| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 1 | <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" | 
|  | 2 | "http://www.w3.org/TR/html4/strict.dtd"> | 
|  | 3 | <html> | 
|  | 4 | <head> | 
|  | 5 | <link rel="stylesheet" href="llvm.css" type="text/css"> | 
| Chris Lattner | 1a7e43c | 2004-04-01 00:41:31 +0000 | [diff] [blame] | 6 | <title>LLVM 1.3 Release Notes</title> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 7 | </head> | 
|  | 8 | <body> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 9 |  | 
| Chris Lattner | 1a7e43c | 2004-04-01 00:41:31 +0000 | [diff] [blame] | 10 | <div class="doc_title">LLVM 1.3 Release Notes</div> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 11 |  | 
|  | 12 | <ol> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 13 | <li><a href="#intro">Introduction</a></li> | 
|  | 14 | <li><a href="#whatsnew">What's New?</a></li> | 
| Chris Lattner | 77a5173 | 2004-04-30 22:17:12 +0000 | [diff] [blame] | 15 | <li><a href="GettingStarted.html">Installation Instructions</a></li> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 16 | <li><a href="#portability">Portability and Supported Platforms</a></li> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 17 | <li><a href="#knownproblems">Known Problems</a> | 
|  | 18 | <ul> | 
| Chris Lattner | 1a7e43c | 2004-04-01 00:41:31 +0000 | [diff] [blame] | 19 | <li><a href="#experimental">Experimental features included in this | 
|  | 20 | release</a> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 21 | <li><a href="#core">Known problems with the LLVM Core</a> | 
|  | 22 | <li><a href="#c-fe">Known problems with the C Front-end</a> | 
|  | 23 | <li><a href="#c++-fe">Known problems with the C++ Front-end</a> | 
|  | 24 | <li><a href="#x86-be">Known problems with the X86 Back-end</a> | 
|  | 25 | <li><a href="#sparc-be">Known problems with the Sparc Back-end</a> | 
|  | 26 | <li><a href="#c-be">Known problems with the C back-end</a> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 27 | </ul></li> | 
|  | 28 | <li><a href="#additionalinfo">Additional Information</a></li> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 29 | </ol> | 
|  | 30 |  | 
| Chris Lattner | 020e1fc | 2004-05-23 21:07:27 +0000 | [diff] [blame] | 31 | <div class="doc_author"> | 
|  | 32 | <p>Written by the <a href="http://llvm.cs.uiuc.edu">LLVM team</a><p> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 33 | </div> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 34 |  | 
|  | 35 | <!-- *********************************************************************** --> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 36 | <div class="doc_section"> | 
|  | 37 | <a name="intro">Introduction</a> | 
|  | 38 | </div> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 39 | <!-- *********************************************************************** --> | 
|  | 40 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 41 | <div class="doc_text"> | 
|  | 42 |  | 
|  | 43 | <p>This document contains the release notes for the LLVM compiler | 
| Chris Lattner | 1a7e43c | 2004-04-01 00:41:31 +0000 | [diff] [blame] | 44 | infrastructure, release 1.3.  Here we describe the status of LLVM, including any | 
| John Criswell | 86a3a48 | 2003-12-18 16:43:17 +0000 | [diff] [blame] | 45 | known problems and bug fixes from the previous release.  The most up-to-date | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 46 | version of this document can be found on the <a | 
| Chris Lattner | 1a7e43c | 2004-04-01 00:41:31 +0000 | [diff] [blame] | 47 | href="http://llvm.cs.uiuc.edu/releases/1.3/">LLVM 1.3 web site</a>.  If you are | 
| John Criswell | 86a3a48 | 2003-12-18 16:43:17 +0000 | [diff] [blame] | 48 | not reading this on the LLVM web pages, you should probably go there because | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 49 | this document may be updated after the release.</p> | 
| Chris Lattner | 6249576 | 2003-10-02 16:38:05 +0000 | [diff] [blame] | 50 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 51 | <p>For more information about LLVM, including information about potentially more | 
| Chris Lattner | e7525b5 | 2003-10-07 21:38:31 +0000 | [diff] [blame] | 52 | current releases, please check out the <a href="http://llvm.cs.uiuc.edu">main | 
|  | 53 | web site</a>.  If you have questions or comments, the <a | 
|  | 54 | href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM developer's mailing | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 55 | list</a> is a good place to send them.</p> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 56 |  | 
| Chris Lattner | e76e9ab | 2003-12-12 04:25:33 +0000 | [diff] [blame] | 57 | <p>Note that if you are reading this file from CVS, this document applies | 
|  | 58 | to the <i>next</i> release, not the current one.  To see the release notes for | 
|  | 59 | the current or previous releases, see the <a | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 60 | href="http://llvm.cs.uiuc.edu/releases/">releases page</a>.</p> | 
|  | 61 |  | 
|  | 62 | </div> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 63 |  | 
|  | 64 | <!-- *********************************************************************** --> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 65 | <div class="doc_section"> | 
|  | 66 | <a name="whatsnew">What's New?</a> | 
|  | 67 | </div> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 68 | <!-- *********************************************************************** --> | 
|  | 69 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 70 | <div class="doc_text"> | 
|  | 71 |  | 
| Misha Brukman | fa50a22 | 2004-05-12 21:46:05 +0000 | [diff] [blame] | 72 | <p>This is the fourth public release of the LLVM compiler infrastructure.  This | 
| Chris Lattner | ea309ff | 2004-05-04 17:04:09 +0000 | [diff] [blame] | 73 | release primarily improves the <a href="#codequality">performance of the | 
| Chris Lattner | b7c4bac | 2004-06-18 06:26:29 +0000 | [diff] [blame] | 74 | code</a> produced by all aspects of the LLVM compiler and adds many <a | 
|  | 75 | href="#newfeatures">new features</a>, and <a href="#bugfix">fixes a few | 
| Misha Brukman | fa50a22 | 2004-05-12 21:46:05 +0000 | [diff] [blame] | 76 | bugs</a> as well.</p> | 
| Chris Lattner | ba7bd47 | 2003-12-06 20:22:41 +0000 | [diff] [blame] | 77 |  | 
| Misha Brukman | fa50a22 | 2004-05-12 21:46:05 +0000 | [diff] [blame] | 78 | <p> At this time, LLVM is known to correctly compile and run all C & C++ | 
|  | 79 | SPEC CPU2000 benchmarks, the Olden benchmarks, and the Ptrdist benchmarks.  It | 
|  | 80 | has also been used to compile <b>many</b> other programs.  LLVM now also works | 
|  | 81 | with a broad variety of C++ programs, though it has still received less testing | 
|  | 82 | than the C front-end.</p> | 
| Chris Lattner | ba7bd47 | 2003-12-06 20:22:41 +0000 | [diff] [blame] | 83 |  | 
| Chris Lattner | 21a9040 | 2004-05-24 04:50:25 +0000 | [diff] [blame] | 84 | </div> | 
|  | 85 |  | 
| Chris Lattner | ba7bd47 | 2003-12-06 20:22:41 +0000 | [diff] [blame] | 86 | <!--=========================================================================--> | 
|  | 87 | <div class="doc_subsubsection"> | 
| Chris Lattner | 8ebf253 | 2004-02-25 16:36:51 +0000 | [diff] [blame] | 88 | <a name="newfeatures">This release implements the following new features:</a> | 
| Chris Lattner | ba7bd47 | 2003-12-06 20:22:41 +0000 | [diff] [blame] | 89 | </div> | 
| Chris Lattner | e7525b5 | 2003-10-07 21:38:31 +0000 | [diff] [blame] | 90 |  | 
| Chris Lattner | 21a9040 | 2004-05-24 04:50:25 +0000 | [diff] [blame] | 91 | <div class="doc_text"> | 
|  | 92 |  | 
| Chris Lattner | e7525b5 | 2003-10-07 21:38:31 +0000 | [diff] [blame] | 93 | <ol> | 
