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gerrit-public.fairphone.software / fp2-dev / platform / external / llvm / 0b94b5f52b11092a69267159dfe0df3acdfcabd7 / . / docs / ReleaseNotes.html
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Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]7 <title>LLVM 3.1 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
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]11<h1>LLVM 3.1 Release Notes</h1>
Mikhail Glushenkovea65d7d2008-10-13 02:08:34 +0000[diff] [blame]12
Jakub Staszakf8de54f2011-12-06 23:33:07 +0000[diff] [blame]13<div>
14<img style="float:right" src="http://llvm.org/img/DragonSmall.png"
15 width="136" height="136" alt="LLVM Dragon Logo">
16</div>
Chris Lattner0e464a92010-03-17 04:02:39 +0000[diff] [blame]17
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]18<ol>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]19 <li><a href="#intro">Introduction</a></li>
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]20 <li><a href="#subproj">Sub-project Status Update</a></li>
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]21 <li><a href="#externalproj">External Projects Using LLVM 3.1</a></li>
22 <li><a href="#whatsnew">What's New in LLVM?</a></li>
Chris Lattner4b538b92004-04-30 22:17:12 +0000[diff] [blame]23 <li><a href="GettingStarted.html">Installation Instructions</a></li>
Dan Gohman44aa9212008-10-14 16:23:02 +0000[diff] [blame]24 <li><a href="#knownproblems">Known Problems</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]25 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]26</ol>
27
Chris Lattner7911ce22004-05-23 21:07:27 +0000[diff] [blame]28<div class="doc_author">
NAKAMURA Takumib9a33632011-04-09 02:13:37 +0000[diff] [blame]29 <p>Written by the <a href="http://llvm.org/">LLVM Team</a></p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]30</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]31
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]32<h1 style="color:red">These are in-progress notes for the upcoming LLVM 3.1
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]33release.<br>
34You may prefer the
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]35<a href="http://llvm.org/releases/3.0/docs/ReleaseNotes.html">LLVM 3.0
Dan Gohmanb44f6c62010-05-03 23:51:05 +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<!-- *********************************************************************** -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]39<h2>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]40 <a name="intro">Introduction</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]41</h2>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]42<!-- *********************************************************************** -->
43
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]44<div>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]45
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]46<p>This document contains the release notes for the LLVM Compiler
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]47 Infrastructure, release 3.1. Here we describe the status of LLVM, including
Chris Lattner1ab8ce92011-11-27 18:47:37 +0000[diff] [blame]48 major improvements from the previous release, improvements in various
49 subprojects of LLVM, and some of the current users of the code.
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]50 All LLVM releases may be downloaded from
51 the <a href="http://llvm.org/releases/">LLVM releases web site</a>.</p>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]52
Chris Lattner7506b1d2004-12-07 08:04:13 +0000[diff] [blame]53<p>For more information about LLVM, including information about the latest
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]54 release, please check out the <a href="http://llvm.org/">main LLVM web
55 site</a>. If you have questions or comments,
56 the <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM
57 Developer's Mailing List</a> is a good place to send them.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]58
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]59<p>Note that if you are reading this file from a Subversion checkout or the main
60 LLVM web page, this document applies to the <i>next</i> release, not the
61 current one. To see the release notes for a specific release, please see the
62 <a href="http://llvm.org/releases/">releases page</a>.</p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]63
64</div>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame]65
66
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]67<!-- *********************************************************************** -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]68<h2>
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]69 <a name="subproj">Sub-project Status Update</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]70</h2>
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]71<!-- *********************************************************************** -->
Chris Lattnerea34f642008-06-08 21:34:41 +0000[diff] [blame]72
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]73<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]74
