i32*&gt; [#uses=3]
Dan Gohmanaabfdb32010-05-28 17:13:49 +0000871 %0 = bitcast i32* %X to {}* ; &lt;{}*&gt; [#uses=1]
Devang Patel7846c1e2011-02-03 00:22:17 +0000872 call void @llvm.dbg.declare(metadata !{i32 * %X}, metadata !0), !dbg !7
Devang Patel4da997b2009-11-25 23:28:01 +0000873 store i32 21, i32* %X, !dbg !8
Dan Gohmanaabfdb32010-05-28 17:13:49 +0000874 %1 = bitcast i32* %Y to {}* ; &lt;{}*&gt; [#uses=1]
Devang Patel7846c1e2011-02-03 00:22:17 +0000875 call void @llvm.dbg.declare(metadata !{i32 * %Y}, metadata !9), !dbg !10
Devang Patel4da997b2009-11-25 23:28:01 +0000876 store i32 22, i32* %Y, !dbg !11
Dan Gohmanaabfdb32010-05-28 17:13:49 +0000877 %2 = bitcast i32* %Z to {}* ; &lt;{}*&gt; [#uses=1]
Devang Patel7846c1e2011-02-03 00:22:17 +0000878 call void @llvm.dbg.declare(metadata !{i32 * %Z}, metadata !12), !dbg !14
Devang Patel4da997b2009-11-25 23:28:01 +0000879 store i32 23, i32* %Z, !dbg !15
Bill Wendling05252352009-12-01 00:59:58 +0000880 %tmp = load i32* %X, !dbg !16 ; &lt;i32&gt; [#uses=1]
881 %tmp1 = load i32* %Y, !dbg !16 ; &lt;i32&gt; [#uses=1]
882 %add = add nsw i32 %tmp, %tmp1, !dbg !16 ; &lt;i32&gt; [#uses=1]
Devang Patel4da997b2009-11-25 23:28:01 +0000883 store i32 %add, i32* %Z, !dbg !16
Bill Wendling05252352009-12-01 00:59:58 +0000884 %tmp2 = load i32* %Y, !dbg !17 ; &lt;i32&gt; [#uses=1]
Devang Patel4da997b2009-11-25 23:28:01 +0000885 store i32 %tmp2, i32* %X, !dbg !17
886 ret void, !dbg !18
Chris Lattner1811fca2004-01-05 05:06:33 +0000887}
Devang Patel4da997b2009-11-25 23:28:01 +0000888
Devang Patel7846c1e2011-02-03 00:22:17 +0000889declare void @llvm.dbg.declare(metadata, metadata) nounwind readnone
Devang Patel4da997b2009-11-25 23:28:01 +0000890
891!0 = metadata !{i32 459008, metadata !1, metadata !"X",
892 metadata !3, i32 2, metadata !6}; [ DW_TAG_auto_variable ]
893!1 = metadata !{i32 458763, metadata !2}; [DW_TAG_lexical_block ]
894!2 = metadata !{i32 458798, i32 0, metadata !3, metadata !"foo", metadata !"foo",
895 metadata !"foo", metadata !3, i32 1, metadata !4,
896 i1 false, i1 true}; [DW_TAG_subprogram ]
897!3 = metadata !{i32 458769, i32 0, i32 12, metadata !"foo.c",
898 metadata !"/private/tmp", metadata !"clang 1.1", i1 true,
899 i1 false, metadata !"", i32 0}; [DW_TAG_compile_unit ]
900!4 = metadata !{i32 458773, metadata !3, metadata !"", null, i32 0, i64 0, i64 0,
901 i64 0, i32 0, null, metadata !5, i32 0}; [DW_TAG_subroutine_type ]
902!5 = metadata !{null}
903!6 = metadata !{i32 458788, metadata !3, metadata !"int", metadata !3, i32 0,
904 i64 32, i64 32, i64 0, i32 0, i32 5}; [DW_TAG_base_type ]
905!7 = metadata !{i32 2, i32 7, metadata !1, null}
906!8 = metadata !{i32 2, i32 3, metadata !1, null}
907!9 = metadata !{i32 459008, metadata !1, metadata !"Y", metadata !3, i32 3,
908 metadata !6}; [ DW_TAG_auto_variable ]
909!10 = metadata !{i32 3, i32 7, metadata !1, null}
910!11 = metadata !{i32 3, i32 3, metadata !1, null}
911!12 = metadata !{i32 459008, metadata !13, metadata !"Z", metadata !3, i32 5,
912 metadata !6}; [ DW_TAG_auto_variable ]
913!13 = metadata !{i32 458763, metadata !1}; [DW_TAG_lexical_block ]
914!14 = metadata !{i32 5, i32 9, metadata !13, null}
915!15 = metadata !{i32 5, i32 5, metadata !13, null}
916!16 = metadata !{i32 6, i32 5, metadata !13, null}
917!17 = metadata !{i32 8, i32 3, metadata !1, null}
918!18 = metadata !{i32 9, i32 1, metadata !2, null}
Misha Brukmanf91d9942004-05-12 19:21:57 +0000919</pre>
Chris Lattner1811fca2004-01-05 05:06:33 +0000920</div>
921
Bill Wendling991b84e2009-12-01 00:53:11 +0000922<p>This example illustrates a few important details about LLVM debugging
923 information. In particular, it shows how the <tt>llvm.dbg.declare</tt>
924 intrinsic and location information, which are attached to an instruction,
925 are applied together to allow a debugger to analyze the relationship between
926 statements, variable definitions, and the code used to implement the
927 function.</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000928
Bill Wendling991b84e2009-12-01 00:53:11 +0000929<div class="doc_code">
Bill Wendling05252352009-12-01 00:59:58 +0000930<pre>
Devang Patel7846c1e2011-02-03 00:22:17 +0000931call void @llvm.dbg.declare(metadata, metadata !0), !dbg !7
Bill Wendling991b84e2009-12-01 00:53:11 +0000932</pre>
933</div>
934
935<p>The first intrinsic
Devang Patel4da997b2009-11-25 23:28:01 +0000936 <tt>%<a href="#format_common_declare">llvm.dbg.declare</a></tt>
Bill Wendling991b84e2009-12-01 00:53:11 +0000937 encodes debugging information for the variable <tt>X</tt>. The metadata
938 <tt>!dbg !7</tt> attached to the intrinsic provides scope information for the
939 variable <tt>X</tt>.</p>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000940
Bill Wendling991b84e2009-12-01 00:53:11 +0000941<div class="doc_code">
942<pre>
943!7 = metadata !{i32 2, i32 7, metadata !1, null}
944!1 = metadata !{i32 458763, metadata !2}; [DW_TAG_lexical_block ]
945!2 = metadata !{i32 458798, i32 0, metadata !3, metadata !"foo",