| Chris Lattner | 1a7e43c | 2004-04-01 00:41:31 +0000 | [diff] [blame] | 94 | <li>The LLVM <a href="LangRef.html#i_select"><tt>select</tt></a> instruction is | 
| Chris Lattner | 2ad4878 | 2004-05-02 04:19:15 +0000 | [diff] [blame] | 95 | now fully implemented and supported by all transformations, native code | 
|  | 96 | generators, and the interpreter.</li> | 
| Misha Brukman | 017f2f3 | 2004-04-19 02:56:49 +0000 | [diff] [blame] | 97 | <li>Bugpoint can now narrow down code-generation bugs to a loop nest, where | 
|  | 98 | before it could only narrow them down to a function being miscompiled.</li> | 
| Brian Gaeke | e307f8a7 | 2004-05-04 21:22:57 +0000 | [diff] [blame] | 99 | <li><a href="http://llvm.cs.uiuc.edu/PR40">Bugpoint can now debug arbitrary | 
|  | 100 | modes of llc</a> and lli, by passing them command line flags (e.g., | 
|  | 101 | <tt>-regalloc=linearscan</tt>, <tt>-enable-correct-eh-support</tt>, etc.) </li> | 
| Chris Lattner | 2ad4878 | 2004-05-02 04:19:15 +0000 | [diff] [blame] | 102 | <li>The Control Flow Graph in the native code generators is no longer | 
|  | 103 | constrained to be the same as the CFG for the LLVM input code.</li> | 
|  | 104 | <li>The LLVM induction variable analysis routines have been rewritten.</li> | 
|  | 105 | <li>LLVM now has new loop unrolling and loop unswitching passes.</li> | 
|  | 106 | <li>The induction variable substitution pass performs linear function test | 
|  | 107 | replacement and exit value replacement optimizations.</li> | 
| Chris Lattner | eda4f47 | 2004-05-24 04:45:52 +0000 | [diff] [blame] | 108 | <li>LLVM now has first-class support for <a href="GarbageCollection.html">Accurate | 
|  | 109 | Garbage Collection</a>, enabling the use of aggressive copying and generational | 
|  | 110 | collectors.</li> | 
|  | 111 | <li>LLVM now includes an implementation of Andersen's interprocedural alias | 
|  | 112 | analysis algorithm.</li> | 
| Chris Lattner | 57e7a4c | 2004-05-24 05:34:32 +0000 | [diff] [blame] | 113 | <li>Bugpoint can <a href="http://llvm.cs.uiuc.edu/PR327">extract individual | 
|  | 114 | basic blocks</a> to track down reduce miscompilation testcases.</li> | 
| Brian Gaeke | 84c8bd0 | 2004-06-01 20:02:56 +0000 | [diff] [blame] | 115 | <li>LLVM and the C front-end now work under Win32 using the | 
|  | 116 | <a href="http://www.cygwin.com">Cygwin</a> runtime libraries. | 
| Chris Lattner | 2c7b087 | 2004-06-01 18:22:41 +0000 | [diff] [blame] | 117 | This includes the JIT compiler.</li> | 
| Chris Lattner | a7fac95 | 2004-06-04 00:40:11 +0000 | [diff] [blame] | 118 | <li>The LLVM code generator is now being <a | 
|  | 119 | href="CodeGenerator.html">documented</a>.</li> | 
| Reid Spencer | 850f85f | 2004-06-08 07:30:31 +0000 | [diff] [blame] | 120 | <li>There is a new tool, llvm-abcd, the Analysis of ByteCode Dumper (abcd). | 
|  | 121 | This tool can compute basic statistics and bytecode density statistics on a | 
|  | 122 | module or function basis and also dump out bytecode in a textual format that | 
|  | 123 | is lower level than assembly (values are not resolved from slot numbers). | 
|  | 124 | It should only be of interest to (a) those who are working to improve the | 
|  | 125 | bytecode format and (b) those who really want to understand or document the | 
|  | 126 | details of the bytecode format.</li> | 
|  | 127 | <li>The <a href="BytecodeFormat.html">LLVM Bytecode file format</a> is now | 
|  | 128 | being documented.</li> | 
| Chris Lattner | f64f794 | 2004-06-15 21:50:46 +0000 | [diff] [blame] | 129 | <li>LLVM now provides an <a href="LangRef.html#i_isunordered">llvm.isunordered</a> intrinsic | 
| Chris Lattner | 4e71aa8 | 2004-06-11 04:35:21 +0000 | [diff] [blame] | 130 | for efficient implementation of unordered floating point comparisons.</li> | 
| Chris Lattner | b7c4bac | 2004-06-18 06:26:29 +0000 | [diff] [blame] | 131 | <li>The llvmgcc front-end now supports the GCC builtins for ISO C99 floating | 
|  | 132 | point comparison macros (e.g., <tt>__builtin_islessequal</tt>).</li> | 
| Reid Spencer | 3a4916e | 2004-06-23 06:33:15 +0000 | [diff] [blame] | 133 | <li>Now that there are more source files than can fit on a 32Kbyte command | 
|  | 134 | line (Linux's limit), there's a new utility for searching the sources. The | 
|  | 135 | llvmgrep tool in the utils directory combines an egrep and a find without | 
|  | 136 | passing filenames through the command line. This improves performance | 
|  | 137 | slightly. Simply run llvmgrep like you might egrep but leave off the file | 
|  | 138 | names.</li> | 
| Chris Lattner | 592db40 | 2003-11-19 22:05:38 +0000 | [diff] [blame] | 139 | </ol> | 
| Chris Lattner | 4491de6 | 2003-11-08 04:28:55 +0000 | [diff] [blame] | 140 |  | 
| Chris Lattner | 21a9040 | 2004-05-24 04:50:25 +0000 | [diff] [blame] | 141 | </div> | 
|  | 142 |  | 
| Chris Lattner | ba7bd47 | 2003-12-06 20:22:41 +0000 | [diff] [blame] | 143 |  | 
|  | 144 | <!--=========================================================================--> | 
|  | 145 | <div class="doc_subsubsection"> | 
|  | 146 | In this release, the following missing features were implemented: | 
|  | 147 | </div> | 
| Chris Lattner | 4491de6 | 2003-11-08 04:28:55 +0000 | [diff] [blame] | 148 |  | 
| Chris Lattner | 21a9040 | 2004-05-24 04:50:25 +0000 | [diff] [blame] | 149 | <div class="doc_text"> | 
|  | 150 |  | 
| Chris Lattner | 4491de6 | 2003-11-08 04:28:55 +0000 | [diff] [blame] | 151 | <ol> | 
| Misha Brukman | 017f2f3 | 2004-04-19 02:56:49 +0000 | [diff] [blame] | 152 | <li><a href="http://llvm.cs.uiuc.edu/PR82">LLVM cannot handle structures with | 
|  | 153 | more than 256 elements</a></li> | 
| Misha Brukman | e705023 | 2004-04-19 03:01:01 +0000 | [diff] [blame] | 154 | <li><a href="http://llvm.cs.uiuc.edu/PR38">[bugpoint] External functions used in | 
|  | 155 | non-instruction entities, such as global constant initializer</a></li> | 
| Reid Spencer | 45e25d8 | 2004-05-09 23:32:39 +0000 | [diff] [blame] | 156 | <li><a href="http://llvm.cs.uiuc.edu/PR178">Stacker does not handle targets | 
|  | 157 | with 64-bit pointers.</a></li> | 
| Misha Brukman | e705023 | 2004-04-19 03:01:01 +0000 | [diff] [blame] | 158 | <li><a href="http://llvm.cs.uiuc.edu/PR290">Bugpoint doesn't support | 
|  | 159 | uses of external fns by immediate constant exprs</a></li> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 160 | </ol> | 
| Chris Lattner | e7525b5 | 2003-10-07 21:38:31 +0000 | [diff] [blame] | 161 |  | 
| Chris Lattner | 21a9040 | 2004-05-24 04:50:25 +0000 | [diff] [blame] | 162 | </div> | 
| Chris Lattner | ba7bd47 | 2003-12-06 20:22:41 +0000 | [diff] [blame] | 163 |  | 
|  | 164 | <!--=========================================================================--> | 
|  | 165 | <div class="doc_subsubsection"> | 
| Misha Brukman | 017f2f3 | 2004-04-19 02:56:49 +0000 | [diff] [blame] | 166 | <a name="qualityofimp">In this release, the following Quality of Implementation | 
|  | 167 | issues were fixed:</a> | 
| Chris Lattner | 4df78f0 | 2003-12-20 03:42:11 +0000 | [diff] [blame] | 168 | </div> | 
|  | 169 |  | 
| Chris Lattner | 21a9040 | 2004-05-24 04:50:25 +0000 | [diff] [blame] | 170 | <div class="doc_text"> | 
|  | 171 |  | 
| Chris Lattner | 4df78f0 | 2003-12-20 03:42:11 +0000 | [diff] [blame] | 172 | <ol> | 
| Misha Brukman | 017f2f3 | 2004-04-19 02:56:49 +0000 | [diff] [blame] | 173 | <li><a href="http://llvm.cs.uiuc.edu/PR305">LLVM tools will happily spew | 
|  | 174 | bytecode onto your terminal</a></li> | 
| Misha Brukman | fa50a22 | 2004-05-12 21:46:05 +0000 | [diff] [blame] | 175 | <li><a href="http://llvm.cs.uiuc.edu/PR329">[llvmgcc] type names are not emitted | 
|  | 176 | for structure typedefs</a></li> | 
