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gerrit-public.fairphone.software / toolchain / llvm-project / afa5f492e5fc602a042a8b69155570a906396a5e / . / llvm / docs / ReleaseNotes.html
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Chris Lattner7422bce2008-02-06 06:30:34 +0000[diff] [blame]7 <title>LLVM 2.2 Release Notes</title>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]8</head>
9<body>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]10
Chris Lattner7422bce2008-02-06 06:30:34 +0000[diff] [blame]11<div class="doc_title">LLVM 2.2 Release Notes</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]12
13<ol>
Misha Brukman80731b92003-11-22 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 Lattner77a51732004-04-30 22:17:12 +0000[diff] [blame]16 <li><a href="GettingStarted.html">Installation Instructions</a></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]17 <li><a href="#portability">Portability and Supported Platforms</a></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]18 <li><a href="#knownproblems">Known Problems</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]19 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]20</ol>
21
Chris Lattner020e1fc2004-05-23 21:07:27 +0000[diff] [blame]22<div class="doc_author">
Chris Lattnera69595e2005-10-29 07:07:09 +0000[diff] [blame]23 <p>Written by the <a href="http://llvm.org">LLVM Team</a><p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]24</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]25
26<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]27<div class="doc_section">
28 <a name="intro">Introduction</a>
29</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]30<!-- *********************************************************************** -->
31
Misha Brukman80731b92003-11-22 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 Lattner7422bce2008-02-06 06:30:34 +0000[diff] [blame]35infrastructure, release 2.2. Here we describe the status of LLVM, including
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]36major improvements from the previous release and any known problems. All LLVM
Chris Lattner98a33492007-05-09 04:58:11 +0000[diff] [blame]37releases may be downloaded from the <a href="http://llvm.org/releases/">LLVM
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]38releases web site</a>.</p>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]39
Chris Lattnerb5bb5972004-12-07 08:04:13 +0000[diff] [blame]40<p>For more information about LLVM, including information about the latest
Chris Lattnera69595e2005-10-29 07:07:09 +0000[diff] [blame]41release, please check out the <a href="http://llvm.org/">main LLVM
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]42web site</a>. If you have questions or comments, the <a
43href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM developer's mailing
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]44list</a> is a good place to send them.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]45
Reid Spencerc7f87f22007-07-09 08:04:31 +0000[diff] [blame]46<p>Note that if you are reading this file from a Subversion checkout or the
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]47main LLVM web page, this document applies to the <i>next</i> release, not the
48current one. To see the release notes for a specific releases, please see the
49<a href="http://llvm.org/releases/">releases page</a>.</p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]50
51</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]52
53<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]54<div class="doc_section">
55 <a name="whatsnew">What's New?</a>
56</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]57<!-- *********************************************************************** -->
58
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]59<div class="doc_text">
60
Chris Lattner7422bce2008-02-06 06:30:34 +0000[diff] [blame]61<p>This is the thirteenth public release of the LLVM Compiler Infrastructure.
62It includes many features and refinements from LLVM 2.1.</p>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]63
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]64</div>
65
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]66<!--=========================================================================-->
Chris Lattner406bddf2005-05-15 05:44:51 +0000[diff] [blame]67<div class="doc_subsection">
Chris Lattner7422bce2008-02-06 06:30:34 +0000[diff] [blame]68<a name="frontends">llvm-gcc 4.0, llvm-gcc 4.2, and clang</a>
Chris Lattner9f871732006-04-18 06:18:36 +0000[diff] [blame]69</div>
70
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]71<div class="doc_text">
Chris Lattner727c3742007-05-18 06:33:02 +0000[diff] [blame]72
Chris Lattner7422bce2008-02-06 06:30:34 +0000[diff] [blame]73<p>LLVM 2.2 fully supports both the llvm-gcc 4.0 and llvm-gcc 4.2 front-ends (in
74LLVM 2.1, llvm-gcc 4.2 was beta). Since LLVM 2.1, the llvm-gcc 4.2 front-end
75has made leaps and bounds and is now at least as good as 4.0 in virtually every
76area, and is better in several areas (for example, exception handling
77correctness). We strongly recommend that you migrate from llvm-gcc 4.0 to
78llvm-gcc 4.2 in this release cycle because <b>LLVM 2.2 is the last release
79that will support llvm-gcc 4.0</b>: LLVM 2.3 will only support the llvm-gcc
804.2 front-end.</p>
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]81
Chris Lattner7422bce2008-02-06 06:30:34 +0000[diff] [blame]82<p>The <a href="http://clang.llvm.org/">clang project</a> is an effort
83to build a set of new front-end technology for the LLVM optimizer and code
84generator. Currently, its C and Objective-C support is maturing nicely, and it
85has advanced source-to-source analysis and transformation capabilities. If you
86are interested in building source-level tools for C and Objective-C (and
87eventually C++), you should take a look. However, note that clang is not an
88official part of the LLVM 2.2 release. If you are interested in this project,
