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Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]6 <title>Source Level Debugging with LLVM</title>
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9<body>
10
11<div class="doc_title">Source Level Debugging with LLVM</div>
12
Reid Spencerc3c4c4f2004-11-01 08:19:36 +0000[diff] [blame]13<table class="layout" style="width:100%">
14 <tr class="layout">
15 <td class="left">
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]16<ul>
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]17 <li><a href="#introduction">Introduction</a>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]18 <ol>
19 <li><a href="#phil">Philosophy behind LLVM debugging information</a></li>
Jim Laskey5dcfd562006-03-23 17:54:33 +0000[diff] [blame]20 <li><a href="#consumers">Debug information consumers</a></li>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]21 <li><a href="#debugopt">Debugging optimized code</a></li>
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]22 </ol></li>
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]23 <li><a href="#format">Debugging information format</a>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]24 <ol>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]25 <li><a href="#debug_info_descriptors">Debug information descriptors</a>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]26 <ul>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]27 <li><a href="#format_compile_units">Compile unit descriptors</a></li>
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]28 <li><a href="#format_files">File descriptors</a></li>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]29 <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 +0000[diff] [blame]31 <li><a href="#format_blocks">Block descriptors</a></li>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]32 <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 +0000[diff] [blame]37 <li><a href="#format_variables">Local variables</a></li>
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]38 </ul></li>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]39 <li><a href="#format_common_intrinsics">Debugger intrinsic functions</a>
40 <ul>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]41 <li><a href="#format_common_declare">llvm.dbg.declare</a></li>
Victor Hernandez0b62cc62010-01-11 22:53:48 +0000[diff] [blame]42 <li><a href="#format_common_value">llvm.dbg.value</a></li>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]43 </ul></li>
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]44 </ol></li>
Devang Patel4da997b2009-11-25 23:28:01 +0000[diff] [blame]45 <li><a href="#format_common_lifetime">Object lifetimes and scoping</a></li>
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]46 <li><a href="#ccxx_frontend">C/C++ front-end specific debug information</a>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]47 <ol>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]48 <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 +0000[diff] [blame]55 </ol></li>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]56</ul>
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]57</td>
Reid Spencerc3c4c4f2004-11-01 08:19:36 +0000[diff] [blame]58<td class="right">
Misha Brukman3c1f8e72004-05-12 21:26:16 +0000[diff] [blame]59<img src="img/venusflytrap.jpg" alt="A leafy and green bug eater" width="247"
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]60height="369">
61</td>
Reid Spencerc3c4c4f2004-11-01 08:19:36 +0000[diff] [blame]62</tr></table>
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]63
Chris Lattner020e1fc2004-05-23 21:07:27 +0000[diff] [blame]64<div class="doc_author">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]65 <p>Written by <a href="mailto:sabre@nondot.org">Chris Lattner</a>
Jim Laskey6e8a2f42007-03-14 19:32:21 +0000[diff] [blame]66 and <a href="mailto:jlaskey@mac.com">Jim Laskey</a></p>
Chris Lattner020e1fc2004-05-23 21:07:27 +0000[diff] [blame]67</div>
68
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]69
70<!-- *********************************************************************** -->
Misha Brukmancda6a9b2004-12-09 20:27:37 +0000[diff] [blame]71<div class="doc_section"><a name="introduction">Introduction</a></div>
72<!-- *********************************************************************** -->
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]73
74<div class="doc_text">
75
76<p>This document is the central repository for all information pertaining to
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]77 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 +0000[diff] [blame]80 Further, this document provides specific examples of what debug information
Chris Lattner92ec3d12011-01-18 06:12:10 +0000[diff] [blame]81 for C/C++ looks like.</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]82
83</div>
84
85<!-- ======================================================================= -->
86<div class="doc_subsection">
87 <a name="phil">Philosophy behind LLVM debugging information</a>
88</div>
89
90<div class="doc_text">
91
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]92<p>The idea of the LLVM debugging information is to capture how the important
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]93 pieces of the source-language's Abstract Syntax Tree map onto LLVM code.
94 Several design aspects have shaped the solution that appears here. The
95 important ones are:</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]96
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]97<ul>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]98 <li>Debugging information should have very little impact on the rest of the
99 compiler. No transformations, analyses, or code generators should need to
100 be modified because of debugging information.</li>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]101
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]102 <li>LLVM optimizations should interact in <a href="#debugopt">well-defined and
103 easily described ways</a> with the debugging information.</li>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]104
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]105 <li>Because LLVM is designed to support arbitrary programming languages,
106 LLVM-to-LLVM tools should not need to know anything about the semantics of
107 the source-level-language.</li>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]108
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]109 <li>Source-level languages are often <b>widely</b> different from one another.
110 LLVM should not put any restrictions of the flavor of the source-language,
111 and the debugging information should work with any language.</li>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]112
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]113 <li>With code generator support, it should be possible to use an LLVM compiler
114 to compile a program to native machine code and standard debugging
115 formats. This allows compatibility with traditional machine-code level
116 debuggers, like GDB or DBX.</li>
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]117</ul>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]118
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]119<p>The approach used by the LLVM implementation is to use a small set
120 of <a href="#format_common_intrinsics">intrinsic functions</a> to define a
121 mapping between LLVM program objects and the source-level objects. The
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]122 description of the source-level program is maintained in LLVM metadata
123 in an <a href="#ccxx_frontend">implementation-defined format</a>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]124 (the C/C++ front-end currently uses working draft 7 of
125 the <a href="http://www.eagercon.com/dwarf/dwarf3std.htm">DWARF 3
126 standard</a>).</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]127
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]128<p>When a program is being debugged, a debugger interacts with the user and
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]129 turns the stored debug information into source-language specific information.
130 As such, a debugger must be aware of the source-language, and is thus tied to
131 a specific language or family of languages.</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]132
133</div>
134
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]135<!-- ======================================================================= -->
136<div class="doc_subsection">
Jim Laskey5dcfd562006-03-23 17:54:33 +0000[diff] [blame]137 <a name="consumers">Debug information consumers</a>
138</div>
139
140<div class="doc_text">
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]141
Jim Laskey5dcfd562006-03-23 17:54:33 +0000[diff] [blame]142<p>The role of debug information is to provide meta information normally
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]143 stripped away during the compilation process. This meta information provides
144 an LLVM user a relationship between generated code and the original program
145 source code.</p>
Jim Laskey5dcfd562006-03-23 17:54:33 +0000[diff] [blame]146
Chris Lattner904f2172010-04-05 04:11:11 +0000[diff] [blame]147<p>Currently, debug information is consumed by DwarfDebug to produce dwarf
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]148 information used by the gdb debugger. Other targets could use the same
149 information to produce stabs or other debug forms.</p>
Jim Laskey5dcfd562006-03-23 17:54:33 +0000[diff] [blame]150
151<p>It would also be reasonable to use debug information to feed profiling tools
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]152 for analysis of generated code, or, tools for reconstructing the original
153 source from generated code.</p>
Jim Laskey5dcfd562006-03-23 17:54:33 +0000[diff] [blame]154
155<p>TODO - expound a bit more.</p>
156
157</div>
158
159<!-- ======================================================================= -->
160<div class="doc_subsection">
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]161 <a name="debugopt">Debugging optimized code</a>
162</div>
163
164<div class="doc_text">
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]165
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]166<p>An extremely high priority of LLVM debugging information is to make it
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]167 interact well with optimizations and analysis. In particular, the LLVM debug
168 information provides the following guarantees:</p>
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]169
170<ul>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]171 <li>LLVM debug information <b>always provides information to accurately read
172 the source-level state of the program</b>, regardless of which LLVM
173 optimizations have been run, and without any modification to the
174 optimizations themselves. However, some optimizations may impact the
175 ability to modify the current state of the program with a debugger, such
176 as setting program variables, or calling functions that have been
177 deleted.</li>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]178
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]179 <li>LLVM optimizations gracefully interact with debugging information. If
180 they are not aware of debug information, they are automatically disabled
181 as necessary in the cases that would invalidate the debug info. This
182 retains the LLVM features, making it easy to write new
183 transformations.</li>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]184
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]185 <li>As desired, LLVM optimizations can be upgraded to be aware of the LLVM
186 debugging information, allowing them to update the debugging information
187 as they perform aggressive optimizations. This means that, with effort,
188 the LLVM optimizers could optimize debug code just as well as non-debug
189 code.</li>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]190
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]191 <li>LLVM debug information does not prevent many important optimizations from
192 happening (for example inlining, basic block reordering/merging/cleanup,
193 tail duplication, etc), further reducing the amount of the compiler that
194 eventually is "aware" of debugging information.</li>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]195
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]196 <li>LLVM debug information is automatically optimized along with the rest of
197 the program, using existing facilities. For example, duplicate
198 information is automatically merged by the linker, and unused information
199 is automatically removed.</li>
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]200</ul>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]201
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]202<p>Basically, the debug information allows you to compile a program with
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]203 "<tt>-O0 -g</tt>" and get full debug information, allowing you to arbitrarily
204 modify the program as it executes from a debugger. Compiling a program with
205 "<tt>-O3 -g</tt>" gives you full debug information that is always available
206 and accurate for reading (e.g., you get accurate stack traces despite tail
207 call elimination and inlining), but you might lose the ability to modify the
208 program and call functions where were optimized out of the program, or