| Chris Lattner | f10ccbf | 2004-05-24 04:53:32 +0000 | [diff] [blame] | 177 | <li>All documentation is now conformant to the HTML 4.01 (Strict) level.</li> | 
| Chris Lattner | bd948cf | 2004-06-08 07:19:29 +0000 | [diff] [blame] | 178 | <li>The spurious "WARNING: Found global types that are not compatible" warning | 
|  | 179 | produced when linking C++ programs has been fixed.</li> | 
| Chris Lattner | 4df78f0 | 2003-12-20 03:42:11 +0000 | [diff] [blame] | 180 | </ol> | 
|  | 181 |  | 
| Chris Lattner | 21a9040 | 2004-05-24 04:50:25 +0000 | [diff] [blame] | 182 | </div> | 
|  | 183 |  | 
| Chris Lattner | 4df78f0 | 2003-12-20 03:42:11 +0000 | [diff] [blame] | 184 | <!--=========================================================================--> | 
|  | 185 | <div class="doc_subsubsection"> | 
| Chris Lattner | 8ebf253 | 2004-02-25 16:36:51 +0000 | [diff] [blame] | 186 | In this release, the following build problems were fixed: | 
| Brian Gaeke | 8b05e4f | 2004-01-16 21:55:04 +0000 | [diff] [blame] | 187 | </div> | 
|  | 188 |  | 
| Chris Lattner | 21a9040 | 2004-05-24 04:50:25 +0000 | [diff] [blame] | 189 | <div class="doc_text"> | 
| Brian Gaeke | 8b05e4f | 2004-01-16 21:55:04 +0000 | [diff] [blame] | 190 | <ol> | 
| Misha Brukman | fa50a22 | 2004-05-12 21:46:05 +0000 | [diff] [blame] | 191 | <li><a href="http://llvm.cs.uiuc.edu/PR301">Minor configure bugs with | 
|  | 192 | -disable/enable-povray and -disable-spec</a></li> | 
|  | 193 | <li><a href="http://llvm.cs.uiuc.edu/PR289">shell scripts output by gccld don't | 
|  | 194 | work if you change PATH</a></li> | 
| Chris Lattner | 4769612 | 2004-06-09 01:09:16 +0000 | [diff] [blame] | 195 | <li><a href="http://llvm.cs.uiuc.edu/PR364">[llvmgcc] llvmgcc does not compile | 
|  | 196 | with gcc 3.4</a></li> | 
| Chris Lattner | 3daf984 | 2004-06-18 17:57:29 +0000 | [diff] [blame] | 197 | <li><a href="http://llvm.cs.uiuc.edu/PR373">[llvmgcc] obstack.h relies on | 
|  | 198 | obsolete casts-as-lvalues GCC extension</a></li> | 
| Brian Gaeke | 8b05e4f | 2004-01-16 21:55:04 +0000 | [diff] [blame] | 199 | </ol> | 
| Chris Lattner | 21a9040 | 2004-05-24 04:50:25 +0000 | [diff] [blame] | 200 | </div> | 
| Brian Gaeke | 8b05e4f | 2004-01-16 21:55:04 +0000 | [diff] [blame] | 201 |  | 
|  | 202 | <!--=========================================================================--> | 
|  | 203 | <div class="doc_subsubsection"> | 
| Chris Lattner | 2ad4878 | 2004-05-02 04:19:15 +0000 | [diff] [blame] | 204 | <a name="codequality">This release includes the following Code Quality | 
|  | 205 | improvements:</a> | 
| Chris Lattner | 2325706 | 2004-05-23 20:42:08 +0000 | [diff] [blame] | 206 | </div> | 
| Chris Lattner | 639579c | 2003-10-27 17:06:39 +0000 | [diff] [blame] | 207 |  | 
| Chris Lattner | 21a9040 | 2004-05-24 04:50:25 +0000 | [diff] [blame] | 208 | <div class="doc_text"> | 
| Chris Lattner | 639579c | 2003-10-27 17:06:39 +0000 | [diff] [blame] | 209 | <ol> | 
| Chris Lattner | 2ad4878 | 2004-05-02 04:19:15 +0000 | [diff] [blame] | 210 | <li>Fixed: <a href="http://llvm.cs.uiuc.edu/PR309">[vmcore] Code quality problem | 
|  | 211 | due to long operand of getelementptr</a></li> | 
| Chris Lattner | 54dcea8 | 2004-04-13 14:43:35 +0000 | [diff] [blame] | 212 |  | 
|  | 213 | <li>The X86 backend now generates substantially better code for 64-bit integer | 
|  | 214 | and floating point operations.</li> | 
|  | 215 |  | 
|  | 216 | <li>The -inline pass no longer inlines mutually recursive functions until it | 
|  | 217 | hits the inlining threshold.</li> | 
|  | 218 |  | 
|  | 219 | <li>The -inline pass no longer misses obvious inlining opportunities just | 
|  | 220 | because the callee eventually calls into an external function.</li> | 
|  | 221 |  | 
|  | 222 | <li>The -simplifycfg pass can now "if convert" simple statements into the new | 
|  | 223 | <tt>select</tt> instruction.</li> | 
|  | 224 |  | 
|  | 225 | <li>The -loopsimplify pass can now break <a | 
|  | 226 | href="http://llvm.cs.uiuc.edu/PR35">natural loops with multiple backedges</a> | 
|  | 227 | into multiple nested loops.  This enables a variety of subsequent | 
|  | 228 | optimizations.</li> | 
|  | 229 |  | 
|  | 230 | <li>The -adce pass can now eliminate calls to functions that do not not write to | 
|  | 231 | memory.</li> | 
|  | 232 |  | 
|  | 233 | <li>The link-time optimizer now runs the -prune-eh pass (to remove unused | 
| Chris Lattner | ea309ff | 2004-05-04 17:04:09 +0000 | [diff] [blame] | 234 | exception handlers).</li> | 
| Chris Lattner | 54dcea8 | 2004-04-13 14:43:35 +0000 | [diff] [blame] | 235 |  | 
| Chris Lattner | 2ad4878 | 2004-05-02 04:19:15 +0000 | [diff] [blame] | 236 | <li>The -simplifycfg pass can now eliminate simple correlated branches (such as | 
|  | 237 | "<tt>if (A < B && A < B)</tt>", and can turn short-circuiting | 
|  | 238 | operators into the strict versions when useful (such as "<tt>if (A < B || A | 
|  | 239 | > C)</tt>" into "<tt>if (A < B | A > C)</tt>"</li> | 
|  | 240 |  | 
| Chris Lattner | ea309ff | 2004-05-04 17:04:09 +0000 | [diff] [blame] | 241 | <li>LLVM now has infrastructure for (simple and sparse conditional) constant | 
|  | 242 | propagation of function calls.  It currently supports a few math library | 
|  | 243 | functions like sqrt/sin/cos/etc.</li> | 
| Chris Lattner | 249b355 | 2004-06-03 22:35:13 +0000 | [diff] [blame] | 244 |  | 
|  | 245 | <li>The C backend now emits <a href="http://llvm.cs.uiuc.edu/PR334">Syntactic | 
|  | 246 | loops</a> in the code to help C compilers whose optimizers do not recognize | 
|  | 247 | loops formed from gotos (like GCC).</li> | 
| Brian Gaeke | 522235e | 2004-06-11 02:15:39 +0000 | [diff] [blame] | 248 |  | 
|  | 249 | <li>Fixed: <a href="http://llvm.cs.uiuc.edu/PR368">[sparcv9] null | 
|  | 250 | often spilled to constant pool</a>.</li> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 251 | </ol> | 
| Reid Spencer | 3e58f58 | 2004-05-23 17:23:13 +0000 | [diff] [blame] | 252 | </div> | 
| Chris Lattner | ba7bd47 | 2003-12-06 20:22:41 +0000 | [diff] [blame] | 253 |  | 
|  | 254 | <!--=========================================================================--> | 
|  | 255 | <div class="doc_subsubsection"> | 
| Misha Brukman | 017f2f3 | 2004-04-19 02:56:49 +0000 | [diff] [blame] | 256 | <a name="bugfix">In this release, the following bugs in the previous release | 
|  | 257 | were fixed:</a> | 
| Chris Lattner | ba7bd47 | 2003-12-06 20:22:41 +0000 | [diff] [blame] | 258 | </div> | 
|  | 259 |  | 
| Chris Lattner | 21a9040 | 2004-05-24 04:50:25 +0000 | [diff] [blame] | 260 | <div class="doc_text"> | 
|  | 261 |  | 
| Chris Lattner | ba7bd47 | 2003-12-06 20:22:41 +0000 | [diff] [blame] | 262 | <p>Bugs in the LLVM Core:</p> | 
| Chris Lattner | e7525b5 | 2003-10-07 21:38:31 +0000 | [diff] [blame] | 263 |  | 
|  | 264 | <ol> | 
| John Criswell | 6956afa | 2004-05-06 22:23:24 +0000 | [diff] [blame] | 265 | <li><a href="http://llvm.cs.uiuc.edu/PR330">[vmcore] Linker causes erroneous | 
|  | 266 | asssertion</a></li> | 
| Misha Brukman | 017f2f3 | 2004-04-19 02:56:49 +0000 | [diff] [blame] | 267 | <li><a href="http://llvm.cs.uiuc.edu/PR306">[loopsimplify] Loop simplify | 
|  | 268 | incorrectly updates dominator information</a></li> | 
|  | 269 | <li><a href="http://llvm.cs.uiuc.edu/PR310">[tailduplicate] DemoteRegToStack | 
|  | 270 | breaks SSA form</a></li> | 
|  | 271 | <li><a href="http://llvm.cs.uiuc.edu/PR313">[X86] JIT miscompiles unsigned short | 
|  | 272 | to floating point cast</a></li> | 
| Misha Brukman | fa50a22 | 2004-05-12 21:46:05 +0000 | [diff] [blame] | 273 | <li><a href="http://llvm.cs.uiuc.edu/PR332">[adce] Crash handling unreachable | 
|  | 274 | code that unwinds</a></li> | 
