Misha Brukman | 500bc30 | 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> |
Reid Spencer | 6454ed3 | 2004-11-18 18:38:58 +0000 | [diff] [blame] | 5 | <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 6 | <link rel="stylesheet" href="llvm.css" type="text/css"> |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 7 | <title>LLVM 2.1 Release Notes</title> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 8 | </head> |
| 9 | <body> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 10 | |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 11 | <div class="doc_title">LLVM 2.1 Release Notes</div> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 12 | |
| 13 | <ol> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 14 | <li><a href="#intro">Introduction</a></li> |
| 15 | <li><a href="#whatsnew">What's New?</a></li> |
Chris Lattner | 4b538b9 | 2004-04-30 22:17:12 +0000 | [diff] [blame] | 16 | <li><a href="GettingStarted.html">Installation Instructions</a></li> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 17 | <li><a href="#portability">Portability and Supported Platforms</a></li> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 18 | <li><a href="#knownproblems">Known Problems</a> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 19 | <li><a href="#additionalinfo">Additional Information</a></li> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 20 | </ol> |
| 21 | |
Chris Lattner | 7911ce2 | 2004-05-23 21:07:27 +0000 | [diff] [blame] | 22 | <div class="doc_author"> |
Chris Lattner | c463b27 | 2005-10-29 07:07:09 +0000 | [diff] [blame] | 23 | <p>Written by the <a href="http://llvm.org">LLVM Team</a><p> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 24 | </div> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 25 | |
| 26 | <!-- *********************************************************************** --> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 27 | <div class="doc_section"> |
| 28 | <a name="intro">Introduction</a> |
| 29 | </div> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 30 | <!-- *********************************************************************** --> |
| 31 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 32 | <div class="doc_text"> |
| 33 | |
| 34 | <p>This document contains the release notes for the LLVM compiler |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 35 | infrastructure, release 2.1. Here we describe the status of LLVM, including |
Chris Lattner | 57a460e | 2007-05-23 04:39:32 +0000 | [diff] [blame] | 36 | major improvements from the previous release and any known problems. All LLVM |
Chris Lattner | caf0634 | 2007-05-09 04:58:11 +0000 | [diff] [blame] | 37 | releases may be downloaded from the <a href="http://llvm.org/releases/">LLVM |
Chris Lattner | 57a460e | 2007-05-23 04:39:32 +0000 | [diff] [blame] | 38 | releases web site</a>.</p> |
Chris Lattner | 1909261 | 2003-10-02 16:38:05 +0000 | [diff] [blame] | 39 | |
Chris Lattner | 7506b1d | 2004-12-07 08:04:13 +0000 | [diff] [blame] | 40 | <p>For more information about LLVM, including information about the latest |
Chris Lattner | c463b27 | 2005-10-29 07:07:09 +0000 | [diff] [blame] | 41 | release, please check out the <a href="http://llvm.org/">main LLVM |
Chris Lattner | 47ad72c | 2003-10-07 21:38:31 +0000 | [diff] [blame] | 42 | web site</a>. If you have questions or comments, the <a |
| 43 | href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM developer's mailing |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 44 | list</a> is a good place to send them.</p> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 45 | |
Reid Spencer | 669ed45 | 2007-07-09 08:04:31 +0000 | [diff] [blame] | 46 | <p>Note that if you are reading this file from a Subversion checkout or the |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 47 | main LLVM web page, this document applies to the <i>next</i> release, not the |
| 48 | current one. To see the release notes for a specific releases, please see the |
| 49 | <a href="http://llvm.org/releases/">releases page</a>.</p> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 50 | |
| 51 | </div> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 52 | |
| 53 | <!-- *********************************************************************** --> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 54 | <div class="doc_section"> |
| 55 | <a name="whatsnew">What's New?</a> |
| 56 | </div> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 57 | <!-- *********************************************************************** --> |
| 58 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 59 | <div class="doc_text"> |
| 60 | |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 61 | <p>This is the twelfth public release of the LLVM Compiler Infrastructure. |
| 62 | It includes many features and refinements from LLVM 2.0.</p> |
Chris Lattner | a509996 | 2003-12-06 20:22:41 +0000 | [diff] [blame] | 63 | |
Chris Lattner | 80453c9 | 2004-05-24 04:50:25 +0000 | [diff] [blame] | 64 | </div> |
| 65 | |
Chris Lattner | a509996 | 2003-12-06 20:22:41 +0000 | [diff] [blame] | 66 | <!--=========================================================================--> |
Chris Lattner | 8a45876 | 2005-05-15 05:44:51 +0000 | [diff] [blame] | 67 | <div class="doc_subsection"> |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 68 | <a name="frontends">New Frontends</a> |
Chris Lattner | 44c933e | 2006-04-18 06:18:36 +0000 | [diff] [blame] | 69 | </div> |
| 70 | |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 71 | <div class="doc_text"> |