89please see the web site and check it out from SVN head.</p>
Chris Lattner727c3742007-05-18 06:33:02 +0000[diff] [blame]90
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]91</div>
92
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]93<!--=========================================================================-->
94<div class="doc_subsection">
95<a name="optimizer">Optimizer Improvements</a>
96</div>
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]97
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]98<div class="doc_text">
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]99
Chris Lattner4734a352007-09-26 05:44:21 +0000[diff] [blame]100<p>Some of the most noticable feature improvements this release have been in the
101optimizer, speeding it up and making it more aggressive. For example:</p>
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]102
103<ul>
Tanya Lattner6ee68ca2007-05-16 23:25:46 +0000[diff] [blame]104
Chris Lattner7422bce2008-02-06 06:30:34 +0000[diff] [blame]105<li>.</li>
Tanya Lattner6ee68ca2007-05-16 23:25:46 +0000[diff] [blame]106
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]107</ul>
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]108
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]109</div>
110
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]111<!--=========================================================================-->
112<div class="doc_subsection">
113<a name="codegen">Code Generator Improvements</a>
114</div>
115
116<div class="doc_text">
117
Chris Lattner4734a352007-09-26 05:44:21 +0000[diff] [blame]118<p>One of the main focuses of this release was performance tuning and bug
119 fixing. In addition to these, several new major changes occurred:</p>
120
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]121<ul>
122
Chris Lattner7422bce2008-02-06 06:30:34 +0000[diff] [blame]123<li>.</li>
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]124
125</ul>
126
127</div>
128
129
130<!--=========================================================================-->
131<div class="doc_subsection">
132<a name="targetspecific">Target Specific Improvements</a>
133</div>
Chris Lattner727c3742007-05-18 06:33:02 +0000[diff] [blame]134
Chris Lattner89e761c2006-04-18 06:32:08 +0000[diff] [blame]135<div class="doc_text">
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]136<p>New features include:
137</p>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]138
139<ul>
Chris Lattner7422bce2008-02-06 06:30:34 +0000[diff] [blame]140<li>.</li>
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]141</ul>
142
143</div>
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]144
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]145
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]146<!--=========================================================================-->
147<div class="doc_subsection">
148<a name="llvmgccimprovements">llvm-gcc Improvements</a>
149</div>
Tanya Lattner6ee68ca2007-05-16 23:25:46 +0000[diff] [blame]150
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]151<div class="doc_text">
152<p>New features include:
153</p>
Tanya Lattner6ee68ca2007-05-16 23:25:46 +0000[diff] [blame]154
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]155<ul>
Chris Lattner7422bce2008-02-06 06:30:34 +0000[diff] [blame]156<li>.</li>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]157</ul>
158
Chris Lattner89e761c2006-04-18 06:32:08 +0000[diff] [blame]159</div>
160
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]161
162<!--=========================================================================-->
163<div class="doc_subsection">
164<a name="coreimprovements">LLVM Core Improvements</a>
165</div>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]166
Chris Lattner0b7fd712006-04-19 04:02:47 +0000[diff] [blame]167<div class="doc_text">
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]168<p>New features include:
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]169</p>
170
171<ul>
Chris Lattner7422bce2008-02-06 06:30:34 +0000[diff] [blame]172<li>.</li>
Chris Lattner8ce1ba42007-05-17 21:41:31 +0000[diff] [blame]173</ul>
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]174
Chris Lattner8ce1ba42007-05-17 21:41:31 +0000[diff] [blame]175</div>
Chris Lattner72a269f2006-03-03 00:34:26 +0000[diff] [blame]176
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]177<!--=========================================================================-->
178<div class="doc_subsection">
179<a name="otherimprovements">Other Improvements</a>
180</div>
181
182<div class="doc_text">
183<p>New features include:
184</p>
185
186<ul>
Chris Lattner7422bce2008-02-06 06:30:34 +0000[diff] [blame]187<li>.</li>
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]188</ul>
189
190</div>
Chris Lattner72a269f2006-03-03 00:34:26 +0000[diff] [blame]191
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]192<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]193<div class="doc_section">
194 <a name="portability">Portability and Supported Platforms</a>
195</div>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]196<!-- *********************************************************************** -->
197
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]198<div class="doc_text">
199
John Criswell64307722004-12-08 20:35:47 +0000[diff] [blame]200<p>LLVM is known to work on the following platforms:</p>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]201
202<ul>
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]203<li>Intel and AMD machines running Red Hat Linux, Fedora Core and FreeBSD
Reid Spencer9803b402005-05-17 02:47:27 +0000[diff] [blame]204 (and probably other unix-like systems).</li>
Chris Lattner7422bce2008-02-06 06:30:34 +0000[diff] [blame]205<li>PowerPC and X86-based Mac OS X systems, running 10.3 and above in 32-bit and
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]206 64-bit modes.</li>
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]207<li>Intel and AMD machines running on Win32 using MinGW libraries (native)</li>
