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gerrit-public.fairphone.software / fp2-dev / platform / external / llvm / bad10eebbe00e6fd72fb4f34daecf28dac6791e6 / . / docs / ReleaseNotes.html
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Misha Brukman500bc302003-11-22 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 Spencer6454ed32004-11-18 18:38:58 +0000[diff] [blame]5 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]6 <link rel="stylesheet" href="llvm.css" type="text/css">
Chris Lattner78bf32b2004-12-09 22:22:58 +0000[diff] [blame]7 <title>LLVM 1.5 Release Notes</title>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]8</head>
9<body>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]10
Chris Lattner78bf32b2004-12-09 22:22:58 +0000[diff] [blame]11<div class="doc_title">LLVM 1.5 Release Notes</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]12
13<ol>
Misha Brukman500bc302003-11-22 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 Lattner4b538b92004-04-30 22:17:12 +0000[diff] [blame]16 <li><a href="GettingStarted.html">Installation Instructions</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]17 <li><a href="#portability">Portability and Supported Platforms</a></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]18 <li><a href="#knownproblems">Known Problems</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]19 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]20</ol>
21
Chris Lattner7911ce22004-05-23 21:07:27 +0000[diff] [blame]22<div class="doc_author">
Chris Lattner78bf32b2004-12-09 22:22:58 +0000[diff] [blame]23 <p>Written by the <a href="http://llvm.cs.uiuc.edu">LLVM Team</a><p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]24</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]25
26<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]27<div class="doc_section">
28 <a name="intro">Introduction</a>
29</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]30<!-- *********************************************************************** -->
31
Misha Brukman500bc302003-11-22 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 Lattner78bf32b2004-12-09 22:22:58 +0000[diff] [blame]35infrastructure, release 1.5. Here we describe the status of LLVM, including any
Chris Lattner7506b1d2004-12-07 08:04:13 +0000[diff] [blame]36known problems and improvements from the previous release. The most up-to-date
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]37version of this document can be found on the <a
Chris Lattner78bf32b2004-12-09 22:22:58 +0000[diff] [blame]38href="http://llvm.cs.uiuc.edu/releases/1.5/">LLVM 1.5 web site</a>. If you are
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]39not reading this on the LLVM web pages, you should probably go there because
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]40this document may be updated after the release.</p>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]41
Chris Lattner7506b1d2004-12-07 08:04:13 +0000[diff] [blame]42<p>For more information about LLVM, including information about the latest
43release, please check out the <a href="http://llvm.cs.uiuc.edu">main LLVM
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]44web site</a>. If you have questions or comments, the <a
45href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM developer's mailing
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]46list</a> is a good place to send them.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]47
Chris Lattner78bf32b2004-12-09 22:22:58 +0000[diff] [blame]48<p>Note that if you are reading this file from CVS or the main LLVM web page,
49this document applies to the <i>next</i> release, not the current one. To see
50the release notes for the current or previous releases, see the <a
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]51href="http://llvm.cs.uiuc.edu/releases/">releases page</a>.</p>
52
53</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]54
55<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]56<div class="doc_section">
57 <a name="whatsnew">What's New?</a>
58</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]59<!-- *********************************************************************** -->
60
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]61<div class="doc_text">
62
Chris Lattner78bf32b2004-12-09 22:22:58 +0000[diff] [blame]63<p>This is the sixth public release of the LLVM compiler infrastructure.</p>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]64
Chris Lattner0bce6ac2004-12-10 16:27:34 +0000[diff] [blame]65<p> At this time, LLVM is known to correctly compile a broad range of C and