946 metadata !"foo", metadata !"foo", metadata !3, i32 1,
947 metadata !4, i1 false, i1 true}; [DW_TAG_subprogram ]
948</pre>
949</div>
950
951<p>Here <tt>!7</tt> is metadata providing location information. It has four
952 fields: line number, column number, scope, and original scope. The original
953 scope represents inline location if this instruction is inlined inside a
954 caller, and is null otherwise. In this example, scope is encoded by
Devang Patel4da997b2009-11-25 23:28:01 +0000955 <tt>!1</tt>. <tt>!1</tt> represents a lexical block inside the scope
956 <tt>!2</tt>, where <tt>!2</tt> is a
Bill Wendling991b84e2009-12-01 00:53:11 +0000957 <a href="#format_subprograms">subprogram descriptor</a>. This way the
958 location information attached to the intrinsics indicates that the
959 variable <tt>X</tt> is declared at line number 2 at a function level scope in
960 function <tt>foo</tt>.</p>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000961
Devang Patel4da997b2009-11-25 23:28:01 +0000962<p>Now lets take another example.</p>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000963
Bill Wendling991b84e2009-12-01 00:53:11 +0000964<div class="doc_code">
Bill Wendling05252352009-12-01 00:59:58 +0000965<pre>
Devang Patel7846c1e2011-02-03 00:22:17 +0000966call void @llvm.dbg.declare(metadata, metadata !12), !dbg !14
Bill Wendling991b84e2009-12-01 00:53:11 +0000967</pre>
968</div>
969
970<p>The second intrinsic
Devang Patel4da997b2009-11-25 23:28:01 +0000971 <tt>%<a href="#format_common_declare">llvm.dbg.declare</a></tt>
Bill Wendling991b84e2009-12-01 00:53:11 +0000972 encodes debugging information for variable <tt>Z</tt>. The metadata
973 <tt>!dbg !14</tt> attached to the intrinsic provides scope information for
974 the variable <tt>Z</tt>.</p>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000975
Bill Wendling991b84e2009-12-01 00:53:11 +0000976<div class="doc_code">
977<pre>
978!13 = metadata !{i32 458763, metadata !1}; [DW_TAG_lexical_block ]
979!14 = metadata !{i32 5, i32 9, metadata !13, null}
980</pre>
981</div>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000982
John Criswell2a4b0802010-03-17 15:01:50 +0000983<p>Here <tt>!14</tt> indicates that <tt>Z</tt> is declared at line number 5 and
Bill Wendling991b84e2009-12-01 00:53:11 +0000984 column number 9 inside of lexical scope <tt>!13</tt>. The lexical scope
985 itself resides inside of lexical scope <tt>!1</tt> described above.</p>
986
987<p>The scope information attached with each instruction provides a
988 straightforward way to find instructions covered by a scope.</p>
989
Bill Wendlinge9353d72009-05-17 05:52:39 +0000990</div>
Chris Lattner1811fca2004-01-05 05:06:33 +0000991
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +0000992</div>
993
Chris Lattner1811fca2004-01-05 05:06:33 +0000994<!-- *********************************************************************** -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000995<h2>
Chris Lattner941515c2004-01-06 05:31:32 +0000996 <a name="ccxx_frontend">C/C++ front-end specific debug information</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +0000997</h2>
Misha Brukmancda6a9b2004-12-09 20:27:37 +0000998<!-- *********************************************************************** -->
Chris Lattner1811fca2004-01-05 05:06:33 +0000999
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +00001000<div>
Chris Lattner1811fca2004-01-05 05:06:33 +00001001
Misha Brukmanf91d9942004-05-12 19:21:57 +00001002<p>The C and C++ front-ends represent information about the program in a format
Bill Wendlinge9353d72009-05-17 05:52:39 +00001003 that is effectively identical
1004 to <a href="http://www.eagercon.com/dwarf/dwarf3std.htm">DWARF 3.0</a> in
1005 terms of information content. This allows code generators to trivially
1006 support native debuggers by generating standard dwarf information, and
1007 contains enough information for non-dwarf targets to translate it as
1008 needed.</p>
Chris Lattner1811fca2004-01-05 05:06:33 +00001009
Jim Laskey14edc932006-03-14 18:08:46 +00001010<p>This section describes the forms used to represent C and C++ programs. Other
Bill Wendlinge9353d72009-05-17 05:52:39 +00001011 languages could pattern themselves after this (which itself is tuned to
1012 representing programs in the same way that DWARF 3 does), or they could
1013 choose to provide completely different forms if they don't fit into the DWARF
1014 model. As support for debugging information gets added to the various LLVM
1015 source-language front-ends, the information used should be documented
1016 here.</p>
Chris Lattner1811fca2004-01-05 05:06:33 +00001017
Jim Laskey14edc932006-03-14 18:08:46 +00001018<p>The following sections provide examples of various C/C++ constructs and the
Bill Wendlinge9353d72009-05-17 05:52:39 +00001019 debug information that would best describe those constructs.</p>
Jim Laskey14edc932006-03-14 18:08:46 +00001020