208<li>Intel and AMD machines running on Win32 with the Cygwin libraries (limited
209 support is available for native builds with Visual C++).</li>
210<li>Sun UltraSPARC workstations running Solaris 8.</li>
John Criswelld5234922005-05-13 20:28:15 +0000[diff] [blame]211<li>Alpha-based machines running Debian GNU/Linux.</li>
212<li>Itanium-based machines running Linux and HP-UX.</li>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]213</ul>
214
Brian Gaekee3e557e2004-05-09 05:28:35 +0000[diff] [blame]215<p>The core LLVM infrastructure uses
216<a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself
217to the machine and operating system on which it is built. However, minor
218porting may be required to get LLVM to work on new platforms. We welcome your
219portability patches and reports of successful builds or error messages.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]220
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]221</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]222
223<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]224<div class="doc_section">
225 <a name="knownproblems">Known Problems</a>
226</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]227<!-- *********************************************************************** -->
228
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]229<div class="doc_text">
230
231<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]232component. As new problems are discovered, they will be added to these
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]233sections. If you run into a problem, please check the <a
Chris Lattnera69595e2005-10-29 07:07:09 +0000[diff] [blame]234href="http://llvm.org/bugs/">LLVM bug database</a> and submit a bug if
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]235there isn't already one.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]236
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]237</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]238
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]239<!-- ======================================================================= -->
240<div class="doc_subsection">
241 <a name="experimental">Experimental features included with this release</a>
242</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]243
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]244<div class="doc_text">
245
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]246<p>The following components of this LLVM release are either untested, known to
247be broken or unreliable, or are in early development. These components should
248not be relied on, and bugs should not be filed against them, but they may be
249useful to some people. In particular, if you would like to work on one of these
Chris Lattner05a225b2006-08-09 04:08:52 +0000[diff] [blame]250components, please contact us on the <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev list</a>.</p>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]251
252<ul>
Bill Wendling982d57d2007-09-25 20:45:10 +0000[diff] [blame]253<li>The <tt>-cee</tt> pass is known to be buggy, and may be removed in a
Chris Lattner9f871732006-04-18 06:18:36 +0000[diff] [blame]254 future release.</li>
Chris Lattner7422bce2008-02-06 06:30:34 +0000[diff] [blame]255<li>The MSIL, IA64, Alpha, and MIPS backends are experimental.</li>
256<li>The LLC "<tt>-filetype=asm</tt>" (the default) is the only supported
257 value for this option.</li>
258<li>The llvmc tool is not supported.</li>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]259</ul>
260
261</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]262
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]263<!-- ======================================================================= -->
264<div class="doc_subsection">
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]265 <a name="x86-be">Known problems with the X86 back-end</a>
John Criswell3bdbd302005-11-08 21:11:33 +0000[diff] [blame]266</div>
267
268<div class="doc_text">
269
270<ul>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]271<li>The X86 backend does not yet support <a href="http://llvm.org/PR879">inline
Chris Lattner98a33492007-05-09 04:58:11 +0000[diff] [blame]272 assembly that uses the X86 floating point stack</a>.</li>
Chris Lattner8e061162007-09-26 06:01:35 +0000[diff] [blame]273<li>The X86 backend occasionally has <a href="http://llvm.org/PR1649">alignment
274 problems</a> on operating systems that don't require 16-byte stack alignment
275 (including most non-darwin OS's like linux).</li>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]276</ul>
277
278</div>
279
280<!-- ======================================================================= -->
281<div class="doc_subsection">
282 <a name="ppc-be">Known problems with the PowerPC back-end</a>
283</div>
284
285<div class="doc_text">
286
287<ul>
Nicolas Geoffray77d99502007-05-15 09:21:28 +0000[diff] [blame]288<li>The Linux PPC32/ABI support needs testing for the interpreter and static
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]289compilation, and lacks support for debug information.</li>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]290</ul>
291
292</div>
293
294<!-- ======================================================================= -->
295<div class="doc_subsection">
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]296 <a name="arm-be">Known problems with the ARM back-end</a>
297</div>
298
299<div class="doc_text">
300
301<ul>
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]302<li>Thumb mode works only on ARMv6 or higher processors. On sub-ARMv6
Duncan Sands47fc0a22007-09-26 15:59:54 +0000[diff] [blame]303processors, thumb programs can crash or produce wrong
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]304results (<a href="http://llvm.org/PR1388">PR1388</a>).</li>
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]305<li>Compilation for ARM Linux OABI (old ABI) is supported, but not fully tested.
