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gerrit-public.fairphone.software / toolchain / llvm-project / ec27c49d6c45cea1614a0d5f93a49b6b4524fdb5 / . / llvm / docs / ReleaseNotes.html
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Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
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3<html>
4<head>
Reid Spencere4190fa2004-11-18 18:38:58 +0000[diff] [blame]5 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]6 <link rel="stylesheet" href="llvm.css" type="text/css">
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]7 <title>LLVM 2.7 Release Notes</title>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]8</head>
9<body>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]10
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]11<div class="doc_title">LLVM 2.7 Release Notes</div>
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]12
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]13<ol>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]14 <li><a href="#intro">Introduction</a></li>
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]15 <li><a href="#subproj">Sub-project Status Update</a></li>
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]16 <li><a href="#externalproj">External Projects Using LLVM 2.7</a></li>
17 <li><a href="#whatsnew">What's New in LLVM 2.7?</a></li>
Chris Lattner77a51732004-04-30 22:17:12 +0000[diff] [blame]18 <li><a href="GettingStarted.html">Installation Instructions</a></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]19 <li><a href="#portability">Portability and Supported Platforms</a></li>
Dan Gohmanad888912008-10-14 16:23:02 +0000[diff] [blame]20 <li><a href="#knownproblems">Known Problems</a></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]21 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]22</ol>
23
Chris Lattner020e1fc2004-05-23 21:07:27 +0000[diff] [blame]24<div class="doc_author">
Dan Gohmanad888912008-10-14 16:23:02 +0000[diff] [blame]25 <p>Written by the <a href="http://llvm.org">LLVM Team</a></p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]26</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]27
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]28<h1 style="color:red">These are in-progress notes for the upcoming LLVM 2.7
29release.<br>
30You may prefer the
31<a href="http://llvm.org/releases/2.6/docs/ReleaseNotes.html">LLVM 2.6
32Release Notes</a>.</h1>
33
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]34<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]35<div class="doc_section">
36 <a name="intro">Introduction</a>
37</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]38<!-- *********************************************************************** -->
39
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]40<div class="doc_text">
41
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]42<p>This document contains the release notes for the LLVM Compiler
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]43Infrastructure, release 2.7. Here we describe the status of LLVM, including
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]44major improvements from the previous release and significant known problems.
Mikhail Glushenkov25422542009-03-01 18:09:47 +0000[diff] [blame]45All LLVM releases may be downloaded from the <a
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]46href="http://llvm.org/releases/">LLVM releases web site</a>.</p>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]47
Chris Lattnerb5bb5972004-12-07 08:04:13 +0000[diff] [blame]48<p>For more information about LLVM, including information about the latest
Chris Lattnera69595e2005-10-29 07:07:09 +0000[diff] [blame]49release, please check out the <a href="http://llvm.org/">main LLVM
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]50web site</a>. If you have questions or comments, the <a
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]51href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM Developer's Mailing
52List</a> is a good place to send them.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]53
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]54<p>Note that if you are reading this file from a Subversion checkout or the
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]55main LLVM web page, this document applies to the <i>next</i> release, not the
Gabor Greif355f81c2008-10-14 11:00:32 +0000[diff] [blame]56current one. To see the release notes for a specific release, please see the
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]57<a href="http://llvm.org/releases/">releases page</a>.</p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]58
59</div>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]60
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]61
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]62<!--
63Almost dead code.
64 include/llvm/Analysis/LiveValues.h => Dan
65 lib/Transforms/IPO/MergeFunctions.cpp => consider for 2.8.
66 llvm/Analysis/PointerTracking.h => Edwin wants this, consider for 2.8.
Chris Lattner2bfa1672010-01-09 22:30:40 +0000[diff] [blame]67 ABCD, SCCVN, GEPSplitterPass
Chris Lattner89ea59d2010-01-16 21:25:13 +0000[diff] [blame]68 MSIL backend?
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]69-->
70
71
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]72<!-- Features that need text if they're finished for 2.7:
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]73 gcc plugin.
74 strong phi elim
75 variable debug info for optimized code
Chris Lattner53e06f92009-02-26 22:33:38 +0000[diff] [blame]76 postalloc scheduler: anti dependence breaking, hazard recognizer?
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]77 metadata
78 loop dependence analysis
79 ELF Writer? How stable?
80 <li>PostRA scheduler improvements, ARM adoption (David Goodwin).</li>
81 2.7 supports the GDB 7.0 jit interfaces for debug info.
82 2.7 eliminates ADT/iterator.h
Chris Lattner2b8a52e2008-02-10 07:46:44 +0000[diff] [blame]83 -->
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]84
Chris Lattnerc4d68542008-10-12 19:47:48 +0000[diff] [blame]85 <!-- for announcement email:
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]86 Logo web page.
87 llvm devmtg
88 compiler_rt
89 KLEE web page at klee.llvm.org
90 Many new papers added to /pubs/
91 Mention gcc plugin.
92
Chris Lattnerd02da042009-02-25 06:34:50 +0000[diff] [blame]93 -->
Chris Lattner2b8a52e2008-02-10 07:46:44 +0000[diff] [blame]94
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]95<!-- *********************************************************************** -->
96<div class="doc_section">
97 <a name="subproj">Sub-project Status Update</a>
Chris Lattner625a3d82008-06-08 21:34:41 +0000[diff] [blame]98</div>
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]99<!-- *********************************************************************** -->
Chris Lattner625a3d82008-06-08 21:34:41 +0000[diff] [blame]100
101<div class="doc_text">
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]102<p>
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]103The LLVM 2.7 distribution currently consists of code from the core LLVM
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]104repository (which roughly includes the LLVM optimizers, code generators
105and supporting tools), the Clang repository and the llvm-gcc repository. In
106addition to this code, the LLVM Project includes other sub-projects that are in
107development. Here we include updates on these subprojects.