Chris Lattner | 60893e5 | 2007-05-18 06:33:02 +0000 | [diff] [blame] | 72 | |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 73 | <p>LLVM 2.1 brings two new beta C front-ends. First, Duncan, Anton and Devang |
| 74 | start syncing up llvm-gcc with GCC 4.2, yielding "llvm-gcc 4.2" (creative, |
| 75 | huh?). llvm-gcc 4.2 has the promise to bring much better FORTRAN and Ada |
| 76 | support to LLVM as well as features like atomic builtins, OpenMP, and many other |
| 77 | things. Check it out!</p> |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 78 | |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 79 | <p>Second, LLVM now includes its own native C and Objective-C front-end (C++ is |
| 80 | in progress, but is not very far along) code named "<a |
| 81 | href="http://clang.llvm.org/">clang</a>". This front-end has a number of great |
| 82 | features, primarily aimed at source-level analysis and speeding up compile-time. |
| 83 | At this point though, the LLVM Code Generator component is still very early in |
| 84 | development, so it's mostly useful for people looking to build source-level |
| 85 | analysis tools or source-to-source translators.</p> |
Chris Lattner | 60893e5 | 2007-05-18 06:33:02 +0000 | [diff] [blame] | 86 | |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 87 | </div> |
| 88 | |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 89 | <!--=========================================================================--> |
| 90 | <div class="doc_subsection"> |
| 91 | <a name="optimizer">Optimizer Improvements</a> |
| 92 | </div> |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 93 | |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 94 | <div class="doc_text"> |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 95 | |
| 96 | <p>Some of the most noticable improvements this release have been in the |
| 97 | optimizer, speeding it up and making it more aggressive</p> |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 98 | |
| 99 | <ul> |
Tanya Lattner | b6ec3a9 | 2007-05-16 23:25:46 +0000 | [diff] [blame] | 100 | |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 101 | <li>Owen DSE and MemDep analysis</li> |
| 102 | <li>Owen GVN</li> |
| 103 | <li>Owen GVN-PRE, not in llvm-gcc</li> |
| 104 | <li>Devang merged ETForest and DomTree into a single easier to use data |
| 105 | structure.</li> |
| 106 | <li>Nick Lewycky improved loop trip count analysis to handle many more common |
| 107 | cases.</li> |
Tanya Lattner | b6ec3a9 | 2007-05-16 23:25:46 +0000 | [diff] [blame] | 108 | |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 109 | </ul> |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 110 | |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 111 | </div> |
| 112 | |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 113 | <!--=========================================================================--> |
| 114 | <div class="doc_subsection"> |
| 115 | <a name="codegen">Code Generator Improvements</a> |
| 116 | </div> |
| 117 | |
| 118 | <div class="doc_text"> |
| 119 | |
| 120 | <p>foo</p> |
| 121 | |
| 122 | <ul> |
| 123 | |
| 124 | <li>Dale finished up the Tail Merging optimization in the code generator, |
| 125 | enabling it by default. This produces smaller code that is also faster in some |
| 126 | cases.</li> |
| 127 | |
| 128 | <li>Dan Gohman changed the way we represent vectors before legalization, |
| 129 | significantly simplifying the SelectionDAG representation for these and making |
| 130 | the code generator faster for vector code.</li> |
| 131 | |
| 132 | <li>Evan remat rewrite (coallesced intervals + folding of remat'd loads) and |
| 133 | live intervals improvements.</li> |
| 134 | |
| 135 | <li>Dan Gohman contributed support for better alignment and volatility handling |
| 136 | in the code generator, and significantly enhanced alignment analysis for SSE |
| 137 | load/store instructions.</li> |
| 138 | |
| 139 | <li>Christopher Lamb virtual register sub-register support, better truncates and |
| 140 | extends on X86.</li> |
| 141 | |
| 142 | <li>Duraid Madina contributed a new "bigblock" register allocator, and Roman |
| 143 | Levenstein contributed several big improvements. BigBlock is optimized for code |
| 144 | that uses very large basic blocks. It is slightly slower than the "local" |
| 145 | allocator, but produces much better code.</li> |
| 146 | |
| 147 | <li>David Greene refactored the register allocator to split coallescing out from |
| 148 | allocation, making coallescers pluggable.</li> |
| 149 | |
| 150 | </ul> |
| 151 | |
| 152 | </div> |
| 153 | |
| 154 | |
| 155 | <!--=========================================================================--> |
| 156 | <div class="doc_subsection"> |
| 157 | <a name="targetspecific">Target Specific Improvements</a> |
| 158 | </div> |
Chris Lattner | 60893e5 | 2007-05-18 06:33:02 +0000 | [diff] [blame] | 159 | |
Chris Lattner | 738bd30 | 2006-04-18 06:32:08 +0000 | [diff] [blame] | 160 | <div class="doc_text"> |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 161 | <p>New features include: |
| 162 | </p> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 163 | |
| 164 | <ul> |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 165 | <li>Bruno Cardoso Lopes contributed initial MIPS support.</li> |
| 166 | <li>Bill Wendling added SSSE3 support.</li> |
| 167 | <li>New Target independent if converter, ARM uses it so far</li> |
| 168 | <li>Nicholas Geoffray contributed improved linux/ppc ABI and JIT support.</li> |