Chris Lattner1811fca2004-01-05 05:06:33 +00001021<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001022<h3>
Jim Laskey14edc932006-03-14 18:08:46 +00001023 <a name="ccxx_compile_units">C/C++ source file information</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001024</h3>
Chris Lattner1811fca2004-01-05 05:06:33 +00001025
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +00001026<div>
Chris Lattner1811fca2004-01-05 05:06:33 +00001027
Bill Wendlinge9353d72009-05-17 05:52:39 +00001028<p>Given the source files <tt>MySource.cpp</tt> and <tt>MyHeader.h</tt> located
1029 in the directory <tt>/Users/mine/sources</tt>, the following code:</p>
Chris Lattner941515c2004-01-06 05:31:32 +00001030
Bill Wendlinge9353d72009-05-17 05:52:39 +00001031<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001032<pre>
1033#include "MyHeader.h"
Chris Lattner941515c2004-01-06 05:31:32 +00001034
Jim Laskey14edc932006-03-14 18:08:46 +00001035int main(int argc, char *argv[]) {
1036 return 0;
1037}
1038</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001039</div>
Chris Lattner941515c2004-01-06 05:31:32 +00001040
Misha Brukman39dcddf2008-12-16 02:54:22 +00001041<p>a C/C++ front-end would generate the following descriptors:</p>
Jim Laskey14edc932006-03-14 18:08:46 +00001042
Bill Wendlinge9353d72009-05-17 05:52:39 +00001043<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001044<pre>
1045...
1046;;
Devang Patel59445db2010-03-09 00:44:10 +00001047;; Define the compile unit for the main source file "/Users/mine/sources/MySource.cpp".
Jim Laskey14edc932006-03-14 18:08:46 +00001048;;
Devang Patel59445db2010-03-09 00:44:10 +00001049!2 = metadata !{
1050 i32 524305, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001051 i32 0, ;; Unused
1052 i32 4, ;; Language Id
1053 metadata !"MySource.cpp",
1054 metadata !"/Users/mine/sources",
1055 metadata !"4.2.1 (Based on Apple Inc. build 5649) (LLVM build 00)",
1056 i1 true, ;; Main Compile Unit
1057 i1 false, ;; Optimized compile unit
1058 metadata !"", ;; Compiler flags
1059 i32 0} ;; Runtime version
1060
Jim Laskey14edc932006-03-14 18:08:46 +00001061;;
Devang Patel59445db2010-03-09 00:44:10 +00001062;; Define the file for the file "/Users/mine/sources/MySource.cpp".
Jim Laskey14edc932006-03-14 18:08:46 +00001063;;
Devang Patel80ae3492009-08-28 23:24:31 +00001064!1 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001065 i32 524329, ;; Tag
1066 metadata !"MySource.cpp",
Devang Patel80ae3492009-08-28 23:24:31 +00001067 metadata !"/Users/mine/sources",
Devang Patel4a7904d62010-07-13 16:53:20 +00001068 metadata !2 ;; Compile unit
Devang Patel59445db2010-03-09 00:44:10 +00001069}
1070
1071;;
1072;; Define the file for the file "/Users/mine/sources/Myheader.h"
1073;;
1074!3 = metadata !{
1075 i32 524329, ;; Tag
1076 metadata !"Myheader.h"
1077 metadata !"/Users/mine/sources",
Devang Patel4a7904d62010-07-13 16:53:20 +00001078 metadata !2 ;; Compile unit
Devang Patel59445db2010-03-09 00:44:10 +00001079}
Jim Laskey14edc932006-03-14 18:08:46 +00001080
Jim Laskey14edc932006-03-14 18:08:46 +00001081...
1082</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001083</div>
Jim Laskey14edc932006-03-14 18:08:46 +00001084
Devang Patel5bc1c4b2010-03-26 19:08:36 +00001085<p>llvm::Instruction provides easy access to metadata attached with an
1086instruction. One can extract line number information encoded in LLVM IR
1087using <tt>Instruction::getMetadata()</tt> and
1088<tt>DILocation::getLineNumber()</tt>.
1089<pre>
1090 if (MDNode *N = I->getMetadata("dbg")) { // Here I is an LLVM instruction
1091 DILocation Loc(N); // DILocation is in DebugInfo.h
1092 unsigned Line = Loc.getLineNumber();
1093 StringRef File = Loc.getFilename();
1094 StringRef Dir = Loc.getDirectory();
1095 }
1096</pre>
Chris Lattner941515c2004-01-06 05:31:32 +00001097</div>
1098
1099<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001100<h3>
Jim Laskey14edc932006-03-14 18:08:46 +00001101 <a name="ccxx_global_variable">C/C++ global variable information</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001102</h3>
Chris Lattner941515c2004-01-06 05:31:32 +00001103
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +00001104<div>
Jim Laskey14edc932006-03-14 18:08:46 +00001105
Misha Brukman39dcddf2008-12-16 02:54:22 +00001106<p>Given an integer global variable declared as follows:</p>
Jim Laskey14edc932006-03-14 18:08:46 +00001107
Bill Wendlinge9353d72009-05-17 05:52:39 +00001108<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001109<pre>
1110int MyGlobal = 100;
1111</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001112</div>
Jim Laskey14edc932006-03-14 18:08:46 +00001113
Misha Brukman39dcddf2008-12-16 02:54:22 +00001114<p>a C/C++ front-end would generate the following descriptors:</p>
Jim Laskey14edc932006-03-14 18:08:46 +00001115
Bill Wendlinge9353d72009-05-17 05:52:39 +00001116<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001117<pre>
1118;;
Jim Laskey14edc932006-03-14 18:08:46 +00001119;; Define the global itself.
