Gitiles
Code Review Sign In
gerrit-public.fairphone.software / fp2-dev / platform / external / llvm / 60f790c329b2f0fa9e83acfadd8858e6b4eef071 / . / docs / ReleaseNotes.html
blob: 4bd5cab7ad3c41054fb23335e0abb4a78ea89c63 [file] [log] [blame]
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">
Chad Rosiere6291d02011-05-27 22:50:46 +0000[diff] [blame]7 <title>LLVM 3.0 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
Chad Rosiere6291d02011-05-27 22:50:46 +0000[diff] [blame]11<h1>LLVM 3.0 Release Notes</h1>
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"
Gabor Greifee2187a2010-04-22 10:21:43 +0000[diff] [blame]14 width="136" height="136" alt="LLVM Dragon Logo">
Chris Lattner0e464a92010-03-17 04:02:39 +0000[diff] [blame]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>
Chad Rosiere6291d02011-05-27 22:50:46 +0000[diff] [blame]19 <li><a href="#externalproj">External Projects Using LLVM 3.0</a></li>
20 <li><a href="#whatsnew">What's New in LLVM 3.0?</a></li>
Chris Lattner4b538b92004-04-30 22:17:12 +0000[diff] [blame]21 <li><a href="GettingStarted.html">Installation Instructions</a></li>
Dan Gohman44aa9212008-10-14 16:23:02 +0000[diff] [blame]22 <li><a href="#knownproblems">Known Problems</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]23 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]24</ol>
25
Chris Lattner7911ce22004-05-23 21:07:27 +0000[diff] [blame]26<div class="doc_author">
NAKAMURA Takumib9a33632011-04-09 02:13:37 +0000[diff] [blame]27 <p>Written by the <a href="http://llvm.org/">LLVM Team</a></p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]28</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]29
Chris Lattner49123fd2011-04-06 06:29:50 +0000[diff] [blame]30<!--
Chad Rosiere6291d02011-05-27 22:50:46 +0000[diff] [blame]31<h1 style="color:red">These are in-progress notes for the upcoming LLVM 3.0
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]32release.<br>
33You may prefer the
Chad Rosiere6291d02011-05-27 22:50:46 +0000[diff] [blame]34<a href="http://llvm.org/releases/2.9/docs/ReleaseNotes.html">LLVM 2.9
Dan Gohmanb44f6c62010-05-03 23:51:05 +0000[diff] [blame]35Release Notes</a>.</h1>
Chris Lattner49123fd2011-04-06 06:29:50 +0000[diff] [blame]36 -->
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
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]47 Infrastructure, release 3.0. 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
75<p>The LLVM 3.0 distribution currently consists of code from the core LLVM
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
Chad Rosiere6291d02011-05-27 22:50:46 +0000[diff] [blame]97<p>In the LLVM 3.0 time-frame, the Clang team has made many improvements:</p>
Douglas Gregorba087df2011-10-15 00:48:01 +0000[diff] [blame]98
99<ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]100 <li>Greatly improved support for building C++ applications, with greater
101 stability and better diagnostics.</li>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]102
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]103 <li><a href="http://clang.llvm.org/cxx_status.html">Improved support</a> for
104 the <a href="http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=50372">C++
Chris Lattner1ab8ce92011-11-27 18:47:37 +0000[diff] [blame]105 2011</a> standard (aka "C++'0x"), including implementations of non-static data member
106 initializers, alias templates, delegating constructors, range-based
107 for loops, and implicitly-generated move constructors and move assignment
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]108 operators, among others.</li>
Douglas Gregorba087df2011-10-15 00:48:01 +0000[diff] [blame]109
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]110 <li>Implemented support for some features of the upcoming C1x standard,
111 including static assertions and generic selections.</li>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]112
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]113 <li>Better detection of include and linking paths for system headers and
114 libraries, especially for Linux distributions.</li>
Douglas Gregorba087df2011-10-15 00:48:01 +0000[diff] [blame]115
David Chisnall553284e2011-11-26 10:56:17 +0000[diff] [blame]116 <li>Several improvements to Objective-C support, including:
117
118 <ul>
119 <li><a href="http://clang.llvm.org/docs/AutomaticReferenceCounting.html">
120 Automatic Reference Counting</a> (ARC) and an improved memory model
121 cleanly separating object and C memory.</li>
122
Chris Lattner1ab8ce92011-11-27 18:47:37 +0000[diff] [blame]123 <li>A migration tool for moving manual retain/release code to ARC</li>
David Chisnall553284e2011-11-26 10:56:17 +0000[diff] [blame]124
125 <li>Better support for data hiding, allowing instance variables to be
126 declared in implementation contexts or class extensions</li>
Chris Lattner1ab8ce92011-11-27 18:47:37 +0000[diff] [blame]127 <li>Weak linking support for Objective-C classes</li>
David Chisnall553284e2011-11-26 10:56:17 +0000[diff] [blame]128 <li>Improved static type checking by inferring the return type of methods
129 such as +alloc and -init.</li>
130 </ul>
131
Chris Lattner1ab8ce92011-11-27 18:47:37 +0000[diff] [blame]132 Some new Objective-C features require either the Mac OS X 10.7 / iOS 5
133 Objective-C runtime, or version 1.6 or later of the GNUstep Objective-C
134 runtime version.</li>
Douglas Gregorba087df2011-10-15 00:48:01 +0000[diff] [blame]135
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]136 <li>Implemented a number of optimizations in <tt>libclang</tt>, the Clang C
137 interface, to improve the performance of code completion and the mapping
138 from source locations to abstract syntax tree nodes.</li>
Douglas Gregorba087df2011-10-15 00:48:01 +0000[diff] [blame]139</ul>
140
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]141
Duncan Sandsf3ba7af2011-04-06 08:07:40 +0000[diff] [blame]142<p>If Clang rejects your code but another compiler accepts it, please take a
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]143 look at the <a href="http://clang.llvm.org/compatibility.html">language
144 compatibility</a> guide to make sure this is not intentional or a known
145 issue.</p>
Bill Wendling741748a2008-10-27 09:27:33 +0000[diff] [blame]146
Chris Lattnerfb97b2d2008-10-13 18:11:54 +0000[diff] [blame]147</div>
148
149<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]150<h3>
Duncan Sands528a5102011-04-04 11:09:08 +0000[diff] [blame]151<a name="dragonegg">DragonEgg: GCC front-ends, LLVM back-end</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]152</h3>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]153
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]154<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]155<p><a href="http://dragonegg.llvm.org/">DragonEgg</a> is a
156 <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]157 optimizers and code generators with LLVM's. It works with gcc-4.5 or gcc-4.6,
158 targets the x86-32 and x86-64 processor families, and has been successfully
159 used on the Darwin, FreeBSD, KFreeBSD, Linux and OpenBSD platforms. It fully
160 supports Ada, C, C++ and Fortran. It has partial support for Go, Java, Obj-C
161 and Obj-C++.</p>
Duncan Sands749fd832010-04-02 09:23:15 +0000[diff] [blame]162
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]163<p>The 3.0 release has the following notable changes:</p>
164
Chris Lattner1ab8ce92011-11-27 18:47:37 +0000[diff] [blame]165 <ul>
Duncan Sands77352c92011-11-10 18:44:29 +0000[diff] [blame]166 <li>GCC version 4.6 is now fully supported.</li>
167
168 <li>Patching and building GCC is no longer required: the plugin should work
169 with your system GCC (version 4.5 or 4.6; on Debian/Ubuntu systems the
170 gcc-4.5-plugin-dev or gcc-4.6-plugin-dev package is also needed).</li>
171
172 <li>The <tt>-fplugin-arg-dragonegg-enable-gcc-optzns</tt> option, which runs
173 GCC's optimizers as well as LLVM's, now works much better. This is the
Chris Lattner1ab8ce92011-11-27 18:47:37 +0000[diff] [blame]174 option to use if you want ultimate performance! It is still experimental
175 though: it may cause the plugin to crash.</li>
Duncan Sands77352c92011-11-10 18:44:29 +0000[diff] [blame]176
177 <li>The type and constant conversion logic has been almost entirely rewritten,
178 fixing a multitude of obscure bugs.</li>
179
Duncan Sands4b1da2b2010-09-30 17:37:34 +0000[diff] [blame]180</ul>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]181
182</div>
183
Chris Lattner75547712010-10-03 23:49:06 +0000[diff] [blame]184<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]185<h3>
Chris Lattner75547712010-10-03 23:49:06 +0000[diff] [blame]186<a name="compiler-rt">compiler-rt: Compiler Runtime Library</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]187</h3>
Chris Lattner75547712010-10-03 23:49:06 +0000[diff] [blame]188
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]189<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]190
191<p>The new LLVM <a href="http://compiler-rt.llvm.org/">compiler-rt project</a>
192 is a simple library that provides an implementation of the low-level
193 target-specific hooks required by code generation and other runtime
194 components. For example, when compiling for a 32-bit target, converting a
195 double to a 64-bit unsigned integer is compiled into a runtime call to the
196 "__fixunsdfdi" function. The compiler-rt library provides highly optimized
197 implementations of this and other low-level routines (some are 3x faster than
198 the equivalent libgcc routines).</p>
Chris Lattner75547712010-10-03 23:49:06 +0000[diff] [blame]199
Chris Lattner1ab8ce92011-11-27 18:47:37 +0000[diff] [blame]200<p>In the LLVM 3.0 timeframe, the target specific ARM code has converted to
201 "unified" assembly syntax, and several new functions have been added to the
202 library.</p>
Chris Lattner75547712010-10-03 23:49:06 +0000[diff] [blame]203
204</div>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]205
206<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]207<h3>
Chris Lattnere07043c2010-09-29 05:30:03 +0000[diff] [blame]208<a name="lldb">LLDB: Low Level Debugger</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]209</h3>
Chris Lattnere07043c2010-09-29 05:30:03 +0000[diff] [blame]210
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]211<div>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]212
Chris Lattner9e896712011-11-27 18:53:41 +0000[diff] [blame]213<p>LLDB is a ground-up implementation of a command line debugger, as well as a
214 debugger API that can be used from other applications. LLDB makes use of the
215 Clang parser to provide high-fidelity expression parsing (particularly for
216 C++) and uses the LLVM JIT for target support.</p>
Chris Lattnere07043c2010-09-29 05:30:03 +0000[diff] [blame]217
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]218<p>LLDB has advanced by leaps and bounds in the 3.0 timeframe. It is
219 dramatically more stable and useful, and includes both a
220 new <a href="http://lldb.llvm.org/tutorial.html">tutorial</a> and
221 a <a href="http://lldb.llvm.org/lldb-gdb.html">side-by-side comparison with
222 GDB</a>.</p>
Chris Lattnere07043c2010-09-29 05:30:03 +0000[diff] [blame]223
224</div>
225
226<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]227<h3>
Chris Lattnere07043c2010-09-29 05:30:03 +0000[diff] [blame]228<a name="libc++">libc++: C++ Standard Library</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]229</h3>
Chris Lattnere07043c2010-09-29 05:30:03 +0000[diff] [blame]230
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]231<div>
Chris Lattnere07043c2010-09-29 05:30:03 +0000[diff] [blame]232
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]233<p>Like compiler_rt, libc++ is now <a href="DeveloperPolicy.html#license">dual
234 licensed</a> under the MIT and UIUC license, allowing it to be used more
235 permissively.</p>
Chris Lattnere07043c2010-09-29 05:30:03 +0000[diff] [blame]236
David Chisnall553284e2011-11-26 10:56:17 +0000[diff] [blame]237<p>Libc++ has been ported to FreeBSD and imported into the base system. It is
238 planned to be the default STL implementation for FreeBSD 10.</p>
239
Chris Lattnere07043c2010-09-29 05:30:03 +0000[diff] [blame]240</div>
241
Chris Lattner3d6a80a2011-04-07 03:08:22 +0000[diff] [blame]242<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]243<h3>
Chris Lattner3d6a80a2011-04-07 03:08:22 +0000[diff] [blame]244<a name="vmkit">VMKit</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]245</h3>
Chris Lattner3d6a80a2011-04-07 03:08:22 +0000[diff] [blame]246
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]247<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]248
Nicolas Geoffray54d5df92011-11-10 23:37:56 +0000[diff] [blame]249 <p>The <a href="http://vmkit.llvm.org/">VMKit project</a> is an
250 implementation of a Java Virtual Machine (Java VM or JVM) that uses LLVM for
251 static and just-in-time compilation.