209 inlined away completely.</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]210
Misha Brukman39dcddf2008-12-16 02:54:22 +0000[diff] [blame]211<p><a href="TestingGuide.html#quicktestsuite">LLVM test suite</a> provides a
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]212 framework to test optimizer's handling of debugging information. It can be
213 run like this:</p>
Devang Patelb885a912008-11-21 19:35:57 +0000[diff] [blame]214
215<div class="doc_code">
216<pre>
217% cd llvm/projects/test-suite/MultiSource/Benchmarks # or some other level
218% make TEST=dbgopt
219</pre>
220</div>
221
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]222<p>This will test impact of debugging information on optimization passes. If
223 debugging information influences optimization passes then it will be reported
224 as a failure. See <a href="TestingGuide.html">TestingGuide</a> for more
225 information on LLVM test infrastructure and how to run various tests.</p>
Devang Patelb885a912008-11-21 19:35:57 +0000[diff] [blame]226
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]227</div>
228
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]229<!-- *********************************************************************** -->
230<div class="doc_section">
Chris Lattner941515c2004-01-06 05:31:32 +0000[diff] [blame]231 <a name="format">Debugging information format</a>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]232</div>
233<!-- *********************************************************************** -->
234
235<div class="doc_text">
236
237<p>LLVM debugging information has been carefully designed to make it possible
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]238 for the optimizer to optimize the program and debugging information without
239 necessarily having to know anything about debugging information. In
John Criswell2a4b0802010-03-17 15:01:50 +0000[diff] [blame]240 particular, the use of metadata avoids duplicated debugging information from
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]241 the beginning, and the global dead code elimination pass automatically
242 deletes debugging information for a function if it decides to delete the
243 function. </p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]244
245<p>To do this, most of the debugging information (descriptors for types,
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]246 variables, functions, source files, etc) is inserted by the language
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]247 front-end in the form of LLVM metadata. </p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]248
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]249<p>Debug information is designed to be agnostic about the target debugger and
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]250 debugging information representation (e.g. DWARF/Stabs/etc). It uses a
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]251 generic pass to decode the information that represents variables, types,
252 functions, namespaces, etc: this allows for arbitrary source-language
253 semantics and type-systems to be used, as long as there is a module
254 written for the target debugger to interpret the information. </p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]255
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]256<p>To provide basic functionality, the LLVM debugger does have to make some
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]257 assumptions about the source-level language being debugged, though it keeps
258 these to a minimum. The only common features that the LLVM debugger assumes
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]259 exist are <a href="#format_files">source files</a>,
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]260 and <a href="#format_global_variables">program objects</a>. These abstract
261 objects are used by a debugger to form stack traces, show information about
262 local variables, etc.</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]263
264<p>This section of the documentation first describes the representation aspects
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]265 common to any source-language. The <a href="#ccxx_frontend">next section</a>
266 describes the data layout conventions used by the C and C++ front-ends.</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]267
268</div>
269
270<!-- ======================================================================= -->
271<div class="doc_subsection">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]272 <a name="debug_info_descriptors">Debug information descriptors</a>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]273</div>
274
275<div class="doc_text">
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]276
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]277<p>In consideration of the complexity and volume of debug information, LLVM
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]278 provides a specification for well formed debug descriptors. </p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]279
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]280<p>Consumers of LLVM debug information expect the descriptors for program
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]281 objects to start in a canonical format, but the descriptors can include
282 additional information appended at the end that is source-language
283 specific. All LLVM debugging information is versioned, allowing backwards
284 compatibility in the case that the core structures need to change in some
285 way. Also, all debugging information objects start with a tag to indicate
286 what type of object it is. The source-language is allowed to define its own
287 objects, by using unreserved tag numbers. We recommend using with tags in
Benjamin Kramer0f420382009-10-12 14:46:08 +0000[diff] [blame]288 the range 0x1000 through 0x2000 (there is a defined enum DW_TAG_user_base =
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]289 0x1000.)</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]290
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]291<p>The fields of debug descriptors used internally by LLVM
Nick Lewyckya87014f2010-03-31 07:50:17 +0000[diff] [blame]292 are restricted to only the simple data types <tt>i32</tt>, <tt>i1</tt>,
293 <tt>float</tt>, <tt>double</tt>, <tt>mdstring</tt> and <tt>mdnode</tt>. </p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]294
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]295<div class="doc_code">
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]296<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]297!1 = metadata !{
Nick Lewyckya87014f2010-03-31 07:50:17 +0000[diff] [blame]298 i32, ;; A tag
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]299 ...
300}
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]301</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]302</div>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]303
Jim Laskeyb2ff2d42006-06-16 13:14:03 +0000[diff] [blame]304<p><a name="LLVMDebugVersion">The first field of a descriptor is always an
Nick Lewyckya87014f2010-03-31 07:50:17 +0000[diff] [blame]305 <tt>i32</tt> containing a tag value identifying the content of the
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]306 descriptor. The remaining fields are specific to the descriptor. The values
307 of tags are loosely bound to the tag values of DWARF information entries.
308 However, that does not restrict the use of the information supplied to DWARF
309 targets. To facilitate versioning of debug information, the tag is augmented
Nick Lewyckya87014f2010-03-31 07:50:17 +0000[diff] [blame]310 with the current debug version (LLVMDebugVersion = 8 &lt;&lt; 16 or 0x80000 or
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]311 524288.)</a></p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]312
Jim Laskeyb2ff2d42006-06-16 13:14:03 +0000[diff] [blame]313<p>The details of the various descriptors follow.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]314
315</div>
316
317<!-- ======================================================================= -->
318<div class="doc_subsubsection">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]319 <a name="format_compile_units">Compile unit descriptors</a>
320</div>
321
322<div class="doc_text">
323
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]324<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]325<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]326!0 = metadata !{
327 i32, ;; Tag = 17 + <a href="#LLVMDebugVersion">LLVMDebugVersion</a>
328 ;; (DW_TAG_compile_unit)
329 i32, ;; Unused field.
330 i32, ;; DWARF language identifier (ex. DW_LANG_C89)
331 metadata, ;; Source file name
332 metadata, ;; Source file directory (includes trailing slash)
333 metadata ;; Producer (ex. "4.0.1 LLVM (LLVM research group)")
334 i1, ;; True if this is a main compile unit.
335 i1, ;; True if this is optimized.
336 metadata, ;; Flags
337 i32 ;; Runtime version
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]338}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]339</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]340</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]341
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]342<p>These descriptors contain a source language ID for the file (we use the DWARF
343 3.0 ID numbers, such as <tt>DW_LANG_C89</tt>, <tt>DW_LANG_C_plus_plus</tt>,
344 <tt>DW_LANG_Cobol74</tt>, etc), three strings describing the filename,
345 working directory of the compiler, and an identifier string for the compiler
346 that produced it.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]347
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]348<p>Compile unit descriptors provide the root context for objects declared in a
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]349 specific compilation unit. File descriptors are defined using this context.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]350
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]351</div>
352
353<!-- ======================================================================= -->
354<div class="doc_subsubsection">
355 <a name="format_files">File descriptors</a>
356</div>
357
358<div class="doc_text">
359
360<div class="doc_code">
361<pre>
362!0 = metadata !{
363 i32, ;; Tag = 41 + <a href="#LLVMDebugVersion">LLVMDebugVersion</a>
364 ;; (DW_TAG_file_type)
365 metadata, ;; Source file name
366 metadata, ;; Source file directory (includes trailing slash)
367 metadata ;; Reference to compile unit where defined
368}
369</pre>
370</div>
371
John Criswell2a4b0802010-03-17 15:01:50 +0000[diff] [blame]372<p>These descriptors contain information for a file. Global variables and top
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]373 level functions would be defined using this context.k File descriptors also
374 provide context for source line correspondence. </p>
375
376<p>Each input file is encoded as a separate file descriptor in LLVM debugging
377 information output. Each file descriptor would be defined using a
378 compile unit. </p>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]379
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]380</div>
381
382<!-- ======================================================================= -->
383<div class="doc_subsubsection">
384 <a name="format_global_variables">Global variable descriptors</a>
385</div>
386
387<div class="doc_text">
388
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]389<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]390<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]391!1 = metadata !{
392 i32, ;; Tag = 52 + <a href="#LLVMDebugVersion">LLVMDebugVersion</a>
393 ;; (DW_TAG_variable)
394 i32, ;; Unused field.
395 metadata, ;; Reference to context descriptor
396 metadata, ;; Name
397 metadata, ;; Display name (fully qualified C++ name)
398 metadata, ;; MIPS linkage name (for C++)
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]399 metadata, ;; Reference to file where defined
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]400 i32, ;; Line number where defined
401 metadata, ;; Reference to type descriptor
402 i1, ;; True if the global is local to compile unit (static)
403 i1, ;; True if the global is defined in the compile unit (not extern)
Dan Gohmanaabfdb32010-05-28 17:13:49 +0000[diff] [blame]404 {}* ;; Reference to the global variable
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]405}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]406</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]407</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]408
409<p>These descriptors provide debug information about globals variables. The
Devang Patel1c6b6812011-03-29 17:27:08 +0000[diff] [blame]410provide details such as name, type and where the variable is defined. All
411global variables are collected by named metadata <tt>!llvm.dbg.gv</tt>.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]412
413</div>
414
415<!-- ======================================================================= -->
416<div class="doc_subsubsection">
417 <a name="format_subprograms">Subprogram descriptors</a>
418</div>
419
420<div class="doc_text">
421
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]422<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]423<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]424!2 = metadata !{
425 i32, ;; Tag = 46 + <a href="#LLVMDebugVersion">LLVMDebugVersion</a>
426 ;; (DW_TAG_subprogram)
427 i32, ;; Unused field.
