blob: 499f9a6deb18b1f0d5022dd53fe6e2de7d2cf32a [file] [log] [blame]
Misha Brukman500bc302003-11-22 00:38:41 +00001<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
2 "http://www.w3.org/TR/html4/strict.dtd">
3<html>
4<head>
Reid Spencer6454ed32004-11-18 18:38:58 +00005 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
Misha Brukman500bc302003-11-22 00:38:41 +00006 <link rel="stylesheet" href="llvm.css" type="text/css">
Jeffrey Yasskinbec48772010-01-28 01:14:43 +00007 <title>LLVM 2.7 Release Notes</title>
Misha Brukman500bc302003-11-22 00:38:41 +00008</head>
9<body>
Chris Lattner79c3fe12003-10-02 04:57:28 +000010
Jeffrey Yasskinbec48772010-01-28 01:14:43 +000011<div class="doc_title">LLVM 2.7 Release Notes</div>
Mikhail Glushenkovea65d7d2008-10-13 02:08:34 +000012
Chris Lattner0e464a92010-03-17 04:02:39 +000013<img align=right src="http://llvm.org/img/DragonSmall.png"
14 width="136" height="136">
15
Chris Lattner79c3fe12003-10-02 04:57:28 +000016<ol>
Misha Brukman500bc302003-11-22 00:38:41 +000017 <li><a href="#intro">Introduction</a></li>
Chris Lattner96a445e2008-10-13 18:01:01 +000018 <li><a href="#subproj">Sub-project Status Update</a></li>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +000019 <li><a href="#externalproj">External Projects Using LLVM 2.7</a></li>
20 <li><a href="#whatsnew">What's New in LLVM 2.7?</a></li>
Chris Lattner4b538b92004-04-30 22:17:12 +000021 <li><a href="GettingStarted.html">Installation Instructions</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +000022 <li><a href="#portability">Portability and Supported Platforms</a></li>
Dan Gohman44aa9212008-10-14 16:23:02 +000023 <li><a href="#knownproblems">Known Problems</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +000024 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +000025</ol>
26
Chris Lattner7911ce22004-05-23 21:07:27 +000027<div class="doc_author">
Dan Gohman44aa9212008-10-14 16:23:02 +000028 <p>Written by the <a href="http://llvm.org">LLVM Team</a></p>
Misha Brukman500bc302003-11-22 00:38:41 +000029</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +000030
Jeffrey Yasskinbec48772010-01-28 01:14:43 +000031<h1 style="color:red">These are in-progress notes for the upcoming LLVM 2.7
32release.<br>
33You may prefer the
34<a href="http://llvm.org/releases/2.6/docs/ReleaseNotes.html">LLVM 2.6
35Release Notes</a>.</h1>
36
Chris Lattner79c3fe12003-10-02 04:57:28 +000037<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +000038<div class="doc_section">
39 <a name="intro">Introduction</a>
40</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +000041<!-- *********************************************************************** -->
42
Misha Brukman500bc302003-11-22 00:38:41 +000043<div class="doc_text">
44
Chris Lattnerf6662f92008-10-13 17:57:36 +000045<p>This document contains the release notes for the LLVM Compiler
Jeffrey Yasskinbec48772010-01-28 01:14:43 +000046Infrastructure, release 2.7. Here we describe the status of LLVM, including
Chris Lattnerf6662f92008-10-13 17:57:36 +000047major improvements from the previous release and significant known problems.
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +000048All LLVM releases may be downloaded from the <a
Chris Lattnerf6662f92008-10-13 17:57:36 +000049href="http://llvm.org/releases/">LLVM releases web site</a>.</p>
Chris Lattner19092612003-10-02 16:38:05 +000050
Chris Lattner7506b1d2004-12-07 08:04:13 +000051<p>For more information about LLVM, including information about the latest
Chris Lattnerc463b272005-10-29 07:07:09 +000052release, please check out the <a href="http://llvm.org/">main LLVM
Chris Lattner47ad72c2003-10-07 21:38:31 +000053web site</a>. If you have questions or comments, the <a
Chris Lattnerc66bfef2010-03-17 04:41:49 +000054href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM Developer's
55Mailing List</a> is a good place to send them.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +000056
Mikhail Glushenkovea65d7d2008-10-13 02:08:34 +000057<p>Note that if you are reading this file from a Subversion checkout or the
Chris Lattner84977642007-09-21 03:54:09 +000058main LLVM web page, this document applies to the <i>next</i> release, not the
Gabor Greiffa933f82008-10-14 11:00:32 +000059current one. To see the release notes for a specific release, please see the
Chris Lattner84977642007-09-21 03:54:09 +000060<a href="http://llvm.org/releases/">releases page</a>.</p>
Misha Brukman500bc302003-11-22 00:38:41 +000061
Chris Lattnerc66bfef2010-03-17 04:41:49 +000062
Chris Lattnerdc910082010-03-17 06:41:58 +000063<p>FIXME: llvm.org moved to new server, mention new logo, Ted and Doug new code
64 owners.</p>
Chris Lattnerc66bfef2010-03-17 04:41:49 +000065
Misha Brukman500bc302003-11-22 00:38:41 +000066</div>
Chris Lattner61358ab2009-10-13 17:48:04 +000067
Chris Lattner79c3fe12003-10-02 04:57:28 +000068
Chris Lattner61358ab2009-10-13 17:48:04 +000069<!--
70Almost dead code.
71 include/llvm/Analysis/LiveValues.h => Dan
72 lib/Transforms/IPO/MergeFunctions.cpp => consider for 2.8.
73 llvm/Analysis/PointerTracking.h => Edwin wants this, consider for 2.8.
Chris Lattner76ef2982010-01-09 22:30:40 +000074 ABCD, SCCVN, GEPSplitterPass
Chris Lattner048fe3c2010-01-16 21:25:13 +000075 MSIL backend?
Chris Lattnerdc910082010-03-17 06:41:58 +000076 lib/Transforms/Utils/SSI.cpp -> ABCD depends on it.
Chris Lattner61358ab2009-10-13 17:48:04 +000077-->
78
79
Jeffrey Yasskinbec48772010-01-28 01:14:43 +000080<!-- Features that need text if they're finished for 2.7:
Chris Lattner61358ab2009-10-13 17:48:04 +000081 gcc plugin.
82 strong phi elim
83 variable debug info for optimized code
Chris Lattnerab68e9e2009-02-26 22:33:38 +000084 postalloc scheduler: anti dependence breaking, hazard recognizer?
Chris Lattner61358ab2009-10-13 17:48:04 +000085 metadata
86 loop dependence analysis
87 ELF Writer? How stable?
88 <li>PostRA scheduler improvements, ARM adoption (David Goodwin).</li>
Chris Lattneracce85d2008-02-10 07:46:44 +000089 -->
Mikhail Glushenkovea65d7d2008-10-13 02:08:34 +000090
Chris Lattner547a3912008-10-12 19:47:48 +000091 <!-- for announcement email:
Chris Lattner61358ab2009-10-13 17:48:04 +000092 Logo web page.
93 llvm devmtg
94 compiler_rt
95 KLEE web page at klee.llvm.org
96 Many new papers added to /pubs/
Chris Lattnerdc910082010-03-17 06:41:58 +000097 Mention gcc plugin.