252
253 <p>In the LLVM 3.0 time-frame, VMKit has had significant improvements on both
254 runtime and startup performance:</p>
255
256 <ul>
257 <li>Precompilation: by compiling ahead of time a small subset of Java's core
258 library, the startup performance have been highly optimized to the point that
259 running a 'Hello World' program takes less than 30 milliseconds.</li>
260
261 <li>Customization: by customizing virtual methods for individual classes,
262 the VM can statically determine the target of a virtual call, and decide to
263 inline it.</li>
264
265 <li>Inlining: the VM does more inlining than it did before, by allowing more
266 bytecode instructions to be inlined, and thanks to customization. It also
267 inlines GC barriers, and object allocations.</li>
268
269 <li>New exception model: the generated code for a method that does not do
270 any try/catch is not penalized anymore by the eventuality of calling a
271 method that throws an exception. Instead, the method that throws the
272 exception jumps directly to the method that could catch it.</li>
273 </ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]274
Chris Lattner3d6a80a2011-04-07 03:08:22 +0000[diff] [blame]275</div>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]276
Chris Lattner9e896712011-11-27 18:53:41 +0000[diff] [blame]277
278<!--=========================================================================-->
279<h3>
280<a name="LLBrowse">LLBrowse: IR Browser</a>
281</h3>
282
283<div>
284
285<p><a href="http://llvm.org/svn/llvm-project/llbrowse/trunk/doc/LLBrowse.html">
286 LLBrowse</a> is an interactive viewer for LLVM modules. It can load any LLVM
287 module and displays its contents as an expandable tree view, facilitating an
288 easy way to inspect types, functions, global variables, or metadata nodes. It
289 is fully cross-platform, being based on the popular wxWidgets GUI
290 toolkit.</p>
291
292</div>
293
294
Daniel Dunbar97b01a82010-10-04 17:39:47 +0000[diff] [blame]295<!--=========================================================================-->
Chris Lattner7a8e6c52011-04-05 18:38:45 +0000[diff] [blame]296<!--
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]297<h3>
Daniel Dunbar97b01a82010-10-04 17:39:47 +0000[diff] [blame]298<a name="klee">KLEE: A Symbolic Execution Virtual Machine</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]299</h3>
Daniel Dunbar97b01a82010-10-04 17:39:47 +0000[diff] [blame]300
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]301<div>
Daniel Dunbar97b01a82010-10-04 17:39:47 +0000[diff] [blame]302<p>
303<a href="http://klee.llvm.org/">KLEE</a> is a symbolic execution framework for
304programs in LLVM bitcode form. KLEE tries to symbolically evaluate "all" paths
305through the application and records state transitions that lead to fault
306states. This allows it to construct testcases that lead to faults and can even
307be used to verify some algorithms.
308</p>
309
Chris Lattnerbe2e1b52011-03-10 07:43:44 +0000[diff] [blame]310<p>UPDATE!</p>
Chris Lattner7a8e6c52011-04-05 18:38:45 +0000[diff] [blame]311</div>-->
Daniel Dunbar97b01a82010-10-04 17:39:47 +0000[diff] [blame]312
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]313</div>
Daniel Dunbar97b01a82010-10-04 17:39:47 +0000[diff] [blame]314
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000[diff] [blame]315<!-- *********************************************************************** -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]316<h2>
Chad Rosiere6291d02011-05-27 22:50:46 +0000[diff] [blame]317 <a name="externalproj">External Open Source Projects Using LLVM 3.0</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]318</h2>
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000[diff] [blame]319<!-- *********************************************************************** -->
320
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]321<div>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]322
323<p>An exciting aspect of LLVM is that it is used as an enabling technology for
324 a lot of other language and tools projects. This section lists some of the
Chad Rosiere6291d02011-05-27 22:50:46 +0000[diff] [blame]325 projects that have already been updated to work with LLVM 3.0.</p>
Chris Lattner75547712010-10-03 23:49:06 +0000[diff] [blame]326
Chris Lattner3bfe57e2011-04-06 01:13:49 +0000[diff] [blame]327<!--=========================================================================-->
Bill Wendling7be6bc52011-10-26 00:17:54 +0000[diff] [blame]328<h3>AddressSanitizer</h3>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]329
Bill Wendling7be6bc52011-10-26 00:17:54 +0000[diff] [blame]330<div>
331
332<p><a href="http://code.google.com/p/address-sanitizer/">AddressSanitizer</a>
333 uses compiler instrumentation and a specialized malloc library to find C/C++
334 bugs such as use-after-free and out-of-bound accesses to heap, stack, and
335 globals. The key feature of the tool is speed: the average slowdown
336 introduced by AddressSanitizer is less than 2x.</p>
337
338</div>
339
340<!--=========================================================================-->
Bill Wendling29817ea2011-10-26 00:14:36 +0000[diff] [blame]341<h3>ClamAV</h3>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]342
Bill Wendling29817ea2011-10-26 00:14:36 +0000[diff] [blame]343<div>
Bill Wendlingf2a78332011-10-25 01:01:42 +0000[diff] [blame]344
Bill Wendling29817ea2011-10-26 00:14:36 +0000[diff] [blame]345<p><a href="http://www.clamav.net">Clam AntiVirus</a> is an open source (GPL)
346 anti-virus toolkit for UNIX, designed especially for e-mail scanning on mail
347 gateways.</p>
348
349<p>Since version 0.96 it
350 has <a href="http://vrt-sourcefire.blogspot.com/2010/09/introduction-to-clamavs-low-level.html">bytecode
Chris Lattner4f0fe432011-11-27 19:26:30 +0000[diff] [blame]351 signatures</a> that allow writing detections for complex malware.
352 It uses LLVM's JIT to speed up the execution of bytecode on X86, X86-64,
Bill Wendling29817ea2011-10-26 00:14:36 +0000[diff] [blame]353 PPC32/64, falling back to its own interpreter otherwise. The git version was
354 updated to work with LLVM 3.0.</p>
355
356</div>
357
358<!--=========================================================================-->
Tobias Grosserae5a6fd2011-11-14 09:09:26 +0000[diff] [blame]359<h3>clang_complete for VIM</h3>
360
361<div>
362
363<p><a href="https://github.com/Rip-Rip/clang_complete">clang_complete</a> is a
364 VIM plugin, that provides accurate C/C++ autocompletion using the clang front
365 end. The development version of clang complete, can directly use libclang
366 which can maintain a cache to speed up auto completion.</p>
367
368</div>
369
370<!--=========================================================================-->
Bill Wendling65d1f412011-10-26 18:23:06 +0000[diff] [blame]371<h3>clReflect</h3>
372
373<div>
374
375<p><a href="https://bitbucket.org/dwilliamson/clreflect">clReflect</a> is a C++
376 parser that uses clang/LLVM to derive a light-weight reflection database
377 suitable for use in game development. It comes with a very simple runtime
378 library for loading and querying the database, requiring no external
379 dependencies (including CRT), and an additional utility library for object
380 management and serialisation.</p>
381
382</div>
383
384<!--=========================================================================-->
Bill Wendling63507d12011-10-29 01:10:01 +0000[diff] [blame]385<h3>Cling C++ Interpreter</h3>
386
387<div>
388
389<p><a href="http://cern.ch/cling">Cling</a> is an interactive compiler interface
Chris Lattner4f0fe432011-11-27 19:26:30 +0000[diff] [blame]390 (aka C++ interpreter). It supports C++ and C, and uses LLVM's JIT and the
391 Clang parser. It has a prompt interface, runs source files, calls into shared
Bill Wendling63507d12011-10-29 01:10:01 +0000[diff] [blame]392 libraries, prints the value of expressions, even does runtime lookup of
393 identifiers (dynamic scopes). And it just behaves like one would expect from
394 an interpreter.</p>
395
396</div>
397
398<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]399<h3>Crack Programming Language</h3>
Chris Lattner3bfe57e2011-04-06 01:13:49 +0000[diff] [blame]400
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]401<div>
Bill Wendling55d6e672011-11-03 20:10:01 +0000[diff] [blame]402
403<p><a href="http://code.google.com/p/crack-language/">Crack</a> aims to provide
404 the ease of development of a scripting language with the performance of a
405 compiled language. The language derives concepts from C++, Java and Python,
406 incorporating object-oriented programming, operator overloading and strong
407 typing.</p>
408
Chris Lattner3bfe57e2011-04-06 01:13:49 +0000[diff] [blame]409</div>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]410
Chris Lattner3bfe57e2011-04-06 01:13:49 +0000[diff] [blame]411<!--=========================================================================-->
Bill Wendlingb99486f2011-11-08 05:22:54 +0000[diff] [blame]412<h3>Eero</h3>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]413
Bill Wendlingb99486f2011-11-08 05:22:54 +0000[diff] [blame]414<div>
415
416<p><a href="http://eerolanguage.org/">Eero</a> is a fully
417 header-and-binary-compatible dialect of Objective-C 2.0, implemented with a
418 patched version of the Clang/LLVM compiler. It features a streamlined syntax,
419 Python-like indentation, and new operators, for improved readability and
420 reduced code clutter. It also has new features such as limited forms of
421 operator overloading and namespaces, and strict (type-and-operator-safe)
422 enumerations. It is inspired by languages such as Smalltalk, Python, and
423 Ruby.</p>
424
425</div>
426
427<!--=========================================================================-->
Chris Lattneradb417a2011-11-25 20:28:16 +0000[diff] [blame]428<h3>FAUST Real-Time Audio Signal Processing Language</h3>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]429
Chris Lattneradb417a2011-11-25 20:28:16 +0000[diff] [blame]430<div>
431
432<p><a href="http://faust.grame.fr/">FAUST</a> is a compiled language for
433 real-time audio signal processing. The name FAUST stands for Functional
434 AUdio STream. Its programming model combines two approaches: functional
435 programming and block diagram composition. In addition with the C, C++, Java
436 output formats, the Faust compiler can now generate LLVM bitcode, and works
437 with LLVM 2.7-3.0.