428 metadata, ;; Reference to context descriptor
429 metadata, ;; Name
430 metadata, ;; Display name (fully qualified C++ name)
431 metadata, ;; MIPS linkage name (for C++)
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]432 metadata, ;; Reference to file where defined
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]433 i32, ;; Line number where defined
434 metadata, ;; Reference to type descriptor
435 i1, ;; True if the global is local to compile unit (static)
436 i1 ;; True if the global is defined in the compile unit (not extern)
Devang Patele89b7592010-06-04 22:49:55 +0000[diff] [blame]437 i32 ;; Virtuality, e.g. dwarf::DW_VIRTUALITY__virtual
438 i32 ;; Index into a virtual function
439 metadata, ;; indicates which base type contains the vtable pointer for the
440 ;; derived class
441 i1 ;; isArtificial
442 i1 ;; isOptimized
443 Function *;; Pointer to LLVM function
Devang Patel9f738842011-04-05 22:52:06 +0000[diff] [blame]444 metadata ;; Lists function template parameters
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]445}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]446</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]447</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]448
449<p>These descriptors provide debug information about functions, methods and
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]450 subprograms. They provide details such as name, return types and the source
Devang Patel1c6b6812011-03-29 17:27:08 +0000[diff] [blame]451 location where the subprogram is defined.
452 All subprogram descriptors are collected by a named metadata
453 <tt>!llvm.dbg.sp</tt>.
454</p>
Jim Laskey9dcffe72006-03-15 19:10:52 +0000[diff] [blame]455
456</div>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]457
Jim Laskey9dcffe72006-03-15 19:10:52 +0000[diff] [blame]458<!-- ======================================================================= -->
459<div class="doc_subsubsection">
460 <a name="format_blocks">Block descriptors</a>
461</div>
462
463<div class="doc_text">
464
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]465<div class="doc_code">
Jim Laskey9dcffe72006-03-15 19:10:52 +0000[diff] [blame]466<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]467!3 = metadata !{
Devang Patel9fbc6802010-10-04 16:51:59 +0000[diff] [blame]468 i32, ;; Tag = 11 + <a href="#LLVMDebugVersion">LLVMDebugVersion</a> (DW_TAG_lexical_block)
Devang Patelcac38902010-10-01 22:45:00 +0000[diff] [blame]469 metadata,;; Reference to context descriptor
470 i32, ;; Line number
Devang Patelfb30b852011-03-08 16:25:29 +0000[diff] [blame]471 i32, ;; Column number
472 metadata,;; Reference to source file
473 i32 ;; Unique ID to identify blocks from a template function
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]474}
Jim Laskey9dcffe72006-03-15 19:10:52 +0000[diff] [blame]475</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]476</div>
Jim Laskey9dcffe72006-03-15 19:10:52 +0000[diff] [blame]477
478<p>These descriptors provide debug information about nested blocks within a
Devang Patelcac38902010-10-01 22:45:00 +0000[diff] [blame]479 subprogram. The line number and column numbers are used to dinstinguish
480 two lexical blocks at same depth. </p>
Jim Laskey9dcffe72006-03-15 19:10:52 +0000[diff] [blame]481
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]482</div>
483
484<!-- ======================================================================= -->
485<div class="doc_subsubsection">
486 <a name="format_basic_type">Basic type descriptors</a>
487</div>
488
489<div class="doc_text">
490
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]491<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]492<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]493!4 = metadata !{
494 i32, ;; Tag = 36 + <a href="#LLVMDebugVersion">LLVMDebugVersion</a>
495 ;; (DW_TAG_base_type)
496 metadata, ;; Reference to context (typically a compile unit)
497 metadata, ;; Name (may be "" for anonymous types)
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]498 metadata, ;; Reference to file where defined (may be NULL)
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]499 i32, ;; Line number where defined (may be 0)
500 i64, ;; Size in bits
501 i64, ;; Alignment in bits
502 i64, ;; Offset in bits
503 i32, ;; Flags
504 i32 ;; DWARF type encoding
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]505}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]506</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]507</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]508
509<p>These descriptors define primitive types used in the code. Example int, bool
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]510 and float. The context provides the scope of the type, which is usually the
511 top level. Since basic types are not usually user defined the compile unit
512 and line number can be left as NULL and 0. The size, alignment and offset
513 are expressed in bits and can be 64 bit values. The alignment is used to
514 round the offset when embedded in a
515 <a href="#format_composite_type">composite type</a> (example to keep float
516 doubles on 64 bit boundaries.) The offset is the bit offset if embedded in
517 a <a href="#format_composite_type">composite type</a>.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]518
519<p>The type encoding provides the details of the type. The values are typically
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]520 one of the following:</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]521
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]522<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]523<pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]524DW_ATE_address = 1
525DW_ATE_boolean = 2
526DW_ATE_float = 4
527DW_ATE_signed = 5
528DW_ATE_signed_char = 6
529DW_ATE_unsigned = 7
530DW_ATE_unsigned_char = 8
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]531</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]532</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]533
534</div>
535
536<!-- ======================================================================= -->
537<div class="doc_subsubsection">
538 <a name="format_derived_type">Derived type descriptors</a>
539</div>
540
541<div class="doc_text">
542
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]543<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]544<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]545!5 = metadata !{
546 i32, ;; Tag (see below)
547 metadata, ;; Reference to context
548 metadata, ;; Name (may be "" for anonymous types)
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]549 metadata, ;; Reference to file where defined (may be NULL)
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]550 i32, ;; Line number where defined (may be 0)
Devang Patelbed5e7d2010-10-01 19:19:30 +0000[diff] [blame]551 i64, ;; Size in bits
552 i64, ;; Alignment in bits
553 i64, ;; Offset in bits
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]554 metadata ;; Reference to type derived from
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]555}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]556</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]557</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]558
559<p>These descriptors are used to define types derived from other types. The
560value of the tag varies depending on the meaning. The following are possible
Misha Brukman39dcddf2008-12-16 02:54:22 +0000[diff] [blame]561tag values:</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]562
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]563<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]564<pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]565DW_TAG_formal_parameter = 5
566DW_TAG_member = 13
567DW_TAG_pointer_type = 15
568DW_TAG_reference_type = 16
569DW_TAG_typedef = 22
570DW_TAG_const_type = 38
571DW_TAG_volatile_type = 53
572DW_TAG_restrict_type = 55
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]573</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]574</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]575
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]576<p><tt>DW_TAG_member</tt> is used to define a member of
577 a <a href="#format_composite_type">composite type</a>
578 or <a href="#format_subprograms">subprogram</a>. The type of the member is
579 the <a href="#format_derived_type">derived
580 type</a>. <tt>DW_TAG_formal_parameter</tt> is used to define a member which
581 is a formal argument of a subprogram.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]582
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]583<p><tt>DW_TAG_typedef</tt> is used to provide a name for the derived type.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]584
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]585<p><tt>DW_TAG_pointer_type</tt>,<tt>DW_TAG_reference_type</tt>,
586 <tt>DW_TAG_const_type</tt>, <tt>DW_TAG_volatile_type</tt>
587 and <tt>DW_TAG_restrict_type</tt> are used to qualify
588 the <a href="#format_derived_type">derived type</a>. </p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]589
590<p><a href="#format_derived_type">Derived type</a> location can be determined
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]591 from the compile unit and line number. The size, alignment and offset are
592 expressed in bits and can be 64 bit values. The alignment is used to round
593 the offset when embedded in a <a href="#format_composite_type">composite
594 type</a> (example to keep float doubles on 64 bit boundaries.) The offset is
595 the bit offset if embedded in a <a href="#format_composite_type">composite
596 type</a>.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]597
Devang Patel7846c1e2011-02-03 00:22:17 +0000[diff] [blame]598<p>Note that the <tt>void *</tt> type is expressed as a type derived from NULL.
