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Jeffrey Yasskinbec48772010-01-28 01:14:43 +00007 <title>LLVM 2.7 Release Notes</title>
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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
Chris Lattner00736fc2010-04-13 06:37:00 +000031<!--
Jeffrey Yasskinbec48772010-01-28 01:14:43 +000032<h1 style="color:red">These are in-progress notes for the upcoming LLVM 2.7
33release.<br>
34You may prefer the
35<a href="http://llvm.org/releases/2.6/docs/ReleaseNotes.html">LLVM 2.6
Chris Lattner00736fc2010-04-13 06:37:00 +000036Release Notes</a>.</h1>-->
Jeffrey Yasskinbec48772010-01-28 01:14:43 +000037
Chris Lattner79c3fe12003-10-02 04:57:28 +000038<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +000039<div class="doc_section">
40 <a name="intro">Introduction</a>
41</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +000042<!-- *********************************************************************** -->
43
Misha Brukman500bc302003-11-22 00:38:41 +000044<div class="doc_text">
45
Chris Lattnerf6662f92008-10-13 17:57:36 +000046<p>This document contains the release notes for the LLVM Compiler
Jeffrey Yasskinbec48772010-01-28 01:14:43 +000047Infrastructure, release 2.7. Here we describe the status of LLVM, including
Chris Lattnerf6662f92008-10-13 17:57:36 +000048major improvements from the previous release and significant known problems.
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +000049All LLVM releases may be downloaded from the <a
Chris Lattnerf6662f92008-10-13 17:57:36 +000050href="http://llvm.org/releases/">LLVM releases web site</a>.</p>
Chris Lattner19092612003-10-02 16:38:05 +000051
Chris Lattner7506b1d2004-12-07 08:04:13 +000052<p>For more information about LLVM, including information about the latest
Chris Lattnerc463b272005-10-29 07:07:09 +000053release, please check out the <a href="http://llvm.org/">main LLVM
Chris Lattner47ad72c2003-10-07 21:38:31 +000054web site</a>. If you have questions or comments, the <a
Chris Lattnerc66bfef2010-03-17 04:41:49 +000055href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM Developer's
56Mailing List</a> is a good place to send them.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +000057
Mikhail Glushenkovea65d7d2008-10-13 02:08:34 +000058<p>Note that if you are reading this file from a Subversion checkout or the
Chris Lattner84977642007-09-21 03:54:09 +000059main LLVM web page, this document applies to the <i>next</i> release, not the
Gabor Greiffa933f82008-10-14 11:00:32 +000060current one. To see the release notes for a specific release, please see the
Chris Lattner84977642007-09-21 03:54:09 +000061<a href="http://llvm.org/releases/">releases page</a>.</p>
Misha Brukman500bc302003-11-22 00:38:41 +000062
Chris Lattnerc66bfef2010-03-17 04:41:49 +000063
Chris Lattnerdc910082010-03-17 06:41:58 +000064<p>FIXME: llvm.org moved to new server, mention new logo, Ted and Doug new code
Chris Lattner8b5d9c82010-04-16 06:20:22 +000065 owners, web page in llvm-www repos.</p>
Chris Lattnerc66bfef2010-03-17 04:41:49 +000066
Misha Brukman500bc302003-11-22 00:38:41 +000067</div>
Chris Lattner61358ab2009-10-13 17:48:04 +000068
Chris Lattner79c3fe12003-10-02 04:57:28 +000069
Chris Lattner61358ab2009-10-13 17:48:04 +000070<!--
71Almost dead code.
72 include/llvm/Analysis/LiveValues.h => Dan
73 lib/Transforms/IPO/MergeFunctions.cpp => consider for 2.8.
74 llvm/Analysis/PointerTracking.h => Edwin wants this, consider for 2.8.
Chris Lattner00736fc2010-04-13 06:37:00 +000075 ABCD, GEPSplitterPass
Chris Lattner048fe3c2010-01-16 21:25:13 +000076 MSIL backend?
Chris Lattnerdc910082010-03-17 06:41:58 +000077 lib/Transforms/Utils/SSI.cpp -> ABCD depends on it.
Chris Lattner61358ab2009-10-13 17:48:04 +000078-->
79
80
Jeffrey Yasskinbec48772010-01-28 01:14:43 +000081<!-- Features that need text if they're finished for 2.7:
Chris Lattner61358ab2009-10-13 17:48:04 +000082 gcc plugin.
83 strong phi elim
84 variable debug info for optimized code
Chris Lattnerab68e9e2009-02-26 22:33:38 +000085 postalloc scheduler: anti dependence breaking, hazard recognizer?
Chris Lattner61358ab2009-10-13 17:48:04 +000086 metadata
87 loop dependence analysis
88 ELF Writer? How stable?
89 <li>PostRA scheduler improvements, ARM adoption (David Goodwin).</li>
Chris Lattneracce85d2008-02-10 07:46:44 +000090 -->
Mikhail Glushenkovea65d7d2008-10-13 02:08:34 +000091
Chris Lattner547a3912008-10-12 19:47:48 +000092 <!-- for announcement email:
Chris Lattner61358ab2009-10-13 17:48:04 +000093 Logo web page.
94 llvm devmtg
95 compiler_rt
96 KLEE web page at klee.llvm.org
97 Many new papers added to /pubs/
Chris Lattnerdc910082010-03-17 06:41:58 +000098 Mention gcc plugin.
Chris Lattner74c80df2009-02-25 06:34:50 +000099 -->
Chris Lattneracce85d2008-02-10 07:46:44 +0000100
Chris Lattner96a445e2008-10-13 18:01:01 +0000101<!-- *********************************************************************** -->
102<div class="doc_section">
103 <a name="subproj">Sub-project Status Update</a>
Chris Lattnerea34f642008-06-08 21:34:41 +0000104</div>
Chris Lattner96a445e2008-10-13 18:01:01 +0000105<!-- *********************************************************************** -->
Chris Lattnerea34f642008-06-08 21:34:41 +0000106
107<div class="doc_text">
Chris Lattner8348b472008-06-08 21:58:17 +0000108<p>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000109The LLVM 2.7 distribution currently consists of code from the core LLVM
Chris Lattner61358ab2009-10-13 17:48:04 +0000110repository (which roughly includes the LLVM optimizers, code generators
111and supporting tools), the Clang repository and the llvm-gcc repository. In
112addition to this code, the LLVM Project includes other sub-projects that are in
113development. Here we include updates on these subprojects.
