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gerrit-public.fairphone.software / fp2-dev / platform / external / llvm / 450a31edde46234dff2a681006878a853efc1027 / . / docs / ReleaseNotes.html
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Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
2 "http://www.w3.org/TR/html4/strict.dtd">
3<html>
4<head>
Reid Spencer6454ed32004-11-18 18:38:58 +0000[diff] [blame]5 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]6 <link rel="stylesheet" href="llvm.css" type="text/css">
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]7 <title>LLVM 2.7 Release Notes</title>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]8</head>
9<body>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]10
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]11<div class="doc_title">LLVM 2.7 Release Notes</div>
Mikhail Glushenkovea65d7d2008-10-13 02:08:34 +0000[diff] [blame]12
Chris Lattner0e464a92010-03-17 04:02:39 +0000[diff] [blame]13<img align=right src="http://llvm.org/img/DragonSmall.png"
14 width="136" height="136">
15
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]16<ol>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]17 <li><a href="#intro">Introduction</a></li>
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]18 <li><a href="#subproj">Sub-project Status Update</a></li>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]19 <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 +0000[diff] [blame]21 <li><a href="GettingStarted.html">Installation Instructions</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]22 <li><a href="#portability">Portability and Supported Platforms</a></li>
Dan Gohman44aa9212008-10-14 16:23:02 +0000[diff] [blame]23 <li><a href="#knownproblems">Known Problems</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]24 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]25</ol>
26
Chris Lattner7911ce22004-05-23 21:07:27 +0000[diff] [blame]27<div class="doc_author">
Dan Gohman44aa9212008-10-14 16:23:02 +0000[diff] [blame]28 <p>Written by the <a href="http://llvm.org">LLVM Team</a></p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]29</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]30
Chris Lattner00736fc2010-04-13 06:37:00 +0000[diff] [blame]31<!--
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]32<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 +0000[diff] [blame]36Release Notes</a>.</h1>-->
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]37
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]38<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]39<div class="doc_section">
40 <a name="intro">Introduction</a>
41</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]42<!-- *********************************************************************** -->
43
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]44<div class="doc_text">
45
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]46<p>This document contains the release notes for the LLVM Compiler
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]47Infrastructure, release 2.7. Here we describe the status of LLVM, including
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]48major improvements from the previous release and significant known problems.
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000[diff] [blame]49All LLVM releases may be downloaded from the <a
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]50href="http://llvm.org/releases/">LLVM releases web site</a>.</p>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]51
Chris Lattner7506b1d2004-12-07 08:04:13 +0000[diff] [blame]52<p>For more information about LLVM, including information about the latest
Chris Lattnerc463b272005-10-29 07:07:09 +0000[diff] [blame]53release, please check out the <a href="http://llvm.org/">main LLVM
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]54web site</a>. If you have questions or comments, the <a
Chris Lattnerc66bfef2010-03-17 04:41:49 +0000[diff] [blame]55href="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 +0000[diff] [blame]57
Mikhail Glushenkovea65d7d2008-10-13 02:08:34 +0000[diff] [blame]58<p>Note that if you are reading this file from a Subversion checkout or the
Chris Lattner84977642007-09-21 03:54:09 +0000[diff] [blame]59main LLVM web page, this document applies to the <i>next</i> release, not the
Gabor Greiffa933f82008-10-14 11:00:32 +0000[diff] [blame]60current one. To see the release notes for a specific release, please see the
Chris Lattner84977642007-09-21 03:54:09 +0000[diff] [blame]61<a href="http://llvm.org/releases/">releases page</a>.</p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]62
63</div>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]64
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]65
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]66<!--
67Almost dead code.
68 include/llvm/Analysis/LiveValues.h => Dan
69 lib/Transforms/IPO/MergeFunctions.cpp => consider for 2.8.
70 llvm/Analysis/PointerTracking.h => Edwin wants this, consider for 2.8.
Chris Lattner00736fc2010-04-13 06:37:00 +0000[diff] [blame]71 ABCD, GEPSplitterPass
Chris Lattner048fe3c2010-01-16 21:25:13 +0000[diff] [blame]72 MSIL backend?
Chris Lattnerdc910082010-03-17 06:41:58 +0000[diff] [blame]73 lib/Transforms/Utils/SSI.cpp -> ABCD depends on it.
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]74-->
75
76
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]77<!-- Features that need text if they're finished for 2.7:
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]78 strong phi elim
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]79 llvm.dbg.value: variable debug info for optimized code
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]80 loop dependence analysis
Chris Lattneracce85d2008-02-10 07:46:44 +0000[diff] [blame]81 -->
Mikhail Glushenkovea65d7d2008-10-13 02:08:34 +0000[diff] [blame]82
Chris Lattner547a3912008-10-12 19:47:48 +0000[diff] [blame]83 <!-- for announcement email:
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]84 Logo web page.
85 llvm devmtg
86 compiler_rt
87 KLEE web page at klee.llvm.org
88 Many new papers added to /pubs/
Chris Lattnerdc910082010-03-17 06:41:58 +0000[diff] [blame]89 Mention gcc plugin.
Chris Lattner74c80df2009-02-25 06:34:50 +0000[diff] [blame]90 -->
Chris Lattneracce85d2008-02-10 07:46:44 +0000[diff] [blame]91
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]92<!-- *********************************************************************** -->
93<div class="doc_section">
94 <a name="subproj">Sub-project Status Update</a>
Chris Lattnerea34f642008-06-08 21:34:41 +0000[diff] [blame]95</div>
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]96<!-- *********************************************************************** -->
Chris Lattnerea34f642008-06-08 21:34:41 +0000[diff] [blame]97
98<div class="doc_text">
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]99<p>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]100The LLVM 2.7 distribution currently consists of code from the core LLVM
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]101repository (which roughly includes the LLVM optimizers, code generators
102and supporting tools), the Clang repository and the llvm-gcc repository. In
103addition to this code, the LLVM Project includes other sub-projects that are in
104development. Here we include updates on these subprojects.