306</li>
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]307<li>There is a bug in QEMU-ARM (<= 0.9.0) which causes it to incorrectly execute
308programs compiled with LLVM. Please use more recent versions of QEMU.</li>
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]309</ul>
310
311</div>
312
313<!-- ======================================================================= -->
314<div class="doc_subsection">
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]315 <a name="sparc-be">Known problems with the SPARC back-end</a>
316</div>
317
318<div class="doc_text">
319
320<ul>
321<li>The SPARC backend only supports the 32-bit SPARC ABI (-m32), it does not
322 support the 64-bit SPARC ABI (-m64).</li>
323</ul>
324
325</div>
326
327<!-- ======================================================================= -->
328<div class="doc_subsection">
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]329 <a name="alpha-be">Known problems with the Alpha back-end</a>
330</div>
331
332<div class="doc_text">
333
334<ul>
335
336<li>On 21164s, some rare FP arithmetic sequences which may trap do not have the
337appropriate nops inserted to ensure restartability.</li>
338
John Criswell3bdbd302005-11-08 21:11:33 +0000[diff] [blame]339</ul>
340</div>
341
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]342<!-- ======================================================================= -->
343<div class="doc_subsection">
344 <a name="ia64-be">Known problems with the IA64 back-end</a>
345</div>
346
347<div class="doc_text">
348
349<ul>
350
351<li>C++ programs are likely to fail on IA64, as calls to <tt>setjmp</tt> are
352made where the argument is not 16-byte aligned, as required on IA64. (Strictly
353speaking this is not a bug in the IA64 back-end; it will also be encountered
354when building C++ programs using the C back-end.)</li>
355
356<li>The C++ front-end does not use <a href="http://llvm.org/PR406">IA64
357ABI compliant layout of v-tables</a>. In particular, it just stores function
358pointers instead of function descriptors in the vtable. This bug prevents
359mixing C++ code compiled with LLVM with C++ objects compiled by other C++
360compilers.</li>
361
362<li>There are a few ABI violations which will lead to problems when mixing LLVM
363output with code built with other compilers, particularly for floating-point
364programs.</li>
365
366<li>Defining vararg functions is not supported (but calling them is ok).</li>
367
Chris Lattner98a33492007-05-09 04:58:11 +0000[diff] [blame]368<li>The Itanium backend has bitrotted somewhat.</li>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]369</ul>
370
371</div>
372
373<!-- ======================================================================= -->
374<div class="doc_subsection">
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]375 <a name="c-be">Known problems with the C back-end</a>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]376</div>
377
378<div class="doc_text">
379
380<ul>
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]381<li><a href="http://llvm.org/PR802">The C backend does not support inline
382 assembly code</a>.</li>
Chris Lattner8e061162007-09-26 06:01:35 +0000[diff] [blame]383<li><a href="http://llvm.org/PR1126">The C backend does not support vectors
384 yet</a>.</li>
Chris Lattner8e061162007-09-26 06:01:35 +0000[diff] [blame]385<li><a href="http://llvm.org/PR1658">The C backend violates the ABI of common
386 C++ programs</a>, preventing intermixing between C++ compiled by the CBE and
387 C++ code compiled with LLC or native compilers.</li>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]388</ul>
389
390</div>
John Criswell3bdbd302005-11-08 21:11:33 +0000[diff] [blame]391
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]392
393<!-- ======================================================================= -->
394<div class="doc_subsection">
395 <a name="c-fe">Known problems with the C front-end</a>
396</div>
Chris Lattner178f3db2003-10-02 05:07:23 +0000[diff] [blame]397
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]398<!-- _______________________________________________________________________ -->
Chris Lattner5a8a7282003-12-14 05:03:43 +0000[diff] [blame]399<div class="doc_subsubsection">Bugs</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]400
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]401<div class="doc_text">
Chris Lattner72a269f2006-03-03 00:34:26 +0000[diff] [blame]402
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]403<p>llvm-gcc4 does not currently support <a href="http://llvm.org/PR869">Link-Time
404Optimization</a> on most platforms "out-of-the-box". Please inquire on the
405llvmdev mailing list if you are interested.</p>
Chris Lattner44124232006-08-08 17:27:28 +0000[diff] [blame]406
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]407</div>
408
409<!-- _______________________________________________________________________ -->
410<div class="doc_subsubsection">
411 Notes
412</div>
413
414<div class="doc_text">
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]415<ul>
416
Chris Lattner2f131fe2007-05-17 22:02:24 +0000[diff] [blame]417<li><p>llvm-gcc does <b>not</b> support <tt>__builtin_apply</tt> yet.
418 See <a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</p>
419</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]420
Duncan Sandsea7a3262007-05-18 09:04:20 +0000[diff] [blame]421<li><p>llvm-gcc <b>partially</b> supports these GCC extensions:</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]422 <ol>