Bill Wendling63d8c552009-03-02 04:28:57 +0000114</p>
Chris Lattner96a445e2008-10-13 18:01:01 +0000115
Chris Lattner8348b472008-06-08 21:58:17 +0000116</div>
117
Chris Lattner96a445e2008-10-13 18:01:01 +0000118
Chris Lattner8348b472008-06-08 21:58:17 +0000119<!--=========================================================================-->
Chris Lattner96a445e2008-10-13 18:01:01 +0000120<div class="doc_subsection">
Chris Lattnerfb97b2d2008-10-13 18:11:54 +0000121<a name="clang">Clang: C/C++/Objective-C Frontend Toolkit</a>
Chris Lattner8348b472008-06-08 21:58:17 +0000122</div>
123
124<div class="doc_text">
125
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000126<p>The <a href="http://clang.llvm.org/">Clang project</a> is ...</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000127
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000128<p>In the LLVM 2.7 time-frame, the Clang team has made many improvements:</p>
Bill Wendling741748a2008-10-27 09:27:33 +0000129
Daniel Dunbar13739432008-10-14 23:25:09 +0000130<ul>
Daniel Dunbar60dadb62010-03-25 16:09:18 +0000131<li>FIXME: C++! Include a link to cxx_compatibility.html</li>
132
133<li>FIXME: Static Analyzer improvements?</li>
134
135<li>CIndex API and Python bindings: Clang now includes a C API as part of the
136CIndex library. Although we make make some changes to the API in the future, it
137is intended to be stable and has been designed for use by external projects. See
138the Clang
139doxygen <a href="http://clang.llvm.org/doxygen/group__CINDEX.html">CIndex</a>
140documentation for more details. The CIndex API also includings an preliminary
141set of Python bindings.</li>
142
143<li>ARM Support: Clang now has ABI support for both the Darwin and Linux ARM
144ABIs. Coupled with many improvements to the LLVM ARM backend, Clang is now
145suitable for use as a a beta quality ARM compiler.</li>
Bill Wendling6bc15282009-03-02 04:28:18 +0000146</ul>
Chris Lattnerfb97b2d2008-10-13 18:11:54 +0000147</div>
148
149<!--=========================================================================-->
150<div class="doc_subsection">
151<a name="clangsa">Clang Static Analyzer</a>
152</div>
153
154<div class="doc_text">
155
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000156<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 +0000157includes an early stage static source code analysis tool for <a
158href="http://clang.llvm.org/StaticAnalysis.html">automatically finding bugs</a>
Chris Lattner61358ab2009-10-13 17:48:04 +0000159in C and Objective-C programs. The tool performs checks to find
Ted Kremenek8b3894c2009-02-27 07:01:32 +0000160bugs that occur on a specific path within a program.</p>
Chris Lattnercc042612008-10-14 00:52:49 +0000161
Chris Lattner0e464a92010-03-17 04:02:39 +0000162<p>In the LLVM 2.7 time-frame, the analyzer core has sprouted legs and...</p>
Chris Lattner8348b472008-06-08 21:58:17 +0000163
164</div>
165
Chris Lattner96a445e2008-10-13 18:01:01 +0000166<!--=========================================================================-->
167<div class="doc_subsection">
Nicolas Geoffray99a4d302008-10-14 19:23:04 +0000168<a name="vmkit">VMKit: JVM/CLI Virtual Machine Implementation</a>
Chris Lattner96a445e2008-10-13 18:01:01 +0000169</div>
170
171<div class="doc_text">
172<p>
Nicolas Geoffray99a4d302008-10-14 19:23:04 +0000173The <a href="http://vmkit.llvm.org/">VMKit project</a> is an implementation of
Chris Lattner61358ab2009-10-13 17:48:04 +0000174a JVM and a CLI Virtual Machine (Microsoft .NET is an
175implementation of the CLI) using LLVM for static and just-in-time
176compilation.</p>
Chris Lattner96a445e2008-10-13 18:01:01 +0000177
Chris Lattner61358ab2009-10-13 17:48:04 +0000178<p>
Chris Lattnerbf8e5162010-03-29 18:34:13 +0000179With the release of LLVM 2.7, VMKit has shifted to a great framework for writing
180virtual machines. VMKit now offers precise and efficient garbage collection with
181multi-threading support, thanks to the MMTk memory management toolkit, as well
182as just in time and ahead of time compilation with LLVM. The major changes in
183VMKit 0.27 are:</p>
Chris Lattner96a445e2008-10-13 18:01:01 +0000184
Nicolas Geoffray99a4d302008-10-14 19:23:04 +0000185<ul>
186
Chris Lattnerbf8e5162010-03-29 18:34:13 +0000187<li>Garbage collection: VMKit now uses the MMTk toolkit for garbage collectors.
188 The first collector to be ported is the MarkSweep collector, which is precise,
189 and drastically improves the performance of VMKit.</li>
190<li>Line number information in the JVM: by using the debug metadata of LLVM, the
191 JVM now supports precise line number information, useful when printing a stack
192 trace.</li>
193<li>Interface calls in the JVM: we implemented a variant of the Interface Method
194 Table technique for interface calls in the JVM.
195</li>
Nicolas Geoffray99a4d302008-10-14 19:23:04 +0000196
197</ul>
Chris Lattner96a445e2008-10-13 18:01:01 +0000198</div>
199
Chris Lattner61358ab2009-10-13 17:48:04 +0000200
201<!--=========================================================================-->
202<div class="doc_subsection">
203<a name="compiler-rt">compiler-rt: Compiler Runtime Library</a>
204</div>
205
206<div class="doc_text">
207<p>
208The new LLVM <a href="http://compiler-rt.llvm.org/">compiler-rt project</a>
209is a simple library that provides an implementation of the low-level
210target-specific hooks required by code generation and other runtime components.
211For example, when compiling for a 32-bit target, converting a double to a 64-bit
212unsigned integer is compiled into a runtime call to the "__fixunsdfdi"
213function. The compiler-rt library provides highly optimized implementations of
214this and other low-level routines (some are 3x faster than the equivalent
215libgcc routines).</p>
216
217<p>
218All of the code in the compiler-rt project is available under the standard LLVM
219License, a "BSD-style" license.</p>
220
221</div>
222
223<!--=========================================================================-->
224<div class="doc_subsection">
Duncan Sands749fd832010-04-02 09:23:15 +0000225<a name="dragonegg">DragonEgg: llvm-gcc ported to gcc-4.5</a>
Chris Lattner61358ab2009-10-13 17:48:04 +0000226</div>
227
228<div class="doc_text">
229<p>
Duncan Sands749fd832010-04-02 09:23:15 +0000230<a href="http://dragonegg.llvm.org/">DragonEgg</a> is a port of llvm-gcc to
231gcc-4.5. Unlike llvm-gcc, which makes many intrusive changes to the underlying
232gcc-4.2 code, dragonegg in theory does not require any gcc-4.5 modifications
233whatsoever (currently one small patch is needed). This is thanks to the new
234<a href="http://gcc.gnu.org/wiki/plugins">gcc plugin architecture</a>, which
235makes it possible to modify the behaviour of gcc at runtime by loading a plugin,
236which is nothing more than a dynamic library which conforms to the gcc plugin
237interface. DragonEgg is a gcc plugin that causes the LLVM optimizers to be run
238instead of the gcc optimizers, and the LLVM code generators instead of the gcc
239code generators, just like llvm-gcc. To use it, you add
240"-fplugin=path/dragonegg.so" to the gcc-4.5 command line, and gcc-4.5 magically
241becomes llvm-gcc-4.5!
242</p>
243
244<p>
245DragonEgg is still a work in progress. Currently C works very well, while C++,
246Ada and Fortran work fairly well. All other languages either don't work at all,
247or only work poorly. For the moment only the x86-32 and x86-64 targets are
248supported, and only on linux.
249</p>
250
251<p>
252DragonEgg has not yet been released. Once gcc-4.5 has been released, dragonegg
253will probably be released as part of the following LLVM release.
Chris Lattner61358ab2009-10-13 17:48:04 +0000254</p>
255
256</div>
257
258
259<!--=========================================================================-->
260<div class="doc_subsection">
261<a name="mc">llvm-mc: Machine Code Toolkit</a>
262</div>
263
264<div class="doc_text">
265<p>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000266The LLVM Machine Code (MC) Toolkit project is ...
Chris Lattner61358ab2009-10-13 17:48:04 +0000267</p>
268
269</div>
270
271
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000272<!-- *********************************************************************** -->
273<div class="doc_section">
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000274 <a name="externalproj">External Open Source Projects Using LLVM 2.7</a>
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000275</div>
276<!-- *********************************************************************** -->
277
Chris Lattner61358ab2009-10-13 17:48:04 +0000278<div class="doc_text">
279
280<p>An exciting aspect of LLVM is that it is used as an enabling technology for
281 a lot of other language and tools projects. This section lists some of the
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000282 projects that have already been updated to work with LLVM 2.7.</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000283</div>
284
285
286<!--=========================================================================-->
287<div class="doc_subsection">
288<a name="Rubinius">Rubinius</a>
289</div>
290
291<div class="doc_text">
Chris Lattner0e464a92010-03-17 04:02:39 +0000292Need update.