Bill Wendling63d8c552009-03-02 04:28:57 +0000[diff] [blame]105</p>
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]106
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]107</div>
108
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]109
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]110<!--=========================================================================-->
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]111<div class="doc_subsection">
Chris Lattnerfb97b2d2008-10-13 18:11:54 +0000[diff] [blame]112<a name="clang">Clang: C/C++/Objective-C Frontend Toolkit</a>
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]113</div>
114
115<div class="doc_text">
116
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]117<p>The <a href="http://clang.llvm.org/">Clang project</a> is ...</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]118
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]119<p>In the LLVM 2.7 time-frame, the Clang team has made many improvements:</p>
Bill Wendling741748a2008-10-27 09:27:33 +0000[diff] [blame]120
Daniel Dunbar13739432008-10-14 23:25:09 +0000[diff] [blame]121<ul>
Daniel Dunbar60dadb62010-03-25 16:09:18 +0000[diff] [blame]122<li>FIXME: C++! Include a link to cxx_compatibility.html</li>
123
124<li>FIXME: Static Analyzer improvements?</li>
125
126<li>CIndex API and Python bindings: Clang now includes a C API as part of the
127CIndex library. Although we make make some changes to the API in the future, it
128is intended to be stable and has been designed for use by external projects. See
129the Clang
130doxygen <a href="http://clang.llvm.org/doxygen/group__CINDEX.html">CIndex</a>
131documentation for more details. The CIndex API also includings an preliminary
132set of Python bindings.</li>
133
134<li>ARM Support: Clang now has ABI support for both the Darwin and Linux ARM
135ABIs. Coupled with many improvements to the LLVM ARM backend, Clang is now
136suitable for use as a a beta quality ARM compiler.</li>
Bill Wendling6bc15282009-03-02 04:28:18 +0000[diff] [blame]137</ul>
Chris Lattnerfb97b2d2008-10-13 18:11:54 +0000[diff] [blame]138</div>
139
140<!--=========================================================================-->
141<div class="doc_subsection">
142<a name="clangsa">Clang Static Analyzer</a>
143</div>
144
145<div class="doc_text">
146
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]147<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 +0000[diff] [blame]148includes an early stage static source code analysis tool for <a
149href="http://clang.llvm.org/StaticAnalysis.html">automatically finding bugs</a>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]150in C and Objective-C programs. The tool performs checks to find
Ted Kremenek8b3894c2009-02-27 07:01:32 +0000[diff] [blame]151bugs that occur on a specific path within a program.</p>
Chris Lattnercc042612008-10-14 00:52:49 +0000[diff] [blame]152
Chris Lattner0e464a92010-03-17 04:02:39 +0000[diff] [blame]153<p>In the LLVM 2.7 time-frame, the analyzer core has sprouted legs and...</p>
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]154
155</div>
156
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]157<!--=========================================================================-->
158<div class="doc_subsection">
Nicolas Geoffray99a4d302008-10-14 19:23:04 +0000[diff] [blame]159<a name="vmkit">VMKit: JVM/CLI Virtual Machine Implementation</a>
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]160</div>
161
162<div class="doc_text">
163<p>
Nicolas Geoffray99a4d302008-10-14 19:23:04 +0000[diff] [blame]164The <a href="http://vmkit.llvm.org/">VMKit project</a> is an implementation of
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]165a JVM and a CLI Virtual Machine (Microsoft .NET is an
166implementation of the CLI) using LLVM for static and just-in-time
167compilation.</p>
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]168
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]169<p>
Chris Lattnerbf8e5162010-03-29 18:34:13 +0000[diff] [blame]170With the release of LLVM 2.7, VMKit has shifted to a great framework for writing
171virtual machines. VMKit now offers precise and efficient garbage collection with
172multi-threading support, thanks to the MMTk memory management toolkit, as well
173as just in time and ahead of time compilation with LLVM. The major changes in
174VMKit 0.27 are:</p>
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]175
Nicolas Geoffray99a4d302008-10-14 19:23:04 +0000[diff] [blame]176<ul>
177
Chris Lattnerbf8e5162010-03-29 18:34:13 +0000[diff] [blame]178<li>Garbage collection: VMKit now uses the MMTk toolkit for garbage collectors.
179 The first collector to be ported is the MarkSweep collector, which is precise,
180 and drastically improves the performance of VMKit.</li>
181<li>Line number information in the JVM: by using the debug metadata of LLVM, the
182 JVM now supports precise line number information, useful when printing a stack
183 trace.</li>
184<li>Interface calls in the JVM: we implemented a variant of the Interface Method
185 Table technique for interface calls in the JVM.
186</li>
Nicolas Geoffray99a4d302008-10-14 19:23:04 +0000[diff] [blame]187
188</ul>
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]189</div>
190
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]191
192<!--=========================================================================-->
193<div class="doc_subsection">
194<a name="compiler-rt">compiler-rt: Compiler Runtime Library</a>
195</div>
196
197<div class="doc_text">
198<p>
199The new LLVM <a href="http://compiler-rt.llvm.org/">compiler-rt project</a>
200is a simple library that provides an implementation of the low-level
201target-specific hooks required by code generation and other runtime components.
202For example, when compiling for a 32-bit target, converting a double to a 64-bit
203unsigned integer is compiled into a runtime call to the "__fixunsdfdi"
204function. The compiler-rt library provides highly optimized implementations of
205this and other low-level routines (some are 3x faster than the equivalent
206libgcc routines).</p>
207
208<p>
209All of the code in the compiler-rt project is available under the standard LLVM
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]210License, a "BSD-style" license. New in LLVM 2.7: compiler_rt now
211supports ARM targets.</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]212
213</div>
214
215<!--=========================================================================-->
216<div class="doc_subsection">
Duncan Sands749fd832010-04-02 09:23:15 +0000[diff] [blame]217<a name="dragonegg">DragonEgg: llvm-gcc ported to gcc-4.5</a>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]218</div>
219
220<div class="doc_text">
221<p>
Duncan Sands749fd832010-04-02 09:23:15 +0000[diff] [blame]222<a href="http://dragonegg.llvm.org/">DragonEgg</a> is a port of llvm-gcc to
223gcc-4.5. Unlike llvm-gcc, which makes many intrusive changes to the underlying
224gcc-4.2 code, dragonegg in theory does not require any gcc-4.5 modifications
225whatsoever (currently one small patch is needed). This is thanks to the new
226<a href="http://gcc.gnu.org/wiki/plugins">gcc plugin architecture</a>, which
227makes it possible to modify the behaviour of gcc at runtime by loading a plugin,
228which is nothing more than a dynamic library which conforms to the gcc plugin
229interface. DragonEgg is a gcc plugin that causes the LLVM optimizers to be run
230instead of the gcc optimizers, and the LLVM code generators instead of the gcc
231code generators, just like llvm-gcc. To use it, you add
232"-fplugin=path/dragonegg.so" to the gcc-4.5 command line, and gcc-4.5 magically
233becomes llvm-gcc-4.5!
234</p>
235
236<p>
237DragonEgg is still a work in progress. Currently C works very well, while C++,
238Ada and Fortran work fairly well. All other languages either don't work at all,
239or only work poorly. For the moment only the x86-32 and x86-64 targets are
Duncan Sands51a51742010-04-20 19:40:58 +0000[diff] [blame]240supported, and only on linux and darwin (darwin needs an additional gcc patch).
Duncan Sands749fd832010-04-02 09:23:15 +0000[diff] [blame]241</p>
242
243<p>
Duncan Sands51a51742010-04-20 19:40:58 +0000[diff] [blame]244The first dragonegg release will occur shortly after llvm-2.7 is released.
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]245</p>
246
247</div>
248
249
250<!--=========================================================================-->
251<div class="doc_subsection">
252<a name="mc">llvm-mc: Machine Code Toolkit</a>
253</div>
254
255<div class="doc_text">
256<p>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]257The LLVM Machine Code (MC) Toolkit project is ...
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]258</p>
259
Chris Lattner450a31e2010-04-21 06:23:40 +0000[diff] [blame^]260<p>
261MC Disassembler (with blog post), MCInstPrinter. Many X86 backend and AsmPrinter simplifications
262Can transcode from GAS to intel syntax with "llvm-mc foo.s -output-asm-variant=1"
263</p>
264
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]265</div>
266
267
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000[diff] [blame]268<!-- *********************************************************************** -->
269<div class="doc_section">
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]270 <a name="externalproj">External Open Source Projects Using LLVM 2.7</a>
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000[diff] [blame]271</div>
272<!-- *********************************************************************** -->
273
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]274<div class="doc_text">
275
276<p>An exciting aspect of LLVM is that it is used as an enabling technology for
277 a lot of other language and tools projects. This section lists some of the
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]278 projects that have already been updated to work with LLVM 2.7.</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]279</div>
280
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000[diff] [blame]281<!--=========================================================================-->
282<div class="doc_subsection">
283<a name="pure">Pure</a>
284</div>
285
286<div class="doc_text">
287<p>
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]288<a href="http://pure-lang.googlecode.com/">Pure</a>
289is an algebraic/functional programming language based on term rewriting.