Bill Wendlingf170d2e2009-03-02 04:28:57 +0000[diff] [blame]108</p>
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]109
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]110</div>
111
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]112
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]113<!--=========================================================================-->
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]114<div class="doc_subsection">
Chris Lattner44c09cd2008-10-13 18:11:54 +0000[diff] [blame]115<a name="clang">Clang: C/C++/Objective-C Frontend Toolkit</a>
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]116</div>
117
118<div class="doc_text">
119
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]120<p>The <a href="http://clang.llvm.org/">Clang project</a> is ...</p>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]121
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]122<p>In the LLVM 2.7 time-frame, the Clang team has made many improvements:</p>
Bill Wendlingef362462008-10-27 09:27:33 +0000[diff] [blame]123
Daniel Dunbarc11b40f2008-10-14 23:25:09 +0000[diff] [blame]124<ul>
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]125<li>...</li>
Bill Wendling87adbe42009-03-02 04:28:18 +0000[diff] [blame]126</ul>
Chris Lattner44c09cd2008-10-13 18:11:54 +0000[diff] [blame]127</div>
128
129<!--=========================================================================-->
130<div class="doc_subsection">
131<a name="clangsa">Clang Static Analyzer</a>
132</div>
133
134<div class="doc_text">
135
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]136<p>Previously announced in the 2.4, 2.5, and 2.6 LLVM releases, the Clang project also
Ted Kremenekc11fae82009-02-27 07:01:32 +0000[diff] [blame]137includes an early stage static source code analysis tool for <a
138href="http://clang.llvm.org/StaticAnalysis.html">automatically finding bugs</a>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]139in C and Objective-C programs. The tool performs checks to find
Ted Kremenekc11fae82009-02-27 07:01:32 +0000[diff] [blame]140bugs that occur on a specific path within a program.</p>
Chris Lattnerbcffa5a2008-10-14 00:52:49 +0000[diff] [blame]141
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]142<p>In the LLVM 2.7 time-frame, the analyzer core has ...</p>
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]143
144</div>
145
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]146<!--=========================================================================-->
147<div class="doc_subsection">
Nicolas Geoffraye5ec9322008-10-14 19:23:04 +0000[diff] [blame]148<a name="vmkit">VMKit: JVM/CLI Virtual Machine Implementation</a>
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]149</div>
150
151<div class="doc_text">
152<p>
Nicolas Geoffraye5ec9322008-10-14 19:23:04 +0000[diff] [blame]153The <a href="http://vmkit.llvm.org/">VMKit project</a> is an implementation of
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]154a JVM and a CLI Virtual Machine (Microsoft .NET is an
155implementation of the CLI) using LLVM for static and just-in-time
156compilation.</p>
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]157
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]158<p>
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]159VMKit version ?? builds with LLVM 2.7 and you can find it on its
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]160<a href="http://vmkit.llvm.org/releases/">web page</a>. The release includes
Nicolas Geoffray54efd492008-10-15 20:25:04 +0000[diff] [blame]161bug fixes, cleanup and new features. The major changes are:</p>
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]162
Nicolas Geoffraye5ec9322008-10-14 19:23:04 +0000[diff] [blame]163<ul>
164
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]165<li>...</li>
Nicolas Geoffraye5ec9322008-10-14 19:23:04 +0000[diff] [blame]166
167</ul>
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]168</div>
169
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]170
171<!--=========================================================================-->
172<div class="doc_subsection">
173<a name="compiler-rt">compiler-rt: Compiler Runtime Library</a>
174</div>
175
176<div class="doc_text">
177<p>
178The new LLVM <a href="http://compiler-rt.llvm.org/">compiler-rt project</a>
179is a simple library that provides an implementation of the low-level
180target-specific hooks required by code generation and other runtime components.
181For example, when compiling for a 32-bit target, converting a double to a 64-bit
182unsigned integer is compiled into a runtime call to the "__fixunsdfdi"
183function. The compiler-rt library provides highly optimized implementations of
184this and other low-level routines (some are 3x faster than the equivalent
185libgcc routines).</p>
186
187<p>
188All of the code in the compiler-rt project is available under the standard LLVM
189License, a "BSD-style" license.</p>
190
191</div>
192
193<!--=========================================================================-->
194<div class="doc_subsection">
195<a name="klee">KLEE: Symbolic Execution and Automatic Test Case Generator</a>
196</div>
197
198<div class="doc_text">
199<p>
200The new LLVM <a href="http://klee.llvm.org/">KLEE project</a> is a symbolic
201execution framework for programs in LLVM bitcode form. KLEE tries to
202symbolically evaluate "all" paths through the application and records state
203transitions that lead to fault states. This allows it to construct testcases
204that lead to faults and can even be used to verify algorithms. For more
205details, please see the <a
206href="http://llvm.org/pubs/2008-12-OSDI-KLEE.html">OSDI 2008 paper</a> about
207KLEE.</p>
208
209</div>
210
211<!--=========================================================================-->
212<div class="doc_subsection">
213<a name="dragonegg">DragonEgg: GCC-4.5 as an LLVM frontend</a>
214</div>
215
216<div class="doc_text">
217<p>
218The goal of <a href="http://dragonegg.llvm.org/">DragonEgg</a> is to make
219gcc-4.5 act like llvm-gcc without requiring any gcc modifications whatsoever.
Duncan Sands100d0e3c2009-10-15 08:17:44 +0000[diff] [blame]220<a href="http://dragonegg.llvm.org/">DragonEgg</a> is a shared library (dragonegg.so)
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]221that is loaded by gcc at runtime. It ...
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]222</p>
223
224</div>
225
226
227<!--=========================================================================-->
228<div class="doc_subsection">
229<a name="mc">llvm-mc: Machine Code Toolkit</a>
230</div>
231
232<div class="doc_text">
233<p>
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]234The LLVM Machine Code (MC) Toolkit project is ...
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]235</p>
236
237</div>
238
239
Chris Lattner53e06f92009-02-26 22:33:38 +0000[diff] [blame]240<!-- *********************************************************************** -->
241<div class="doc_section">
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]242 <a name="externalproj">External Open Source Projects Using LLVM 2.7</a>
Chris Lattner53e06f92009-02-26 22:33:38 +0000[diff] [blame]243</div>
244<!-- *********************************************************************** -->
245
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]246<div class="doc_text">
247
248<p>An exciting aspect of LLVM is that it is used as an enabling technology for
249 a lot of other language and tools projects. This section lists some of the
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]250 projects that have already been updated to work with LLVM 2.7.</p>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]251</div>
252
253
254<!--=========================================================================-->
255<div class="doc_subsection">
256<a name="Rubinius">Rubinius</a>
257</div>
258
259<div class="doc_text">
260<p><a href="http://github.com/evanphx/rubinius">Rubinius</a> is an environment
261for running Ruby code which strives to write as much of the core class
262implementation in Ruby as possible. Combined with a bytecode interpreting VM, it
263uses LLVM to optimize and compile ruby code down to machine code. Techniques
264such as type feedback, method inlining, and uncommon traps are all used to
265remove dynamism from ruby execution and increase performance.</p>
266
267<p>Since LLVM 2.5, Rubinius has made several major leaps forward, implementing
268a counter based JIT, type feedback and speculative method inlining.