| 169 | <li>Dale Johannesen rewrote handling of 32-bit float values in the X86 backend |
| 170 | when using the floating point stack, fixing several nasty bugs.</li> |
| 171 | <li>Dan contributed rematerialization support for the X86 backend.</li> |
| 172 | </ul> |
| 173 | |
| 174 | </div> |
Chris Lattner | 57a460e | 2007-05-23 04:39:32 +0000 | [diff] [blame] | 175 | |
Chris Lattner | 57a460e | 2007-05-23 04:39:32 +0000 | [diff] [blame] | 176 | |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 177 | <!--=========================================================================--> |
| 178 | <div class="doc_subsection"> |
| 179 | <a name="llvmgccimprovements">llvm-gcc Improvements</a> |
| 180 | </div> |
Tanya Lattner | b6ec3a9 | 2007-05-16 23:25:46 +0000 | [diff] [blame] | 181 | |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 182 | <div class="doc_text"> |
| 183 | <p>New features include: |
| 184 | </p> |
Tanya Lattner | b6ec3a9 | 2007-05-16 23:25:46 +0000 | [diff] [blame] | 185 | |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 186 | <ul> |
| 187 | <li>Duncan and Anton exception handling in llvm-gcc 4.0/4.2</li> |
Tanya Lattner | b6ec3a9 | 2007-05-16 23:25:46 +0000 | [diff] [blame] | 188 | |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 189 | <li>Devang and Duncan: Bitfields, pragma pack</li> |
Chris Lattner | 60893e5 | 2007-05-18 06:33:02 +0000 | [diff] [blame] | 190 | |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 191 | <li>Tanya implemented support for __attribute__((noinline)) in llvm-gcc, and |
| 192 | added support for generic variable annotations which are propagated into the |
| 193 | LLVM IR, e.g. "<tt>int X __attribute__((annotate("myproperty")));</tt>".</li> |
| 194 | |
| 195 | <li>Sheng Zhou and Christopher Lamb implemented alias analysis support for |
| 196 | 'restrict' arguments to functions.</li> |
| 197 | |
| 198 | <li>Duncan contributed support for trampolines (pointers to nested functions), |
| 199 | currently only supported on x86 target.</li> |
Tanya Lattner | b6ec3a9 | 2007-05-16 23:25:46 +0000 | [diff] [blame] | 200 | |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 201 | </ul> |
| 202 | |
Chris Lattner | 738bd30 | 2006-04-18 06:32:08 +0000 | [diff] [blame] | 203 | </div> |
| 204 | |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 205 | |
| 206 | <!--=========================================================================--> |
| 207 | <div class="doc_subsection"> |
| 208 | <a name="coreimprovements">LLVM Core Improvements</a> |
| 209 | </div> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 210 | |
Chris Lattner | 1c1a85c | 2006-04-19 04:02:47 +0000 | [diff] [blame] | 211 | <div class="doc_text"> |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 212 | <p>New features include: |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 213 | </p> |
| 214 | |
| 215 | <ul> |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 216 | <li>Neil Booth APFloat, foundation for long double support that will be wrapped |
| 217 | up in 2.2. Dale contributed most of long double support, will be enabled in |
| 218 | 2.2.</li> |
Tanya Lattner | b6ec3a9 | 2007-05-16 23:25:46 +0000 | [diff] [blame] | 219 | |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 220 | <li>LLVM now provides an LLVMBuilder class which makes it significantly easier |
| 221 | to create LLVM IR instructions.</li> |
Tanya Lattner | b6ec3a9 | 2007-05-16 23:25:46 +0000 | [diff] [blame] | 222 | |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 223 | <li>Reid contributed support for intrinsics that take arbitrary integer typed |
| 224 | arguments, Dan Gohman and Chandler extended it to support FP and vectors.</li> |
Chris Lattner | bfb17ab | 2007-05-17 21:41:31 +0000 | [diff] [blame] | 225 | </li> |
| 226 | |
Chris Lattner | bfb17ab | 2007-05-17 21:41:31 +0000 | [diff] [blame] | 227 | </ul> |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 228 | |
Chris Lattner | bfb17ab | 2007-05-17 21:41:31 +0000 | [diff] [blame] | 229 | </div> |
Chris Lattner | c5d658a | 2006-03-03 00:34:26 +0000 | [diff] [blame] | 230 | |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame^] | 231 | <!--=========================================================================--> |
| 232 | <div class="doc_subsection"> |
| 233 | <a name="otherimprovements">Other Improvements</a> |
| 234 | </div> |
| 235 | |
| 236 | <div class="doc_text"> |
| 237 | <p>New features include: |
| 238 | </p> |
| 239 | |
| 240 | <ul> |
| 241 | <li>BrainF frontend by Sterling Stein.</li> |
| 242 | |
| 243 | <li>David Green contributed a new --enable-expensive-checks configure option |
| 244 | which enables STL checking, and fixed several bugs exposed by it.</li> |
| 245 | |
| 246 | </li> |
| 247 | |
| 248 | </ul> |
| 249 | |
| 250 | </div> |
Chris Lattner | c5d658a | 2006-03-03 00:34:26 +0000 | [diff] [blame] | 251 | |
Chris Lattner | 1909261 | 2003-10-02 16:38:05 +0000 | [diff] [blame] | 252 | <!-- *********************************************************************** --> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 253 | <div class="doc_section"> |
| 254 | <a name="portability">Portability and Supported Platforms</a> |
| 255 | </div> |
Chris Lattner | 1909261 | 2003-10-02 16:38:05 +0000 | [diff] [blame] | 256 | <!-- *********************************************************************** --> |
| 257 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 258 | <div class="doc_text"> |
| 259 | |
John Criswell | 0b5b5e9 | 2004-12-08 20:35:47 +0000 | [diff] [blame] | 260 | <p>LLVM is known to work on the following platforms:</p> |