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000[diff] [blame]290Programs are collections of equations which are used to evaluate expressions in
291a symbolic fashion. Pure offers dynamic typing, eager and lazy evaluation,
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000[diff] [blame]292lexical closures, a hygienic macro system (also based on term rewriting),
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000[diff] [blame]293built-in list and matrix support (including list and matrix comprehensions) and
294an easy-to-use C interface. The interpreter uses LLVM as a backend to
295 JIT-compile Pure programs to fast native code.</p>
296
Chris Lattner477a1fd2010-03-17 17:25:49 +0000[diff] [blame]297<p>Pure versions 0.43 and later have been tested and are known to work with
298LLVM 2.7 (and continue to work with older LLVM releases >= 2.5).</p>
299
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000[diff] [blame]300</div>
301
Chris Lattnerbc31caf2009-02-28 18:58:01 +0000[diff] [blame]302<!--=========================================================================-->
303<div class="doc_subsection">
304<a name="RoadsendPHP">Roadsend PHP</a>
305</div>
306
307<div class="doc_text">
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]308<p>
309<a href="http://code.roadsend.com/rphp">Roadsend PHP</a> (rphp) is an open
Chris Lattnercade8222009-03-02 19:07:24 +0000[diff] [blame]310source implementation of the PHP programming
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]311language that uses LLVM for its optimizer, JIT and static compiler. This is a
Chris Lattner0e464a92010-03-17 04:02:39 +0000[diff] [blame]312reimplementation of an earlier project that is now based on LLVM.
Chris Lattner477a1fd2010-03-17 17:25:49 +0000[diff] [blame]313</p>
Chris Lattnerbc31caf2009-02-28 18:58:01 +0000[diff] [blame]314</div>
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000[diff] [blame]315
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]316<!--=========================================================================-->
317<div class="doc_subsection">
318<a name="UnladenSwallow">Unladen Swallow</a>
319</div>
320
321<div class="doc_text">
322<p>
323<a href="http://code.google.com/p/unladen-swallow/">Unladen Swallow</a> is a
324branch of <a href="http://python.org/">Python</a> intended to be fully
325compatible and significantly faster. It uses LLVM's optimization passes and JIT
Chris Lattnerb5f6feb2010-03-18 06:52:15 +0000[diff] [blame]326compiler.
Chris Lattner0e464a92010-03-17 04:02:39 +0000[diff] [blame]327</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]328</div>
329
330<!--=========================================================================-->
331<div class="doc_subsection">
Chris Lattner8d4bbbe2010-03-29 17:50:39 +0000[diff] [blame]332<a name="tce">TTA-based Codesign Environment (TCE)</a>
333</div>
334
335<div class="doc_text">
336<p>
337<a href="http://tce.cs.tut.fi/">TCE</a> is a toolset for designing
338application-specific processors (ASP) based on the Transport triggered
339architecture (TTA). The toolset provides a complete co-design flow from C/C++
340programs down to synthesizable VHDL and parallel program binaries. Processor
341customization points include the register files, function units, supported
342operations, and the interconnection network.</p>
343
344<p>TCE uses llvm-gcc/Clang and LLVM for C/C++ language support, target
345independent optimizations and also for parts of code generation. It generates
346new LLVM-based code generators "on the fly" for the designed TTA processors and
347loads them in to the compiler backend as runtime libraries to avoid per-target
348recompilation of larger parts of the compiler chain.</p>
349
350</div>
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]351
John Criswellf77cdab2010-04-06 14:52:14 +0000[diff] [blame]352<!--=========================================================================-->
353<div class="doc_subsection">
354<a name="safecode">SAFECode Compiler</a>
355</div>
356
357<div class="doc_text">
358<p>
359<a href="http://safecode.cs.illinois.edu">SAFECode</a> is a memory safe C
360compiler built using LLVM. It takes standard, unannotated C code, analyzes the
361code to ensure that memory accesses and array indexing operations are safe, and
362instruments the code with run-time checks when safety cannot be proven
363statically.
364</p>
365</div>
366
367
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]368<!-- *********************************************************************** -->
369<div class="doc_section">
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]370 <a name="whatsnew">What's New in LLVM 2.7?</a>
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]371</div>
372<!-- *********************************************************************** -->
373
Chris Lattnerf8e0b4e2008-06-08 22:59:35 +0000[diff] [blame]374<div class="doc_text">
375
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]376<p>This release includes a huge number of bug fixes, performance tweaks and
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]377minor improvements. Some of the major improvements and new features are listed
378in this section.
Chris Lattnerf8e0b4e2008-06-08 22:59:35 +0000[diff] [blame]379</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]380
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]381<p>In addition to changes to the code, between LLVM 2.6 and 2.7, a number of
382organization changes have happened:
383</p>
384
385<ul>
386<li>LLVM has a new <a href="http://llvm.org/Logo.html">official Logo</a>!</li>
387
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]388<li>Ted Kremenek and Doug Gregor have stepped forward as <a
389 href="http://llvm.org/docs/DeveloperPolicy.html#owners">Code Owners</a> of the
390 Clang static analyzer and the Clang Frontend, respectively.</li>
Chris Lattner450a31e2010-04-21 06:23:40 +0000[diff] [blame^]391
392<li>LLVM now has an <a href="http://blog.llvm.org">official Blog</a> at
393 <a href="http://blog.llvm.org">http://blog.llvm.org</a>. This is a great way
394 to learn about new LLVM-related features as they are implemented. Several
395 features in this release are already explained on the blog.</li>
396
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]397<li>The LLVM web pages are now checked into the SVN server, in the "www",
398 "www-pubs" and "www-releases" SVN modules. Previously they were hidden in a
399 largely inaccessible old CVS server.</p>
Chris Lattner450a31e2010-04-21 06:23:40 +0000[diff] [blame^]400
401<li><a href="http://llvm.org">llvm.org</a> is now hosted on a new (and much
402 faster) server. It is still graciously hosted at the University of Illinois
403 of Urbana Champaign.</li>
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]404</ul>
Chris Lattnerf8e0b4e2008-06-08 22:59:35 +0000[diff] [blame]405</div>
406
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]407<!--=========================================================================-->
Chris Lattnerea34f642008-06-08 21:34:41 +0000[diff] [blame]408<div class="doc_subsection">
Chris Lattner252b83d2008-02-06 18:00:06 +0000[diff] [blame]409<a name="majorfeatures">Major New Features</a>
410</div>
411
412<div class="doc_text">
413
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]414<p>LLVM 2.7 includes several major new capabilities:</p>
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000[diff] [blame]415
416<ul>
Chris Lattner450a31e2010-04-21 06:23:40 +0000[diff] [blame^]417<li>This release includes initial support for the <a
418 href="http://en.wikipedia.org/wiki/MicroBlaze">MicroBlaze</a> target.
419 MicroBlaze is a soft processor core designed for Xilinx FPGAs.</li>
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]420
Chris Lattner450a31e2010-04-21 06:23:40 +0000[diff] [blame^]421<li>LLVM 2.7 includes a new LLVM IR "extensible metadata" feature. This feature
422 supports many different use cases, including allowing front-end authors to
423 encode source level information into LLVM IR, which is consumed by later
424 language-specific passes. This is a great way to do high-level optimizations
425 like devirtualization, type-based alias analysis, etc. See the <a
426 href="http://blog.llvm.org/2010/04/extensible-metadata-in-llvm-ir.html">
427 Extensible Metadata Blog Post</a> for more information.</li>
428
429<li>LLVM 2.7 encodes <a href="SourceLevelDebugging.html">debug information</a>
430in a completely new way, built on extensible metadata. The new implementation
431is much more memory efficient and paves the way for improvements to optimized
432code debugging experience.</li>
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]433
Chris Lattner450a31e2010-04-21 06:23:40 +0000[diff] [blame^]434<li>LLVM 2.7 now directly supports taking the address of a label and doing an
435 indirect branch through a pointer. This is particularly useful for
436 interpreter loops, and is used to implement the GCC "address of label"
437 extension. For more information, see the <a
438href="http://blog.llvm.org/2010/01/address-of-label-and-indirect-branches.html">
439Address of Label and Indirect Branches in LLVM IR Blog Post</a>.
