Gitiles
Code Review Sign In
gerrit-public.fairphone.software / fp2-dev / platform / external / llvm / bb9fd30e6b578b90b4286034ad612564c9c48e48 / . / docs / ReleaseNotes.html
blob: c5570690f77792c3378af7c386c5c9d66659a98b [file] [log] [blame]
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">
Reid Spencerbb9fd302006-11-01 16:15:04 +0000[diff] [blame^]7 <title>LLVM 1.9 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
Reid Spencerbb9fd302006-11-01 16:15:04 +0000[diff] [blame^]11<div class="doc_title">LLVM 1.9 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 Lattnerc463b272005-10-29 07:07:09 +0000[diff] [blame]23 <p>Written by the <a href="http://llvm.org">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
Reid Spencerbb9fd302006-11-01 16:15:04 +0000[diff] [blame^]35infrastructure, release 1.9. Here we describe the status of LLVM, including any
Chris Lattner8a458762005-05-15 05:44:51 +0000[diff] [blame]36known problems and major improvements from the previous release. The most
Chris Lattnerd9ea0172006-08-08 17:27:28 +0000[diff] [blame]37up-to-date version of this document (corresponding to LLVM CVS) can be found
38on the <a
Chris Lattnerc30c5c72005-11-08 21:29:17 +0000[diff] [blame]39href="http://llvm.org/releases/">LLVM releases web site</a>. If you are
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]40not reading this on the LLVM web pages, you should probably go there because
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]41this document may be updated after the release.</p>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]42
Chris Lattner7506b1d2004-12-07 08:04:13 +0000[diff] [blame]43<p>For more information about LLVM, including information about the latest
Chris Lattnerc463b272005-10-29 07:07:09 +0000[diff] [blame]44release, please check out the <a href="http://llvm.org/">main LLVM
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]45web site</a>. If you have questions or comments, the <a
46href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM developer's mailing
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]47list</a> is a good place to send them.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]48
Chris Lattner78bf32b2004-12-09 22:22:58 +0000[diff] [blame]49<p>Note that if you are reading this file from CVS or the main LLVM web page,
50this document applies to the <i>next</i> release, not the current one. To see
51the release notes for the current or previous releases, see the <a
Chris Lattnerc463b272005-10-29 07:07:09 +0000[diff] [blame]52href="http://llvm.org/releases/">releases page</a>.</p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]53
54</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]55
56<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]57<div class="doc_section">
58 <a name="whatsnew">What's New?</a>
59</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]60<!-- *********************************************************************** -->
61
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]62<div class="doc_text">
63
Reid Spencerbb9fd302006-11-01 16:15:04 +0000[diff] [blame^]64<p>This is the tenth public release of the LLVM Compiler Infrastructure. This
65release incorporates a large number of enhancements and new features.
Chris Lattner44c933e2006-04-18 06:18:36 +0000[diff] [blame]66</p>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]67
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]68</div>
69
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]70<!--=========================================================================-->
Chris Lattner8a458762005-05-15 05:44:51 +0000[diff] [blame]71<div class="doc_subsection">
Reid Spencerbb9fd302006-11-01 16:15:04 +0000[diff] [blame^]72<a name="newfeatures">New Features in LLVM 1.9</a>
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]73</div>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]74
Chris Lattner44c933e2006-04-18 06:18:36 +0000[diff] [blame]75<!--_________________________________________________________________________-->
Reid Spencerbb9fd302006-11-01 16:15:04 +0000[diff] [blame^]76<div class="doc_subsubsection"><a name="elfdwarf">DWARF debugging
77support for X86/ELF</a></div>
Chris Lattner44c933e2006-04-18 06:18:36 +0000[diff] [blame]78<div class="doc_text">
Reid Spencerbb9fd302006-11-01 16:15:04 +0000[diff] [blame^]79<p>The llvm-gcc4 C front-end now generates debugging info for C and C++ for
80X86/ELF platforms (Linux). This extends the PPC/Darwin and X86/Darwin debugging
81support available in release 18.8 DWARF is a standard debugging format used on
82many platforms.</p>
Chris Lattner44c933e2006-04-18 06:18:36 +0000[diff] [blame]83</div>
84
85<!--_________________________________________________________________________-->
