blob: f62466c1d7d1279ae7454e564528d7d6fe25e9eb [file] [log] [blame]
Misha Brukman500bc302003-11-22 00:38:41 +00001<!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 +00005 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
Misha Brukman500bc302003-11-22 00:38:41 +00006 <link rel="stylesheet" href="llvm.css" type="text/css">
Chad Rosiere6291d02011-05-27 22:50:46 +00007 <title>LLVM 3.0 Release Notes</title>
Misha Brukman500bc302003-11-22 00:38:41 +00008</head>
9<body>
Chris Lattner79c3fe12003-10-02 04:57:28 +000010
Chad Rosiere6291d02011-05-27 22:50:46 +000011<h1>LLVM 3.0 Release Notes</h1>
Mikhail Glushenkovea65d7d2008-10-13 02:08:34 +000012
Chris Lattner0e464a92010-03-17 04:02:39 +000013<img align=right src="http://llvm.org/img/DragonSmall.png"
Gabor Greifee2187a2010-04-22 10:21:43 +000014 width="136" height="136" alt="LLVM Dragon Logo">
Chris Lattner0e464a92010-03-17 04:02:39 +000015
Chris Lattner79c3fe12003-10-02 04:57:28 +000016<ol>
Misha Brukman500bc302003-11-22 00:38:41 +000017 <li><a href="#intro">Introduction</a></li>
Chris Lattner96a445e2008-10-13 18:01:01 +000018 <li><a href="#subproj">Sub-project Status Update</a></li>
Chad Rosiere6291d02011-05-27 22:50:46 +000019 <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 +000021 <li><a href="GettingStarted.html">Installation Instructions</a></li>
Dan Gohman44aa9212008-10-14 16:23:02 +000022 <li><a href="#knownproblems">Known Problems</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +000023 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +000024</ol>
25
Chris Lattner7911ce22004-05-23 21:07:27 +000026<div class="doc_author">
NAKAMURA Takumib9a33632011-04-09 02:13:37 +000027 <p>Written by the <a href="http://llvm.org/">LLVM Team</a></p>
Misha Brukman500bc302003-11-22 00:38:41 +000028</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +000029
Chris Lattner49123fd2011-04-06 06:29:50 +000030<!--
Chad Rosiere6291d02011-05-27 22:50:46 +000031<h1 style="color:red">These are in-progress notes for the upcoming LLVM 3.0
Jeffrey Yasskinbec48772010-01-28 01:14:43 +000032release.<br>
33You may prefer the
Chad Rosiere6291d02011-05-27 22:50:46 +000034<a href="http://llvm.org/releases/2.9/docs/ReleaseNotes.html">LLVM 2.9
Dan Gohmanb44f6c62010-05-03 23:51:05 +000035Release Notes</a>.</h1>
Chris Lattner49123fd2011-04-06 06:29:50 +000036 -->
Jeffrey Yasskinbec48772010-01-28 01:14:43 +000037
Chris Lattner79c3fe12003-10-02 04:57:28 +000038<!-- *********************************************************************** -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +000039<h2>
Misha Brukman500bc302003-11-22 00:38:41 +000040 <a name="intro">Introduction</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +000041</h2>
Chris Lattner79c3fe12003-10-02 04:57:28 +000042<!-- *********************************************************************** -->
43
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +000044<div>
Misha Brukman500bc302003-11-22 00:38:41 +000045
Chris Lattnerf6662f92008-10-13 17:57:36 +000046<p>This document contains the release notes for the LLVM Compiler
Bill Wendling7b7fa742011-10-26 18:46:16 +000047 Infrastructure, release 3.0. Here we describe the status of LLVM, including
48 major improvements from the previous release and significant known problems.
49 All LLVM releases may be downloaded from
50 the <a href="http://llvm.org/releases/">LLVM releases web site</a>.</p>
Chris Lattner19092612003-10-02 16:38:05 +000051
Chris Lattner7506b1d2004-12-07 08:04:13 +000052<p>For more information about LLVM, including information about the latest
Bill Wendling7b7fa742011-10-26 18:46:16 +000053 release, please check out the <a href="http://llvm.org/">main LLVM web
54 site</a>. If you have questions or comments,
55 the <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM
56 Developer's Mailing List</a> is a good place to send them.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +000057
Bill Wendling7b7fa742011-10-26 18:46:16 +000058<p>Note that if you are reading this file from a Subversion checkout or the main
59 LLVM web page, this document applies to the <i>next</i> release, not the
60 current one. To see the release notes for a specific release, please see the
61 <a href="http://llvm.org/releases/">releases page</a>.</p>
Misha Brukman500bc302003-11-22 00:38:41 +000062
63</div>
Chris Lattner61358ab2009-10-13 17:48:04 +000064
Chris Lattnere4dc1962011-04-05 23:22:33 +000065<!-- Features that need text if they're finished for 3.1:
66 ARM EHABI
Chris Lattner914ce462010-04-22 06:28:20 +000067 combiner-aa?
Chris Lattner61358ab2009-10-13 17:48:04 +000068 strong phi elim
Chris Lattner61358ab2009-10-13 17:48:04 +000069 loop dependence analysis
Chris Lattnere07043c2010-09-29 05:30:03 +000070 CorrelatedValuePropagation
Chris Lattnere4dc1962011-04-05 23:22:33 +000071 lib/Transforms/IPO/MergeFunctions.cpp => consider for 3.1.