Chris Lattner74c80df2009-02-25 06:34:50 +000098 -->
Chris Lattneracce85d2008-02-10 07:46:44 +000099
Chris Lattner96a445e2008-10-13 18:01:01 +0000100<!-- *********************************************************************** -->
101<div class="doc_section">
102 <a name="subproj">Sub-project Status Update</a>
Chris Lattnerea34f642008-06-08 21:34:41 +0000103</div>
Chris Lattner96a445e2008-10-13 18:01:01 +0000104<!-- *********************************************************************** -->
Chris Lattnerea34f642008-06-08 21:34:41 +0000105
106<div class="doc_text">
Chris Lattner8348b472008-06-08 21:58:17 +0000107<p>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000108The LLVM 2.7 distribution currently consists of code from the core LLVM
Chris Lattner61358ab2009-10-13 17:48:04 +0000109repository (which roughly includes the LLVM optimizers, code generators
110and supporting tools), the Clang repository and the llvm-gcc repository. In
111addition to this code, the LLVM Project includes other sub-projects that are in
112development. Here we include updates on these subprojects.
Bill Wendling63d8c552009-03-02 04:28:57 +0000113</p>
Chris Lattner96a445e2008-10-13 18:01:01 +0000114
Chris Lattner8348b472008-06-08 21:58:17 +0000115</div>
116
Chris Lattner96a445e2008-10-13 18:01:01 +0000117
Chris Lattner8348b472008-06-08 21:58:17 +0000118<!--=========================================================================-->
Chris Lattner96a445e2008-10-13 18:01:01 +0000119<div class="doc_subsection">
Chris Lattnerfb97b2d2008-10-13 18:11:54 +0000120<a name="clang">Clang: C/C++/Objective-C Frontend Toolkit</a>
Chris Lattner8348b472008-06-08 21:58:17 +0000121</div>
122
123<div class="doc_text">
124
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000125<p>The <a href="http://clang.llvm.org/">Clang project</a> is ...</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000126
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000127<p>In the LLVM 2.7 time-frame, the Clang team has made many improvements:</p>
Bill Wendling741748a2008-10-27 09:27:33 +0000128
Daniel Dunbar13739432008-10-14 23:25:09 +0000129<ul>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000130<li>...</li>
Chris Lattnerdc910082010-03-17 06:41:58 +0000131include a link to cxx_compatibility.html
Bill Wendling6bc15282009-03-02 04:28:18 +0000132</ul>
Chris Lattnerfb97b2d2008-10-13 18:11:54 +0000133</div>
134
135<!--=========================================================================-->
136<div class="doc_subsection">
137<a name="clangsa">Clang Static Analyzer</a>
138</div>
139
140<div class="doc_text">
141
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000142<p>Previously announced in the 2.4, 2.5, and 2.6 LLVM releases, the Clang project also
Ted Kremenek8b3894c2009-02-27 07:01:32 +0000143includes an early stage static source code analysis tool for <a
144href="http://clang.llvm.org/StaticAnalysis.html">automatically finding bugs</a>
Chris Lattner61358ab2009-10-13 17:48:04 +0000145in C and Objective-C programs. The tool performs checks to find
Ted Kremenek8b3894c2009-02-27 07:01:32 +0000146bugs that occur on a specific path within a program.</p>
Chris Lattnercc042612008-10-14 00:52:49 +0000147
Chris Lattner0e464a92010-03-17 04:02:39 +0000148<p>In the LLVM 2.7 time-frame, the analyzer core has sprouted legs and...</p>
Chris Lattner8348b472008-06-08 21:58:17 +0000149
150</div>
151
Chris Lattner96a445e2008-10-13 18:01:01 +0000152<!--=========================================================================-->
153<div class="doc_subsection">
Nicolas Geoffray99a4d302008-10-14 19:23:04 +0000154<a name="vmkit">VMKit: JVM/CLI Virtual Machine Implementation</a>
Chris Lattner96a445e2008-10-13 18:01:01 +0000155</div>
156
157<div class="doc_text">
158<p>
Nicolas Geoffray99a4d302008-10-14 19:23:04 +0000159The <a href="http://vmkit.llvm.org/">VMKit project</a> is an implementation of
Chris Lattner61358ab2009-10-13 17:48:04 +0000160a JVM and a CLI Virtual Machine (Microsoft .NET is an
161implementation of the CLI) using LLVM for static and just-in-time
162compilation.</p>
Chris Lattner96a445e2008-10-13 18:01:01 +0000163
Chris Lattner61358ab2009-10-13 17:48:04 +0000164<p>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000165VMKit version ?? builds with LLVM 2.7 and you can find it on its
Chris Lattner61358ab2009-10-13 17:48:04 +0000166<a href="http://vmkit.llvm.org/releases/">web page</a>. The release includes
Nicolas Geoffray56d313d2008-10-15 20:25:04 +0000167bug fixes, cleanup and new features. The major changes are:</p>
Chris Lattner96a445e2008-10-13 18:01:01 +0000168
Nicolas Geoffray99a4d302008-10-14 19:23:04 +0000169<ul>
170
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000171<li>...</li>
Nicolas Geoffray99a4d302008-10-14 19:23:04 +0000172
173</ul>
Chris Lattner96a445e2008-10-13 18:01:01 +0000174</div>
175
Chris Lattner61358ab2009-10-13 17:48:04 +0000176
177<!--=========================================================================-->
178<div class="doc_subsection">
179<a name="compiler-rt">compiler-rt: Compiler Runtime Library</a>
180</div>
181
182<div class="doc_text">
183<p>
184The new LLVM <a href="http://compiler-rt.llvm.org/">compiler-rt project</a>
185is a simple library that provides an implementation of the low-level
186target-specific hooks required by code generation and other runtime components.
187For example, when compiling for a 32-bit target, converting a double to a 64-bit
188unsigned integer is compiled into a runtime call to the "__fixunsdfdi"
189function. The compiler-rt library provides highly optimized implementations of
190this and other low-level routines (some are 3x faster than the equivalent
191libgcc routines).</p>
192
193<p>
194All of the code in the compiler-rt project is available under the standard LLVM
195License, a "BSD-style" license.</p>
196
197</div>
198
199<!--=========================================================================-->
200<div class="doc_subsection">
201<a name="klee">KLEE: Symbolic Execution and Automatic Test Case Generator</a>
202</div>
203
204<div class="doc_text">
205<p>
206The new LLVM <a href="http://klee.llvm.org/">KLEE project</a> is a symbolic
207execution framework for programs in LLVM bitcode form. KLEE tries to
208symbolically evaluate "all" paths through the application and records state
209transitions that lead to fault states. This allows it to construct testcases
210that lead to faults and can even be used to verify algorithms. For more
211details, please see the <a
212href="http://llvm.org/pubs/2008-12-OSDI-KLEE.html">OSDI 2008 paper</a> about
213KLEE.</p>
214
215</div>
216
217<!--=========================================================================-->
218<div class="doc_subsection">
219<a name="dragonegg">DragonEgg: GCC-4.5 as an LLVM frontend</a>
220</div>
221
222<div class="doc_text">
223<p>
224The goal of <a href="http://dragonegg.llvm.org/">DragonEgg</a> is to make
225gcc-4.5 act like llvm-gcc without requiring any gcc modifications whatsoever.
Duncan Sands78a1dcc2009-10-15 08:17:44 +0000226<a href="http://dragonegg.llvm.org/">DragonEgg</a> is a shared library (dragonegg.so)
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000227that is loaded by gcc at runtime. It ...