Chris Lattner78bf32b2004-12-09 22:22:58 +0000[diff] [blame]66C++ programs, including the SPEC CPU95 &amp; 2000 suite. TODO. It also includes
67bug fixes for those problems found since the 1.4 release.</p>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]68
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]69</div>
70
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]71<!--=========================================================================-->
72<div class="doc_subsubsection">
Chris Lattnera39719f2004-02-25 16:36:51 +0000[diff] [blame]73<a name="newfeatures">This release implements the following new features:</a>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]74</div>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]75
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]76<div class="doc_text">
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]77<ol>
Chris Lattner74d74cd2004-12-11 06:10:52 +0000[diff] [blame]78 <li>LLVM now includes an <a href="http://llvm.cs.uiuc.edu/PR415">
Chris Lattnerda1f03c2005-01-22 18:45:35 +0000[diff] [blame]79 Interprocedural Sparse Conditional Constant Propagation</a> pass, named
Chris Lattner74d74cd2004-12-11 06:10:52 +0000[diff] [blame]80 -ipsccp, which is run by default at link-time.</li>
Chris Lattner75008d82005-02-01 01:33:52 +0000[diff] [blame]81 <li>LLVM 1.5 is now about 15% faster than LLVM 1.4 and its core data structures
Chris Lattner2e12c742005-02-13 22:27:24 +0000[diff] [blame]82 use about 30% less memory.</li>
Misha Brukman89976ff2005-03-18 00:48:56 +0000[diff] [blame]83 <li>LLVM includes new experimental native code generators for SparcV8,
84 Alpha, and IA64.</li>
Chris Lattner2e12c742005-02-13 22:27:24 +0000[diff] [blame]85 <li>Support for Microsoft Visual Studio is improved, and <a
Chris Lattnera5d803e2005-02-14 22:58:38 +0000[diff] [blame]86 href="GettingStartedVS.html">now documented</a>.</li>
Reid Spencer2ebdb532005-04-22 20:27:33 +0000[diff] [blame]87 <li>Configuring LLVM to build targets selectively is now implemented, via the
88 <tt>--enable-targets=</tt> option. This feature is documented
89 <a href="GettingStarted.html#config">here</a>.</li>
Chris Lattner55ee0312003-11-19 22:05:38 +0000[diff] [blame]90</ol>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]91
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]92</div>
93
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]94
95<!--=========================================================================-->
96<div class="doc_subsubsection">
97In this release, the following missing features were implemented:
98</div>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]99
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]100<div class="doc_text">
101
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]102<ol>
Chris Lattnerd7934542005-02-28 16:52:28 +0000[diff] [blame]103 <li>LLVM can now create native shared libraries with '<tt>llvm-gcc ...
104 -shared -Wl,-native</tt>' (or with <tt>-Wl,-native-cbe</tt>).</li>
Chris Lattnerd03b3bc2005-03-11 06:16:26 +0000[diff] [blame]105 <li>LLVM now supports a new "<a href="LangRef.html#i_prefetch">llvm.prefetch
106 </a>" intrinsic, and llvm-gcc now supports __builtin_prefetch.
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]107</ol>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]108
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]109</div>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]110
111<!--=========================================================================-->
112<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]113<a name="qualityofimp">In this release, the following Quality of Implementation
114issues were fixed:</a>
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]115</div>
116
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]117<div class="doc_text">
118
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]119<ol>
Chris Lattnerda1f03c2005-01-22 18:45:35 +0000[diff] [blame]120 <li><a href="http://llvm.cs.uiuc.edu/PR448">Building LLVM in optimized mode
121 should no longer cause GCC to hit swap in the PowerPC backend.</a></li>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]122</ol>
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]123</div>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]124
125<!--=========================================================================-->
126<div class="doc_subsubsection">
Chris Lattner6e1ef192004-05-02 04:19:15 +0000[diff] [blame]127<a name="codequality">This release includes the following Code Quality
128improvements:</a>
Chris Lattneraab56d42004-05-23 20:42:08 +0000[diff] [blame]129</div>
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]130
