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gerrit-public.fairphone.software / toolchain / llvm-project / 4cf17775e8354b0fd17a7a6344ba6ccc94ed4ced / . / llvm / docs / ReleaseNotes.html
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Chris Lattner1a7e43c2004-04-01 00:41:31 +0000[diff] [blame]6 <title>LLVM 1.3 Release Notes</title>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]7</head>
8<body>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]9
Chris Lattner1a7e43c2004-04-01 00:41:31 +0000[diff] [blame]10<div class="doc_title">LLVM 1.3 Release Notes</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]11
12<ol>
Misha Brukman80731b92003-11-22 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 Lattner77a51732004-04-30 22:17:12 +0000[diff] [blame]15 <li><a href="GettingStarted.html">Installation Instructions</a></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]16 <li><a href="#portability">Portability and Supported Platforms</a></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]17 <li><a href="#knownproblems">Known Problems</a>
18 <ul>
Chris Lattner1a7e43c2004-04-01 00:41:31 +0000[diff] [blame]19 <li><a href="#experimental">Experimental features included in this
20 release</a>
Chris Lattner3d482502003-10-02 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]27 </ul></li>
28 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]29</ol>
30
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]31<div class="doc_text">
John Criswell86a3a482003-12-18 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]33</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]34
35<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]36<div class="doc_section">
37 <a name="intro">Introduction</a>
38</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]39<!-- *********************************************************************** -->
40
Misha Brukman80731b92003-11-22 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 Lattner1a7e43c2004-04-01 00:41:31 +0000[diff] [blame]44infrastructure, release 1.3. Here we describe the status of LLVM, including any
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]45known problems and bug fixes from the previous release. The most up-to-date
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]46version of this document can be found on the <a
Chris Lattner1a7e43c2004-04-01 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 Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]48not reading this on the LLVM web pages, you should probably go there because
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]49this document may be updated after the release.</p>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]50
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]51<p>For more information about LLVM, including information about potentially more
Chris Lattnere7525b52003-10-07 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]55list</a> is a good place to send them.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]56
Chris Lattnere76e9ab2003-12-12 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]60href="http://llvm.cs.uiuc.edu/releases/">releases page</a>.</p>
61
62</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]63
64<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]65<div class="doc_section">
66 <a name="whatsnew">What's New?</a>
67</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]68<!-- *********************************************************************** -->
69
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]70<div class="doc_text">
71
Chris Lattner8ebf2532004-02-25 16:36:51 +0000[diff] [blame]72<p>
Chris Lattnerea309ff2004-05-04 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 Lattner5a8a7282003-12-14 05:03:43 +0000[diff] [blame]78</p>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]79
Chris Lattner28202352004-03-17 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 Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]86</p>
87
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]88<!--=========================================================================-->
89<div class="doc_subsubsection">
Chris Lattner8ebf2532004-02-25 16:36:51 +0000[diff] [blame]90<a name="newfeatures">This release implements the following new features:</a>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]91</div>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]92
93<ol>
Chris Lattner1a7e43c2004-04-01 00:41:31 +0000[diff] [blame]94<li>The LLVM <a href="LangRef.html#i_select"><tt>select</tt></a> instruction is
Chris Lattner2ad48782004-05-02 04:19:15 +0000[diff] [blame]95now fully implemented and supported by all transformations, native code
96generators, and the interpreter.</li>
Misha Brukman017f2f32004-04-19 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 Gaekee307f8a72004-05-04 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 Lattner2ad48782004-05-02 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 Lattner592db402003-11-19 22:05:38 +0000[diff] [blame]108</ol>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]109
Chris Lattnerba7bd472003-12-06 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 Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]115
116<ol>