Chris Lattner61358ab2009-10-13 17:48:04 +0000228</p>
229
230</div>
231
232
233<!--=========================================================================-->
234<div class="doc_subsection">
235<a name="mc">llvm-mc: Machine Code Toolkit</a>
236</div>
237
238<div class="doc_text">
239<p>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000240The LLVM Machine Code (MC) Toolkit project is ...
Chris Lattner61358ab2009-10-13 17:48:04 +0000241</p>
242
243</div>
244
245
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000246<!-- *********************************************************************** -->
247<div class="doc_section">
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000248 <a name="externalproj">External Open Source Projects Using LLVM 2.7</a>
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000249</div>
250<!-- *********************************************************************** -->
251
Chris Lattner61358ab2009-10-13 17:48:04 +0000252<div class="doc_text">
253
254<p>An exciting aspect of LLVM is that it is used as an enabling technology for
255 a lot of other language and tools projects. This section lists some of the
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000256 projects that have already been updated to work with LLVM 2.7.</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000257</div>
258
259
260<!--=========================================================================-->
261<div class="doc_subsection">
262<a name="Rubinius">Rubinius</a>
263</div>
264
265<div class="doc_text">
Chris Lattner0e464a92010-03-17 04:02:39 +0000266Need update.
267<!--
Chris Lattner61358ab2009-10-13 17:48:04 +0000268<p><a href="http://github.com/evanphx/rubinius">Rubinius</a> is an environment
269for running Ruby code which strives to write as much of the core class
270implementation in Ruby as possible. Combined with a bytecode interpreting VM, it
271uses LLVM to optimize and compile ruby code down to machine code. Techniques
272such as type feedback, method inlining, and uncommon traps are all used to
273remove dynamism from ruby execution and increase performance.</p>
274
275<p>Since LLVM 2.5, Rubinius has made several major leaps forward, implementing
276a counter based JIT, type feedback and speculative method inlining.
Chris Lattner0e464a92010-03-17 04:02:39 +0000277-->
Chris Lattner61358ab2009-10-13 17:48:04 +0000278</p>
279
280</div>
281
282<!--=========================================================================-->
283<div class="doc_subsection">
284<a name="macruby">MacRuby</a>
285</div>
286
287<div class="doc_text">
288
289<p>
Chris Lattner0e464a92010-03-17 04:02:39 +0000290Need update.
291<!--
Chris Lattner61358ab2009-10-13 17:48:04 +0000292<a href="http://macruby.org">MacRuby</a> is an implementation of Ruby on top of
293core Mac OS X technologies, such as the Objective-C common runtime and garbage
294collector and the CoreFoundation framework. It is principally developed by
295Apple and aims at enabling the creation of full-fledged Mac OS X applications.
296</p>
297
298<p>
299MacRuby uses LLVM for optimization passes, JIT and AOT compilation of Ruby
300expressions. It also uses zero-cost DWARF exceptions to implement Ruby exception
Chris Lattner0e464a92010-03-17 04:02:39 +0000301handling.--> </p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000302
303</div>
304
305
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000306<!--=========================================================================-->
307<div class="doc_subsection">
308<a name="pure">Pure</a>
309</div>
310
311<div class="doc_text">
312<p>
Chris Lattner917cc712009-03-02 02:37:32 +0000313<a href="http://pure-lang.googlecode.com/">Pure</a>
314is an algebraic/functional programming language based on term rewriting.
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000315Programs are collections of equations which are used to evaluate expressions in
316a symbolic fashion. Pure offers dynamic typing, eager and lazy evaluation,
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000317lexical closures, a hygienic macro system (also based on term rewriting),
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000318built-in list and matrix support (including list and matrix comprehensions) and
319an easy-to-use C interface. The interpreter uses LLVM as a backend to
320 JIT-compile Pure programs to fast native code.</p>
321
Chris Lattner477a1fd2010-03-17 17:25:49 +0000322<p>Pure versions 0.43 and later have been tested and are known to work with
323LLVM 2.7 (and continue to work with older LLVM releases >= 2.5).</p>
324
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000325</div>
326
327
328<!--=========================================================================-->
329<div class="doc_subsection">
330<a name="ldc">LLVM D Compiler</a>
331</div>
332
333<div class="doc_text">
334<p>
Chris Lattner0e464a92010-03-17 04:02:39 +0000335Need update.
336<!--
Chris Lattner917cc712009-03-02 02:37:32 +0000337<a href="http://www.dsource.org/projects/ldc">LDC</a> is an implementation of
338the D Programming Language using the LLVM optimizer and code generator.
Chris Lattner61358ab2009-10-13 17:48:04 +0000339The LDC project works great with the LLVM 2.6 release. General improvements in
John Criswell524a5dd2009-03-02 15:28:15 +0000340this
Chris Lattner917cc712009-03-02 02:37:32 +0000341cycle have included new inline asm constraint handling, better debug info
Chris Lattner61358ab2009-10-13 17:48:04 +0000342support, general bug fixes and better x86-64 support. This has allowed
343some major improvements in LDC, getting it much closer to being as
Chris Lattner0e464a92010-03-17 04:02:39 +0000344fully featured as the original DMD compiler from DigitalMars.-->
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000345</p>
346</div>
347
Chris Lattnerbc31caf2009-02-28 18:58:01 +0000348<!--=========================================================================-->
349<div class="doc_subsection">
350<a name="RoadsendPHP">Roadsend PHP</a>
351</div>
352
353<div class="doc_text">
Chris Lattner61358ab2009-10-13 17:48:04 +0000354<p>
355<a href="http://code.roadsend.com/rphp">Roadsend PHP</a> (rphp) is an open
Chris Lattnercade8222009-03-02 19:07:24 +0000356source implementation of the PHP programming
Chris Lattner61358ab2009-10-13 17:48:04 +0000357language that uses LLVM for its optimizer, JIT and static compiler. This is a
Chris Lattner0e464a92010-03-17 04:02:39 +0000358reimplementation of an earlier project that is now based on LLVM.
Chris Lattner477a1fd2010-03-17 17:25:49 +0000359</p>
Chris Lattnerbc31caf2009-02-28 18:58:01 +0000360</div>
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000361
Chris Lattner61358ab2009-10-13 17:48:04 +0000362<!--=========================================================================-->
363<div class="doc_subsection">
364<a name="UnladenSwallow">Unladen Swallow</a>
365</div>
366
367<div class="doc_text">
368<p>
Chris Lattner0e464a92010-03-17 04:02:39 +0000369Need update.
370<!--
Chris Lattner61358ab2009-10-13 17:48:04 +0000371<a href="http://code.google.com/p/unladen-swallow/">Unladen Swallow</a> is a
372branch of <a href="http://python.org/">Python</a> intended to be fully
373compatible and significantly faster. It uses LLVM's optimization passes and JIT
Chris Lattner0e464a92010-03-17 04:02:39 +0000374compiler.-->
375</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000376</div>
377
378<!--=========================================================================-->
379<div class="doc_subsection">
380<a name="llvm-lua">llvm-lua</a>
381</div>
382
383<div class="doc_text">
384<p>
Chris Lattner0e464a92010-03-17 04:02:39 +0000385Need update.
386<!--
Chris Lattner61358ab2009-10-13 17:48:04 +0000387<a href="http://code.google.com/p/llvm-lua/">LLVM-Lua</a> uses LLVM to add JIT
388and static compiling support to the Lua VM. Lua bytecode is analyzed to
389remove type checks, then LLVM is used to compile the bytecode down to machine
Chris Lattner0e464a92010-03-17 04:02:39 +0000390code.-->
391</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000392</div>
393
394<!--=========================================================================-->
395<div class="doc_subsection">
396<a name="icedtea">IcedTea Java Virtual Machine Implementation</a>
397</div>
398
399<div class="doc_text">
400<p>
Chris Lattner0e464a92010-03-17 04:02:39 +0000401Need update.