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]131<div class="doc_text">
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]132<ol>
Andrew Lenharth30a1f8f2005-05-03 16:59:09 +0000[diff] [blame]133 <li>Transition code for 1.0 style varargs was removed. </li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]134</ol>
Reid Spencer8e0262f2004-05-23 17:23:13 +0000[diff] [blame]135</div>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]136
137<!--=========================================================================-->
138<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]139<a name="bugfix">In this release, the following bugs in the previous release
140were fixed:</a>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]141</div>
142
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]143<div class="doc_text">
144
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]145
Chris Lattnerf54e9cb2005-02-14 16:57:55 +0000[diff] [blame]146<p>Bugs fixed in the LLVM Core:</p>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]147<ol>
Chris Lattnerbfd24682004-12-29 04:39:50 +0000[diff] [blame]148 <li><a href="http://llvm.cs.uiuc.edu/PR491">[dse] DSE deletes stores that
149 are partially overwritten by smaller stores</a></li>
Chris Lattnerf79e57e2005-04-19 06:08:04 +0000[diff] [blame]150 <li><a href="http://llvm.cs.uiuc.edu/PR548">[instcombine] miscompilation of
151 setcc or setcc in one case</a></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]152</ol>
153
Chris Lattnerf54e9cb2005-02-14 16:57:55 +0000[diff] [blame]154<p>Code Generator Bugs:</p>
155<ol>
156 <li><a href="http://llvm.cs.uiuc.edu/PR490">[cbackend] Logical constant
157 expressions (and/or/xor) not implemented</a></li>
158 <li><a href="http://llvm.cs.uiuc.edu/PR511">[cbackend] C backend does not
159 respect 'volatile'</a></li>
160</ol>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]161
Chris Lattnerf54e9cb2005-02-14 16:57:55 +0000[diff] [blame]162<p>Bugs in the C/C++ front-end:</p>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]163<ol>
Chris Lattner8de9f232005-01-03 04:20:21 +0000[diff] [blame]164 <li><a href="http://llvm.cs.uiuc.edu/PR487">[llvmgcc] llvm-gcc incorrectly
165 rejects some constant initializers involving the addresses of array
166 elements</a></li>
Chris Lattnerf832f6a2005-02-11 19:29:52 +0000[diff] [blame]167 <li><a href="http://llvm.cs.uiuc.edu/PR501">[llvm-g++] Crash compiling
168 anonymous union</a></li>
Chris Lattnerf54e9cb2005-02-14 16:57:55 +0000[diff] [blame]169 <li><a href="http://llvm.cs.uiuc.edu/PR509">[llvm-g++] Do not use dynamic
170 initialization where static init will do</a></li>
Chris Lattner4a9dc292005-02-15 05:28:06 +0000[diff] [blame]171 <li><a href="http://llvm.cs.uiuc.edu/PR510">[llvmgcc] Field offset
172 miscalculated for some structure fields following bit fields</a></li>
Chris Lattner5ad907a2005-02-15 07:02:12 +0000[diff] [blame]173 <li><a href="http://llvm.cs.uiuc.edu/PR513">[llvm-g++] Temporary lifetimes
174 incorrect for short circuit logical operations</a></li>
Chris Lattnerc1f90a92005-02-19 07:29:25 +0000[diff] [blame]175 <li><a href="http://llvm.cs.uiuc.edu/PR517">[llvm-gcc] Crash compiling
176 bitfield &lt;-&gt; aggregate assignment</a></li>
Chris Lattner94f6ac72005-02-19 17:13:20 +0000[diff] [blame]177 <li><a href="http://llvm.cs.uiuc.edu/PR520">[llvm-g++] Error compiling
Chris Lattnerd12b9b22005-02-19 17:17:32 +0000[diff] [blame]178 virtual function thunk with an unnamed argument</a></li>
Chris Lattner290d2292005-02-20 23:31:49 +0000[diff] [blame]179 <li><a href="http://llvm.cs.uiuc.edu/PR522">[llvm-gcc] Crash on certain
180 C99 complex number routines</a></li>
Chris Lattner2a3cdf72005-02-27 19:31:02 +0000[diff] [blame]181 <li><a href="http://llvm.cs.uiuc.edu/PR529">[llvm-g++] Crash using placement
182 new on an array type</a></li>
Brian Gaekee77c8e72004-08-24 07:43:48 +0000[diff] [blame]183</ol>
184
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]185</div>
Reid Spencer8e0262f2004-05-23 17:23:13 +0000[diff] [blame]186
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]187<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]188<div class="doc_section">
189 <a name="portability">Portability and Supported Platforms</a>
190</div>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]191<!-- *********************************************************************** -->
192
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]193<div class="doc_text">
194
John Criswell0b5b5e92004-12-08 20:35:47 +0000[diff] [blame]195<p>LLVM is known to work on the following platforms:</p>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]196
197<ul>
198<li>Intel and AMD machines running Red Hat Linux and FreeBSD (and probably
