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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 Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]214</ol>
215
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]216<p>Bugs in the C/C++ front-end:</p>
217
218<ol>
Chris Lattner3553fe32004-05-07 18:40:38 +0000[diff] [blame]219<li><a href="http://llvm.cs.uiuc.edu/PR326">[llvmgcc] Crash on use of undeclared enum type</a></li>
220<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]221</ol>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]222
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]223</div>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]224
225<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]226<div class="doc_section">
227 <a name="portability">Portability and Supported Platforms</a>
228</div>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]229<!-- *********************************************************************** -->
230
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]231<div class="doc_text">
232
Brian Gaekee3e557e2004-05-09 05:28:35 +0000[diff] [blame]233<p>LLVM has been extensively tested on Intel and AMD machines running Red Hat
234Linux. It has also been tested under FreeBSD, and on Sun UltraSPARC
235workstations running Solaris 8. Additionally, LLVM works on Mac OS X 10.3 and
236above, but only with the C backend and interpreter; no native machine-code
237generator for the PowerPC is available yet.</p>
238
239<p>The core LLVM infrastructure uses
240<a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself
241to the machine and operating system on which it is built. However, minor
242porting may be required to get LLVM to work on new platforms. We welcome your
243portability patches and reports of successful builds or error messages.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]244
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]245</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]246
Brian Gaeke86a6c752004-04-20 18:18:46 +0000[diff] [blame]247<!--=========================================================================-->
248<div class="doc_subsection">
249In this release, the following portability problems were fixed:
250</div>
251
252<ol>
253<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]254<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]255</ol>
256
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]257<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]258<div class="doc_section">
259 <a name="knownproblems">Known Problems</a>
260</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]261<!-- *********************************************************************** -->
262
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]263<div class="doc_text">
264
265<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]266component. As new problems are discovered, they will be added to these
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]267sections. If you run into a problem, please check the <a
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]268href="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]269there isn't already one.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]270
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]271</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]272
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]273<!-- ======================================================================= -->
274<div class="doc_subsection">
275 <a name="experimental">Experimental features included with this release</a>
276</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]277
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]278<div class="doc_text">
279
280<p>
281The following components of this LLVM release are either untested, known to be
282broken or unreliable, or are in early development. These components should not
283be relied on, and bugs should not be filed against them, but they may be useful
284to some people. In particular, if you would like to work on one of these
285components, please contact us on the llvmdev list.
286</p>
287
288<ul>
289<li>The following passes are incomplete or buggy: <tt>-pgmdep, -memdep,
290 -ipmodref, -sortstructs, -swapstructs, -cee</tt></li>
291
292<li>The <tt>-pre</tt> pass is incomplete (there are cases it doesn't handle that
293 it should) and not thoroughly tested.</li>
294<li>The <tt>llvm-ar</tt> tool is incomplete and probably buggy.</li>
295<li>The <tt>llvm-db</tt> tool is in a very early stage of development.</li>
296</ul>
297
298</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]299
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]300<!-- ======================================================================= -->
301<div class="doc_subsection">
302 <a name="core">Known problems with the LLVM Core</a>
303</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]304
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]305<div class="doc_text">
306
307<ul>
308
309<li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not
310work.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]311
312<li>The JIT does not use mutexes to protect its internal data structures. As
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]313such, execution of a threaded program could cause these data structures to be
314corrupted.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]315
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]316<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]317
Chris Lattnera623e482003-10-20 19:05:03 +0000[diff] [blame]318<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]319table in the archive).</li>
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]320
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]321<li>The gccld program <a href="http://llvm.cs.uiuc.edu/PR139">does not link
322objects/archives in the order specified on the command line.</a></li>
Chris Lattneraebc66a2004-02-15 23:09:07 +0000[diff] [blame]323
324<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]325values live across a setjmp as volatile</a>. This missing feature only affects
Chris Lattneraebc66a2004-02-15 23:09:07 +0000[diff] [blame]326targets whose setjmp/longjmp libraries do not save and restore the entire
327register file.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]328</ul>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]329</div>
330
331<!-- ======================================================================= -->
332<div class="doc_subsection">
333 <a name="c-fe">Known problems with the C front-end</a>
334</div>
Chris Lattner178f3db2003-10-02 05:07:23 +0000[diff] [blame]335
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]336<!-- _______________________________________________________________________ -->
Chris Lattner5a8a7282003-12-14 05:03:43 +0000[diff] [blame]337<div class="doc_subsubsection">Bugs</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]338
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]339<div class="doc_text">
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]340<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]341<li>C99 Variable sized arrays do not release stack memory when they go out of
342 scope. Thus, the following program may run out of stack space:
343<pre>
344 for (i = 0; i != 1000000; ++i) {
345 int X[n];
346 foo(X);
347 }
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]348</pre></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]349
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]350<li>
351Initialization of global union variables can only be done
352<a href="http://llvm.cs.uiuc.edu/bugs/show_bug.cgi?id=162">with the largest
353union member</a>.