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]440
Chris Lattner450a31e2010-04-21 06:23:40 +0000[diff] [blame^]441<li>LLVM 2.7 is the first release to start supporting APIs for assembling and
442 disassembling target machine code. These APIs are useful for a variety of
443 low level clients, and are surfaced in the new "enhanced disassembly" API.
444 For more information see the <a
445 href="http://blog.llvm.org/2010/01/x86-disassembler.html">The X86
446 Disassembler Blog Post</a> for more information.</li>
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]447
Chris Lattner450a31e2010-04-21 06:23:40 +0000[diff] [blame^]448<li>LLVM 2.7 includes major parts of the work required by the new MC Project,
449 which aims to rework our handling of low-level machine code. A few targets
450 have been refactored to support it, and work is underway to support a native
451 assembler in LLVM. This work is not complete in LLVM 2.7, but you has made
452 substantially more progress on LLVM mainline. You can read more about this
453 in the <a href="http://blog.llvm.org/2010/04/intro-to-llvm-mc-project.html">
454 Intro to the LLVM MC Project Blog Post</a>.
455</li>
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]456
Chris Lattner8170c102008-02-10 08:18:42 +0000[diff] [blame]457</ul>
Chris Lattnerdc910082010-03-17 06:41:58 +0000[diff] [blame]458
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000[diff] [blame]459</div>
460
Chris Lattner84977642007-09-21 03:54:09 +0000[diff] [blame]461<!--=========================================================================-->
462<div class="doc_subsection">
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]463<a name="coreimprovements">LLVM IR and Core Improvements</a>
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000[diff] [blame]464</div>
465
466<div class="doc_text">
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]467<p>LLVM IR has several new features for better support of new targets and that
468expose new optimization opportunities:</p>
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000[diff] [blame]469
Chris Lattner791f77b2008-06-05 06:25:56 +0000[diff] [blame]470<ul>
Chris Lattner450a31e2010-04-21 06:23:40 +0000[diff] [blame^]471<li>LLVM IR now supports a 16-bit "half float" data type through two new <a
472 href="LangRef.html#int_fp16">intrinsics</a> and APFloat support.</li>
473<li>LLVM IR supports two <a href="LangRef.html#fnattrs">new function
474 attributes</a>: inlinehint and alignstack(n). The former is a hint to the
475 optimizer that a function was declared 'inline' and thus it might be useful
476 to increase the chances the the inliner actually inline it. The later
477 indicates to the code generator that the function diverges from the platform
478 ABI on stack alignment.</li>
479<li>The new <a href="LangRef.html#int_objectsize">llvm.objectsize</a> intrinsic
480 allows the optimizer to infer the sizes of memory objects in some cases.
481 This intrinsic is used to implement the GCC __builtin_object_size
482 extension.</li>
483<li>LLVM 2.7 has pre-alpha support for <a
484 href="http://llvm.org/docs/LangRef.html#t_union">unions in LLVM IR</a>.
485 Unfortuantely, this support is not really usable in 2.7, so if you're
486 interested in pushing it forward, please help contribute to LLVM mainline.</li>
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]487</li>
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000[diff] [blame]488</ul>
Mikhail Glushenkovea65d7d2008-10-13 02:08:34 +0000[diff] [blame]489
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000[diff] [blame]490</div>
491
492<!--=========================================================================-->
493<div class="doc_subsection">
Chris Lattneracce85d2008-02-10 07:46:44 +0000[diff] [blame]494<a name="optimizer">Optimizer Improvements</a>
495</div>
496
497<div class="doc_text">
498
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]499<p>In addition to a large array of minor performance tweaks and bug fixes, this
Chris Lattnerf3013872008-10-13 21:50:36 +0000[diff] [blame]500release includes a few major enhancements and additions to the optimizers:</p>
Chris Lattneracce85d2008-02-10 07:46:44 +0000[diff] [blame]501
502<ul>
503
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]504<li>...</li>
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]505Inliner reuses arrays allocas when inlining multiple callers to reduce stack usage.
506Optimal Edge Profiling?
507Instcombine is now a library, has its own IRBuilder to simplify itself.
508Better code size analysis in loop unswitch, inliner code split out to a new
509 CodeMetrics class for reuse.
510Many changes to the pass ordering for improved optimization effectiveness.
511BasicAA improved to be less dependent on "type safe" pointers, it can now look
512 through bitcasts more aggressively.
513GVN PHI Translation improvements. blog post: http://blog.llvm.org/2009/12/advanced-topics-in-redundant-load.html
514New SCEV AA pass: -scev-aa
515Target data now has notion of 'native' integer data types which optimizations can use.
516Opt now works conservatively if no target data is set (is this fully working?)
517New Analysis/InstructionSimplify.h interface for simplifying instructions that don't exist.
518Jump threading is now much more aggressive at simplifying correlated
519 conditionals and threading blocks with otherwise complex logic. CondProp pass
520 removed (functionality merged into jump threading).
521New SSAUpdater and MachineSSAUpdater classes for unstructured ssa updating,
522 changed jump threading, GVN, etc to use it which simplified them and speed
523 them up.
524
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]525
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]526</ul>
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]527
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]528</div>
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]529
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]530
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]531<!--=========================================================================-->
532<div class="doc_subsection">
533<a name="executionengine">Interpreter and JIT Improvements</a>
534</div>
Chris Lattnerf3013872008-10-13 21:50:36 +0000[diff] [blame]535
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]536<div class="doc_text">
537
538<ul>
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]539<li>The JIT now supports generating debug information, which is compatible with
540the new GDB 7.0 (and later) interfaces for registering debug info for
541dynamically generated code.</li>
542
Jeffrey Yasskin01eba392010-01-29 19:10:38 +0000[diff] [blame]543<li>The JIT now <a
544href="http://llvm.org/viewvc/llvm-project?view=rev&revision=85295">defaults
545to compiling eagerly</a> to avoid a race condition in the lazy JIT.
546Clients that still want the lazy JIT can switch it on by calling
547<tt>ExecutionEngine::DisableLazyCompilation(false)</tt>.</li>
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]548
Jeffrey Yasskin40966a72010-02-11 01:07:39 +0000[diff] [blame]549<li>It is now possible to create more than one JIT instance in the same process.
550These JITs can generate machine code in parallel,
551although <a href="http://llvm.org/docs/ProgrammersManual.html#jitthreading">you
552still have to obey the other threading restrictions</a>.</li>
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]553
Chris Lattner0b832202008-06-08 02:45:07 +0000[diff] [blame]554</ul>
555
556</div>
557
558<!--=========================================================================-->
559<div class="doc_subsection">
Chris Lattner511433e2009-03-02 03:24:11 +0000[diff] [blame]560<a name="codegen">Target Independent Code Generator Improvements</a>
Chris Lattner0b832202008-06-08 02:45:07 +0000[diff] [blame]561</div>
562
563<div class="doc_text">
564
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000[diff] [blame]565<p>We have put a significant amount of work into the code generator
566infrastructure, which allows us to implement more aggressive algorithms and make
567it run faster:</p>
Chris Lattner0b832202008-06-08 02:45:07 +0000[diff] [blame]568
569<ul>
Chris Lattner450a31e2010-04-21 06:23:40 +0000[diff] [blame^]570<li>New instruction selector [blog post?].</li>
Chris Lattner511433e2009-03-02 03:24:11 +0000[diff] [blame]571
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]572Code generator MC'ized except for debug info and EH.