402<!--
Chris Lattner61358ab2009-10-13 17:48:04 +0000403<a href="http://icedtea.classpath.org/wiki/Main_Page">IcedTea</a> provides a
404harness to build OpenJDK using only free software build tools and to provide
405replacements for the not-yet free parts of OpenJDK. One of the extensions that
406IcedTea provides is a new JIT compiler named <a
407href="http://icedtea.classpath.org/wiki/ZeroSharkFaq">Shark</a> which uses LLVM
408to provide native code generation without introducing processor-dependent
Chris Lattner0e464a92010-03-17 04:02:39 +0000409code.-->
Chris Lattner61358ab2009-10-13 17:48:04 +0000410</p>
411</div>
412
413
Chris Lattner8348b472008-06-08 21:58:17 +0000414
415<!-- *********************************************************************** -->
416<div class="doc_section">
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000417 <a name="whatsnew">What's New in LLVM 2.7?</a>
Chris Lattner8348b472008-06-08 21:58:17 +0000418</div>
419<!-- *********************************************************************** -->
420
Chris Lattnerf8e0b4e2008-06-08 22:59:35 +0000421<div class="doc_text">
422
Chris Lattner61358ab2009-10-13 17:48:04 +0000423<p>This release includes a huge number of bug fixes, performance tweaks and
Chris Lattnerf6662f92008-10-13 17:57:36 +0000424minor improvements. Some of the major improvements and new features are listed
425in this section.
Chris Lattnerf8e0b4e2008-06-08 22:59:35 +0000426</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000427
Chris Lattnerf8e0b4e2008-06-08 22:59:35 +0000428</div>
429
Chris Lattner8348b472008-06-08 21:58:17 +0000430<!--=========================================================================-->
Chris Lattnerea34f642008-06-08 21:34:41 +0000431<div class="doc_subsection">
Chris Lattner252b83d2008-02-06 18:00:06 +0000432<a name="majorfeatures">Major New Features</a>
433</div>
434
435<div class="doc_text">
436
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000437<p>LLVM 2.7 includes several major new capabilities:</p>
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000438
439<ul>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000440<li>...</li>
Chris Lattner8170c102008-02-10 08:18:42 +0000441</ul>
442
Chris Lattnerc66bfef2010-03-17 04:41:49 +0000443Extensible metadata solid.
444
445Debug info improvements: using metadata instead of llvm.dbg global variables.
446This brings several enhancements including improved compile times.
447
448New instruction selector.
449GHC Haskell ABI/ calling conv support.
450Pre-Alpha support for unions in IR.
451New InlineHint and StackAlignment function attributes
452Code generator MC'ized except for debug info and EH.
453New SCEV AA pass: -scev-aa
454Inliner reuses arrays allocas when inlining multiple callers to reduce stack usage.
455MC encoding and disassembler apis.
456Optimal Edge Profiling?
457Instcombine is now a library, has its own IRBuilder to simplify itself.
458New llvm/Support/Regex.h API. FileCheck now does regex's
Chris Lattnerdc910082010-03-17 06:41:58 +0000459Many subtle pointer invalidation bugs in Callgraph have been fixed and it now uses asserting value handles.
460MC Disassembler (with blog post), MCInstPrinter. Many X86 backend and AsmPrinter simplifications
461Various tools like llc and opt now read either .ll or .bc files as input.
462Malloc and free instructions got removed.
463compiler-rt support for ARM.
464completely llvm-gcc NEON support.
465Can transcode from GAS to intel syntax with "llvm-mc foo.s -output-asm-variant=1"
466JIT debug information with GDB 7.0
Chris Lattnerf04bdc52010-03-17 18:15:52 +0000467New CodeGen Level CSE
Chris Lattnerdc910082010-03-17 06:41:58 +0000468CMake can now run tests, what other improvements?
Chris Lattnerf04bdc52010-03-17 18:15:52 +0000469ARM/Thumb using reg scavenging for stack object address materialization (PEI).
Chris Lattnerdc910082010-03-17 06:41:58 +0000470New SSAUpdater and MachineSSAUpdater classes for unstructured ssa updating,
471 changed jump threading, GVN, etc to use it which simplified them and speed
472 them up.
Chris Lattner15a06112010-03-17 06:42:25 +0000473Combiner-AA improvements, why not on by default?
Chris Lattnerf04bdc52010-03-17 18:15:52 +0000474Pre-regalloc tail duplication
475x86 sibcall optimization
476New LSR with full strength reduction mode
477The most awesome sext / zext optimization pass. ?
478
479
Chris Lattnerc66bfef2010-03-17 04:41:49 +0000480
Chris Lattnerdc910082010-03-17 06:41:58 +0000481CondProp pass removed (functionality merged into jump threading).
Chris Lattnerc66bfef2010-03-17 04:41:49 +0000482AndersAA got removed (from 2.7 or mainline?)
Chris Lattnerdc910082010-03-17 06:41:58 +0000483PredSimplify, LoopVR, GVNPRE got removed.
Chris Lattnerc66bfef2010-03-17 04:41:49 +0000484LLVM command line tools now overwrite their output, before they would only do this with -f.
485DOUT removed, use DEBUG(errs() instead.
486Much stuff converted to use raw_ostream instead of std::ostream.
487TargetAsmInfo renamed to MCAsmInfo
488llvm/ADT/iterator.h gone.
489
Chris Lattnerdc910082010-03-17 06:41:58 +0000490
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000491</div>
492
Chris Lattner84977642007-09-21 03:54:09 +0000493<!--=========================================================================-->
494<div class="doc_subsection">
Chris Lattner917cc712009-03-02 02:37:32 +0000495<a name="coreimprovements">LLVM IR and Core Improvements</a>
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000496</div>
497
498<div class="doc_text">
Chris Lattner61358ab2009-10-13 17:48:04 +0000499<p>LLVM IR has several new features for better support of new targets and that
500expose new optimization opportunities:</p>
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000501
Chris Lattner791f77b2008-06-05 06:25:56 +0000502<ul>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000503<li>...</li>
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000504</ul>
Mikhail Glushenkovea65d7d2008-10-13 02:08:34 +0000505
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000506</div>
507
508<!--=========================================================================-->
509<div class="doc_subsection">
Chris Lattneracce85d2008-02-10 07:46:44 +0000510<a name="optimizer">Optimizer Improvements</a>
511</div>
512
513<div class="doc_text">
514
Chris Lattner61358ab2009-10-13 17:48:04 +0000515<p>In addition to a large array of minor performance tweaks and bug fixes, this
Chris Lattnerf3013872008-10-13 21:50:36 +0000516release includes a few major enhancements and additions to the optimizers:</p>
Chris Lattneracce85d2008-02-10 07:46:44 +0000517
518<ul>
519
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000520<li>...</li>
Chris Lattner917cc712009-03-02 02:37:32 +0000521
Chris Lattner61358ab2009-10-13 17:48:04 +0000522</ul>
Chris Lattner917cc712009-03-02 02:37:32 +0000523
Chris Lattnerf2201912010-03-01 19:29:17 +0000524<p>Also, -anders-aa was removed</p>
525
Chris Lattner61358ab2009-10-13 17:48:04 +0000526</div>
Chris Lattner917cc712009-03-02 02:37:32 +0000527
Chris Lattner917cc712009-03-02 02:37:32 +0000528
Chris Lattner61358ab2009-10-13 17:48:04 +0000529<!--=========================================================================-->
530<div class="doc_subsection">
531<a name="executionengine">Interpreter and JIT Improvements</a>
532</div>
Chris Lattnerf3013872008-10-13 21:50:36 +0000533
Chris Lattner61358ab2009-10-13 17:48:04 +0000534<div class="doc_text">
535
536<ul>
Jeffrey Yasskin01eba392010-01-29 19:10:38 +0000537<li>The JIT now <a
538href="http://llvm.org/viewvc/llvm-project?view=rev&revision=85295">defaults
539to compiling eagerly</a> to avoid a race condition in the lazy JIT.