|  | 275 | <li><a href="http://llvm.cs.uiuc.edu/PR333">[sparc] LLC can't emit 2 functions | 
|  | 276 | of the same name, both having constant pools</a></li> | 
|  | 277 | <li><a href="http://llvm.cs.uiuc.edu/PR337">[livevar] Live variables missed | 
|  | 278 | physical register use of aliased definition</a></li> | 
| Chris Lattner | 8f7cf27 | 2004-05-21 16:48:20 +0000 | [diff] [blame] | 279 | <li><a href="http://llvm.cs.uiuc.edu/PR340">Verifier misses malformed switch instruction</a></li> | 
| Chris Lattner | 3edb94b | 2004-06-01 21:52:45 +0000 | [diff] [blame] | 280 | <li><a href="http://llvm.cs.uiuc.edu/PR315">[jit] abort, don't warn, when missing external functions encountered</a></li> | 
| Chris Lattner | 4e71aa8 | 2004-06-11 04:35:21 +0000 | [diff] [blame] | 281 | <li><a href="http://llvm.cs.uiuc.edu/PR369">[X86] stackifier crash on floating point setcc X, X</a></li> | 
| Chris Lattner | ba7bd47 | 2003-12-06 20:22:41 +0000 | [diff] [blame] | 282 | </ol> | 
|  | 283 |  | 
| Chris Lattner | ba7bd47 | 2003-12-06 20:22:41 +0000 | [diff] [blame] | 284 | <p>Bugs in the C/C++ front-end:</p> | 
|  | 285 |  | 
|  | 286 | <ol> | 
| Chris Lattner | b7a6a33 | 2004-06-20 19:08:50 +0000 | [diff] [blame] | 287 | <li><a href="http://llvm.cs.uiuc.edu/PR377">[llvmgcc] miscompilation of staticly initialized unsigned bitfields</a></li> | 
| Misha Brukman | fa50a22 | 2004-05-12 21:46:05 +0000 | [diff] [blame] | 288 | <li><a href="http://llvm.cs.uiuc.edu/PR326">[llvmgcc] Crash on use of undeclared | 
|  | 289 | enum type</a></li> | 
|  | 290 | <li><a href="http://llvm.cs.uiuc.edu/PR298">[llvmgcc] Variable length array | 
|  | 291 | indexing miscompiled</a></li> | 
| Chris Lattner | 2ef024b | 2004-06-19 01:11:02 +0000 | [diff] [blame] | 292 | <li><a href="http://llvm.cs.uiuc.edu/PR355">[llvmgcc] Errors handling function | 
|  | 293 | prototypes that take opaque structs by-value</a></li> | 
|  | 294 | <li><a href="http://llvm.cs.uiuc.edu/PR374">[llvmgcc] Crash compiling variable | 
|  | 295 | length array of structures</a></li> | 
| Chris Lattner | ba7bd47 | 2003-12-06 20:22:41 +0000 | [diff] [blame] | 296 | </ol> | 
| Chris Lattner | 21a9040 | 2004-05-24 04:50:25 +0000 | [diff] [blame] | 297 | </div> | 
| Reid Spencer | 3e58f58 | 2004-05-23 17:23:13 +0000 | [diff] [blame] | 298 |  | 
| Chris Lattner | 6249576 | 2003-10-02 16:38:05 +0000 | [diff] [blame] | 299 | <!-- *********************************************************************** --> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 300 | <div class="doc_section"> | 
|  | 301 | <a name="portability">Portability and Supported Platforms</a> | 
|  | 302 | </div> | 
| Chris Lattner | 6249576 | 2003-10-02 16:38:05 +0000 | [diff] [blame] | 303 | <!-- *********************************************************************** --> | 
|  | 304 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 305 | <div class="doc_text"> | 
|  | 306 |  | 
| Chris Lattner | 2c7b087 | 2004-06-01 18:22:41 +0000 | [diff] [blame] | 307 | <p>LLVM is known to work in the following platforms:</p> | 
|  | 308 |  | 
|  | 309 | <ul> | 
|  | 310 | <li>Intel and AMD machines running Red Hat Linux and FreeBSD (and probably | 
|  | 311 | other unix-like systems).</li> | 
|  | 312 | <li>Sun UltraSPARC workstations running Solaris 8.</li> | 
|  | 313 | <li>PowerPC-based Mac OS X boxes, running 10.3 and above (C backend and | 
|  | 314 | interpreter only, no native codegen is available yet).</li> | 
|  | 315 | <li>Intel and AMD machines running on Win32 with the Cygwin libraries.</li> | 
|  | 316 | </ul> | 
|  | 317 |  | 
| Brian Gaeke | e3e557e | 2004-05-09 05:28:35 +0000 | [diff] [blame] | 318 |  | 
|  | 319 | <p>The core LLVM infrastructure uses | 
|  | 320 | <a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself | 
|  | 321 | to the machine and operating system on which it is built.  However, minor | 
|  | 322 | porting may be required to get LLVM to work on new platforms.  We welcome your | 
|  | 323 | portability patches and reports of successful builds or error messages.</p> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 324 |  | 
| Chris Lattner | 2c7b087 | 2004-06-01 18:22:41 +0000 | [diff] [blame] | 325 | <p>Note that the LLVM build system does not currently support directories with | 
|  | 326 | spaces on them when running on Win32/cygwin.  We strongly recommend running | 
|  | 327 | LLVM and the C frontend out of a top-level directory without spaces (e.g., | 
| Chris Lattner | ce1a384 | 2004-06-01 19:41:30 +0000 | [diff] [blame] | 328 | <tt>/cygdrive/c/llvm</tt>).  Also, make sure to install <b>all</b> of the | 
|  | 329 | cygwin packages.  By default, many important tools are not installed that | 
|  | 330 | are needed by the LLVM build process or test suite (e.g., /bin/time).</p> | 
| Chris Lattner | 2c7b087 | 2004-06-01 18:22:41 +0000 | [diff] [blame] | 331 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 332 | </div> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 333 |  | 
| Brian Gaeke | 86a6c75 | 2004-04-20 18:18:46 +0000 | [diff] [blame] | 334 | <!--=========================================================================--> | 
|  | 335 | <div class="doc_subsection"> | 
|  | 336 | In this release, the following portability problems were fixed: | 
|  | 337 | </div> | 
|  | 338 |  | 
| Chris Lattner | 21a9040 | 2004-05-24 04:50:25 +0000 | [diff] [blame] | 339 | <div class="doc_text"> | 
|  | 340 |  | 
| Brian Gaeke | 86a6c75 | 2004-04-20 18:18:46 +0000 | [diff] [blame] | 341 | <ol> | 
| Misha Brukman | fa50a22 | 2004-05-12 21:46:05 +0000 | [diff] [blame] | 342 | <li><a href="http://llvm.cs.uiuc.edu/PR304">warnings compiling Stacker compiler | 
|  | 343 | on Mac OS X</a></li> | 
|  | 344 | <li><a href="http://llvm.cs.uiuc.edu/PR308">Archive file reader doesn't | 
|  | 345 | understand abbreviated names in headers</a></li> | 
| Brian Gaeke | 86a6c75 | 2004-04-20 18:18:46 +0000 | [diff] [blame] | 346 | </ol> | 
|  | 347 |  | 
| Chris Lattner | 21a9040 | 2004-05-24 04:50:25 +0000 | [diff] [blame] | 348 | </div> | 
|  | 349 |  | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 350 | <!-- *********************************************************************** --> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 351 | <div class="doc_section"> | 
|  | 352 | <a name="knownproblems">Known Problems</a> | 
|  | 353 | </div> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 354 | <!-- *********************************************************************** --> | 
|  | 355 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 356 | <div class="doc_text"> | 
|  | 357 |  | 
|  | 358 | <p>This section contains all known problems with the LLVM system, listed by | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 359 | component.  As new problems are discovered, they will be added to these | 
| Chris Lattner | b84f332 | 2003-12-12 21:22:16 +0000 | [diff] [blame] | 360 | sections.  If you run into a problem, please check the <a | 
| John Criswell | 86a3a48 | 2003-12-18 16:43:17 +0000 | [diff] [blame] | 361 | href="http://llvm.cs.uiuc.edu/bugs/">LLVM bug database</a> and submit a bug if | 
| Chris Lattner | b84f332 | 2003-12-12 21:22:16 +0000 | [diff] [blame] | 362 | there isn't already one.</p> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 363 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 364 | </div> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 365 |  | 
| Chris Lattner | b911de4 | 2004-03-14 02:03:02 +0000 | [diff] [blame] | 366 | <!-- ======================================================================= --> | 
|  | 367 | <div class="doc_subsection"> | 
|  | 368 | <a name="experimental">Experimental features included with this release</a> | 