573
574New CodeGen Level CSE
575Combiner-AA improvements, why not on by default?
576Pre-regalloc tail duplication
577New LSR with "full strength reduction" mode. Description?
578Codegen level OptimizeExtsPass pass, takes advantage of x86 subregs.
579Support for the GCC option -fno-schedule-insns
580non-temporal load/store
581MachineSSAUpdater.h
582X86 and XCore supports returning arbitrary return values, returning too many values is
583 supported by returning through a hidden pointer.
584verbose-asm now produces information about spill slots and loop nests
585GHC Haskell ABI / calling conv support.
586Many improvements to debug info
587
588
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]589<li>...</li>
Chris Lattner84977642007-09-21 03:54:09 +0000[diff] [blame]590</ul>
Chris Lattner84977642007-09-21 03:54:09 +0000[diff] [blame]591</div>
592
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]593<!--=========================================================================-->
594<div class="doc_subsection">
595<a name="x86">X86-32 and X86-64 Target Improvements</a>
596</div>
597
598<div class="doc_text">
599<p>New features of the X86 target include:
600</p>
601
602<ul>
Chris Lattner511433e2009-03-02 03:24:11 +0000[diff] [blame]603
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]604<li>PostRA scheduler for X86?</li>
605<li>x86 sibcall / tailcall optimization in CCC mode.</li>
606<li>X86: XMM subreg modeling for extraction of the low element.</li>
Chris Lattner511433e2009-03-02 03:24:11 +0000[diff] [blame]607
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]608</ul>
609
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]610</div>
Chris Lattner84977642007-09-21 03:54:09 +0000[diff] [blame]611
612<!--=========================================================================-->
613<div class="doc_subsection">
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]614<a name="ARM">ARM Target Improvements</a>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000[diff] [blame]615</div>
616
617<div class="doc_text">
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]618<p>New features of the ARM target include:
619</p>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000[diff] [blame]620
621<ul>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000[diff] [blame]622
Chris Lattner450a31e2010-04-21 06:23:40 +0000[diff] [blame^]623<li>The ARM backend now generates instructions in unified assembly syntax.</li>
624
625<li>llvm-gcc now has complete support for the ARM v7 NEON instruction set. This
626 support differs slightly from the GCC implementation. Please see the
627 <a
628href="http://blog.llvm.org/2010/04/arm-advanced-simd-neon-intrinsics-and.html">
629 ARM Advanced SIMD (NEON) Intrinsics and Types in LLVM Blog Post</a> for
630 helpful information if migrating code from GCC to LLVM-GCC.</li>
631
632<li>The ARM and Thumb code generators now using register scavenging for stack
633 object address materialization.(FIXME: WHAT BENEFIT DOES THIS PROVIDE?)</li>
634
635<li>The ARM backend now has good support for ARMv4 targets, and has been tested
636 on StrongARM hardware. Previously, LLVM only supported ARMv4T and
637 newer chips.</li>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]638</ul>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000[diff] [blame]639
Chris Lattnerc441fb82009-03-01 02:30:21 +0000[diff] [blame]640
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]641</div>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000[diff] [blame]642
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]643<!--=========================================================================-->
644<div class="doc_subsection">
645<a name="OtherTarget">Other Target Specific Improvements</a>
646</div>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000[diff] [blame]647
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]648<div class="doc_text">
649<p>New features of other targets include:
650</p>
651
652<ul>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]653<li>...</li>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]654</ul>
655
656</div>
657
658<!--=========================================================================-->
659<div class="doc_subsection">
660<a name="newapis">New Useful APIs</a>
661</div>
662
663<div class="doc_text">
664
665<p>This release includes a number of new APIs that are used internally, which
666 may also be useful for external clients.
667</p>
668
669<ul>
Chris Lattner450a31e2010-04-21 06:23:40 +0000[diff] [blame^]670<li>The llvm/Support/Regex.h header exposes a platform independent regular
671 expression API. Building on this, the <a
672 href="TestingGuide.html#FileCheck">FileCheck</a> utility now supports
673 regular exressions.</li>
674<li>raw_ostream now supports a circular "debug stream" accessed with "dbgs()".
675 By default, this stream works the same way as "errs()", but if you pass
676 <tt>-debug-buffer-size=1000</tt> to opt, the debug stream is capped to a
677 fixed sized circular buffer and the output is printed at the end of the
678 program's execution. This is helpful if you have a long lived compiler
679 process and you're interested in seeing snapshots in time.</li>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]680</ul>
681
682
683</div>
684
685<!--=========================================================================-->
686<div class="doc_subsection">
687<a name="otherimprovements">Other Improvements and New Features</a>
688</div>
689
690<div class="doc_text">
691<p>Other miscellaneous features include:</p>
692
693<ul>
Chris Lattner450a31e2010-04-21 06:23:40 +0000[diff] [blame^]694<li>You can now build LLVM as a big dynamic library (e.g. "libllvm2.7.so"). To
695 get this, configure LLVM with the --enable-shared option.</li>
696
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]697<li>LLVM command line tools now overwrite their output by default, before they
698 would only do this with -f. This makes them more convenient to use, and
699 behave more like standard unix tools.</li>
700
701<li>The opt and llc tools now autodetect whether their input is a .ll or .bc
702 file, and automatically do the right thing. This means you don't need to
703 explicitly use the llvm-as tool for most things.</li>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000[diff] [blame]704</ul>
705
706</div>
707
Chris Lattner77d29b12008-06-05 08:02:49 +0000[diff] [blame]708
709<!--=========================================================================-->
710<div class="doc_subsection">
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]711<a name="changes">Major Changes and Removed Features</a>
712</div>
713
714<div class="doc_text">
715
Chris Lattnereeb4da02008-10-13 22:06:31 +0000[diff] [blame]716<p>If you're already an LLVM user or developer with out-of-tree changes based
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]717on LLVM 2.6, this section lists some "gotchas" that you may run into upgrading
Chris Lattnereeb4da02008-10-13 22:06:31 +0000[diff] [blame]718from the previous release.</p>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]719
720<ul>
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]721
722<li>
723The Andersen's alias analysis ("anders-aa") pass, the Predicate Simplifier
724("predsimplify") pass, the LoopVR pass, the GVNPRE pass, and the random sampling
725profiling ("rsprofiling") passes have all been removed. They were not being
726actively maintained and had substantial problems. If you are interested in
727these components, you are welcome to ressurect them from SVN, fix the
728correctness problems, and resubmit them to mainline.</li>
729
730<li>LLVM now defaults to building most libraries with RTTI turned off, providing
731a code size reduction. Packagers who are interested in building LLVM to support
732plugins that require RTTI information should build with "make REQUIRE_RTTI=1"
733and should read the new <a href="Packaging.html">Advice on Packaging LLVM</a>
734document.</li>
735
Jeffrey Yasskinbc83d062010-02-09 23:03:44 +0000[diff] [blame]736<li>The LLVM interpreter now defaults to <em>not</em> using <tt>libffi</tt> even
737if you have it installed. This makes it more likely that an LLVM built on one
738system will work when copied to a similar system. To use <tt>libffi</tt>,
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]739configure with <tt>--enable-libffi</tt></li>.