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]75<p>The LLVM 3.1 distribution currently consists of code from the core LLVM
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]76 repository (which roughly includes the LLVM optimizers, code generators and
Chris Lattnerc343e312011-11-10 20:15:40 +0000[diff] [blame]77 supporting tools), and the Clang repository. In
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]78 addition to this code, the LLVM Project includes other sub-projects that are
79 in development. Here we include updates on these subprojects.</p>
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]80
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]81<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]82<h3>
Chris Lattnerfb97b2d2008-10-13 18:11:54 +0000[diff] [blame]83<a name="clang">Clang: C/C++/Objective-C Frontend Toolkit</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]84</h3>
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]85
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]86<div>
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]87
Chris Lattner095539f2010-04-26 17:42:18 +0000[diff] [blame]88<p><a href="http://clang.llvm.org/">Clang</a> is an LLVM front end for the C,
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]89 C++, and Objective-C languages. Clang aims to provide a better user
90 experience through expressive diagnostics, a high level of conformance to
91 language standards, fast compilation, and low memory use. Like LLVM, Clang
92 provides a modular, library-based architecture that makes it suitable for
93 creating or integrating with other development tools. Clang is considered a
94 production-quality compiler for C, Objective-C, C++ and Objective-C++ on x86
Chris Lattner1ab8ce92011-11-27 18:47:37 +0000[diff] [blame]95 (32- and 64-bit), and for Darwin/ARM targets.</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]96
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]97<p>In the LLVM 3.1 time-frame, the Clang team has made many improvements:</p>
Douglas Gregorba087df2011-10-15 00:48:01 +0000[diff] [blame]98<ul>
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]99 <li>...</li>
Douglas Gregorba087df2011-10-15 00:48:01 +0000[diff] [blame]100</ul>
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]101
102 <p>For more details about the changes to Clang since the 2.9 release, see the
Chandler Carruthcc966de2011-11-29 00:32:43 +0000[diff] [blame]103<a href="http://clang.llvm.org/docs/ReleaseNotes.html">Clang release notes</a>
104</p>
Douglas Gregorba087df2011-10-15 00:48:01 +0000[diff] [blame]105
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame]106
Duncan Sandsf3ba7af2011-04-06 08:07:40 +0000[diff] [blame]107<p>If Clang rejects your code but another compiler accepts it, please take a
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]108 look at the <a href="http://clang.llvm.org/compatibility.html">language
109 compatibility</a> guide to make sure this is not intentional or a known
110 issue.</p>
Bill Wendling741748a2008-10-27 09:27:33 +0000[diff] [blame]111
Chris Lattnerfb97b2d2008-10-13 18:11:54 +0000[diff] [blame]112</div>
113
114<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]115<h3>
Duncan Sands528a5102011-04-04 11:09:08 +0000[diff] [blame]116<a name="dragonegg">DragonEgg: GCC front-ends, LLVM back-end</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]117</h3>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]118
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]119<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]120<p><a href="http://dragonegg.llvm.org/">DragonEgg</a> is a
121 <a href="http://gcc.gnu.org/wiki/plugins">gcc plugin</a> that replaces GCC's
Duncan Sands77352c92011-11-10 18:44:29 +0000[diff] [blame]122 optimizers and code generators with LLVM's. It works with gcc-4.5 or gcc-4.6,
123 targets the x86-32 and x86-64 processor families, and has been successfully
124 used on the Darwin, FreeBSD, KFreeBSD, Linux and OpenBSD platforms. It fully
125 supports Ada, C, C++ and Fortran. It has partial support for Go, Java, Obj-C
126 and Obj-C++.</p>
Duncan Sands749fd832010-04-02 09:23:15 +0000[diff] [blame]127
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]128<p>The 3.1 release has the following notable changes:</p>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]129
Chris Lattner1ab8ce92011-11-27 18:47:37 +0000[diff] [blame]130 <ul>
Duncan Sands77352c92011-11-10 18:44:29 +0000[diff] [blame]131
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]132 <li>...</li>
Duncan Sands77352c92011-11-10 18:44:29 +0000[diff] [blame]133
Duncan Sands4b1da2b2010-09-30 17:37:34 +0000[diff] [blame]134</ul>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]135
136</div>
137
Chris Lattner75547712010-10-03 23:49:06 +0000[diff] [blame]138<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]139<h3>
Chris Lattner75547712010-10-03 23:49:06 +0000[diff] [blame]140<a name="compiler-rt">compiler-rt: Compiler Runtime Library</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]141</h3>
Chris Lattner75547712010-10-03 23:49:06 +0000[diff] [blame]142
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]143<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]144