Chris Lattneracce85d2008-02-10 07:46:44 +000072 -->
Chris Lattnere07043c2010-09-29 05:30:03 +000073
Chris Lattner96a445e2008-10-13 18:01:01 +000074<!-- *********************************************************************** -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +000075<h2>
Chris Lattner96a445e2008-10-13 18:01:01 +000076 <a name="subproj">Sub-project Status Update</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +000077</h2>
Chris Lattner96a445e2008-10-13 18:01:01 +000078<!-- *********************************************************************** -->
Chris Lattnerea34f642008-06-08 21:34:41 +000079
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +000080<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +000081
82<p>The LLVM 3.0 distribution currently consists of code from the core LLVM
83 repository (which roughly includes the LLVM optimizers, code generators and
Chris Lattnerc343e312011-11-10 20:15:40 +000084 supporting tools), and the Clang repository. In
Bill Wendling7b7fa742011-10-26 18:46:16 +000085 addition to this code, the LLVM Project includes other sub-projects that are
86 in development. Here we include updates on these subprojects.</p>
Chris Lattner96a445e2008-10-13 18:01:01 +000087
Chris Lattner8348b472008-06-08 21:58:17 +000088<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +000089<h3>
Chris Lattnerfb97b2d2008-10-13 18:11:54 +000090<a name="clang">Clang: C/C++/Objective-C Frontend Toolkit</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +000091</h3>
Chris Lattner8348b472008-06-08 21:58:17 +000092
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +000093<div>
Chris Lattner8348b472008-06-08 21:58:17 +000094
Chris Lattner095539f2010-04-26 17:42:18 +000095<p><a href="http://clang.llvm.org/">Clang</a> is an LLVM front end for the C,
Bill Wendling7b7fa742011-10-26 18:46:16 +000096 C++, and Objective-C languages. Clang aims to provide a better user
97 experience through expressive diagnostics, a high level of conformance to
98 language standards, fast compilation, and low memory use. Like LLVM, Clang
99 provides a modular, library-based architecture that makes it suitable for
100 creating or integrating with other development tools. Clang is considered a
101 production-quality compiler for C, Objective-C, C++ and Objective-C++ on x86
102 (32- and 64-bit), and for darwin/arm targets.</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000103
Chad Rosiere6291d02011-05-27 22:50:46 +0000104<p>In the LLVM 3.0 time-frame, the Clang team has made many improvements:</p>
Douglas Gregorba087df2011-10-15 00:48:01 +0000105
106<ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000107 <li>Greatly improved support for building C++ applications, with greater
108 stability and better diagnostics.</li>
Douglas Gregorba087df2011-10-15 00:48:01 +0000109
Bill Wendling7b7fa742011-10-26 18:46:16 +0000110 <li><a href="http://clang.llvm.org/cxx_status.html">Improved support</a> for
111 the <a href="http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=50372">C++
112 2011</a> standard, including implementations of non-static data member
113 initializers, alias templates, delegating constructors, the range-based
114 for loop, and implicitly-generated move constructors and move assignment
115 operators, among others.</li>
Douglas Gregorba087df2011-10-15 00:48:01 +0000116
Bill Wendling7b7fa742011-10-26 18:46:16 +0000117 <li>Implemented support for some features of the upcoming C1x standard,
118 including static assertions and generic selections.</li>
Douglas Gregorba087df2011-10-15 00:48:01 +0000119
Bill Wendling7b7fa742011-10-26 18:46:16 +0000120 <li>Better detection of include and linking paths for system headers and
121 libraries, especially for Linux distributions.</li>
Douglas Gregorba087df2011-10-15 00:48:01 +0000122
Bill Wendling7b7fa742011-10-26 18:46:16 +0000123 <li>Implemented support
124 for <a href="http://clang.llvm.org/docs/AutomaticReferenceCounting.html">Automatic
125 Reference Counting</a> for Objective-C.</li>
Douglas Gregorba087df2011-10-15 00:48:01 +0000126
Bill Wendling7b7fa742011-10-26 18:46:16 +0000127 <li>Implemented a number of optimizations in <tt>libclang</tt>, the Clang C
128 interface, to improve the performance of code completion and the mapping
129 from source locations to abstract syntax tree nodes.</li>
Douglas Gregorba087df2011-10-15 00:48:01 +0000130</ul>
131
Chris Lattner0a6f6d52011-04-05 07:19:28 +0000132
Duncan Sandsf3ba7af2011-04-06 08:07:40 +0000133<p>If Clang rejects your code but another compiler accepts it, please take a
Bill Wendling7b7fa742011-10-26 18:46:16 +0000134 look at the <a href="http://clang.llvm.org/compatibility.html">language
135 compatibility</a> guide to make sure this is not intentional or a known
136 issue.</p>
Bill Wendling741748a2008-10-27 09:27:33 +0000137
Chris Lattnerfb97b2d2008-10-13 18:11:54 +0000138</div>
139
140<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000141<h3>
Duncan Sands528a5102011-04-04 11:09:08 +0000142<a name="dragonegg">DragonEgg: GCC front-ends, LLVM back-end</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000143</h3>
Chris Lattner61358ab2009-10-13 17:48:04 +0000144
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000145<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000146<p><a href="http://dragonegg.llvm.org/">DragonEgg</a> is a
147 <a href="http://gcc.gnu.org/wiki/plugins">gcc plugin</a> that replaces GCC's
Duncan Sands77352c92011-11-10 18:44:29 +0000148 optimizers and code generators with LLVM's. It works with gcc-4.5 or gcc-4.6,
149 targets the x86-32 and x86-64 processor families, and has been successfully
150 used on the Darwin, FreeBSD, KFreeBSD, Linux and OpenBSD platforms. It fully
151 supports Ada, C, C++ and Fortran. It has partial support for Go, Java, Obj-C
152 and Obj-C++.</p>
Duncan Sands749fd832010-04-02 09:23:15 +0000153
Bill Wendling7b7fa742011-10-26 18:46:16 +0000154<p>The 3.0 release has the following notable changes:</p>
155
Duncan Sands77352c92011-11-10 18:44:29 +0000156 <li>GCC version 4.6 is now fully supported.</li>
157
158 <li>Patching and building GCC is no longer required: the plugin should work
159 with your system GCC (version 4.5 or 4.6; on Debian/Ubuntu systems the
160 gcc-4.5-plugin-dev or gcc-4.6-plugin-dev package is also needed).</li>
161
162 <li>The <tt>-fplugin-arg-dragonegg-enable-gcc-optzns</tt> option, which runs
163 GCC's optimizers as well as LLVM's, now works much better. This is the
164 option to use if you want ultimate performance! It not yet completely
165 stable: it may cause the plugin to crash.</li>
166
167 <li>The type and constant conversion logic has been almost entirely rewritten,
168 fixing a multitude of obscure bugs.</li>
169
Duncan Sands4b1da2b2010-09-30 17:37:34 +0000170<ul>
Chad Rosiere6291d02011-05-27 22:50:46 +0000171<!--
172<li></li>
173-->
Duncan Sands4b1da2b2010-09-30 17:37:34 +0000174</ul>
Chris Lattner61358ab2009-10-13 17:48:04 +0000175
176</div>
177
Chris Lattner75547712010-10-03 23:49:06 +0000178<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000179<h3>
Chris Lattner75547712010-10-03 23:49:06 +0000180<a name="compiler-rt">compiler-rt: Compiler Runtime Library</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000181</h3>
Chris Lattner75547712010-10-03 23:49:06 +0000182