599</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]600
601</div>
602
603<!-- ======================================================================= -->
604<div class="doc_subsubsection">
605 <a name="format_composite_type">Composite type descriptors</a>
606</div>
607
608<div class="doc_text">
609
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]610<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]611<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]612!6 = metadata !{
613 i32, ;; Tag (see below)
614 metadata, ;; Reference to context
615 metadata, ;; Name (may be "" for anonymous types)
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]616 metadata, ;; Reference to file where defined (may be NULL)
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]617 i32, ;; Line number where defined (may be 0)
618 i64, ;; Size in bits
619 i64, ;; Alignment in bits
620 i64, ;; Offset in bits
621 i32, ;; Flags
622 metadata, ;; Reference to type derived from
623 metadata, ;; Reference to array of member descriptors
624 i32 ;; Runtime languages
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]625}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]626</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]627</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]628
629<p>These descriptors are used to define types that are composed of 0 or more
630elements. The value of the tag varies depending on the meaning. The following
Misha Brukman39dcddf2008-12-16 02:54:22 +0000[diff] [blame]631are possible tag values:</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]632
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]633<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]634<pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]635DW_TAG_array_type = 1
636DW_TAG_enumeration_type = 4
637DW_TAG_structure_type = 19
638DW_TAG_union_type = 23
639DW_TAG_vector_type = 259
Bruno Cardoso Lopes9d809ca2009-05-29 17:08:57 +0000[diff] [blame]640DW_TAG_subroutine_type = 21
641DW_TAG_inheritance = 28
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]642</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]643</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]644
Jim Laskey19f964e2006-06-15 20:51:43 +0000[diff] [blame]645<p>The vector flag indicates that an array type is a native packed vector.</p>
646
Jim Laskeyb2ff2d42006-06-16 13:14:03 +0000[diff] [blame]647<p>The members of array types (tag = <tt>DW_TAG_array_type</tt>) or vector types
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]648 (tag = <tt>DW_TAG_vector_type</tt>) are <a href="#format_subrange">subrange
649 descriptors</a>, each representing the range of subscripts at that level of
650 indexing.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]651
652<p>The members of enumeration types (tag = <tt>DW_TAG_enumeration_type</tt>) are
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]653 <a href="#format_enumeration">enumerator descriptors</a>, each representing
Devang Patel1c6b6812011-03-29 17:27:08 +0000[diff] [blame]654 the definition of enumeration value for the set. All enumeration type
655 descriptors are collected by named metadata <tt>!llvm.dbg.enum</tt>.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]656
657<p>The members of structure (tag = <tt>DW_TAG_structure_type</tt>) or union (tag
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]658 = <tt>DW_TAG_union_type</tt>) types are any one of
659 the <a href="#format_basic_type">basic</a>,
660 <a href="#format_derived_type">derived</a>
661 or <a href="#format_composite_type">composite</a> type descriptors, each
662 representing a field member of the structure or union.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]663
Jim Laskey4771cca2006-08-21 21:21:06 +0000[diff] [blame]664<p>For C++ classes (tag = <tt>DW_TAG_structure_type</tt>), member descriptors
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]665 provide information about base classes, static members and member
666 functions. If a member is a <a href="#format_derived_type">derived type
667 descriptor</a> and has a tag of <tt>DW_TAG_inheritance</tt>, then the type
668 represents a base class. If the member of is
669 a <a href="#format_global_variables">global variable descriptor</a> then it
670 represents a static member. And, if the member is
671 a <a href="#format_subprograms">subprogram descriptor</a> then it represents
672 a member function. For static members and member
673 functions, <tt>getName()</tt> returns the members link or the C++ mangled
674 name. <tt>getDisplayName()</tt> the simplied version of the name.</p>
Jim Laskey4771cca2006-08-21 21:21:06 +0000[diff] [blame]675
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]676<p>The first member of subroutine (tag = <tt>DW_TAG_subroutine_type</tt>) type
677 elements is the return type for the subroutine. The remaining elements are
678 the formal arguments to the subroutine.</p>
Jim Laskey4810c262006-06-20 21:13:20 +0000[diff] [blame]679
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]680<p><a href="#format_composite_type">Composite type</a> location can be
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]681 determined from the compile unit and line number. The size, alignment and
682 offset are expressed in bits and can be 64 bit values. The alignment is used
683 to round the offset when embedded in
684 a <a href="#format_composite_type">composite type</a> (as an example, to keep
685 float doubles on 64 bit boundaries.) The offset is the bit offset if embedded
686 in a <a href="#format_composite_type">composite type</a>.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]687
688</div>
689
690<!-- ======================================================================= -->
691<div class="doc_subsubsection">
692 <a name="format_subrange">Subrange descriptors</a>
693</div>
694
695<div class="doc_text">
696
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]697<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]698<pre>
Devang Patel7846c1e2011-02-03 00:22:17 +0000[diff] [blame]699!42 = metadata !{
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]700 i32, ;; Tag = 33 + <a href="#LLVMDebugVersion">LLVMDebugVersion</a> (DW_TAG_subrange_type)
701 i64, ;; Low value
702 i64 ;; High value
703}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]704</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]705</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]706
707<p>These descriptors are used to define ranges of array subscripts for an array
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]708 <a href="#format_composite_type">composite type</a>. The low value defines
709 the lower bounds typically zero for C/C++. The high value is the upper
710 bounds. Values are 64 bit. High - low + 1 is the size of the array. If low
Devang Patel778947c2011-04-08 23:39:38 +0000[diff] [blame]711 > high the array bounds are not included in generated debugging information.
712</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]713
714</div>
715
716<!-- ======================================================================= -->
717<div class="doc_subsubsection">
718 <a name="format_enumeration">Enumerator descriptors</a>
719</div>
720
721<div class="doc_text">
722
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]723<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]724<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]725!6 = metadata !{
726 i32, ;; Tag = 40 + <a href="#LLVMDebugVersion">LLVMDebugVersion</a>
727 ;; (DW_TAG_enumerator)
728 metadata, ;; Name
729 i64 ;; Value
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]730}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]731</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]732</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]733
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]734<p>These descriptors are used to define members of an
735 enumeration <a href="#format_composite_type">composite type</a>, it
736 associates the name to the value.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]737
738</div>
739
740<!-- ======================================================================= -->
Jim Laskey5dcfd562006-03-23 17:54:33 +0000[diff] [blame]741<div class="doc_subsubsection">
742 <a name="format_variables">Local variables</a>
743</div>
744
745<div class="doc_text">
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]746
747<div class="doc_code">
Jim Laskey5dcfd562006-03-23 17:54:33 +0000[diff] [blame]748<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]749!7 = metadata !{
750 i32, ;; Tag (see below)
751 metadata, ;; Context
752 metadata, ;; Name
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]753 metadata, ;; Reference to file where defined
Devang Patele1aa67c2011-03-08 16:29:40 +0000[diff] [blame]754 i32, ;; 24 bit - Line number where defined
755 ;; 8 bit - Argument number. 1 indicates 1st argument.
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]756 metadata ;; Type descriptor
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]757}
Jim Laskey5dcfd562006-03-23 17:54:33 +0000[diff] [blame]758</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]759</div>
Jim Laskey5dcfd562006-03-23 17:54:33 +0000[diff] [blame]760
761<p>These descriptors are used to define variables local to a sub program. The
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]762 value of the tag depends on the usage of the variable:</p>
Jim Laskey5dcfd562006-03-23 17:54:33 +0000[diff] [blame]763
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]764<div class="doc_code">
Jim Laskey5dcfd562006-03-23 17:54:33 +0000[diff] [blame]765<pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]766DW_TAG_auto_variable = 256
767DW_TAG_arg_variable = 257
768DW_TAG_return_variable = 258
Jim Laskey5dcfd562006-03-23 17:54:33 +0000[diff] [blame]769</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]770</div>
Jim Laskey5dcfd562006-03-23 17:54:33 +0000[diff] [blame]771
772<p>An auto variable is any variable declared in the body of the function. An
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]773 argument variable is any variable that appears as a formal argument to the
774 function. A return variable is used to track the result of a function and
775 has no source correspondent.</p>
Jim Laskey5dcfd562006-03-23 17:54:33 +0000[diff] [blame]776
Jim Laskey3481e122006-03-24 09:20:27 +0000[diff] [blame]777<p>The context is either the subprogram or block where the variable is defined.