1120;;
1121%MyGlobal = global int 100
1122...
1123;;
Devang Patel80ae3492009-08-28 23:24:31 +00001124;; List of debug info of globals
Jim Laskey14edc932006-03-14 18:08:46 +00001125;;
Devang Patel80ae3492009-08-28 23:24:31 +00001126!llvm.dbg.gv = !{!0}
Jim Laskey14edc932006-03-14 18:08:46 +00001127
1128;;
1129;; Define the global variable descriptor. Note the reference to the global
1130;; variable anchor and the global variable itself.
1131;;
Devang Patel80ae3492009-08-28 23:24:31 +00001132!0 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001133 i32 524340, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001134 i32 0, ;; Unused
1135 metadata !1, ;; Context
1136 metadata !"MyGlobal", ;; Name
1137 metadata !"MyGlobal", ;; Display Name
1138 metadata !"MyGlobal", ;; Linkage Name
Devang Patel59445db2010-03-09 00:44:10 +00001139 metadata !3, ;; Compile Unit
Devang Patel80ae3492009-08-28 23:24:31 +00001140 i32 1, ;; Line Number
Devang Patel59445db2010-03-09 00:44:10 +00001141 metadata !4, ;; Type
Devang Patel80ae3492009-08-28 23:24:31 +00001142 i1 false, ;; Is a local variable
1143 i1 true, ;; Is this a definition
1144 i32* @MyGlobal ;; The global variable
1145}
1146
Jim Laskey14edc932006-03-14 18:08:46 +00001147;;
1148;; Define the basic type of 32 bit signed integer. Note that since int is an
1149;; intrinsic type the source file is NULL and line 0.
1150;;
Devang Patel59445db2010-03-09 00:44:10 +00001151!4 = metadata !{
1152 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001153 metadata !1, ;; Context
1154 metadata !"int", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +00001155 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001156 i32 0, ;; Line number
1157 i64 32, ;; Size in Bits
1158 i64 32, ;; Align in Bits
1159 i64 0, ;; Offset in Bits
1160 i32 0, ;; Flags
1161 i32 5 ;; Encoding
1162}
Jim Laskey14edc932006-03-14 18:08:46 +00001163
Jim Laskey14edc932006-03-14 18:08:46 +00001164</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001165</div>
Jim Laskey14edc932006-03-14 18:08:46 +00001166
Chris Lattner941515c2004-01-06 05:31:32 +00001167</div>
Chris Lattner1811fca2004-01-05 05:06:33 +00001168
Jim Laskey14edc932006-03-14 18:08:46 +00001169<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001170<h3>
Jim Laskey14edc932006-03-14 18:08:46 +00001171 <a name="ccxx_subprogram">C/C++ function information</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001172</h3>
Jim Laskey14edc932006-03-14 18:08:46 +00001173
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +00001174<div>
Jim Laskey14edc932006-03-14 18:08:46 +00001175
Misha Brukman39dcddf2008-12-16 02:54:22 +00001176<p>Given a function declared as follows:</p>
Jim Laskey14edc932006-03-14 18:08:46 +00001177
Bill Wendlinge9353d72009-05-17 05:52:39 +00001178<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001179<pre>
1180int main(int argc, char *argv[]) {
1181 return 0;
1182}
1183</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001184</div>
Jim Laskey14edc932006-03-14 18:08:46 +00001185
Misha Brukman39dcddf2008-12-16 02:54:22 +00001186<p>a C/C++ front-end would generate the following descriptors:</p>
Jim Laskey14edc932006-03-14 18:08:46 +00001187
Bill Wendlinge9353d72009-05-17 05:52:39 +00001188<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001189<pre>
1190;;
Jim Laskey14edc932006-03-14 18:08:46 +00001191;; Define the anchor for subprograms. Note that the second field of the
1192;; anchor is 46, which is the same as the tag for subprograms
1193;; (46 = DW_TAG_subprogram.)
1194;;
Devang Patel59445db2010-03-09 00:44:10 +00001195!6 = metadata !{
1196 i32 524334, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001197 i32 0, ;; Unused
1198 metadata !1, ;; Context
1199 metadata !"main", ;; Name
1200 metadata !"main", ;; Display name
1201 metadata !"main", ;; Linkage name
Devang Patel59445db2010-03-09 00:44:10 +00001202 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001203 i32 1, ;; Line number
Devang Patel59445db2010-03-09 00:44:10 +00001204 metadata !4, ;; Type
Devang Patel80ae3492009-08-28 23:24:31 +00001205 i1 false, ;; Is local
Devang Patel9f738842011-04-05 22:52:06 +00001206 i1 true, ;; Is definition
1207 i32 0, ;; Virtuality attribute, e.g. pure virtual function
1208 i32 0, ;; Index into virtual table for C++ methods
1209 i32 0, ;; Type that holds virtual table.
1210 i32 0, ;; Flags
1211 i1 false, ;; True if this function is optimized
1212 Function *, ;; Pointer to llvm::Function
1213 null ;; Function template parameters
Devang Patel80ae3492009-08-28 23:24:31 +00001214}
Jim Laskey14edc932006-03-14 18:08:46 +00001215;;
1216;; Define the subprogram itself.
1217;;
Devang Patel80ae3492009-08-28 23:24:31 +00001218define i32 @main(i32 %argc, i8** %argv) {
Jim Laskey14edc932006-03-14 18:08:46 +00001219...