145<p>The new LLVM <a href="http://compiler-rt.llvm.org/">compiler-rt project</a>
146 is a simple library that provides an implementation of the low-level
147 target-specific hooks required by code generation and other runtime
148 components. For example, when compiling for a 32-bit target, converting a
149 double to a 64-bit unsigned integer is compiled into a runtime call to the
150 "__fixunsdfdi" function. The compiler-rt library provides highly optimized
151 implementations of this and other low-level routines (some are 3x faster than
152 the equivalent libgcc routines).</p>
Chris Lattner75547712010-10-03 23:49:06 +0000[diff] [blame]153
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]154<p>....</p>
Chris Lattner75547712010-10-03 23:49:06 +0000[diff] [blame]155
156</div>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]157
158<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]159<h3>
Chris Lattnere07043c2010-09-29 05:30:03 +0000[diff] [blame]160<a name="lldb">LLDB: Low Level Debugger</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]161</h3>
Chris Lattnere07043c2010-09-29 05:30:03 +0000[diff] [blame]162
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]163<div>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame]164
Chris Lattner9e896712011-11-27 18:53:41 +0000[diff] [blame]165<p>LLDB is a ground-up implementation of a command line debugger, as well as a
166 debugger API that can be used from other applications. LLDB makes use of the
167 Clang parser to provide high-fidelity expression parsing (particularly for
168 C++) and uses the LLVM JIT for target support.</p>
Chris Lattnere07043c2010-09-29 05:30:03 +0000[diff] [blame]169
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]170<p>...</p>
Chris Lattnere07043c2010-09-29 05:30:03 +0000[diff] [blame]171
172</div>
173
174<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]175<h3>
Chris Lattnere07043c2010-09-29 05:30:03 +0000[diff] [blame]176<a name="libc++">libc++: C++ Standard Library</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]177</h3>
Chris Lattnere07043c2010-09-29 05:30:03 +0000[diff] [blame]178
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]179<div>
Chris Lattnere07043c2010-09-29 05:30:03 +0000[diff] [blame]180
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]181<p>Like compiler_rt, libc++ is now <a href="DeveloperPolicy.html#license">dual
182 licensed</a> under the MIT and UIUC license, allowing it to be used more
183 permissively.</p>
Chris Lattnere07043c2010-09-29 05:30:03 +0000[diff] [blame]184
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]185<p>...</p>
David Chisnall553284e2011-11-26 10:56:17 +0000[diff] [blame]186
Chris Lattnere07043c2010-09-29 05:30:03 +0000[diff] [blame]187</div>
188
Chris Lattner3d6a80a2011-04-07 03:08:22 +0000[diff] [blame]189<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]190<h3>
Chris Lattner3d6a80a2011-04-07 03:08:22 +0000[diff] [blame]191<a name="vmkit">VMKit</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]192</h3>
Chris Lattner3d6a80a2011-04-07 03:08:22 +0000[diff] [blame]193
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]194<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]195
Nicolas Geoffray54d5df92011-11-10 23:37:56 +0000[diff] [blame]196 <p>The <a href="http://vmkit.llvm.org/">VMKit project</a> is an
197 implementation of a Java Virtual Machine (Java VM or JVM) that uses LLVM for
198 static and just-in-time compilation.
199
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]200 <p>In the LLVM 3.1 time-frame, VMKit has had significant improvements on both
Nicolas Geoffray54d5df92011-11-10 23:37:56 +0000[diff] [blame]201 runtime and startup performance:</p>
202
203 <ul>
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]204 <li>...</li>
Nicolas Geoffray54d5df92011-11-10 23:37:56 +0000[diff] [blame]205 </ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]206
Chris Lattner3d6a80a2011-04-07 03:08:22 +0000[diff] [blame]207</div>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame]208
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]209</div>
Daniel Dunbar97b01a82010-10-04 17:39:47 +0000[diff] [blame]210
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000[diff] [blame]211<!-- *********************************************************************** -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]212<h2>
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]213 <a name="externalproj">External Open Source Projects Using LLVM 3.1</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]214</h2>
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000[diff] [blame]215<!-- *********************************************************************** -->
216
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]217<div>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]218
219<p>An exciting aspect of LLVM is that it is used as an enabling technology for
220 a lot of other language and tools projects. This section lists some of the
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]221 projects that have already been updated to work with LLVM 3.1.</p>
Chris Lattner75547712010-10-03 23:49:06 +0000[diff] [blame]222
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]223 ... to be filled in right before the release ...
