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Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
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Chris Lattner2974b5b2004-04-01 00:41:31 +0000[diff] [blame]6 <title>LLVM 1.3 Release Notes</title>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]7</head>
8<body>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]9
Chris Lattner2974b5b2004-04-01 00:41:31 +0000[diff] [blame]10<div class="doc_title">LLVM 1.3 Release Notes</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]11
12<ol>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]13 <li><a href="#intro">Introduction</a></li>
14 <li><a href="#whatsnew">What's New?</a></li>
Chris Lattner4b538b92004-04-30 22:17:12 +0000[diff] [blame]15 <li><a href="GettingStarted.html">Installation Instructions</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]16 <li><a href="#portability">Portability and Supported Platforms</a></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]17 <li><a href="#knownproblems">Known Problems</a>
18 <ul>
Chris Lattner2974b5b2004-04-01 00:41:31 +0000[diff] [blame]19 <li><a href="#experimental">Experimental features included in this
20 release</a>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]21 <li><a href="#core">Known problems with the LLVM Core</a>
22 <li><a href="#c-fe">Known problems with the C Front-end</a>
23 <li><a href="#c++-fe">Known problems with the C++ Front-end</a>
24 <li><a href="#x86-be">Known problems with the X86 Back-end</a>
25 <li><a href="#sparc-be">Known problems with the Sparc Back-end</a>
26 <li><a href="#c-be">Known problems with the C back-end</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]27 </ul></li>
28 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]29</ol>
30
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]31<div class="doc_text">
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]32 <p><b>Written by the <a href="http://llvm.cs.uiuc.edu">LLVM team</a></b><p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]33</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]34
35<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]36<div class="doc_section">
37 <a name="intro">Introduction</a>
38</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]39<!-- *********************************************************************** -->
40
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]41<div class="doc_text">
42
43<p>This document contains the release notes for the LLVM compiler
Chris Lattner2974b5b2004-04-01 00:41:31 +0000[diff] [blame]44infrastructure, release 1.3. Here we describe the status of LLVM, including any
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]45known problems and bug fixes from the previous release. The most up-to-date
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]46version of this document can be found on the <a
Chris Lattner2974b5b2004-04-01 00:41:31 +0000[diff] [blame]47href="http://llvm.cs.uiuc.edu/releases/1.3/">LLVM 1.3 web site</a>. If you are
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]48not reading this on the LLVM web pages, you should probably go there because
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]49this document may be updated after the release.</p>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]50
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]51<p>For more information about LLVM, including information about potentially more
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]52current releases, please check out the <a href="http://llvm.cs.uiuc.edu">main
53web site</a>. If you have questions or comments, the <a
54href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM developer's mailing
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]55list</a> is a good place to send them.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]56
Chris Lattner9e848092003-12-12 04:25:33 +0000[diff] [blame]57<p>Note that if you are reading this file from CVS, this document applies
58to the <i>next</i> release, not the current one. To see the release notes for
59the current or previous releases, see the <a
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]60href="http://llvm.cs.uiuc.edu/releases/">releases page</a>.</p>
61
62</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]63
64<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]65<div class="doc_section">
66 <a name="whatsnew">What's New?</a>
67</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]68<!-- *********************************************************************** -->
69
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]70<div class="doc_text">
71
Chris Lattnera39719f2004-02-25 16:36:51 +0000[diff] [blame]72<p>
Chris Lattnerd4594dc2004-05-04 17:04:09 +0000[diff] [blame]73This is the fourth public release of the LLVM compiler infrastructure. This
74release primarily improves the <a href="#codequality">performance of the
75code</a> produced by all aspects of the LLVM compiler and adds some <a
76href="#newfeatures">new features</a>, though it does <a href="#bugfix">fix a few
77bugs</a> as well.
Chris Lattnerb40efb32003-12-14 05:03:43 +0000[diff] [blame]78</p>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]79
Chris Lattner835104c2004-03-17 03:54:41 +0000[diff] [blame]80<p>
81At this time, LLVM is known to correctly compile and run all C &amp; C++ SPEC
82CPU2000 benchmarks, the Olden benchmarks, and the Ptrdist benchmarks. It has
83also been used to compile <b>many</b> other programs. LLVM now also works with
84a broad variety of C++ programs, though it has still received less testing than
85the C front-end.