293<!--
Chris Lattner61358ab2009-10-13 17:48:04 +0000294<p><a href="http://github.com/evanphx/rubinius">Rubinius</a> is an environment
295for running Ruby code which strives to write as much of the core class
296implementation in Ruby as possible. Combined with a bytecode interpreting VM, it
297uses LLVM to optimize and compile ruby code down to machine code. Techniques
298such as type feedback, method inlining, and uncommon traps are all used to
299remove dynamism from ruby execution and increase performance.</p>
300
301<p>Since LLVM 2.5, Rubinius has made several major leaps forward, implementing
302a counter based JIT, type feedback and speculative method inlining.
Chris Lattner0e464a92010-03-17 04:02:39 +0000303-->
Chris Lattner61358ab2009-10-13 17:48:04 +0000304</p>
305
306</div>
307
308<!--=========================================================================-->
309<div class="doc_subsection">
310<a name="macruby">MacRuby</a>
311</div>
312
313<div class="doc_text">
314
315<p>
Chris Lattner0e464a92010-03-17 04:02:39 +0000316Need update.
317<!--
Chris Lattner61358ab2009-10-13 17:48:04 +0000318<a href="http://macruby.org">MacRuby</a> is an implementation of Ruby on top of
319core Mac OS X technologies, such as the Objective-C common runtime and garbage
320collector and the CoreFoundation framework. It is principally developed by
321Apple and aims at enabling the creation of full-fledged Mac OS X applications.
322</p>
323
324<p>
325MacRuby uses LLVM for optimization passes, JIT and AOT compilation of Ruby
326expressions. It also uses zero-cost DWARF exceptions to implement Ruby exception
Chris Lattner0e464a92010-03-17 04:02:39 +0000327handling.--> </p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000328
329</div>
330
331
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000332<!--=========================================================================-->
333<div class="doc_subsection">
334<a name="pure">Pure</a>
335</div>
336
337<div class="doc_text">
338<p>
Chris Lattner917cc712009-03-02 02:37:32 +0000339<a href="http://pure-lang.googlecode.com/">Pure</a>
340is an algebraic/functional programming language based on term rewriting.
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000341Programs are collections of equations which are used to evaluate expressions in
342a symbolic fashion. Pure offers dynamic typing, eager and lazy evaluation,
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000343lexical closures, a hygienic macro system (also based on term rewriting),
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000344built-in list and matrix support (including list and matrix comprehensions) and
345an easy-to-use C interface. The interpreter uses LLVM as a backend to
346 JIT-compile Pure programs to fast native code.</p>
347
Chris Lattner477a1fd2010-03-17 17:25:49 +0000348<p>Pure versions 0.43 and later have been tested and are known to work with
349LLVM 2.7 (and continue to work with older LLVM releases >= 2.5).</p>
350
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000351</div>
352
353
354<!--=========================================================================-->
355<div class="doc_subsection">
356<a name="ldc">LLVM D Compiler</a>
357</div>
358
359<div class="doc_text">
360<p>
Chris Lattner0e464a92010-03-17 04:02:39 +0000361Need update.
362<!--
Chris Lattner917cc712009-03-02 02:37:32 +0000363<a href="http://www.dsource.org/projects/ldc">LDC</a> is an implementation of
364the D Programming Language using the LLVM optimizer and code generator.
Chris Lattner61358ab2009-10-13 17:48:04 +0000365The LDC project works great with the LLVM 2.6 release. General improvements in
John Criswell524a5dd2009-03-02 15:28:15 +0000366this
Chris Lattner917cc712009-03-02 02:37:32 +0000367cycle have included new inline asm constraint handling, better debug info
Chris Lattner61358ab2009-10-13 17:48:04 +0000368support, general bug fixes and better x86-64 support. This has allowed
369some major improvements in LDC, getting it much closer to being as
Chris Lattner0e464a92010-03-17 04:02:39 +0000370fully featured as the original DMD compiler from DigitalMars.-->
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000371</p>
372</div>
373
Chris Lattnerbc31caf2009-02-28 18:58:01 +0000374<!--=========================================================================-->
375<div class="doc_subsection">
376<a name="RoadsendPHP">Roadsend PHP</a>
377</div>
378
379<div class="doc_text">
Chris Lattner61358ab2009-10-13 17:48:04 +0000380<p>
381<a href="http://code.roadsend.com/rphp">Roadsend PHP</a> (rphp) is an open
Chris Lattnercade8222009-03-02 19:07:24 +0000382source implementation of the PHP programming
Chris Lattner61358ab2009-10-13 17:48:04 +0000383language that uses LLVM for its optimizer, JIT and static compiler. This is a
Chris Lattner0e464a92010-03-17 04:02:39 +0000384reimplementation of an earlier project that is now based on LLVM.
Chris Lattner477a1fd2010-03-17 17:25:49 +0000385</p>
Chris Lattnerbc31caf2009-02-28 18:58:01 +0000386</div>
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000387
Chris Lattner61358ab2009-10-13 17:48:04 +0000388<!--=========================================================================-->
389<div class="doc_subsection">
390<a name="UnladenSwallow">Unladen Swallow</a>
391</div>
392
393<div class="doc_text">
394<p>
395<a href="http://code.google.com/p/unladen-swallow/">Unladen Swallow</a> is a
396branch of <a href="http://python.org/">Python</a> intended to be fully
397compatible and significantly faster. It uses LLVM's optimization passes and JIT
Chris Lattnerb5f6feb2010-03-18 06:52:15 +0000398compiler.
Chris Lattner0e464a92010-03-17 04:02:39 +0000399</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000400</div>
401
402<!--=========================================================================-->
403<div class="doc_subsection">
404<a name="llvm-lua">llvm-lua</a>
405</div>
406
407<div class="doc_text">
408<p>
Chris Lattner0e464a92010-03-17 04:02:39 +0000409Need update.
410<!--
Chris Lattner61358ab2009-10-13 17:48:04 +0000411<a href="http://code.google.com/p/llvm-lua/">LLVM-Lua</a> uses LLVM to add JIT
412and static compiling support to the Lua VM. Lua bytecode is analyzed to
413remove type checks, then LLVM is used to compile the bytecode down to machine
Chris Lattner0e464a92010-03-17 04:02:39 +0000414code.-->
415</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000416</div>
417
418<!--=========================================================================-->
419<div class="doc_subsection">
420<a name="icedtea">IcedTea Java Virtual Machine Implementation</a>
421</div>
422
423<div class="doc_text">
424<p>
Chris Lattner0e464a92010-03-17 04:02:39 +0000425Need update.
426<!--
Chris Lattner61358ab2009-10-13 17:48:04 +0000427<a href="http://icedtea.classpath.org/wiki/Main_Page">IcedTea</a> provides a
428harness to build OpenJDK using only free software build tools and to provide
429replacements for the not-yet free parts of OpenJDK. One of the extensions that
430IcedTea provides is a new JIT compiler named <a
431href="http://icedtea.classpath.org/wiki/ZeroSharkFaq">Shark</a> which uses LLVM
432to provide native code generation without introducing processor-dependent
Chris Lattner0e464a92010-03-17 04:02:39 +0000433code.-->
Chris Lattner61358ab2009-10-13 17:48:04 +0000434</p>
435</div>
436
437
Chris Lattner8d4bbbe2010-03-29 17:50:39 +0000438<!--=========================================================================-->
439<div class="doc_subsection">
440<a name="tce">TTA-based Codesign Environment (TCE)</a>
441</div>
442
443<div class="doc_text">
444<p>
445<a href="http://tce.cs.tut.fi/">TCE</a> is a toolset for designing
446application-specific processors (ASP) based on the Transport triggered
447architecture (TTA). The toolset provides a complete co-design flow from C/C++
448programs down to synthesizable VHDL and parallel program binaries. Processor
449customization points include the register files, function units, supported
450operations, and the interconnection network.</p>
451
452<p>TCE uses llvm-gcc/Clang and LLVM for C/C++ language support, target
453independent optimizations and also for parts of code generation. It generates
454new LLVM-based code generators "on the fly" for the designed TTA processors and
455loads them in to the compiler backend as runtime libraries to avoid per-target
456recompilation of larger parts of the compiler chain.</p>
457
458</div>
Chris Lattner8348b472008-06-08 21:58:17 +0000459
John Criswellf77cdab2010-04-06 14:52:14 +0000460<!--=========================================================================-->
461<div class="doc_subsection">
462<a name="safecode">SAFECode Compiler</a>
463</div>
464
465<div class="doc_text">
466<p>
467<a href="http://safecode.cs.illinois.edu">SAFECode</a> is a memory safe C
468compiler built using LLVM. It takes standard, unannotated C code, analyzes the
469code to ensure that memory accesses and array indexing operations are safe, and
470instruments the code with run-time checks when safety cannot be proven
471statically.