|  | 369 | </div> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 370 |  | 
| Chris Lattner | b911de4 | 2004-03-14 02:03:02 +0000 | [diff] [blame] | 371 | <div class="doc_text"> | 
|  | 372 |  | 
| Misha Brukman | fa50a22 | 2004-05-12 21:46:05 +0000 | [diff] [blame] | 373 | <p>The following components of this LLVM release are either untested, known to | 
|  | 374 | be broken or unreliable, or are in early development.  These components should | 
|  | 375 | not be relied on, and bugs should not be filed against them, but they may be | 
|  | 376 | useful to some people.  In particular, if you would like to work on one of these | 
|  | 377 | components, please contact us on the llvmdev list.</p> | 
| Chris Lattner | b911de4 | 2004-03-14 02:03:02 +0000 | [diff] [blame] | 378 |  | 
|  | 379 | <ul> | 
|  | 380 | <li>The following passes are incomplete or buggy: <tt>-pgmdep, -memdep, | 
| Chris Lattner | 9958350 | 2004-06-28 00:44:45 +0000 | [diff] [blame^] | 381 | -ipmodref, -cee</tt></li> | 
| Chris Lattner | b911de4 | 2004-03-14 02:03:02 +0000 | [diff] [blame] | 382 |  | 
|  | 383 | <li>The <tt>-pre</tt> pass is incomplete (there are cases it doesn't handle that | 
|  | 384 | it should) and not thoroughly tested.</li> | 
|  | 385 | <li>The <tt>llvm-ar</tt> tool is incomplete and probably buggy.</li> | 
|  | 386 | <li>The <tt>llvm-db</tt> tool is in a very early stage of development.</li> | 
|  | 387 | </ul> | 
|  | 388 |  | 
|  | 389 | </div> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 390 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 391 | <!-- ======================================================================= --> | 
|  | 392 | <div class="doc_subsection"> | 
|  | 393 | <a name="core">Known problems with the LLVM Core</a> | 
|  | 394 | </div> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 395 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 396 | <div class="doc_text"> | 
|  | 397 |  | 
|  | 398 | <ul> | 
|  | 399 |  | 
|  | 400 | <li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not | 
|  | 401 | work.</li> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 402 |  | 
|  | 403 | <li>The JIT does not use mutexes to protect its internal data structures.  As | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 404 | such, execution of a threaded program could cause these data structures to be | 
|  | 405 | corrupted.</li> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 406 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 407 | <li>It is not possible to <tt>dlopen</tt> an LLVM bytecode file in the JIT.</li> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 408 |  | 
| Chris Lattner | a623e48 | 2003-10-20 19:05:03 +0000 | [diff] [blame] | 409 | <li>Linking in static archive files (.a files) is very slow (there is no symbol | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 410 | table in the archive).</li> | 
| Chris Lattner | c679fbb | 2003-11-04 20:06:53 +0000 | [diff] [blame] | 411 |  | 
| Misha Brukman | 017f2f3 | 2004-04-19 02:56:49 +0000 | [diff] [blame] | 412 | <li>The gccld program <a href="http://llvm.cs.uiuc.edu/PR139">does not link | 
|  | 413 | objects/archives in the order specified on the command line.</a></li> | 
| Chris Lattner | aebc66a | 2004-02-15 23:09:07 +0000 | [diff] [blame] | 414 |  | 
|  | 415 | <li><a href="http://llvm.cs.uiuc.edu/PR240">The lower-invoke pass does not mark | 
| John Criswell | 5d6345a | 2004-03-12 21:29:42 +0000 | [diff] [blame] | 416 | values live across a setjmp as volatile</a>.  This missing feature only affects | 
| Chris Lattner | aebc66a | 2004-02-15 23:09:07 +0000 | [diff] [blame] | 417 | targets whose setjmp/longjmp libraries do not save and restore the entire | 
|  | 418 | register file.</li> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 419 | </ul> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 420 | </div> | 
|  | 421 |  | 
|  | 422 | <!-- ======================================================================= --> | 
|  | 423 | <div class="doc_subsection"> | 
|  | 424 | <a name="c-fe">Known problems with the C front-end</a> | 
|  | 425 | </div> | 
| Chris Lattner | 178f3db | 2003-10-02 05:07:23 +0000 | [diff] [blame] | 426 |  | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 427 | <!-- _______________________________________________________________________ --> | 
| Chris Lattner | 5a8a728 | 2003-12-14 05:03:43 +0000 | [diff] [blame] | 428 | <div class="doc_subsubsection">Bugs</div> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 429 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 430 | <div class="doc_text"> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 431 | <ul> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 432 | <li>C99 Variable sized arrays do not release stack memory when they go out of | 
|  | 433 | scope.  Thus, the following program may run out of stack space: | 
|  | 434 | <pre> | 
|  | 435 | for (i = 0; i != 1000000; ++i) { | 
|  | 436 | int X[n]; | 
|  | 437 | foo(X); | 
|  | 438 | } | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 439 | </pre></li> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 440 |  | 
| Misha Brukman | fa50a22 | 2004-05-12 21:46:05 +0000 | [diff] [blame] | 441 | <li>Initialization of global union variables can only be done <a | 
|  | 442 | href="http://llvm.cs.uiuc.edu/bugs/show_bug.cgi?id=162">with the largest union | 
|  | 443 | member</a>.</li> | 
| Chris Lattner | 1ab58dd | 2004-03-16 21:39:04 +0000 | [diff] [blame] | 444 |  | 
| Misha Brukman | 017f2f3 | 2004-04-19 02:56:49 +0000 | [diff] [blame] | 445 | <li><a href="http://llvm.cs.uiuc.edu/PR244">[llvm-gcc] Error when an implicitly | 
|  | 446 | external function is re-declared as static</a></li> | 
| Chris Lattner | 1ab58dd | 2004-03-16 21:39:04 +0000 | [diff] [blame] | 447 |  | 
| John Criswell | 86a3a48 | 2003-12-18 16:43:17 +0000 | [diff] [blame] | 448 | </ul> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 449 | </div> | 
|  | 450 |  | 
|  | 451 | <!-- _______________________________________________________________________ --> | 
|  | 452 | <div class="doc_subsubsection"> | 
|  | 453 | Notes | 
|  | 454 | </div> | 
|  | 455 |  | 
|  | 456 | <div class="doc_text"> | 
|  | 457 |  | 
|  | 458 | <ul> | 
|  | 459 |  | 
|  | 460 | <li>Inline assembly is not yet supported.</li> | 
| Chris Lattner | d2a7427 | 2003-10-27 18:30:37 +0000 | [diff] [blame] | 461 |  | 
|  | 462 | <li>"long double" is transformed by the front-end into "double".  There is no | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 463 | support for floating point data types of any size other than 32 and 64 | 
|  | 464 | bits.</li> | 
|  | 465 |  | 
|  | 466 | <li>The following Unix system functionality has not been tested and may not | 
|  | 467 | work: | 
| Misha Brukman | 7cb4e38 | 2003-11-22 01:00:11 +0000 | [diff] [blame] | 468 | <ol> | 
|  | 469 | <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the | 
|  | 470 | appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions.  Note that | 
|  | 471 | <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly. | 
|  | 472 | <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt> | 
|  | 473 | - These functions have not been tested. | 
|  | 474 | </ol></li> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 475 |  | 
|  | 476 | <li>Although many GCC extensions are supported, some are not.  In particular, | 
|  | 477 | the following extensions are known to <b>not be</b> supported: | 
|  | 478 | <ol> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 479 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Local-Labels.html#Local%20Labels">Local Labels</a>: Labels local to a block.</li> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 480 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Nested-Functions.html#Nested%20Functions">Nested Functions</a>: As in Algol and Pascal, lexical scoping of functions.</li> | 