Reid Spencerbb9fd302006-11-01 16:15:04 +0000[diff] [blame^]86<div class="doc_subsubsection"><a name="signedinst">Signed Instructions</a></div>
Chris Lattner44c933e2006-04-18 06:18:36 +0000[diff] [blame]87<div class="doc_text">
Reid Spencerbb9fd302006-11-01 16:15:04 +0000[diff] [blame^]88<p>As a step towards making LLVM's integer types signless, several new
89instructions have been added to LLVM. The DIV instruction has become UDIV, SDIV,
90and FDIV. The REM instruction has become UREM, SREM and FREM. The SHR
91instruction has become ASHR and LSHR. See the <a href="LangRef.html">Language
92 Reference</a> for details on these new instructions.</p>
Chris Lattner44c933e2006-04-18 06:18:36 +0000[diff] [blame]93</div>
94
95<!--_________________________________________________________________________-->
Reid Spencerbb9fd302006-11-01 16:15:04 +0000[diff] [blame^]96<div class="doc_subsubsection"><a name="featureA">New Feature C</a></div>
Chris Lattner44c933e2006-04-18 06:18:36 +0000[diff] [blame]97<div class="doc_text">
Reid Spencerbb9fd302006-11-01 16:15:04 +0000[diff] [blame^]98<p>Describe feature C here.</p>
Chris Lattner44c933e2006-04-18 06:18:36 +0000[diff] [blame]99</div>
100
Chris Lattner738bd302006-04-18 06:32:08 +0000[diff] [blame]101<!--_________________________________________________________________________-->
Reid Spencerbb9fd302006-11-01 16:15:04 +0000[diff] [blame^]102<div class="doc_subsubsection"><a name="featureB">New Feature D</a></div>
Chris Lattner738bd302006-04-18 06:32:08 +0000[diff] [blame]103<div class="doc_text">
Reid Spencerbb9fd302006-11-01 16:15:04 +0000[diff] [blame^]104<p>Describe feature D here.</p>
Chris Lattner738bd302006-04-18 06:32:08 +0000[diff] [blame]105</div>
106
Chris Lattner1c1a85c2006-04-19 04:02:47 +0000[diff] [blame]107<!--_________________________________________________________________________-->
Reid Spencerbb9fd302006-11-01 16:15:04 +0000[diff] [blame^]108<div class="doc_subsubsection"><a name="jitrelease">New Feature E</a></div>
Chris Lattner1c1a85c2006-04-19 04:02:47 +0000[diff] [blame]109<div class="doc_text">
Reid Spencerbb9fd302006-11-01 16:15:04 +0000[diff] [blame^]110<p>Describe feature E here.</p>
Chris Lattner1c1a85c2006-04-19 04:02:47 +0000[diff] [blame]111</div>
Chris Lattner44c933e2006-04-18 06:18:36 +0000[diff] [blame]112
113<!--_________________________________________________________________________-->
Chris Lattnerd9ea0172006-08-08 17:27:28 +0000[diff] [blame]114<div class="doc_subsubsection"><a name="other">Other Improvements</a></div>
Chris Lattner58504a62006-02-05 06:39:36 +0000[diff] [blame]115<div class="doc_text">
Chris Lattnerd9ea0172006-08-08 17:27:28 +0000[diff] [blame]116<p>This release includes many other improvements, including improvements to
117 the optimizers and code generators (improving the generated code) changes to
118 speed up the compiler in many ways (improving algorithms and fine tuning
119 code), and changes to reduce the code size of the compiler itself.</p>
120
121<p>More specific changes include:</p>
122
Chris Lattner58504a62006-02-05 06:39:36 +0000[diff] [blame]123<ul>
Chris Lattnerd9ea0172006-08-08 17:27:28 +0000[diff] [blame]124<li>LLVM 1.8 includes an initial ARM backend. This backend is in early
125 development stages.</li>
126<li>LLVM 1.8 now includes significantly better support for mingw and
127 cygwin.</li>
128<li>The <a href="CommandGuide/html/llvm-config.html">llvm-config</a> tool is
129 now built by default and has several new features.</li>
130<li>The X86 and PPC backends now use the correct platform ABI for passing
131 vectors as arguments to functions.</li>
132<li>The X86 backend now includes support for the Microsoft ML assembler
133 ("MASM").</li>
134<li>The PowerPC backend now pattern matches the 'rlwimi' instruction more
135 aggressively.</li>
136<li>Most of LLVM is now built with "-pedantic", ensuring better portability
137 to more C++ Compilers.</li>
138<li>The PowerPC backend now includes initial 64-bit support. The JIT is not
139 complete, and the static compiler has a couple of known bugs, but support
140 is mostly in place. LLVM 1.9 will include completed PPC-64 support. </li>
Chris Lattner738bd302006-04-18 06:32:08 +0000[diff] [blame]141
Chris Lattner58504a62006-02-05 06:39:36 +0000[diff] [blame]142</ul>
143</div>
John Criswelle531ec52005-06-29 16:22:34 +0000[diff] [blame]144
Chris Lattnerc5d658a2006-03-03 00:34:26 +0000[diff] [blame]145<!--=========================================================================-->
146<div class="doc_subsection">
Chris Lattnerd9ea0172006-08-08 17:27:28 +0000[diff] [blame]147<a name="changes">Significant Changes in LLVM 1.8</a>
Chris Lattnerc5d658a2006-03-03 00:34:26 +0000[diff] [blame]148</div>
149
150<div class="doc_text">
151<ul>