540Clients that still want the lazy JIT can switch it on by calling
541<tt>ExecutionEngine::DisableLazyCompilation(false)</tt>.</li>
Jeffrey Yasskin40966a72010-02-11 01:07:39 +0000542<li>It is now possible to create more than one JIT instance in the same process.
543These JITs can generate machine code in parallel,
544although <a href="http://llvm.org/docs/ProgrammersManual.html#jitthreading">you
545still have to obey the other threading restrictions</a>.</li>
Chris Lattner0b832202008-06-08 02:45:07 +0000546</ul>
547
548</div>
549
550<!--=========================================================================-->
551<div class="doc_subsection">
Chris Lattner511433e2009-03-02 03:24:11 +0000552<a name="codegen">Target Independent Code Generator Improvements</a>
Chris Lattner0b832202008-06-08 02:45:07 +0000553</div>
554
555<div class="doc_text">
556
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000557<p>We have put a significant amount of work into the code generator
558infrastructure, which allows us to implement more aggressive algorithms and make
559it run faster:</p>
Chris Lattner0b832202008-06-08 02:45:07 +0000560
561<ul>
Chris Lattner511433e2009-03-02 03:24:11 +0000562
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000563<li>...</li>
Chris Lattner84977642007-09-21 03:54:09 +0000564</ul>
Chris Lattner84977642007-09-21 03:54:09 +0000565</div>
566
Chris Lattner917cc712009-03-02 02:37:32 +0000567<!--=========================================================================-->
568<div class="doc_subsection">
569<a name="x86">X86-32 and X86-64 Target Improvements</a>
570</div>
571
572<div class="doc_text">
573<p>New features of the X86 target include:
574</p>
575
576<ul>
Chris Lattner511433e2009-03-02 03:24:11 +0000577
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000578<li>...</li>
Chris Lattner511433e2009-03-02 03:24:11 +0000579
Chris Lattner917cc712009-03-02 02:37:32 +0000580</ul>
581
Chris Lattner917cc712009-03-02 02:37:32 +0000582</div>
Chris Lattner84977642007-09-21 03:54:09 +0000583
584<!--=========================================================================-->
585<div class="doc_subsection">
Chris Lattner11398992009-02-26 07:32:11 +0000586<a name="pic16">PIC16 Target Improvements</a>
587</div>
588
589<div class="doc_text">
590<p>New features of the PIC16 target include:
591</p>
592
593<ul>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000594<li>...</li>
Chris Lattner11398992009-02-26 07:32:11 +0000595</ul>
596
597<p>Things not yet supported:</p>
598
599<ul>
Chris Lattner11398992009-02-26 07:32:11 +0000600<li>Variable arguments.</li>
Chris Lattner511433e2009-03-02 03:24:11 +0000601<li>Interrupts/programs.</li>
Chris Lattner11398992009-02-26 07:32:11 +0000602</ul>
603
604</div>
605
Chris Lattner11398992009-02-26 07:32:11 +0000606<!--=========================================================================-->
607<div class="doc_subsection">
Chris Lattner61358ab2009-10-13 17:48:04 +0000608<a name="ARM">ARM Target Improvements</a>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000609</div>
610
611<div class="doc_text">
Chris Lattner61358ab2009-10-13 17:48:04 +0000612<p>New features of the ARM target include:
613</p>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000614
615<ul>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000616
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000617<li>...</li>
Chris Lattner61358ab2009-10-13 17:48:04 +0000618</ul>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000619
Chris Lattnerc441fb82009-03-01 02:30:21 +0000620
Chris Lattner61358ab2009-10-13 17:48:04 +0000621</div>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000622
Chris Lattner61358ab2009-10-13 17:48:04 +0000623<!--=========================================================================-->
624<div class="doc_subsection">
625<a name="OtherTarget">Other Target Specific Improvements</a>
626</div>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000627
Chris Lattner61358ab2009-10-13 17:48:04 +0000628<div class="doc_text">
629<p>New features of other targets include:
630</p>
631
632<ul>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000633<li>...</li>
Chris Lattner61358ab2009-10-13 17:48:04 +0000634</ul>
635
636</div>
637
638<!--=========================================================================-->
639<div class="doc_subsection">
640<a name="newapis">New Useful APIs</a>
641</div>
642
643<div class="doc_text">
644
645<p>This release includes a number of new APIs that are used internally, which
646 may also be useful for external clients.
647</p>
648
649<ul>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000650<li>...</li>
Chris Lattner61358ab2009-10-13 17:48:04 +0000651</ul>
652
653
654</div>
655
656<!--=========================================================================-->
657<div class="doc_subsection">
658<a name="otherimprovements">Other Improvements and New Features</a>
659</div>
660
661<div class="doc_text">
662<p>Other miscellaneous features include:</p>
663
664<ul>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000665<li>...</li>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000666</ul>
667
668</div>
669
Chris Lattner77d29b12008-06-05 08:02:49 +0000670
671<!--=========================================================================-->
672<div class="doc_subsection">
Chris Lattnerf6662f92008-10-13 17:57:36 +0000673<a name="changes">Major Changes and Removed Features</a>
674</div>
675
676<div class="doc_text">
677
Chris Lattnereeb4da02008-10-13 22:06:31 +0000678<p>If you're already an LLVM user or developer with out-of-tree changes based
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000679on LLVM 2.6, this section lists some "gotchas" that you may run into upgrading
Chris Lattnereeb4da02008-10-13 22:06:31 +0000680from the previous release.</p>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000681
682<ul>
Jeffrey Yasskinbc83d062010-02-09 23:03:44 +0000683<li>The LLVM interpreter now defaults to <em>not</em> using <tt>libffi</tt> even
684if you have it installed. This makes it more likely that an LLVM built on one
685system will work when copied to a similar system. To use <tt>libffi</tt>,
686configure with <tt>--enable-libffi</tt>.
687</li>
Chris Lattnereeb4da02008-10-13 22:06:31 +0000688</ul>
689
690
691<p>In addition, many APIs have changed in this release. Some of the major LLVM
692API changes are:</p>
693
694<ul>
Jeffrey Yasskin4fcd6072010-01-28 01:41:20 +0000695<li><tt>ModuleProvider</tt> has been <a
696href="http://llvm.org/viewvc/llvm-project?view=rev&revision=94686">removed</a>
697and its methods moved to <tt>Module</tt> and <tt>GlobalValue</tt>.
698Most clients can remove uses of <tt>ExistingModuleProvider</tt>,
699replace <tt>getBitcodeModuleProvider</tt> with
700<tt>getLazyBitcodeModule</tt>, and pass their <tt>Module</tt> to
701functions that used to accept <tt>ModuleProvider</tt>. Clients who
702wrote their own <tt>ModuleProvider</tt>s will need to derive from
703<tt>GVMaterializer</tt> instead and use
704<tt>Module::setMaterializer</tt> to attach it to a
705<tt>Module</tt>.</li>
706
707<li><tt>GhostLinkage</tt> has given up the ghost.