Duncan Sands47fc0a22007-09-26 15:59:54 +0000[diff] [blame]423 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Nested-Functions.html#Nested%20Functions">Nested Functions</a>:
424
425 As in Algol and Pascal, lexical scoping of functions.
426 Nested functions are supported, but llvm-gcc does not support
Duncan Sands755d9302007-09-26 16:24:52 +0000[diff] [blame]427 taking the address of a nested function (except on the X86-32 target)
Duncan Sands47fc0a22007-09-26 15:59:54 +0000[diff] [blame]428 or non-local gotos.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]429
430 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html#Function%20Attributes">Function Attributes</a>:
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]431
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]432 Declaring that functions have no side effects or that they can never
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]433 return.<br>
434
Anton Korobeynikovb8a47242007-11-16 11:12:01 +0000[diff] [blame]435 <b>Supported:</b> <tt>alias</tt>, <tt>always_inline</tt>, <tt>cdecl</tt>,
436 <tt>const</tt>, <tt>constructor</tt>, <tt>destructor</tt>,
Anton Korobeynikove7cbbfc2006-11-18 08:04:48 +0000[diff] [blame]437 <tt>deprecated</tt>, <tt>fastcall</tt>, <tt>format</tt>,
Anton Korobeynikovb8a47242007-11-16 11:12:01 +0000[diff] [blame]438 <tt>format_arg</tt>, <tt>non_null</tt>, <tt>noinline</tt>,
439 <tt>noreturn</tt>, <tt>pure</tt>, <tt>regparm</tt>
Anton Korobeynikovc7f9f3d2007-01-23 12:35:46 +0000[diff] [blame]440 <tt>section</tt>, <tt>stdcall</tt>, <tt>unused</tt>, <tt>used</tt>,
441 <tt>visibility</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]442
Anton Korobeynikovb8a47242007-11-16 11:12:01 +0000[diff] [blame]443 <b>Ignored:</b> <tt>nothrow</tt>, <tt>malloc</tt>,
444 <tt>no_instrument_function</tt></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]445 </ol>
Chris Lattner2f131fe2007-05-17 22:02:24 +0000[diff] [blame]446</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]447
Chris Lattner2f131fe2007-05-17 22:02:24 +0000[diff] [blame]448<li><p>llvm-gcc supports the vast majority of GCC extensions, including:</p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]449
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]450 <ol>
Chris Lattner2f131fe2007-05-17 22:02:24 +0000[diff] [blame]451 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Pragmas.html#Pragmas">Pragmas</a>: Pragmas accepted by GCC.</li>
452 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Local-Labels.html#Local%20Labels">Local Labels</a>: Labels local to a block.</li>
453 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
454 Other built-in functions.</li>
455 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
456 Specifying attributes of variables.</li>
457 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Type-Attributes.html#Type%20Attributes">Type Attributes</a>: Specifying attributes of types.</li>
458 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread_002dLocal.html">Thread-Local</a>: Per-thread variables.</li>
459 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
460 Arrays whose length is computed at run time.</li>
Chris Lattnerd3dc8502004-03-16 08:54:07 +0000[diff] [blame]461 <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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]462 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
463 <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 Lattnerce33a1b2004-06-22 03:48:17 +0000[diff] [blame]464 <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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]465 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
466 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
467 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
468 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
469 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
470 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
471 <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>
472 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]473 <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>
474 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constraints.html#Constraints">Constraints</a>: Constraints for asm operands.</li>
475 <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>
476 <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>
477 <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>
478 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Target-Builtins.html#Target%20Builtins">Target Builtins</a>: Built-in functions specific to particular targets.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]479 <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 Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]480 <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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]481 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Initializers.html#Initializers">Initializers</a>: Non-constant initializers.</li>
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]482 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
483or arrays as values.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]484 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Designated-Inits.html#Designated%20Inits">Designated Inits</a>: Labeling elements of initializers.</li>