438 </p>
439
440</div>
441
442<!--=========================================================================-->
Bill Wendlingf9778192011-10-26 00:09:55 +0000[diff] [blame]443<h3>Glasgow Haskell Compiler (GHC)</h3>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]444
Bill Wendlingf9778192011-10-26 00:09:55 +0000[diff] [blame]445<div>
446
447<p>GHC is an open source, state-of-the-art programming suite for Haskell, a
448 standard lazy functional programming language. It includes an optimizing
449 static compiler generating good code for a variety of platforms, together
450 with an interactive system for convenient, quick development.</p>
451
452<p>GHC 7.0 and onwards include an LLVM code generator, supporting LLVM 2.8 and
453 later. Since LLVM 2.9, GHC now includes experimental support for the ARM
454 platform with LLVM 3.0.</p>
455
456</div>
457
458<!--=========================================================================-->
Bill Wendlingf62333d2011-10-25 20:35:31 +0000[diff] [blame]459<h3>gwXscript</h3>
460
461<div>
462
463<p><a href="http://botwars.tk/gwscript/">gwXscript</a> is an object oriented,
Bill Wendling7c38de22011-10-26 04:24:15 +0000[diff] [blame]464 aspect oriented programming language which can create both executables (ELF,
Bill Wendlingf62333d2011-10-25 20:35:31 +0000[diff] [blame]465 EXE) and shared libraries (DLL, SO, DYNLIB). The compiler is implemented in
466 its own language and translates scripts into LLVM-IR which can be optimized
467 and translated into native code by the LLVM framework. Source code in
468 gwScript contains definitions that expand the namespaces. So you can build
469 your project and simply 'plug out' features by removing a file. The remaining
470 project does not leave scars since you directly separate concerns by the
471 'template' feature of gwX. It is also possible to add new features to a
472 project by just adding files and without editing the original project. This
473 language is used for example to create games or content management systems
474 that should be extendable.</p>
475
476<p>gwXscript is strongly typed and offers comfort with its native types string,
477 hash and array. You can easily write new libraries in gwXscript or native
478 code. gwXscript is type safe and users should not be able to crash your
479 program or execute malicious code except code that is eating CPU time.</p>
480
481</div>
482
483<!--=========================================================================-->
Bill Wendling50cacc82011-10-26 22:55:18 +0000[diff] [blame]484<h3>include-what-you-use</h3>
485
486<div>
487
488<p><a href="http://code.google.com/p/include-what-you-use">include-what-you-use</a>
489 is a tool to ensure that a file directly <code>#include</code>s
490 all <code>.h</code> files that provide a symbol that the file uses. It also
491 removes superfluous <code>#include</code>s from source files.</p>
492
493</div>
494
495<!--=========================================================================-->
Bill Wendling32dc4d92011-11-07 22:05:17 +0000[diff] [blame]496<h3>ispc: The Intel SPMD Program Compiler</h3>
497
498<div>
499
500<p><a href="http://ispc.github.com">ispc</a> is a compiler for "single program,
501 multiple data" (SPMD) programs. It compiles a C-based SPMD programming
502 language to run on the SIMD units of CPUs; it often delivers 5-6x speedups on
503 a single core of a CPU with an 8-wide SIMD unit compared to serial code,
504 while still providing a clean and easy-to-understand programming model. For
505 an introduction to the language and its performance,
Chris Lattnerc343e312011-11-10 20:15:40 +0000[diff] [blame]506 see <a href="http://ispc.github.com/example.html">the walkthrough</a> of a short
Bill Wendling32dc4d92011-11-07 22:05:17 +0000[diff] [blame]507 example program. ispc is licensed under the BSD license.</p>
508
509</div>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]510
Chris Lattnercc089772011-11-25 20:36:17 +0000[diff] [blame]511<!--=========================================================================-->
512<h3>The Julia Programming Language</h3>
513
514<div>
515
516<p><a href="http://github.com/JuliaLang/julia">Julia</a> is a high-level,
517 high-performance dynamic language for technical
518 computing. It provides a sophisticated compiler, distributed parallel
519 execution, numerical accuracy, and an extensive mathematical function
520 library. The compiler uses type inference to generate fast code
521 without any type declarations, and uses LLVM's optimization passes and
522 JIT compiler. The language is designed around multiple dispatch,
523 giving programs a large degree of flexibility. It is ready for use on many
524 kinds of problems.</p>
525</div>
Bill Wendling32dc4d92011-11-07 22:05:17 +0000[diff] [blame]526
527<!--=========================================================================-->
Bill Wendling57fd8762011-10-26 18:20:54 +0000[diff] [blame]528<h3>LanguageKit and Pragmatic Smalltalk</h3>
529
530<div>
531
532<p><a href="http://etoileos.com/etoile/features/languagekit/">LanguageKit</a> is
533 a framework for implementing dynamic languages sharing an object model with
534 Objective-C. It provides static and JIT compilation using LLVM along with
535 its own interpreter. Pragmatic Smalltalk is a dialect of Smalltalk, built on
536 top of LanguageKit, that interfaces directly with Objective-C, sharing the
537 same object representation and message sending behaviour. These projects are
Benjamin Kramer7c5025b2011-11-25 21:26:00 +0000[diff] [blame]538 developed as part of the &Eacute;toil&eacute; desktop environment.</p>
Bill Wendling57fd8762011-10-26 18:20:54 +0000[diff] [blame]539
540</div>
541
542<!--=========================================================================-->
Bill Wendling03250532011-11-01 04:08:23 +0000[diff] [blame]543<h3>LuaAV</h3>
544
545<div>
546
547<p><a href="http://lua-av.mat.ucsb.edu/blog/">LuaAV</a> is a real-time
548 audiovisual scripting environment based around the Lua language and a
549 collection of libraries for sound, graphics, and other media protocols. LuaAV
550 uses LLVM and Clang to JIT compile efficient user-defined audio synthesis
551 routines specified in a declarative syntax.</p>
552
553</div>
554
555<!--=========================================================================-->
Bill Wendlingd4821b82011-10-26 00:16:17 +0000[diff] [blame]556<h3>Mono</h3>
557
558<div>
559
560<p>An open source, cross-platform implementation of C# and the CLR that is
561 binary compatible with Microsoft.NET. Has an optional, dynamically-loaded
562 LLVM code generation backend in Mini, the JIT compiler.</p>
563
Chris Lattner4f0fe432011-11-27 19:26:30 +0000[diff] [blame]564<p>Note that we use a Git mirror of LLVM <a
565 href="https://github.com/mono/llvm">with some patches</a>.</p>
Bill Wendlingd4821b82011-10-26 00:16:17 +0000[diff] [blame]566
567</div>
568
569<!--=========================================================================-->
Tobias Grosser093cb7e2011-11-14 09:09:23 +0000[diff] [blame]570<h3>Polly</h3>
571
572<div>
573
574<p><a href="http://polly.grosser.es">Polly</a> is an advanced data-locality
575 optimizer and automatic parallelizer. It uses an advanced, mathematical
576 model to calculate detailed data dependency information which it uses to
577 optimize the loop structure of a program. Polly can speed up sequential code
578 by improving memory locality and consequently the cache use. Furthermore,
579 Polly is able to expose different kind of parallelism which it exploits by
580 introducing (basic) OpenMP and SIMD code. A mid-term goal of Polly is to
581 automatically create optimized GPU code.</p>
582
583</div>
584
585<!--=========================================================================-->
Bill Wendlingba226272011-10-25 20:37:45 +0000[diff] [blame]586<h3>Portable OpenCL (pocl)</h3>
587
588<div>
589
590<p>Portable OpenCL is an open source implementation of the OpenCL standard which
591 can be easily adapted for new targets. One of the goals of the project is
592 improving performance portability of OpenCL programs, avoiding the need for
593 target-dependent manual optimizations. A "native" target is included, which
594 allows running OpenCL kernels on the host (CPU).</p>
595
596</div>
597
598<!--=========================================================================-->
Bill Wendling0bad98c2011-10-25 20:39:06 +0000[diff] [blame]599<h3>Pure</h3>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]600
Bill Wendling0bad98c2011-10-25 20:39:06 +0000[diff] [blame]601<div>
602<p><a href="http://pure-lang.googlecode.com/">Pure</a> is an
603 algebraic/functional programming language based on term rewriting. Programs
604 are collections of equations which are used to evaluate expressions in a
605 symbolic fashion. The interpreter uses LLVM as a backend to JIT-compile Pure
606 programs to fast native code. Pure offers dynamic typing, eager and lazy
607 evaluation, lexical closures, a hygienic macro system (also based on term
608 rewriting), built-in list and matrix support (including list and matrix
609 comprehensions) and an easy-to-use interface to C and other programming
610 languages (including the ability to load LLVM bitcode modules, and inline C,
611 C++, Fortran and Faust code in Pure programs if the corresponding LLVM-enabled
612 compilers are installed).</p>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]613
Bill Wendling0bad98c2011-10-25 20:39:06 +0000[diff] [blame]614<p>Pure version 0.48 has been tested and is known to work with LLVM 3.0
615 (and continues to work with older LLVM releases &gt;= 2.5).</p>
616
617</div>
618
619<!--=========================================================================-->
Bill Wendling537d85b2011-10-26 00:12:04 +0000[diff] [blame]620<h3>Renderscript</h3>
621
622<div>
623
624<p><a href="http://developer.android.com/guide/topics/renderscript/index.html">Renderscript</a>
625 is Android's advanced 3D graphics rendering and compute API. It provides a
626 portable C99-based language with extensions to facilitate common use cases
627 for enhancing graphics and thread level parallelism. The Renderscript
628 compiler frontend is based on Clang/LLVM. It emits a portable bitcode format