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]86</p>
87
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]88<!--=========================================================================-->
89<div class="doc_subsubsection">
Chris Lattnera39719f2004-02-25 16:36:51 +0000[diff] [blame]90<a name="newfeatures">This release implements the following new features:</a>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]91</div>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]92
93<ol>
Chris Lattner2974b5b2004-04-01 00:41:31 +0000[diff] [blame]94<li>The LLVM <a href="LangRef.html#i_select"><tt>select</tt></a> instruction is
Chris Lattner6e1ef192004-05-02 04:19:15 +0000[diff] [blame]95now fully implemented and supported by all transformations, native code
96generators, and the interpreter.</li>
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]97<li>Bugpoint can now narrow down code-generation bugs to a loop nest, where
98before it could only narrow them down to a function being miscompiled.</li>
Brian Gaeke43be3112004-05-04 21:22:57 +0000[diff] [blame]99<li><a href="http://llvm.cs.uiuc.edu/PR40">Bugpoint can now debug arbitrary
100modes of llc</a> and lli, by passing them command line flags (e.g.,
101<tt>-regalloc=linearscan</tt>, <tt>-enable-correct-eh-support</tt>, etc.) </li>
Chris Lattner6e1ef192004-05-02 04:19:15 +0000[diff] [blame]102<li>The Control Flow Graph in the native code generators is no longer
103constrained to be the same as the CFG for the LLVM input code.</li>
104<li>The LLVM induction variable analysis routines have been rewritten.</li>
105<li>LLVM now has new loop unrolling and loop unswitching passes.</li>
106<li>The induction variable substitution pass performs linear function test
107replacement and exit value replacement optimizations.</li>
Chris Lattner55ee0312003-11-19 22:05:38 +0000[diff] [blame]108</ol>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]109
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]110
111<!--=========================================================================-->
112<div class="doc_subsubsection">
113In this release, the following missing features were implemented:
114</div>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]115
116<ol>
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]117<li><a href="http://llvm.cs.uiuc.edu/PR82">LLVM cannot handle structures with
118more than 256 elements</a></li>
Misha Brukmancb003362004-04-19 03:01:01 +0000[diff] [blame]119<li><a href="http://llvm.cs.uiuc.edu/PR38">[bugpoint] External functions used in
120non-instruction entities, such as global constant initializer</a></li>
121<li><a href="http://llvm.cs.uiuc.edu/PR290">Bugpoint doesn't support
122uses of external fns by immediate constant exprs</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]123</ol>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]124
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]125
126<!--=========================================================================-->
127<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]128<a name="qualityofimp">In this release, the following Quality of Implementation
129issues were fixed:</a>
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]130</div>
131
132<ol>
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]133<li><a href="http://llvm.cs.uiuc.edu/PR305">LLVM tools will happily spew
134bytecode onto your terminal</a></li>
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]135</ol>
136
137<!--=========================================================================-->
138<div class="doc_subsubsection">
Chris Lattnera39719f2004-02-25 16:36:51 +0000[diff] [blame]139In this release, the following build problems were fixed:
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]140</div>
141
142<ol>
Brian Gaeke21a710a2004-04-20 18:18:46 +0000[diff] [blame]143<li><a href="http://llvm.cs.uiuc.edu/PR301">Minor configure bugs with -disable/enable-povray and -disable-spec</a></li>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]144</ol>
145
146<!--=========================================================================-->
147<div class="doc_subsubsection">
Chris Lattner6e1ef192004-05-02 04:19:15 +0000[diff] [blame]148<a name="codequality">This release includes the following Code Quality
149improvements:</a>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]150</div>
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]151
152<ol>
Chris Lattner6e1ef192004-05-02 04:19:15 +0000[diff] [blame]153<li>Fixed: <a href="http://llvm.cs.uiuc.edu/PR309">[vmcore] Code quality problem
154due to long operand of getelementptr</a></li>
Chris Lattner64913402004-04-13 14:43:35 +0000[diff] [blame]155
156<li>The X86 backend now generates substantially better code for 64-bit integer
157and floating point operations.</li>
158
159<li>The -inline pass no longer inlines mutually recursive functions until it
160hits the inlining threshold.</li>
161
162<li>The -inline pass no longer misses obvious inlining opportunities just
163because the callee eventually calls into an external function.</li>
164
165<li>The -simplifycfg pass can now "if convert" simple statements into the new
166<tt>select</tt> instruction.</li>
167
168<li>The -loopsimplify pass can now break <a
169href="http://llvm.cs.uiuc.edu/PR35">natural loops with multiple backedges</a>