Misha Brukman017f2f32004-04-19 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 Brukmane7050232004-04-19 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>
Reid Spencer45e25d82004-05-09 23:32:39 +0000[diff] [blame]121<li><a href="http://llvm.cs.uiuc.edu/PR178">Stacker does not handle targets
122with 64-bit pointers.</a></li>
Misha Brukmane7050232004-04-19 03:01:01 +0000[diff] [blame]123<li><a href="http://llvm.cs.uiuc.edu/PR290">Bugpoint doesn't support
124uses of external fns by immediate constant exprs</a></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]125</ol>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]126
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]127
128<!--=========================================================================-->
129<div class="doc_subsubsection">
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]130<a name="qualityofimp">In this release, the following Quality of Implementation
131issues were fixed:</a>
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]132</div>
133
134<ol>
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]135<li><a href="http://llvm.cs.uiuc.edu/PR305">LLVM tools will happily spew
136bytecode onto your terminal</a></li>
Chris Lattnercf5822a2004-05-07 19:23:05 +0000[diff] [blame]137<li><a href="http://llvm.cs.uiuc.edu/PR329">[llvmgcc] type names are not emitted for structure typedefs</a></li>
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]138</ol>
139
140<!--=========================================================================-->
141<div class="doc_subsubsection">
Chris Lattner8ebf2532004-02-25 16:36:51 +0000[diff] [blame]142In this release, the following build problems were fixed:
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]143</div>
144
145<ol>
Brian Gaeke86a6c752004-04-20 18:18:46 +0000[diff] [blame]146<li><a href="http://llvm.cs.uiuc.edu/PR301">Minor configure bugs with -disable/enable-povray and -disable-spec</a></li>
Brian Gaekee3e557e2004-05-09 05:28:35 +0000[diff] [blame]147<li><a href="http://llvm.cs.uiuc.edu/PR289">shell scripts output by gccld don't work if you change PATH</a></li>
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]148</ol>
149
150<!--=========================================================================-->
151<div class="doc_subsubsection">
Chris Lattner2ad48782004-05-02 04:19:15 +0000[diff] [blame]152<a name="codequality">This release includes the following Code Quality
153improvements:</a>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]154</div>
Chris Lattner639579c2003-10-27 17:06:39 +0000[diff] [blame]155
156<ol>
Chris Lattner2ad48782004-05-02 04:19:15 +0000[diff] [blame]157<li>Fixed: <a href="http://llvm.cs.uiuc.edu/PR309">[vmcore] Code quality problem
158due to long operand of getelementptr</a></li>
Chris Lattner54dcea82004-04-13 14:43:35 +0000[diff] [blame]159
160<li>The X86 backend now generates substantially better code for 64-bit integer
161and floating point operations.</li>
162
163<li>The -inline pass no longer inlines mutually recursive functions until it
164hits the inlining threshold.</li>
165
166<li>The -inline pass no longer misses obvious inlining opportunities just
167because the callee eventually calls into an external function.</li>
168
169<li>The -simplifycfg pass can now "if convert" simple statements into the new
170<tt>select</tt> instruction.</li>
171
172<li>The -loopsimplify pass can now break <a
173href="http://llvm.cs.uiuc.edu/PR35">natural loops with multiple backedges</a>
174into multiple nested loops. This enables a variety of subsequent
175optimizations.</li>
176
177<li>The -adce pass can now eliminate calls to functions that do not not write to
178memory.</li>
179
180<li>The link-time optimizer now runs the -prune-eh pass (to remove unused
Chris Lattnerea309ff2004-05-04 17:04:09 +0000[diff] [blame]181exception handlers).</li>
Chris Lattner54dcea82004-04-13 14:43:35 +0000[diff] [blame]182
Chris Lattner2ad48782004-05-02 04:19:15 +0000[diff] [blame]183<li>The -simplifycfg pass can now eliminate simple correlated branches (such as
184"<tt>if (A &lt; B &amp;&amp; A &lt; B)</tt>", and can turn short-circuiting
185operators into the strict versions when useful (such as "<tt>if (A &lt; B || A
186&gt; C)</tt>" into "<tt>if (A &lt; B | A &gt; C)</tt>"</li>
187
Chris Lattnerea309ff2004-05-04 17:04:09 +0000[diff] [blame]188<li>LLVM now has infrastructure for (simple and sparse conditional) constant
189propagation of function calls. It currently supports a few math library
190functions like sqrt/sin/cos/etc.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]191</ol>
Chris Lattner639579c2003-10-27 17:06:39 +0000[diff] [blame]192
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]193
194<!--=========================================================================-->
195<div class="doc_subsubsection">
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]196<a name="bugfix">In this release, the following bugs in the previous release
197were fixed:</a>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]198</div>
199
200<p>Bugs in the LLVM Core:</p>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]201
202<ol>
John Criswell6956afa2004-05-06 22:23:24 +0000[diff] [blame]203<li><a href="http://llvm.cs.uiuc.edu/PR330">[vmcore] Linker causes erroneous
204asssertion</a></li>
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]205<li><a href="http://llvm.cs.uiuc.edu/PR306">[loopsimplify] Loop simplify