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000183<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000184
185<p>The new LLVM <a href="http://compiler-rt.llvm.org/">compiler-rt project</a>
186 is a simple library that provides an implementation of the low-level
187 target-specific hooks required by code generation and other runtime
188 components. For example, when compiling for a 32-bit target, converting a
189 double to a 64-bit unsigned integer is compiled into a runtime call to the
190 "__fixunsdfdi" function. The compiler-rt library provides highly optimized
191 implementations of this and other low-level routines (some are 3x faster than
192 the equivalent libgcc routines).</p>
Chris Lattner75547712010-10-03 23:49:06 +0000193
Chad Rosiere6291d02011-05-27 22:50:46 +0000194<p>In the LLVM 3.0 timeframe,</p>
Chris Lattner75547712010-10-03 23:49:06 +0000195
196</div>
Chris Lattner61358ab2009-10-13 17:48:04 +0000197
198<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000199<h3>
Chris Lattnere07043c2010-09-29 05:30:03 +0000200<a name="lldb">LLDB: Low Level Debugger</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000201</h3>
Chris Lattnere07043c2010-09-29 05:30:03 +0000202
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000203<div>
Chris Lattnere07043c2010-09-29 05:30:03 +0000204
Bill Wendling7b7fa742011-10-26 18:46:16 +0000205<p>LLDB has advanced by leaps and bounds in the 3.0 timeframe. It is
206 dramatically more stable and useful, and includes both a
207 new <a href="http://lldb.llvm.org/tutorial.html">tutorial</a> and
208 a <a href="http://lldb.llvm.org/lldb-gdb.html">side-by-side comparison with
209 GDB</a>.</p>
Chris Lattnere07043c2010-09-29 05:30:03 +0000210
211</div>
212
213<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000214<h3>
Chris Lattnere07043c2010-09-29 05:30:03 +0000215<a name="libc++">libc++: C++ Standard Library</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000216</h3>
Chris Lattnere07043c2010-09-29 05:30:03 +0000217
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000218<div>
Chris Lattnere07043c2010-09-29 05:30:03 +0000219
Bill Wendling7b7fa742011-10-26 18:46:16 +0000220<p>Like compiler_rt, libc++ is now <a href="DeveloperPolicy.html#license">dual
221 licensed</a> under the MIT and UIUC license, allowing it to be used more
222 permissively.</p>
Chris Lattnere07043c2010-09-29 05:30:03 +0000223
224</div>
225
Chris Lattner61358ab2009-10-13 17:48:04 +0000226
Chris Lattner3d6a80a2011-04-07 03:08:22 +0000227<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000228<h3>
Chris Lattner3d6a80a2011-04-07 03:08:22 +0000229<a name="LLBrowse">LLBrowse: IR Browser</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000230</h3>
Daniel Dunbar97b01a82010-10-04 17:39:47 +0000231
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000232<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000233
234<p><a href="http://llvm.org/svn/llvm-project/llbrowse/trunk/doc/LLBrowse.html">
235 LLBrowse</a> is an interactive viewer for LLVM modules. It can load any LLVM
236 module and displays its contents as an expandable tree view, facilitating an
237 easy way to inspect types, functions, global variables, or metadata nodes. It
238 is fully cross-platform, being based on the popular wxWidgets GUI
239 toolkit.</p>
240
Chris Lattner3d6a80a2011-04-07 03:08:22 +0000241</div>
242
243<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000244<h3>
Chris Lattner3d6a80a2011-04-07 03:08:22 +0000245<a name="vmkit">VMKit</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000246</h3>
Chris Lattner3d6a80a2011-04-07 03:08:22 +0000247
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000248<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000249
Chris Lattner3d6a80a2011-04-07 03:08:22 +0000250<p>The <a href="http://vmkit.llvm.org/">VMKit project</a> is an implementation
Bill Wendling7b7fa742011-10-26 18:46:16 +0000251 of a Java Virtual Machine (Java VM or JVM) that uses LLVM for static and
252 just-in-time compilation. As of LLVM 3.0, VMKit now supports generational
253 garbage collectors. The garbage collectors are provided by the MMTk
254 framework, and VMKit can be configured to use one of the numerous implemented
255 collectors of MMTk.</p>
256
Chris Lattner3d6a80a2011-04-07 03:08:22 +0000257</div>
258
259
Daniel Dunbar97b01a82010-10-04 17:39:47 +0000260<!--=========================================================================-->
Chris Lattner7a8e6c52011-04-05 18:38:45 +0000261<!--
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000262<h3>
Daniel Dunbar97b01a82010-10-04 17:39:47 +0000263<a name="klee">KLEE: A Symbolic Execution Virtual Machine</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000264</h3>
Daniel Dunbar97b01a82010-10-04 17:39:47 +0000265
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000266<div>
Daniel Dunbar97b01a82010-10-04 17:39:47 +0000267<p>
268<a href="http://klee.llvm.org/">KLEE</a> is a symbolic execution framework for
269programs in LLVM bitcode form. KLEE tries to symbolically evaluate "all" paths
270through the application and records state transitions that lead to fault
271states. This allows it to construct testcases that lead to faults and can even
272be used to verify some algorithms.
273</p>
274
Chris Lattnerbe2e1b52011-03-10 07:43:44 +0000275<p>UPDATE!</p>
Chris Lattner7a8e6c52011-04-05 18:38:45 +0000276</div>-->
Daniel Dunbar97b01a82010-10-04 17:39:47 +0000277
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000278</div>
Daniel Dunbar97b01a82010-10-04 17:39:47 +0000279
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000280<!-- *********************************************************************** -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000281<h2>
Chad Rosiere6291d02011-05-27 22:50:46 +0000282 <a name="externalproj">External Open Source Projects Using LLVM 3.0</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000283</h2>
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000284<!-- *********************************************************************** -->
285
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000286<div>
Chris Lattner61358ab2009-10-13 17:48:04 +0000287
288<p>An exciting aspect of LLVM is that it is used as an enabling technology for
289 a lot of other language and tools projects. This section lists some of the
Chad Rosiere6291d02011-05-27 22:50:46 +0000290 projects that have already been updated to work with LLVM 3.0.</p>
Chris Lattner75547712010-10-03 23:49:06 +0000291
Chris Lattner3bfe57e2011-04-06 01:13:49 +0000292<!--=========================================================================-->
Bill Wendling7be6bc52011-10-26 00:17:54 +0000293<h3>AddressSanitizer</h3>
294
295<div>
296
297<p><a href="http://code.google.com/p/address-sanitizer/">AddressSanitizer</a>
298 uses compiler instrumentation and a specialized malloc library to find C/C++
299 bugs such as use-after-free and out-of-bound accesses to heap, stack, and
300 globals. The key feature of the tool is speed: the average slowdown
301 introduced by AddressSanitizer is less than 2x.</p>
302
303</div>
304
305<!--=========================================================================-->
Bill Wendling29817ea2011-10-26 00:14:36 +0000306<h3>ClamAV</h3>
307
308<div>
Bill Wendlingf2a78332011-10-25 01:01:42 +0000309
Bill Wendling29817ea2011-10-26 00:14:36 +0000310<p><a href="http://www.clamav.net">Clam AntiVirus</a> is an open source (GPL)