Chris Lattnerd9ea0172006-08-08 17:27:28 +0000[diff] [blame]152<li>The LLVM "SparcV9" backend (deprecated in LLVM 1.7) has been removed in
153LLVM 1.8. The LLVM "Sparc" backend replaces it.</li>
154<li>The --version option now prints more useful information, including the
155 build configuration for the tool.</li>
Chris Lattnerc5d658a2006-03-03 00:34:26 +0000[diff] [blame]156</ul>
157</div>
158
159
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]160<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]161<div class="doc_section">
162 <a name="portability">Portability and Supported Platforms</a>
163</div>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]164<!-- *********************************************************************** -->
165
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]166<div class="doc_text">
167
John Criswell0b5b5e92004-12-08 20:35:47 +0000[diff] [blame]168<p>LLVM is known to work on the following platforms:</p>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]169
170<ul>
Reid Spencer00812e22005-05-17 02:47:27 +0000[diff] [blame]171 <li>Intel and AMD machines running Red Hat Linux, Fedora Core and FreeBSD
172 (and probably other unix-like systems).</li>
Chris Lattner7ea41e32006-08-09 04:10:32 +0000[diff] [blame]173<li>Intel and AMD machines running on Win32 using MinGW libraries (native)</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]174<li>Sun UltraSPARC workstations running Solaris 8.</li>
Chris Lattner7506b1d2004-12-07 08:04:13 +0000[diff] [blame]175<li>Intel and AMD machines running on Win32 with the Cygwin libraries (limited
176 support is available for native builds with Visual C++).</li>
Chris Lattnerfeaf9602005-10-29 05:14:01 +0000[diff] [blame]177<li>PowerPC and X86-based Mac OS X systems, running 10.2 and above.</li>
John Criswell9321fa82005-05-13 20:28:15 +0000[diff] [blame]178<li>Alpha-based machines running Debian GNU/Linux.</li>
179<li>Itanium-based machines running Linux and HP-UX.</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]180</ul>
181
Brian Gaekeb0fd7612004-05-09 05:28:35 +0000[diff] [blame]182<p>The core LLVM infrastructure uses
183<a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself
184to the machine and operating system on which it is built. However, minor
185porting may be required to get LLVM to work on new platforms. We welcome your
186portability patches and reports of successful builds or error messages.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]187
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]188</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]189
190<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]191<div class="doc_section">
192 <a name="knownproblems">Known Problems</a>
193</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]194<!-- *********************************************************************** -->
195
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]196<div class="doc_text">
197
198<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]199component. As new problems are discovered, they will be added to these
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]200sections. If you run into a problem, please check the <a
Chris Lattnerc463b272005-10-29 07:07:09 +0000[diff] [blame]201href="http://llvm.org/bugs/">LLVM bug database</a> and submit a bug if
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]202there isn't already one.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]203
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]204</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]205
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]206<!-- ======================================================================= -->
207<div class="doc_subsection">
208 <a name="experimental">Experimental features included with this release</a>
209</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]210
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]211<div class="doc_text">
212
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]213<p>The following components of this LLVM release are either untested, known to
214be broken or unreliable, or are in early development. These components should
215not be relied on, and bugs should not be filed against them, but they may be
216useful to some people. In particular, if you would like to work on one of these
Chris Lattner49e693e2006-08-09 04:08:52 +0000[diff] [blame]217components, please contact us on the <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev list</a>.</p>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]218
219<ul>
Chris Lattner44c933e2006-04-18 06:18:36 +0000[diff] [blame]220<li>The <tt>-cee</tt> pass is known to be buggy, and may be removed in in a
221 future release.</li>