269</p>
270
271</div>
272
273<!--=========================================================================-->
274<div class="doc_subsection">
275<a name="macruby">MacRuby</a>
276</div>
277
278<div class="doc_text">
279
280<p>
281<a href="http://macruby.org">MacRuby</a> is an implementation of Ruby on top of
282core Mac OS X technologies, such as the Objective-C common runtime and garbage
283collector and the CoreFoundation framework. It is principally developed by
284Apple and aims at enabling the creation of full-fledged Mac OS X applications.
285</p>
286
287<p>
288MacRuby uses LLVM for optimization passes, JIT and AOT compilation of Ruby
289expressions. It also uses zero-cost DWARF exceptions to implement Ruby exception
290handling.</p>
291
292</div>
293
294
Chris Lattner53e06f92009-02-26 22:33:38 +0000[diff] [blame]295<!--=========================================================================-->
296<div class="doc_subsection">
297<a name="pure">Pure</a>
298</div>
299
300<div class="doc_text">
301<p>
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]302<a href="http://pure-lang.googlecode.com/">Pure</a>
303is an algebraic/functional programming language based on term rewriting.
Chris Lattner53e06f92009-02-26 22:33:38 +0000[diff] [blame]304Programs are collections of equations which are used to evaluate expressions in
305a symbolic fashion. Pure offers dynamic typing, eager and lazy evaluation,
Mikhail Glushenkov25422542009-03-01 18:09:47 +0000[diff] [blame]306lexical closures, a hygienic macro system (also based on term rewriting),
Chris Lattner53e06f92009-02-26 22:33:38 +0000[diff] [blame]307built-in list and matrix support (including list and matrix comprehensions) and
308an easy-to-use C interface. The interpreter uses LLVM as a backend to
309 JIT-compile Pure programs to fast native code.</p>
310
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]311<p>Pure versions ??? and later have been tested and are known to work with
312LLVM 2.7 (and continue to work with older LLVM releases >= 2.3 as well).
Chris Lattner53e06f92009-02-26 22:33:38 +0000[diff] [blame]313</p>
314</div>
315
316
317<!--=========================================================================-->
318<div class="doc_subsection">
319<a name="ldc">LLVM D Compiler</a>
320</div>
321
322<div class="doc_text">
323<p>
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]324<a href="http://www.dsource.org/projects/ldc">LDC</a> is an implementation of
325the D Programming Language using the LLVM optimizer and code generator.
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]326The LDC project works great with the LLVM 2.6 release. General improvements in
John Criswellea03c9d2009-03-02 15:28:15 +0000[diff] [blame]327this
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]328cycle have included new inline asm constraint handling, better debug info
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]329support, general bug fixes and better x86-64 support. This has allowed
330some major improvements in LDC, getting it much closer to being as
Chris Lattner53e06f92009-02-26 22:33:38 +0000[diff] [blame]331fully featured as the original DMD compiler from DigitalMars.
332</p>
333</div>
334
Chris Lattnerfb23a962009-02-28 18:58:01 +0000[diff] [blame]335<!--=========================================================================-->
336<div class="doc_subsection">
337<a name="RoadsendPHP">Roadsend PHP</a>
338</div>
339
340<div class="doc_text">
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]341<p>
342<a href="http://code.roadsend.com/rphp">Roadsend PHP</a> (rphp) is an open
Chris Lattner0c72d8f2009-03-02 19:07:24 +0000[diff] [blame]343source implementation of the PHP programming
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]344language that uses LLVM for its optimizer, JIT and static compiler. This is a
Chris Lattner0c72d8f2009-03-02 19:07:24 +0000[diff] [blame]345reimplementation of an earlier project that is now based on LLVM.</p>
Chris Lattnerfb23a962009-02-28 18:58:01 +0000[diff] [blame]346</div>
Chris Lattner53e06f92009-02-26 22:33:38 +0000[diff] [blame]347
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]348<!--=========================================================================-->
349<div class="doc_subsection">
350<a name="UnladenSwallow">Unladen Swallow</a>
351</div>
352
353<div class="doc_text">
354<p>
355<a href="http://code.google.com/p/unladen-swallow/">Unladen Swallow</a> is a
356branch of <a href="http://python.org/">Python</a> intended to be fully
357compatible and significantly faster. It uses LLVM's optimization passes and JIT
358compiler.</p>
359</div>
360
361<!--=========================================================================-->
362<div class="doc_subsection">
363<a name="llvm-lua">llvm-lua</a>
364</div>
365
366<div class="doc_text">
367<p>
368<a href="http://code.google.com/p/llvm-lua/">LLVM-Lua</a> uses LLVM to add JIT
369and static compiling support to the Lua VM. Lua bytecode is analyzed to
370remove type checks, then LLVM is used to compile the bytecode down to machine
371code.</p>
372</div>
373
374<!--=========================================================================-->
375<div class="doc_subsection">
376<a name="icedtea">IcedTea Java Virtual Machine Implementation</a>
377</div>
378
379<div class="doc_text">
380<p>
381<a href="http://icedtea.classpath.org/wiki/Main_Page">IcedTea</a> provides a
382harness to build OpenJDK using only free software build tools and to provide
383replacements for the not-yet free parts of OpenJDK. One of the extensions that
384IcedTea provides is a new JIT compiler named <a
385href="http://icedtea.classpath.org/wiki/ZeroSharkFaq">Shark</a> which uses LLVM
386to provide native code generation without introducing processor-dependent
387code.
388</p>
389</div>
390
391
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]392
393<!-- *********************************************************************** -->
394<div class="doc_section">
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]395 <a name="whatsnew">What's New in LLVM 2.7?</a>
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]396</div>
397<!-- *********************************************************************** -->
398
Chris Lattnerb7bc2aa2008-06-08 22:59:35 +0000[diff] [blame]399<div class="doc_text">
400
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]401<p>This release includes a huge number of bug fixes, performance tweaks and
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]402minor improvements. Some of the major improvements and new features are listed
403in this section.