354</li>
Chris Lattner1ab58dd2004-03-16 21:39:04 +0000[diff] [blame]355
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]356<li><a href="http://llvm.cs.uiuc.edu/PR244">[llvm-gcc] Error when an implicitly
357external function is re-declared as static</a></li>
Chris Lattner1ab58dd2004-03-16 21:39:04 +0000[diff] [blame]358
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]359</ul>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]360</div>
361
362<!-- _______________________________________________________________________ -->
363<div class="doc_subsubsection">
364 Notes
365</div>
366
367<div class="doc_text">
368
369<ul>
370
371<li>Inline assembly is not yet supported.</li>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]372
373<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]374support for floating point data types of any size other than 32 and 64
375bits.</li>
376
377<li>The following Unix system functionality has not been tested and may not
378work:
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]379 <ol>
380 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
381 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
382 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
383 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
384 - These functions have not been tested.
385 </ol></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]386
387<li>Although many GCC extensions are supported, some are not. In particular,
388 the following extensions are known to <b>not be</b> supported:
389 <ol>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]390 <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]391 <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>
392 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
393 <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]394 <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]395 <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>
396 <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]397 <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>
398 <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>
399 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables.</li>
400 <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]401 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]402
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]403 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]404 attribute means that the LLVM compiler ignores the presence of the attribute,
405 but the code should still work. An unsupported attribute is one which is
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]406 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]407 the program.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]408
409 <ol>
410 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
411 Arrays whose length is computed at run time.<br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]412 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]413
414 <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]415
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]416 Declaring that functions have no side effects or that they can never
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]417 return.<br>
418
419 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
420 <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>,
421 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
422
423 <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>,
424 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
425 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
426
427 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
428 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
429 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]430
431 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
432 Specifying attributes of variables.<br>
433 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
434 <tt>deprecated</tt>, <tt>transparent_union</tt>,
435 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]436
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]437 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
438 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
439 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]440 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]441
Misha Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]442 <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]443 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]444 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]445
446 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
447 all target specific attributes.</li>
448
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]449 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
450 Other built-in functions.<br>
451 We support all builtins which have a C language equivalent (e.g.,
452 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
453 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]454 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt> (ignored).</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]455
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]456 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]457
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]458 <p>The following extensions <b>are</b> known to be supported:</p>
459
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]460 <ol>
Chris Lattnerd3dc8502004-03-16 08:54:07 +0000[diff] [blame]461 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Labels-as-Values.html#Labels%20as%20Values">Labels as Values</a>: Getting pointers to labels and computed gotos.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]462 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
463 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Typeof.html#Typeof">Typeof</a>: <code>typeof</code>: referring to the type of an expression.</li>
464 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Lvalues.html#Lvalues">Lvalues</a>: Using <code>?:</code>, "<code>,</code>" and casts in lvalues.</li>
465 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
466 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
467 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
468 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
469 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
470 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
471 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variadic-Macros.html#Variadic%20Macros">Variadic Macros</a>: Macros with a variable number of arguments.</li>
472 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
473 <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]474 <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]475 <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]476 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
477or arrays as values.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]478 <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]479 <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]480 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
481 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
482 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li>
483 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C---Comments.html#C++%20Comments">C++ Comments</a>: C++ comments are recognized.</li>
484 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
485 <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>
486 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
487 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
488 <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>
489 <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>
490 <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]491 <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]492 <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>
493 <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]494 </ol></li>
495
496</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]497
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]498<p>If you run into GCC extensions which have not been included in any of these
499lists, please let us know (also including whether or not they work).</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]500
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]501</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]502
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]503<!-- ======================================================================= -->
504<div class="doc_subsection">
505 <a name="c++-fe">Known problems with the C++ front-end</a>
506</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]507
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]508<div class="doc_text">
509
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]510<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]511has not been tested as thoroughly as the C front-end. It has been tested and
512works for a number of non-trivial programs, but there may be lurking bugs.