629 for the actual compiled script code, as well as reflects a Java interface for
630 developers to control the execution of the compiled bitcode. Executable
631 machine code is then generated from this bitcode by an LLVM backend on the
632 device. Renderscript is thus able to provide a mechanism by which Android
633 developers can improve performance of their applications while retaining
634 portability.</p>
635
636</div>
637
638<!--=========================================================================-->
Bill Wendling7d5b6212011-10-25 20:40:26 +0000[diff] [blame]639<h3>SAFECode</h3>
640
641<div>
642
643<p><a href="http://safecode.cs.illinois.edu">SAFECode</a> is a memory safe C/C++
644 compiler built using LLVM. It takes standard, unannotated C/C++ code,
645 analyzes the code to ensure that memory accesses and array indexing
646 operations are safe, and instruments the code with run-time checks when
647 safety cannot be proven statically. SAFECode can be used as a debugging aid
648 (like Valgrind) to find and repair memory safety bugs. It can also be used
649 to protect code from security attacks at run-time.</p>
650
651</div>
652
653<!--=========================================================================-->
Bill Wendling02b77b72011-10-26 07:38:19 +0000[diff] [blame]654<h3>The Stupid D Compiler (SDC)</h3>
655
656<div>
657
658<p><a href="https://github.com/bhelyer/SDC">The Stupid D Compiler</a> is a
659 project seeking to write a self-hosting compiler for the D programming
660 language without using the frontend of the reference compiler (DMD).</p>
661
662</div>
663
664<!--=========================================================================-->
Bill Wendling2d7b4af2011-10-25 20:24:32 +0000[diff] [blame]665<h3>TTA-based Co-design Environment (TCE)</h3>
666
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]667<div>
Bill Wendling2d7b4af2011-10-25 20:24:32 +0000[diff] [blame]668
Chris Lattner3bfe57e2011-04-06 01:13:49 +0000[diff] [blame]669<p>TCE is a toolset for designing application-specific processors (ASP) based on
Bill Wendling2d7b4af2011-10-25 20:24:32 +0000[diff] [blame]670 the Transport triggered architecture (TTA). The toolset provides a complete
671 co-design flow from C/C++ programs down to synthesizable VHDL and parallel
672 program binaries. Processor customization points include the register files,
673 function units, supported operations, and the interconnection network.</p>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]674
Chris Lattner3bfe57e2011-04-06 01:13:49 +0000[diff] [blame]675<p>TCE uses Clang and LLVM for C/C++ language support, target independent
Bill Wendling2d7b4af2011-10-25 20:24:32 +0000[diff] [blame]676 optimizations and also for parts of code generation. It generates new
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]677 LLVM-based code generators "on the fly" for the designed TTA processors and
678 loads them in to the compiler backend as runtime libraries to avoid
Bill Wendling2d7b4af2011-10-25 20:24:32 +0000[diff] [blame]679 per-target recompilation of larger parts of the compiler chain.</p>
Chris Lattner3bfe57e2011-04-06 01:13:49 +0000[diff] [blame]680
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]681</div>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]682
Chris Lattner3bfe57e2011-04-06 01:13:49 +0000[diff] [blame]683<!--=========================================================================-->
Bill Wendling628c2662011-10-25 20:27:37 +0000[diff] [blame]684<h3>Tart Programming Language</h3>
685
686<div>
687
688<p><a href="http://code.google.com/p/tart/">Tart</a> is a general-purpose,
689 strongly typed programming language designed for application
690 developers. Strongly inspired by Python and C#, Tart focuses on practical
691 solutions for the professional software developer, while avoiding the clutter
692 and boilerplate of legacy languages like Java and C++. Although Tart is still
693 in development, the current implementation supports many features expected of
694 a modern programming language, such as garbage collection, powerful
695 bidirectional type inference, a greatly simplified syntax for template
696 metaprogramming, closures and function literals, reflection, operator
697 overloading, explicit mutability and immutability, and much more. Tart is
698 flexible enough to accommodate a broad range of programming styles and
699 philosophies, while maintaining a strong commitment to simplicity, minimalism
700 and elegance in design.</p>
701
702</div>
703
704<!--=========================================================================-->
Bill Wendling644ce532011-10-26 09:25:01 +0000[diff] [blame]705<h3>ThreadSanitizer</h3>
706
707<div>
708
709<p><a href="http://code.google.com/p/data-race-test/">ThreadSanitizer</a> is a
710 data race detector for (mostly) C and C++ code, available for Linux, Mac OS
711 and Windows. On different systems, we use binary instrumentation frameworks
Bill Wendlingae8538e2011-10-29 01:11:15 +0000[diff] [blame]712 (Valgrind and Pin) as frontends that generate the program events for the race
713 detection algorithm. On Linux, there's an option of using LLVM-based
714 compile-time instrumentation.</p>
Bill Wendling644ce532011-10-26 09:25:01 +0000[diff] [blame]715
716</div>
717
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]718</div>
719
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]720<!-- *********************************************************************** -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]721<h2>
Chad Rosiere6291d02011-05-27 22:50:46 +0000[diff] [blame]722 <a name="whatsnew">What's New in LLVM 3.0?</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]723</h2>
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]724<!-- *********************************************************************** -->
725
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]726<div>
Chris Lattnerf8e0b4e2008-06-08 22:59:35 +0000[diff] [blame]727
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]728<p>This release includes a huge number of bug fixes, performance tweaks and
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]729 minor improvements. Some of the major improvements and new features are
730 listed in this section.</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]731
Chris Lattner914ce462010-04-22 06:28:20 +0000[diff] [blame]732<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]733<h3>
Chris Lattner252b83d2008-02-06 18:00:06 +0000[diff] [blame]734<a name="majorfeatures">Major New Features</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]735</h3>
Chris Lattner252b83d2008-02-06 18:00:06 +0000[diff] [blame]736
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]737<div>
Chris Lattner252b83d2008-02-06 18:00:06 +0000[diff] [blame]738
Chris Lattner1ab8ce92011-11-27 18:47:37 +0000[diff] [blame]739 <!-- Features that need text if they're finished for 3.1:
740 ARM EHABI
741 combiner-aa?
742 strong phi elim
743 loop dependence analysis
744 CorrelatedValuePropagation
745 lib/Transforms/IPO/MergeFunctions.cpp => consider for 3.1.
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]746 Integrated assembler on by default for arm/thumb?
747
Chris Lattner1ab8ce92011-11-27 18:47:37 +0000[diff] [blame]748 -->
749
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]750 <!-- Near dead:
Chris Lattnerdec23b62011-11-15 22:13:27 +0000[diff] [blame]751 Analysis/RegionInfo.h + Dom Frontiers
752 SparseBitVector: used in LiveVar.
Chris Lattner5a1731d2011-11-27 08:32:32 +0000[diff] [blame]753 llvm/lib/Archive - replace with lib object?
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]754 -->
Chris Lattner6a007d12011-11-25 20:33:27 +0000[diff] [blame]755
Chris Lattner064caf92011-11-27 21:30:28 +0000[diff] [blame]756<p>LLVM 3.0 includes several major changes and big features:</p>
Bill Wendlingbc5f6dd2011-10-26 18:33:01 +0000[diff] [blame]757
Chris Lattner791f77b2008-06-05 06:25:56 +0000[diff] [blame]758<ul>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]759<li>llvm-gcc is no longer supported, and not included in the release. We
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]760 recommend switching to <a
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]761 href="http://clang.llvm.org/">Clang</a> or <a
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]762 href="http://dragonegg.llvm.org/">DragonEgg</a>.</li>
Bill Wendlingbc5f6dd2011-10-26 18:33:01 +0000[diff] [blame]763
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]764<li>The linear scan register allocator has been replaced with a new "greedy"
765 register allocator, enabling live range splitting and many other
766 optimizations that lead to better code quality. Please see its <a
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]767 href="http://blog.llvm.org/2011/09/greedy-register-allocation-in-llvm-30.html">blog post</a> or its talk at the <a
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]768 href="http://llvm.org/devmtg/2011-11/">Developer Meeting</a>
769 for more information.</li>
Chris Lattner064caf92011-11-27 21:30:28 +0000[diff] [blame]770<li>LLVM IR now includes full support for <a href="Atomics.html">atomics
771 memory operations</a> intended to support the C++'11 and C'1x memory models.
772 This includes <a href="LangRef.html#memoryops">atomic load and store,
773 compare and exchange, and read/modify/write instructions</a> as well as a
774 full set of <a href="LangRef.html#ordering">memory ordering constraints</a>.
775 Please see the <a href="Atomics.html">Atomics Guide</a> for more
776 information.
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]777</li>
778<li>The LLVM IR exception handling representation has been redesigned and
779 reimplemented, making it more elegant, fixing a huge number of bugs, and
780 enabling inlining and other optimizations. Please see its blog post (XXX
Chris Lattner064caf92011-11-27 21:30:28 +0000[diff] [blame]781 not yet) and the <a href="ExceptionHandling.html">Exception Handling
782 documentation</a> for more information.</li>
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]783<li>The LLVM IR Type system has been redesigned and reimplemented, making it
784 faster and solving some long-standing problems.