Bill Wendling644ce532011-10-26 09:25:01 +0000[diff] [blame]224
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]225</div>
226
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]227<!-- *********************************************************************** -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]228<h2>
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]229 <a name="whatsnew">What's New in LLVM 3.1?</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]230</h2>
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]231<!-- *********************************************************************** -->
232
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]233<div>
Chris Lattnerf8e0b4e2008-06-08 22:59:35 +0000[diff] [blame]234
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]235<p>This release includes a huge number of bug fixes, performance tweaks and
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]236 minor improvements. Some of the major improvements and new features are
237 listed in this section.</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]238
Chris Lattner914ce462010-04-22 06:28:20 +0000[diff] [blame]239<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]240<h3>
Chris Lattner252b83d2008-02-06 18:00:06 +0000[diff] [blame]241<a name="majorfeatures">Major New Features</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]242</h3>
Chris Lattner252b83d2008-02-06 18:00:06 +0000[diff] [blame]243
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]244<div>
Chris Lattner252b83d2008-02-06 18:00:06 +0000[diff] [blame]245
Chris Lattner1ab8ce92011-11-27 18:47:37 +0000[diff] [blame]246 <!-- Features that need text if they're finished for 3.1:
247 ARM EHABI
248 combiner-aa?
249 strong phi elim
250 loop dependence analysis
251 CorrelatedValuePropagation
252 lib/Transforms/IPO/MergeFunctions.cpp => consider for 3.1.
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]253 Integrated assembler on by default for arm/thumb?
254
Chris Lattner1ab8ce92011-11-27 18:47:37 +0000[diff] [blame]255 -->
256
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]257 <!-- Near dead:
Chris Lattnerdec23b62011-11-15 22:13:27 +0000[diff] [blame]258 Analysis/RegionInfo.h + Dom Frontiers
259 SparseBitVector: used in LiveVar.
Chris Lattner5a1731d2011-11-27 08:32:32 +0000[diff] [blame]260 llvm/lib/Archive - replace with lib object?
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]261 -->
Chris Lattner6a007d12011-11-25 20:33:27 +0000[diff] [blame]262
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]263<p>LLVM 3.1 includes several major changes and big features:</p>
Bill Wendlingbc5f6dd2011-10-26 18:33:01 +0000[diff] [blame]264
Chris Lattner791f77b2008-06-05 06:25:56 +0000[diff] [blame]265<ul>
Evan Cheng28681862011-12-14 22:57:45 +0000[diff] [blame]266 <li><a href="../tools/clang/docs/AddressSanitizer.html">AddressSanitizer</a>,
267 a fast memory error detector.</li>
268 <li><a href="CodeGenerator.html#machineinstrbundle">MachineInstr Bundles</a>,
269 Support to model instruction bundling / packing.</li>
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]270 <li>....</li>
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000[diff] [blame]271</ul>
Mikhail Glushenkovea65d7d2008-10-13 02:08:34 +0000[diff] [blame]272
Bill Wendlingbc5f6dd2011-10-26 18:33:01 +0000[diff] [blame]273</div>
274
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame]275
Chris Lattner4f0fe432011-11-27 19:26:30 +0000[diff] [blame]276<!--=========================================================================-->
277<h3>
278<a name="coreimprovements">LLVM IR and Core Improvements</a>
279</h3>
280
281<div>
282
283<p>LLVM IR has several new features for better support of new targets and that
284 expose new optimization opportunities:</p>
285
Chris Lattner064caf92011-11-27 21:30:28 +0000[diff] [blame]286 <ul>
Dan Gohmaneb4c70b2011-12-20 01:10:56 +0000[diff] [blame]287 <li>IR support for half float</li>
Nadav Rotem75597662011-12-20 08:02:50 +0000[diff] [blame]288 <li>IR support for vectors of pointers, including vector GEPs.</li>
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]289 <li>....</li>