1220}
1221</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001222</div>
Jim Laskey14edc932006-03-14 18:08:46 +00001223
1224</div>
1225
1226<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001227<h3>
Jim Laskey14edc932006-03-14 18:08:46 +00001228 <a name="ccxx_basic_types">C/C++ basic types</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001229</h3>
Jim Laskey14edc932006-03-14 18:08:46 +00001230
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +00001231<div>
Jim Laskey14edc932006-03-14 18:08:46 +00001232
Misha Brukman39dcddf2008-12-16 02:54:22 +00001233<p>The following are the basic type descriptors for C/C++ core types:</p>
Jim Laskey14edc932006-03-14 18:08:46 +00001234
Jim Laskey14edc932006-03-14 18:08:46 +00001235<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001236<h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001237 <a name="ccxx_basic_type_bool">bool</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001238</h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001239
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +00001240<div>
Jim Laskey14edc932006-03-14 18:08:46 +00001241
Bill Wendlinge9353d72009-05-17 05:52:39 +00001242<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001243<pre>
Devang Patel80ae3492009-08-28 23:24:31 +00001244!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001245 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001246 metadata !1, ;; Context
1247 metadata !"bool", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +00001248 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001249 i32 0, ;; Line number
1250 i64 8, ;; Size in Bits
1251 i64 8, ;; Align in Bits
1252 i64 0, ;; Offset in Bits
1253 i32 0, ;; Flags
1254 i32 2 ;; Encoding
1255}
Jim Laskey14edc932006-03-14 18:08:46 +00001256</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001257</div>
Jim Laskey14edc932006-03-14 18:08:46 +00001258
1259</div>
1260
1261<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001262<h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001263 <a name="ccxx_basic_char">char</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001264</h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001265
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +00001266<div>
Jim Laskey14edc932006-03-14 18:08:46 +00001267
Bill Wendlinge9353d72009-05-17 05:52:39 +00001268<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001269<pre>
Devang Patel80ae3492009-08-28 23:24:31 +00001270!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001271 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001272 metadata !1, ;; Context
1273 metadata !"char", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +00001274 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001275 i32 0, ;; Line number
1276 i64 8, ;; Size in Bits
1277 i64 8, ;; Align in Bits
1278 i64 0, ;; Offset in Bits
1279 i32 0, ;; Flags
1280 i32 6 ;; Encoding
1281}
Jim Laskey14edc932006-03-14 18:08:46 +00001282</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001283</div>
Jim Laskey14edc932006-03-14 18:08:46 +00001284
1285</div>
1286
1287<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001288<h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001289 <a name="ccxx_basic_unsigned_char">unsigned char</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001290</h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001291
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +00001292<div>
Jim Laskey14edc932006-03-14 18:08:46 +00001293
Bill Wendlinge9353d72009-05-17 05:52:39 +00001294<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001295<pre>
Devang Patel80ae3492009-08-28 23:24:31 +00001296!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001297 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001298 metadata !1, ;; Context
1299 metadata !"unsigned char",
Devang Patel59445db2010-03-09 00:44:10 +00001300 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001301 i32 0, ;; Line number
1302 i64 8, ;; Size in Bits
1303 i64 8, ;; Align in Bits
1304 i64 0, ;; Offset in Bits
1305 i32 0, ;; Flags
1306 i32 8 ;; Encoding
1307}
Jim Laskey14edc932006-03-14 18:08:46 +00001308</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001309</div>
Jim Laskey14edc932006-03-14 18:08:46 +00001310
1311</div>
1312
1313<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001314<h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001315 <a name="ccxx_basic_short">short</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001316</h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001317
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +00001318<div>
Jim Laskey14edc932006-03-14 18:08:46 +00001319
Bill Wendlinge9353d72009-05-17 05:52:39 +00001320<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001321<pre>
Devang Patel80ae3492009-08-28 23:24:31 +00001322!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001323 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001324 metadata !1, ;; Context
1325 metadata !"short int",
Devang Patel59445db2010-03-09 00:44:10 +00001326 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001327 i32 0, ;; Line number
1328 i64 16, ;; Size in Bits
1329 i64 16, ;; Align in Bits
1330 i64 0, ;; Offset in Bits
1331 i32 0, ;; Flags
1332 i32 5 ;; Encoding
1333}
Jim Laskey14edc932006-03-14 18:08:46 +00001334</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001335</div>
Jim Laskey14edc932006-03-14 18:08:46 +00001336
1337</div>
1338
1339<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001340<h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001341 <a name="ccxx_basic_unsigned_short">unsigned short</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001342</h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001343
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +00001344<div>
Jim Laskey14edc932006-03-14 18:08:46 +00001345
Bill Wendlinge9353d72009-05-17 05:52:39 +00001346<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001347<pre>
Devang Patel80ae3492009-08-28 23:24:31 +00001348!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001349 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001350 metadata !1, ;; Context
1351 metadata !"short unsigned int",
Devang Patel59445db2010-03-09 00:44:10 +00001352 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001353 i32 0, ;; Line number
1354 i64 16, ;; Size in Bits
1355 i64 16, ;; Align in Bits
1356 i64 0, ;; Offset in Bits
1357 i32 0, ;; Flags
1358 i32 7 ;; Encoding
1359}
Jim Laskey14edc932006-03-14 18:08:46 +00001360</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001361</div>
Jim Laskey14edc932006-03-14 18:08:46 +00001362
1363</div>
1364
1365<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001366<h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001367 <a name="ccxx_basic_int">int</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001368</h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001369
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +00001370<div>
Jim Laskey14edc932006-03-14 18:08:46 +00001371
Bill Wendlinge9353d72009-05-17 05:52:39 +00001372<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001373<pre>
Devang Patel80ae3492009-08-28 23:24:31 +00001374!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001375 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001376 metadata !1, ;; Context
1377 metadata !"int", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +00001378 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001379 i32 0, ;; Line number