472</p>
473</div>
474
475
Chris Lattner8348b472008-06-08 21:58:17 +0000476<!-- *********************************************************************** -->
477<div class="doc_section">
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000478 <a name="whatsnew">What's New in LLVM 2.7?</a>
Chris Lattner8348b472008-06-08 21:58:17 +0000479</div>
480<!-- *********************************************************************** -->
481
Chris Lattnerf8e0b4e2008-06-08 22:59:35 +0000482<div class="doc_text">
483
Chris Lattner61358ab2009-10-13 17:48:04 +0000484<p>This release includes a huge number of bug fixes, performance tweaks and
Chris Lattnerf6662f92008-10-13 17:57:36 +0000485minor improvements. Some of the major improvements and new features are listed
486in this section.
Chris Lattnerf8e0b4e2008-06-08 22:59:35 +0000487</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000488
Chris Lattnerf8e0b4e2008-06-08 22:59:35 +0000489</div>
490
Chris Lattner8348b472008-06-08 21:58:17 +0000491<!--=========================================================================-->
Chris Lattnerea34f642008-06-08 21:34:41 +0000492<div class="doc_subsection">
Chris Lattner252b83d2008-02-06 18:00:06 +0000493<a name="majorfeatures">Major New Features</a>
494</div>
495
496<div class="doc_text">
497
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000498<p>LLVM 2.7 includes several major new capabilities:</p>
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000499
500<ul>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000501<li>...</li>
Chris Lattner8170c102008-02-10 08:18:42 +0000502</ul>
503
Chris Lattnerc66bfef2010-03-17 04:41:49 +0000504Extensible metadata solid.
505
506Debug info improvements: using metadata instead of llvm.dbg global variables.
507This brings several enhancements including improved compile times.
508
509New instruction selector.
510GHC Haskell ABI/ calling conv support.
511Pre-Alpha support for unions in IR.
512New InlineHint and StackAlignment function attributes
513Code generator MC'ized except for debug info and EH.
514New SCEV AA pass: -scev-aa
515Inliner reuses arrays allocas when inlining multiple callers to reduce stack usage.
516MC encoding and disassembler apis.
517Optimal Edge Profiling?
518Instcombine is now a library, has its own IRBuilder to simplify itself.
519New llvm/Support/Regex.h API. FileCheck now does regex's
Chris Lattnerdc910082010-03-17 06:41:58 +0000520Many subtle pointer invalidation bugs in Callgraph have been fixed and it now uses asserting value handles.
521MC Disassembler (with blog post), MCInstPrinter. Many X86 backend and AsmPrinter simplifications
522Various tools like llc and opt now read either .ll or .bc files as input.
Chris Lattner8e7f1b12010-03-29 18:42:42 +0000523Malloc and free instructions got removed, along with LowerAllocations pass.
Chris Lattnerdc910082010-03-17 06:41:58 +0000524compiler-rt support for ARM.
525completely llvm-gcc NEON support.
526Can transcode from GAS to intel syntax with "llvm-mc foo.s -output-asm-variant=1"
527JIT debug information with GDB 7.0
Chris Lattnerf04bdc52010-03-17 18:15:52 +0000528New CodeGen Level CSE
Chris Lattnerdc910082010-03-17 06:41:58 +0000529CMake can now run tests, what other improvements?
Chris Lattnerf04bdc52010-03-17 18:15:52 +0000530ARM/Thumb using reg scavenging for stack object address materialization (PEI).
Chris Lattnerdc910082010-03-17 06:41:58 +0000531New SSAUpdater and MachineSSAUpdater classes for unstructured ssa updating,
532 changed jump threading, GVN, etc to use it which simplified them and speed
533 them up.
Chris Lattner15a06112010-03-17 06:42:25 +0000534Combiner-AA improvements, why not on by default?
Chris Lattnerf04bdc52010-03-17 18:15:52 +0000535Pre-regalloc tail duplication
Chris Lattner00736fc2010-04-13 06:37:00 +0000536x86 sibcall / tailcall optimization in CCC mode.
Chris Lattner8b5d9c82010-04-16 06:20:22 +0000537New LSR with "full strength reduction" mode. Description?
538Codegen level OptimizeExtsPass pass, takes advantage of x86 subregs.
Chris Lattner00736fc2010-04-13 06:37:00 +0000539Better code size analysis in loop unswitch, inliner code split out to a new
540 CodeMetrics class for reuse.
Chris Lattnerb22060d2010-03-29 18:39:28 +0000541The ARM backend now has good support for ARMv4 backend (tested on StrongARM
542 hardware), previously only supported ARMv4T and newer.
Chris Lattner00736fc2010-04-13 06:37:00 +0000543Half-float support in APFloat
544Indirect branch + address of label (blog post), particularly useful for interpreters.
Chris Lattner8b5d9c82010-04-16 06:20:22 +0000545Many changes to the pass ordering for improved optimization effectiveness.
546BasicAA improved to be less dependent on "type safe" pointers, it can now look
547 through bitcasts more aggressively.
548GVN PHI Translation improvements. blog post: http://blog.llvm.org/2009/12/advanced-topics-in-redundant-load.html
549llvm.objectsize.
550MachineSSAUpdater.h
551PostRA scheduler for X86?
552llvm.dbg.value, not being used by default though, more in 2.8. Many improvements to debug info
553Support for the GCC option -fno-schedule-insns
554non-temporal load/store
555libllvm2.7.so?? configure with --enable-shared
556dbgs() and -debug-buffer-size=N
557New MicroBlaze backend. http://en.wikipedia.org/wiki/MicroBlaze
558XMM subreg modeling for extraction of the low element.
559
Chris Lattnerb22060d2010-03-29 18:39:28 +0000560
Chris Lattner00736fc2010-04-13 06:37:00 +0000561Opt now works conservatively if no target data is set (is this fully working?)
562Target data now has notion of 'native' integer data types which optimizations can use.
563ARM backend generates instructions in unified assembly syntax.
564New Analysis/InstructionSimplify.h interface for simplifying instructions that don't exist.
565Jump threading is now much more aggressive at simplifying correlated
566 conditionals and threading blocks with otherwise complex logic. CondProp pass
567 removed (functionality merged into jump threading).
568X86 and XCore supports returning arbitrary return values, returning too many values is
569 supported by returning through a hidden pointer.
570verbose-asm now produces information about spill slots and loop nests
Chris Lattnerf04bdc52010-03-17 18:15:52 +0000571
Chris Lattnerc66bfef2010-03-17 04:41:49 +0000572
Chris Lattner8b5d9c82010-04-16 06:20:22 +0000573Defaults to RTTI off (smaller code size!), packagers should build with make REQUIRE_RTTI=1.