Chris Lattner064caf92011-11-27 21:30:28 +0000[diff] [blame]290 </ul>
Andrew Trick5aab6382011-11-06 17:59:24 +0000[diff] [blame]291</div>
292
293<!--=========================================================================-->
294<h3>
Chris Lattneracce85d2008-02-10 07:46:44 +0000[diff] [blame]295<a name="optimizer">Optimizer Improvements</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]296</h3>
Chris Lattneracce85d2008-02-10 07:46:44 +0000[diff] [blame]297
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]298<div>
Chris Lattneracce85d2008-02-10 07:46:44 +0000[diff] [blame]299
Chris Lattner064caf92011-11-27 21:30:28 +0000[diff] [blame]300<p>In addition to many minor performance tweaks and bug fixes, this
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]301 release includes a few major enhancements and additions to the
302 optimizers:</p>
Chris Lattneracce85d2008-02-10 07:46:44 +0000[diff] [blame]303
304<ul>
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]305 <li>....</li>
Chris Lattner11b66112010-10-04 02:42:39 +0000[diff] [blame]306</ul>
307
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]308</div>
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]309
Chris Lattner0b832202008-06-08 02:45:07 +0000[diff] [blame]310<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]311<h3>
Chris Lattner4ba2b652010-09-30 16:31:33 +0000[diff] [blame]312<a name="mc">MC Level Improvements</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]313</h3>
Chris Lattner4ba2b652010-09-30 16:31:33 +0000[diff] [blame]314
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]315<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]316
317<p>The LLVM Machine Code (aka MC) subsystem was created to solve a number of
318 problems in the realm of assembly, disassembly, object file format handling,
319 and a number of other related areas that CPU instruction-set level tools work
Chris Lattner2f206022011-11-27 22:03:34 +0000[diff] [blame]320 in. For more information, please see
321 the <a href="http://blog.llvm.org/2010/04/intro-to-llvm-mc-project.html">Intro
322 to the LLVM MC Project Blog Post</a>.</p>
Chris Lattner7d9b6b42010-10-02 21:59:30 +0000[diff] [blame]323
Chris Lattner7d9b6b42010-10-02 21:59:30 +0000[diff] [blame]324<ul>
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]325 <li>....</li>
Chris Lattner7d9b6b42010-10-02 21:59:30 +0000[diff] [blame]326</ul>
327
NAKAMURA Takumi45c435a2011-04-05 08:24:22 +0000[diff] [blame]328</div>
Chris Lattner4ba2b652010-09-30 16:31:33 +0000[diff] [blame]329
Chris Lattner4ba2b652010-09-30 16:31:33 +0000[diff] [blame]330<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]331<h3>
Chris Lattner511433e2009-03-02 03:24:11 +0000[diff] [blame]332<a name="codegen">Target Independent Code Generator Improvements</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]333</h3>
Chris Lattner0b832202008-06-08 02:45:07 +0000[diff] [blame]334
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]335<div>
Chris Lattner0b832202008-06-08 02:45:07 +0000[diff] [blame]336
Nadav Rotem75597662011-12-20 08:02:50 +0000[diff] [blame]337<p>We have changed the way that the Type Legalizer legalizes vectors.
338 The type legalizer now attempts to promote integer elements.
339 This enabled the implementation of vector-select.
340 Additionally, we see a performance boost on workloads which use vectors of chars and shorts, since they are now promoted
341 to 32-bit types, which are better supported by the SIMD instruction set.
342 Floating point types are still widened as before.</p>
343
344
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000[diff] [blame]345<p>We have put a significant amount of work into the code generator
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]346 infrastructure, which allows us to implement more aggressive algorithms and
347 make it run faster:</p>
Chris Lattner0b832202008-06-08 02:45:07 +0000[diff] [blame]348
349<ul>
Jakob Stoklund Olesen9897c622011-12-19 16:53:40 +0000[diff] [blame]350 <li>TableGen can now synthesize register classes that are only needed to
351 represent combinations of constraints from instructions and sub-registers.