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]778 Name the source variable name. Compile unit and line indicate where the
779 variable was defined. Type descriptor defines the declared type of the
780 variable.</p>
Jim Laskey5dcfd562006-03-23 17:54:33 +0000[diff] [blame]781
782</div>
783
784<!-- ======================================================================= -->
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]785<div class="doc_subsection">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]786 <a name="format_common_intrinsics">Debugger intrinsic functions</a>
787</div>
788
789<div class="doc_text">
790
791<p>LLVM uses several intrinsic functions (name prefixed with "llvm.dbg") to
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]792 provide debug information at various points in generated code.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]793
794</div>
795
796<!-- ======================================================================= -->
797<div class="doc_subsubsection">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]798 <a name="format_common_declare">llvm.dbg.declare</a>
799</div>
800
801<div class="doc_text">
802<pre>
Devang Patel6df452c2010-10-01 19:22:16 +0000[diff] [blame]803 void %<a href="#format_common_declare">llvm.dbg.declare</a>(metadata, metadata)
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]804</pre>
805
Jim Laskey3481e122006-03-24 09:20:27 +0000[diff] [blame]806<p>This intrinsic provides information about a local element (ex. variable.) The
Devang Patel6df452c2010-10-01 19:22:16 +0000[diff] [blame]807 first argument is metadata holding alloca for the variable.</tt>. The
Devang Patel9a8539c2011-02-01 17:22:12 +0000[diff] [blame]808 second argument is metadata containing description of the variable. </p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]809</div>
810
811<!-- ======================================================================= -->
Victor Hernandez0b62cc62010-01-11 22:53:48 +0000[diff] [blame]812<div class="doc_subsubsection">
813 <a name="format_common_value">llvm.dbg.value</a>
814</div>
815
816<div class="doc_text">
817<pre>
Dan Gohmand6a6f612010-05-28 17:07:41 +0000[diff] [blame]818 void %<a href="#format_common_value">llvm.dbg.value</a>(metadata, i64, metadata)
Victor Hernandez0b62cc62010-01-11 22:53:48 +0000[diff] [blame]819</pre>
820
821<p>This intrinsic provides information when a user source variable is set to a
822 new value. The first argument is the new value (wrapped as metadata). The
823 second argument is the offset in the user source variable where the new value
Devang Patel9a8539c2011-02-01 17:22:12 +0000[diff] [blame]824 is written. The third argument is metadata containing description of the
825 user source variable. </p>
Victor Hernandez0b62cc62010-01-11 22:53:48 +0000[diff] [blame]826</div>
827
828<!-- ======================================================================= -->
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]829<div class="doc_subsection">
Chris Lattner941515c2004-01-06 05:31:32 +0000[diff] [blame]830 <a name="format_common_lifetime">Object lifetimes and scoping</a>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]831</div>
832
833<div class="doc_text">
Bill Wendling991b84e2009-12-01 00:53:11 +0000[diff] [blame]834<p>In many languages, the local variables in functions can have their lifetimes
835 or scopes limited to a subset of a function. In the C family of languages,
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]836 for example, variables are only live (readable and writable) within the
837 source block that they are defined in. In functional languages, values are
838 only readable after they have been defined. Though this is a very obvious
Bill Wendling991b84e2009-12-01 00:53:11 +0000[diff] [blame]839 concept, it is non-trivial to model in LLVM, because it has no notion of
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]840 scoping in this sense, and does not want to be tied to a language's scoping
841 rules.</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]842
Bill Wendling991b84e2009-12-01 00:53:11 +0000[diff] [blame]843<p>In order to handle this, the LLVM debug format uses the metadata attached to
Nick Lewyckya87014f2010-03-31 07:50:17 +0000[diff] [blame]844 llvm instructions to encode line number and scoping information. Consider
845 the following C fragment, for example:</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]846
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]847<div class="doc_code">
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]848<pre>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]8491. void foo() {
Devang Patel4da997b2009-11-25 23:28:01 +0000[diff] [blame]8502. int X = 21;
8513. int Y = 22;
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]8524. {
Devang Patel4da997b2009-11-25 23:28:01 +0000[diff] [blame]8535. int Z = 23;
8546. Z = X;
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]8557. }
Devang Patel4da997b2009-11-25 23:28:01 +0000[diff] [blame]8568. X = Y;
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]8579. }
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]858</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]859</div>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]860
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]861<p>Compiled to LLVM, this function would be represented like this:</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]862
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]863<div class="doc_code">
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]864<pre>
Bill Wendling991b84e2009-12-01 00:53:11 +0000[diff] [blame]865define void @foo() nounwind ssp {
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]866entry:
Bill Wendling05252352009-12-01 00:59:58 +0000[diff] [blame]867 %X = alloca i32, align 4 ; &lt;i32*&gt; [#uses=4]
868 %Y = alloca i32, align 4 ; &lt;i32*&gt; [#uses=4]
869 %Z = alloca i32, align 4 ; &lt;i32*&gt; [#uses=3]
Dan Gohmanaabfdb32010-05-28 17:13:49 +0000[diff] [blame]870 %0 = bitcast i32* %X to {}* ; &lt;{}*&gt; [#uses=1]
Devang Patel7846c1e2011-02-03 00:22:17 +0000[diff] [blame]871 call void @llvm.dbg.declare(metadata !{i32 * %X}, metadata !0), !dbg !7
Devang Patel4da997b2009-11-25 23:28:01 +0000[diff] [blame]872 store i32 21, i32* %X, !dbg !8
Dan Gohmanaabfdb32010-05-28 17:13:49 +0000[diff] [blame]873 %1 = bitcast i32* %Y to {}* ; &lt;{}*&gt; [#uses=1]
Devang Patel7846c1e2011-02-03 00:22:17 +0000[diff] [blame]874 call void @llvm.dbg.declare(metadata !{i32 * %Y}, metadata !9), !dbg !10
Devang Patel4da997b2009-11-25 23:28:01 +0000[diff] [blame]875 store i32 22, i32* %Y, !dbg !11
Dan Gohmanaabfdb32010-05-28 17:13:49 +0000[diff] [blame]876 %2 = bitcast i32* %Z to {}* ; &lt;{}*&gt; [#uses=1]
Devang Patel7846c1e2011-02-03 00:22:17 +0000[diff] [blame]877 call void @llvm.dbg.declare(metadata !{i32 * %Z}, metadata !12), !dbg !14
Devang Patel4da997b2009-11-25 23:28:01 +0000[diff] [blame]878 store i32 23, i32* %Z, !dbg !15
Bill Wendling05252352009-12-01 00:59:58 +0000[diff] [blame]879 %tmp = load i32* %X, !dbg !16 ; &lt;i32&gt; [#uses=1]
880 %tmp1 = load i32* %Y, !dbg !16 ; &lt;i32&gt; [#uses=1]
881 %add = add nsw i32 %tmp, %tmp1, !dbg !16 ; &lt;i32&gt; [#uses=1]
Devang Patel4da997b2009-11-25 23:28:01 +0000[diff] [blame]882 store i32 %add, i32* %Z, !dbg !16
Bill Wendling05252352009-12-01 00:59:58 +0000[diff] [blame]883 %tmp2 = load i32* %Y, !dbg !17 ; &lt;i32&gt; [#uses=1]
Devang Patel4da997b2009-11-25 23:28:01 +0000[diff] [blame]884 store i32 %tmp2, i32* %X, !dbg !17
885 ret void, !dbg !18
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]886}
Devang Patel4da997b2009-11-25 23:28:01 +0000[diff] [blame]887
Devang Patel7846c1e2011-02-03 00:22:17 +0000[diff] [blame]888declare void @llvm.dbg.declare(metadata, metadata) nounwind readnone
Devang Patel4da997b2009-11-25 23:28:01 +0000[diff] [blame]889
890!0 = metadata !{i32 459008, metadata !1, metadata !"X",
891 metadata !3, i32 2, metadata !6}; [ DW_TAG_auto_variable ]
892!1 = metadata !{i32 458763, metadata !2}; [DW_TAG_lexical_block ]
893!2 = metadata !{i32 458798, i32 0, metadata !3, metadata !"foo", metadata !"foo",
894 metadata !"foo", metadata !3, i32 1, metadata !4,
895 i1 false, i1 true}; [DW_TAG_subprogram ]
896!3 = metadata !{i32 458769, i32 0, i32 12, metadata !"foo.c",
897 metadata !"/private/tmp", metadata !"clang 1.1", i1 true,
898 i1 false, metadata !"", i32 0}; [DW_TAG_compile_unit ]
899!4 = metadata !{i32 458773, metadata !3, metadata !"", null, i32 0, i64 0, i64 0,
900 i64 0, i32 0, null, metadata !5, i32 0}; [DW_TAG_subroutine_type ]
901!5 = metadata !{null}
902!6 = metadata !{i32 458788, metadata !3, metadata !"int", metadata !3, i32 0,
903 i64 32, i64 32, i64 0, i32 0, i32 5}; [DW_TAG_base_type ]
904!7 = metadata !{i32 2, i32 7, metadata !1, null}
905!8 = metadata !{i32 2, i32 3, metadata !1, null}
906!9 = metadata !{i32 459008, metadata !1, metadata !"Y", metadata !3, i32 3,
907 metadata !6}; [ DW_TAG_auto_variable ]
908!10 = metadata !{i32 3, i32 7, metadata !1, null}
909!11 = metadata !{i32 3, i32 3, metadata !1, null}
910!12 = metadata !{i32 459008, metadata !13, metadata !"Z", metadata !3, i32 5,
911 metadata !6}; [ DW_TAG_auto_variable ]
912!13 = metadata !{i32 458763, metadata !1}; [DW_TAG_lexical_block ]
913!14 = metadata !{i32 5, i32 9, metadata !13, null}
914!15 = metadata !{i32 5, i32 5, metadata !13, null}
915!16 = metadata !{i32 6, i32 5, metadata !13, null}
916!17 = metadata !{i32 8, i32 3, metadata !1, null}
917!18 = metadata !{i32 9, i32 1, metadata !2, null}
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]918</pre>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]919</div>
920
Bill Wendling991b84e2009-12-01 00:53:11 +0000[diff] [blame]921<p>This example illustrates a few important details about LLVM debugging
922 information. In particular, it shows how the <tt>llvm.dbg.declare</tt>
923 intrinsic and location information, which are attached to an instruction,
924 are applied together to allow a debugger to analyze the relationship between
925 statements, variable definitions, and the code used to implement the
926 function.</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]927
Bill Wendling991b84e2009-12-01 00:53:11 +0000[diff] [blame]928<div class="doc_code">
Bill Wendling05252352009-12-01 00:59:58 +0000[diff] [blame]929<pre>
Devang Patel7846c1e2011-02-03 00:22:17 +0000[diff] [blame]930call void @llvm.dbg.declare(metadata, metadata !0), !dbg !7
Bill Wendling991b84e2009-12-01 00:53:11 +0000[diff] [blame]931</pre>
932</div>
933
934<p>The first intrinsic
Devang Patel4da997b2009-11-25 23:28:01 +0000[diff] [blame]935 <tt>%<a href="#format_common_declare">llvm.dbg.declare</a></tt>
Bill Wendling991b84e2009-12-01 00:53:11 +0000[diff] [blame]936 encodes debugging information for the variable <tt>X</tt>. The metadata
937 <tt>!dbg !7</tt> attached to the intrinsic provides scope information for the
938 variable <tt>X</tt>.</p>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]939
Bill Wendling991b84e2009-12-01 00:53:11 +0000[diff] [blame]940<div class="doc_code">
941<pre>
942!7 = metadata !{i32 2, i32 7, metadata !1, null}
943!1 = metadata !{i32 458763, metadata !2}; [DW_TAG_lexical_block ]
944!2 = metadata !{i32 458798, i32 0, metadata !3, metadata !"foo",
945 metadata !"foo", metadata !"foo", metadata !3, i32 1,
946 metadata !4, i1 false, i1 true}; [DW_TAG_subprogram ]
947</pre>
948</div>
949
950<p>Here <tt>!7</tt> is metadata providing location information. It has four