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]785 Please see its <a
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]786 href="http://blog.llvm.org/2011/11/llvm-30-type-system-rewrite.html">blog
787 post</a> for more information.</li>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]788
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]789<li>The MIPS backend has made major leaps in this release, going from an
Chris Lattner064caf92011-11-27 21:30:28 +0000[diff] [blame]790 experimental target to being virtually production quality and supporting a
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]791 wide variety of MIPS subtargets. See the <a href="#MIPS">MIPS section</a>
792 below for more information.</li>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]793
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]794<li>The optimizer and code generator now supports gprof and gcov-style coverage
Chris Lattner064caf92011-11-27 21:30:28 +0000[diff] [blame]795 and profiling information, and includes a new llvm-cov tool (but also works
796 with gcov). Clang exposes coverage and profiling through GCC-compatible
797 command line options.</li>
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000[diff] [blame]798</ul>
Mikhail Glushenkovea65d7d2008-10-13 02:08:34 +0000[diff] [blame]799
Bill Wendlingbc5f6dd2011-10-26 18:33:01 +0000[diff] [blame]800</div>
801
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]802
Chris Lattner4f0fe432011-11-27 19:26:30 +0000[diff] [blame]803<!--=========================================================================-->
804<h3>
805<a name="coreimprovements">LLVM IR and Core Improvements</a>
806</h3>
807
808<div>
809
810<p>LLVM IR has several new features for better support of new targets and that
811 expose new optimization opportunities:</p>
812
Chris Lattner064caf92011-11-27 21:30:28 +0000[diff] [blame]813 <ul>
814 <li><a href="Atomics.html">Atomic memory accesses and memory ordering</a> are
815 now directly expressible in the IR.</li>
816 <li>A new <a href="LangRef.html#int_fma">llvm.fma intrinsic</a> directly
817 represents floating point multiply accumulate operations without an
818 intermediate rounding stage.</li>
819 <li>A new llvm.expect intrinsic (XXX not documented in langref) allows a
820 frontend to express expected control flow (and the __builtin_expect builtin
821 from GNU C).</li>
822 <li>The <a href="LangRef.html#int_prefetch">llvm.prefetch intrinsic</a> now
823 takes a 4th argument that specifies whether the prefetch happens from the
824 icache or dcache.</li>
825 <li>The new <a href="LangRef.html#uwtable">uwtable function attribute</a>
826 allows a frontend to control emission of unwind tables.</li>
827 <li>The new <a href="LangRef.html#fnattrs">nonlazybind function
828 attribute</a> allow optimization of Global Offset Table (GOT) accesses.</li>
829 <li>The new <a href="LangRef.html#returns_twice">returns_twice attribute</a>
830 allows better modeling of functions like setjmp.</li>
831 <li>The <a href="LangRef.html#datalayout">target datalayout</a> string can now
832 encode the natural alignment of the target's stack for better optimization.
833 </li>
834 </ul>
Andrew Trick5aab6382011-11-06 17:59:24 +0000[diff] [blame]835</div>
836
837<!--=========================================================================-->
838<h3>
Chris Lattneracce85d2008-02-10 07:46:44 +0000[diff] [blame]839<a name="optimizer">Optimizer Improvements</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]840</h3>
Chris Lattneracce85d2008-02-10 07:46:44 +0000[diff] [blame]841
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]842<div>
Chris Lattneracce85d2008-02-10 07:46:44 +0000[diff] [blame]843
Chris Lattner064caf92011-11-27 21:30:28 +0000[diff] [blame]844<p>In addition to many minor performance tweaks and bug fixes, this
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]845 release includes a few major enhancements and additions to the
846 optimizers:</p>
Chris Lattneracce85d2008-02-10 07:46:44 +0000[diff] [blame]847
848<ul>
Chris Lattner064caf92011-11-27 21:30:28 +0000[diff] [blame]849<li>The pass manager now has an extension API that allows front-ends and plugins
850 to insert their own optimizations in the well-known places in the standard
851 pass optimization pipeline.</li>
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]852
Benjamin Kramer933a78c2011-11-26 11:14:54 +0000[diff] [blame]853<li>Information about <a href="BranchWeightMetadata.html">branch probability</a>
854 and basic block frequency is now available within LLVM, based on a
855 combination of static branch prediction heuristics and
856 <code>__builtin_expect</code> calls. That information is currently used for
857 register spill placement and if-conversion, with additional optimizations
858 planned for future releases. The same framework is intended for eventual
859 use with profile-guided optimization.</li>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]860
Chris Lattner064caf92011-11-27 21:30:28 +0000[diff] [blame]861<li>The "-indvars" induction variable simplification pass only modifies
862 induction variables when profitable. Sign and zero extension
863 elimination, linear function test replacement, loop unrolling, and
864 other simplifications that require induction variable analysis have
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]865 been generalized so they no longer require loops to be rewritten into
Chris Lattner064caf92011-11-27 21:30:28 +0000[diff] [blame]866 canonical form prior to optimization. This new design
867 preserves more IR level information, avoids undoing earlier loop
868 optimizations (particularly hand-optimized loops), and no longer
869 requires the code generator to reconstruct loops into an optimal form -
870 an intractable problem.</li>
871
872<li>LLVM now includes a pass to optimize retain/release calls for the
873 <a href="http://clang.llvm.org/docs/AutomaticReferenceCounting.html">Automatic
874 Reference Counting</a> (ARC) Objective-C language feature (in
Chris Lattner2f206022011-11-27 22:03:34 +0000[diff] [blame]875 lib/Transforms/Scalar/ObjCARC.cpp). It is a decent example of implementing
876 a source-language-specific optimization in LLVM.</li>
Chris Lattner064caf92011-11-27 21:30:28 +0000[diff] [blame]877
Chris Lattner11b66112010-10-04 02:42:39 +0000[diff] [blame]878</ul>
879
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]880</div>
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]881
Chris Lattner0b832202008-06-08 02:45:07 +0000[diff] [blame]882<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]883<h3>
Chris Lattner4ba2b652010-09-30 16:31:33 +0000[diff] [blame]884<a name="mc">MC Level Improvements</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]885</h3>
Chris Lattner4ba2b652010-09-30 16:31:33 +0000[diff] [blame]886
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]887<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]888
889<p>The LLVM Machine Code (aka MC) subsystem was created to solve a number of
890 problems in the realm of assembly, disassembly, object file format handling,
891 and a number of other related areas that CPU instruction-set level tools work
Chris Lattner2f206022011-11-27 22:03:34 +0000[diff] [blame]892 in. For more information, please see
893 the <a href="http://blog.llvm.org/2010/04/intro-to-llvm-mc-project.html">Intro
894 to the LLVM MC Project Blog Post</a>.</p>
Chris Lattner7d9b6b42010-10-02 21:59:30 +0000[diff] [blame]895
Chris Lattner7d9b6b42010-10-02 21:59:30 +0000[diff] [blame]896<ul>
Chris Lattner2f206022011-11-27 22:03:34 +0000[diff] [blame]897 <li>The MC layer has undergone significant refactoring to eliminate layering
898 violations that caused it to pull in the LLVM compiler backend code.</li>
899 <li>The ELF object file writers are much more full featured.</li>
900 <li>The integrated assembler now supports #line directives.</li>
901 <li>An early implementation of a JIT built on top of the MC framework (known
902 as MC-JIT) has been implemented and will eventually replace the old JIT.
903 It emits object files direct to memory and uses a runtime dynamic linker to
904 resolve references and drive lazy compilation. The MC-JIT enables much
905 greater code reuse between the JIT and the static compiler and provides
906 better integration with the platform ABI as a result.
907 </li>
908 <li>The assembly printer now makes uses of assemblers instruction aliases
909 (InstAliases) to print simplified mneumonics when possible.</li>
910 <li>TableGen can now autogenerate MC expansion logic for pseudo
911 instructions that expand to multiple MC instructions (through the
912 PseudoInstExpansion class).</li>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]913 <li>A new llvm-dwarfdump tool provides a start of a drop-in
914 replacement for the corresponding tool that use LLVM libraries. As part of
Chris Lattner7c224462011-11-27 22:39:23 +0000[diff] [blame]915 this, LLVM has the beginnings of a dwarf parsing library.</li>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]916 <li>llvm-objdump has more output including, symbol by symbol disassembly,
917 inline relocations, section headers, symbol tables, and section contents.
918 Support for archive files has also been added.</li>
919 <li>llvm-nm has gained support for archives of binary files.</li>
920 <li>llvm-size has been added. This tool prints out section sizes.</li>
Chris Lattner7d9b6b42010-10-02 21:59:30 +0000[diff] [blame]921</ul>
922
NAKAMURA Takumi45c435a2011-04-05 08:24:22 +0000[diff] [blame]923</div>
Chris Lattner4ba2b652010-09-30 16:31:33 +0000[diff] [blame]924
Chris Lattner4ba2b652010-09-30 16:31:33 +0000[diff] [blame]925<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]926<h3>
Chris Lattner511433e2009-03-02 03:24:11 +0000[diff] [blame]927<a name="codegen">Target Independent Code Generator Improvements</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]928</h3>
Chris Lattner0b832202008-06-08 02:45:07 +0000[diff] [blame]929
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]930<div>
Chris Lattner0b832202008-06-08 02:45:07 +0000[diff] [blame]931
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000[diff] [blame]932<p>We have put a significant amount of work into the code generator
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]933 infrastructure, which allows us to implement more aggressive algorithms and
934 make it run faster:</p>
Chris Lattner0b832202008-06-08 02:45:07 +0000[diff] [blame]935
936<ul>
Chris Lattner1cc489b2011-11-27 22:12:32 +0000[diff] [blame]937<li>XXX: Segmented stacks.</li>
Chris Lattner2f206022011-11-27 22:03:34 +0000[diff] [blame]938<li>LLVM generates substantially better code for indirect gotos due to a new
939 tail duplication pass, which can be a substantial performance win for
940 interpreter loops that use them.</li>
941<li>Exception handling and debug information is now emitted with CFI directives,
942 yielding <a href="http://blog.mozilla.com/respindola/2011/05/12/cfi-directives/">much smaller executables</a> for some C++ applications.
943</li>
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]944
Chris Lattner2f206022011-11-27 22:03:34 +0000[diff] [blame]945<li>The code generator now supports vector "select" operations on vector
946 comparisons, turning them into various optimized code sequences (e.g.