199 other unix-like systems).</li>
200<li>Sun UltraSPARC workstations running Solaris 8.</li>
Chris Lattner7506b1d2004-12-07 08:04:13 +0000[diff] [blame]201<li>Intel and AMD machines running on Win32 with the Cygwin libraries (limited
202 support is available for native builds with Visual C++).</li>
203<li>PowerPC-based Mac OS X systems, running 10.2 and above.</li>
Andrew Lenharth30a1f8f2005-05-03 16:59:09 +0000[diff] [blame]204<li>Alpha-based machines running Debian GNU/Linux</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]205</ul>
206
Brian Gaekeb0fd7612004-05-09 05:28:35 +0000[diff] [blame]207<p>The core LLVM infrastructure uses
208<a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself
209to the machine and operating system on which it is built. However, minor
210porting may be required to get LLVM to work on new platforms. We welcome your
211portability patches and reports of successful builds or error messages.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]212
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]213</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]214
215<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]216<div class="doc_section">
217 <a name="knownproblems">Known Problems</a>
218</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]219<!-- *********************************************************************** -->
220
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]221<div class="doc_text">
222
223<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]224component. As new problems are discovered, they will be added to these
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]225sections. If you run into a problem, please check the <a
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]226href="http://llvm.cs.uiuc.edu/bugs/">LLVM bug database</a> and submit a bug if
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]227there isn't already one.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]228
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]229</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]230
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]231<!-- ======================================================================= -->
232<div class="doc_subsection">
233 <a name="experimental">Experimental features included with this release</a>
234</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]235
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]236<div class="doc_text">
237
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]238<p>The following components of this LLVM release are either untested, known to
239be broken or unreliable, or are in early development. These components should
240not be relied on, and bugs should not be filed against them, but they may be
241useful to some people. In particular, if you would like to work on one of these
242components, please contact us on the llvmdev list.</p>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]243
244<ul>
Chris Lattner7506b1d2004-12-07 08:04:13 +0000[diff] [blame]245<li>The following passes are incomplete or buggy, and may be removed in future
Chris Lattner1fe848e2005-01-28 06:13:52 +0000[diff] [blame]246 releases: <tt>-cee, -branch-combine, -instloops, -paths, -pre</tt></li>
Chris Lattner7506b1d2004-12-07 08:04:13 +0000[diff] [blame]247<li>The <tt>llvm-db</tt> tool is in a very early stage of development, but can
248 be used to step through programs and inspect the stack.</li>
Misha Brukman109d9e82005-03-30 19:14:24 +0000[diff] [blame]249<li>The "iterative scan" register allocator (enabled with
250 <tt>-regalloc=iterativescan</tt>) is not stable.</li>
Misha Brukman89976ff2005-03-18 00:48:56 +0000[diff] [blame]251<li>The SparcV8, Alpha, and IA64 ports are experimental.</li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]252</ul>
253
254</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]255
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]256<!-- ======================================================================= -->
257<div class="doc_subsection">
258 <a name="core">Known problems with the LLVM Core</a>
259</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]260
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]261<div class="doc_text">
262
263<ul>
Misha Brukman109d9e82005-03-30 19:14:24 +0000[diff] [blame]264 <li>In the JIT, <tt>dlsym()</tt> on a symbol compiled by the JIT will not
265 work.</li>
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame]266 <li>The JIT does not use mutexes to protect its internal data structures. As
267 such, execution of a threaded program could cause these data structures to be
268 corrupted.