311 anti-virus toolkit for UNIX, designed especially for e-mail scanning on mail
312 gateways.</p>
313
314<p>Since version 0.96 it
315 has <a href="http://vrt-sourcefire.blogspot.com/2010/09/introduction-to-clamavs-low-level.html">bytecode
316 signatures</a> that allow writing detections for complex malware.</p>
317
318<p>It uses LLVM's JIT to speed up the execution of bytecode on X86, X86-64,
319 PPC32/64, falling back to its own interpreter otherwise. The git version was
320 updated to work with LLVM 3.0.</p>
321
322</div>
323
324<!--=========================================================================-->
Bill Wendling65d1f412011-10-26 18:23:06 +0000325<h3>clReflect</h3>
326
327<div>
328
329<p><a href="https://bitbucket.org/dwilliamson/clreflect">clReflect</a> is a C++
330 parser that uses clang/LLVM to derive a light-weight reflection database
331 suitable for use in game development. It comes with a very simple runtime
332 library for loading and querying the database, requiring no external
333 dependencies (including CRT), and an additional utility library for object
334 management and serialisation.</p>
335
336</div>
337
338<!--=========================================================================-->
Bill Wendling63507d12011-10-29 01:10:01 +0000339<h3>Cling C++ Interpreter</h3>
340
341<div>
342
343<p><a href="http://cern.ch/cling">Cling</a> is an interactive compiler interface
344 (aka C++ interpreter). It uses LLVM's JIT and clang; it currently supports
345 C++ and C. It has a prompt interface, runs source files, calls into shared
346 libraries, prints the value of expressions, even does runtime lookup of
347 identifiers (dynamic scopes). And it just behaves like one would expect from
348 an interpreter.</p>
349
350</div>
351
352<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000353<h3>Crack Programming Language</h3>
Chris Lattner3bfe57e2011-04-06 01:13:49 +0000354
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000355<div>
Bill Wendling55d6e672011-11-03 20:10:01 +0000356
357<p><a href="http://code.google.com/p/crack-language/">Crack</a> aims to provide
358 the ease of development of a scripting language with the performance of a
359 compiled language. The language derives concepts from C++, Java and Python,
360 incorporating object-oriented programming, operator overloading and strong
361 typing.</p>
362
Chris Lattner3bfe57e2011-04-06 01:13:49 +0000363</div>
Chris Lattner3bfe57e2011-04-06 01:13:49 +0000364
365<!--=========================================================================-->
Bill Wendlingb99486f2011-11-08 05:22:54 +0000366<h3>Eero</h3>
367
368<div>
369
370<p><a href="http://eerolanguage.org/">Eero</a> is a fully
371 header-and-binary-compatible dialect of Objective-C 2.0, implemented with a
372 patched version of the Clang/LLVM compiler. It features a streamlined syntax,
373 Python-like indentation, and new operators, for improved readability and
374 reduced code clutter. It also has new features such as limited forms of
375 operator overloading and namespaces, and strict (type-and-operator-safe)
376 enumerations. It is inspired by languages such as Smalltalk, Python, and
377 Ruby.</p>
378
379</div>
380
381<!--=========================================================================-->
Bill Wendlingf9778192011-10-26 00:09:55 +0000382<h3>Glasgow Haskell Compiler (GHC)</h3>
383
384<div>
385
386<p>GHC is an open source, state-of-the-art programming suite for Haskell, a
387 standard lazy functional programming language. It includes an optimizing
388 static compiler generating good code for a variety of platforms, together
389 with an interactive system for convenient, quick development.</p>
390
391<p>GHC 7.0 and onwards include an LLVM code generator, supporting LLVM 2.8 and
392 later. Since LLVM 2.9, GHC now includes experimental support for the ARM
393 platform with LLVM 3.0.</p>
394
395</div>
396
397<!--=========================================================================-->
Bill Wendlingf62333d2011-10-25 20:35:31 +0000398<h3>gwXscript</h3>
399
400<div>
401
402<p><a href="http://botwars.tk/gwscript/">gwXscript</a> is an object oriented,
Bill Wendling7c38de22011-10-26 04:24:15 +0000403 aspect oriented programming language which can create both executables (ELF,
Bill Wendlingf62333d2011-10-25 20:35:31 +0000404 EXE) and shared libraries (DLL, SO, DYNLIB). The compiler is implemented in
405 its own language and translates scripts into LLVM-IR which can be optimized
406 and translated into native code by the LLVM framework. Source code in
407 gwScript contains definitions that expand the namespaces. So you can build
408 your project and simply 'plug out' features by removing a file. The remaining
409 project does not leave scars since you directly separate concerns by the
410 'template' feature of gwX. It is also possible to add new features to a
411 project by just adding files and without editing the original project. This
412 language is used for example to create games or content management systems
413 that should be extendable.</p>
414
415<p>gwXscript is strongly typed and offers comfort with its native types string,
416 hash and array. You can easily write new libraries in gwXscript or native
417 code. gwXscript is type safe and users should not be able to crash your
418 program or execute malicious code except code that is eating CPU time.</p>
419
420</div>
421
422<!--=========================================================================-->
Bill Wendling50cacc82011-10-26 22:55:18 +0000423<h3>include-what-you-use</h3>
424
425<div>
426
427<p><a href="http://code.google.com/p/include-what-you-use">include-what-you-use</a>
428 is a tool to ensure that a file directly <code>#include</code>s
429 all <code>.h</code> files that provide a symbol that the file uses. It also
430 removes superfluous <code>#include</code>s from source files.</p>
431
432</div>
433
434<!--=========================================================================-->
Bill Wendling32dc4d92011-11-07 22:05:17 +0000435<h3>ispc: The Intel SPMD Program Compiler</h3>
436
437<div>
438
439<p><a href="http://ispc.github.com">ispc</a> is a compiler for "single program,
440 multiple data" (SPMD) programs. It compiles a C-based SPMD programming
441 language to run on the SIMD units of CPUs; it often delivers 5-6x speedups on
442 a single core of a CPU with an 8-wide SIMD unit compared to serial code,
443 while still providing a clean and easy-to-understand programming model. For
444 an introduction to the language and its performance,
Chris Lattnerc343e312011-11-10 20:15:40 +0000445 see <a href="http://ispc.github.com/example.html">the walkthrough</a> of a short
Bill Wendling32dc4d92011-11-07 22:05:17 +0000446 example program. ispc is licensed under the BSD license.</p>
447
448</div>
449
450<!--=========================================================================-->
Bill Wendling57fd8762011-10-26 18:20:54 +0000451<h3>LanguageKit and Pragmatic Smalltalk</h3>
452
453<div>
454
455<p><a href="http://etoileos.com/etoile/features/languagekit/">LanguageKit</a> is
456 a framework for implementing dynamic languages sharing an object model with
457 Objective-C. It provides static and JIT compilation using LLVM along with
458 its own interpreter. Pragmatic Smalltalk is a dialect of Smalltalk, built on