|  | 481 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li> | 
|  | 482 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Extended-Asm.html#Extended%20Asm">Extended Asm</a>: Assembler instructions with C expressions as operands.</li> | 
| John Criswell | 86a3a48 | 2003-12-18 16:43:17 +0000 | [diff] [blame] | 483 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constraints.html#Constraints">Constraints</a>: Constraints for asm operands.</li> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 484 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Asm-Labels.html#Asm%20Labels">Asm Labels</a>: Specifying the assembler name to use for a C symbol.</li> | 
|  | 485 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Explicit-Reg-Vars.html#Explicit%20Reg%20Vars">Explicit Reg Vars</a>: Defining variables residing in specified registers.</li> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 486 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Vector-Extensions.html#Vector%20Extensions">Vector Extensions</a>: Using vector instructions through built-in functions.</li> | 
|  | 487 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Target-Builtins.html#Target%20Builtins">Target Builtins</a>:   Built-in functions specific to particular targets.</li> | 
|  | 488 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables.</li> | 
|  | 489 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Pragmas.html#Pragmas">Pragmas</a>: Pragmas accepted by GCC.</li> | 
| Misha Brukman | 7cb4e38 | 2003-11-22 01:00:11 +0000 | [diff] [blame] | 490 | </ol> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 491 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 492 | <p>The following GCC extensions are <b>partially</b> supported.  An ignored | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 493 | attribute means that the LLVM compiler ignores the presence of the attribute, | 
|  | 494 | but the code should still work.  An unsupported attribute is one which is | 
| John Criswell | 86a3a48 | 2003-12-18 16:43:17 +0000 | [diff] [blame] | 495 | ignored by the LLVM compiler and will cause a different interpretation of | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 496 | the program.</p> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 497 |  | 
|  | 498 | <ol> | 
|  | 499 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>: | 
|  | 500 | Arrays whose length is computed at run time.<br> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 501 | Supported, but allocated stack space is not freed until the function returns (noted above).</li> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 502 |  | 
|  | 503 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html#Function%20Attributes">Function Attributes</a>: | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 504 |  | 
| John Criswell | 86a3a48 | 2003-12-18 16:43:17 +0000 | [diff] [blame] | 505 | Declaring that functions have no side effects or that they can never | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 506 | return.<br> | 
|  | 507 |  | 
|  | 508 | <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>, | 
|  | 509 | <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>, | 
|  | 510 | <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br> | 
|  | 511 |  | 
|  | 512 | <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>, | 
|  | 513 | <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>, | 
|  | 514 | <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br> | 
|  | 515 |  | 
|  | 516 | <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>, | 
|  | 517 | <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>, | 
|  | 518 | <tt>fastcall</tt>, all other target specific attributes</li> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 519 |  | 
|  | 520 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>: | 
|  | 521 | Specifying attributes of variables.<br> | 
|  | 522 | <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>, | 
|  | 523 | <tt>deprecated</tt>, <tt>transparent_union</tt>, | 
|  | 524 | <tt>unused</tt>, <tt>weak</tt><br> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 525 |  | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 526 | <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>, | 
|  | 527 | <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>, | 
|  | 528 | <tt>vector_size</tt>, <tt>dllimport</tt>, | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 529 | <tt>dllexport</tt>, all target specific attributes.</li> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 530 |  | 
| Misha Brukman | 8395d73 | 2003-12-12 04:37:31 +0000 | [diff] [blame] | 531 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Type-Attributes.html#Type%20Attributes">Type Attributes</a>:	Specifying attributes of types.<br> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 532 | <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>, | 
| Misha Brukman | 8395d73 | 2003-12-12 04:37:31 +0000 | [diff] [blame] | 533 | <tt>deprecated</tt>, <tt>may_alias</tt><br> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 534 |  | 
|  | 535 | <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>, | 
|  | 536 | all target specific attributes.</li> | 
|  | 537 |  | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 538 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>: | 
|  | 539 | Other built-in functions.<br> | 
|  | 540 | We support all builtins which have a C language equivalent (e.g., | 
|  | 541 | <tt>__builtin_cos</tt>),  <tt>__builtin_alloca</tt>, | 
|  | 542 | <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>, | 
| Chris Lattner | b7c4bac | 2004-06-18 06:26:29 +0000 | [diff] [blame] | 543 | <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt> | 
|  | 544 | (currently ignored).  We also support builtins for ISO C99 floating | 
|  | 545 | point comparison macros (e.g., <tt>__builtin_islessequal</tt>).</li> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 546 | </ol> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 547 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 548 | <p>The following extensions <b>are</b> known to be supported:</p> | 
|  | 549 |  | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 550 | <ol> | 
| Chris Lattner | d3dc850 | 2004-03-16 08:54:07 +0000 | [diff] [blame] | 551 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Labels-as-Values.html#Labels%20as%20Values">Labels as Values</a>: Getting pointers to labels and computed gotos.</li> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 552 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>:   Putting statements and declarations inside expressions.</li> | 
|  | 553 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Typeof.html#Typeof">Typeof</a>: <code>typeof</code>: referring to the type of an expression.</li> | 
| Tanya Lattner | ce33a1b | 2004-06-22 03:48:17 +0000 | [diff] [blame] | 554 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc-3.4.0/gcc/Lvalues.html#Lvalues">Lvalues</a>: Using <code>?:</code>, "<code>,</code>" and casts in lvalues.</li> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 555 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li> | 
|  | 556 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li> | 
|  | 557 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>:   Data types for complex numbers.</li> | 
|  | 558 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li> | 
|  | 559 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li> | 
|  | 560 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li> | 