Chris Lattnerb7bc2aa2008-06-08 22:59:35 +0000[diff] [blame]404</p>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]405
Chris Lattnerb7bc2aa2008-06-08 22:59:35 +0000[diff] [blame]406</div>
407
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]408<!--=========================================================================-->
Chris Lattner625a3d82008-06-08 21:34:41 +0000[diff] [blame]409<div class="doc_subsection">
Chris Lattnercdc44ed2008-02-06 18:00:06 +0000[diff] [blame]410<a name="majorfeatures">Major New Features</a>
411</div>
412
413<div class="doc_text">
414
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]415<p>LLVM 2.7 includes several major new capabilities:</p>
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]416
417<ul>
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]418<li>...</li>
Chris Lattner458e79f2008-02-10 08:18:42 +0000[diff] [blame]419</ul>
420
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]421</div>
422
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]423<!--=========================================================================-->
424<div class="doc_subsection">
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]425<a name="coreimprovements">LLVM IR and Core Improvements</a>
Chris Lattnerdd6acc02008-02-10 08:17:19 +0000[diff] [blame]426</div>
427
428<div class="doc_text">
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]429<p>LLVM IR has several new features for better support of new targets and that
430expose new optimization opportunities:</p>
Chris Lattnerdd6acc02008-02-10 08:17:19 +0000[diff] [blame]431
Chris Lattnerb7112222008-06-05 06:25:56 +0000[diff] [blame]432<ul>
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]433<li>...</li>
Chris Lattnerdd6acc02008-02-10 08:17:19 +0000[diff] [blame]434</ul>
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]435
Chris Lattnerdd6acc02008-02-10 08:17:19 +0000[diff] [blame]436</div>
437
438<!--=========================================================================-->
439<div class="doc_subsection">
Chris Lattner2b8a52e2008-02-10 07:46:44 +0000[diff] [blame]440<a name="optimizer">Optimizer Improvements</a>
441</div>
442
443<div class="doc_text">
444
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]445<p>In addition to a large array of minor performance tweaks and bug fixes, this
Chris Lattner25879d72008-10-13 21:50:36 +0000[diff] [blame]446release includes a few major enhancements and additions to the optimizers:</p>
Chris Lattner2b8a52e2008-02-10 07:46:44 +0000[diff] [blame]447
448<ul>
449
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]450<li>...</li>
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]451
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]452</ul>
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]453
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]454</div>
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]455
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]456
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]457<!--=========================================================================-->
458<div class="doc_subsection">
459<a name="executionengine">Interpreter and JIT Improvements</a>
460</div>
Chris Lattner25879d72008-10-13 21:50:36 +0000[diff] [blame]461
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]462<div class="doc_text">
463
464<ul>
Jeffrey Yasskin9fb8ce82010-01-29 19:10:38 +0000[diff] [blame]465<li>The JIT now <a
466href="http://llvm.org/viewvc/llvm-project?view=rev&revision=85295">defaults
467to compiling eagerly</a> to avoid a race condition in the lazy JIT.
468Clients that still want the lazy JIT can switch it on by calling
469<tt>ExecutionEngine::DisableLazyCompilation(false)</tt>.</li>
Jeffrey Yasskine0913882010-02-11 01:07:39 +0000[diff] [blame]470<li>It is now possible to create more than one JIT instance in the same process.
471These JITs can generate machine code in parallel,
472although <a href="http://llvm.org/docs/ProgrammersManual.html#jitthreading">you
473still have to obey the other threading restrictions</a>.</li>
Chris Lattner7795ea92008-06-08 02:45:07 +0000[diff] [blame]474</ul>
475
476</div>
477
478<!--=========================================================================-->
479<div class="doc_subsection">
Chris Lattnerd434bfb2009-03-02 03:24:11 +0000[diff] [blame]480<a name="codegen">Target Independent Code Generator Improvements</a>
Chris Lattner7795ea92008-06-08 02:45:07 +0000[diff] [blame]481</div>
482
483<div class="doc_text">
484
Mikhail Glushenkov25422542009-03-01 18:09:47 +0000[diff] [blame]485<p>We have put a significant amount of work into the code generator
486infrastructure, which allows us to implement more aggressive algorithms and make
487it run faster:</p>
Chris Lattner7795ea92008-06-08 02:45:07 +0000[diff] [blame]488
489<ul>
Chris Lattnerd434bfb2009-03-02 03:24:11 +0000[diff] [blame]490
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]491<li>...</li>
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]492</ul>
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]493</div>
494
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]495<!--=========================================================================-->
496<div class="doc_subsection">
497<a name="x86">X86-32 and X86-64 Target Improvements</a>
498</div>
499
500<div class="doc_text">
501<p>New features of the X86 target include:
502</p>
503
504<ul>
Chris Lattnerd434bfb2009-03-02 03:24:11 +0000[diff] [blame]505
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]506<li>...</li>
Chris Lattnerd434bfb2009-03-02 03:24:11 +0000[diff] [blame]507
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]508</ul>
509
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]510</div>
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]511
512<!--=========================================================================-->
513<div class="doc_subsection">
Chris Lattner6b8bf782009-02-26 07:32:11 +0000[diff] [blame]514<a name="pic16">PIC16 Target Improvements</a>
515</div>
516
517<div class="doc_text">
518<p>New features of the PIC16 target include:
519</p>
520
521<ul>
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]522<li>...</li>
Chris Lattner6b8bf782009-02-26 07:32:11 +0000[diff] [blame]523</ul>
524
525<p>Things not yet supported:</p>
526
527<ul>
Chris Lattner6b8bf782009-02-26 07:32:11 +0000[diff] [blame]528<li>Variable arguments.</li>
Chris Lattnerd434bfb2009-03-02 03:24:11 +0000[diff] [blame]529<li>Interrupts/programs.</li>
Chris Lattner6b8bf782009-02-26 07:32:11 +0000[diff] [blame]530</ul>
531
532</div>
533
Chris Lattner6b8bf782009-02-26 07:32:11 +0000[diff] [blame]534<!--=========================================================================-->
535<div class="doc_subsection">
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]536<a name="ARM">ARM Target Improvements</a>
Chris Lattnerc92d7692009-03-01 02:30:21 +0000[diff] [blame]537</div>
538
539<div class="doc_text">
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]540<p>New features of the ARM target include:
541</p>
Chris Lattnerc92d7692009-03-01 02:30:21 +0000[diff] [blame]542
543<ul>
Chris Lattnerc92d7692009-03-01 02:30:21 +0000[diff] [blame]544
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]545<li>...</li>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]546</ul>
Chris Lattnerc92d7692009-03-01 02:30:21 +0000[diff] [blame]547
Chris Lattnerc92d7692009-03-01 02:30:21 +0000[diff] [blame]548
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]549</div>
Chris Lattnerc92d7692009-03-01 02:30:21 +0000[diff] [blame]550
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]551<!--=========================================================================-->
552<div class="doc_subsection">
553<a name="OtherTarget">Other Target Specific Improvements</a>
554</div>
Chris Lattnerc92d7692009-03-01 02:30:21 +0000[diff] [blame]555
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]556<div class="doc_text">
557<p>New features of other targets include:
558</p>
559
560<ul>
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]561<li>...</li>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]562</ul>
563
564</div>
565
566<!--=========================================================================-->
567<div class="doc_subsection">
568<a name="newapis">New Useful APIs</a>
569</div>
570
571<div class="doc_text">
572
573<p>This release includes a number of new APIs that are used internally, which
574 may also be useful for external clients.