Chris Lattner58504a62006-02-05 06:39:36 +0000[diff] [blame]222<li>The IA64 code generator is experimental.</li>
Chris Lattnerc463b272005-10-29 07:07:09 +0000[diff] [blame]223<li>The Alpha JIT is experimental.</li>
Chris Lattner44c933e2006-04-18 06:18:36 +0000[diff] [blame]224<li>"<tt>-filetype=asm</tt>" (the default) is the only supported value for the
225 <tt>-filetype</tt> llc option.</li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]226</ul>
227
228</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]229
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]230<!-- ======================================================================= -->
231<div class="doc_subsection">
John Criswellc0c186d2005-11-08 21:11:33 +0000[diff] [blame]232 <a name="build">Known problems with the Build System</a>
233</div>
234
235<div class="doc_text">
236
237<ul>
Chris Lattner8bb0a6c2006-04-20 04:24:28 +0000[diff] [blame]238<li>none yet</li>
John Criswellc0c186d2005-11-08 21:11:33 +0000[diff] [blame]239</ul>
240</div>
241
242
243<!-- ======================================================================= -->
244<div class="doc_subsection">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]245 <a name="core">Known problems with the LLVM Core</a>
246</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]247
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]248<div class="doc_text">
249
250<ul>
Misha Brukman109d9e82005-03-30 19:14:24 +0000[diff] [blame]251 <li>In the JIT, <tt>dlsym()</tt> on a symbol compiled by the JIT will not
252 work.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]253</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]254</div>
255
256<!-- ======================================================================= -->
257<div class="doc_subsection">
258 <a name="c-fe">Known problems with the C front-end</a>
259</div>
Chris Lattner47588f92003-10-02 05:07:23 +0000[diff] [blame]260
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]261<!-- _______________________________________________________________________ -->
Chris Lattnerb40efb32003-12-14 05:03:43 +0000[diff] [blame]262<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]263
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]264<div class="doc_text">
Chris Lattnerc5d658a2006-03-03 00:34:26 +0000[diff] [blame]265
Chris Lattner44c933e2006-04-18 06:18:36 +0000[diff] [blame]266<p>
Chris Lattnerd9ea0172006-08-08 17:27:28 +0000[diff] [blame]267llvm-gcc3 has many significant problems that are fixed by llvm-gcc4.
Chris Lattnercf797e92006-04-19 04:12:01 +0000[diff] [blame]268Two major ones include:</p>
Chris Lattnerc5d658a2006-03-03 00:34:26 +0000[diff] [blame]269
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]270<ul>
Chris Lattner44c933e2006-04-18 06:18:36 +0000[diff] [blame]271<li>With llvm-gcc3,
272 C99 variable sized arrays do not release stack memory when they go out of
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]273 scope. Thus, the following program may run out of stack space:
274<pre>
275 for (i = 0; i != 1000000; ++i) {
276 int X[n];
277 foo(X);
278 }
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]279</pre></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]280
Chris Lattner44c933e2006-04-18 06:18:36 +0000[diff] [blame]281<li>With llvm-gcc3, Initialization of global union variables can only be done <a
Chris Lattnerc463b272005-10-29 07:07:09 +0000[diff] [blame]282href="http://llvm.org/PR162">with the largest union member</a>.</li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]283
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]284</ul>
Chris Lattnerd9ea0172006-08-08 17:27:28 +0000[diff] [blame]285
286<p>llvm-gcc4 is far more stable and produces better code than llvm-gcc3, but
287does not currently support Link-Time-Optimization or C++ Exception Handling,
288which llvm-gcc3 does.</p>
289
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]290</div>
291
292<!-- _______________________________________________________________________ -->
293<div class="doc_subsubsection">
294 Notes
295</div>
296
297<div class="doc_text">
298
299<ul>
300
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]301<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]302support for floating point data types of any size other than 32 and 64
303bits.</li>
304
305<li>The following Unix system functionality has not been tested and may not
306work:
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]307 <ol>
308 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
309 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
310 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
311 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
312 - These functions have not been tested.