Chris Lattner | 4654bdb | 2004-06-01 18:22:41 +0000 | [diff] [blame] | 261 | |
| 262 | <ul> |
Chris Lattner | 57a460e | 2007-05-23 04:39:32 +0000 | [diff] [blame] | 263 | <li>Intel and AMD machines running Red Hat Linux, Fedora Core and FreeBSD |
Reid Spencer | 00812e2 | 2005-05-17 02:47:27 +0000 | [diff] [blame] | 264 | (and probably other unix-like systems).</li> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 265 | <li>PowerPC and X86-based Mac OS X systems, running 10.2 and above in 32-bit and |
| 266 | 64-bit modes.</li> |
Chris Lattner | 57a460e | 2007-05-23 04:39:32 +0000 | [diff] [blame] | 267 | <li>Intel and AMD machines running on Win32 using MinGW libraries (native)</li> |
| 268 | <li>Intel and AMD machines running on Win32 with the Cygwin libraries (limited |
| 269 | support is available for native builds with Visual C++).</li> |
| 270 | <li>Sun UltraSPARC workstations running Solaris 8.</li> |
John Criswell | 9321fa8 | 2005-05-13 20:28:15 +0000 | [diff] [blame] | 271 | <li>Alpha-based machines running Debian GNU/Linux.</li> |
| 272 | <li>Itanium-based machines running Linux and HP-UX.</li> |
Chris Lattner | 4654bdb | 2004-06-01 18:22:41 +0000 | [diff] [blame] | 273 | </ul> |
| 274 | |
Brian Gaeke | b0fd761 | 2004-05-09 05:28:35 +0000 | [diff] [blame] | 275 | <p>The core LLVM infrastructure uses |
| 276 | <a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself |
| 277 | to the machine and operating system on which it is built. However, minor |
| 278 | porting may be required to get LLVM to work on new platforms. We welcome your |
| 279 | portability patches and reports of successful builds or error messages.</p> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 280 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 281 | </div> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 282 | |
| 283 | <!-- *********************************************************************** --> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 284 | <div class="doc_section"> |
| 285 | <a name="knownproblems">Known Problems</a> |
| 286 | </div> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 287 | <!-- *********************************************************************** --> |
| 288 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 289 | <div class="doc_text"> |
| 290 | |
| 291 | <p>This section contains all known problems with the LLVM system, listed by |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 292 | component. As new problems are discovered, they will be added to these |
Chris Lattner | 5eccca4 | 2003-12-12 21:22:16 +0000 | [diff] [blame] | 293 | sections. If you run into a problem, please check the <a |
Chris Lattner | c463b27 | 2005-10-29 07:07:09 +0000 | [diff] [blame] | 294 | href="http://llvm.org/bugs/">LLVM bug database</a> and submit a bug if |
Chris Lattner | 5eccca4 | 2003-12-12 21:22:16 +0000 | [diff] [blame] | 295 | there isn't already one.</p> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 296 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 297 | </div> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 298 | |
Chris Lattner | f5ee170 | 2004-03-14 02:03:02 +0000 | [diff] [blame] | 299 | <!-- ======================================================================= --> |
| 300 | <div class="doc_subsection"> |
| 301 | <a name="experimental">Experimental features included with this release</a> |
| 302 | </div> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 303 | |
Chris Lattner | f5ee170 | 2004-03-14 02:03:02 +0000 | [diff] [blame] | 304 | <div class="doc_text"> |
| 305 | |
Misha Brukman | 6df9e2c | 2004-05-12 21:46:05 +0000 | [diff] [blame] | 306 | <p>The following components of this LLVM release are either untested, known to |
| 307 | be broken or unreliable, or are in early development. These components should |
| 308 | not be relied on, and bugs should not be filed against them, but they may be |
| 309 | useful to some people. In particular, if you would like to work on one of these |
Chris Lattner | 49e693e | 2006-08-09 04:08:52 +0000 | [diff] [blame] | 310 | components, please contact us on the <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev list</a>.</p> |
Chris Lattner | f5ee170 | 2004-03-14 02:03:02 +0000 | [diff] [blame] | 311 | |
| 312 | <ul> |
Chris Lattner | 44c933e | 2006-04-18 06:18:36 +0000 | [diff] [blame] | 313 | <li>The <tt>-cee</tt> pass is known to be buggy, and may be removed in in a |
| 314 | future release.</li> |
Chris Lattner | 57a460e | 2007-05-23 04:39:32 +0000 | [diff] [blame] | 315 | <li>C++ EH support is disabled for this release.</li> |
| 316 | <li>The MSIL backend is experimental.</li> |
Chris Lattner | 58504a6 | 2006-02-05 06:39:36 +0000 | [diff] [blame] | 317 | <li>The IA64 code generator is experimental.</li> |
Chris Lattner | c463b27 | 2005-10-29 07:07:09 +0000 | [diff] [blame] | 318 | <li>The Alpha JIT is experimental.</li> |
Chris Lattner | 44c933e | 2006-04-18 06:18:36 +0000 | [diff] [blame] | 319 | <li>"<tt>-filetype=asm</tt>" (the default) is the only supported value for the |
| 320 | <tt>-filetype</tt> llc option.</li> |
Chris Lattner | f5ee170 | 2004-03-14 02:03:02 +0000 | [diff] [blame] | 321 | </ul> |
| 322 | |
| 323 | </div> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 324 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 325 | <!-- ======================================================================= --> |
| 326 | <div class="doc_subsection"> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 327 | <a name="x86-be">Known problems with the X86 back-end</a> |