459 top of LanguageKit, that interfaces directly with Objective-C, sharing the
460 same object representation and message sending behaviour. These projects are
461 developed as part of the &Eacute;toi&eacute; desktop environment.</p>
462
463</div>
464
465<!--=========================================================================-->
Bill Wendling03250532011-11-01 04:08:23 +0000466<h3>LuaAV</h3>
467
468<div>
469
470<p><a href="http://lua-av.mat.ucsb.edu/blog/">LuaAV</a> is a real-time
471 audiovisual scripting environment based around the Lua language and a
472 collection of libraries for sound, graphics, and other media protocols. LuaAV
473 uses LLVM and Clang to JIT compile efficient user-defined audio synthesis
474 routines specified in a declarative syntax.</p>
475
476</div>
477
478<!--=========================================================================-->
Bill Wendlingd4821b82011-10-26 00:16:17 +0000479<h3>Mono</h3>
480
481<div>
482
483<p>An open source, cross-platform implementation of C# and the CLR that is
484 binary compatible with Microsoft.NET. Has an optional, dynamically-loaded
485 LLVM code generation backend in Mini, the JIT compiler.</p>
486
487<p>Note that we use a Git mirror of LLVM with some patches. See:
488 https://github.com/mono/llvm</p>
489
490</div>
491
492<!--=========================================================================-->
Bill Wendlingba226272011-10-25 20:37:45 +0000493<h3>Portable OpenCL (pocl)</h3>
494
495<div>
496
497<p>Portable OpenCL is an open source implementation of the OpenCL standard which
498 can be easily adapted for new targets. One of the goals of the project is
499 improving performance portability of OpenCL programs, avoiding the need for
500 target-dependent manual optimizations. A "native" target is included, which
501 allows running OpenCL kernels on the host (CPU).</p>
502
503</div>
504
505<!--=========================================================================-->
Bill Wendling0bad98c2011-10-25 20:39:06 +0000506<h3>Pure</h3>
507
508<div>
509<p><a href="http://pure-lang.googlecode.com/">Pure</a> is an
510 algebraic/functional programming language based on term rewriting. Programs
511 are collections of equations which are used to evaluate expressions in a
512 symbolic fashion. The interpreter uses LLVM as a backend to JIT-compile Pure
513 programs to fast native code. Pure offers dynamic typing, eager and lazy
514 evaluation, lexical closures, a hygienic macro system (also based on term
515 rewriting), built-in list and matrix support (including list and matrix
516 comprehensions) and an easy-to-use interface to C and other programming
517 languages (including the ability to load LLVM bitcode modules, and inline C,
518 C++, Fortran and Faust code in Pure programs if the corresponding LLVM-enabled
519 compilers are installed).</p>
520
521<p>Pure version 0.48 has been tested and is known to work with LLVM 3.0
522 (and continues to work with older LLVM releases &gt;= 2.5).</p>
523
524</div>
525
526<!--=========================================================================-->
Bill Wendling537d85b2011-10-26 00:12:04 +0000527<h3>Renderscript</h3>
528
529<div>
530
531<p><a href="http://developer.android.com/guide/topics/renderscript/index.html">Renderscript</a>
532 is Android's advanced 3D graphics rendering and compute API. It provides a
533 portable C99-based language with extensions to facilitate common use cases
534 for enhancing graphics and thread level parallelism. The Renderscript
535 compiler frontend is based on Clang/LLVM. It emits a portable bitcode format
536 for the actual compiled script code, as well as reflects a Java interface for
537 developers to control the execution of the compiled bitcode. Executable
538 machine code is then generated from this bitcode by an LLVM backend on the
539 device. Renderscript is thus able to provide a mechanism by which Android
540 developers can improve performance of their applications while retaining
541 portability.</p>
542
543</div>
544
545<!--=========================================================================-->
Bill Wendling7d5b6212011-10-25 20:40:26 +0000546<h3>SAFECode</h3>
547
548<div>
549
550<p><a href="http://safecode.cs.illinois.edu">SAFECode</a> is a memory safe C/C++
551 compiler built using LLVM. It takes standard, unannotated C/C++ code,
552 analyzes the code to ensure that memory accesses and array indexing
553 operations are safe, and instruments the code with run-time checks when
554 safety cannot be proven statically. SAFECode can be used as a debugging aid
555 (like Valgrind) to find and repair memory safety bugs. It can also be used
556 to protect code from security attacks at run-time.</p>
557
558</div>
559
560<!--=========================================================================-->
Bill Wendling02b77b72011-10-26 07:38:19 +0000561<h3>The Stupid D Compiler (SDC)</h3>
562
563<div>
564
565<p><a href="https://github.com/bhelyer/SDC">The Stupid D Compiler</a> is a
566 project seeking to write a self-hosting compiler for the D programming
567 language without using the frontend of the reference compiler (DMD).</p>
568
569</div>
570
571<!--=========================================================================-->
Bill Wendling2d7b4af2011-10-25 20:24:32 +0000572<h3>TTA-based Co-design Environment (TCE)</h3>
573
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000574<div>
Bill Wendling2d7b4af2011-10-25 20:24:32 +0000575
Chris Lattner3bfe57e2011-04-06 01:13:49 +0000576<p>TCE is a toolset for designing application-specific processors (ASP) based on
Bill Wendling2d7b4af2011-10-25 20:24:32 +0000577 the Transport triggered architecture (TTA). The toolset provides a complete
578 co-design flow from C/C++ programs down to synthesizable VHDL and parallel
579 program binaries. Processor customization points include the register files,
580 function units, supported operations, and the interconnection network.</p>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000581
Chris Lattner3bfe57e2011-04-06 01:13:49 +0000582<p>TCE uses Clang and LLVM for C/C++ language support, target independent
Bill Wendling2d7b4af2011-10-25 20:24:32 +0000583 optimizations and also for parts of code generation. It generates new
Bill Wendling7b7fa742011-10-26 18:46:16 +0000584 LLVM-based code generators "on the fly" for the designed TTA processors and
585 loads them in to the compiler backend as runtime libraries to avoid
Bill Wendling2d7b4af2011-10-25 20:24:32 +0000586 per-target recompilation of larger parts of the compiler chain.</p>
Chris Lattner3bfe57e2011-04-06 01:13:49 +0000587
Bill Wendling7b7fa742011-10-26 18:46:16 +0000588</div>
Chris Lattner3bfe57e2011-04-06 01:13:49 +0000589
590<!--=========================================================================-->
Bill Wendling628c2662011-10-25 20:27:37 +0000591<h3>Tart Programming Language</h3>
592
593<div>
594
595<p><a href="http://code.google.com/p/tart/">Tart</a> is a general-purpose,
596 strongly typed programming language designed for application
597 developers. Strongly inspired by Python and C#, Tart focuses on practical
598 solutions for the professional software developer, while avoiding the clutter
599 and boilerplate of legacy languages like Java and C++. Although Tart is still
600 in development, the current implementation supports many features expected of