Chris Lattnereeb4da02008-10-13 22:06:31 +0000[diff] [blame]740
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]741<li>Debug information uses a completely different representation, an LLVM 2.6
742.bc file should work with LLVM 2.7, but debug info won't come forward.</li>
743
744<li>The LLVM 2.6 (and earlier) "malloc" and "free" instructions got removed,
745 along with LowerAllocations pass. Now you should just use a call to the
746 malloc and free functions in libc. These calls are optimized as well as
747 the old instructions were.</li>
748</ul>
Chris Lattnereeb4da02008-10-13 22:06:31 +0000[diff] [blame]749
750<p>In addition, many APIs have changed in this release. Some of the major LLVM
751API changes are:</p>
752
753<ul>
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]754<li>Just about everything has been converted to use raw_ostream instead of
755 std::ostream.</li>
756<li>llvm/ADT/iterator.h has been removed, just use &lt;iterator&gt;
757 instead.</li>
758<li>The Streams.h file and "DOUT" got removed, use "DEBUG(errs() &lt;&lt; ...);"
759 instead.</li>
Jeffrey Yasskin4fcd6072010-01-28 01:41:20 +0000[diff] [blame]760<li><tt>ModuleProvider</tt> has been <a
761href="http://llvm.org/viewvc/llvm-project?view=rev&revision=94686">removed</a>
762and its methods moved to <tt>Module</tt> and <tt>GlobalValue</tt>.
763Most clients can remove uses of <tt>ExistingModuleProvider</tt>,
764replace <tt>getBitcodeModuleProvider</tt> with
765<tt>getLazyBitcodeModule</tt>, and pass their <tt>Module</tt> to
766functions that used to accept <tt>ModuleProvider</tt>. Clients who
767wrote their own <tt>ModuleProvider</tt>s will need to derive from
768<tt>GVMaterializer</tt> instead and use
769<tt>Module::setMaterializer</tt> to attach it to a
770<tt>Module</tt>.</li>
771
772<li><tt>GhostLinkage</tt> has given up the ghost.
773<tt>GlobalValue</tt>s that have not yet been read from their backing
774storage have the same linkage they will have after being read in.
775Clients must replace calls to
776<tt>GlobalValue::hasNotBeenReadFromBitcode</tt> with
777<tt>GlobalValue::isMaterializable</tt>.</li>
Daniel Dunbar4acdede2010-02-10 04:09:52 +0000[diff] [blame]778
Daniel Dunbarca1c8162010-02-14 01:47:19 +0000[diff] [blame]779<li>The <tt>llvm/Support/DataTypes.h</tt> header has moved
780to <tt>llvm/System/DataTypes.h</tt>.</li>
781
Duncan Sands411432d2010-02-17 17:20:17 +0000[diff] [blame]782<li>The <tt>isInteger</tt>, <tt>isIntOrIntVector</tt>, <tt>isFloatingPoint</tt>,
783<tt>isFPOrFPVector</tt> and <tt>isFPOrFPVector</tt> methods have been renamed
784<tt>isIntegerTy</tt>, <tt>isIntOrIntVectorTy</tt>, <tt>isFloatingPointTy</tt>,
785<tt>isFPOrFPVectorTy</tt> and <tt>isFPOrFPVectorTy</tt> respectively.</li>
Devang Patelb34dd132008-10-14 20:03:43 +0000[diff] [blame]786</ul>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]787
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]788</div>
789
790
791
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]792<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]793<div class="doc_section">
794 <a name="portability">Portability and Supported Platforms</a>
795</div>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]796<!-- *********************************************************************** -->
797
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]798<div class="doc_text">
799
John Criswell0b5b5e92004-12-08 20:35:47 +0000[diff] [blame]800<p>LLVM is known to work on the following platforms:</p>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]801
802<ul>
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000[diff] [blame]803<li>Intel and AMD machines (IA32, X86-64, AMD64, EMT-64) running Red Hat
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]804 Linux, Fedora Core, FreeBSD and AuroraUX (and probably other unix-like
805 systems).</li>
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000[diff] [blame]806<li>PowerPC and X86-based Mac OS X systems, running 10.3 and above in 32-bit
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]807 and 64-bit modes.</li>
Chris Lattner252b83d2008-02-06 18:00:06 +0000[diff] [blame]808<li>Intel and AMD machines running on Win32 using MinGW libraries (native).</li>
Chris Lattner57a460e2007-05-23 04:39:32 +0000[diff] [blame]809<li>Intel and AMD machines running on Win32 with the Cygwin libraries (limited
810 support is available for native builds with Visual C++).</li>
Chris Lattner7e23d6e2009-10-16 16:30:58 +0000[diff] [blame]811<li>Sun x86 and AMD64 machines running Solaris 10, OpenSolaris 0906.</li>
John Criswell9321fa82005-05-13 20:28:15 +0000[diff] [blame]812<li>Alpha-based machines running Debian GNU/Linux.</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]813</ul>
814
Chris Lattnerbc5786b2008-06-05 06:57:39 +0000[diff] [blame]815<p>The core LLVM infrastructure uses GNU autoconf to adapt itself
Brian Gaekeb0fd7612004-05-09 05:28:35 +0000[diff] [blame]816to the machine and operating system on which it is built. However, minor
817porting may be required to get LLVM to work on new platforms. We welcome your
818portability patches and reports of successful builds or error messages.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]819
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]820</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]821
822<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]823<div class="doc_section">
824 <a name="knownproblems">Known Problems</a>
825</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]826<!-- *********************************************************************** -->
827
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]828<div class="doc_text">
829
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000[diff] [blame]830<p>This section contains significant known problems with the LLVM system,
Chris Lattnere18b32e2008-11-10 05:40:34 +0000[diff] [blame]831listed by component. If you run into a problem, please check the <a
Chris Lattnerc463b272005-10-29 07:07:09 +0000[diff] [blame]832href="http://llvm.org/bugs/">LLVM bug database</a> and submit a bug if
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]833there isn't already one.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]834
Chris Lattner477a1fd2010-03-17 17:25:49 +0000[diff] [blame]835<ul>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]836<li>LLVM will not correctly compile on Solaris and/or OpenSolaris
837using the stock GCC 3.x.x series 'out the box',
Chris Lattner554ee4a2009-11-03 21:50:09 +0000[diff] [blame]838See: <a href="GettingStarted.html#brokengcc">Broken versions of GCC and other tools</a>.