313 </ol></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]314
315<li>Although many GCC extensions are supported, some are not. In particular,
316 the following extensions are known to <b>not be</b> supported:
317 <ol>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]318 <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]319 <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>
320 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
321 <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]322 <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]323 <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>
324 <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]325 <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>
326 <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]327 <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]328 <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]329 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]330
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]331 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]332 attribute means that the LLVM compiler ignores the presence of the attribute,
333 but the code should still work. An unsupported attribute is one which is
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]334 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]335 the program.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]336
337 <ol>
338 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
339 Arrays whose length is computed at run time.<br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]340 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]341
342 <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]343
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]344 Declaring that functions have no side effects or that they can never
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]345 return.<br>
346
347 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
John Criswell0b5b5e92004-12-08 20:35:47 +0000[diff] [blame]348 <tt>noreturn</tt>, <tt>constructor</tt>, <tt>destructor</tt>,
Chris Lattneraef8c642005-12-05 05:23:06 +0000[diff] [blame]349 <tt>unused</tt>, <tt>used</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]350 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
351
John Criswell0b5b5e92004-12-08 20:35:47 +0000[diff] [blame]352 <b>Ignored:</b> <tt>noinline</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]353 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
354 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
355
Chris Lattneraef8c642005-12-05 05:23:06 +0000[diff] [blame]356 <b>Unsupported:</b> <tt>section</tt>, <tt>alias</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]357 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
358 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]359
360 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
361 Specifying attributes of variables.<br>
362 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
363 <tt>deprecated</tt>, <tt>transparent_union</tt>,
Chris Lattneraef8c642005-12-05 05:23:06 +0000[diff] [blame]364 <tt>unused</tt>, <tt>used</tt>, <tt>weak</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]365
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]366 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
367 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
368 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]369 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]370
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]371 <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]372 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]373 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]374
375 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
376 all target specific attributes.</li>
377
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]378 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
379 Other built-in functions.<br>
380 We support all builtins which have a C language equivalent (e.g.,
381 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
382 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Chris Lattnerceebeb62004-06-18 06:26:29 +0000[diff] [blame]383 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt>
384 (currently ignored). We also support builtins for ISO C99 floating
Chris Lattner7939b782005-05-07 02:21:21 +0000[diff] [blame]385 point comparison macros (e.g., <tt>__builtin_islessequal</tt>),
386 <tt>__builtin_prefetch</tt>, <tt>__builtin_popcount[ll]</tt>,
387 <tt>__builtin_clz[ll]</tt>, and <tt>__builtin_ctz[ll]</tt>.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]388 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]389
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]390 <p>The following extensions <b>are</b> known to be supported:</p>
391
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]392 <ol>
Chris Lattner7fe97dd2004-03-16 08:54:07 +0000[diff] [blame]393 <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]394 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
395 <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]396 <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]397 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
398 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
399 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
400 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
401 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
402 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
403 <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>
404 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
405 <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]406 <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]407 <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]408 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
409or arrays as values.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]410 <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]411 <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]412 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
413 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
414 <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]415 <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]416 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