947 using the SSE4/AVX "blend" instructions).</li>
Jakob Stoklund Olesen09e61ca2011-11-28 01:46:19 +0000[diff] [blame]948<li>The SSE execution domain fix pass and the ARM NEON move fix pass have been
Jakob Stoklund Olesen87f95dc2011-11-28 18:03:11 +0000[diff] [blame]949 merged to a target independent execution dependency fix pass. This pass is
950 used to select alternative equivalent opcodes in a way that minimizes
951 execution domain crossings. Closely connected instructions are moved to
952 the same execution domain when possible. Targets can override the
953 <code>getExecutionDomain</code> and <code>setExecutionDomain</code> hooks
954 to use the pass.</li>
Chris Lattner84977642007-09-21 03:54:09 +0000[diff] [blame]955</ul>
Chris Lattner84977642007-09-21 03:54:09 +0000[diff] [blame]956</div>
957
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]958<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]959<h3>
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]960<a name="x86">X86-32 and X86-64 Target Improvements</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]961</h3>
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]962
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]963<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]964
965<p>New features and major changes in the X86 target include:</p>
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]966
967<ul>
Chris Lattner2f206022011-11-27 22:03:34 +0000[diff] [blame]968<li>The X86 backend, assembler and disassembler now have full support for AVX 1.
969 To enable it pass <code>-mavx</code> to the compiler. AVX2 implementation is
970 underway on mainline.</li>
971<li>The integrated assembler and disassembler now support a broad range of new
972 instructions including Atom, Ivy Bridge, <a
973 href="http://en.wikipedia.org/wiki/SSE4a">SSE4a/BMI</a> instructions, <a
974 href="http://en.wikipedia.org/wiki/RdRand">rdrand</a> and many others.</li>
975<li>The X86 backend now fully supports the <a href="http://llvm.org/PR879">X87
976 floating point stack inline assembly constraints</a>.</li>
977<li>The integrated assembler now supports the <tt>.code32</tt> and
978 <tt>.code64</tt> directives to switch between 32-bit and 64-bit
979 instructions.</li>
980<li>The X86 backend now synthesizes horizontal add/sub instructions from generic
981 vector code when the appropriate instructions are enabled.</li>
982<li>The X86-64 backend generates smaller and faster code at -O0 due to
983 improvements in fast instruction selection.</li>
984<li><a href="http://code.google.com/p/nativeclient/">Native Client</a>
985 subtarget support has been added.</li>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]986
Chris Lattner2f206022011-11-27 22:03:34 +0000[diff] [blame]987<li>The CRC32 intrinsics have been renamed. The intrinsics were previously
988 <code>@llvm.x86.sse42.crc32.[8|16|32]</code>
989 and <code>@llvm.x86.sse42.crc64.[8|64]</code>. They have been renamed to
990 <code>@llvm.x86.sse42.crc32.32.[8|16|32]</code> and
991 <code>@llvm.x86.sse42.crc32.64.[8|64]</code>.</li>
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]992</ul>
993
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]994</div>
Chris Lattner84977642007-09-21 03:54:09 +0000[diff] [blame]995
996<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]997<h3>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]998<a name="ARM">ARM Target Improvements</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]999</h3>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000[diff] [blame]1000
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]1001<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]1002
1003<p>New features of the ARM target include:</p>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000[diff] [blame]1004
1005<ul>
Chris Lattner1cc489b2011-11-27 22:12:32 +0000[diff] [blame]1006<li>The ARM backend generates much faster code for Cortex-A9 chips.</li>
1007<li>The ARM backend has improved support for Cortex-M series processors.</li>
1008<li>The ARM inline assembly constraints have been implemented and are now fully
1009 supported.</li>
1010<li>NEON code produced by Clang often runs much faster due to improvements in
1011 the Scalar Replacement of Aggregates pass.</li>
1012<li>The old ARM disassembler is replaced with a new one based on autogenerated
1013 encoding information from ARM .td files.</li>
1014<li>The integrated assembler has made major leaps forward, but is still beta quality in LLVM 3.0.</li>
Bob Wilsone8472772010-09-13 17:39:35 +0000[diff] [blame]1015</ul>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]1016</div>
Chris Lattner7b95c382011-11-15 22:23:46 +0000[diff] [blame]1017
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]1018
Chris Lattner1efe27e2011-04-06 00:45:11 +0000[diff] [blame]1019<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]1020<h3>
Akira Hatanaka5381cbf2011-11-15 21:33:05 +0000[diff] [blame]1021<a name="MIPS">MIPS Target Improvements</a>
1022</h3>
1023
1024<div>
1025
Chris Lattner1cc489b2011-11-27 22:12:32 +0000[diff] [blame]1026<p>This release has seen major new work on just about every aspect of the MIPS
1027 backend. Some of the major new features include:</p>
Akira Hatanaka5381cbf2011-11-15 21:33:05 +0000[diff] [blame]1028
1029<ul>
1030 <li>Most MIPS32r1 and r2 instructions are now supported.</li>
1031 <li>LE/BE MIPS32r1/r2 has been tested extensively.</li>
1032 <li>O32 ABI has been fully tested.</li>
1033 <li>MIPS backend has migrated to using the MC infrastructure for assembly printing. Initial support for direct object code emission has been implemented too.</li>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]1034 <li>Delay slot filler has been updated. Now it tries to fill delay slots with useful instructions instead of always filling them with NOPs.</li>
Akira Hatanaka5381cbf2011-11-15 21:33:05 +0000[diff] [blame]1035 <li>Support for old-style JIT is complete.</li>
1036 <li>Support for old architectures (MIPS1 and MIPS2) has been removed.</li>
1037 <li>Initial support for MIPS64 has been added.</li>
1038</ul>
1039</div>
Chris Lattner7b95c382011-11-15 22:23:46 +0000[diff] [blame]1040
1041<!--=========================================================================-->
1042<h3>
1043 <a name="PTX">PTX Target Improvements</a>
1044</h3>
1045
1046<div>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]1047
Chris Lattner7b95c382011-11-15 22:23:46 +0000[diff] [blame]1048 <p>
1049 The PTX back-end is still experimental, but is fairly usable for compute kernels
1050 in LLVM 3.0. Most scalar arithmetic is implemented, as well as intrinsics to
1051 access the special PTX registers and sync instructions. The major missing
1052 pieces are texture/sampler support and some vector operations.</p>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]1053
Chris Lattner7b95c382011-11-15 22:23:46 +0000[diff] [blame]1054 <p>That said, the backend is already being used for domain-specific languages
1055 and works well with the <a href="http://www.pcc.me.uk/~peter/libclc/">libclc
1056 library</a> to supply OpenCL built-ins. With it, you can use Clang to compile
1057 OpenCL code into PTX and execute it by loading the resulting PTX as a binary
1058 blob using the nVidia OpenCL library. It has been tested with several OpenCL
1059 programs, including some from the nVidia GPU Computing SDK, and the performance
1060 is on par with the nVidia compiler.</p>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]1061
Chris Lattner7b95c382011-11-15 22:23:46 +0000[diff] [blame]1062</div>
1063
Akira Hatanaka5381cbf2011-11-15 21:33:05 +0000[diff] [blame]1064<!--=========================================================================-->
1065<h3>
Chris Lattner1efe27e2011-04-06 00:45:11 +0000[diff] [blame]1066<a name="OtherTS">Other Target Specific Improvements</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]1067</h3>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000[diff] [blame]1068
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]1069<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]1070
Chris Lattner1efe27e2011-04-06 00:45:11 +0000[diff] [blame]1071<ul>
Chris Lattnerd6cc2c22011-11-27 22:36:22 +0000[diff] [blame]1072<li>Many PowerPC improvements have been implemented for ELF targets, including
1073 support for varargs and initial support for direct .o file emission.</li>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]1074
Chris Lattnerd6cc2c22011-11-27 22:36:22 +0000[diff] [blame]1075<li>MicroBlaze scheduling itineraries were added that model the
1076 3-stage and the 5-stage pipeline architectures. The 3-stage
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]1077 pipeline model can be selected with <code>-mcpu=mblaze3</code>
1078 and the 5-stage pipeline model can be selected with
Chris Lattnerd6cc2c22011-11-27 22:36:22 +0000[diff] [blame]1079 <code>-mcpu=mblaze5</code>.</li>
1080
Chris Lattner1efe27e2011-04-06 00:45:11 +0000[diff] [blame]1081</ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]1082
Chris Lattner1efe27e2011-04-06 00:45:11 +0000[diff] [blame]1083</div>
Chris Lattner77d29b12008-06-05 08:02:49 +0000[diff] [blame]1084
1085<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]1086<h3>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]1087<a name="changes">Major Changes and Removed Features</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]1088</h3>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]1089
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]1090<div>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]1091
Bill Wendling2626dba2011-08-03 22:18:20 +0000[diff] [blame]1092<p>If you're already an LLVM user or developer with out-of-tree changes based on
1093 LLVM 2.9, this section lists some "gotchas" that you may run into upgrading
1094 from the previous release.</p>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]1095
1096<ul>
Chris Lattnerd6cc2c22011-11-27 22:36:22 +0000[diff] [blame]1097<li>LLVM 3.0 removes support for reading LLVM 2.8 and earlier files, and LLVM
1098 3.1 will eliminate support for reading LLVM 2.9 files. Going forward, we
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]1099 aim for all future versions of LLVM to read bitcode files and .ll files
Chris Lattnerd6cc2c22011-11-27 22:36:22 +0000[diff] [blame]1100 produced by LLVM 3.0.</li>
1101<li>Tablegen has been split into a library, allowing the clang tblgen pieces
1102 now live in the clang tree. The llvm version has been renamed to
1103 llvm-tblgen instead of tblgen.</li>
Chris Lattner5a1731d2011-11-27 08:32:32 +0000[diff] [blame]1104 <li>The <code>LLVMC</code> meta compiler driver was removed.</li>
Chris Lattnerd6cc2c22011-11-27 22:36:22 +0000[diff] [blame]1105 <li>The unused PostOrder Dominator Frontiers and LowerSetJmp passes were removed.</li>
1106
1107
Rafael Espindolaf940a1a2011-08-30 23:03:45 +0000[diff] [blame]1108 <li>The old <code>TailDup</code> pass was not used in the standard pipeline
1109 and was unable to update ssa form, so it has been removed.