206incorrectly updates dominator information</a></li>
207<li><a href="http://llvm.cs.uiuc.edu/PR310">[tailduplicate] DemoteRegToStack
208breaks SSA form</a></li>
209<li><a href="http://llvm.cs.uiuc.edu/PR313">[X86] JIT miscompiles unsigned short
210to floating point cast</a></li>
Chris Lattnerea309ff2004-05-04 17:04:09 +0000[diff] [blame]211<li><a href="http://llvm.cs.uiuc.edu/PR332">[adce] Crash handling unreachable code that unwinds</a></li>
Brian Gaekee307f8a72004-05-04 21:22:57 +0000[diff] [blame]212<li><a href="http://llvm.cs.uiuc.edu/PR333">[sparc] LLC can't emit 2 functions of
213the same name, both having constant pools</a></li>
Chris Lattnereefb8a72004-05-10 14:28:09 +0000[diff] [blame]214<li><a href="http://llvm.cs.uiuc.edu/PR337">[livevar] Live variables missed physical register use of aliased definition</a></li>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]215</ol>
216
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]217<p>Bugs in the C/C++ front-end:</p>
218
219<ol>
Chris Lattner3553fe32004-05-07 18:40:38 +0000[diff] [blame]220<li><a href="http://llvm.cs.uiuc.edu/PR326">[llvmgcc] Crash on use of undeclared enum type</a></li>
221<li><a href="http://llvm.cs.uiuc.edu/PR298">[llvmgcc] Variable length array indexing miscompiled</a></li>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]222</ol>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]223
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]224</div>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]225
226<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]227<div class="doc_section">
228 <a name="portability">Portability and Supported Platforms</a>
229</div>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]230<!-- *********************************************************************** -->
231
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]232<div class="doc_text">
233
Brian Gaekee3e557e2004-05-09 05:28:35 +0000[diff] [blame]234<p>LLVM has been extensively tested on Intel and AMD machines running Red Hat
235Linux. It has also been tested under FreeBSD, and on Sun UltraSPARC
236workstations running Solaris 8. Additionally, LLVM works on Mac OS X 10.3 and
237above, but only with the C backend and interpreter; no native machine-code
238generator for the PowerPC is available yet.</p>
239
240<p>The core LLVM infrastructure uses
241<a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself
242to the machine and operating system on which it is built. However, minor
243porting may be required to get LLVM to work on new platforms. We welcome your
244portability patches and reports of successful builds or error messages.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]245
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]246</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]247
Brian Gaeke86a6c752004-04-20 18:18:46 +0000[diff] [blame]248<!--=========================================================================-->
249<div class="doc_subsection">
250In this release, the following portability problems were fixed:
251</div>
252
253<ol>
254<li><a href="http://llvm.cs.uiuc.edu/PR304">warnings compiling Stacker compiler on Mac OS X</a></li>
Chris Lattnerea309ff2004-05-04 17:04:09 +0000[diff] [blame]255<li><a href="http://llvm.cs.uiuc.edu/PR308">Archive file reader doesn't understand abbreviated names in headers</a></li>
Brian Gaeke86a6c752004-04-20 18:18:46 +0000[diff] [blame]256</ol>
257
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]258<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]259<div class="doc_section">
260 <a name="knownproblems">Known Problems</a>
261</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]262<!-- *********************************************************************** -->
263
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]264<div class="doc_text">
265
266<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]267component. As new problems are discovered, they will be added to these
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]268sections. If you run into a problem, please check the <a
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]269href="http://llvm.cs.uiuc.edu/bugs/">LLVM bug database</a> and submit a bug if
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]270there isn't already one.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]271
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]272</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]273
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]274<!-- ======================================================================= -->
275<div class="doc_subsection">
276 <a name="experimental">Experimental features included with this release</a>
277</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]278
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]279<div class="doc_text">
280
281<p>
282The following components of this LLVM release are either untested, known to be
283broken or unreliable, or are in early development. These components should not
284be relied on, and bugs should not be filed against them, but they may be useful
285to some people. In particular, if you would like to work on one of these
286components, please contact us on the llvmdev list.