352 The synthetic register classes inherit most of their properties form their
353 closest user-defined super-class.</li>
Jakob Stoklund Olesend9e5c762012-01-05 00:26:49 +0000[diff] [blame]354 <li><code>MachineRegisterInfo</code> now allows the reserved registers to be
355 frozen when register allocation starts. Target hooks should use the
356 <code>MRI->canReserveReg(FramePtr)</code> method to avoid accidentally
357 disabling frame pointer elimination during register allocation.</li>
Jakob Stoklund Olesen7739cad2012-01-16 19:22:00 +0000[diff] [blame]358 <li>A new kind of <code>MachineOperand</code> provides a compact
359 representation of large clobber lists on call instructions. The register
360 mask operand references a bit mask of preserved registers. Everything else is
361 clobbered.</li>
Chris Lattner84977642007-09-21 03:54:09 +0000[diff] [blame]362</ul>
Chris Lattner84977642007-09-21 03:54:09 +0000[diff] [blame]363</div>
364
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]365<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]366<h3>
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]367<a name="x86">X86-32 and X86-64 Target Improvements</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]368</h3>
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]369
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]370<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]371
372<p>New features and major changes in the X86 target include:</p>
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]373
374<ul>
Nadav Rotem75597662011-12-20 08:02:50 +0000[diff] [blame]375 <li>Bug fixes and improved support for AVX1</li>
376 <li>Support for AVX2 (still incomplete at this point)</li>
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]377 <li>....</li>
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]378</ul>
379
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]380</div>
Chris Lattner84977642007-09-21 03:54:09 +0000[diff] [blame]381
382<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]383<h3>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]384<a name="ARM">ARM Target Improvements</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]385</h3>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000[diff] [blame]386
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]387<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]388
389<p>New features of the ARM target include:</p>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000[diff] [blame]390
391<ul>
Jakob Stoklund Olesenf5bb45f2011-12-16 16:07:41 +0000[diff] [blame]392 <li>The constant island pass now supports basic block and constant pool entry
393 alignments greater than 4 bytes.</li> </ul>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]394</div>
Chris Lattner7b95c382011-11-15 22:23:46 +0000[diff] [blame]395
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame]396
Chris Lattner1efe27e2011-04-06 00:45:11 +0000[diff] [blame]397<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]398<h3>
Akira Hatanaka5381cbf2011-11-15 21:33:05 +0000[diff] [blame]399<a name="MIPS">MIPS Target Improvements</a>
400</h3>
401
402<div>
403
Chris Lattner1cc489b2011-11-27 22:12:32 +0000[diff] [blame]404<p>This release has seen major new work on just about every aspect of the MIPS
405 backend. Some of the major new features include:</p>
Akira Hatanaka5381cbf2011-11-15 21:33:05 +0000[diff] [blame]406
407<ul>
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]408 <li>....</li>
Akira Hatanaka5381cbf2011-11-15 21:33:05 +0000[diff] [blame]409</ul>
410</div>
Chris Lattner7b95c382011-11-15 22:23:46 +0000[diff] [blame]411
412<!--=========================================================================-->
413<h3>
Chris Lattner1efe27e2011-04-06 00:45:11 +0000[diff] [blame]414<a name="OtherTS">Other Target Specific Improvements</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]415</h3>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000[diff] [blame]416
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]417<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]418
Chris Lattner1efe27e2011-04-06 00:45:11 +0000[diff] [blame]419<ul>
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]420 <li>....</li>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame]421
Chris Lattnerd6cc2c22011-11-27 22:36:22 +0000[diff] [blame]422
Chris Lattner1efe27e2011-04-06 00:45:11 +0000[diff] [blame]423</ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]424
Chris Lattner1efe27e2011-04-06 00:45:11 +0000[diff] [blame]425</div>
Chris Lattner77d29b12008-06-05 08:02:49 +0000[diff] [blame]426
427<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]428<h3>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]429<a name="changes">Major Changes and Removed Features</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]430</h3>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]431
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]432<div>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]433
Bill Wendling2626dba2011-08-03 22:18:20 +0000[diff] [blame]434<p>If you're already an LLVM user or developer with out-of-tree changes based on
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]435 LLVM 3.1, this section lists some "gotchas" that you may run into upgrading
Bill Wendling2626dba2011-08-03 22:18:20 +0000[diff] [blame]436 from the previous release.</p>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]437
438<ul>
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]439<li>LLVM 3.1 removes support for reading LLVM 2.9 bitcode files. Going forward,
440 we aim for all future versions of LLVM to read bitcode files and .ll files
441 produced by LLVM 3.0 and later.</li>
442 <li>....</li>
Devang Patelb34dd132008-10-14 20:03:43 +0000[diff] [blame]443</ul>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]444
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]445</div>
446
Daniel Dunbarf0233c62010-10-04 20:11:41 +0000[diff] [blame]447<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]448<h3>
Chris Lattner1efe27e2011-04-06 00:45:11 +0000[diff] [blame]449<a name="api_changes">Internal API Changes</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]450</h3>