417 <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>
418 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
419 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
420 <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>
421 <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>
422 <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]423 <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]424 <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>
425 <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]426 </ol></li>
427
428</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]429
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]430<p>If you run into GCC extensions which have not been included in any of these
431lists, please let us know (also including whether or not they work).</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]432
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]433</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]434
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]435<!-- ======================================================================= -->
436<div class="doc_subsection">
437 <a name="c++-fe">Known problems with the C++ front-end</a>
438</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]439
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]440<div class="doc_text">
441
Reid Spencere09ca642004-12-07 08:39:08 +0000[diff] [blame]442<p>For this release, the C++ front-end is considered to be fully
Chris Lattner7506b1d2004-12-07 08:04:13 +0000[diff] [blame]443tested and works for a number of non-trivial programs, including LLVM
444itself.</p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]445
446</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]447
448<!-- _______________________________________________________________________ -->
Chris Lattner3a51be12004-02-14 04:12:41 +0000[diff] [blame]449<div class="doc_subsubsection">Bugs</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">
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]452
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]453<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]454<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]455 front-end</a>.</li>
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]456
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]457</ul>
458
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]459</div>
460
461<!-- _______________________________________________________________________ -->
462<div class="doc_subsubsection">
463 Notes
464</div>
465
466<div class="doc_text">
467
468<ul>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]469
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]470<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]471 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]472 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]473 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]474 better than most compilers).</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]475
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]476<li>The LLVM C++ front-end follows the <a
477 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
478 This document, which is not Itanium specific, specifies a standard for name
479 mangling, class layout, v-table layout, RTTI formats, and other C++
480 representation issues. Because we use this API, code generated by the LLVM
481 compilers should be binary compatible with machine code generated by other
482 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
483 <i>However</i>, the exception handling mechanism used by LLVM is very
484 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]485 interact correctly</b>. </li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]486
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]487</ul>
Chris Lattnerfcc54b32003-10-07 22:14:37 +0000[diff] [blame]488
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]489</div>
490
491<!-- ======================================================================= -->
492<div class="doc_subsection">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]493 <a name="c-be">Known problems with the C back-end</a>
494</div>
495
496<div class="doc_text">
497
498<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]499
500<li>The C back-end produces code that violates the ANSI C Type-Based Alias
501Analysis rules. As such, special options may be necessary to compile the code
502(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]503problem probably cannot be fixed.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]504
Chris Lattnerc463b272005-10-29 07:07:09 +0000[diff] [blame]505<li><a href="http://llvm.org/PR56">Zero arg vararg functions are not
Chris Lattner2af46052003-10-24 04:03:19 +0000[diff] [blame]506supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]507frontends.</li>
Chris Lattner2af46052003-10-24 04:03:19 +0000[diff] [blame]508
Chris Lattner44c933e2006-04-18 06:18:36 +0000[diff] [blame]509<li>The C backend does not correctly implement the <a
510href="LangRef.html#i_stacksave"><tt>llvm.stacksave</tt></a> or
511<a href="LangRef.html#i_stackrestore"><tt>llvm.stackrestore</tt></a>
512intrinsics. This means that some code compiled by it can run out of stack
513space if they depend on these (e.g. C99 varargs).</li>
514
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]515</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]516
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]517</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]518
Andrew Lenharth30a1f8f2005-05-03 16:59:09 +0000[diff] [blame]519<!-- ======================================================================= -->
520<div class="doc_subsection">
Chris Lattnerf9b1f462005-05-16 17:06:29 +0000[diff] [blame]521 <a name="x86-be">Known problems with the X86 back-end</a>
522</div>
523
524<div class="doc_text">
525
526<ul>
Chris Lattnerd9ea0172006-08-08 17:27:28 +0000[diff] [blame]527<li>none yet.</li>
Chris Lattnerf9b1f462005-05-16 17:06:29 +0000[diff] [blame]528</ul>
529
530</div>
531
532<!-- ======================================================================= -->
533<div class="doc_subsection">
534 <a name="ppc-be">Known problems with the PowerPC back-end</a>
535</div>
536
537<div class="doc_text">
538
539<ul>
Chris Lattner44c933e2006-04-18 06:18:36 +0000[diff] [blame]540<li><a href="http://llvm.org/PR642">PowerPC backend does not correctly