John Criswell | c0c186d | 2005-11-08 21:11:33 +0000 | [diff] [blame] | 328 | </div> |
| 329 | |
| 330 | <div class="doc_text"> |
| 331 | |
| 332 | <ul> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 333 | <li>The X86 backend does not yet support <a href="http://llvm.org/PR879">inline |
Chris Lattner | caf0634 | 2007-05-09 04:58:11 +0000 | [diff] [blame] | 334 | assembly that uses the X86 floating point stack</a>.</li> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 335 | </ul> |
| 336 | |
| 337 | </div> |
| 338 | |
| 339 | <!-- ======================================================================= --> |
| 340 | <div class="doc_subsection"> |
| 341 | <a name="ppc-be">Known problems with the PowerPC back-end</a> |
| 342 | </div> |
| 343 | |
| 344 | <div class="doc_text"> |
| 345 | |
| 346 | <ul> |
| 347 | <li><a href="http://llvm.org/PR642">PowerPC backend does not correctly |
| 348 | implement ordered FP comparisons</a>.</li> |
Nicolas Geoffray | e4285dc | 2007-05-15 09:21:28 +0000 | [diff] [blame] | 349 | <li>The Linux PPC32/ABI support needs testing for the interpreter and static |
Chris Lattner | 57a460e | 2007-05-23 04:39:32 +0000 | [diff] [blame] | 350 | compilation, and lacks support for debug information.</li> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 351 | </ul> |
| 352 | |
| 353 | </div> |
| 354 | |
| 355 | <!-- ======================================================================= --> |
| 356 | <div class="doc_subsection"> |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 357 | <a name="arm-be">Known problems with the ARM back-end</a> |
| 358 | </div> |
| 359 | |
| 360 | <div class="doc_text"> |
| 361 | |
| 362 | <ul> |
Chris Lattner | 57a460e | 2007-05-23 04:39:32 +0000 | [diff] [blame] | 363 | <li>Thumb mode works only on ARMv6 or higher processors. On sub-ARMv6 |
| 364 | processors, thumb program can crash or produces wrong |
| 365 | results (<a href="http://llvm.org/PR1388">PR1388</a>).</li> |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 366 | <li>Compilation for ARM Linux OABI (old ABI) is supported, but not fully tested. |
| 367 | </li> |
Chris Lattner | 57a460e | 2007-05-23 04:39:32 +0000 | [diff] [blame] | 368 | <li>There is a bug in QEMU-ARM (<= 0.9.0) which causes it to incorrectly execute |
| 369 | programs compiled with LLVM. Please use more recent versions of QEMU.</li> |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 370 | </ul> |
| 371 | |
| 372 | </div> |
| 373 | |
| 374 | <!-- ======================================================================= --> |
| 375 | <div class="doc_subsection"> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 376 | <a name="sparc-be">Known problems with the SPARC back-end</a> |
| 377 | </div> |
| 378 | |
| 379 | <div class="doc_text"> |
| 380 | |
| 381 | <ul> |
| 382 | <li>The SPARC backend only supports the 32-bit SPARC ABI (-m32), it does not |
| 383 | support the 64-bit SPARC ABI (-m64).</li> |
| 384 | </ul> |
| 385 | |
| 386 | </div> |
| 387 | |
| 388 | <!-- ======================================================================= --> |
| 389 | <div class="doc_subsection"> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 390 | <a name="alpha-be">Known problems with the Alpha back-end</a> |
| 391 | </div> |
| 392 | |
| 393 | <div class="doc_text"> |
| 394 | |
| 395 | <ul> |
| 396 | |
| 397 | <li>On 21164s, some rare FP arithmetic sequences which may trap do not have the |
| 398 | appropriate nops inserted to ensure restartability.</li> |
| 399 | |
John Criswell | c0c186d | 2005-11-08 21:11:33 +0000 | [diff] [blame] | 400 | </ul> |
| 401 | </div> |
| 402 | |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 403 | <!-- ======================================================================= --> |
| 404 | <div class="doc_subsection"> |
| 405 | <a name="ia64-be">Known problems with the IA64 back-end</a> |
| 406 | </div> |
| 407 | |
| 408 | <div class="doc_text"> |
| 409 | |
| 410 | <ul> |
| 411 | |
| 412 | <li>C++ programs are likely to fail on IA64, as calls to <tt>setjmp</tt> are |
| 413 | made where the argument is not 16-byte aligned, as required on IA64. (Strictly |
| 414 | speaking this is not a bug in the IA64 back-end; it will also be encountered |
| 415 | when building C++ programs using the C back-end.)</li> |
| 416 | |
| 417 | <li>The C++ front-end does not use <a href="http://llvm.org/PR406">IA64 |
| 418 | ABI compliant layout of v-tables</a>. In particular, it just stores function |
| 419 | pointers instead of function descriptors in the vtable. This bug prevents |
| 420 | mixing C++ code compiled with LLVM with C++ objects compiled by other C++ |
| 421 | compilers.</li> |
| 422 | |
| 423 | <li>There are a few ABI violations which will lead to problems when mixing LLVM |
| 424 | output with code built with other compilers, particularly for floating-point |
| 425 | programs.</li> |
| 426 | |
| 427 | <li>Defining vararg functions is not supported (but calling them is ok).</li> |
| 428 | |
Chris Lattner | caf0634 | 2007-05-09 04:58:11 +0000 | [diff] [blame] | 429 | <li>The Itanium backend has bitrotted somewhat.</li> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 430 | </ul> |
| 431 | |
| 432 | </div> |
| 433 | |
| 434 | <!-- ======================================================================= --> |
| 435 | <div class="doc_subsection"> |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 436 | <a name="c-be">Known problems with the C back-end</a> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 437 | </div> |