574AndersAA got removed
575PredSimplify, LoopVR, GVNPRE, RSProfiling (random sampling profiling) got removed.
Chris Lattnerc66bfef2010-03-17 04:41:49 +0000576LLVM command line tools now overwrite their output, before they would only do this with -f.
577DOUT removed, use DEBUG(errs() instead.
578Much stuff converted to use raw_ostream instead of std::ostream.
579TargetAsmInfo renamed to MCAsmInfo
580llvm/ADT/iterator.h gone.
581
Chris Lattnerdc910082010-03-17 06:41:58 +0000582
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000583</div>
584
Chris Lattner84977642007-09-21 03:54:09 +0000585<!--=========================================================================-->
586<div class="doc_subsection">
Chris Lattner917cc712009-03-02 02:37:32 +0000587<a name="coreimprovements">LLVM IR and Core Improvements</a>
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000588</div>
589
590<div class="doc_text">
Chris Lattner61358ab2009-10-13 17:48:04 +0000591<p>LLVM IR has several new features for better support of new targets and that
592expose new optimization opportunities:</p>
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000593
Chris Lattner791f77b2008-06-05 06:25:56 +0000594<ul>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000595<li>...</li>
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000596</ul>
Mikhail Glushenkovea65d7d2008-10-13 02:08:34 +0000597
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000598</div>
599
600<!--=========================================================================-->
601<div class="doc_subsection">
Chris Lattneracce85d2008-02-10 07:46:44 +0000602<a name="optimizer">Optimizer Improvements</a>
603</div>
604
605<div class="doc_text">
606
Chris Lattner61358ab2009-10-13 17:48:04 +0000607<p>In addition to a large array of minor performance tweaks and bug fixes, this
Chris Lattnerf3013872008-10-13 21:50:36 +0000608release includes a few major enhancements and additions to the optimizers:</p>
Chris Lattneracce85d2008-02-10 07:46:44 +0000609
610<ul>
611
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000612<li>...</li>
Chris Lattner917cc712009-03-02 02:37:32 +0000613
Chris Lattner61358ab2009-10-13 17:48:04 +0000614</ul>
Chris Lattner917cc712009-03-02 02:37:32 +0000615
Chris Lattnerf2201912010-03-01 19:29:17 +0000616<p>Also, -anders-aa was removed</p>
617
Chris Lattner61358ab2009-10-13 17:48:04 +0000618</div>
Chris Lattner917cc712009-03-02 02:37:32 +0000619
Chris Lattner917cc712009-03-02 02:37:32 +0000620
Chris Lattner61358ab2009-10-13 17:48:04 +0000621<!--=========================================================================-->
622<div class="doc_subsection">
623<a name="executionengine">Interpreter and JIT Improvements</a>
624</div>
Chris Lattnerf3013872008-10-13 21:50:36 +0000625
Chris Lattner61358ab2009-10-13 17:48:04 +0000626<div class="doc_text">
627
628<ul>
Jeffrey Yasskin01eba392010-01-29 19:10:38 +0000629<li>The JIT now <a
630href="http://llvm.org/viewvc/llvm-project?view=rev&revision=85295">defaults
631to compiling eagerly</a> to avoid a race condition in the lazy JIT.
632Clients that still want the lazy JIT can switch it on by calling
633<tt>ExecutionEngine::DisableLazyCompilation(false)</tt>.</li>
Jeffrey Yasskin40966a72010-02-11 01:07:39 +0000634<li>It is now possible to create more than one JIT instance in the same process.
635These JITs can generate machine code in parallel,
636although <a href="http://llvm.org/docs/ProgrammersManual.html#jitthreading">you
637still have to obey the other threading restrictions</a>.</li>
Chris Lattner0b832202008-06-08 02:45:07 +0000638</ul>
639
640</div>
641
642<!--=========================================================================-->
643<div class="doc_subsection">
Chris Lattner511433e2009-03-02 03:24:11 +0000644<a name="codegen">Target Independent Code Generator Improvements</a>
Chris Lattner0b832202008-06-08 02:45:07 +0000645</div>
646
647<div class="doc_text">
648
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000649<p>We have put a significant amount of work into the code generator
650infrastructure, which allows us to implement more aggressive algorithms and make
651it run faster:</p>
Chris Lattner0b832202008-06-08 02:45:07 +0000652
653<ul>
Chris Lattner511433e2009-03-02 03:24:11 +0000654
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000655<li>...</li>
Chris Lattner84977642007-09-21 03:54:09 +0000656</ul>
Chris Lattner84977642007-09-21 03:54:09 +0000657</div>
658
Chris Lattner917cc712009-03-02 02:37:32 +0000659<!--=========================================================================-->
660<div class="doc_subsection">
661<a name="x86">X86-32 and X86-64 Target Improvements</a>
662</div>
663
664<div class="doc_text">
665<p>New features of the X86 target include:
666</p>
667
668<ul>
Chris Lattner511433e2009-03-02 03:24:11 +0000669
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000670<li>...</li>
Chris Lattner511433e2009-03-02 03:24:11 +0000671
Chris Lattner917cc712009-03-02 02:37:32 +0000672</ul>
673
Chris Lattner917cc712009-03-02 02:37:32 +0000674</div>
Chris Lattner84977642007-09-21 03:54:09 +0000675
676<!--=========================================================================-->
677<div class="doc_subsection">
Chris Lattner11398992009-02-26 07:32:11 +0000678<a name="pic16">PIC16 Target Improvements</a>
679</div>
680
681<div class="doc_text">
682<p>New features of the PIC16 target include:
683</p>
684
685<ul>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000686<li>...</li>
Chris Lattner11398992009-02-26 07:32:11 +0000687</ul>
688
689<p>Things not yet supported:</p>
690
691<ul>
Chris Lattner11398992009-02-26 07:32:11 +0000692<li>Variable arguments.</li>
Chris Lattner511433e2009-03-02 03:24:11 +0000693<li>Interrupts/programs.</li>
Chris Lattner11398992009-02-26 07:32:11 +0000694</ul>
695
696</div>
697
Chris Lattner11398992009-02-26 07:32:11 +0000698<!--=========================================================================-->
699<div class="doc_subsection">
Chris Lattner61358ab2009-10-13 17:48:04 +0000700<a name="ARM">ARM Target Improvements</a>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000701</div>
702
703<div class="doc_text">
Chris Lattner61358ab2009-10-13 17:48:04 +0000704<p>New features of the ARM target include:
705</p>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000706
707<ul>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000708
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000709<li>...</li>
Chris Lattner61358ab2009-10-13 17:48:04 +0000710</ul>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000711
Chris Lattnerc441fb82009-03-01 02:30:21 +0000712
Chris Lattner61358ab2009-10-13 17:48:04 +0000713</div>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000714
Chris Lattner61358ab2009-10-13 17:48:04 +0000715<!--=========================================================================-->
716<div class="doc_subsection">
717<a name="OtherTarget">Other Target Specific Improvements</a>
718</div>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000719
Chris Lattner61358ab2009-10-13 17:48:04 +0000720<div class="doc_text">
721<p>New features of other targets include:
722</p>
723
724<ul>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000725<li>...</li>
Chris Lattner61358ab2009-10-13 17:48:04 +0000726</ul>
727
728</div>
729
730<!--=========================================================================-->
731<div class="doc_subsection">
732<a name="newapis">New Useful APIs</a>
733</div>
734
735<div class="doc_text">
736
737<p>This release includes a number of new APIs that are used internally, which
738 may also be useful for external clients.