601 a modern programming language, such as garbage collection, powerful
602 bidirectional type inference, a greatly simplified syntax for template
603 metaprogramming, closures and function literals, reflection, operator
604 overloading, explicit mutability and immutability, and much more. Tart is
605 flexible enough to accommodate a broad range of programming styles and
606 philosophies, while maintaining a strong commitment to simplicity, minimalism
607 and elegance in design.</p>
608
609</div>
610
611<!--=========================================================================-->
Bill Wendling644ce532011-10-26 09:25:01 +0000612<h3>ThreadSanitizer</h3>
613
614<div>
615
616<p><a href="http://code.google.com/p/data-race-test/">ThreadSanitizer</a> is a
617 data race detector for (mostly) C and C++ code, available for Linux, Mac OS
618 and Windows. On different systems, we use binary instrumentation frameworks
Bill Wendlingae8538e2011-10-29 01:11:15 +0000619 (Valgrind and Pin) as frontends that generate the program events for the race
620 detection algorithm. On Linux, there's an option of using LLVM-based
621 compile-time instrumentation.</p>
Bill Wendling644ce532011-10-26 09:25:01 +0000622
623</div>
624
625<!--=========================================================================-->
Bill Wendling8a924c62011-10-26 07:42:45 +0000626<h3>The ZooLib C++ Cross-Platform Application Framework</h3>
627
628<div>
629
630<p><a href="http://www.zoolib.org/">ZooLib</a> is Open Source under the MIT
631 License. It provides GUI, filesystem access, TCP networking, thread-safe
632 memory management, threading and locking for Mac OS X, Classic Mac OS,
633 Microsoft Windows, POSIX operating systems with X11, BeOS, Haiku, Apple's iOS
634 and Research in Motion's BlackBerry.</p>
635
636<p>My current work is to use CLang's static analyzer to improve ZooLib's code
637 quality. I also plan to set up LLVM compiles of the demo programs and test
638 programs using CLang and LLVM on all the platforms that CLang, LLVM and
639 ZooLib all support.</p>
640
641</div>
Chris Lattnera844a3e2011-04-07 03:09:21 +0000642
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000643</div>
644
Chris Lattner8348b472008-06-08 21:58:17 +0000645<!-- *********************************************************************** -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000646<h2>
Chad Rosiere6291d02011-05-27 22:50:46 +0000647 <a name="whatsnew">What's New in LLVM 3.0?</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000648</h2>
Chris Lattner8348b472008-06-08 21:58:17 +0000649<!-- *********************************************************************** -->
650
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000651<div>
Chris Lattnerf8e0b4e2008-06-08 22:59:35 +0000652
Chris Lattner61358ab2009-10-13 17:48:04 +0000653<p>This release includes a huge number of bug fixes, performance tweaks and
Bill Wendling7b7fa742011-10-26 18:46:16 +0000654 minor improvements. Some of the major improvements and new features are
655 listed in this section.</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000656
Chris Lattner914ce462010-04-22 06:28:20 +0000657<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000658<h3>
Chris Lattner252b83d2008-02-06 18:00:06 +0000659<a name="majorfeatures">Major New Features</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000660</h3>
Chris Lattner252b83d2008-02-06 18:00:06 +0000661
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000662<div>
Chris Lattner252b83d2008-02-06 18:00:06 +0000663
Chris Lattnerc343e312011-11-10 20:15:40 +0000664<p><b>llvm-gcc is gone</b></p>
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000665
Chris Lattnerc343e312011-11-10 20:15:40 +0000666<p>LLVM 3.0 includes several major new capabilities:</p>
667
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000668<ul>
Chris Lattner1efe27e2011-04-06 00:45:11 +0000669
Chad Rosiere6291d02011-05-27 22:50:46 +0000670<!--
671<li></li>
672-->
Chris Lattner7a8e6c52011-04-05 18:38:45 +0000673
Chris Lattner8170c102008-02-10 08:18:42 +0000674</ul>
Chris Lattner0a6f6d52011-04-05 07:19:28 +0000675
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000676</div>
677
Chris Lattner84977642007-09-21 03:54:09 +0000678<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000679<h3>
Chris Lattner917cc712009-03-02 02:37:32 +0000680<a name="coreimprovements">LLVM IR and Core Improvements</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000681</h3>
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000682
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000683<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000684
Chris Lattner61358ab2009-10-13 17:48:04 +0000685<p>LLVM IR has several new features for better support of new targets and that
Bill Wendling7b7fa742011-10-26 18:46:16 +0000686 expose new optimization opportunities:</p>
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000687
Bill Wendlingbc5f6dd2011-10-26 18:33:01 +0000688<p>One of the biggest changes is that 3.0 has a new exception handling
689 system. The old system used LLVM intrinsics to convey the exception handling
690 information to the code generator. It worked in most cases, but not
691 all. Inlining was especially difficult to get right. Also, the intrinsics
692 could be moved away from the <code>invoke</code> instruction, making it hard
693 to recover that information.</p>
694
695<p>The new EH system makes exception handling a first-class member of the IR. It
696 adds two new instructions:</p>
697
Chris Lattner791f77b2008-06-05 06:25:56 +0000698<ul>
Bill Wendlingbc5f6dd2011-10-26 18:33:01 +0000699 <li><a href="LangRef.html#i_landingpad"><code>landingpad</code></a> &mdash;
700 this instruction defines a landing pad basic block. It contains all of the
701 information that's needed by the code generator. It's also required to be
702 the first non-PHI instruction in the landing pad. In addition, a landing
703 pad may be jumped to only by the unwind edge of an <code>invoke</code>
704 instruction.</li>
705
706 <li><a href="LangRef.html#i_resume"><code>resume</code></a> &mdash; this
707 instruction causes the current exception to resume traveling up the
708 stack. It replaces the <code>@llvm.eh.resume</code> intrinsic.</li>
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000709</ul>
Mikhail Glushenkovea65d7d2008-10-13 02:08:34 +0000710
Bill Wendlingbc5f6dd2011-10-26 18:33:01 +0000711<p>Converting from the old EH API to the new EH API is rather simple, because a
712 lot of complexity has been removed. The two intrinsics,
713 <code>@llvm.eh.exception</code> and <code>@llvm.eh.selector</code> have been
714 superceded by the <code>landingpad</code> instruction. Instead of generating
715 a call to <code>@llvm.eh.exception</code> and <code>@llvm.eh.selector</code>:
716
717<div class="doc_code">
718<pre>
719Function *ExcIntr = Intrinsic::getDeclaration(TheModule,
720 Intrinsic::eh_exception);
721Function *SlctrIntr = Intrinsic::getDeclaration(TheModule,
722 Intrinsic::eh_selector);
723
724// The exception pointer.
725Value *ExnPtr = Builder.CreateCall(ExcIntr, "exc_ptr");
726
727std::vector&lt;Value*&gt; Args;
728Args.push_back(ExnPtr);
729Args.push_back(Builder.CreateBitCast(Personality,
730 Type::getInt8PtrTy(Context)));
731
732<i>// Add selector clauses to Args.</i>
733
734// The selector call.