| 438 | |
| 439 | <div class="doc_text"> |
| 440 | |
| 441 | <ul> |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 442 | <li><a href="http://llvm.org/PR802">The C backend does not support inline |
| 443 | assembly code</a>.</li> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 444 | </ul> |
| 445 | |
| 446 | </div> |
John Criswell | c0c186d | 2005-11-08 21:11:33 +0000 | [diff] [blame] | 447 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 448 | |
| 449 | <!-- ======================================================================= --> |
| 450 | <div class="doc_subsection"> |
| 451 | <a name="c-fe">Known problems with the C front-end</a> |
| 452 | </div> |
Chris Lattner | 47588f9 | 2003-10-02 05:07:23 +0000 | [diff] [blame] | 453 | |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 454 | <!-- _______________________________________________________________________ --> |
Chris Lattner | b40efb3 | 2003-12-14 05:03:43 +0000 | [diff] [blame] | 455 | <div class="doc_subsubsection">Bugs</div> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 456 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 457 | <div class="doc_text"> |
Chris Lattner | c5d658a | 2006-03-03 00:34:26 +0000 | [diff] [blame] | 458 | |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 459 | <p>llvm-gcc4 does not currently support <a href="http://llvm.org/PR869">Link-Time |
| 460 | Optimization</a> on most platforms "out-of-the-box". Please inquire on the |
| 461 | llvmdev mailing list if you are interested.</p> |
Chris Lattner | d9ea017 | 2006-08-08 17:27:28 +0000 | [diff] [blame] | 462 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 463 | </div> |
| 464 | |
| 465 | <!-- _______________________________________________________________________ --> |
| 466 | <div class="doc_subsubsection"> |
| 467 | Notes |
| 468 | </div> |
| 469 | |
| 470 | <div class="doc_text"> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 471 | <ul> |
| 472 | |
Chris Lattner | d09c4ec | 2007-05-17 22:02:24 +0000 | [diff] [blame] | 473 | <li><p>"long double" is silently transformed by the front-end into "double". There |
| 474 | is no support for floating point data types of any size other than 32 and 64 |
| 475 | bits.</p></li> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 476 | |
Chris Lattner | d09c4ec | 2007-05-17 22:02:24 +0000 | [diff] [blame] | 477 | <li><p>llvm-gcc does <b>not</b> support <tt>__builtin_apply</tt> yet. |
| 478 | See <a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</p> |
| 479 | </li> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 480 | |
Duncan Sands | 32a8344 | 2007-05-18 09:04:20 +0000 | [diff] [blame] | 481 | <li><p>llvm-gcc <b>partially</b> supports these GCC extensions:</p> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 482 | <ol> |
Chris Lattner | d09c4ec | 2007-05-17 22:02:24 +0000 | [diff] [blame] | 483 | <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.<br> |
| 484 | Nested functions are supported, but llvm-gcc does not support non-local |
| 485 | gotos or taking the address of a nested function.</li> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 486 | |
| 487 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html#Function%20Attributes">Function Attributes</a>: |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 488 | |
John Criswell | d000e1d | 2003-12-18 16:43:17 +0000 | [diff] [blame] | 489 | Declaring that functions have no side effects or that they can never |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 490 | return.<br> |
| 491 | |
Chris Lattner | d09c4ec | 2007-05-17 22:02:24 +0000 | [diff] [blame] | 492 | <b>Supported:</b> <tt>alias</tt>, <tt>always_inline</tt>, <tt>cdecl</tt>, |
| 493 | <tt>constructor</tt>, <tt>destructor</tt>, |
Anton Korobeynikov | 9413de3 | 2006-11-18 08:04:48 +0000 | [diff] [blame] | 494 | <tt>deprecated</tt>, <tt>fastcall</tt>, <tt>format</tt>, |
Anton Korobeynikov | 9ec8137 | 2007-05-10 08:26:24 +0000 | [diff] [blame] | 495 | <tt>format_arg</tt>, <tt>non_null</tt>, <tt>noreturn</tt>, <tt>regparm</tt> |
Anton Korobeynikov | 8cea37b | 2007-01-23 12:35:46 +0000 | [diff] [blame] | 496 | <tt>section</tt>, <tt>stdcall</tt>, <tt>unused</tt>, <tt>used</tt>, |
| 497 | <tt>visibility</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 498 | |
Chris Lattner | d09c4ec | 2007-05-17 22:02:24 +0000 | [diff] [blame] | 499 | <b>Ignored:</b> <tt>noinline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>, |
| 500 | <tt>malloc</tt>, <tt>no_instrument_function</tt></li> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 501 | </ol> |
Chris Lattner | d09c4ec | 2007-05-17 22:02:24 +0000 | [diff] [blame] | 502 | </li> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 503 | |
Chris Lattner | d09c4ec | 2007-05-17 22:02:24 +0000 | [diff] [blame] | 504 | <li><p>llvm-gcc supports the vast majority of GCC extensions, including:</p> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 505 | |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 506 | <ol> |
Chris Lattner | d09c4ec | 2007-05-17 22:02:24 +0000 | [diff] [blame] | 507 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Pragmas.html#Pragmas">Pragmas</a>: Pragmas accepted by GCC.</li> |
| 508 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Local-Labels.html#Local%20Labels">Local Labels</a>: Labels local to a block.</li> |
| 509 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>: |
| 510 | Other built-in functions.</li> |
| 511 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>: |
| 512 | Specifying attributes of variables.</li> |