|  | 561 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variadic-Macros.html#Variadic%20Macros">Variadic Macros</a>: Macros with a variable number of arguments.</li> | 
|  | 562 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>:  Slightly looser rules for escaped newlines.</li> | 
|  | 563 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Subscripting.html#Subscripting">Subscripting</a>: Any array can be subscripted, even if not an lvalue.</li> | 
| Misha Brukman | 8395d73 | 2003-12-12 04:37:31 +0000 | [diff] [blame] | 564 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Pointer-Arith.html#Pointer%20Arith">Pointer Arith</a>: Arithmetic on <code>void</code>-pointers and function pointers.</li> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 565 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Initializers.html#Initializers">Initializers</a>: Non-constant initializers.</li> | 
| John Criswell | 86a3a48 | 2003-12-18 16:43:17 +0000 | [diff] [blame] | 566 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions, | 
|  | 567 | or arrays as values.</li> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 568 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Designated-Inits.html#Designated%20Inits">Designated Inits</a>: Labeling elements of initializers.</li> | 
| Misha Brukman | 8395d73 | 2003-12-12 04:37:31 +0000 | [diff] [blame] | 569 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Cast-to-Union.html#Cast%20to%20Union">Cast to Union</a>: Casting to union type from any member of the union.</li> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 570 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li> | 
|  | 571 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li> | 
|  | 572 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li> | 
|  | 573 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C---Comments.html#C++%20Comments">C++ Comments</a>: C++ comments are recognized.</li> | 
|  | 574 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li> | 
|  | 575 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Character-Escapes.html#Character%20Escapes">Character Escapes</a>: <code>\e</code> stands for the character <ESC>.</li> | 
|  | 576 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li> | 
|  | 577 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li> | 
|  | 578 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alternate-Keywords.html#Alternate%20Keywords">Alternate Keywords</a>:<code>__const__</code>, <code>__asm__</code>, etc., for header files.</li> | 
|  | 579 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Incomplete-Enums.html#Incomplete%20Enums">Incomplete Enums</a>:  <code>enum foo;</code>, with details to follow.</li> | 
|  | 580 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Names.html#Function%20Names">Function Names</a>: Printable strings which are the name of the current function.</li> | 
| Chris Lattner | 3646dad | 2004-02-14 04:08:29 +0000 | [diff] [blame] | 581 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Return-Address.html#Return%20Address">Return Address</a>: Getting the return or frame address of a function.</li> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 582 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Unnamed-Fields.html#Unnamed%20Fields">Unnamed Fields</a>: Unnamed struct/union fields within structs/unions.</li> | 
|  | 583 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Attribute-Syntax.html#Attribute%20Syntax">Attribute Syntax</a>: Formal syntax for attributes.</li> | 
| Misha Brukman | 7cb4e38 | 2003-11-22 01:00:11 +0000 | [diff] [blame] | 584 | </ol></li> | 
|  | 585 |  | 
|  | 586 | </ul> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 587 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 588 | <p>If you run into GCC extensions which have not been included in any of these | 
|  | 589 | lists, please let us know (also including whether or not they work).</p> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 590 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 591 | </div> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 592 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 593 | <!-- ======================================================================= --> | 
|  | 594 | <div class="doc_subsection"> | 
|  | 595 | <a name="c++-fe">Known problems with the C++ front-end</a> | 
|  | 596 | </div> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 597 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 598 | <div class="doc_text"> | 
|  | 599 |  | 
| John Criswell | 86a3a48 | 2003-12-18 16:43:17 +0000 | [diff] [blame] | 600 | <p>For this release, the C++ front-end is considered to be fully functional but | 
| Chris Lattner | e76e9ab | 2003-12-12 04:25:33 +0000 | [diff] [blame] | 601 | has not been tested as thoroughly as the C front-end.  It has been tested and | 
|  | 602 | works for a number of non-trivial programs, but there may be lurking bugs. | 
|  | 603 | Please report any bugs or problems.</p> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 604 |  | 
|  | 605 | </div> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 606 |  | 
|  | 607 | <!-- _______________________________________________________________________ --> | 
| Chris Lattner | 141ebb6 | 2004-02-14 04:12:41 +0000 | [diff] [blame] | 608 | <div class="doc_subsubsection">Bugs</div> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 609 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 610 | <div class="doc_text"> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 611 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 612 | <ul> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 613 | <li>The C++ front-end inherits all problems afflicting the <a href="#c-fe">C | 
| John Criswell | 86a3a48 | 2003-12-18 16:43:17 +0000 | [diff] [blame] | 614 | front-end</a>.</li> | 
| John Criswell | 86a3a48 | 2003-12-18 16:43:17 +0000 | [diff] [blame] | 615 | </ul> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 616 | </div> | 
|  | 617 |  | 
|  | 618 | <!-- _______________________________________________________________________ --> | 
|  | 619 | <div class="doc_subsubsection"> | 
|  | 620 | Notes | 
|  | 621 | </div> | 
|  | 622 |  | 
|  | 623 | <div class="doc_text"> | 
|  | 624 |  | 
|  | 625 | <ul> | 
| Chris Lattner | d2a7427 | 2003-10-27 18:30:37 +0000 | [diff] [blame] | 626 |  | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 627 | <li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser.  This | 
|  | 628 | parser is significantly more standards compliant (and picky) than prior GCC | 
|  | 629 | versions.  For more information, see the C++ section of the <a | 
| Chris Lattner | e76e9ab | 2003-12-12 04:25:33 +0000 | [diff] [blame] | 630 | href="http://gcc.gnu.org/gcc-3.4/changes.html">GCC 3.4 release notes</a>.</li> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 631 |  | 
|  | 632 | <li>Destructors for local objects are not always run when a <tt>longjmp</tt> is | 
| Chris Lattner | 6249576 | 2003-10-02 16:38:05 +0000 | [diff] [blame] | 633 | performed. In particular, destructors for objects in the <tt>longjmp</tt>ing | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 634 | function and in the <tt>setjmp</tt> receiver function may not be run. | 
| John Criswell | 86a3a48 | 2003-12-18 16:43:17 +0000 | [diff] [blame] | 635 | Objects in intervening stack frames will be destroyed, however (which is | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 636 | better than most compilers).</li> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 637 |  | 
| Chris Lattner | 6249576 | 2003-10-02 16:38:05 +0000 | [diff] [blame] | 638 | <li>The LLVM C++ front-end follows the <a | 