708<tt>GlobalValue</tt>s that have not yet been read from their backing
709storage have the same linkage they will have after being read in.
710Clients must replace calls to
711<tt>GlobalValue::hasNotBeenReadFromBitcode</tt> with
712<tt>GlobalValue::isMaterializable</tt>.</li>
Daniel Dunbar4acdede2010-02-10 04:09:52 +0000713
714<li>FIXME: Debug info has been totally redone. Add pointers to new APIs. Substantial caveats about compatibility of .ll and .bc files.</li>
715
Daniel Dunbarca1c8162010-02-14 01:47:19 +0000716<li>The <tt>llvm/Support/DataTypes.h</tt> header has moved
717to <tt>llvm/System/DataTypes.h</tt>.</li>
718
Duncan Sands411432d2010-02-17 17:20:17 +0000719<li>The <tt>isInteger</tt>, <tt>isIntOrIntVector</tt>, <tt>isFloatingPoint</tt>,
720<tt>isFPOrFPVector</tt> and <tt>isFPOrFPVector</tt> methods have been renamed
721<tt>isIntegerTy</tt>, <tt>isIntOrIntVectorTy</tt>, <tt>isFloatingPointTy</tt>,
722<tt>isFPOrFPVectorTy</tt> and <tt>isFPOrFPVectorTy</tt> respectively.</li>
Devang Patelb34dd132008-10-14 20:03:43 +0000723</ul>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000724
Chris Lattnerf6662f92008-10-13 17:57:36 +0000725</div>
726
727
728
Chris Lattner19092612003-10-02 16:38:05 +0000729<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000730<div class="doc_section">
731 <a name="portability">Portability and Supported Platforms</a>
732</div>
Chris Lattner19092612003-10-02 16:38:05 +0000733<!-- *********************************************************************** -->
734
Misha Brukman500bc302003-11-22 00:38:41 +0000735<div class="doc_text">
736
John Criswell0b5b5e92004-12-08 20:35:47 +0000737<p>LLVM is known to work on the following platforms:</p>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000738
739<ul>
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000740<li>Intel and AMD machines (IA32, X86-64, AMD64, EMT-64) running Red Hat
Chris Lattner61358ab2009-10-13 17:48:04 +0000741 Linux, Fedora Core, FreeBSD and AuroraUX (and probably other unix-like
742 systems).</li>
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000743<li>PowerPC and X86-based Mac OS X systems, running 10.3 and above in 32-bit
Chris Lattner61358ab2009-10-13 17:48:04 +0000744 and 64-bit modes.</li>
Chris Lattner252b83d2008-02-06 18:00:06 +0000745<li>Intel and AMD machines running on Win32 using MinGW libraries (native).</li>
Chris Lattner57a460e2007-05-23 04:39:32 +0000746<li>Intel and AMD machines running on Win32 with the Cygwin libraries (limited
747 support is available for native builds with Visual C++).</li>
Chris Lattner7e23d6e2009-10-16 16:30:58 +0000748<li>Sun x86 and AMD64 machines running Solaris 10, OpenSolaris 0906.</li>
John Criswell9321fa82005-05-13 20:28:15 +0000749<li>Alpha-based machines running Debian GNU/Linux.</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000750</ul>
751
Chris Lattnerbc5786b2008-06-05 06:57:39 +0000752<p>The core LLVM infrastructure uses GNU autoconf to adapt itself
Brian Gaekeb0fd7612004-05-09 05:28:35 +0000753to the machine and operating system on which it is built. However, minor
754porting may be required to get LLVM to work on new platforms. We welcome your
755portability patches and reports of successful builds or error messages.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000756
Misha Brukman500bc302003-11-22 00:38:41 +0000757</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000758
759<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000760<div class="doc_section">
761 <a name="knownproblems">Known Problems</a>
762</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000763<!-- *********************************************************************** -->
764
Misha Brukman500bc302003-11-22 00:38:41 +0000765<div class="doc_text">
766
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000767<p>This section contains significant known problems with the LLVM system,
Chris Lattnere18b32e2008-11-10 05:40:34 +0000768listed by component. If you run into a problem, please check the <a
Chris Lattnerc463b272005-10-29 07:07:09 +0000769href="http://llvm.org/bugs/">LLVM bug database</a> and submit a bug if
Chris Lattner5eccca42003-12-12 21:22:16 +0000770there isn't already one.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000771
Chris Lattner477a1fd2010-03-17 17:25:49 +0000772<ul>
Chris Lattner61358ab2009-10-13 17:48:04 +0000773<li>LLVM will not correctly compile on Solaris and/or OpenSolaris
774using the stock GCC 3.x.x series 'out the box',
Chris Lattner554ee4a2009-11-03 21:50:09 +0000775See: <a href="GettingStarted.html#brokengcc">Broken versions of GCC and other tools</a>.
Chris Lattner61358ab2009-10-13 17:48:04 +0000776However, A <a href="http://pkg.auroraux.org/GCC">Modern GCC Build</a>
777for x86/x86-64 has been made available from the third party AuroraUX Project
778that has been meticulously tested for bootstrapping LLVM &amp; Clang.</li>
779</ul>
780
Misha Brukman500bc302003-11-22 00:38:41 +0000781</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000782
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000783<!-- ======================================================================= -->
784<div class="doc_subsection">
785 <a name="experimental">Experimental features included with this release</a>
786</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000787
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000788<div class="doc_text">
789
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000790<p>The following components of this LLVM release are either untested, known to
791be broken or unreliable, or are in early development. These components should
792not be relied on, and bugs should not be filed against them, but they may be
793useful to some people. In particular, if you would like to work on one of these
Chris Lattner2b659ef2008-02-12 06:29:45 +0000794components, please contact us on the <a
795href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev list</a>.</p>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000796
797<ul>
Chris Lattner61358ab2009-10-13 17:48:04 +0000798<li>The MSIL, Alpha, SPU, MIPS, PIC16, Blackfin, MSP430 and SystemZ backends are
799 experimental.</li>
Bill Wendling99dac472009-03-02 07:54:14 +0000800<li>The <tt>llc</tt> "<tt>-filetype=asm</tt>" (the default) is the only
Chris Lattnerc66bfef2010-03-17 04:41:49 +0000801 supported value for this option. The MachO writer is experimental, and
802 works much better in mainline SVN.</li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000803</ul>
804
805</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000806
Misha Brukman500bc302003-11-22 00:38:41 +0000807<!-- ======================================================================= -->
808<div class="doc_subsection">
Chris Lattner26299222006-11-18 07:51:14 +0000809 <a name="x86-be">Known problems with the X86 back-end</a>
John Criswellc0c186d2005-11-08 21:11:33 +0000810</div>