269 </li>
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame]270 <li><a href="http://llvm.cs.uiuc.edu/PR240">The lower-invoke pass does not
271 mark values live across a setjmp as volatile</a>. This missing feature
272 only affects targets whose setjmp/longjmp libraries do not save and restore
273 the entire register file.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]274</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]275</div>
276
277<!-- ======================================================================= -->
278<div class="doc_subsection">
279 <a name="c-fe">Known problems with the C front-end</a>
280</div>
Chris Lattner47588f92003-10-02 05:07:23 +0000[diff] [blame]281
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]282<!-- _______________________________________________________________________ -->
Chris Lattnerb40efb32003-12-14 05:03:43 +0000[diff] [blame]283<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]284
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]285<div class="doc_text">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]286<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]287<li>C99 Variable sized arrays do not release stack memory when they go out of
288 scope. Thus, the following program may run out of stack space:
289<pre>
290 for (i = 0; i != 1000000; ++i) {
291 int X[n];
292 foo(X);
293 }
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]294</pre></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]295
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]296<li>Initialization of global union variables can only be done <a
Misha Brukman43ee2932004-12-04 00:45:09 +0000[diff] [blame]297href="http://llvm.cs.uiuc.edu/PR162">with the largest union member</a>.</li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]298
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]299</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]300</div>
301
302<!-- _______________________________________________________________________ -->
303<div class="doc_subsubsection">
304 Notes
305</div>
306
307<div class="doc_text">
308
309<ul>
310
311<li>Inline assembly is not yet supported.</li>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]312
313<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]314support for floating point data types of any size other than 32 and 64
315bits.</li>
316
317<li>The following Unix system functionality has not been tested and may not
318work:
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]319 <ol>
320 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
321 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
322 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
323 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
324 - These functions have not been tested.
325 </ol></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]326
327<li>Although many GCC extensions are supported, some are not. In particular,
328 the following extensions are known to <b>not be</b> supported:
329 <ol>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]330 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Local-Labels.html#Local%20Labels">Local Labels</a>: Labels local to a block.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]331 <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>
332 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
333 <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 Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]334 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constraints.html#Constraints">Constraints</a>: Constraints for asm operands.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]335 <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>
336 <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 Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]337 <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>
338 <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>
Tanya Lattner014e5f52004-12-08 18:25:34 +0000[diff] [blame]339 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread_002dLocal.html">Thread-Local</a>: Per-thread variables.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]340 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Pragmas.html#Pragmas">Pragmas</a>: Pragmas accepted by GCC.</li>
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]341 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]342
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]343 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]344 attribute means that the LLVM compiler ignores the presence of the attribute,
345 but the code should still work. An unsupported attribute is one which is
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]346 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]347 the program.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]348
349 <ol>
350 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
351 Arrays whose length is computed at run time.<br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]352 Supported, but allocated stack space is not freed until the function returns (noted above).</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]353
354 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html#Function%20Attributes">Function Attributes</a>:
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]355
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]356 Declaring that functions have no side effects or that they can never
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]357 return.<br>
358
359 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
John Criswell0b5b5e92004-12-08 20:35:47 +0000[diff] [blame]360 <tt>noreturn</tt>, <tt>constructor</tt>, <tt>destructor</tt>,
361 <tt>unused</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]362 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
363
John Criswell0b5b5e92004-12-08 20:35:47 +0000[diff] [blame]364 <b>Ignored:</b> <tt>noinline</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]365 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
366 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
367
368 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
369 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
370 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]371
372 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
373 Specifying attributes of variables.<br>
374 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
375 <tt>deprecated</tt>, <tt>transparent_union</tt>,
376 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]377
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]378 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
379 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
380 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]381 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]382
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]383 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Type-Attributes.html#Type%20Attributes">Type Attributes</a>: Specifying attributes of types.<br>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]384 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]385 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]386