170into multiple nested loops. This enables a variety of subsequent
171optimizations.</li>
172
173<li>The -adce pass can now eliminate calls to functions that do not not write to
174memory.</li>
175
176<li>The link-time optimizer now runs the -prune-eh pass (to remove unused
Chris Lattnerd4594dc2004-05-04 17:04:09 +0000[diff] [blame]177exception handlers).</li>
Chris Lattner64913402004-04-13 14:43:35 +0000[diff] [blame]178
Chris Lattner6e1ef192004-05-02 04:19:15 +0000[diff] [blame]179<li>The -simplifycfg pass can now eliminate simple correlated branches (such as
180"<tt>if (A &lt; B &amp;&amp; A &lt; B)</tt>", and can turn short-circuiting
181operators into the strict versions when useful (such as "<tt>if (A &lt; B || A
182&gt; C)</tt>" into "<tt>if (A &lt; B | A &gt; C)</tt>"</li>
183
Chris Lattnerd4594dc2004-05-04 17:04:09 +0000[diff] [blame]184<li>LLVM now has infrastructure for (simple and sparse conditional) constant
185propagation of function calls. It currently supports a few math library
186functions like sqrt/sin/cos/etc.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]187</ol>
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]188
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]189
190<!--=========================================================================-->
191<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]192<a name="bugfix">In this release, the following bugs in the previous release
193were fixed:</a>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]194</div>
195
196<p>Bugs in the LLVM Core:</p>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]197
198<ol>
John Criswell4d8d49f2004-05-06 22:23:24 +0000[diff] [blame]199<li><a href="http://llvm.cs.uiuc.edu/PR330">[vmcore] Linker causes erroneous
200asssertion</a></li>
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]201<li><a href="http://llvm.cs.uiuc.edu/PR306">[loopsimplify] Loop simplify
202incorrectly updates dominator information</a></li>
203<li><a href="http://llvm.cs.uiuc.edu/PR310">[tailduplicate] DemoteRegToStack
204breaks SSA form</a></li>
205<li><a href="http://llvm.cs.uiuc.edu/PR313">[X86] JIT miscompiles unsigned short
206to floating point cast</a></li>
Chris Lattnerd4594dc2004-05-04 17:04:09 +0000[diff] [blame]207<li><a href="http://llvm.cs.uiuc.edu/PR332">[adce] Crash handling unreachable code that unwinds</a></li>
Brian Gaeke43be3112004-05-04 21:22:57 +0000[diff] [blame]208<li><a href="http://llvm.cs.uiuc.edu/PR333">[sparc] LLC can't emit 2 functions of
209the same name, both having constant pools</a></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]210</ol>
211
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]212<p>Bugs in the C/C++ front-end:</p>
213
214<ol>
Chris Lattner581dc802004-05-07 18:40:38 +0000[diff] [blame^]215<li><a href="http://llvm.cs.uiuc.edu/PR326">[llvmgcc] Crash on use of undeclared enum type</a></li>
216<li><a href="http://llvm.cs.uiuc.edu/PR298">[llvmgcc] Variable length array indexing miscompiled</a></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]217</ol>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]218
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]219</div>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]220
221<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]222<div class="doc_section">
223 <a name="portability">Portability and Supported Platforms</a>
224</div>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]225<!-- *********************************************************************** -->
226
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]227<div class="doc_text">
228
229<p>LLVM has been extensively tested on Intel and AMD machines running Red
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]230Hat Linux and FreeBSD. It has also been tested on Sun UltraSPARC workstations
231running Solaris 8. Additionally, LLVM works on Mac OS X 10.3 and above, but
232only with the C backend or interpreter (no native backend for the PowerPC is
233available yet). The core LLVM infrastructure uses "autoconf" for portability,
234so hopefully we work on more platforms than that. However, it is likely that we
235missed something and that minor porting is required to get LLVM to work on new
236platforms. We welcome portability patches and error messages.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]237
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]238</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]239
Brian Gaeke21a710a2004-04-20 18:18:46 +0000[diff] [blame]240<!--=========================================================================-->
241<div class="doc_subsection">
242In this release, the following portability problems were fixed:
243</div>
244
245<ol>
246<li><a href="http://llvm.cs.uiuc.edu/PR304">warnings compiling Stacker compiler on Mac OS X</a></li>
Chris Lattnerd4594dc2004-05-04 17:04:09 +0000[diff] [blame]247<li><a href="http://llvm.cs.uiuc.edu/PR308">Archive file reader doesn't understand abbreviated names in headers</a></li>
Brian Gaeke21a710a2004-04-20 18:18:46 +0000[diff] [blame]248</ol>
249
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]250<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]251<div class="doc_section">
252 <a name="knownproblems">Known Problems</a>