1380 i64 32, ;; Size in Bits
1381 i64 32, ;; Align in Bits
1382 i64 0, ;; Offset in Bits
1383 i32 0, ;; Flags
1384 i32 5 ;; Encoding
1385}
Bill Wendlinge9353d72009-05-17 05:52:39 +00001386</pre></div>
Jim Laskey14edc932006-03-14 18:08:46 +00001387
1388</div>
1389
1390<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001391<h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001392 <a name="ccxx_basic_unsigned_int">unsigned int</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001393</h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001394
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +00001395<div>
Jim Laskey14edc932006-03-14 18:08:46 +00001396
Bill Wendlinge9353d72009-05-17 05:52:39 +00001397<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001398<pre>
Devang Patel80ae3492009-08-28 23:24:31 +00001399!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001400 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001401 metadata !1, ;; Context
1402 metadata !"unsigned int",
Devang Patel59445db2010-03-09 00:44:10 +00001403 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001404 i32 0, ;; Line number
1405 i64 32, ;; Size in Bits
1406 i64 32, ;; Align in Bits
1407 i64 0, ;; Offset in Bits
1408 i32 0, ;; Flags
1409 i32 7 ;; Encoding
1410}
Jim Laskey14edc932006-03-14 18:08:46 +00001411</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001412</div>
Jim Laskey14edc932006-03-14 18:08:46 +00001413
1414</div>
1415
1416<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001417<h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001418 <a name="ccxx_basic_long_long">long long</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001419</h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001420
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +00001421<div>
Jim Laskey14edc932006-03-14 18:08:46 +00001422
Bill Wendlinge9353d72009-05-17 05:52:39 +00001423<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001424<pre>
Devang Patel80ae3492009-08-28 23:24:31 +00001425!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001426 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001427 metadata !1, ;; Context
1428 metadata !"long long int",
Devang Patel59445db2010-03-09 00:44:10 +00001429 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001430 i32 0, ;; Line number
1431 i64 64, ;; Size in Bits
1432 i64 64, ;; Align in Bits
1433 i64 0, ;; Offset in Bits
1434 i32 0, ;; Flags
1435 i32 5 ;; Encoding
1436}
Jim Laskey14edc932006-03-14 18:08:46 +00001437</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001438</div>
Jim Laskey14edc932006-03-14 18:08:46 +00001439
1440</div>
1441
1442<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001443<h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001444 <a name="ccxx_basic_unsigned_long_long">unsigned long long</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001445</h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001446
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +00001447<div>
Jim Laskey14edc932006-03-14 18:08:46 +00001448
Bill Wendlinge9353d72009-05-17 05:52:39 +00001449<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001450<pre>
Devang Patel80ae3492009-08-28 23:24:31 +00001451!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001452 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001453 metadata !1, ;; Context
1454 metadata !"long long unsigned int",
Devang Patel59445db2010-03-09 00:44:10 +00001455 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001456 i32 0, ;; Line number
1457 i64 64, ;; Size in Bits
1458 i64 64, ;; Align in Bits
1459 i64 0, ;; Offset in Bits
1460 i32 0, ;; Flags
1461 i32 7 ;; Encoding
1462}
Jim Laskey14edc932006-03-14 18:08:46 +00001463</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001464</div>
Jim Laskey14edc932006-03-14 18:08:46 +00001465
1466</div>
1467
1468<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001469<h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001470 <a name="ccxx_basic_float">float</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001471</h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001472
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +00001473<div>
Jim Laskey14edc932006-03-14 18:08:46 +00001474
Bill Wendlinge9353d72009-05-17 05:52:39 +00001475<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001476<pre>
Devang Patel80ae3492009-08-28 23:24:31 +00001477!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001478 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001479 metadata !1, ;; Context
1480 metadata !"float",
Devang Patel59445db2010-03-09 00:44:10 +00001481 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001482 i32 0, ;; Line number
1483 i64 32, ;; Size in Bits
1484 i64 32, ;; Align in Bits
1485 i64 0, ;; Offset in Bits
1486 i32 0, ;; Flags
1487 i32 4 ;; Encoding
1488}
Jim Laskey14edc932006-03-14 18:08:46 +00001489</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001490</div>
Jim Laskey14edc932006-03-14 18:08:46 +00001491
1492</div>
1493
1494<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001495<h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001496 <a name="ccxx_basic_double">double</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001497</h4>
Jim Laskey14edc932006-03-14 18:08:46 +00001498
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +00001499<div>
Jim Laskey14edc932006-03-14 18:08:46 +00001500
Bill Wendlinge9353d72009-05-17 05:52:39 +00001501<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001502<pre>
Devang Patel80ae3492009-08-28 23:24:31 +00001503!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001504 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001505 metadata !1, ;; Context
1506 metadata !"double",;; Name
Devang Patel59445db2010-03-09 00:44:10 +00001507 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001508 i32 0, ;; Line number
1509 i64 64, ;; Size in Bits
1510 i64 64, ;; Align in Bits
1511 i64 0, ;; Offset in Bits
1512 i32 0, ;; Flags
1513 i32 4 ;; Encoding
1514}
Jim Laskey14edc932006-03-14 18:08:46 +00001515</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001516</div>
Jim Laskey14edc932006-03-14 18:08:46 +00001517
1518</div>
1519
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +00001520</div>
1521
Jim Laskey14edc932006-03-14 18:08:46 +00001522<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001523<h3>
Jim Laskey14edc932006-03-14 18:08:46 +00001524 <a name="ccxx_derived_types">C/C++ derived types</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001525</h3>
Jim Laskey14edc932006-03-14 18:08:46 +00001526
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +00001527<div>
Jim Laskey14edc932006-03-14 18:08:46 +00001528
Misha Brukman39dcddf2008-12-16 02:54:22 +00001529<p>Given the following as an example of C/C++ derived type:</p>
Jim Laskey14edc932006-03-14 18:08:46 +00001530
Bill Wendlinge9353d72009-05-17 05:52:39 +00001531<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001532<pre>
1533typedef const int *IntPtr;
1534</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001535</div>
Jim Laskey14edc932006-03-14 18:08:46 +00001536
Misha Brukman39dcddf2008-12-16 02:54:22 +00001537<p>a C/C++ front-end would generate the following descriptors:</p>
Jim Laskey14edc932006-03-14 18:08:46 +00001538
Bill Wendlinge9353d72009-05-17 05:52:39 +00001539<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001540<pre>
1541;;
1542;; Define the typedef "IntPtr".