951 fields: line number, column number, scope, and original scope. The original
952 scope represents inline location if this instruction is inlined inside a
953 caller, and is null otherwise. In this example, scope is encoded by
Devang Patel4da997b2009-11-25 23:28:01 +0000[diff] [blame]954 <tt>!1</tt>. <tt>!1</tt> represents a lexical block inside the scope
955 <tt>!2</tt>, where <tt>!2</tt> is a
Bill Wendling991b84e2009-12-01 00:53:11 +0000[diff] [blame]956 <a href="#format_subprograms">subprogram descriptor</a>. This way the
957 location information attached to the intrinsics indicates that the
958 variable <tt>X</tt> is declared at line number 2 at a function level scope in
959 function <tt>foo</tt>.</p>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]960
Devang Patel4da997b2009-11-25 23:28:01 +0000[diff] [blame]961<p>Now lets take another example.</p>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]962
Bill Wendling991b84e2009-12-01 00:53:11 +0000[diff] [blame]963<div class="doc_code">
Bill Wendling05252352009-12-01 00:59:58 +0000[diff] [blame]964<pre>
Devang Patel7846c1e2011-02-03 00:22:17 +0000[diff] [blame]965call void @llvm.dbg.declare(metadata, metadata !12), !dbg !14
Bill Wendling991b84e2009-12-01 00:53:11 +0000[diff] [blame]966</pre>
967</div>
968
969<p>The second intrinsic
Devang Patel4da997b2009-11-25 23:28:01 +0000[diff] [blame]970 <tt>%<a href="#format_common_declare">llvm.dbg.declare</a></tt>
Bill Wendling991b84e2009-12-01 00:53:11 +0000[diff] [blame]971 encodes debugging information for variable <tt>Z</tt>. The metadata
972 <tt>!dbg !14</tt> attached to the intrinsic provides scope information for
973 the variable <tt>Z</tt>.</p>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]974
Bill Wendling991b84e2009-12-01 00:53:11 +0000[diff] [blame]975<div class="doc_code">
976<pre>
977!13 = metadata !{i32 458763, metadata !1}; [DW_TAG_lexical_block ]
978!14 = metadata !{i32 5, i32 9, metadata !13, null}
979</pre>
980</div>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]981
John Criswell2a4b0802010-03-17 15:01:50 +0000[diff] [blame]982<p>Here <tt>!14</tt> indicates that <tt>Z</tt> is declared at line number 5 and
Bill Wendling991b84e2009-12-01 00:53:11 +0000[diff] [blame]983 column number 9 inside of lexical scope <tt>!13</tt>. The lexical scope
984 itself resides inside of lexical scope <tt>!1</tt> described above.</p>
985
986<p>The scope information attached with each instruction provides a
987 straightforward way to find instructions covered by a scope.</p>
988
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]989</div>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]990
991<!-- *********************************************************************** -->
992<div class="doc_section">
Chris Lattner941515c2004-01-06 05:31:32 +0000[diff] [blame]993 <a name="ccxx_frontend">C/C++ front-end specific debug information</a>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]994</div>
Misha Brukmancda6a9b2004-12-09 20:27:37 +0000[diff] [blame]995<!-- *********************************************************************** -->
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]996
997<div class="doc_text">
998
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]999<p>The C and C++ front-ends represent information about the program in a format
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1000 that is effectively identical
1001 to <a href="http://www.eagercon.com/dwarf/dwarf3std.htm">DWARF 3.0</a> in
1002 terms of information content. This allows code generators to trivially
1003 support native debuggers by generating standard dwarf information, and
1004 contains enough information for non-dwarf targets to translate it as
1005 needed.</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]1006
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1007<p>This section describes the forms used to represent C and C++ programs. Other
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1008 languages could pattern themselves after this (which itself is tuned to
1009 representing programs in the same way that DWARF 3 does), or they could
1010 choose to provide completely different forms if they don't fit into the DWARF
1011 model. As support for debugging information gets added to the various LLVM
1012 source-language front-ends, the information used should be documented
1013 here.</p>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]1014
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1015<p>The following sections provide examples of various C/C++ constructs and the
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1016 debug information that would best describe those constructs.</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1017
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]1018</div>
1019
1020<!-- ======================================================================= -->
1021<div class="doc_subsection">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1022 <a name="ccxx_compile_units">C/C++ source file information</a>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]1023</div>
1024
1025<div class="doc_text">
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]1026
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1027<p>Given the source files <tt>MySource.cpp</tt> and <tt>MyHeader.h</tt> located
1028 in the directory <tt>/Users/mine/sources</tt>, the following code:</p>
Chris Lattner941515c2004-01-06 05:31:32 +0000[diff] [blame]1029
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1030<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1031<pre>
1032#include "MyHeader.h"
Chris Lattner941515c2004-01-06 05:31:32 +0000[diff] [blame]1033
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1034int main(int argc, char *argv[]) {
1035 return 0;
1036}
1037</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1038</div>
Chris Lattner941515c2004-01-06 05:31:32 +0000[diff] [blame]1039
Misha Brukman39dcddf2008-12-16 02:54:22 +0000[diff] [blame]1040<p>a C/C++ front-end would generate the following descriptors:</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1041
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1042<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1043<pre>
1044...
1045;;
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1046;; Define the compile unit for the main source file "/Users/mine/sources/MySource.cpp".
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1047;;
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1048!2 = metadata !{
1049 i32 524305, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1050 i32 0, ;; Unused
1051 i32 4, ;; Language Id
1052 metadata !"MySource.cpp",
1053 metadata !"/Users/mine/sources",
1054 metadata !"4.2.1 (Based on Apple Inc. build 5649) (LLVM build 00)",
1055 i1 true, ;; Main Compile Unit
1056 i1 false, ;; Optimized compile unit
1057 metadata !"", ;; Compiler flags
1058 i32 0} ;; Runtime version
1059
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1060;;
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1061;; Define the file for the file "/Users/mine/sources/MySource.cpp".
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1062;;
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1063!1 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1064 i32 524329, ;; Tag
1065 metadata !"MySource.cpp",
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1066 metadata !"/Users/mine/sources",
Devang Patel4a7904d62010-07-13 16:53:20 +0000[diff] [blame]1067 metadata !2 ;; Compile unit
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1068}
1069
1070;;
1071;; Define the file for the file "/Users/mine/sources/Myheader.h"
1072;;
1073!3 = metadata !{
1074 i32 524329, ;; Tag
1075 metadata !"Myheader.h"
1076 metadata !"/Users/mine/sources",
Devang Patel4a7904d62010-07-13 16:53:20 +0000[diff] [blame]1077 metadata !2 ;; Compile unit
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1078}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1079
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1080...
1081</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1082</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1083
Devang Patel5bc1c4b2010-03-26 19:08:36 +0000[diff] [blame]1084<p>llvm::Instruction provides easy access to metadata attached with an
1085instruction. One can extract line number information encoded in LLVM IR
1086using <tt>Instruction::getMetadata()</tt> and
1087<tt>DILocation::getLineNumber()</tt>.
1088<pre>
1089 if (MDNode *N = I->getMetadata("dbg")) { // Here I is an LLVM instruction
1090 DILocation Loc(N); // DILocation is in DebugInfo.h
1091 unsigned Line = Loc.getLineNumber();
1092 StringRef File = Loc.getFilename();
1093 StringRef Dir = Loc.getDirectory();
1094 }
1095</pre>
Chris Lattner941515c2004-01-06 05:31:32 +0000[diff] [blame]1096</div>
1097
1098<!-- ======================================================================= -->
1099<div class="doc_subsection">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1100 <a name="ccxx_global_variable">C/C++ global variable information</a>
Chris Lattner941515c2004-01-06 05:31:32 +0000[diff] [blame]1101</div>
1102
1103<div class="doc_text">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1104
Misha Brukman39dcddf2008-12-16 02:54:22 +0000[diff] [blame]1105<p>Given an integer global variable declared as follows:</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1106
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1107<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1108<pre>
1109int MyGlobal = 100;
1110</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1111</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1112
Misha Brukman39dcddf2008-12-16 02:54:22 +0000[diff] [blame]1113<p>a C/C++ front-end would generate the following descriptors:</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1114
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1115<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1116<pre>
1117;;
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1118;; Define the global itself.
1119;;
1120%MyGlobal = global int 100
1121...
1122;;
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1123;; List of debug info of globals
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1124;;
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1125!llvm.dbg.gv = !{!0}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1126
1127;;
1128;; Define the global variable descriptor. Note the reference to the global
1129;; variable anchor and the global variable itself.
1130;;
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1131!0 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1132 i32 524340, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1133 i32 0, ;; Unused
1134 metadata !1, ;; Context
1135 metadata !"MyGlobal", ;; Name
1136 metadata !"MyGlobal", ;; Display Name
1137 metadata !"MyGlobal", ;; Linkage Name
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1138 metadata !3, ;; Compile Unit
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1139 i32 1, ;; Line Number
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1140 metadata !4, ;; Type
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1141 i1 false, ;; Is a local variable
1142 i1 true, ;; Is this a definition
1143 i32* @MyGlobal ;; The global variable
1144}
1145
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1146;;
1147;; Define the basic type of 32 bit signed integer. Note that since int is an
1148;; intrinsic type the source file is NULL and line 0.