811
812<div class="doc_text">
813
814<ul>
Anton Korobeynikova6094be2008-06-08 10:24:13 +0000815 <li>The X86 backend does not yet support
816 all <a href="http://llvm.org/PR879">inline assembly that uses the X86
817 floating point stack</a>. It supports the 'f' and 't' constraints, but not
818 'u'.</li>
Chris Lattnere6e1b352008-06-08 21:19:07 +0000819 <li>The X86 backend generates inefficient floating point code when configured
820 to generate code for systems that don't have SSE2.</li>
Duncan Sands47eff2b2008-06-08 19:38:43 +0000821 <li>Win64 code generation wasn't widely tested. Everything should work, but we
John Criswell524a5dd2009-03-02 15:28:15 +0000822 expect small issues to happen. Also, llvm-gcc cannot build the mingw64
823 runtime currently due
Anton Korobeynikova6094be2008-06-08 10:24:13 +0000824 to <a href="http://llvm.org/PR2255">several</a>
John Criswell524a5dd2009-03-02 15:28:15 +0000825 <a href="http://llvm.org/PR2257">bugs</a> and due to lack of support for
826 the
827 'u' inline assembly constraint and for X87 floating point inline assembly.</li>
Dan Gohman8207ba92008-06-08 23:05:11 +0000828 <li>The X86-64 backend does not yet support the LLVM IR instruction
Chris Lattner917cc712009-03-02 02:37:32 +0000829 <tt>va_arg</tt>. Currently, the llvm-gcc and front-ends support variadic
Dan Gohman8207ba92008-06-08 23:05:11 +0000830 argument constructs on X86-64 by lowering them manually.</li>
Chris Lattner26299222006-11-18 07:51:14 +0000831</ul>
832
833</div>
834
835<!-- ======================================================================= -->
836<div class="doc_subsection">
837 <a name="ppc-be">Known problems with the PowerPC back-end</a>
838</div>
839
840<div class="doc_text">
841
842<ul>
Nicolas Geoffraye4285dc2007-05-15 09:21:28 +0000843<li>The Linux PPC32/ABI support needs testing for the interpreter and static
Chris Lattner57a460e2007-05-23 04:39:32 +0000844compilation, and lacks support for debug information.</li>
Chris Lattner26299222006-11-18 07:51:14 +0000845</ul>
846
847</div>
848
849<!-- ======================================================================= -->
850<div class="doc_subsection">
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000851 <a name="arm-be">Known problems with the ARM back-end</a>
852</div>
853
854<div class="doc_text">
855
856<ul>
Chris Lattner61358ab2009-10-13 17:48:04 +0000857<li>Support for the Advanced SIMD (Neon) instruction set is still incomplete
858and not well tested. Some features may not work at all, and the code quality
859may be poor in some cases.</li>
Chris Lattner57a460e2007-05-23 04:39:32 +0000860<li>Thumb mode works only on ARMv6 or higher processors. On sub-ARMv6
Duncan Sandsc90d68b2007-09-26 15:59:54 +0000861processors, thumb programs can crash or produce wrong
Chris Lattner57a460e2007-05-23 04:39:32 +0000862results (<a href="http://llvm.org/PR1388">PR1388</a>).</li>
John Criswell524a5dd2009-03-02 15:28:15 +0000863<li>Compilation for ARM Linux OABI (old ABI) is supported but not fully tested.
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000864</li>
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000865</ul>
866
867</div>
868
869<!-- ======================================================================= -->
870<div class="doc_subsection">
Chris Lattner26299222006-11-18 07:51:14 +0000871 <a name="sparc-be">Known problems with the SPARC back-end</a>
872</div>
873
874<div class="doc_text">
875
876<ul>
John Criswell524a5dd2009-03-02 15:28:15 +0000877<li>The SPARC backend only supports the 32-bit SPARC ABI (-m32); it does not
Chris Lattner26299222006-11-18 07:51:14 +0000878 support the 64-bit SPARC ABI (-m64).</li>
879</ul>
880
881</div>
882
883<!-- ======================================================================= -->
884<div class="doc_subsection">
Bruno Cardoso Lopesb7e1a4f2008-10-25 14:56:26 +0000885 <a name="mips-be">Known problems with the MIPS back-end</a>
886</div>
887
888<div class="doc_text">
889
890<ul>
Bruno Cardoso Lopesb7e1a4f2008-10-25 14:56:26 +0000891<li>64-bit MIPS targets are not supported yet.</li>
892</ul>
893
894</div>
895
896<!-- ======================================================================= -->
897<div class="doc_subsection">
Chris Lattner26299222006-11-18 07:51:14 +0000898 <a name="alpha-be">Known problems with the Alpha back-end</a>
899</div>
900
901<div class="doc_text">
902
903<ul>
904
905<li>On 21164s, some rare FP arithmetic sequences which may trap do not have the
906appropriate nops inserted to ensure restartability.</li>
907
John Criswellc0c186d2005-11-08 21:11:33 +0000908</ul>
909</div>
910
Chris Lattner26299222006-11-18 07:51:14 +0000911<!-- ======================================================================= -->
912<div class="doc_subsection">
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000913 <a name="c-be">Known problems with the C back-end</a>
Chris Lattner26299222006-11-18 07:51:14 +0000914</div>
915
916<div class="doc_text">
917
918<ul>
Chris Lattner5733b272008-06-05 06:35:40 +0000919<li><a href="http://llvm.org/PR802">The C backend has only basic support for
920 inline assembly code</a>.</li>
Chris Lattner725a0d82007-09-26 06:01:35 +0000921<li><a href="http://llvm.org/PR1658">The C backend violates the ABI of common
922 C++ programs</a>, preventing intermixing between C++ compiled by the CBE and
Gabor Greif4906abe2009-03-02 12:02:51 +0000923 C++ code compiled with <tt>llc</tt> or native compilers.</li>
Duncan Sandsf74c0cc2008-02-10 13:40:55 +0000924<li>The C backend does not support all exception handling constructs.</li>
Duncan Sands50723a92009-02-25 11:51:54 +0000925<li>The C backend does not support arbitrary precision integers.</li>
Chris Lattner26299222006-11-18 07:51:14 +0000926</ul>
927
928</div>
John Criswellc0c186d2005-11-08 21:11:33 +0000929
Misha Brukman500bc302003-11-22 00:38:41 +0000930
931<!-- ======================================================================= -->
932<div class="doc_subsection">
Chris Lattnerc66bfef2010-03-17 04:41:49 +0000933 <a name="c-fe">Known problems with the llvm-gcc C and C++ front-end</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000934</div>
Chris Lattner47588f92003-10-02 05:07:23 +0000935
Misha Brukman500bc302003-11-22 00:38:41 +0000936<div class="doc_text">
Chris Lattnerc5d658a2006-03-03 00:34:26 +0000937
Chris Lattner5733b272008-06-05 06:35:40 +0000938<p>The only major language feature of GCC not supported by llvm-gcc is
939 the <tt>__builtin_apply</tt> family of builtins. However, some extensions
940 are only supported on some targets. For example, trampolines are only
Duncan Sands27aff872008-06-08 20:18:35 +0000941 supported on some targets (these are used when you take the address of a
942 nested function).</p>
Misha Brukman500bc302003-11-22 00:38:41 +0000943
Chris Lattner5733b272008-06-05 06:35:40 +0000944<p>If you run into GCC extensions which are not supported, please let us know.