Daniel Dunbarf0233c62010-10-04 20:11:41 +0000[diff] [blame]451
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]452<div>
Daniel Dunbarf0233c62010-10-04 20:11:41 +0000[diff] [blame]453
Chris Lattner1efe27e2011-04-06 00:45:11 +0000[diff] [blame]454<p>In addition, many APIs have changed in this release. Some of the major
Bill Wendling16005252011-08-02 06:20:17 +0000[diff] [blame]455 LLVM API changes are:</p>
Daniel Dunbarf0233c62010-10-04 20:11:41 +0000[diff] [blame]456
457<ul>
Chris Lattner21e1b7a2011-12-13 17:55:30 +0000[diff] [blame]458 <li>....</li>
Daniel Dunbarf0233c62010-10-04 20:11:41 +0000[diff] [blame]459</ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]460
Daniel Dunbarf0233c62010-10-04 20:11:41 +0000[diff] [blame]461</div>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]462
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]463</div>
464
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]465<!-- *********************************************************************** -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]466<h2>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]467 <a name="knownproblems">Known Problems</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]468</h2>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]469<!-- *********************************************************************** -->
470
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]471<div>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]472
Chris Lattner70e22012011-11-27 19:38:20 +0000[diff] [blame]473<p>LLVM is generally a production quality compiler, and is used by a broad range
474 of applications and shipping in many products. That said, not every
475 subsystem is as mature as the aggregate, particularly the more obscure
476 targets. If you run into a problem, please check the <a
477 href="http://llvm.org/bugs/">LLVM bug database</a> and submit a bug if
478 there isn't already one or ask on the <a
479 href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev
480 list</a>.</p>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame]481
Chris Lattner70e22012011-11-27 19:38:20 +0000[diff] [blame]482 <p>Known problem areas include:</p>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame]483
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]484<ul>
Chris Lattner70e22012011-11-27 19:38:20 +0000[diff] [blame]485 <li>The Alpha, Blackfin, CellSPU, MSP430, PTX, SystemZ and
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]486 XCore backends are experimental, and the Alpha, Blackfin and SystemZ
487 targets have already been removed from mainline.</li>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]488
Chris Lattner70e22012011-11-27 19:38:20 +0000[diff] [blame]489 <li>The integrated assembler, disassembler, and JIT is not supported by
490 several targets. If an integrated assembler is not supported, then a
491 system assembler is required. For more details, see the <a
492 href="CodeGenerator.html#targetfeatures">Target Features Matrix</a>.
493 </li>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame]494
Chris Lattner70e22012011-11-27 19:38:20 +0000[diff] [blame]495 <li>The C backend has numerous problems and is not being actively maintained.
496 Depending on it for anything serious is not advised.</li>
Chris Lattner26299222006-11-18 07:51:14 +0000[diff] [blame]497</ul>
498
499</div>
John Criswellc0c186d2005-11-08 21:11:33 +0000[diff] [blame]500
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]501<!-- *********************************************************************** -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]502<h2>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]503 <a name="additionalinfo">Additional Information</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]504</h2>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]505<!-- *********************************************************************** -->
506
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]507<div>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]508
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]509<p>A wide variety of additional information is available on
510 the <a href="http://llvm.org/">LLVM web page</a>, in particular in
511 the <a href="http://llvm.org/docs/">documentation</a> section. The web page
512 also contains versions of the API documentation which is up-to-date with the
513 Subversion version of the source code. You can access versions of these
514 documents specific to this release by going into the "<tt>llvm/doc/</tt>"
515 directory in the LLVM tree.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]516
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]517<p>If you have any questions or comments about LLVM, please feel free to contact
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]518 us via the <a href="http://llvm.org/docs/#maillist"> mailing lists</a>.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]519
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]520</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]521
522<!-- *********************************************************************** -->
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]523
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]524<hr>
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]525<address>
Misha Brukman38847d52003-12-21 22:53:21 +0000[diff] [blame]526 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman44408702008-12-11 17:34:48 +0000[diff] [blame]527 src="http://jigsaw.w3.org/css-validator/images/vcss-blue" alt="Valid CSS"></a>
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]528 <a href="http://validator.w3.org/check/referer"><img
Misha Brukman44408702008-12-11 17:34:48 +0000[diff] [blame]529 src="http://www.w3.org/Icons/valid-html401-blue" alt="Valid HTML 4.01"></a>
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]530
Chris Lattnerb4b0ce72007-05-18 00:44:29 +0000[diff] [blame]531 <a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]532 Last modified: $Date$
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]533</address>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]534
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]535</body>
536</html>