575</p>
576
577<ul>
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]578<li>...</li>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]579</ul>
580
581
582</div>
583
584<!--=========================================================================-->
585<div class="doc_subsection">
586<a name="otherimprovements">Other Improvements and New Features</a>
587</div>
588
589<div class="doc_text">
590<p>Other miscellaneous features include:</p>
591
592<ul>
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]593<li>...</li>
Chris Lattnerc92d7692009-03-01 02:30:21 +0000[diff] [blame]594</ul>
595
596</div>
597
Chris Lattner6cb64032008-06-05 08:02:49 +0000[diff] [blame]598
599<!--=========================================================================-->
600<div class="doc_subsection">
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]601<a name="changes">Major Changes and Removed Features</a>
602</div>
603
604<div class="doc_text">
605
Chris Lattner934e2d42008-10-13 22:06:31 +0000[diff] [blame]606<p>If you're already an LLVM user or developer with out-of-tree changes based
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]607on LLVM 2.6, this section lists some "gotchas" that you may run into upgrading
Chris Lattner934e2d42008-10-13 22:06:31 +0000[diff] [blame]608from the previous release.</p>
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]609
610<ul>
Jeffrey Yasskin914050b2010-02-09 23:03:44 +0000[diff] [blame]611<li>The LLVM interpreter now defaults to <em>not</em> using <tt>libffi</tt> even
612if you have it installed. This makes it more likely that an LLVM built on one
613system will work when copied to a similar system. To use <tt>libffi</tt>,
614configure with <tt>--enable-libffi</tt>.
615</li>
Chris Lattner934e2d42008-10-13 22:06:31 +0000[diff] [blame]616</ul>
617
618
619<p>In addition, many APIs have changed in this release. Some of the major LLVM
620API changes are:</p>
621
622<ul>
Jeffrey Yasskin4a8b1da2010-01-28 01:41:20 +0000[diff] [blame]623<li><tt>ModuleProvider</tt> has been <a
624href="http://llvm.org/viewvc/llvm-project?view=rev&revision=94686">removed</a>
625and its methods moved to <tt>Module</tt> and <tt>GlobalValue</tt>.
626Most clients can remove uses of <tt>ExistingModuleProvider</tt>,
627replace <tt>getBitcodeModuleProvider</tt> with
628<tt>getLazyBitcodeModule</tt>, and pass their <tt>Module</tt> to
629functions that used to accept <tt>ModuleProvider</tt>. Clients who
630wrote their own <tt>ModuleProvider</tt>s will need to derive from
631<tt>GVMaterializer</tt> instead and use
632<tt>Module::setMaterializer</tt> to attach it to a
633<tt>Module</tt>.</li>
634
635<li><tt>GhostLinkage</tt> has given up the ghost.
636<tt>GlobalValue</tt>s that have not yet been read from their backing
637storage have the same linkage they will have after being read in.
638Clients must replace calls to
639<tt>GlobalValue::hasNotBeenReadFromBitcode</tt> with
640<tt>GlobalValue::isMaterializable</tt>.</li>
Daniel Dunbar1e96fca2010-02-10 04:09:52 +0000[diff] [blame]641
642<li>FIXME: Debug info has been totally redone. Add pointers to new APIs. Substantial caveats about compatibility of .ll and .bc files.</li>
643
Daniel Dunbar3e255da2010-02-14 01:47:19 +0000[diff] [blame]644<li>The <tt>llvm/Support/DataTypes.h</tt> header has moved
645to <tt>llvm/System/DataTypes.h</tt>.</li>
646
Duncan Sands80c430a2010-02-17 17:20:17 +0000[diff] [blame]647<li>The <tt>isInteger</tt>, <tt>isIntOrIntVector</tt>, <tt>isFloatingPoint</tt>,
648<tt>isFPOrFPVector</tt> and <tt>isFPOrFPVector</tt> methods have been renamed
649<tt>isIntegerTy</tt>, <tt>isIntOrIntVectorTy</tt>, <tt>isFloatingPointTy</tt>,
650<tt>isFPOrFPVectorTy</tt> and <tt>isFPOrFPVectorTy</tt> respectively.</li>
Devang Pateldbf83832008-10-14 20:03:43 +0000[diff] [blame]651</ul>
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]652
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]653</div>
654
655
656
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]657<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]658<div class="doc_section">
659 <a name="portability">Portability and Supported Platforms</a>
660</div>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]661<!-- *********************************************************************** -->
662
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]663<div class="doc_text">
664
John Criswell64307722004-12-08 20:35:47 +0000[diff] [blame]665<p>LLVM is known to work on the following platforms:</p>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]666
667<ul>
Mikhail Glushenkov25422542009-03-01 18:09:47 +0000[diff] [blame]668<li>Intel and AMD machines (IA32, X86-64, AMD64, EMT-64) running Red Hat
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]669 Linux, Fedora Core, FreeBSD and AuroraUX (and probably other unix-like
670 systems).</li>
Mikhail Glushenkov25422542009-03-01 18:09:47 +0000[diff] [blame]671<li>PowerPC and X86-based Mac OS X systems, running 10.3 and above in 32-bit
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]672 and 64-bit modes.</li>
Chris Lattnercdc44ed2008-02-06 18:00:06 +0000[diff] [blame]673<li>Intel and AMD machines running on Win32 using MinGW libraries (native).</li>
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]674<li>Intel and AMD machines running on Win32 with the Cygwin libraries (limited
675 support is available for native builds with Visual C++).</li>
Chris Lattner51948622009-10-16 16:30:58 +0000[diff] [blame]676<li>Sun x86 and AMD64 machines running Solaris 10, OpenSolaris 0906.</li>
John Criswelld5234922005-05-13 20:28:15 +0000[diff] [blame]677<li>Alpha-based machines running Debian GNU/Linux.</li>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]678</ul>
679
Chris Lattner618a99f2008-06-05 06:57:39 +0000[diff] [blame]680<p>The core LLVM infrastructure uses GNU autoconf to adapt itself
Brian Gaekee3e557e2004-05-09 05:28:35 +0000[diff] [blame]681to the machine and operating system on which it is built. However, minor
682porting may be required to get LLVM to work on new platforms. We welcome your
683portability patches and reports of successful builds or error messages.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]684
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]685</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]686
687<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]688<div class="doc_section">
689 <a name="knownproblems">Known Problems</a>
690</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]691<!-- *********************************************************************** -->
692
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]693<div class="doc_text">
694
Mikhail Glushenkov25422542009-03-01 18:09:47 +0000[diff] [blame]695<p>This section contains significant known problems with the LLVM system,