1543;;
Devang Patel80ae3492009-08-28 23:24:31 +00001544!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001545 i32 524310, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001546 metadata !1, ;; Context
1547 metadata !"IntPtr", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +00001548 metadata !3, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001549 i32 0, ;; Line number
1550 i64 0, ;; Size in bits
1551 i64 0, ;; Align in bits
1552 i64 0, ;; Offset in bits
1553 i32 0, ;; Flags
1554 metadata !4 ;; Derived From type
1555}
Jim Laskey14edc932006-03-14 18:08:46 +00001556
1557;;
1558;; Define the pointer type.
1559;;
Devang Patel80ae3492009-08-28 23:24:31 +00001560!4 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001561 i32 524303, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001562 metadata !1, ;; Context
1563 metadata !"", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +00001564 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001565 i32 0, ;; Line number
1566 i64 64, ;; Size in bits
1567 i64 64, ;; Align in bits
1568 i64 0, ;; Offset in bits
1569 i32 0, ;; Flags
1570 metadata !5 ;; Derived From type
1571}
Jim Laskey14edc932006-03-14 18:08:46 +00001572;;
1573;; Define the const type.
1574;;
Devang Patel80ae3492009-08-28 23:24:31 +00001575!5 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001576 i32 524326, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001577 metadata !1, ;; Context
1578 metadata !"", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +00001579 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001580 i32 0, ;; Line number
1581 i64 32, ;; Size in bits
1582 i64 32, ;; Align in bits
1583 i64 0, ;; Offset in bits
1584 i32 0, ;; Flags
1585 metadata !6 ;; Derived From type
1586}
Jim Laskey14edc932006-03-14 18:08:46 +00001587;;
1588;; Define the int type.
1589;;
Devang Patel80ae3492009-08-28 23:24:31 +00001590!6 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001591 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001592 metadata !1, ;; Context
1593 metadata !"int", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +00001594 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001595 i32 0, ;; Line number
1596 i64 32, ;; Size in bits
1597 i64 32, ;; Align in bits
1598 i64 0, ;; Offset in bits
1599 i32 0, ;; Flags
1600 5 ;; Encoding
1601}
Jim Laskey14edc932006-03-14 18:08:46 +00001602</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001603</div>
Jim Laskey14edc932006-03-14 18:08:46 +00001604
1605</div>
1606
1607<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001608<h3>
Jim Laskey14edc932006-03-14 18:08:46 +00001609 <a name="ccxx_composite_types">C/C++ struct/union types</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001610</h3>
Jim Laskey14edc932006-03-14 18:08:46 +00001611
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +00001612<div>
Jim Laskey14edc932006-03-14 18:08:46 +00001613
Misha Brukman39dcddf2008-12-16 02:54:22 +00001614<p>Given the following as an example of C/C++ struct type:</p>
Jim Laskey14edc932006-03-14 18:08:46 +00001615
Bill Wendlinge9353d72009-05-17 05:52:39 +00001616<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001617<pre>
1618struct Color {
1619 unsigned Red;
1620 unsigned Green;
1621 unsigned Blue;
1622};
1623</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001624</div>
Jim Laskey14edc932006-03-14 18:08:46 +00001625
Misha Brukman39dcddf2008-12-16 02:54:22 +00001626<p>a C/C++ front-end would generate the following descriptors:</p>
Jim Laskey14edc932006-03-14 18:08:46 +00001627
Bill Wendlinge9353d72009-05-17 05:52:39 +00001628<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001629<pre>
1630;;
1631;; Define basic type for unsigned int.
1632;;
Devang Patel80ae3492009-08-28 23:24:31 +00001633!5 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001634 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001635 metadata !1, ;; Context
1636 metadata !"unsigned int",
Devang Patel59445db2010-03-09 00:44:10 +00001637 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001638 i32 0, ;; Line number
1639 i64 32, ;; Size in Bits
1640 i64 32, ;; Align in Bits
1641 i64 0, ;; Offset in Bits
1642 i32 0, ;; Flags
1643 i32 7 ;; Encoding
1644}
Jim Laskey14edc932006-03-14 18:08:46 +00001645;;
1646;; Define composite type for struct Color.
1647;;
Devang Patel80ae3492009-08-28 23:24:31 +00001648!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001649 i32 524307, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001650 metadata !1, ;; Context
1651 metadata !"Color", ;; Name
1652 metadata !1, ;; Compile unit
1653 i32 1, ;; Line number
1654 i64 96, ;; Size in bits
1655 i64 32, ;; Align in bits
1656 i64 0, ;; Offset in bits
1657 i32 0, ;; Flags
1658 null, ;; Derived From
1659 metadata !3, ;; Elements
1660 i32 0 ;; Runtime Language
1661}
Jim Laskey14edc932006-03-14 18:08:46 +00001662
1663;;
1664;; Define the Red field.