253</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]254<!-- *********************************************************************** -->
255
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]256<div class="doc_text">
257
258<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]259component. As new problems are discovered, they will be added to these
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]260sections. If you run into a problem, please check the <a
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]261href="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]262there isn't already one.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]263
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]264</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]265
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]266<!-- ======================================================================= -->
267<div class="doc_subsection">
268 <a name="experimental">Experimental features included with this release</a>
269</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]270
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]271<div class="doc_text">
272
273<p>
274The following components of this LLVM release are either untested, known to be
275broken or unreliable, or are in early development. These components should not
276be relied on, and bugs should not be filed against them, but they may be useful
277to some people. In particular, if you would like to work on one of these
278components, please contact us on the llvmdev list.
279</p>
280
281<ul>
282<li>The following passes are incomplete or buggy: <tt>-pgmdep, -memdep,
283 -ipmodref, -sortstructs, -swapstructs, -cee</tt></li>
284
285<li>The <tt>-pre</tt> pass is incomplete (there are cases it doesn't handle that
286 it should) and not thoroughly tested.</li>
287<li>The <tt>llvm-ar</tt> tool is incomplete and probably buggy.</li>
288<li>The <tt>llvm-db</tt> tool is in a very early stage of development.</li>
289</ul>
290
291</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]292
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]293<!-- ======================================================================= -->
294<div class="doc_subsection">
295 <a name="core">Known problems with the LLVM Core</a>
296</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]297
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]298<div class="doc_text">
299
300<ul>
301
302<li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not
303work.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]304
305<li>The JIT does not use mutexes to protect its internal data structures. As
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]306such, execution of a threaded program could cause these data structures to be
307corrupted.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]308
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]309<li>It is not possible to <tt>dlopen</tt> an LLVM bytecode file in the JIT.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]310
Chris Lattnere84843b2003-10-20 19:05:03 +0000[diff] [blame]311<li>Linking in static archive files (.a files) is very slow (there is no symbol
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]312table in the archive).</li>
Chris Lattner2855ecd2003-11-04 20:06:53 +0000[diff] [blame]313
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]314<li>The gccld program <a href="http://llvm.cs.uiuc.edu/PR139">does not link
315objects/archives in the order specified on the command line.</a></li>
Chris Lattner2e6fcaf2004-02-15 23:09:07 +0000[diff] [blame]316
317<li><a href="http://llvm.cs.uiuc.edu/PR240">The lower-invoke pass does not mark
John Criswelld46c6962004-03-12 21:29:42 +0000[diff] [blame]318values live across a setjmp as volatile</a>. This missing feature only affects
Chris Lattner2e6fcaf2004-02-15 23:09:07 +0000[diff] [blame]319targets whose setjmp/longjmp libraries do not save and restore the entire
320register file.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]321</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]322</div>
323
324<!-- ======================================================================= -->
325<div class="doc_subsection">
326 <a name="c-fe">Known problems with the C front-end</a>
327</div>
Chris Lattner47588f92003-10-02 05:07:23 +0000[diff] [blame]328
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]329<!-- _______________________________________________________________________ -->
Chris Lattnerb40efb32003-12-14 05:03:43 +0000[diff] [blame]330<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]331
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]332<div class="doc_text">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]333<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]334<li>C99 Variable sized arrays do not release stack memory when they go out of
335 scope. Thus, the following program may run out of stack space:
336<pre>
337 for (i = 0; i != 1000000; ++i) {
338 int X[n];
339 foo(X);
340 }
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]341</pre></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]342
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]343<li>
344Initialization of global union variables can only be done
345<a href="http://llvm.cs.uiuc.edu/bugs/show_bug.cgi?id=162">with the largest
346union member</a>.