739</p>
740
741<ul>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000742<li>...</li>
Chris Lattner61358ab2009-10-13 17:48:04 +0000743</ul>
744
745
746</div>
747
748<!--=========================================================================-->
749<div class="doc_subsection">
750<a name="otherimprovements">Other Improvements and New Features</a>
751</div>
752
753<div class="doc_text">
754<p>Other miscellaneous features include:</p>
755
756<ul>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000757<li>...</li>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000758</ul>
759
760</div>
761
Chris Lattner77d29b12008-06-05 08:02:49 +0000762
763<!--=========================================================================-->
764<div class="doc_subsection">
Chris Lattnerf6662f92008-10-13 17:57:36 +0000765<a name="changes">Major Changes and Removed Features</a>
766</div>
767
768<div class="doc_text">
769
Chris Lattnereeb4da02008-10-13 22:06:31 +0000770<p>If you're already an LLVM user or developer with out-of-tree changes based
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000771on LLVM 2.6, this section lists some "gotchas" that you may run into upgrading
Chris Lattnereeb4da02008-10-13 22:06:31 +0000772from the previous release.</p>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000773
774<ul>
Jeffrey Yasskinbc83d062010-02-09 23:03:44 +0000775<li>The LLVM interpreter now defaults to <em>not</em> using <tt>libffi</tt> even
776if you have it installed. This makes it more likely that an LLVM built on one
777system will work when copied to a similar system. To use <tt>libffi</tt>,
778configure with <tt>--enable-libffi</tt>.
779</li>
Chris Lattnereeb4da02008-10-13 22:06:31 +0000780</ul>
781
782
783<p>In addition, many APIs have changed in this release. Some of the major LLVM
784API changes are:</p>
785
786<ul>
Jeffrey Yasskin4fcd6072010-01-28 01:41:20 +0000787<li><tt>ModuleProvider</tt> has been <a
788href="http://llvm.org/viewvc/llvm-project?view=rev&revision=94686">removed</a>
789and its methods moved to <tt>Module</tt> and <tt>GlobalValue</tt>.
790Most clients can remove uses of <tt>ExistingModuleProvider</tt>,
791replace <tt>getBitcodeModuleProvider</tt> with
792<tt>getLazyBitcodeModule</tt>, and pass their <tt>Module</tt> to
793functions that used to accept <tt>ModuleProvider</tt>. Clients who
794wrote their own <tt>ModuleProvider</tt>s will need to derive from
795<tt>GVMaterializer</tt> instead and use
796<tt>Module::setMaterializer</tt> to attach it to a
797<tt>Module</tt>.</li>
798
799<li><tt>GhostLinkage</tt> has given up the ghost.
800<tt>GlobalValue</tt>s that have not yet been read from their backing
801storage have the same linkage they will have after being read in.
802Clients must replace calls to
803<tt>GlobalValue::hasNotBeenReadFromBitcode</tt> with
804<tt>GlobalValue::isMaterializable</tt>.</li>
Daniel Dunbar4acdede2010-02-10 04:09:52 +0000805
806<li>FIXME: Debug info has been totally redone. Add pointers to new APIs. Substantial caveats about compatibility of .ll and .bc files.</li>
807
Daniel Dunbarca1c8162010-02-14 01:47:19 +0000808<li>The <tt>llvm/Support/DataTypes.h</tt> header has moved
809to <tt>llvm/System/DataTypes.h</tt>.</li>
810
Duncan Sands411432d2010-02-17 17:20:17 +0000811<li>The <tt>isInteger</tt>, <tt>isIntOrIntVector</tt>, <tt>isFloatingPoint</tt>,
812<tt>isFPOrFPVector</tt> and <tt>isFPOrFPVector</tt> methods have been renamed
813<tt>isIntegerTy</tt>, <tt>isIntOrIntVectorTy</tt>, <tt>isFloatingPointTy</tt>,
814<tt>isFPOrFPVectorTy</tt> and <tt>isFPOrFPVectorTy</tt> respectively.</li>
Devang Patelb34dd132008-10-14 20:03:43 +0000815</ul>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000816
Chris Lattnerf6662f92008-10-13 17:57:36 +0000817</div>
818
819
820
Chris Lattner19092612003-10-02 16:38:05 +0000821<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000822<div class="doc_section">
823 <a name="portability">Portability and Supported Platforms</a>
824</div>
Chris Lattner19092612003-10-02 16:38:05 +0000825<!-- *********************************************************************** -->
826
Misha Brukman500bc302003-11-22 00:38:41 +0000827<div class="doc_text">
828
John Criswell0b5b5e92004-12-08 20:35:47 +0000829<p>LLVM is known to work on the following platforms:</p>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000830
831<ul>
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000832<li>Intel and AMD machines (IA32, X86-64, AMD64, EMT-64) running Red Hat
Chris Lattner61358ab2009-10-13 17:48:04 +0000833 Linux, Fedora Core, FreeBSD and AuroraUX (and probably other unix-like
834 systems).</li>
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000835<li>PowerPC and X86-based Mac OS X systems, running 10.3 and above in 32-bit
Chris Lattner61358ab2009-10-13 17:48:04 +0000836 and 64-bit modes.</li>
Chris Lattner252b83d2008-02-06 18:00:06 +0000837<li>Intel and AMD machines running on Win32 using MinGW libraries (native).</li>
Chris Lattner57a460e2007-05-23 04:39:32 +0000838<li>Intel and AMD machines running on Win32 with the Cygwin libraries (limited
839 support is available for native builds with Visual C++).</li>
Chris Lattner7e23d6e2009-10-16 16:30:58 +0000840<li>Sun x86 and AMD64 machines running Solaris 10, OpenSolaris 0906.</li>
John Criswell9321fa82005-05-13 20:28:15 +0000841<li>Alpha-based machines running Debian GNU/Linux.</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000842</ul>
843
Chris Lattnerbc5786b2008-06-05 06:57:39 +0000844<p>The core LLVM infrastructure uses GNU autoconf to adapt itself
Brian Gaekeb0fd7612004-05-09 05:28:35 +0000845to the machine and operating system on which it is built. However, minor
846porting may be required to get LLVM to work on new platforms. We welcome your
847portability patches and reports of successful builds or error messages.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000848
Misha Brukman500bc302003-11-22 00:38:41 +0000849</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000850
851<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000852<div class="doc_section">
853 <a name="knownproblems">Known Problems</a>
854</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000855<!-- *********************************************************************** -->
856
Misha Brukman500bc302003-11-22 00:38:41 +0000857<div class="doc_text">
858
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000859<p>This section contains significant known problems with the LLVM system,
Chris Lattnere18b32e2008-11-10 05:40:34 +0000860listed by component. If you run into a problem, please check the <a
Chris Lattnerc463b272005-10-29 07:07:09 +0000861href="http://llvm.org/bugs/">LLVM bug database</a> and submit a bug if
Chris Lattner5eccca42003-12-12 21:22:16 +0000862there isn't already one.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000863
Chris Lattner477a1fd2010-03-17 17:25:49 +0000864<ul>
Chris Lattner61358ab2009-10-13 17:48:04 +0000865<li>LLVM will not correctly compile on Solaris and/or OpenSolaris
866using the stock GCC 3.x.x series 'out the box',
Chris Lattner554ee4a2009-11-03 21:50:09 +0000867See: <a href="GettingStarted.html#brokengcc">Broken versions of GCC and other tools</a>.