735Builder.CreateCall(SlctrIntr, Args, "exc_sel");
736</pre>
737</div>
738
739<p>You should instead generate a <code>landingpad</code> instruction, that
740 returns an exception object and selector value:</p>
741
742<div class="doc_code">
743<pre>
744LandingPadInst *LPadInst =
745 Builder.CreateLandingPad(StructType::get(Int8PtrTy, Int32Ty, NULL),
746 Personality, 0);
747
748Value *LPadExn = Builder.CreateExtractValue(LPadInst, 0);
749Builder.CreateStore(LPadExn, getExceptionSlot());
750
751Value *LPadSel = Builder.CreateExtractValue(LPadInst, 1);
752Builder.CreateStore(LPadSel, getEHSelectorSlot());
753</pre>
754</div>
755
756<p>It's now trivial to add the individual clauses to the <code>landingpad</code>
757 instruction.</p>
758
759<div class="doc_code">
760<pre>
761<i><b>// Adding a catch clause</b></i>
762Constant *TypeInfo = getTypeInfo();
763LPadInst-&gt;addClause(TypeInfo);
764
765<i><b>// Adding a C++ catch-all</b></i>
766LPadInst-&gt;addClause(Constant::getNullValue(Builder.getInt8PtrTy()));
767
768<i><b>// Adding a cleanup</b></i>
769LPadInst-&gt;setCleanup(true);
770
771<i><b>// Adding a filter clause</b></i>
772std::vector&lt;Constant*&gt; TypeInfos;
773Constant *TypeInfo = getFilterTypeInfo();
774TypeInfos.push_back(Builder.CreateBitCast(TypeInfo, Builder.getInt8PtrTy()));
775
776ArrayType *FilterTy = ArrayType::get(Int8PtrTy, TypeInfos.size());
777LPadInst-&gt;addClause(ConstantArray::get(FilterTy, TypeInfos));
778</pre>
779</div>
780
781<p>Converting from using the <code>@llvm.eh.resume</code> intrinsic to
782 the <code>resume</code> instruction is trivial. It takes the exception
783 pointer and exception selector values returned by
784 the <code>landingpad</code> instruction:</p>
785
786<div class="doc_code">
787<pre>
788Type *UnwindDataTy = StructType::get(Builder.getInt8PtrTy(),
789 Builder.getInt32Ty(), NULL);
790Value *UnwindData = UndefValue::get(UnwindDataTy);
791Value *ExcPtr = Builder.CreateLoad(getExceptionObjSlot());
792Value *ExcSel = Builder.CreateLoad(getExceptionSelSlot());
793UnwindData = Builder.CreateInsertValue(UnwindData, ExcPtr, 0, "exc_ptr");
794UnwindData = Builder.CreateInsertValue(UnwindData, ExcSel, 1, "exc_sel");
795Builder.CreateResume(UnwindData);
796</pre>
797</div>
798
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000799</div>
800
801<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000802<h3>
Andrew Trick5aab6382011-11-06 17:59:24 +0000803<a name="loopoptimization">Loop Optimization Improvements</a>
804</h3>
805
806<div>
807<p>The induction variable simplification pass in 3.0 only modifies
808 induction variables when profitable. Sign and zero extension
809 elimination, linear function test replacement, loop unrolling, and
810 other simplifications that require induction variable analysis have
811 been generalized so they no longer require loops to be rewritten in a
812 typically suboptimal form prior to optimization. This new design
813 preserves more IR level information, avoids undoing earlier loop
814 optimizations (particularly hand-optimized loops), and no longer
815 strongly depends on the code generator rewriting loops a second time
816 in a now optimal form--an intractable problem.</p>
817
818<p>The original behavior can be restored with -mllvm -enable-iv-rewrite;
819 however, support for this mode will be short lived. As such, bug
820 reports should be filed for any significant performance regressions
821 when moving from -mllvm -enable-iv-rewrite to the 3.0 default mode.</p>
822</div>
823
824<!--=========================================================================-->
825<h3>
Chris Lattneracce85d2008-02-10 07:46:44 +0000826<a name="optimizer">Optimizer Improvements</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000827</h3>
Chris Lattneracce85d2008-02-10 07:46:44 +0000828
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000829<div>
Chris Lattneracce85d2008-02-10 07:46:44 +0000830
Chris Lattner61358ab2009-10-13 17:48:04 +0000831<p>In addition to a large array of minor performance tweaks and bug fixes, this
Bill Wendling7b7fa742011-10-26 18:46:16 +0000832 release includes a few major enhancements and additions to the
833 optimizers:</p>
Chris Lattneracce85d2008-02-10 07:46:44 +0000834
835<ul>
Chad Rosiere6291d02011-05-27 22:50:46 +0000836<!--
837<li></li>
838-->
Chris Lattnerc5ac61d2011-04-06 05:50:04 +0000839</li>
Chris Lattner1efe27e2011-04-06 00:45:11 +0000840
Chris Lattner11b66112010-10-04 02:42:39 +0000841</ul>
842
Chris Lattner61358ab2009-10-13 17:48:04 +0000843</div>
Chris Lattner917cc712009-03-02 02:37:32 +0000844
Chris Lattner0b832202008-06-08 02:45:07 +0000845<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000846<h3>
Chris Lattner4ba2b652010-09-30 16:31:33 +0000847<a name="mc">MC Level Improvements</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000848</h3>
Chris Lattner4ba2b652010-09-30 16:31:33 +0000849
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000850<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000851
852<p>The LLVM Machine Code (aka MC) subsystem was created to solve a number of
853 problems in the realm of assembly, disassembly, object file format handling,
854 and a number of other related areas that CPU instruction-set level tools work
855 in.</p>
Chris Lattner7d9b6b42010-10-02 21:59:30 +0000856
Chris Lattner7d9b6b42010-10-02 21:59:30 +0000857<ul>
Chad Rosiere6291d02011-05-27 22:50:46 +0000858<!--
859<li></li>
860-->
Chris Lattner7d9b6b42010-10-02 21:59:30 +0000861</ul>
862
Bill Wendling7b7fa742011-10-26 18:46:16 +0000863<p>For more information, please see
864 the <a href="http://blog.llvm.org/2010/04/intro-to-llvm-mc-project.html">Intro
865 to the LLVM MC Project Blog Post</a>.</p>
Chris Lattner4ba2b652010-09-30 16:31:33 +0000866
NAKAMURA Takumi45c435a2011-04-05 08:24:22 +0000867</div>
Chris Lattner4ba2b652010-09-30 16:31:33 +0000868
Chris Lattner4ba2b652010-09-30 16:31:33 +0000869<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000870<h3>
Chris Lattner511433e2009-03-02 03:24:11 +0000871<a name="codegen">Target Independent Code Generator Improvements</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000872</h3>
Chris Lattner0b832202008-06-08 02:45:07 +0000873
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000874<div>
Chris Lattner0b832202008-06-08 02:45:07 +0000875
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000876<p>We have put a significant amount of work into the code generator
Bill Wendling7b7fa742011-10-26 18:46:16 +0000877 infrastructure, which allows us to implement more aggressive algorithms and
878 make it run faster:</p>
Chris Lattner0b832202008-06-08 02:45:07 +0000879
880<ul>
Chad Rosiere6291d02011-05-27 22:50:46 +0000881<!--
882<li></li>
883-->
Chris Lattner84977642007-09-21 03:54:09 +0000884</ul>
Chris Lattner84977642007-09-21 03:54:09 +0000885</div>
886
Chris Lattner917cc712009-03-02 02:37:32 +0000887<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000888<h3>
Chris Lattner917cc712009-03-02 02:37:32 +0000889<a name="x86">X86-32 and X86-64 Target Improvements</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000890</h3>
Chris Lattner917cc712009-03-02 02:37:32 +0000891
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000892<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000893
894<p>New features and major changes in the X86 target include:</p>