1665;;
Devang Patel80ae3492009-08-28 23:24:31 +00001666!4 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001667 i32 524301, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001668 metadata !1, ;; Context
1669 metadata !"Red", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +00001670 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001671 i32 2, ;; Line number
1672 i64 32, ;; Size in bits
1673 i64 32, ;; Align in bits
1674 i64 0, ;; Offset in bits
1675 i32 0, ;; Flags
1676 metadata !5 ;; Derived From type
1677}
Jim Laskey14edc932006-03-14 18:08:46 +00001678
1679;;
1680;; Define the Green field.
1681;;
Devang Patel80ae3492009-08-28 23:24:31 +00001682!6 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001683 i32 524301, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001684 metadata !1, ;; Context
1685 metadata !"Green", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +00001686 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001687 i32 3, ;; Line number
1688 i64 32, ;; Size in bits
1689 i64 32, ;; Align in bits
1690 i64 32, ;; Offset in bits
1691 i32 0, ;; Flags
1692 metadata !5 ;; Derived From type
1693}
Jim Laskey14edc932006-03-14 18:08:46 +00001694
1695;;
1696;; Define the Blue field.
1697;;
Devang Patel80ae3492009-08-28 23:24:31 +00001698!7 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001699 i32 524301, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001700 metadata !1, ;; Context
1701 metadata !"Blue", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +00001702 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001703 i32 4, ;; Line number
1704 i64 32, ;; Size in bits
1705 i64 32, ;; Align in bits
1706 i64 64, ;; Offset in bits
1707 i32 0, ;; Flags
1708 metadata !5 ;; Derived From type
1709}
Jim Laskey14edc932006-03-14 18:08:46 +00001710
1711;;
1712;; Define the array of fields used by the composite type Color.
1713;;
Devang Patel80ae3492009-08-28 23:24:31 +00001714!3 = metadata !{metadata !4, metadata !6, metadata !7}
Jim Laskey14edc932006-03-14 18:08:46 +00001715</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001716</div>
Jim Laskey14edc932006-03-14 18:08:46 +00001717
1718</div>
1719
1720<!-- ======================================================================= -->
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001721<h3>
Jim Laskey14edc932006-03-14 18:08:46 +00001722 <a name="ccxx_enumeration_types">C/C++ enumeration types</a>
NAKAMURA Takumifc8d9302011-04-18 23:59:50 +00001723</h3>
Jim Laskey14edc932006-03-14 18:08:46 +00001724
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +00001725<div>
Jim Laskey14edc932006-03-14 18:08:46 +00001726
Misha Brukman39dcddf2008-12-16 02:54:22 +00001727<p>Given the following as an example of C/C++ enumeration type:</p>
Jim Laskey14edc932006-03-14 18:08:46 +00001728
Bill Wendlinge9353d72009-05-17 05:52:39 +00001729<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001730<pre>
1731enum Trees {
1732 Spruce = 100,
1733 Oak = 200,
1734 Maple = 300
1735};
1736</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001737</div>
Jim Laskey14edc932006-03-14 18:08:46 +00001738
Misha Brukman39dcddf2008-12-16 02:54:22 +00001739<p>a C/C++ front-end would generate the following descriptors:</p>
Jim Laskey14edc932006-03-14 18:08:46 +00001740
Bill Wendlinge9353d72009-05-17 05:52:39 +00001741<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +00001742<pre>
1743;;
1744;; Define composite type for enum Trees
1745;;
Devang Patel80ae3492009-08-28 23:24:31 +00001746!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +00001747 i32 524292, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +00001748 metadata !1, ;; Context
1749 metadata !"Trees", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +00001750 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +00001751 i32 1, ;; Line number
1752 i64 32, ;; Size in bits
1753 i64 32, ;; Align in bits
1754 i64 0, ;; Offset in bits
1755 i32 0, ;; Flags
1756 null, ;; Derived From type
1757 metadata !3, ;; Elements
1758 i32 0 ;; Runtime language
1759}
Devang Patel02aac922009-08-25 05:24:07 +00001760
Devang Patelf08e35d2009-08-26 05:01:18 +00001761;;
1762;; Define the array of enumerators used by composite type Trees.
1763;;
Devang Patel80ae3492009-08-28 23:24:31 +00001764!3 = metadata !{metadata !4, metadata !5, metadata !6}
1765
1766;;
1767;; Define Spruce enumerator.
1768;;
Devang Patel59445db2010-03-09 00:44:10 +00001769!4 = metadata !{i32 524328, metadata !"Spruce", i64 100}
Devang Patel80ae3492009-08-28 23:24:31 +00001770
1771;;
1772;; Define Oak enumerator.
1773;;
Devang Patel59445db2010-03-09 00:44:10 +00001774!5 = metadata !{i32 524328, metadata !"Oak", i64 200}
Devang Patel80ae3492009-08-28 23:24:31 +00001775
1776;;
1777;; Define Maple enumerator.
1778;;
Devang Patel59445db2010-03-09 00:44:10 +00001779!6 = metadata !{i32 524328, metadata !"Maple", i64 300}
Devang Patel80ae3492009-08-28 23:24:31 +00001780
Jim Laskey14edc932006-03-14 18:08:46 +00001781</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +00001782</div>
Jim Laskey14edc932006-03-14 18:08:46 +00001783
1784</div>
Chris Lattner1811fca2004-01-05 05:06:33 +00001785
NAKAMURA Takumiaa3d6242011-04-23 00:30:22 +00001786</div>
1787
Chris Lattner1811fca2004-01-05 05:06:33 +00001788<!-- *********************************************************************** -->
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