Eli Friedmanf03bb262011-08-12 22:50:01 +0000[diff] [blame]1110 <li>The syntax of volatile loads and stores in IR has been changed to
1111 "<code>load volatile</code>"/"<code>store volatile</code>". The old
1112 syntax ("<code>volatile load</code>"/"<code>volatile store</code>")
Chris Lattnerd6cc2c22011-11-27 22:36:22 +0000[diff] [blame]1113 is still accepted, but is now considered deprecated and will be removed in
1114 3.1.</li>
1115 <li>llvm-gcc's frontend tests have been removed from llvm/test/Frontend*, sunk
1116 into the clang and dragonegg testsuites.</li>
Benjamin Kramer7c5025b2011-11-25 21:26:00 +0000[diff] [blame]1117 <li>The old atomic intrinsics (<code>llvm.memory.barrier</code> and
Eli Friedman526e1bb2011-10-26 00:55:23 +0000[diff] [blame]1118 <code>llvm.atomic.*</code>) are now gone. Please use the new atomic
1119 instructions, described in the <a href="Atomics.html">atomics guide</a>.
Chris Lattnerd6cc2c22011-11-27 22:36:22 +0000[diff] [blame]1120 <li>LLVM's configure script doesn't depend on llvm-gcc anymore, eliminating a
1121 strange circular dependence between projects.</li>
Devang Patelb34dd132008-10-14 20:03:43 +0000[diff] [blame]1122</ul>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]1123
NAKAMURA Takumi2026de22011-08-22 23:22:05 +0000[diff] [blame]1124<h4>Windows (32-bit)</h4>
1125<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]1126
NAKAMURA Takumi2026de22011-08-22 23:22:05 +0000[diff] [blame]1127<ul>
1128 <li>On Win32(MinGW32 and MSVC), Windows 2000 will not be supported.
1129 Windows XP or higher is required.</li>
1130</ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]1131
NAKAMURA Takumi2026de22011-08-22 23:22:05 +0000[diff] [blame]1132</div>
1133
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]1134</div>
1135
Daniel Dunbarf0233c62010-10-04 20:11:41 +0000[diff] [blame]1136<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]1137<h3>
Chris Lattner1efe27e2011-04-06 00:45:11 +0000[diff] [blame]1138<a name="api_changes">Internal API Changes</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]1139</h3>
Daniel Dunbarf0233c62010-10-04 20:11:41 +0000[diff] [blame]1140
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]1141<div>
Daniel Dunbarf0233c62010-10-04 20:11:41 +0000[diff] [blame]1142
Chris Lattner1efe27e2011-04-06 00:45:11 +0000[diff] [blame]1143<p>In addition, many APIs have changed in this release. Some of the major
Bill Wendling16005252011-08-02 06:20:17 +0000[diff] [blame]1144 LLVM API changes are:</p>
Daniel Dunbarf0233c62010-10-04 20:11:41 +0000[diff] [blame]1145
1146<ul>
Benjamin Kramer7c5025b2011-11-25 21:26:00 +0000[diff] [blame]1147 <li>The biggest and most pervasive change is that llvm::Types are no longer
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]1148 returned or accepted as 'const' values. Instead, just pass around
Benjamin Kramer7c5025b2011-11-25 21:26:00 +0000[diff] [blame]1149 non-const Types.</li>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]1150
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]1151 <li><code>PHINode::reserveOperandSpace</code> has been removed. Instead, you
1152 must specify how many operands to reserve space for when you create the
1153 PHINode, by passing an extra argument
1154 into <code>PHINode::Create</code>.</li>
Jay Foad558d3762011-07-14 09:19:05 +0000[diff] [blame]1155
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]1156 <li>PHINodes no longer store their incoming BasicBlocks as operands. Instead,
1157 the list of incoming BasicBlocks is stored separately, and can be accessed
1158 with new functions <code>PHINode::block_begin</code>
1159 and <code>PHINode::block_end</code>.</li>
Jay Foad558d3762011-07-14 09:19:05 +0000[diff] [blame]1160
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]1161 <li>Various functions now take an <code>ArrayRef</code> instead of either a
1162 pair of pointers (or iterators) to the beginning and end of a range, or a
1163 pointer and a length. Others now return an <code>ArrayRef</code> instead
1164 of a reference to a <code>SmallVector</code>
1165 or <code>std::vector</code>. These include:
Jay Foad558d3762011-07-14 09:19:05 +0000[diff] [blame]1166<ul>
1167<!-- Please keep this list sorted. -->
Jay Foada3efbb12011-07-15 08:37:34 +0000[diff] [blame]1168<li><code>CallInst::Create</code></li>
Jay Foad558d3762011-07-14 09:19:05 +0000[diff] [blame]1169<li><code>ComputeLinearIndex</code> (in <code>llvm/CodeGen/Analysis.h</code>)</li>
1170<li><code>ConstantArray::get</code></li>
1171<li><code>ConstantExpr::getExtractElement</code></li>
Jay Foaddab3d292011-07-21 14:31:17 +0000[diff] [blame]1172<li><code>ConstantExpr::getGetElementPtr</code></li>
1173<li><code>ConstantExpr::getInBoundsGetElementPtr</code></li>
Jay Foad558d3762011-07-14 09:19:05 +0000[diff] [blame]1174<li><code>ConstantExpr::getIndices</code></li>
1175<li><code>ConstantExpr::getInsertElement</code></li>
1176<li><code>ConstantExpr::getWithOperands</code></li>
Jay Foad1d2f5692011-07-19 13:32:40 +0000[diff] [blame]1177<li><code>ConstantFoldCall</code> (in <code>llvm/Analysis/ConstantFolding.h</code>)</li>
1178<li><code>ConstantFoldInstOperands</code> (in <code>llvm/Analysis/ConstantFolding.h</code>)</li>
Jay Foad558d3762011-07-14 09:19:05 +0000[diff] [blame]1179<li><code>ConstantVector::get</code></li>
1180<li><code>DIBuilder::createComplexVariable</code></li>
1181<li><code>DIBuilder::getOrCreateArray</code></li>
1182<li><code>ExtractValueInst::Create</code></li>
1183<li><code>ExtractValueInst::getIndexedType</code></li>
1184<li><code>ExtractValueInst::getIndices</code></li>
1185<li><code>FindInsertedValue</code> (in <code>llvm/Analysis/ValueTracking.h</code>)</li>
Jay Foadca12a212011-07-19 14:42:50 +0000[diff] [blame]1186<li><code>gep_type_begin</code> (in <code>llvm/Support/GetElementPtrTypeIterator.h</code>)</li>
1187<li><code>gep_type_end</code> (in <code>llvm/Support/GetElementPtrTypeIterator.h</code>)</li>
Jay Foada9203102011-07-25 09:48:08 +0000[diff] [blame]1188<li><code>GetElementPtrInst::Create</code></li>
1189<li><code>GetElementPtrInst::CreateInBounds</code></li>
1190<li><code>GetElementPtrInst::getIndexedType</code></li>
Jay Foadb60e8512011-07-21 14:42:51 +0000[diff] [blame]1191<li><code>InsertValueInst::Create</code></li>
1192<li><code>InsertValueInst::getIndices</code></li>
1193<li><code>InvokeInst::Create</code></li>
Jay Foada3efbb12011-07-15 08:37:34 +0000[diff] [blame]1194<li><code>IRBuilder::CreateCall</code></li>
Jay Foad558d3762011-07-14 09:19:05 +0000[diff] [blame]1195<li><code>IRBuilder::CreateExtractValue</code></li>
Jay Foad0a2a60a2011-07-22 08:16:57 +0000[diff] [blame]1196<li><code>IRBuilder::CreateGEP</code></li>
1197<li><code>IRBuilder::CreateInBoundsGEP</code></li>
Jay Foad558d3762011-07-14 09:19:05 +0000[diff] [blame]1198<li><code>IRBuilder::CreateInsertValue</code></li>
Jay Foada3efbb12011-07-15 08:37:34 +0000[diff] [blame]1199<li><code>IRBuilder::CreateInvoke</code></li>
Jay Foad558d3762011-07-14 09:19:05 +0000[diff] [blame]1200<li><code>MDNode::get</code></li>
1201<li><code>MDNode::getIfExists</code></li>
1202<li><code>MDNode::getTemporary</code></li>
1203<li><code>MDNode::getWhenValsUnresolved</code></li>
Jay Foadb9b54eb2011-07-19 15:07:52 +0000[diff] [blame]1204<li><code>SimplifyGEPInst</code> (in <code>llvm/Analysis/InstructionSimplify.h</code>)</li>
Jay Foad8fbbb392011-07-19 14:01:37 +0000[diff] [blame]1205<li><code>TargetData::getIndexedOffset</code></li>
Jay Foad558d3762011-07-14 09:19:05 +0000[diff] [blame]1206</ul></li>
1207
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]1208 <li>All forms of <code>StringMap::getOrCreateValue</code> have been remove
1209 except for the one which takes a <code>StringRef</code>.</li>
Jay Foad558d3762011-07-14 09:19:05 +0000[diff] [blame]1210
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]1211 <li>The <code>LLVMBuildUnwind</code> function from the C API was removed. The
1212 LLVM <code>unwind</code> instruction has been deprecated for a long time
1213 and isn't used by the current front-ends. So this was removed during the
1214 exception handling rewrite.</li>
Bill Wendling16005252011-08-02 06:20:17 +0000[diff] [blame]1215
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]1216 <li>The <code>LLVMAddLowerSetJmpPass</code> function from the C API was
1217 removed because the <code>LowerSetJmp</code> pass was removed.</li>
Bill Wendling2626dba2011-08-03 22:18:20 +0000[diff] [blame]1218
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]1219 <li>The <code>DIBuilder</code> interface used by front ends to encode
1220 debugging information in the LLVM IR now expects clients to
1221 use <code>DIBuilder::finalize()</code> at the end of translation unit to
1222 complete debugging information encoding.</li>
Devang Patel6326a422011-08-15 23:00:00 +0000[diff] [blame]1223
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]1224 <li>The way the type system works has been
1225 rewritten: <code>PATypeHolder</code> and <code>OpaqueType</code> are gone,
1226 and all APIs deal with <code>Type*</code> instead of <code>const
1227 Type*</code>. If you need to create recursive structures, then create a
1228 named structure, and use <code>setBody()</code> when all its elements are
1229 built. Type merging and refining is gone too: named structures are not
1230 merged with other structures, even if their layout is identical. (of
1231 course anonymous structures are still uniqued by layout).</li>
Torok Edwinf16e2d42011-09-30 13:07:52 +0000[diff] [blame]1232
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]1233 <li>TargetSelect.h moved to Support/ from Target/</li>
Torok Edwinf16e2d42011-09-30 13:07:52 +0000[diff] [blame]1234
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]1235 <li>UpgradeIntrinsicCall no longer upgrades pre-2.9 intrinsic calls (for
1236 example <code>llvm.memset.i32</code>).</li>
Torok Edwinf16e2d42011-09-30 13:07:52 +0000[diff] [blame]1237
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]1238 <li>It is mandatory to initialize all out-of-tree passes too and their dependencies now with
1239 <code>INITIALIZE_PASS{BEGIN,END,}</code>
1240 and <code>INITIALIZE_{PASS,AG}_DEPENDENCY</code>.</li>
Torok Edwinf16e2d42011-09-30 13:07:52 +0000[diff] [blame]1241
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]1242 <li>The interface for MemDepResult in MemoryDependenceAnalysis has been
1243 enhanced with new return types Unknown and NonFuncLocal, in addition to
1244 the existing types Clobber, Def, and NonLocal.</li>
Daniel Dunbarf0233c62010-10-04 20:11:41 +0000[diff] [blame]1245</ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]1246
Daniel Dunbarf0233c62010-10-04 20:11:41 +0000[diff] [blame]1247</div>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]1248
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]1249</div>
1250
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]1251<!-- *********************************************************************** -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]1252<h2>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1253 <a name="knownproblems">Known Problems</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]1254</h2>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]1255<!-- *********************************************************************** -->
1256
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]1257<div>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1258
Chris Lattner70e22012011-11-27 19:38:20 +0000[diff] [blame]1259<p>LLVM is generally a production quality compiler, and is used by a broad range
1260 of applications and shipping in many products. That said, not every
1261 subsystem is as mature as the aggregate, particularly the more obscure
1262 targets. If you run into a problem, please check the <a
1263 href="http://llvm.org/bugs/">LLVM bug database</a> and submit a bug if
1264 there isn't already one or ask on the <a
1265 href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev
1266 list</a>.</p>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]1267
Chris Lattner70e22012011-11-27 19:38:20 +0000[diff] [blame]1268 <p>Known problem areas include:</p>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]1269
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]1270<ul>
Chris Lattner70e22012011-11-27 19:38:20 +0000[diff] [blame]1271 <li>The Alpha, Blackfin, CellSPU, MSP430, PTX, SystemZ and
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]1272 XCore backends are experimental, and the Alpha, Blackfin and SystemZ
1273 targets have already been removed from mainline.</li>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]1274
Chris Lattner70e22012011-11-27 19:38:20 +0000[diff] [blame]1275 <li>The integrated assembler, disassembler, and JIT is not supported by
1276 several targets. If an integrated assembler is not supported, then a
1277 system assembler is required. For more details, see the <a
1278 href="CodeGenerator.html#targetfeatures">Target Features Matrix</a>.