1149;;
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1150!4 = metadata !{
1151 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1152 metadata !1, ;; Context
1153 metadata !"int", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1154 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1155 i32 0, ;; Line number
1156 i64 32, ;; Size in Bits
1157 i64 32, ;; Align in Bits
1158 i64 0, ;; Offset in Bits
1159 i32 0, ;; Flags
1160 i32 5 ;; Encoding
1161}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1162
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1163</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1164</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1165
Chris Lattner941515c2004-01-06 05:31:32 +0000[diff] [blame]1166</div>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]1167
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1168<!-- ======================================================================= -->
1169<div class="doc_subsection">
1170 <a name="ccxx_subprogram">C/C++ function information</a>
1171</div>
1172
1173<div class="doc_text">
1174
Misha Brukman39dcddf2008-12-16 02:54:22 +0000[diff] [blame]1175<p>Given a function declared as follows:</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1176
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1177<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1178<pre>
1179int main(int argc, char *argv[]) {
1180 return 0;
1181}
1182</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1183</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1184
Misha Brukman39dcddf2008-12-16 02:54:22 +0000[diff] [blame]1185<p>a C/C++ front-end would generate the following descriptors:</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1186
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1187<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1188<pre>
1189;;
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1190;; Define the anchor for subprograms. Note that the second field of the
1191;; anchor is 46, which is the same as the tag for subprograms
1192;; (46 = DW_TAG_subprogram.)
1193;;
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1194!6 = metadata !{
1195 i32 524334, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1196 i32 0, ;; Unused
1197 metadata !1, ;; Context
1198 metadata !"main", ;; Name
1199 metadata !"main", ;; Display name
1200 metadata !"main", ;; Linkage name
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1201 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1202 i32 1, ;; Line number
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1203 metadata !4, ;; Type
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1204 i1 false, ;; Is local
Devang Patel9f738842011-04-05 22:52:06 +0000[diff] [blame]1205 i1 true, ;; Is definition
1206 i32 0, ;; Virtuality attribute, e.g. pure virtual function
1207 i32 0, ;; Index into virtual table for C++ methods
1208 i32 0, ;; Type that holds virtual table.
1209 i32 0, ;; Flags
1210 i1 false, ;; True if this function is optimized
1211 Function *, ;; Pointer to llvm::Function
1212 null ;; Function template parameters
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1213}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1214;;
1215;; Define the subprogram itself.
1216;;
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1217define i32 @main(i32 %argc, i8** %argv) {
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1218...
1219}
1220</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1221</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1222
1223</div>
1224
1225<!-- ======================================================================= -->
1226<div class="doc_subsection">
1227 <a name="ccxx_basic_types">C/C++ basic types</a>
1228</div>
1229
1230<div class="doc_text">
1231
Misha Brukman39dcddf2008-12-16 02:54:22 +0000[diff] [blame]1232<p>The following are the basic type descriptors for C/C++ core types:</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1233
1234</div>
1235
1236<!-- ======================================================================= -->
1237<div class="doc_subsubsection">
1238 <a name="ccxx_basic_type_bool">bool</a>
1239</div>
1240
1241<div class="doc_text">
1242
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1243<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1244<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1245!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1246 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1247 metadata !1, ;; Context
1248 metadata !"bool", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1249 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1250 i32 0, ;; Line number
1251 i64 8, ;; Size in Bits
1252 i64 8, ;; Align in Bits
1253 i64 0, ;; Offset in Bits
1254 i32 0, ;; Flags
1255 i32 2 ;; Encoding
1256}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1257</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1258</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1259
1260</div>
1261
1262<!-- ======================================================================= -->
1263<div class="doc_subsubsection">
1264 <a name="ccxx_basic_char">char</a>
1265</div>
1266
1267<div class="doc_text">
1268
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1269<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1270<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1271!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1272 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1273 metadata !1, ;; Context
1274 metadata !"char", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1275 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1276 i32 0, ;; Line number
1277 i64 8, ;; Size in Bits
1278 i64 8, ;; Align in Bits
1279 i64 0, ;; Offset in Bits
1280 i32 0, ;; Flags
1281 i32 6 ;; Encoding
1282}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1283</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1284</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1285
1286</div>
1287
1288<!-- ======================================================================= -->
1289<div class="doc_subsubsection">
1290 <a name="ccxx_basic_unsigned_char">unsigned char</a>
1291</div>
1292
1293<div class="doc_text">
1294
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1295<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1296<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1297!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1298 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1299 metadata !1, ;; Context
1300 metadata !"unsigned char",
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1301 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1302 i32 0, ;; Line number
1303 i64 8, ;; Size in Bits
1304 i64 8, ;; Align in Bits
1305 i64 0, ;; Offset in Bits
1306 i32 0, ;; Flags
1307 i32 8 ;; Encoding
1308}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1309</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1310</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1311
1312</div>
1313
1314<!-- ======================================================================= -->
1315<div class="doc_subsubsection">
1316 <a name="ccxx_basic_short">short</a>
1317</div>
1318
1319<div class="doc_text">
1320
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1321<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1322<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1323!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1324 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1325 metadata !1, ;; Context
1326 metadata !"short int",
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1327 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1328 i32 0, ;; Line number
1329 i64 16, ;; Size in Bits
1330 i64 16, ;; Align in Bits
1331 i64 0, ;; Offset in Bits
1332 i32 0, ;; Flags
1333 i32 5 ;; Encoding
1334}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1335</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1336</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1337
1338</div>
1339
1340<!-- ======================================================================= -->
1341<div class="doc_subsubsection">
1342 <a name="ccxx_basic_unsigned_short">unsigned short</a>
1343</div>
1344
1345<div class="doc_text">
1346
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1347<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1348<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1349!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1350 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1351 metadata !1, ;; Context
1352 metadata !"short unsigned int",
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1353 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1354 i32 0, ;; Line number
1355 i64 16, ;; Size in Bits
1356 i64 16, ;; Align in Bits
1357 i64 0, ;; Offset in Bits
1358 i32 0, ;; Flags
1359 i32 7 ;; Encoding
1360}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1361</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1362</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1363
1364</div>
1365
1366<!-- ======================================================================= -->
1367<div class="doc_subsubsection">
1368 <a name="ccxx_basic_int">int</a>
1369</div>
1370
1371<div class="doc_text">
1372
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1373<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1374<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1375!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1376 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1377 metadata !1, ;; Context
1378 metadata !"int", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1379 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1380 i32 0, ;; Line number
1381 i64 32, ;; Size in Bits
1382 i64 32, ;; Align in Bits
1383 i64 0, ;; Offset in Bits
1384 i32 0, ;; Flags
1385 i32 5 ;; Encoding
1386}
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1387</pre></div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1388
1389</div>
1390
1391<!-- ======================================================================= -->
1392<div class="doc_subsubsection">
1393 <a name="ccxx_basic_unsigned_int">unsigned int</a>
1394</div>
1395
1396<div class="doc_text">
1397
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1398<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1399<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1400!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1401 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1402 metadata !1, ;; Context
1403 metadata !"unsigned int",
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1404 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1405 i32 0, ;; Line number
1406 i64 32, ;; Size in Bits
1407 i64 32, ;; Align in Bits
1408 i64 0, ;; Offset in Bits
1409 i32 0, ;; Flags
1410 i32 7 ;; Encoding
1411}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1412</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1413</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1414
1415</div>
1416
1417<!-- ======================================================================= -->
1418<div class="doc_subsubsection">
1419 <a name="ccxx_basic_long_long">long long</a>
1420</div>
1421
1422<div class="doc_text">
1423
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1424<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1425<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1426!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1427 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1428 metadata !1, ;; Context
1429 metadata !"long long int",
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1430 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1431 i32 0, ;; Line number
1432 i64 64, ;; Size in Bits
1433 i64 64, ;; Align in Bits
1434 i64 0, ;; Offset in Bits
1435 i32 0, ;; Flags
1436 i32 5 ;; Encoding
1437}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1438</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1439</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1440
1441</div>
1442
1443<!-- ======================================================================= -->
1444<div class="doc_subsubsection">
1445 <a name="ccxx_basic_unsigned_long_long">unsigned long long</a>
1446</div>
1447
1448<div class="doc_text">
1449
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1450<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1451<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1452!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1453 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1454 metadata !1, ;; Context
1455 metadata !"long long unsigned int",
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1456 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1457 i32 0, ;; Line number
1458 i64 64, ;; Size in Bits
1459 i64 64, ;; Align in Bits
1460 i64 0, ;; Offset in Bits
1461 i32 0, ;; Flags
1462 i32 7 ;; Encoding
1463}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1464</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1465</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1466
1467</div>
1468
1469<!-- ======================================================================= -->
1470<div class="doc_subsubsection">
1471 <a name="ccxx_basic_float">float</a>
1472</div>
1473
1474<div class="doc_text">
1475
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1476<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1477<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1478!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1479 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1480 metadata !1, ;; Context
1481 metadata !"float",
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1482 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1483 i32 0, ;; Line number
1484 i64 32, ;; Size in Bits
1485 i64 32, ;; Align in Bits
1486 i64 0, ;; Offset in Bits
1487 i32 0, ;; Flags
1488 i32 4 ;; Encoding
1489}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1490</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1491</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1492
1493</div>
1494
1495<!-- ======================================================================= -->
1496<div class="doc_subsubsection">
1497 <a name="ccxx_basic_double">double</a>
1498</div>
1499
1500<div class="doc_text">
1501
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1502<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1503<pre>
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1504!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1505 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1506 metadata !1, ;; Context
1507 metadata !"double",;; Name
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1508 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1509 i32 0, ;; Line number
1510 i64 64, ;; Size in Bits
1511 i64 64, ;; Align in Bits
1512 i64 0, ;; Offset in Bits
1513 i32 0, ;; Flags
1514 i32 4 ;; Encoding
1515}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1516</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1517</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1518
1519</div>
1520
1521<!-- ======================================================================= -->
1522<div class="doc_subsection">
1523 <a name="ccxx_derived_types">C/C++ derived types</a>
1524</div>
1525
1526<div class="doc_text">
1527
Misha Brukman39dcddf2008-12-16 02:54:22 +0000[diff] [blame]1528<p>Given the following as an example of C/C++ derived type:</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1529
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1530<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1531<pre>
1532typedef const int *IntPtr;
1533</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1534</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1535
Misha Brukman39dcddf2008-12-16 02:54:22 +0000[diff] [blame]1536<p>a C/C++ front-end would generate the following descriptors:</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1537
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1538<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1539<pre>
1540;;
1541;; Define the typedef "IntPtr".