287</p>
288
289<ul>
290<li>The following passes are incomplete or buggy: <tt>-pgmdep, -memdep,
291 -ipmodref, -sortstructs, -swapstructs, -cee</tt></li>
292
293<li>The <tt>-pre</tt> pass is incomplete (there are cases it doesn't handle that
294 it should) and not thoroughly tested.</li>
295<li>The <tt>llvm-ar</tt> tool is incomplete and probably buggy.</li>
296<li>The <tt>llvm-db</tt> tool is in a very early stage of development.</li>
297</ul>
298
299</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]300
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]301<!-- ======================================================================= -->
302<div class="doc_subsection">
303 <a name="core">Known problems with the LLVM Core</a>
304</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]305
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]306<div class="doc_text">
307
308<ul>
309
310<li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not
311work.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]312
313<li>The JIT does not use mutexes to protect its internal data structures. As
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]314such, execution of a threaded program could cause these data structures to be
315corrupted.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]316
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]317<li>It is not possible to <tt>dlopen</tt> an LLVM bytecode file in the JIT.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]318
Chris Lattnera623e482003-10-20 19:05:03 +0000[diff] [blame]319<li>Linking in static archive files (.a files) is very slow (there is no symbol
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]320table in the archive).</li>
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]321
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]322<li>The gccld program <a href="http://llvm.cs.uiuc.edu/PR139">does not link
323objects/archives in the order specified on the command line.</a></li>
Chris Lattneraebc66a2004-02-15 23:09:07 +0000[diff] [blame]324
325<li><a href="http://llvm.cs.uiuc.edu/PR240">The lower-invoke pass does not mark
John Criswell5d6345a2004-03-12 21:29:42 +0000[diff] [blame]326values live across a setjmp as volatile</a>. This missing feature only affects
Chris Lattneraebc66a2004-02-15 23:09:07 +0000[diff] [blame]327targets whose setjmp/longjmp libraries do not save and restore the entire
328register file.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]329</ul>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]330</div>
331
332<!-- ======================================================================= -->
333<div class="doc_subsection">
334 <a name="c-fe">Known problems with the C front-end</a>
335</div>
Chris Lattner178f3db2003-10-02 05:07:23 +0000[diff] [blame]336
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]337<!-- _______________________________________________________________________ -->
Chris Lattner5a8a7282003-12-14 05:03:43 +0000[diff] [blame]338<div class="doc_subsubsection">Bugs</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]339
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]340<div class="doc_text">
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]341<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]342<li>C99 Variable sized arrays do not release stack memory when they go out of
343 scope. Thus, the following program may run out of stack space:
344<pre>
345 for (i = 0; i != 1000000; ++i) {
346 int X[n];
347 foo(X);
348 }
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]349</pre></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]350
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]351<li>
352Initialization of global union variables can only be done
353<a href="http://llvm.cs.uiuc.edu/bugs/show_bug.cgi?id=162">with the largest
354union member</a>.