| 513 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Type-Attributes.html#Type%20Attributes">Type Attributes</a>: Specifying attributes of types.</li> |
| 514 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread_002dLocal.html">Thread-Local</a>: Per-thread variables.</li> |
| 515 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>: |
| 516 | Arrays whose length is computed at run time.</li> |
Chris Lattner | 7fe97dd | 2004-03-16 08:54:07 +0000 | [diff] [blame] | 517 | <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 | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 518 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li> |
| 519 | <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 | ca26c3e | 2004-06-22 03:48:17 +0000 | [diff] [blame] | 520 | <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 | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 521 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li> |
| 522 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li> |
| 523 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li> |
| 524 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li> |
| 525 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li> |
| 526 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li> |
| 527 | <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> |
| 528 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 529 | <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> |
| 530 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constraints.html#Constraints">Constraints</a>: Constraints for asm operands.</li> |
| 531 | <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> |
| 532 | <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> |
| 533 | <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> |
| 534 | <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> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 535 | <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 | c4b7bee | 2003-12-12 04:37:31 +0000 | [diff] [blame] | 536 | <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 | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 537 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Initializers.html#Initializers">Initializers</a>: Non-constant initializers.</li> |
John Criswell | d000e1d | 2003-12-18 16:43:17 +0000 | [diff] [blame] | 538 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions, |
| 539 | or arrays as values.</li> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 540 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Designated-Inits.html#Designated%20Inits">Designated Inits</a>: Labeling elements of initializers.</li> |
Misha Brukman | c4b7bee | 2003-12-12 04:37:31 +0000 | [diff] [blame] | 541 | <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 | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 542 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li> |
| 543 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li> |
| 544 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li> |
Tanya Lattner | 78537e4 | 2004-12-08 18:29:38 +0000 | [diff] [blame] | 545 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C_002b_002b-Comments.html#C_002b_002b-Comments">C++ Comments</a>: C++ comments are recognized.</li> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 546 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li> |
| 547 | <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> |
| 548 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li> |
| 549 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li> |
| 550 | <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> |
| 551 | <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> |
| 552 | <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 | 25795bc | 2004-02-14 04:08:29 +0000 | [diff] [blame] | 553 | <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 | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 554 | <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> |
| 555 | <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Attribute-Syntax.html#Attribute%20Syntax">Attribute Syntax</a>: Formal syntax for attributes.</li> |
Misha Brukman | e0c891c | 2003-11-22 01:00:11 +0000 | [diff] [blame] | 556 | </ol></li> |
| 557 | |
| 558 | </ul> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 559 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 560 | <p>If you run into GCC extensions which have not been included in any of these |
| 561 | lists, please let us know (also including whether or not they work).</p> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 562 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 563 | </div> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 564 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 565 | <!-- ======================================================================= --> |
| 566 | <div class="doc_subsection"> |
| 567 | <a name="c++-fe">Known problems with the C++ front-end</a> |
| 568 | </div> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 569 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 570 | <div class="doc_text"> |
| 571 | |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 572 | <p>The C++ front-end is considered to be fully |
Chris Lattner | 7506b1d | 2004-12-07 08:04:13 +0000 | [diff] [blame] | 573 | tested and works for a number of non-trivial programs, including LLVM |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 574 | itself, Qt, Mozilla, etc.</p> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 575 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 576 | <ul> |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 577 | <li>llvm-gcc4 only has partial support for <a href="http://llvm.org/PR870">C++ |