387 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
388 all target specific attributes.</li>
389
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]390 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
391 Other built-in functions.<br>
392 We support all builtins which have a C language equivalent (e.g.,
393 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
394 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Chris Lattnerceebeb62004-06-18 06:26:29 +0000[diff] [blame]395 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt>
396 (currently ignored). We also support builtins for ISO C99 floating
Chris Lattnerd03b3bc2005-03-11 06:16:26 +0000[diff] [blame]397 point comparison macros (e.g., <tt>__builtin_islessequal</tt>), and
398 <tt>__builtin_prefetch</tt>.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]399 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]400
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]401 <p>The following extensions <b>are</b> known to be supported:</p>
402
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]403 <ol>
Chris Lattner7fe97dd2004-03-16 08:54:07 +0000[diff] [blame]404 <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 Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]405 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
406 <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 Lattnerca26c3e2004-06-22 03:48:17 +0000[diff] [blame]407 <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 Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]408 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
409 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
410 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
411 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
412 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
413 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
414 <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>
415 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
416 <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 Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]417 <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 Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]418 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Initializers.html#Initializers">Initializers</a>: Non-constant initializers.</li>
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]419 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
420or arrays as values.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]421 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Designated-Inits.html#Designated%20Inits">Designated Inits</a>: Labeling elements of initializers.</li>
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]422 <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 Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]423 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
424 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
425 <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 Lattner78537e42004-12-08 18:29:38 +0000[diff] [blame]426 <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 Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]427 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
428 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Character-Escapes.html#Character%20Escapes">Character Escapes</a>: <code>\e</code> stands for the character &lt;ESC&gt;.</li>
429 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
430 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
431 <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>
432 <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>
433 <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 Lattner25795bc2004-02-14 04:08:29 +0000[diff] [blame]434 <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 Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]435 <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>
436 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Attribute-Syntax.html#Attribute%20Syntax">Attribute Syntax</a>: Formal syntax for attributes.</li>
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]437 </ol></li>
438
439</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]440
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]441<p>If you run into GCC extensions which have not been included in any of these
442lists, please let us know (also including whether or not they work).</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]443
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]444</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]445
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]446<!-- ======================================================================= -->
447<div class="doc_subsection">
448 <a name="c++-fe">Known problems with the C++ front-end</a>
449</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]450
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]451<div class="doc_text">
452
Reid Spencere09ca642004-12-07 08:39:08 +0000[diff] [blame]453<p>For this release, the C++ front-end is considered to be fully
Chris Lattner7506b1d2004-12-07 08:04:13 +0000[diff] [blame]454tested and works for a number of non-trivial programs, including LLVM
455itself.</p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]456
457</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]458
459<!-- _______________________________________________________________________ -->
Chris Lattner3a51be12004-02-14 04:12:41 +0000[diff] [blame]460<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]461
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]462<div class="doc_text">
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]463
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]464<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]465<li>The C++ front-end inherits all problems afflicting the <a href="#c-fe">C
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]466 front-end</a>.</li>
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]467
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]468<li><b>IA-64 specific</b>: The C++ front-end does not use <a
469href="http://llvm.cs.uiuc.edu/PR406">IA64 ABI compliant layout of v-tables</a>.
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]470In particular, it just stores function pointers instead of function
471descriptors in the vtable. This bug prevents mixing C++ code compiled with
Chris Lattner04db8082004-08-02 20:29:51 +0000[diff] [blame]472LLVM with C++ objects compiled by other C++ compilers.</li>
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]473
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]474</ul>
475
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]476</div>
477
478<!-- _______________________________________________________________________ -->
479<div class="doc_subsubsection">
480 Notes
481</div>
482
483<div class="doc_text">
484
485<ul>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]486
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]487<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
488parser is significantly more standards compliant (and picky) than prior GCC