Chris Lattner2a092392008-11-10 05:40:34 +0000[diff] [blame]696listed by component. If you run into a problem, please check the <a
Chris Lattnera69595e2005-10-29 07:07:09 +0000[diff] [blame]697href="http://llvm.org/bugs/">LLVM bug database</a> and submit a bug if
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]698there isn't already one.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]699
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]700<ul>
701<li>The llvm-gcc bootstrap will fail with some versions of binutils (e.g. 2.15)
702 with a message of "<tt><a href="http://llvm.org/PR5004">Error: can not do 8
703 byte pc-relative relocation</a></tt>" when building C++ code. We intend to
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]704 fix this on mainline, but a workaround is to upgrade to binutils 2.17 or
705 later.</li>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]706
707<li>LLVM will not correctly compile on Solaris and/or OpenSolaris
708using the stock GCC 3.x.x series 'out the box',
Chris Lattner6e41c792009-11-03 21:50:09 +0000[diff] [blame]709See: <a href="GettingStarted.html#brokengcc">Broken versions of GCC and other tools</a>.
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]710However, A <a href="http://pkg.auroraux.org/GCC">Modern GCC Build</a>
711for x86/x86-64 has been made available from the third party AuroraUX Project
712that has been meticulously tested for bootstrapping LLVM &amp; Clang.</li>
713</ul>
714
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]715</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]716
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]717<!-- ======================================================================= -->
718<div class="doc_subsection">
719 <a name="experimental">Experimental features included with this release</a>
720</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]721
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]722<div class="doc_text">
723
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]724<p>The following components of this LLVM release are either untested, known to
725be broken or unreliable, or are in early development. These components should
726not be relied on, and bugs should not be filed against them, but they may be
727useful to some people. In particular, if you would like to work on one of these
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]728components, please contact us on the <a
729href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev list</a>.</p>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]730
731<ul>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]732<li>The MSIL, Alpha, SPU, MIPS, PIC16, Blackfin, MSP430 and SystemZ backends are
733 experimental.</li>
Bill Wendling89cd82f2009-03-02 07:54:14 +0000[diff] [blame]734<li>The <tt>llc</tt> "<tt>-filetype=asm</tt>" (the default) is the only
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]735 supported value for this option. The ELF writer is experimental.</li>
736<li>The implementation of Andersen's Alias Analysis has many known bugs.</li>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]737</ul>
738
739</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]740
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]741<!-- ======================================================================= -->
742<div class="doc_subsection">
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]743 <a name="x86-be">Known problems with the X86 back-end</a>
John Criswell3bdbd302005-11-08 21:11:33 +0000[diff] [blame]744</div>
745
746<div class="doc_text">
747
748<ul>
Anton Korobeynikov486c7d32008-06-08 10:24:13 +0000[diff] [blame]749 <li>The X86 backend does not yet support
750 all <a href="http://llvm.org/PR879">inline assembly that uses the X86
751 floating point stack</a>. It supports the 'f' and 't' constraints, but not
752 'u'.</li>
Chris Lattnerb076b002008-06-08 21:19:07 +0000[diff] [blame]753 <li>The X86 backend generates inefficient floating point code when configured
754 to generate code for systems that don't have SSE2.</li>
Duncan Sands0bc15262008-06-08 19:38:43 +0000[diff] [blame]755 <li>Win64 code generation wasn't widely tested. Everything should work, but we
John Criswellea03c9d2009-03-02 15:28:15 +0000[diff] [blame]756 expect small issues to happen. Also, llvm-gcc cannot build the mingw64
757 runtime currently due
Anton Korobeynikov486c7d32008-06-08 10:24:13 +0000[diff] [blame]758 to <a href="http://llvm.org/PR2255">several</a>
John Criswellea03c9d2009-03-02 15:28:15 +0000[diff] [blame]759 <a href="http://llvm.org/PR2257">bugs</a> and due to lack of support for
760 the
761 'u' inline assembly constraint and for X87 floating point inline assembly.</li>
Dan Gohman721b3722008-06-08 23:05:11 +0000[diff] [blame]762 <li>The X86-64 backend does not yet support the LLVM IR instruction
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]763 <tt>va_arg</tt>. Currently, the llvm-gcc and front-ends support variadic
Dan Gohman721b3722008-06-08 23:05:11 +0000[diff] [blame]764 argument constructs on X86-64 by lowering them manually.</li>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]765</ul>
766
767</div>
768
769<!-- ======================================================================= -->
770<div class="doc_subsection">
771 <a name="ppc-be">Known problems with the PowerPC back-end</a>
772</div>
773
774<div class="doc_text">
775
776<ul>
Nicolas Geoffray77d99502007-05-15 09:21:28 +0000[diff] [blame]777<li>The Linux PPC32/ABI support needs testing for the interpreter and static
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]778compilation, and lacks support for debug information.</li>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]779</ul>
780
781</div>
782
783<!-- ======================================================================= -->
784<div class="doc_subsection">
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]785 <a name="arm-be">Known problems with the ARM back-end</a>
786</div>
787
788<div class="doc_text">
789
790<ul>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]791<li>Support for the Advanced SIMD (Neon) instruction set is still incomplete
792and not well tested. Some features may not work at all, and the code quality
793may be poor in some cases.</li>
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]794<li>Thumb mode works only on ARMv6 or higher processors. On sub-ARMv6
Duncan Sands47fc0a22007-09-26 15:59:54 +0000[diff] [blame]795processors, thumb programs can crash or produce wrong
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]796results (<a href="http://llvm.org/PR1388">PR1388</a>).</li>
John Criswellea03c9d2009-03-02 15:28:15 +0000[diff] [blame]797<li>Compilation for ARM Linux OABI (old ABI) is supported but not fully tested.