1279 </li>
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]1280
Chris Lattner70e22012011-11-27 19:38:20 +0000[diff] [blame]1281 <li>The C backend has numerous problems and is not being actively maintained.
1282 Depending on it for anything serious is not advised.</li>
Chris Lattner26299222006-11-18 07:51:14 +0000[diff] [blame]1283</ul>
1284
1285</div>
John Criswellc0c186d2005-11-08 21:11:33 +0000[diff] [blame]1286
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]1287</div>
1288
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]1289<!-- *********************************************************************** -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]1290<h2>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1291 <a name="additionalinfo">Additional Information</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000[diff] [blame]1292</h2>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]1293<!-- *********************************************************************** -->
1294
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000[diff] [blame]1295<div>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1296
Bill Wendling7b7fa742011-10-26 18:46:16 +0000[diff] [blame]1297<p>A wide variety of additional information is available on
1298 the <a href="http://llvm.org/">LLVM web page</a>, in particular in
1299 the <a href="http://llvm.org/docs/">documentation</a> section. The web page
1300 also contains versions of the API documentation which is up-to-date with the
1301 Subversion version of the source code. You can access versions of these
1302 documents specific to this release by going into the "<tt>llvm/doc/</tt>"
1303 directory in the LLVM tree.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]1304
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1305<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]1306 us via the <a href="http://llvm.org/docs/#maillist"> mailing lists</a>.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]1307
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1308</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]1309
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]1310<!--=========================================================================-->
1311
1312<!-- EH details: to be moved to a blog post:
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]1313
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]1314
1315
1316
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]1317<p>One of the biggest changes is that 3.0 has a new exception handling
1318 system. The old system used LLVM intrinsics to convey the exception handling
1319 information to the code generator. It worked in most cases, but not
1320 all. Inlining was especially difficult to get right. Also, the intrinsics
1321 could be moved away from the <code>invoke</code> instruction, making it hard
1322 to recover that information.</p>
1323
1324<p>The new EH system makes exception handling a first-class member of the IR. It
1325 adds two new instructions:</p>
1326
1327<ul>
1328 <li><a href="LangRef.html#i_landingpad"><code>landingpad</code></a> &mdash;
1329 this instruction defines a landing pad basic block. It contains all of the
1330 information that's needed by the code generator. It's also required to be
1331 the first non-PHI instruction in the landing pad. In addition, a landing
1332 pad may be jumped to only by the unwind edge of an <code>invoke</code>
1333 instruction.</li>
1334
1335 <li><a href="LangRef.html#i_resume"><code>resume</code></a> &mdash; this
1336 instruction causes the current exception to resume traveling up the
1337 stack. It replaces the <code>@llvm.eh.resume</code> intrinsic.</li>
1338</ul>
1339
1340<p>Converting from the old EH API to the new EH API is rather simple, because a
1341 lot of complexity has been removed. The two intrinsics,
1342 <code>@llvm.eh.exception</code> and <code>@llvm.eh.selector</code> have been
1343 superseded by the <code>landingpad</code> instruction. Instead of generating
1344 a call to <code>@llvm.eh.exception</code> and <code>@llvm.eh.selector</code>:
1345
1346<div class="doc_code">
1347<pre>
1348Function *ExcIntr = Intrinsic::getDeclaration(TheModule,
1349 Intrinsic::eh_exception);
1350Function *SlctrIntr = Intrinsic::getDeclaration(TheModule,
1351 Intrinsic::eh_selector);
1352
1353// The exception pointer.
1354Value *ExnPtr = Builder.CreateCall(ExcIntr, "exc_ptr");
1355
1356std::vector&lt;Value*&gt; Args;
1357Args.push_back(ExnPtr);
1358Args.push_back(Builder.CreateBitCast(Personality,
1359 Type::getInt8PtrTy(Context)));
1360
1361<i>// Add selector clauses to Args.</i>
1362
1363// The selector call.
1364Builder.CreateCall(SlctrIntr, Args, "exc_sel");
1365</pre>
1366</div>
1367
1368<p>You should instead generate a <code>landingpad</code> instruction, that
1369 returns an exception object and selector value:</p>
1370
1371<div class="doc_code">
1372<pre>
1373LandingPadInst *LPadInst =
1374 Builder.CreateLandingPad(StructType::get(Int8PtrTy, Int32Ty, NULL),
1375 Personality, 0);
1376
1377Value *LPadExn = Builder.CreateExtractValue(LPadInst, 0);
1378Builder.CreateStore(LPadExn, getExceptionSlot());
1379
1380Value *LPadSel = Builder.CreateExtractValue(LPadInst, 1);
1381Builder.CreateStore(LPadSel, getEHSelectorSlot());
1382</pre>
1383</div>
1384
1385<p>It's now trivial to add the individual clauses to the <code>landingpad</code>
1386 instruction.</p>
1387
1388<div class="doc_code">
1389<pre>
1390<i><b>// Adding a catch clause</b></i>
1391Constant *TypeInfo = getTypeInfo();
1392LPadInst-&gt;addClause(TypeInfo);
1393
1394<i><b>// Adding a C++ catch-all</b></i>
1395LPadInst-&gt;addClause(Constant::getNullValue(Builder.getInt8PtrTy()));
1396
1397<i><b>// Adding a cleanup</b></i>
1398LPadInst-&gt;setCleanup(true);
1399
1400<i><b>// Adding a filter clause</b></i>
1401std::vector&lt;Constant*&gt; TypeInfos;
1402Constant *TypeInfo = getFilterTypeInfo();
1403TypeInfos.push_back(Builder.CreateBitCast(TypeInfo, Builder.getInt8PtrTy()));
1404
1405ArrayType *FilterTy = ArrayType::get(Int8PtrTy, TypeInfos.size());
1406LPadInst-&gt;addClause(ConstantArray::get(FilterTy, TypeInfos));
1407</pre>
1408</div>
1409
1410<p>Converting from using the <code>@llvm.eh.resume</code> intrinsic to
1411 the <code>resume</code> instruction is trivial. It takes the exception
1412 pointer and exception selector values returned by
1413 the <code>landingpad</code> instruction:</p>
1414
1415<div class="doc_code">
1416<pre>
1417Type *UnwindDataTy = StructType::get(Builder.getInt8PtrTy(),
1418 Builder.getInt32Ty(), NULL);
1419Value *UnwindData = UndefValue::get(UnwindDataTy);
1420Value *ExcPtr = Builder.CreateLoad(getExceptionObjSlot());
1421Value *ExcSel = Builder.CreateLoad(getExceptionSelSlot());
1422UnwindData = Builder.CreateInsertValue(UnwindData, ExcPtr, 0, "exc_ptr");
1423UnwindData = Builder.CreateInsertValue(UnwindData, ExcSel, 1, "exc_sel");
1424Builder.CreateResume(UnwindData);
1425</pre>
1426</div>
1427
1428
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]1429
1430
Chris Lattner1c80fbf2011-11-27 20:51:47 +0000[diff] [blame]1431 -->
1432
Michael J. Spencer60f790c2011-11-28 18:20:09 +0000[diff] [blame^]1433
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]1434<!-- *********************************************************************** -->
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]1435
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1436<hr>
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]1437<address>
Misha Brukman38847d52003-12-21 22:53:21 +0000[diff] [blame]1438 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman44408702008-12-11 17:34:48 +0000[diff] [blame]1439 src="http://jigsaw.w3.org/css-validator/images/vcss-blue" alt="Valid CSS"></a>
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]1440 <a href="http://validator.w3.org/check/referer"><img
Misha Brukman44408702008-12-11 17:34:48 +0000[diff] [blame]1441 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]1442
Chris Lattnerb4b0ce72007-05-18 00:44:29 +0000[diff] [blame]1443 <a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1444 Last modified: $Date$
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]1445</address>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]1446
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1447</body>
1448</html>