347</li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]348
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]349<li><a href="http://llvm.cs.uiuc.edu/PR244">[llvm-gcc] Error when an implicitly
350external function is re-declared as static</a></li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]351
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]352</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]353</div>
354
355<!-- _______________________________________________________________________ -->
356<div class="doc_subsubsection">
357 Notes
358</div>
359
360<div class="doc_text">
361
362<ul>
363
364<li>Inline assembly is not yet supported.</li>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]365
366<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]367support for floating point data types of any size other than 32 and 64
368bits.</li>
369
370<li>The following Unix system functionality has not been tested and may not
371work:
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]372 <ol>
373 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
374 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
375 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
376 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
377 - These functions have not been tested.
378 </ol></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]379
380<li>Although many GCC extensions are supported, some are not. In particular,
381 the following extensions are known to <b>not be</b> supported:
382 <ol>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]383 <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]384 <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>
385 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
386 <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]387 <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]388 <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>
389 <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]390 <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>
391 <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>
392 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables.</li>
393 <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]394 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]395
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]396 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]397 attribute means that the LLVM compiler ignores the presence of the attribute,
398 but the code should still work. An unsupported attribute is one which is
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]399 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]400 the program.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]401
402 <ol>
403 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
404 Arrays whose length is computed at run time.<br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]405 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]406
407 <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]408
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]409 Declaring that functions have no side effects or that they can never
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]410 return.<br>
411
412 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
413 <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>,
414 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
415
416 <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>,
417 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
418 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
419
420 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
421 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
422 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]423
424 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
425 Specifying attributes of variables.<br>
426 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
427 <tt>deprecated</tt>, <tt>transparent_union</tt>,
428 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]429
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]430 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
431 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
432 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]433 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]434
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]435 <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]436 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]437 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]438
439 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
440 all target specific attributes.</li>
441
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]442 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
443 Other built-in functions.<br>
444 We support all builtins which have a C language equivalent (e.g.,
445 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
446 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]447 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt> (ignored).</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]448
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]449 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]450
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]451 <p>The following extensions <b>are</b> known to be supported:</p>
452
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]453 <ol>
Chris Lattner7fe97dd2004-03-16 08:54:07 +0000[diff] [blame]454 <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]455 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
456 <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>
457 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Lvalues.html#Lvalues">Lvalues</a>: Using <code>?:</code>, "<code>,</code>" and casts in lvalues.</li>
458 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
459 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
460 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
461 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
462 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
463 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
464 <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>
465 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
466 <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]467 <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]468 <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]469 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
470or arrays as values.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]471 <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]472 <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]473 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
474 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
475 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li>
476 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C---Comments.html#C++%20Comments">C++ Comments</a>: C++ comments are recognized.</li>
477 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
478 <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>
479 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
480 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
481 <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>
482 <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>
483 <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]484 <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]485 <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>
486 <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]487 </ol></li>
488
489</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]490
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]491<p>If you run into GCC extensions which have not been included in any of these
492lists, please let us know (also including whether or not they work).</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]493
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]494</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]495
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]496<!-- ======================================================================= -->
497<div class="doc_subsection">
498 <a name="c++-fe">Known problems with the C++ front-end</a>
499</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]500
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]501<div class="doc_text">
502
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]503<p>For this release, the C++ front-end is considered to be fully functional but
Chris Lattner9e848092003-12-12 04:25:33 +0000[diff] [blame]504has not been tested as thoroughly as the C front-end. It has been tested and
505works for a number of non-trivial programs, but there may be lurking bugs.