355</li>
Chris Lattner1ab58dd2004-03-16 21:39:04 +0000[diff] [blame]356
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]357<li><a href="http://llvm.cs.uiuc.edu/PR244">[llvm-gcc] Error when an implicitly
358external function is re-declared as static</a></li>
Chris Lattner1ab58dd2004-03-16 21:39:04 +0000[diff] [blame]359
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]360</ul>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]361</div>
362
363<!-- _______________________________________________________________________ -->
364<div class="doc_subsubsection">
365 Notes
366</div>
367
368<div class="doc_text">
369
370<ul>
371
372<li>Inline assembly is not yet supported.</li>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]373
374<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]375support for floating point data types of any size other than 32 and 64
376bits.</li>
377
378<li>The following Unix system functionality has not been tested and may not
379work:
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]380 <ol>
381 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
382 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
383 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
384 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
385 - These functions have not been tested.
386 </ol></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]387
388<li>Although many GCC extensions are supported, some are not. In particular,
389 the following extensions are known to <b>not be</b> supported:
390 <ol>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]391 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Local-Labels.html#Local%20Labels">Local Labels</a>: Labels local to a block.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]392 <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>
393 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
394 <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 Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]395 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constraints.html#Constraints">Constraints</a>: Constraints for asm operands.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]396 <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>
397 <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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]398 <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>
399 <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>
400 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables.</li>
401 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Pragmas.html#Pragmas">Pragmas</a>: Pragmas accepted by GCC.</li>
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]402 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]403
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]404 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]405 attribute means that the LLVM compiler ignores the presence of the attribute,
406 but the code should still work. An unsupported attribute is one which is
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]407 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]408 the program.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]409
410 <ol>
411 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
412 Arrays whose length is computed at run time.<br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]413 Supported, but allocated stack space is not freed until the function returns (noted above).</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]414
415 <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]416
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]417 Declaring that functions have no side effects or that they can never
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]418 return.<br>
419
420 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
421 <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>,
422 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
423
424 <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>,
425 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
426 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
427
428 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
429 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
430 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]431
432 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
433 Specifying attributes of variables.<br>
434 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
435 <tt>deprecated</tt>, <tt>transparent_union</tt>,
436 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]437
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]438 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
439 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
440 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]441 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]442
Misha Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]443 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Type-Attributes.html#Type%20Attributes">Type Attributes</a>: Specifying attributes of types.<br>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]444 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]445 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]446
447 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
448 all target specific attributes.</li>
449
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]450 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
451 Other built-in functions.<br>
452 We support all builtins which have a C language equivalent (e.g.,
453 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
454 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]455 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt> (ignored).</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]456
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]457 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]458
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]459 <p>The following extensions <b>are</b> known to be supported:</p>
460
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]461 <ol>
Chris Lattnerd3dc8502004-03-16 08:54:07 +0000[diff] [blame]462 <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]463 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
464 <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>
465 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Lvalues.html#Lvalues">Lvalues</a>: Using <code>?:</code>, "<code>,</code>" and casts in lvalues.</li>
466 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
467 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
468 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
469 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
470 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
471 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
472 <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>
473 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
474 <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]475 <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]476 <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]477 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
478or arrays as values.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]479 <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]480 <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]481 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
482 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
483 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li>
484 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C---Comments.html#C++%20Comments">C++ Comments</a>: C++ comments are recognized.</li>
485 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
486 <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>
487 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
488 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
489 <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>
490 <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>
491 <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]492 <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]493 <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>
494 <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]495 </ol></li>
496
497</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]498
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]499<p>If you run into GCC extensions which have not been included in any of these
500lists, please let us know (also including whether or not they work).</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]501
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]502</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]503
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]504<!-- ======================================================================= -->
505<div class="doc_subsection">
506 <a name="c++-fe">Known problems with the C++ front-end</a>
507</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]508
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]509<div class="doc_text">
510
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]511<p>For this release, the C++ front-end is considered to be fully functional but
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame]512has not been tested as thoroughly as the C front-end. It has been tested and
513works for a number of non-trivial programs, but there may be lurking bugs.