Chris Lattner61358ab2009-10-13 17:48:04 +0000868However, A <a href="http://pkg.auroraux.org/GCC">Modern GCC Build</a>
869for x86/x86-64 has been made available from the third party AuroraUX Project
870that has been meticulously tested for bootstrapping LLVM &amp; Clang.</li>
871</ul>
872
Misha Brukman500bc302003-11-22 00:38:41 +0000873</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000874
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000875<!-- ======================================================================= -->
876<div class="doc_subsection">
877 <a name="experimental">Experimental features included with this release</a>
878</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000879
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000880<div class="doc_text">
881
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000882<p>The following components of this LLVM release are either untested, known to
883be broken or unreliable, or are in early development. These components should
884not be relied on, and bugs should not be filed against them, but they may be
885useful to some people. In particular, if you would like to work on one of these
Chris Lattner2b659ef2008-02-12 06:29:45 +0000886components, please contact us on the <a
887href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev list</a>.</p>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000888
889<ul>
Wesley Peck7c4a1212010-03-18 14:31:30 +0000890<li>The MSIL, Alpha, SPU, MIPS, PIC16, Blackfin, MSP430, SystemZ and MicroBlaze
891 backends are experimental.</li>
Bill Wendling99dac472009-03-02 07:54:14 +0000892<li>The <tt>llc</tt> "<tt>-filetype=asm</tt>" (the default) is the only
Chris Lattnerc66bfef2010-03-17 04:41:49 +0000893 supported value for this option. The MachO writer is experimental, and
894 works much better in mainline SVN.</li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000895</ul>
896
897</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000898
Misha Brukman500bc302003-11-22 00:38:41 +0000899<!-- ======================================================================= -->
900<div class="doc_subsection">
Chris Lattner26299222006-11-18 07:51:14 +0000901 <a name="x86-be">Known problems with the X86 back-end</a>
John Criswellc0c186d2005-11-08 21:11:33 +0000902</div>
903
904<div class="doc_text">
905
906<ul>
Anton Korobeynikova6094be2008-06-08 10:24:13 +0000907 <li>The X86 backend does not yet support
908 all <a href="http://llvm.org/PR879">inline assembly that uses the X86
909 floating point stack</a>. It supports the 'f' and 't' constraints, but not
910 'u'.</li>
Chris Lattnere6e1b352008-06-08 21:19:07 +0000911 <li>The X86 backend generates inefficient floating point code when configured
912 to generate code for systems that don't have SSE2.</li>
Duncan Sands47eff2b2008-06-08 19:38:43 +0000913 <li>Win64 code generation wasn't widely tested. Everything should work, but we
John Criswell524a5dd2009-03-02 15:28:15 +0000914 expect small issues to happen. Also, llvm-gcc cannot build the mingw64
915 runtime currently due
Anton Korobeynikova6094be2008-06-08 10:24:13 +0000916 to <a href="http://llvm.org/PR2255">several</a>
John Criswell524a5dd2009-03-02 15:28:15 +0000917 <a href="http://llvm.org/PR2257">bugs</a> and due to lack of support for
918 the
919 'u' inline assembly constraint and for X87 floating point inline assembly.</li>
Dan Gohman8207ba92008-06-08 23:05:11 +0000920 <li>The X86-64 backend does not yet support the LLVM IR instruction
Chris Lattner917cc712009-03-02 02:37:32 +0000921 <tt>va_arg</tt>. Currently, the llvm-gcc and front-ends support variadic
Dan Gohman8207ba92008-06-08 23:05:11 +0000922 argument constructs on X86-64 by lowering them manually.</li>
Chris Lattner26299222006-11-18 07:51:14 +0000923</ul>
924
925</div>
926
927<!-- ======================================================================= -->
928<div class="doc_subsection">
929 <a name="ppc-be">Known problems with the PowerPC back-end</a>
930</div>
931
932<div class="doc_text">
933
934<ul>
Nicolas Geoffraye4285dc2007-05-15 09:21:28 +0000935<li>The Linux PPC32/ABI support needs testing for the interpreter and static
Chris Lattner57a460e2007-05-23 04:39:32 +0000936compilation, and lacks support for debug information.</li>
Chris Lattner26299222006-11-18 07:51:14 +0000937</ul>
938
939</div>
940
941<!-- ======================================================================= -->
942<div class="doc_subsection">
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000943 <a name="arm-be">Known problems with the ARM back-end</a>
944</div>
945
946<div class="doc_text">
947
948<ul>
Chris Lattner61358ab2009-10-13 17:48:04 +0000949<li>Support for the Advanced SIMD (Neon) instruction set is still incomplete
950and not well tested. Some features may not work at all, and the code quality
951may be poor in some cases.</li>
Chris Lattner57a460e2007-05-23 04:39:32 +0000952<li>Thumb mode works only on ARMv6 or higher processors. On sub-ARMv6
Duncan Sandsc90d68b2007-09-26 15:59:54 +0000953processors, thumb programs can crash or produce wrong
Chris Lattner57a460e2007-05-23 04:39:32 +0000954results (<a href="http://llvm.org/PR1388">PR1388</a>).</li>
John Criswell524a5dd2009-03-02 15:28:15 +0000955<li>Compilation for ARM Linux OABI (old ABI) is supported but not fully tested.
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000956</li>
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000957</ul>
958
959</div>
960
961<!-- ======================================================================= -->
962<div class="doc_subsection">
Chris Lattner26299222006-11-18 07:51:14 +0000963 <a name="sparc-be">Known problems with the SPARC back-end</a>
964</div>
965
966<div class="doc_text">
967
968<ul>
John Criswell524a5dd2009-03-02 15:28:15 +0000969<li>The SPARC backend only supports the 32-bit SPARC ABI (-m32); it does not
Chris Lattner26299222006-11-18 07:51:14 +0000970 support the 64-bit SPARC ABI (-m64).</li>
971</ul>
972
973</div>
974
975<!-- ======================================================================= -->
976<div class="doc_subsection">
Bruno Cardoso Lopesb7e1a4f2008-10-25 14:56:26 +0000977 <a name="mips-be">Known problems with the MIPS back-end</a>
978</div>
979
980<div class="doc_text">
981
982<ul>
Bruno Cardoso Lopesb7e1a4f2008-10-25 14:56:26 +0000983<li>64-bit MIPS targets are not supported yet.</li>
984</ul>
985
986</div>
987
988<!-- ======================================================================= -->
989<div class="doc_subsection">
Chris Lattner26299222006-11-18 07:51:14 +0000990 <a name="alpha-be">Known problems with the Alpha back-end</a>
991</div>
992
993<div class="doc_text">
994
995<ul>
996
997<li>On 21164s, some rare FP arithmetic sequences which may trap do not have the
998appropriate nops inserted to ensure restartability.</li>
999
John Criswellc0c186d2005-11-08 21:11:33 +00001000</ul>
1001</div>
1002
Chris Lattner26299222006-11-18 07:51:14 +00001003<!-- ======================================================================= -->
1004<div class="doc_subsection">
Chris Lattnerf3e5bc62007-05-14 06:56:09 +00001005 <a name="c-be">Known problems with the C back-end</a>
Chris Lattner26299222006-11-18 07:51:14 +00001006</div>
1007
1008<div class="doc_text">
1009
1010<ul>
Chris Lattner5733b272008-06-05 06:35:40 +00001011<li><a href="http://llvm.org/PR802">The C backend has only basic support for
1012 inline assembly code</a>.</li>
Chris Lattner725a0d82007-09-26 06:01:35 +00001013<li><a href="http://llvm.org/PR1658">The C backend violates the ABI of common
1014 C++ programs</a>, preventing intermixing between C++ compiled by the CBE and
Gabor Greif4906abe2009-03-02 12:02:51 +00001015 C++ code compiled with <tt>llc</tt> or native compilers.</li>
Duncan Sandsf74c0cc2008-02-10 13:40:55 +00001016<li>The C backend does not support all exception handling constructs.</li>
Duncan Sands50723a92009-02-25 11:51:54 +00001017<li>The C backend does not support arbitrary precision integers.</li>
Chris Lattner26299222006-11-18 07:51:14 +00001018</ul>
1019
1020</div>
John Criswellc0c186d2005-11-08 21:11:33 +00001021
Misha Brukman500bc302003-11-22 00:38:41 +00001022
1023<!-- ======================================================================= -->
1024<div class="doc_subsection">
Chris Lattnerc66bfef2010-03-17 04:41:49 +00001025 <a name="c-fe">Known problems with the llvm-gcc C and C++ front-end</a>
Misha Brukman500bc302003-11-22 00:38:41 +00001026</div>
Chris Lattner47588f92003-10-02 05:07:23 +00001027
Misha Brukman500bc302003-11-22 00:38:41 +00001028<div class="doc_text">
Chris Lattnerc5d658a2006-03-03 00:34:26 +00001029
Chris Lattner5733b272008-06-05 06:35:40 +00001030<p>The only major language feature of GCC not supported by llvm-gcc is
1031 the <tt>__builtin_apply</tt> family of builtins. However, some extensions
1032 are only supported on some targets. For example, trampolines are only
Duncan Sands27aff872008-06-08 20:18:35 +00001033 supported on some targets (these are used when you take the address of a
1034 nested function).</p>
Misha Brukman500bc302003-11-22 00:38:41 +00001035
Chris Lattner5733b272008-06-05 06:35:40 +00001036<p>If you run into GCC extensions which are not supported, please let us know.