945</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000946
Misha Brukman500bc302003-11-22 00:38:41 +0000947</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000948
Misha Brukman500bc302003-11-22 00:38:41 +0000949<!-- ======================================================================= -->
950<div class="doc_subsection">
Chris Lattner1eb4df62008-10-30 03:58:13 +0000951 <a name="fortran-fe">Known problems with the llvm-gcc Fortran front-end</a>
952</div>
953
954<div class="doc_text">
Gabor Greifba10fe02008-11-04 21:50:59 +0000955<ul>
Chris Lattner1eb4df62008-10-30 03:58:13 +0000956<li>Fortran support generally works, but there are still several unresolved bugs
Chris Lattner61358ab2009-10-13 17:48:04 +0000957 in <a href="http://llvm.org/bugs/">Bugzilla</a>. Please see the
958 tools/gfortran component for details.</li>
Gabor Greifba10fe02008-11-04 21:50:59 +0000959</ul>
Chris Lattner1eb4df62008-10-30 03:58:13 +0000960</div>
Misha Brukman500bc302003-11-22 00:38:41 +0000961
Chris Lattner2b659ef2008-02-12 06:29:45 +0000962<!-- ======================================================================= -->
963<div class="doc_subsection">
Chris Lattner5733b272008-06-05 06:35:40 +0000964 <a name="ada-fe">Known problems with the llvm-gcc Ada front-end</a>
Chris Lattner2b659ef2008-02-12 06:29:45 +0000965</div>
966
967<div class="doc_text">
John Criswell524a5dd2009-03-02 15:28:15 +0000968The llvm-gcc 4.2 Ada compiler works fairly well; however, this is not a mature
969technology, and problems should be expected.
Chris Lattner2b659ef2008-02-12 06:29:45 +0000970<ul>
Duncan Sands27aff872008-06-08 20:18:35 +0000971<li>The Ada front-end currently only builds on X86-32. This is mainly due
John Criswell524a5dd2009-03-02 15:28:15 +0000972to lack of trampoline support (pointers to nested functions) on other platforms.
973However, it <a href="http://llvm.org/PR2006">also fails to build on X86-64</a>
Chris Lattner2b659ef2008-02-12 06:29:45 +0000974which does support trampolines.</li>
975<li>The Ada front-end <a href="http://llvm.org/PR2007">fails to bootstrap</a>.
Duncan Sands326a4982009-02-25 11:59:06 +0000976This is due to lack of LLVM support for <tt>setjmp</tt>/<tt>longjmp</tt> style
977exception handling, which is used internally by the compiler.
Chris Lattner61358ab2009-10-13 17:48:04 +0000978Workaround: configure with <tt>--disable-bootstrap</tt>.</li>
Duncan Sands978bcee2008-10-13 17:27:23 +0000979<li>The c380004, <a href="http://llvm.org/PR2010">c393010</a>
980and <a href="http://llvm.org/PR2421">cxg2021</a> ACATS tests fail
Duncan Sands326a4982009-02-25 11:59:06 +0000981(c380004 also fails with gcc-4.2 mainline).
982If the compiler is built with checks disabled then <a href="http://llvm.org/PR2010">c393010</a>
983causes the compiler to go into an infinite loop, using up all system memory.</li>
Duncan Sandsdd3e6722009-03-02 16:35:57 +0000984<li>Some GCC specific Ada tests continue to crash the compiler.</li>
Chris Lattner61358ab2009-10-13 17:48:04 +0000985<li>The <tt>-E</tt> binder option (exception backtraces)
Chris Lattner2b659ef2008-02-12 06:29:45 +0000986<a href="http://llvm.org/PR1982">does not work</a> and will result in programs
Chris Lattner61358ab2009-10-13 17:48:04 +0000987crashing if an exception is raised. Workaround: do not use <tt>-E</tt>.</li>
Chris Lattner2b659ef2008-02-12 06:29:45 +0000988<li>Only discrete types <a href="http://llvm.org/PR1981">are allowed to start
989or finish at a non-byte offset</a> in a record. Workaround: do not pack records
990or use representation clauses that result in a field of a non-discrete type
991starting or finishing in the middle of a byte.</li>
Chris Lattnere6e1b352008-06-08 21:19:07 +0000992<li>The <tt>lli</tt> interpreter <a href="http://llvm.org/PR2009">considers
993'main' as generated by the Ada binder to be invalid</a>.
994Workaround: hand edit the file to use pointers for <tt>argv</tt> and
995<tt>envp</tt> rather than integers.</li>
996<li>The <tt>-fstack-check</tt> option <a href="http://llvm.org/PR2008">is
997ignored</a>.</li>
Chris Lattner2b659ef2008-02-12 06:29:45 +0000998</ul>
999</div>
1000
Chris Lattner61358ab2009-10-13 17:48:04 +00001001<!-- ======================================================================= -->
1002<div class="doc_subsection">
1003 <a name="ocaml-bindings">Known problems with the O'Caml bindings</a>
1004</div>
1005
1006<div class="doc_text">
1007
1008<p>The <tt>Llvm.Linkage</tt> module is broken, and has incorrect values. Only
1009<tt>Llvm.Linkage.External</tt>, <tt>Llvm.Linkage.Available_externally</tt>, and
1010<tt>Llvm.Linkage.Link_once</tt> will be correct. If you need any of the other linkage
1011modes, you'll have to write an external C library in order to expose the
1012functionality. This has been fixed in the trunk.</p>
1013</div>
1014
Chris Lattner79c3fe12003-10-02 04:57:28 +00001015<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +00001016<div class="doc_section">
1017 <a name="additionalinfo">Additional Information</a>
1018</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +00001019<!-- *********************************************************************** -->
1020
Misha Brukman500bc302003-11-22 00:38:41 +00001021<div class="doc_text">
1022
Chris Lattner416db102005-05-16 17:13:10 +00001023<p>A wide variety of additional information is available on the <a
Chris Lattnerb4b0ce72007-05-18 00:44:29 +00001024href="http://llvm.org">LLVM web page</a>, in particular in the <a
1025href="http://llvm.org/docs/">documentation</a> section. The web page also
Reid Spencer669ed452007-07-09 08:04:31 +00001026contains versions of the API documentation which is up-to-date with the
1027Subversion version of the source code.
Misha Brukman109d9e82005-03-30 19:14:24 +00001028You can access versions of these documents specific to this release by going
1029into the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +00001030
Misha Brukman500bc302003-11-22 00:38:41 +00001031<p>If you have any questions or comments about LLVM, please feel free to contact
Chris Lattnerc463b272005-10-29 07:07:09 +00001032us via the <a href="http://llvm.org/docs/#maillist"> mailing
Chris Lattner5eccca42003-12-12 21:22:16 +00001033lists</a>.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +00001034
Misha Brukman500bc302003-11-22 00:38:41 +00001035</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +00001036
1037<!-- *********************************************************************** -->
Chris Lattner79c3fe12003-10-02 04:57:28 +00001038
Misha Brukman500bc302003-11-22 00:38:41 +00001039<hr>
Misha Brukman2061e892003-11-22 01:23:39 +00001040<address>
Misha Brukman38847d52003-12-21 22:53:21 +00001041 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman44408702008-12-11 17:34:48 +00001042 src="http://jigsaw.w3.org/css-validator/images/vcss-blue" alt="Valid CSS"></a>
Misha Brukman2061e892003-11-22 01:23:39 +00001043 <a href="http://validator.w3.org/check/referer"><img
Misha Brukman44408702008-12-11 17:34:48 +00001044 src="http://www.w3.org/Icons/valid-html401-blue" alt="Valid HTML 4.01"></a>
Misha Brukman2061e892003-11-22 01:23:39 +00001045
Chris Lattnerb4b0ce72007-05-18 00:44:29 +00001046 <a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br>
Misha Brukman500bc302003-11-22 00:38:41 +00001047 Last modified: $Date$
Misha Brukman2061e892003-11-22 01:23:39 +00001048</address>
Chris Lattner79c3fe12003-10-02 04:57:28 +00001049
Misha Brukman500bc302003-11-22 00:38:41 +00001050</body>
1051</html>