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]839However, A <a href="http://pkg.auroraux.org/GCC">Modern GCC Build</a>
840for x86/x86-64 has been made available from the third party AuroraUX Project
841that has been meticulously tested for bootstrapping LLVM &amp; Clang.</li>
842</ul>
843
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]844</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]845
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]846<!-- ======================================================================= -->
847<div class="doc_subsection">
848 <a name="experimental">Experimental features included with this release</a>
849</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]850
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]851<div class="doc_text">
852
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]853<p>The following components of this LLVM release are either untested, known to
854be broken or unreliable, or are in early development. These components should
855not be relied on, and bugs should not be filed against them, but they may be
856useful to some people. In particular, if you would like to work on one of these
Chris Lattner2b659ef2008-02-12 06:29:45 +0000[diff] [blame]857components, please contact us on the <a
858href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev list</a>.</p>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]859
860<ul>
Wesley Peck7c4a1212010-03-18 14:31:30 +0000[diff] [blame]861<li>The MSIL, Alpha, SPU, MIPS, PIC16, Blackfin, MSP430, SystemZ and MicroBlaze
862 backends are experimental.</li>
Bill Wendling99dac472009-03-02 07:54:14 +0000[diff] [blame]863<li>The <tt>llc</tt> "<tt>-filetype=asm</tt>" (the default) is the only
Chris Lattnerc66bfef2010-03-17 04:41:49 +0000[diff] [blame]864 supported value for this option. The MachO writer is experimental, and
865 works much better in mainline SVN.</li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]866</ul>
867
868</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]869
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]870<!-- ======================================================================= -->
871<div class="doc_subsection">
Chris Lattner26299222006-11-18 07:51:14 +0000[diff] [blame]872 <a name="x86-be">Known problems with the X86 back-end</a>
John Criswellc0c186d2005-11-08 21:11:33 +0000[diff] [blame]873</div>
874
875<div class="doc_text">
876
877<ul>
Anton Korobeynikova6094be2008-06-08 10:24:13 +0000[diff] [blame]878 <li>The X86 backend does not yet support
879 all <a href="http://llvm.org/PR879">inline assembly that uses the X86
880 floating point stack</a>. It supports the 'f' and 't' constraints, but not
881 'u'.</li>
Chris Lattnere6e1b352008-06-08 21:19:07 +0000[diff] [blame]882 <li>The X86 backend generates inefficient floating point code when configured
883 to generate code for systems that don't have SSE2.</li>
Duncan Sands47eff2b2008-06-08 19:38:43 +0000[diff] [blame]884 <li>Win64 code generation wasn't widely tested. Everything should work, but we
John Criswell524a5dd2009-03-02 15:28:15 +0000[diff] [blame]885 expect small issues to happen. Also, llvm-gcc cannot build the mingw64
886 runtime currently due
Anton Korobeynikova6094be2008-06-08 10:24:13 +0000[diff] [blame]887 to <a href="http://llvm.org/PR2255">several</a>
John Criswell524a5dd2009-03-02 15:28:15 +0000[diff] [blame]888 <a href="http://llvm.org/PR2257">bugs</a> and due to lack of support for
889 the
890 'u' inline assembly constraint and for X87 floating point inline assembly.</li>
Dan Gohman8207ba92008-06-08 23:05:11 +0000[diff] [blame]891 <li>The X86-64 backend does not yet support the LLVM IR instruction
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]892 <tt>va_arg</tt>. Currently, the llvm-gcc and front-ends support variadic
Dan Gohman8207ba92008-06-08 23:05:11 +0000[diff] [blame]893 argument constructs on X86-64 by lowering them manually.</li>
Chris Lattner26299222006-11-18 07:51:14 +0000[diff] [blame]894</ul>
895
896</div>
897
898<!-- ======================================================================= -->
899<div class="doc_subsection">
900 <a name="ppc-be">Known problems with the PowerPC back-end</a>
901</div>
902
903<div class="doc_text">
904
905<ul>
Nicolas Geoffraye4285dc2007-05-15 09:21:28 +0000[diff] [blame]906<li>The Linux PPC32/ABI support needs testing for the interpreter and static
Chris Lattner57a460e2007-05-23 04:39:32 +0000[diff] [blame]907compilation, and lacks support for debug information.</li>
Chris Lattner26299222006-11-18 07:51:14 +0000[diff] [blame]908</ul>
909
910</div>
911
912<!-- ======================================================================= -->
913<div class="doc_subsection">
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000[diff] [blame]914 <a name="arm-be">Known problems with the ARM back-end</a>
915</div>
916
917<div class="doc_text">
918
919<ul>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]920<li>Support for the Advanced SIMD (Neon) instruction set is still incomplete
921and not well tested. Some features may not work at all, and the code quality
922may be poor in some cases.</li>
Chris Lattner57a460e2007-05-23 04:39:32 +0000[diff] [blame]923<li>Thumb mode works only on ARMv6 or higher processors. On sub-ARMv6
Duncan Sandsc90d68b2007-09-26 15:59:54 +0000[diff] [blame]924processors, thumb programs can crash or produce wrong
Chris Lattner57a460e2007-05-23 04:39:32 +0000[diff] [blame]925results (<a href="http://llvm.org/PR1388">PR1388</a>).</li>
John Criswell524a5dd2009-03-02 15:28:15 +0000[diff] [blame]926<li>Compilation for ARM Linux OABI (old ABI) is supported but not fully tested.
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000[diff] [blame]927</li>
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000[diff] [blame]928</ul>
929
930</div>
931
932<!-- ======================================================================= -->
933<div class="doc_subsection">
Chris Lattner26299222006-11-18 07:51:14 +0000[diff] [blame]934 <a name="sparc-be">Known problems with the SPARC back-end</a>
935</div>
936
937<div class="doc_text">
938
939<ul>
John Criswell524a5dd2009-03-02 15:28:15 +0000[diff] [blame]940<li>The SPARC backend only supports the 32-bit SPARC ABI (-m32); it does not
Chris Lattner26299222006-11-18 07:51:14 +0000[diff] [blame]941 support the 64-bit SPARC ABI (-m64).</li>
942</ul>
943
944</div>
945
946<!-- ======================================================================= -->
947<div class="doc_subsection">
Bruno Cardoso Lopesb7e1a4f2008-10-25 14:56:26 +0000[diff] [blame]948 <a name="mips-be">Known problems with the MIPS back-end</a>
949</div>
950
951<div class="doc_text">
952
953<ul>
Bruno Cardoso Lopesb7e1a4f2008-10-25 14:56:26 +0000[diff] [blame]954<li>64-bit MIPS targets are not supported yet.</li>
955</ul>
956
957</div>
958
959<!-- ======================================================================= -->
960<div class="doc_subsection">
Chris Lattner26299222006-11-18 07:51:14 +0000[diff] [blame]961 <a name="alpha-be">Known problems with the Alpha back-end</a>
962</div>
963
964<div class="doc_text">
965
966<ul>
967
968<li>On 21164s, some rare FP arithmetic sequences which may trap do not have the
969appropriate nops inserted to ensure restartability.</li>
970
John Criswellc0c186d2005-11-08 21:11:33 +0000[diff] [blame]971</ul>
972</div>
973
Chris Lattner26299222006-11-18 07:51:14 +0000[diff] [blame]974<!-- ======================================================================= -->
975<div class="doc_subsection">
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000[diff] [blame]976 <a name="c-be">Known problems with the C back-end</a>
Chris Lattner26299222006-11-18 07:51:14 +0000[diff] [blame]977</div>
978
979<div class="doc_text">
980
981<ul>
Chris Lattner5733b272008-06-05 06:35:40 +0000[diff] [blame]982<li><a href="http://llvm.org/PR802">The C backend has only basic support for
983 inline assembly code</a>.</li>
Chris Lattner725a0d82007-09-26 06:01:35 +0000[diff] [blame]984<li><a href="http://llvm.org/PR1658">The C backend violates the ABI of common
985 C++ programs</a>, preventing intermixing between C++ compiled by the CBE and
Gabor Greif4906abe2009-03-02 12:02:51 +0000[diff] [blame]986 C++ code compiled with <tt>llc</tt> or native compilers.</li>
Duncan Sandsf74c0cc2008-02-10 13:40:55 +0000[diff] [blame]987<li>The C backend does not support all exception handling constructs.</li>
Duncan Sands50723a92009-02-25 11:51:54 +0000[diff] [blame]988<li>The C backend does not support arbitrary precision integers.</li>
Chris Lattner26299222006-11-18 07:51:14 +0000[diff] [blame]989</ul>
990
991</div>
John Criswellc0c186d2005-11-08 21:11:33 +0000[diff] [blame]992
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]993
994<!-- ======================================================================= -->
995<div class="doc_subsection">
Chris Lattnerc66bfef2010-03-17 04:41:49 +0000[diff] [blame]996 <a name="c-fe">Known problems with the llvm-gcc C and C++ front-end</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]997</div>
Chris Lattner47588f92003-10-02 05:07:23 +0000[diff] [blame]998
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]999<div class="doc_text">
Chris Lattnerc5d658a2006-03-03 00:34:26 +0000[diff] [blame]1000
Chris Lattner5733b272008-06-05 06:35:40 +0000[diff] [blame]1001<p>The only major language feature of GCC not supported by llvm-gcc is
1002 the <tt>__builtin_apply</tt> family of builtins. However, some extensions
1003 are only supported on some targets. For example, trampolines are only
Duncan Sands27aff872008-06-08 20:18:35 +0000[diff] [blame]1004 supported on some targets (these are used when you take the address of a
1005 nested function).</p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1006
Chris Lattner5733b272008-06-05 06:35:40 +0000[diff] [blame]1007<p>If you run into GCC extensions which are not supported, please let us know.