Misha Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]485 <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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]486 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
487 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
488 <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 Lattner7591b822004-12-08 18:29:38 +0000[diff] [blame]489 <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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]490 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
491 <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>
492 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
493 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
494 <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>
495 <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>
496 <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 Lattner3646dad2004-02-14 04:08:29 +0000[diff] [blame]497 <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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]498 <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>
499 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Attribute-Syntax.html#Attribute%20Syntax">Attribute Syntax</a>: Formal syntax for attributes.</li>
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]500 </ol></li>
501
502</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]503
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]504<p>If you run into GCC extensions which have not been included in any of these
505lists, please let us know (also including whether or not they work).</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]506
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]507</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]508
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]509<!-- ======================================================================= -->
510<div class="doc_subsection">
511 <a name="c++-fe">Known problems with the C++ front-end</a>
512</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]513
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]514<div class="doc_text">
515
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]516<p>The C++ front-end is considered to be fully
Chris Lattnerb5bb5972004-12-07 08:04:13 +0000[diff] [blame]517tested and works for a number of non-trivial programs, including LLVM
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]518itself, Qt, Mozilla, etc.</p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]519
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]520<ul>
Chris Lattner7422bce2008-02-06 06:30:34 +0000[diff] [blame]521<li>Exception handling only works well on the X86 and PowerPC targets.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]522</ul>
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]523
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]524</div>
525
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]526
Chris Lattnerb62a5f02005-05-15 16:01:20 +0000[diff] [blame]527
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]528<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]529<div class="doc_section">
530 <a name="additionalinfo">Additional Information</a>
531</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]532<!-- *********************************************************************** -->
533
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]534<div class="doc_text">
535
Chris Lattnercb5596d2005-05-16 17:13:10 +0000[diff] [blame]536<p>A wide variety of additional information is available on the <a
Chris Lattnere0c1df42007-05-18 00:44:29 +0000[diff] [blame]537href="http://llvm.org">LLVM web page</a>, in particular in the <a
538href="http://llvm.org/docs/">documentation</a> section. The web page also
Reid Spencerc7f87f22007-07-09 08:04:31 +0000[diff] [blame]539contains versions of the API documentation which is up-to-date with the
540Subversion version of the source code.
Misha Brukman96158092005-03-30 19:14:24 +0000[diff] [blame]541You can access versions of these documents specific to this release by going
542into the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]543
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]544<p>If you have any questions or comments about LLVM, please feel free to contact
Chris Lattnera69595e2005-10-29 07:07:09 +0000[diff] [blame]545us via the <a href="http://llvm.org/docs/#maillist"> mailing
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]546lists</a>.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]547
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]548</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]549
550<!-- *********************************************************************** -->
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]551
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]552<hr>
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]553<address>
Misha Brukman8834af92003-12-21 22:53:21 +0000[diff] [blame]554 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]555 src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
556 <a href="http://validator.w3.org/check/referer"><img
557 src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a>
558
Chris Lattnere0c1df42007-05-18 00:44:29 +0000[diff] [blame]559 <a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]560 Last modified: $Date$
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]561</address>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]562
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]563</body>
564</html>