506Please report any bugs or problems.</p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]507
508</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]509
510<!-- _______________________________________________________________________ -->
Chris Lattner3a51be12004-02-14 04:12:41 +0000[diff] [blame]511<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]512
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]513<div class="doc_text">
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]514
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]515<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]516<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]517 front-end</a>.</li>
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]518</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]519</div>
520
521<!-- _______________________________________________________________________ -->
522<div class="doc_subsubsection">
523 Notes
524</div>
525
526<div class="doc_text">
527
528<ul>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]529
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]530<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
531parser is significantly more standards compliant (and picky) than prior GCC
532versions. For more information, see the C++ section of the <a
Chris Lattner9e848092003-12-12 04:25:33 +0000[diff] [blame]533href="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]534
535<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]536 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]537 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]538 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]539 better than most compilers).</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]540
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]541<li>The LLVM C++ front-end follows the <a
542 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
543 This document, which is not Itanium specific, specifies a standard for name
544 mangling, class layout, v-table layout, RTTI formats, and other C++
545 representation issues. Because we use this API, code generated by the LLVM
546 compilers should be binary compatible with machine code generated by other
547 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
548 <i>However</i>, the exception handling mechanism used by LLVM is very
549 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]550 interact correctly</b>. </li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]551
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]552</ul>
Chris Lattnerfcc54b32003-10-07 22:14:37 +0000[diff] [blame]553
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]554</div>
555
556<!-- ======================================================================= -->
557<div class="doc_subsection">
558 <a name="x86-be">Known problems with the X86 back-end</a>
559</div>
560
561<div class="doc_text">
562
563<ul>
Chris Lattnerde4afdc2004-02-08 22:23:33 +0000[diff] [blame]564<li>None so far.
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]565</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]566
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]567</div>
568
569<!-- ======================================================================= -->
570<div class="doc_subsection">
571 <a name="sparc-be">Known problems with the Sparc back-end</a>
572</div>
573
574<div class="doc_text">
575
576<ul>
Chris Lattner6a39aa52004-03-19 19:22:28 +0000[diff] [blame]577<li>There are several programs in the LLVM testsuite that the Sparc code generator is known to miscompile.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]578</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]579
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]580</div>
581
582<!-- ======================================================================= -->
583<div class="doc_subsection">
584 <a name="c-be">Known problems with the C back-end</a>
585</div>
586
587<div class="doc_text">
588
589<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]590
591<li>The C back-end produces code that violates the ANSI C Type-Based Alias
592Analysis rules. As such, special options may be necessary to compile the code
593(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]594problem probably cannot be fixed.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]595
Chris Lattnere84843b2003-10-20 19:05:03 +0000[diff] [blame]596<li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]597cannot include special floating point numbers like Not-A-Number or
598Infinity.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]599
Chris Lattner2855ecd2003-11-04 20:06:53 +0000[diff] [blame]600<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]601supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]602frontends.</li>
Chris Lattner2af46052003-10-24 04:03:19 +0000[diff] [blame]603
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]604</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]605
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]606</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]607
608<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]609<div class="doc_section">
610 <a name="additionalinfo">Additional Information</a>
611</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]612<!-- *********************************************************************** -->
613
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]614<div class="doc_text">
615
616<p>A wide variety of additional information is available on the LLVM web page,
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]617including mailing lists and publications describing algorithms and components
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]618implemented in LLVM. The web page also contains versions of the API
619documentation which is up-to-date with the CVS version of the source code. You
620can access versions of these documents specific to this release by going into
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]621the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]622
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]623<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]624us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing
625lists</a>.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]626
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]627</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]628
629<!-- *********************************************************************** -->
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]630
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]631<hr>
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]632<address>
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637
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]638 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]639 Last modified: $Date$
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]640</address>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]641
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]642</body>
643</html>