1037</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +00001038
Misha Brukman500bc302003-11-22 00:38:41 +00001039</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +00001040
Misha Brukman500bc302003-11-22 00:38:41 +00001041<!-- ======================================================================= -->
1042<div class="doc_subsection">
Chris Lattner1eb4df62008-10-30 03:58:13 +00001043 <a name="fortran-fe">Known problems with the llvm-gcc Fortran front-end</a>
1044</div>
1045
1046<div class="doc_text">
Gabor Greifba10fe02008-11-04 21:50:59 +00001047<ul>
Chris Lattner1eb4df62008-10-30 03:58:13 +00001048<li>Fortran support generally works, but there are still several unresolved bugs
Chris Lattner61358ab2009-10-13 17:48:04 +00001049 in <a href="http://llvm.org/bugs/">Bugzilla</a>. Please see the
1050 tools/gfortran component for details.</li>
Gabor Greifba10fe02008-11-04 21:50:59 +00001051</ul>
Chris Lattner1eb4df62008-10-30 03:58:13 +00001052</div>
Misha Brukman500bc302003-11-22 00:38:41 +00001053
Chris Lattner2b659ef2008-02-12 06:29:45 +00001054<!-- ======================================================================= -->
1055<div class="doc_subsection">
Chris Lattner5733b272008-06-05 06:35:40 +00001056 <a name="ada-fe">Known problems with the llvm-gcc Ada front-end</a>
Chris Lattner2b659ef2008-02-12 06:29:45 +00001057</div>
1058
1059<div class="doc_text">
John Criswell524a5dd2009-03-02 15:28:15 +00001060The llvm-gcc 4.2 Ada compiler works fairly well; however, this is not a mature
1061technology, and problems should be expected.
Chris Lattner2b659ef2008-02-12 06:29:45 +00001062<ul>
Duncan Sands27aff872008-06-08 20:18:35 +00001063<li>The Ada front-end currently only builds on X86-32. This is mainly due
John Criswell524a5dd2009-03-02 15:28:15 +00001064to lack of trampoline support (pointers to nested functions) on other platforms.
1065However, it <a href="http://llvm.org/PR2006">also fails to build on X86-64</a>
Chris Lattner2b659ef2008-02-12 06:29:45 +00001066which does support trampolines.</li>
1067<li>The Ada front-end <a href="http://llvm.org/PR2007">fails to bootstrap</a>.
Duncan Sands326a4982009-02-25 11:59:06 +00001068This is due to lack of LLVM support for <tt>setjmp</tt>/<tt>longjmp</tt> style
1069exception handling, which is used internally by the compiler.
Chris Lattner61358ab2009-10-13 17:48:04 +00001070Workaround: configure with <tt>--disable-bootstrap</tt>.</li>
Duncan Sands978bcee2008-10-13 17:27:23 +00001071<li>The c380004, <a href="http://llvm.org/PR2010">c393010</a>
1072and <a href="http://llvm.org/PR2421">cxg2021</a> ACATS tests fail
Duncan Sands326a4982009-02-25 11:59:06 +00001073(c380004 also fails with gcc-4.2 mainline).
1074If the compiler is built with checks disabled then <a href="http://llvm.org/PR2010">c393010</a>
1075causes the compiler to go into an infinite loop, using up all system memory.</li>
Duncan Sandsdd3e6722009-03-02 16:35:57 +00001076<li>Some GCC specific Ada tests continue to crash the compiler.</li>
Chris Lattner61358ab2009-10-13 17:48:04 +00001077<li>The <tt>-E</tt> binder option (exception backtraces)
Chris Lattner2b659ef2008-02-12 06:29:45 +00001078<a href="http://llvm.org/PR1982">does not work</a> and will result in programs
Chris Lattner61358ab2009-10-13 17:48:04 +00001079crashing if an exception is raised. Workaround: do not use <tt>-E</tt>.</li>
Chris Lattner2b659ef2008-02-12 06:29:45 +00001080<li>Only discrete types <a href="http://llvm.org/PR1981">are allowed to start
1081or finish at a non-byte offset</a> in a record. Workaround: do not pack records
1082or use representation clauses that result in a field of a non-discrete type
1083starting or finishing in the middle of a byte.</li>
Chris Lattnere6e1b352008-06-08 21:19:07 +00001084<li>The <tt>lli</tt> interpreter <a href="http://llvm.org/PR2009">considers
1085'main' as generated by the Ada binder to be invalid</a>.
1086Workaround: hand edit the file to use pointers for <tt>argv</tt> and
1087<tt>envp</tt> rather than integers.</li>
1088<li>The <tt>-fstack-check</tt> option <a href="http://llvm.org/PR2008">is
1089ignored</a>.</li>
Chris Lattner2b659ef2008-02-12 06:29:45 +00001090</ul>
1091</div>
1092
Chris Lattner79c3fe12003-10-02 04:57:28 +00001093<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +00001094<div class="doc_section">
1095 <a name="additionalinfo">Additional Information</a>
1096</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +00001097<!-- *********************************************************************** -->
1098
Misha Brukman500bc302003-11-22 00:38:41 +00001099<div class="doc_text">
1100
Chris Lattner416db102005-05-16 17:13:10 +00001101<p>A wide variety of additional information is available on the <a
Chris Lattnerb4b0ce72007-05-18 00:44:29 +00001102href="http://llvm.org">LLVM web page</a>, in particular in the <a
1103href="http://llvm.org/docs/">documentation</a> section. The web page also
Reid Spencer669ed452007-07-09 08:04:31 +00001104contains versions of the API documentation which is up-to-date with the
1105Subversion version of the source code.
Misha Brukman109d9e82005-03-30 19:14:24 +00001106You can access versions of these documents specific to this release by going
1107into the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +00001108
Misha Brukman500bc302003-11-22 00:38:41 +00001109<p>If you have any questions or comments about LLVM, please feel free to contact
Chris Lattnerc463b272005-10-29 07:07:09 +00001110us via the <a href="http://llvm.org/docs/#maillist"> mailing
Chris Lattner5eccca42003-12-12 21:22:16 +00001111lists</a>.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +00001112
Misha Brukman500bc302003-11-22 00:38:41 +00001113</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +00001114
1115<!-- *********************************************************************** -->
Chris Lattner79c3fe12003-10-02 04:57:28 +00001116
Misha Brukman500bc302003-11-22 00:38:41 +00001117<hr>
Misha Brukman2061e892003-11-22 01:23:39 +00001118<address>
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Misha Brukman2061e892003-11-22 01:23:39 +00001123
Chris Lattnerb4b0ce72007-05-18 00:44:29 +00001124 <a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br>
Misha Brukman500bc302003-11-22 00:38:41 +00001125 Last modified: $Date$
Misha Brukman2061e892003-11-22 01:23:39 +00001126</address>
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