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]798</li>
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]799</ul>
800
801</div>
802
803<!-- ======================================================================= -->
804<div class="doc_subsection">
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]805 <a name="sparc-be">Known problems with the SPARC back-end</a>
806</div>
807
808<div class="doc_text">
809
810<ul>
John Criswellea03c9d2009-03-02 15:28:15 +0000[diff] [blame]811<li>The SPARC backend only supports the 32-bit SPARC ABI (-m32); it does not
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]812 support the 64-bit SPARC ABI (-m64).</li>
813</ul>
814
815</div>
816
817<!-- ======================================================================= -->
818<div class="doc_subsection">
Bruno Cardoso Lopes24eb3de2008-10-25 14:56:26 +0000[diff] [blame]819 <a name="mips-be">Known problems with the MIPS back-end</a>
820</div>
821
822<div class="doc_text">
823
824<ul>
Bruno Cardoso Lopes24eb3de2008-10-25 14:56:26 +0000[diff] [blame]825<li>64-bit MIPS targets are not supported yet.</li>
826</ul>
827
828</div>
829
830<!-- ======================================================================= -->
831<div class="doc_subsection">
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]832 <a name="alpha-be">Known problems with the Alpha back-end</a>
833</div>
834
835<div class="doc_text">
836
837<ul>
838
839<li>On 21164s, some rare FP arithmetic sequences which may trap do not have the
840appropriate nops inserted to ensure restartability.</li>
841
John Criswell3bdbd302005-11-08 21:11:33 +0000[diff] [blame]842</ul>
843</div>
844
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]845<!-- ======================================================================= -->
846<div class="doc_subsection">
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]847 <a name="c-be">Known problems with the C back-end</a>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]848</div>
849
850<div class="doc_text">
851
852<ul>
Chris Lattnera1a4c9a2008-06-05 06:35:40 +0000[diff] [blame]853<li><a href="http://llvm.org/PR802">The C backend has only basic support for
854 inline assembly code</a>.</li>
Chris Lattner8e061162007-09-26 06:01:35 +0000[diff] [blame]855<li><a href="http://llvm.org/PR1658">The C backend violates the ABI of common
856 C++ programs</a>, preventing intermixing between C++ compiled by the CBE and
Gabor Greif75b2f762009-03-02 12:02:51 +0000[diff] [blame]857 C++ code compiled with <tt>llc</tt> or native compilers.</li>
Duncan Sandse09506a2008-02-10 13:40:55 +0000[diff] [blame]858<li>The C backend does not support all exception handling constructs.</li>
Duncan Sands3aa36732009-02-25 11:51:54 +0000[diff] [blame]859<li>The C backend does not support arbitrary precision integers.</li>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]860</ul>
861
862</div>
John Criswell3bdbd302005-11-08 21:11:33 +0000[diff] [blame]863
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]864
865<!-- ======================================================================= -->
866<div class="doc_subsection">
Chris Lattnera1a4c9a2008-06-05 06:35:40 +0000[diff] [blame]867 <a name="c-fe">Known problems with the llvm-gcc C front-end</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]868</div>
Chris Lattner178f3db2003-10-02 05:07:23 +0000[diff] [blame]869
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]870<div class="doc_text">
Chris Lattner72a269f2006-03-03 00:34:26 +0000[diff] [blame]871
Chris Lattnera1a4c9a2008-06-05 06:35:40 +0000[diff] [blame]872<p>The only major language feature of GCC not supported by llvm-gcc is
873 the <tt>__builtin_apply</tt> family of builtins. However, some extensions
874 are only supported on some targets. For example, trampolines are only
Duncan Sands56448462008-06-08 20:18:35 +0000[diff] [blame]875 supported on some targets (these are used when you take the address of a
876 nested function).</p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]877
Chris Lattnera1a4c9a2008-06-05 06:35:40 +0000[diff] [blame]878<p>If you run into GCC extensions which are not supported, please let us know.
879</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]880
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]881</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]882
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]883<!-- ======================================================================= -->
884<div class="doc_subsection">
Chris Lattnera1a4c9a2008-06-05 06:35:40 +0000[diff] [blame]885 <a name="c++-fe">Known problems with the llvm-gcc C++ front-end</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]886</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]887
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]888<div class="doc_text">
889
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]890<p>The C++ front-end is considered to be fully
Chris Lattnerb5bb5972004-12-07 08:04:13 +0000[diff] [blame]891tested and works for a number of non-trivial programs, including LLVM
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]892itself, Qt, Mozilla, etc.</p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]893
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]894<ul>
Anton Korobeynikov28f08aa2008-10-11 18:27:16 +0000[diff] [blame]895<li>Exception handling works well on the X86 and PowerPC targets. Currently
Chris Lattner2a092392008-11-10 05:40:34 +0000[diff] [blame]896 only Linux and Darwin targets are supported (both 32 and 64 bit).</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]897</ul>
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]898
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]899</div>
900
Chris Lattner7292fb12008-10-30 03:58:13 +0000[diff] [blame]901<!-- ======================================================================= -->
902<div class="doc_subsection">
903 <a name="fortran-fe">Known problems with the llvm-gcc Fortran front-end</a>
904</div>
905
906<div class="doc_text">
Gabor Greife5f9d672008-11-04 21:50:59 +0000[diff] [blame]907<ul>
Chris Lattner7292fb12008-10-30 03:58:13 +0000[diff] [blame]908<li>Fortran support generally works, but there are still several unresolved bugs
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]909 in <a href="http://llvm.org/bugs/">Bugzilla</a>. Please see the
910 tools/gfortran component for details.</li>
Gabor Greife5f9d672008-11-04 21:50:59 +0000[diff] [blame]911</ul>
Chris Lattner7292fb12008-10-30 03:58:13 +0000[diff] [blame]912</div>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]913
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]914<!-- ======================================================================= -->
915<div class="doc_subsection">
Chris Lattnera1a4c9a2008-06-05 06:35:40 +0000[diff] [blame]916 <a name="ada-fe">Known problems with the llvm-gcc Ada front-end</a>
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]917</div>
918
919<div class="doc_text">
John Criswellea03c9d2009-03-02 15:28:15 +0000[diff] [blame]920The llvm-gcc 4.2 Ada compiler works fairly well; however, this is not a mature
921technology, and problems should be expected.