513Please report any bugs or problems.</p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]514
515</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]516
517<!-- _______________________________________________________________________ -->
Chris Lattner141ebb62004-02-14 04:12:41 +0000[diff] [blame]518<div class="doc_subsubsection">Bugs</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]519
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]520<div class="doc_text">
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]521
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]522<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]523<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]524 front-end</a>.</li>
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]525</ul>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]526</div>
527
528<!-- _______________________________________________________________________ -->
529<div class="doc_subsubsection">
530 Notes
531</div>
532
533<div class="doc_text">
534
535<ul>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]536
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]537<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
538parser is significantly more standards compliant (and picky) than prior GCC
539versions. For more information, see the C++ section of the <a
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame]540href="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]541
542<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]543 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]544 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]545 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]546 better than most compilers).</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]547
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]548<li>The LLVM C++ front-end follows the <a
549 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
550 This document, which is not Itanium specific, specifies a standard for name
551 mangling, class layout, v-table layout, RTTI formats, and other C++
552 representation issues. Because we use this API, code generated by the LLVM
553 compilers should be binary compatible with machine code generated by other
554 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
555 <i>However</i>, the exception handling mechanism used by LLVM is very
556 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]557 interact correctly</b>. </li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]558
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]559</ul>
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]560
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]561</div>
562
563<!-- ======================================================================= -->
564<div class="doc_subsection">
565 <a name="x86-be">Known problems with the X86 back-end</a>
566</div>
567
568<div class="doc_text">
569
570<ul>
Chris Lattnerc5b7b242004-02-08 22:23:33 +0000[diff] [blame]571<li>None so far.
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]572</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]573
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]574</div>
575
576<!-- ======================================================================= -->
577<div class="doc_subsection">
578 <a name="sparc-be">Known problems with the Sparc back-end</a>
579</div>
580
581<div class="doc_text">
582
583<ul>
Chris Lattner9e0b81c2004-03-19 19:22:28 +0000[diff] [blame]584<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]585</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]586
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]587</div>
588
589<!-- ======================================================================= -->
590<div class="doc_subsection">
591 <a name="c-be">Known problems with the C back-end</a>
592</div>
593
594<div class="doc_text">
595
596<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]597
598<li>The C back-end produces code that violates the ANSI C Type-Based Alias
599Analysis rules. As such, special options may be necessary to compile the code
600(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]601problem probably cannot be fixed.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]602
Chris Lattnera623e482003-10-20 19:05:03 +0000[diff] [blame]603<li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]604cannot include special floating point numbers like Not-A-Number or
605Infinity.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]606
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]607<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]608supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]609frontends.</li>
Chris Lattnerb28c3282003-10-24 04:03:19 +0000[diff] [blame]610
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]611</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]612
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]613</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]614
615<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]616<div class="doc_section">
617 <a name="additionalinfo">Additional Information</a>
618</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]619<!-- *********************************************************************** -->
620
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]621<div class="doc_text">
622
623<p>A wide variety of additional information is available on the LLVM web page,
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]624including mailing lists and publications describing algorithms and components
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]625implemented in LLVM. The web page also contains versions of the API
626documentation which is up-to-date with the CVS version of the source code. You
627can access versions of these documents specific to this release by going into
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]628the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]629
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]630<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]631us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing
632lists</a>.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]633
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]634</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]635
636<!-- *********************************************************************** -->
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]637
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]638<hr>
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]639<address>
Misha Brukman8834af92003-12-21 22:53:21 +0000[diff] [blame]640 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
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644
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]645 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]646 Last modified: $Date$
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]647</address>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]648
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]649</body>
650</html>