489versions. For more information, see the C++ section of the <a
Chris Lattner9e848092003-12-12 04:25:33 +0000[diff] [blame]490href="http://gcc.gnu.org/gcc-3.4/changes.html">GCC 3.4 release notes</a>.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]491
492<li>Destructors for local objects are not always run when a <tt>longjmp</tt> is
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]493 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]494 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]495 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]496 better than most compilers).</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]497
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]498<li>The LLVM C++ front-end follows the <a
499 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
500 This document, which is not Itanium specific, specifies a standard for name
501 mangling, class layout, v-table layout, RTTI formats, and other C++
502 representation issues. Because we use this API, code generated by the LLVM
503 compilers should be binary compatible with machine code generated by other
504 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
505 <i>However</i>, the exception handling mechanism used by LLVM is very
506 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]507 interact correctly</b>. </li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]508
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]509</ul>
Chris Lattnerfcc54b32003-10-07 22:14:37 +0000[diff] [blame]510
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]511</div>
512
513<!-- ======================================================================= -->
514<div class="doc_subsection">
515 <a name="x86-be">Known problems with the X86 back-end</a>
516</div>
517
518<div class="doc_text">
519
520<ul>
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]521 <li>none yet</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]522</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]523
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]524</div>
525
526<!-- ======================================================================= -->
527<div class="doc_subsection">
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]528 <a name="sparcv9-be">Known problems with the SparcV9 back-end</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]529</div>
530
531<div class="doc_text">
532
533<ul>
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]534<li><a href="http://llvm.cs.uiuc.edu/PR60">[sparcv9] SparcV9 backend miscompiles
535several programs in the LLVM test suite</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]536</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]537
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]538</div>
539
540<!-- ======================================================================= -->
541<div class="doc_subsection">
Chris Lattnerf32a5f52004-11-07 01:55:32 +0000[diff] [blame]542 <a name="ppc-be">Known problems with the PowerPC back-end</a>
543</div>
544
545<div class="doc_text">
546
547<ul>
548<li>none yet</li>
549</ul>
550
551</div>
552
553<!-- ======================================================================= -->
554<div class="doc_subsection">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]555 <a name="c-be">Known problems with the C back-end</a>
556</div>
557
558<div class="doc_text">
559
560<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]561
562<li>The C back-end produces code that violates the ANSI C Type-Based Alias
563Analysis rules. As such, special options may be necessary to compile the code
564(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]565problem probably cannot be fixed.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]566
Chris Lattner2855ecd2003-11-04 20:06:53 +0000[diff] [blame]567<li><a href="http://llvm.cs.uiuc.edu/PR56">Zero arg vararg functions are not
Chris Lattner2af46052003-10-24 04:03:19 +0000[diff] [blame]568supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]569frontends.</li>
Chris Lattner2af46052003-10-24 04:03:19 +0000[diff] [blame]570
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]571</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]572
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]573</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]574
Andrew Lenharth30a1f8f2005-05-03 16:59:09 +0000[diff] [blame]575<!-- ======================================================================= -->
576<div class="doc_subsection">
577 <a name="alpha-be">Known problems with the Alpha back-end</a>
578</div>
579
580<div class="doc_text">
581
582<ul>
583
584<li>On 21164s, some rare FP arithmatic sequences which may trap do not have the appropriate nops inserted to ensure restartability.</li>
585
586<li>Vararg functions are not supported.</li>
587
588</ul>
589
590</div>
591
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]592<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]593<div class="doc_section">
594 <a name="additionalinfo">Additional Information</a>
595</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]596<!-- *********************************************************************** -->
597
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]598<div class="doc_text">
599
600<p>A wide variety of additional information is available on the LLVM web page,
Misha Brukman109d9e82005-03-30 19:14:24 +0000[diff] [blame]601including <a href="http://llvm.cs.uiuc.edu/docs/#maillist">mailing lists</a> and
602<a href="http://llvm.cs.uiuc.edu/pubs/">publications describing algorithms and
603components implemented in LLVM</a>. The web page also contains versions of the
604API documentation which is up-to-date with the CVS version of the source code.
605You can access versions of these documents specific to this release by going
606into the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]607
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]608<p>If you have any questions or comments about LLVM, please feel free to contact
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]609us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing
610lists</a>.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]611
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]612</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]613
614<!-- *********************************************************************** -->
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]615
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]616<hr>
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]617<address>
Misha Brukman38847d52003-12-21 22:53:21 +0000[diff] [blame]618 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]619 src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
620 <a href="http://validator.w3.org/check/referer"><img
621 src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a>
622
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]623 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]624 Last modified: $Date$
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]625</address>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]626
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]627</body>
628</html>