541implement ordered FP comparisons</a>.</li>
Chris Lattnerf9b1f462005-05-16 17:06:29 +0000[diff] [blame]542</ul>
543
544</div>
545
546<!-- ======================================================================= -->
547<div class="doc_subsection">
Andrew Lenharth30a1f8f2005-05-03 16:59:09 +0000[diff] [blame]548 <a name="alpha-be">Known problems with the Alpha back-end</a>
549</div>
550
551<div class="doc_text">
552
553<ul>
554
Chris Lattnerf9b1f462005-05-16 17:06:29 +0000[diff] [blame]555<li>On 21164s, some rare FP arithmetic sequences which may trap do not have the
556appropriate nops inserted to ensure restartability.</li>
Andrew Lenharth30a1f8f2005-05-03 16:59:09 +0000[diff] [blame]557
Andrew Lenharth30a1f8f2005-05-03 16:59:09 +0000[diff] [blame]558</ul>
559
560</div>
561
Duraid Madina2e36d6e2005-05-14 05:48:13 +0000[diff] [blame]562<!-- ======================================================================= -->
563<div class="doc_subsection">
564 <a name="ia64-be">Known problems with the IA64 back-end</a>
565</div>
566
567<div class="doc_text">
568
569<ul>
570
571<li>C++ programs are likely to fail on IA64, as calls to <tt>setjmp</tt> are
572made where the argument is not 16-byte aligned, as required on IA64. (Strictly
573speaking this is not a bug in the IA64 back-end; it will also be encountered
574when building C++ programs using the C back-end.)</li>
575
Chris Lattnerc463b272005-10-29 07:07:09 +0000[diff] [blame]576<li>The C++ front-end does not use <a href="http://llvm.org/PR406">IA64
Chris Lattnerf9b1f462005-05-16 17:06:29 +0000[diff] [blame]577ABI compliant layout of v-tables</a>. In particular, it just stores function
578pointers instead of function descriptors in the vtable. This bug prevents
579mixing C++ code compiled with LLVM with C++ objects compiled by other C++
580compilers.</li>
Duraid Madina2e36d6e2005-05-14 05:48:13 +0000[diff] [blame]581
Chris Lattnerf9b1f462005-05-16 17:06:29 +0000[diff] [blame]582<li>There are a few ABI violations which will lead to problems when mixing LLVM
583output with code built with other compilers, particularly for floating-point
584programs.</li>
585
586<li>Defining vararg functions is not supported (but calling them is ok).</li>
Duraid Madina2e36d6e2005-05-14 05:48:13 +0000[diff] [blame]587
588</ul>
589
590</div>
591
Chris Lattner98a493c2005-05-15 16:01:20 +0000[diff] [blame]592<!-- ======================================================================= -->
593<div class="doc_subsection">
Chris Lattner44c933e2006-04-18 06:18:36 +0000[diff] [blame]594 <a name="sparc-be">Known problems with the SPARC back-end</a>
Chris Lattner98a493c2005-05-15 16:01:20 +0000[diff] [blame]595</div>
596
597<div class="doc_text">
598
599<ul>
Chris Lattnerc71173a2006-04-19 04:05:21 +0000[diff] [blame]600<li>The SPARC backend only supports the 32-bit SPARC ABI (-m32), it does not
601 support the 64-bit SPARC ABI (-m64).</li>
Chris Lattner98a493c2005-05-15 16:01:20 +0000[diff] [blame]602</ul>
Chris Lattner44c933e2006-04-18 06:18:36 +0000[diff] [blame]603
604</div>
605
Chris Lattner44c933e2006-04-18 06:18:36 +0000[diff] [blame]606<!-- ======================================================================= -->
607<div class="doc_subsection">
Chris Lattnerd9ea0172006-08-08 17:27:28 +0000[diff] [blame]608 <a name="arm-be">Known problems with the ARM back-end</a>
Chris Lattner44c933e2006-04-18 06:18:36 +0000[diff] [blame]609</div>
610
611<div class="doc_text">
612
613<ul>
Chris Lattnerd9ea0172006-08-08 17:27:28 +0000[diff] [blame]614<li>The ARM backend is currently in early development stages, it is not
615ready for production use.</li>
Chris Lattner44c933e2006-04-18 06:18:36 +0000[diff] [blame]616</ul>
617
Chris Lattner98a493c2005-05-15 16:01:20 +0000[diff] [blame]618</div>
619
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]620<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]621<div class="doc_section">
622 <a name="additionalinfo">Additional Information</a>
623</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]624<!-- *********************************************************************** -->
625
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]626<div class="doc_text">
627
Chris Lattner416db102005-05-16 17:13:10 +0000[diff] [blame]628<p>A wide variety of additional information is available on the <a
Chris Lattnerc463b272005-10-29 07:07:09 +0000[diff] [blame]629href="http://llvm.org">LLVM web page</a>, including <a
630href="http://llvm.org/docs/">documentation</a> and <a
631href="http://llvm.org/pubs/">publications describing algorithms and
Misha Brukman109d9e82005-03-30 19:14:24 +0000[diff] [blame]632components implemented in LLVM</a>. The web page also contains versions of the
633API documentation which is up-to-date with the CVS version of the source code.
634You can access versions of these documents specific to this release by going
635into the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]636
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]637<p>If you have any questions or comments about LLVM, please feel free to contact
Chris Lattnerc463b272005-10-29 07:07:09 +0000[diff] [blame]638us via the <a href="http://llvm.org/docs/#maillist"> mailing
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]639lists</a>.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]640
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]641</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]642
643<!-- *********************************************************************** -->
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]644
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]645<hr>
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]646<address>
Misha Brukman38847d52003-12-21 22:53:21 +0000[diff] [blame]647 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]648 src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
649 <a href="http://validator.w3.org/check/referer"><img
650 src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a>
651
Chris Lattnerc463b272005-10-29 07:07:09 +0000[diff] [blame]652 <a href="http://llvm.org/">The LLVM Compiler Infrastructure</a><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]653 Last modified: $Date$
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]654</address>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]655
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]656</body>
657</html>