|  | 639 | href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>. | 
|  | 640 | This document, which is not Itanium specific, specifies a standard for name | 
|  | 641 | mangling, class layout, v-table layout, RTTI formats, and other C++ | 
|  | 642 | representation issues.  Because we use this API, code generated by the LLVM | 
|  | 643 | compilers should be binary compatible with machine code generated by other | 
|  | 644 | Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc). | 
|  | 645 | <i>However</i>, the exception handling mechanism used by LLVM is very | 
|  | 646 | different from the model used in the Itanium ABI, so <b>exceptions will not | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 647 | interact correctly</b>. </li> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 648 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 649 | </ul> | 
| Chris Lattner | 46ecf61 | 2003-10-07 22:14:37 +0000 | [diff] [blame] | 650 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 651 | </div> | 
|  | 652 |  | 
|  | 653 | <!-- ======================================================================= --> | 
|  | 654 | <div class="doc_subsection"> | 
|  | 655 | <a name="x86-be">Known problems with the X86 back-end</a> | 
|  | 656 | </div> | 
|  | 657 |  | 
|  | 658 | <div class="doc_text"> | 
|  | 659 |  | 
|  | 660 | <ul> | 
| Reid Spencer | 006b386 | 2004-06-19 18:24:05 +0000 | [diff] [blame] | 661 | <li>Optimized (Release) versions of LLVM built with GCC 3.3.2 or 3.3.3 will | 
|  | 662 | produce an llc tool that always enters an infinite loop due to what | 
|  | 663 | appears to be an optimization bug (-O2 and -O3) in those versions of GCC. | 
|  | 664 | This problem does not happen in GCC 3.3.1 nor GCC 3.4.0 nor does it happen if | 
|  | 665 | you build a Debug version of LLVM. You are cautioned not to use GCC 3.3.2 or | 
|  | 666 | GCC 3.3.3 to build Optimized versions of LLVM. It is unclear whether this problem | 
|  | 667 | affects other backends but it is unlikely.</li> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 668 | </ul> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 669 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 670 | </div> | 
|  | 671 |  | 
|  | 672 | <!-- ======================================================================= --> | 
|  | 673 | <div class="doc_subsection"> | 
|  | 674 | <a name="sparc-be">Known problems with the Sparc back-end</a> | 
|  | 675 | </div> | 
|  | 676 |  | 
|  | 677 | <div class="doc_text"> | 
|  | 678 |  | 
|  | 679 | <ul> | 
| Chris Lattner | 9e0b81c | 2004-03-19 19:22:28 +0000 | [diff] [blame] | 680 | <li>There are several programs in the LLVM testsuite that the Sparc code generator is known to miscompile.</li> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 681 | </ul> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 682 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 683 | </div> | 
|  | 684 |  | 
|  | 685 | <!-- ======================================================================= --> | 
|  | 686 | <div class="doc_subsection"> | 
|  | 687 | <a name="c-be">Known problems with the C back-end</a> | 
|  | 688 | </div> | 
|  | 689 |  | 
|  | 690 | <div class="doc_text"> | 
|  | 691 |  | 
|  | 692 | <ul> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 693 |  | 
|  | 694 | <li>The C back-end produces code that violates the ANSI C Type-Based Alias | 
|  | 695 | Analysis rules.  As such, special options may be necessary to compile the code | 
|  | 696 | (for example, GCC requires the <tt>-fno-strict-aliasing</tt> option).  This | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 697 | problem probably cannot be fixed.</li> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 698 |  | 
| Chris Lattner | a623e48 | 2003-10-20 19:05:03 +0000 | [diff] [blame] | 699 | <li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 700 | cannot include special floating point numbers like Not-A-Number or | 
|  | 701 | Infinity.</li> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 702 |  | 
| Chris Lattner | c679fbb | 2003-11-04 20:06:53 +0000 | [diff] [blame] | 703 | <li><a href="http://llvm.cs.uiuc.edu/PR56">Zero arg vararg functions are not | 
| Chris Lattner | b28c328 | 2003-10-24 04:03:19 +0000 | [diff] [blame] | 704 | supported</a>.  This should not affect LLVM produced by the C or C++ | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 705 | frontends.</li> | 
| Chris Lattner | b28c328 | 2003-10-24 04:03:19 +0000 | [diff] [blame] | 706 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 707 | </ul> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 708 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 709 | </div> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 710 |  | 
|  | 711 | <!-- *********************************************************************** --> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 712 | <div class="doc_section"> | 
|  | 713 | <a name="additionalinfo">Additional Information</a> | 
|  | 714 | </div> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 715 | <!-- *********************************************************************** --> | 
|  | 716 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 717 | <div class="doc_text"> | 
|  | 718 |  | 
|  | 719 | <p>A wide variety of additional information is available on the LLVM web page, | 
| John Criswell | 86a3a48 | 2003-12-18 16:43:17 +0000 | [diff] [blame] | 720 | including mailing lists and publications describing algorithms and components | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 721 | implemented in LLVM.  The web page also contains versions of the API | 
|  | 722 | documentation which is up-to-date with the CVS version of the source code.  You | 
|  | 723 | can access versions of these documents specific to this release by going into | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 724 | the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 725 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 726 | <p>If you have any questions or comments about LLVM, please feel free to contact | 
| Chris Lattner | b84f332 | 2003-12-12 21:22:16 +0000 | [diff] [blame] | 727 | us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing | 
|  | 728 | lists</a>.</p> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 729 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 730 | </div> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 731 |  | 
|  | 732 | <!-- *********************************************************************** --> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 733 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 734 | <hr> | 
| Misha Brukman | 68aab3b | 2003-11-22 01:23:39 +0000 | [diff] [blame] | 735 | <address> | 
| Misha Brukman | 8834af9 | 2003-12-21 22:53:21 +0000 | [diff] [blame] | 736 | <a href="http://jigsaw.w3.org/css-validator/check/referer"><img | 
| Misha Brukman | 68aab3b | 2003-11-22 01:23:39 +0000 | [diff] [blame] | 737 | src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a> | 
|  | 738 | <a href="http://validator.w3.org/check/referer"><img | 
|  | 739 | src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a> | 
|  | 740 |  | 
| Misha Brukman | 7cb4e38 | 2003-11-22 01:00:11 +0000 | [diff] [blame] | 741 | <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br> | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 742 | Last modified: $Date$ | 
| Misha Brukman | 68aab3b | 2003-11-22 01:23:39 +0000 | [diff] [blame] | 743 | </address> | 
| Chris Lattner | 3d48250 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 744 |  | 
| Misha Brukman | 80731b9 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 745 | </body> | 
|  | 746 | </html> |