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]922<ul>
Duncan Sands56448462008-06-08 20:18:35 +0000[diff] [blame]923<li>The Ada front-end currently only builds on X86-32. This is mainly due
John Criswellea03c9d2009-03-02 15:28:15 +0000[diff] [blame]924to lack of trampoline support (pointers to nested functions) on other platforms.
925However, it <a href="http://llvm.org/PR2006">also fails to build on X86-64</a>
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]926which does support trampolines.</li>
927<li>The Ada front-end <a href="http://llvm.org/PR2007">fails to bootstrap</a>.
Duncan Sandsd34bf762009-02-25 11:59:06 +0000[diff] [blame]928This is due to lack of LLVM support for <tt>setjmp</tt>/<tt>longjmp</tt> style
929exception handling, which is used internally by the compiler.
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]930Workaround: configure with <tt>--disable-bootstrap</tt>.</li>
Duncan Sandsaef747f2008-10-13 17:27:23 +0000[diff] [blame]931<li>The c380004, <a href="http://llvm.org/PR2010">c393010</a>
932and <a href="http://llvm.org/PR2421">cxg2021</a> ACATS tests fail
Duncan Sandsd34bf762009-02-25 11:59:06 +0000[diff] [blame]933(c380004 also fails with gcc-4.2 mainline).
934If the compiler is built with checks disabled then <a href="http://llvm.org/PR2010">c393010</a>
935causes the compiler to go into an infinite loop, using up all system memory.</li>
Duncan Sands2dbb00e2009-03-02 16:35:57 +0000[diff] [blame]936<li>Some GCC specific Ada tests continue to crash the compiler.</li>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]937<li>The <tt>-E</tt> binder option (exception backtraces)
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]938<a href="http://llvm.org/PR1982">does not work</a> and will result in programs
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]939crashing if an exception is raised. Workaround: do not use <tt>-E</tt>.</li>
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]940<li>Only discrete types <a href="http://llvm.org/PR1981">are allowed to start
941or finish at a non-byte offset</a> in a record. Workaround: do not pack records
942or use representation clauses that result in a field of a non-discrete type
943starting or finishing in the middle of a byte.</li>
Chris Lattnerb076b002008-06-08 21:19:07 +0000[diff] [blame]944<li>The <tt>lli</tt> interpreter <a href="http://llvm.org/PR2009">considers
945'main' as generated by the Ada binder to be invalid</a>.
946Workaround: hand edit the file to use pointers for <tt>argv</tt> and
947<tt>envp</tt> rather than integers.</li>
948<li>The <tt>-fstack-check</tt> option <a href="http://llvm.org/PR2008">is
949ignored</a>.</li>
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]950</ul>
951</div>
952
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]953<!-- ======================================================================= -->
954<div class="doc_subsection">
955 <a name="ocaml-bindings">Known problems with the O'Caml bindings</a>
956</div>
957
958<div class="doc_text">
959
960<p>The <tt>Llvm.Linkage</tt> module is broken, and has incorrect values. Only
961<tt>Llvm.Linkage.External</tt>, <tt>Llvm.Linkage.Available_externally</tt>, and
962<tt>Llvm.Linkage.Link_once</tt> will be correct. If you need any of the other linkage
963modes, you'll have to write an external C library in order to expose the
964functionality. This has been fixed in the trunk.</p>
965</div>
966
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]967<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]968<div class="doc_section">
969 <a name="additionalinfo">Additional Information</a>
970</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]971<!-- *********************************************************************** -->
972
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]973<div class="doc_text">
974
Chris Lattnercb5596d2005-05-16 17:13:10 +0000[diff] [blame]975<p>A wide variety of additional information is available on the <a
Chris Lattnere0c1df42007-05-18 00:44:29 +0000[diff] [blame]976href="http://llvm.org">LLVM web page</a>, in particular in the <a
977href="http://llvm.org/docs/">documentation</a> section. The web page also
Reid Spencerc7f87f22007-07-09 08:04:31 +0000[diff] [blame]978contains versions of the API documentation which is up-to-date with the
979Subversion version of the source code.
Misha Brukman96158092005-03-30 19:14:24 +0000[diff] [blame]980You can access versions of these documents specific to this release by going
981into the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]982
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]983<p>If you have any questions or comments about LLVM, please feel free to contact
Chris Lattnera69595e2005-10-29 07:07:09 +0000[diff] [blame]984us via the <a href="http://llvm.org/docs/#maillist"> mailing
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]985lists</a>.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]986
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]987</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]988
989<!-- *********************************************************************** -->
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]990
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]991<hr>
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]992<address>
Misha Brukman8834af92003-12-21 22:53:21 +0000[diff] [blame]993 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman86242e12008-12-11 17:34:48 +0000[diff] [blame]994 src="http://jigsaw.w3.org/css-validator/images/vcss-blue" alt="Valid CSS"></a>
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]995 <a href="http://validator.w3.org/check/referer"><img
Misha Brukman86242e12008-12-11 17:34:48 +0000[diff] [blame]996 src="http://www.w3.org/Icons/valid-html401-blue" alt="Valid HTML 4.01"></a>
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]997
Chris Lattnere0c1df42007-05-18 00:44:29 +0000[diff] [blame]998 <a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]999 Last modified: $Date$
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]1000</address>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]1001
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]1002</body>
1003</html>