1542;;
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1543!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1544 i32 524310, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1545 metadata !1, ;; Context
1546 metadata !"IntPtr", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1547 metadata !3, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1548 i32 0, ;; Line number
1549 i64 0, ;; Size in bits
1550 i64 0, ;; Align in bits
1551 i64 0, ;; Offset in bits
1552 i32 0, ;; Flags
1553 metadata !4 ;; Derived From type
1554}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1555
1556;;
1557;; Define the pointer type.
1558;;
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1559!4 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1560 i32 524303, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1561 metadata !1, ;; Context
1562 metadata !"", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1563 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1564 i32 0, ;; Line number
1565 i64 64, ;; Size in bits
1566 i64 64, ;; Align in bits
1567 i64 0, ;; Offset in bits
1568 i32 0, ;; Flags
1569 metadata !5 ;; Derived From type
1570}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1571;;
1572;; Define the const type.
1573;;
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1574!5 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1575 i32 524326, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1576 metadata !1, ;; Context
1577 metadata !"", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1578 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1579 i32 0, ;; Line number
1580 i64 32, ;; Size in bits
1581 i64 32, ;; Align in bits
1582 i64 0, ;; Offset in bits
1583 i32 0, ;; Flags
1584 metadata !6 ;; Derived From type
1585}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1586;;
1587;; Define the int type.
1588;;
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1589!6 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1590 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1591 metadata !1, ;; Context
1592 metadata !"int", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1593 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1594 i32 0, ;; Line number
1595 i64 32, ;; Size in bits
1596 i64 32, ;; Align in bits
1597 i64 0, ;; Offset in bits
1598 i32 0, ;; Flags
1599 5 ;; Encoding
1600}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1601</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1602</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1603
1604</div>
1605
1606<!-- ======================================================================= -->
1607<div class="doc_subsection">
1608 <a name="ccxx_composite_types">C/C++ struct/union types</a>
1609</div>
1610
1611<div class="doc_text">
1612
Misha Brukman39dcddf2008-12-16 02:54:22 +0000[diff] [blame]1613<p>Given the following as an example of C/C++ struct type:</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1614
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1615<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1616<pre>
1617struct Color {
1618 unsigned Red;
1619 unsigned Green;
1620 unsigned Blue;
1621};
1622</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1623</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1624
Misha Brukman39dcddf2008-12-16 02:54:22 +0000[diff] [blame]1625<p>a C/C++ front-end would generate the following descriptors:</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1626
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1627<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1628<pre>
1629;;
1630;; Define basic type for unsigned int.
1631;;
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1632!5 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1633 i32 524324, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1634 metadata !1, ;; Context
1635 metadata !"unsigned int",
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1636 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1637 i32 0, ;; Line number
1638 i64 32, ;; Size in Bits
1639 i64 32, ;; Align in Bits
1640 i64 0, ;; Offset in Bits
1641 i32 0, ;; Flags
1642 i32 7 ;; Encoding
1643}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1644;;
1645;; Define composite type for struct Color.
1646;;
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1647!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1648 i32 524307, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1649 metadata !1, ;; Context
1650 metadata !"Color", ;; Name
1651 metadata !1, ;; Compile unit
1652 i32 1, ;; Line number
1653 i64 96, ;; Size in bits
1654 i64 32, ;; Align in bits
1655 i64 0, ;; Offset in bits
1656 i32 0, ;; Flags
1657 null, ;; Derived From
1658 metadata !3, ;; Elements
1659 i32 0 ;; Runtime Language
1660}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1661
1662;;
1663;; Define the Red field.
1664;;
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1665!4 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1666 i32 524301, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1667 metadata !1, ;; Context
1668 metadata !"Red", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1669 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1670 i32 2, ;; Line number
1671 i64 32, ;; Size in bits
1672 i64 32, ;; Align in bits
1673 i64 0, ;; Offset in bits
1674 i32 0, ;; Flags
1675 metadata !5 ;; Derived From type
1676}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1677
1678;;
1679;; Define the Green field.
1680;;
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1681!6 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1682 i32 524301, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1683 metadata !1, ;; Context
1684 metadata !"Green", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1685 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1686 i32 3, ;; Line number
1687 i64 32, ;; Size in bits
1688 i64 32, ;; Align in bits
1689 i64 32, ;; Offset in bits
1690 i32 0, ;; Flags
1691 metadata !5 ;; Derived From type
1692}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1693
1694;;
1695;; Define the Blue field.
1696;;
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1697!7 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1698 i32 524301, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1699 metadata !1, ;; Context
1700 metadata !"Blue", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1701 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1702 i32 4, ;; Line number
1703 i64 32, ;; Size in bits
1704 i64 32, ;; Align in bits
1705 i64 64, ;; Offset in bits
1706 i32 0, ;; Flags
1707 metadata !5 ;; Derived From type
1708}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1709
1710;;
1711;; Define the array of fields used by the composite type Color.
1712;;
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1713!3 = metadata !{metadata !4, metadata !6, metadata !7}
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1714</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1715</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1716
1717</div>
1718
1719<!-- ======================================================================= -->
1720<div class="doc_subsection">
1721 <a name="ccxx_enumeration_types">C/C++ enumeration types</a>
1722</div>
1723
1724<div class="doc_text">
1725
Misha Brukman39dcddf2008-12-16 02:54:22 +0000[diff] [blame]1726<p>Given the following as an example of C/C++ enumeration type:</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1727
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1728<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1729<pre>
1730enum Trees {
1731 Spruce = 100,
1732 Oak = 200,
1733 Maple = 300
1734};
1735</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1736</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1737
Misha Brukman39dcddf2008-12-16 02:54:22 +0000[diff] [blame]1738<p>a C/C++ front-end would generate the following descriptors:</p>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1739
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1740<div class="doc_code">
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1741<pre>
1742;;
1743;; Define composite type for enum Trees
1744;;
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1745!2 = metadata !{
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1746 i32 524292, ;; Tag
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1747 metadata !1, ;; Context
1748 metadata !"Trees", ;; Name
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1749 metadata !1, ;; File
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1750 i32 1, ;; Line number
1751 i64 32, ;; Size in bits
1752 i64 32, ;; Align in bits
1753 i64 0, ;; Offset in bits
1754 i32 0, ;; Flags
1755 null, ;; Derived From type
1756 metadata !3, ;; Elements
1757 i32 0 ;; Runtime language
1758}
Devang Patel02aac922009-08-25 05:24:07 +0000[diff] [blame]1759
Devang Patelf08e35d2009-08-26 05:01:18 +0000[diff] [blame]1760;;
1761;; Define the array of enumerators used by composite type Trees.
1762;;
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1763!3 = metadata !{metadata !4, metadata !5, metadata !6}
1764
1765;;
1766;; Define Spruce enumerator.
1767;;
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1768!4 = metadata !{i32 524328, metadata !"Spruce", i64 100}
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1769
1770;;
1771;; Define Oak enumerator.
1772;;
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1773!5 = metadata !{i32 524328, metadata !"Oak", i64 200}
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1774
1775;;
1776;; Define Maple enumerator.
1777;;
Devang Patel59445db2010-03-09 00:44:10 +0000[diff] [blame]1778!6 = metadata !{i32 524328, metadata !"Maple", i64 300}
Devang Patel80ae3492009-08-28 23:24:31 +0000[diff] [blame]1779
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1780</pre>
Bill Wendlinge9353d72009-05-17 05:52:39 +0000[diff] [blame]1781</div>
Jim Laskey14edc932006-03-14 18:08:46 +0000[diff] [blame]1782
1783</div>
Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]1784
1785<!-- *********************************************************************** -->
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Chris Lattner1811fca2004-01-05 05:06:33 +0000[diff] [blame]1787<hr>
Misha Brukmanf91d9942004-05-12 19:21:57 +0000[diff] [blame]1788<address>
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1794 <a href="mailto:sabre@nondot.org">Chris Lattner</a><br>
NAKAMURA Takumica46f5a2011-04-09 02:13:37 +0000[diff] [blame^]1795 <a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br>
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