1008</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]1009
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1010</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]1011
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1012<!-- ======================================================================= -->
1013<div class="doc_subsection">
Chris Lattner1eb4df62008-10-30 03:58:13 +0000[diff] [blame]1014 <a name="fortran-fe">Known problems with the llvm-gcc Fortran front-end</a>
1015</div>
1016
1017<div class="doc_text">
Gabor Greifba10fe02008-11-04 21:50:59 +0000[diff] [blame]1018<ul>
Chris Lattner1eb4df62008-10-30 03:58:13 +0000[diff] [blame]1019<li>Fortran support generally works, but there are still several unresolved bugs
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]1020 in <a href="http://llvm.org/bugs/">Bugzilla</a>. Please see the
1021 tools/gfortran component for details.</li>
Gabor Greifba10fe02008-11-04 21:50:59 +0000[diff] [blame]1022</ul>
Chris Lattner1eb4df62008-10-30 03:58:13 +0000[diff] [blame]1023</div>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1024
Chris Lattner2b659ef2008-02-12 06:29:45 +0000[diff] [blame]1025<!-- ======================================================================= -->
1026<div class="doc_subsection">
Chris Lattner5733b272008-06-05 06:35:40 +0000[diff] [blame]1027 <a name="ada-fe">Known problems with the llvm-gcc Ada front-end</a>
Chris Lattner2b659ef2008-02-12 06:29:45 +0000[diff] [blame]1028</div>
1029
1030<div class="doc_text">
John Criswell524a5dd2009-03-02 15:28:15 +0000[diff] [blame]1031The llvm-gcc 4.2 Ada compiler works fairly well; however, this is not a mature
1032technology, and problems should be expected.
Chris Lattner2b659ef2008-02-12 06:29:45 +0000[diff] [blame]1033<ul>
Duncan Sands27aff872008-06-08 20:18:35 +0000[diff] [blame]1034<li>The Ada front-end currently only builds on X86-32. This is mainly due
John Criswell524a5dd2009-03-02 15:28:15 +0000[diff] [blame]1035to lack of trampoline support (pointers to nested functions) on other platforms.
1036However, it <a href="http://llvm.org/PR2006">also fails to build on X86-64</a>
Chris Lattner2b659ef2008-02-12 06:29:45 +0000[diff] [blame]1037which does support trampolines.</li>
1038<li>The Ada front-end <a href="http://llvm.org/PR2007">fails to bootstrap</a>.
Duncan Sands326a4982009-02-25 11:59:06 +0000[diff] [blame]1039This is due to lack of LLVM support for <tt>setjmp</tt>/<tt>longjmp</tt> style
1040exception handling, which is used internally by the compiler.
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]1041Workaround: configure with <tt>--disable-bootstrap</tt>.</li>
Duncan Sands978bcee2008-10-13 17:27:23 +0000[diff] [blame]1042<li>The c380004, <a href="http://llvm.org/PR2010">c393010</a>
1043and <a href="http://llvm.org/PR2421">cxg2021</a> ACATS tests fail
Duncan Sands326a4982009-02-25 11:59:06 +0000[diff] [blame]1044(c380004 also fails with gcc-4.2 mainline).
1045If the compiler is built with checks disabled then <a href="http://llvm.org/PR2010">c393010</a>
1046causes the compiler to go into an infinite loop, using up all system memory.</li>
Duncan Sandsdd3e6722009-03-02 16:35:57 +0000[diff] [blame]1047<li>Some GCC specific Ada tests continue to crash the compiler.</li>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]1048<li>The <tt>-E</tt> binder option (exception backtraces)
Chris Lattner2b659ef2008-02-12 06:29:45 +0000[diff] [blame]1049<a href="http://llvm.org/PR1982">does not work</a> and will result in programs
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]1050crashing if an exception is raised. Workaround: do not use <tt>-E</tt>.</li>
Chris Lattner2b659ef2008-02-12 06:29:45 +0000[diff] [blame]1051<li>Only discrete types <a href="http://llvm.org/PR1981">are allowed to start
1052or finish at a non-byte offset</a> in a record. Workaround: do not pack records
1053or use representation clauses that result in a field of a non-discrete type
1054starting or finishing in the middle of a byte.</li>
Chris Lattnere6e1b352008-06-08 21:19:07 +0000[diff] [blame]1055<li>The <tt>lli</tt> interpreter <a href="http://llvm.org/PR2009">considers
1056'main' as generated by the Ada binder to be invalid</a>.
1057Workaround: hand edit the file to use pointers for <tt>argv</tt> and
1058<tt>envp</tt> rather than integers.</li>
1059<li>The <tt>-fstack-check</tt> option <a href="http://llvm.org/PR2008">is
1060ignored</a>.</li>
Chris Lattner2b659ef2008-02-12 06:29:45 +0000[diff] [blame]1061</ul>
1062</div>
1063
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]1064<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1065<div class="doc_section">
1066 <a name="additionalinfo">Additional Information</a>
1067</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]1068<!-- *********************************************************************** -->
1069
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1070<div class="doc_text">
1071
Chris Lattner416db102005-05-16 17:13:10 +0000[diff] [blame]1072<p>A wide variety of additional information is available on the <a
Chris Lattnerb4b0ce72007-05-18 00:44:29 +0000[diff] [blame]1073href="http://llvm.org">LLVM web page</a>, in particular in the <a
1074href="http://llvm.org/docs/">documentation</a> section. The web page also
Reid Spencer669ed452007-07-09 08:04:31 +0000[diff] [blame]1075contains versions of the API documentation which is up-to-date with the
1076Subversion version of the source code.
Misha Brukman109d9e82005-03-30 19:14:24 +0000[diff] [blame]1077You can access versions of these documents specific to this release by going
1078into the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]1079
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1080<p>If you have any questions or comments about LLVM, please feel free to contact
Chris Lattnerc463b272005-10-29 07:07:09 +0000[diff] [blame]1081us via the <a href="http://llvm.org/docs/#maillist"> mailing
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]1082lists</a>.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]1083
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1084</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]1085
1086<!-- *********************************************************************** -->
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]1087
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1088<hr>
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]1089<address>
Misha Brukman38847d52003-12-21 22:53:21 +0000[diff] [blame]1090 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
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Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]1094
Chris Lattnerb4b0ce72007-05-18 00:44:29 +0000[diff] [blame]1095 <a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1096 Last modified: $Date$
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]1097</address>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]1098
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1099</body>
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