| 578 | Exception Handling</a>, and it is not enabled by default.</li> |
| 579 | |
| 580 | <!-- NO EH Support! |
Chris Lattner | e01fcfb | 2003-10-27 18:30:37 +0000 | [diff] [blame] | 581 | |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 582 | <li>Destructors for local objects are not always run when a <tt>longjmp</tt> is |
Chris Lattner | 1909261 | 2003-10-02 16:38:05 +0000 | [diff] [blame] | 583 | performed. In particular, destructors for objects in the <tt>longjmp</tt>ing |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 584 | function and in the <tt>setjmp</tt> receiver function may not be run. |
John Criswell | d000e1d | 2003-12-18 16:43:17 +0000 | [diff] [blame] | 585 | Objects in intervening stack frames will be destroyed, however (which is |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 586 | better than most compilers).</li> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 587 | |
Chris Lattner | 1909261 | 2003-10-02 16:38:05 +0000 | [diff] [blame] | 588 | <li>The LLVM C++ front-end follows the <a |
| 589 | href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>. |
| 590 | This document, which is not Itanium specific, specifies a standard for name |
| 591 | mangling, class layout, v-table layout, RTTI formats, and other C++ |
| 592 | representation issues. Because we use this API, code generated by the LLVM |
| 593 | compilers should be binary compatible with machine code generated by other |
| 594 | Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc). |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 595 | <i>However</i>, the exception handling mechanism used by llvm-gcc3 is very |
Chris Lattner | 1909261 | 2003-10-02 16:38:05 +0000 | [diff] [blame] | 596 | different from the model used in the Itanium ABI, so <b>exceptions will not |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 597 | interact correctly</b>. </li> |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 598 | --> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 599 | </ul> |
Chris Lattner | fcc54b3 | 2003-10-07 22:14:37 +0000 | [diff] [blame] | 600 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 601 | </div> |
| 602 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 603 | |
Chris Lattner | 98a493c | 2005-05-15 16:01:20 +0000 | [diff] [blame] | 604 | |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 605 | <!-- *********************************************************************** --> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 606 | <div class="doc_section"> |
| 607 | <a name="additionalinfo">Additional Information</a> |
| 608 | </div> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 609 | <!-- *********************************************************************** --> |
| 610 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 611 | <div class="doc_text"> |
| 612 | |
Chris Lattner | 416db10 | 2005-05-16 17:13:10 +0000 | [diff] [blame] | 613 | <p>A wide variety of additional information is available on the <a |
Chris Lattner | b4b0ce7 | 2007-05-18 00:44:29 +0000 | [diff] [blame] | 614 | href="http://llvm.org">LLVM web page</a>, in particular in the <a |
| 615 | href="http://llvm.org/docs/">documentation</a> section. The web page also |
Reid Spencer | 669ed45 | 2007-07-09 08:04:31 +0000 | [diff] [blame] | 616 | contains versions of the API documentation which is up-to-date with the |
| 617 | Subversion version of the source code. |
Misha Brukman | 109d9e8 | 2005-03-30 19:14:24 +0000 | [diff] [blame] | 618 | You can access versions of these documents specific to this release by going |
| 619 | into the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 620 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 621 | <p>If you have any questions or comments about LLVM, please feel free to contact |
Chris Lattner | c463b27 | 2005-10-29 07:07:09 +0000 | [diff] [blame] | 622 | us via the <a href="http://llvm.org/docs/#maillist"> mailing |
Chris Lattner | 5eccca4 | 2003-12-12 21:22:16 +0000 | [diff] [blame] | 623 | lists</a>.</p> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 624 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 625 | </div> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 626 | |
| 627 | <!-- *********************************************************************** --> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 628 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 629 | <hr> |
Misha Brukman | 2061e89 | 2003-11-22 01:23:39 +0000 | [diff] [blame] | 630 | <address> |
Misha Brukman | 38847d5 | 2003-12-21 22:53:21 +0000 | [diff] [blame] | 631 | <a href="http://jigsaw.w3.org/css-validator/check/referer"><img |
Misha Brukman | 2061e89 | 2003-11-22 01:23:39 +0000 | [diff] [blame] | 632 | src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a> |
| 633 | <a href="http://validator.w3.org/check/referer"><img |
| 634 | src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a> |
| 635 | |
Chris Lattner | b4b0ce7 | 2007-05-18 00:44:29 +0000 | [diff] [blame] | 636 | <a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 637 | Last modified: $Date$ |
Misha Brukman | 2061e89 | 2003-11-22 01:23:39 +0000 | [diff] [blame] | 638 | </address> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 639 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 640 | </body> |
| 641 | </html> |