514Please report any bugs or problems.</p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]515
516</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]517
518<!-- _______________________________________________________________________ -->
Chris Lattner141ebb62004-02-14 04:12:41 +0000[diff] [blame]519<div class="doc_subsubsection">Bugs</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]520
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]521<div class="doc_text">
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]522
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]523<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]524<li>The C++ front-end inherits all problems afflicting the <a href="#c-fe">C
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]525 front-end</a>.</li>
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]526</ul>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]527</div>
528
529<!-- _______________________________________________________________________ -->
530<div class="doc_subsubsection">
531 Notes
532</div>
533
534<div class="doc_text">
535
536<ul>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]537
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]538<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
539parser is significantly more standards compliant (and picky) than prior GCC
540versions. For more information, see the C++ section of the <a
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame]541href="http://gcc.gnu.org/gcc-3.4/changes.html">GCC 3.4 release notes</a>.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]542
543<li>Destructors for local objects are not always run when a <tt>longjmp</tt> is
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]544 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]545 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]546 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]547 better than most compilers).</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]548
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]549<li>The LLVM C++ front-end follows the <a
550 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
551 This document, which is not Itanium specific, specifies a standard for name
552 mangling, class layout, v-table layout, RTTI formats, and other C++
553 representation issues. Because we use this API, code generated by the LLVM
554 compilers should be binary compatible with machine code generated by other
555 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
556 <i>However</i>, the exception handling mechanism used by LLVM is very
557 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]558 interact correctly</b>. </li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]559
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]560</ul>
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]561
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]562</div>
563
564<!-- ======================================================================= -->
565<div class="doc_subsection">
566 <a name="x86-be">Known problems with the X86 back-end</a>
567</div>
568
569<div class="doc_text">
570
571<ul>
Chris Lattnerc5b7b242004-02-08 22:23:33 +0000[diff] [blame]572<li>None so far.
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]573</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]574
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]575</div>
576
577<!-- ======================================================================= -->
578<div class="doc_subsection">
579 <a name="sparc-be">Known problems with the Sparc back-end</a>
580</div>
581
582<div class="doc_text">
583
584<ul>
Chris Lattner9e0b81c2004-03-19 19:22:28 +0000[diff] [blame]585<li>There are several programs in the LLVM testsuite that the Sparc code generator is known to miscompile.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]586</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]587
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]588</div>
589
590<!-- ======================================================================= -->
591<div class="doc_subsection">
592 <a name="c-be">Known problems with the C back-end</a>
593</div>
594
595<div class="doc_text">
596
597<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]598
599<li>The C back-end produces code that violates the ANSI C Type-Based Alias
600Analysis rules. As such, special options may be necessary to compile the code
601(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]602problem probably cannot be fixed.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]603
Chris Lattnera623e482003-10-20 19:05:03 +0000[diff] [blame]604<li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]605cannot include special floating point numbers like Not-A-Number or
606Infinity.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]607
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]608<li><a href="http://llvm.cs.uiuc.edu/PR56">Zero arg vararg functions are not
Chris Lattnerb28c3282003-10-24 04:03:19 +0000[diff] [blame]609supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]610frontends.</li>
Chris Lattnerb28c3282003-10-24 04:03:19 +0000[diff] [blame]611
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]612</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]613
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]614</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]615
616<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]617<div class="doc_section">
618 <a name="additionalinfo">Additional Information</a>
619</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]620<!-- *********************************************************************** -->
621
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]622<div class="doc_text">
623
624<p>A wide variety of additional information is available on the LLVM web page,
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]625including mailing lists and publications describing algorithms and components
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]626implemented in LLVM. The web page also contains versions of the API
627documentation which is up-to-date with the CVS version of the source code. You
628can access versions of these documents specific to this release by going into
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]629the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]630
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]631<p>If you have any questions or comments about LLVM, please feel free to contact
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]632us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing
633lists</a>.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]634
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]635</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]636
637<!-- *********************************************************************** -->
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]638
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]639<hr>
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]640<address>
Misha Brukman8834af92003-12-21 22:53:21 +0000[diff] [blame]641 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
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643 <a href="http://validator.w3.org/check/referer"><img
644 src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a>
645
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]646 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]647 Last modified: $Date$
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]648</address>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]649
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]650</body>
651</html>