Chris Lattner917cc712009-03-02 02:37:32 +0000895
896<ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000897
898 <li>The CRC32 intrinsics have been renamed. The intrinsics were previously
899 <code>@llvm.x86.sse42.crc32.[8|16|32]</code>
900 and <code>@llvm.x86.sse42.crc64.[8|64]</code>. They have been renamed to
901 <code>@llvm.x86.sse42.crc32.32.[8|16|32]</code> and
902 <code>@llvm.x86.sse42.crc32.64.[8|64]</code>.</li>
Chad Rosierf94c9c12011-05-27 20:13:10 +0000903
Chris Lattner917cc712009-03-02 02:37:32 +0000904</ul>
905
Chris Lattner917cc712009-03-02 02:37:32 +0000906</div>
Chris Lattner84977642007-09-21 03:54:09 +0000907
908<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000909<h3>
Chris Lattner61358ab2009-10-13 17:48:04 +0000910<a name="ARM">ARM Target Improvements</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000911</h3>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000912
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000913<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000914
915<p>New features of the ARM target include:</p>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000916
917<ul>
Chad Rosiere6291d02011-05-27 22:50:46 +0000918<!--
919<li></li>
920-->
Bob Wilsone8472772010-09-13 17:39:35 +0000921</ul>
Chris Lattner61358ab2009-10-13 17:48:04 +0000922</div>
Chris Lattner1efe27e2011-04-06 00:45:11 +0000923
924<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000925<h3>
Chris Lattner1efe27e2011-04-06 00:45:11 +0000926<a name="OtherTS">Other Target Specific Improvements</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000927</h3>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000928
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000929<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000930
Chris Lattnerc343e312011-11-10 20:15:40 +0000931 <p>PPC32/ELF va_arg was implemented.</p>
932 <p>PPC32 initial support for .o file writing was implemented.</p>
933
Chris Lattner1efe27e2011-04-06 00:45:11 +0000934<ul>
Chad Rosiere6291d02011-05-27 22:50:46 +0000935<!--
936<li></li>
937-->
Chris Lattner1efe27e2011-04-06 00:45:11 +0000938</ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000939
Chris Lattner1efe27e2011-04-06 00:45:11 +0000940</div>
Chris Lattner77d29b12008-06-05 08:02:49 +0000941
942<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000943<h3>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000944<a name="changes">Major Changes and Removed Features</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000945</h3>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000946
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000947<div>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000948
Bill Wendling2626dba2011-08-03 22:18:20 +0000949<p>If you're already an LLVM user or developer with out-of-tree changes based on
950 LLVM 2.9, this section lists some "gotchas" that you may run into upgrading
951 from the previous release.</p>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000952
953<ul>
Eric Christopher90d6ec52011-09-28 19:47:28 +0000954 <li>The <code>LLVMC</code> front end code was removed while separating
955 out language independence.</li>
Jay Foadf42e9b22011-08-04 10:43:43 +0000956 <li>The <code>LowerSetJmp</code> pass wasn't used effectively by any
957 target and has been removed.</li>
Rafael Espindolaf940a1a2011-08-30 23:03:45 +0000958 <li>The old <code>TailDup</code> pass was not used in the standard pipeline
959 and was unable to update ssa form, so it has been removed.
Eli Friedmanf03bb262011-08-12 22:50:01 +0000960 <li>The syntax of volatile loads and stores in IR has been changed to
961 "<code>load volatile</code>"/"<code>store volatile</code>". The old
962 syntax ("<code>volatile load</code>"/"<code>volatile store</code>")
963 is still accepted, but is now considered deprecated.</li>
Eli Friedman526e1bb2011-10-26 00:55:23 +0000964 <li>The old atomic intrinscs (<code>llvm.memory.barrier</code> and
965 <code>llvm.atomic.*</code>) are now gone. Please use the new atomic
966 instructions, described in the <a href="Atomics.html">atomics guide</a>.
Devang Patelb34dd132008-10-14 20:03:43 +0000967</ul>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000968
NAKAMURA Takumi2026de22011-08-22 23:22:05 +0000969<h4>Windows (32-bit)</h4>
970<div>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000971
NAKAMURA Takumi2026de22011-08-22 23:22:05 +0000972<ul>
973 <li>On Win32(MinGW32 and MSVC), Windows 2000 will not be supported.
974 Windows XP or higher is required.</li>
975</ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000976
NAKAMURA Takumi2026de22011-08-22 23:22:05 +0000977</div>
978
Chris Lattnerf6662f92008-10-13 17:57:36 +0000979</div>
980
Daniel Dunbarf0233c62010-10-04 20:11:41 +0000981<!--=========================================================================-->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000982<h3>
Chris Lattner1efe27e2011-04-06 00:45:11 +0000983<a name="api_changes">Internal API Changes</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +0000984</h3>
Daniel Dunbarf0233c62010-10-04 20:11:41 +0000985
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +0000986<div>
Daniel Dunbarf0233c62010-10-04 20:11:41 +0000987
Chris Lattner1efe27e2011-04-06 00:45:11 +0000988<p>In addition, many APIs have changed in this release. Some of the major
Bill Wendling16005252011-08-02 06:20:17 +0000989 LLVM API changes are:</p>
Daniel Dunbarf0233c62010-10-04 20:11:41 +0000990
991<ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +0000992 <li>The biggest and most pervasive change is that llvm::Type's are no longer
993 returned or accepted as 'const' values. Instead, just pass around
994 non-const Type's.</li>
Chris Lattnerd1324302011-07-18 04:56:02 +0000995
Bill Wendling7b7fa742011-10-26 18:46:16 +0000996 <li><code>PHINode::reserveOperandSpace</code> has been removed. Instead, you
997 must specify how many operands to reserve space for when you create the
998 PHINode, by passing an extra argument
999 into <code>PHINode::Create</code>.</li>
Jay Foad558d3762011-07-14 09:19:05 +00001000
Bill Wendling7b7fa742011-10-26 18:46:16 +00001001 <li>PHINodes no longer store their incoming BasicBlocks as operands. Instead,
1002 the list of incoming BasicBlocks is stored separately, and can be accessed
1003 with new functions <code>PHINode::block_begin</code>
1004 and <code>PHINode::block_end</code>.</li>
Jay Foad558d3762011-07-14 09:19:05 +00001005
Bill Wendling7b7fa742011-10-26 18:46:16 +00001006 <li>Various functions now take an <code>ArrayRef</code> instead of either a
1007 pair of pointers (or iterators) to the beginning and end of a range, or a
1008 pointer and a length. Others now return an <code>ArrayRef</code> instead
1009 of a reference to a <code>SmallVector</code>
1010 or <code>std::vector</code>. These include:
Jay Foad558d3762011-07-14 09:19:05 +00001011<ul>
1012<!-- Please keep this list sorted. -->
Jay Foada3efbb12011-07-15 08:37:34 +00001013<li><code>CallInst::Create</code></li>
Jay Foad558d3762011-07-14 09:19:05 +00001014<li><code>ComputeLinearIndex</code> (in <code>llvm/CodeGen/Analysis.h</code>)</li>
1015<li><code>ConstantArray::get</code></li>
1016<li><code>ConstantExpr::getExtractElement</code></li>
Jay Foaddab3d292011-07-21 14:31:17 +00001017<li><code>ConstantExpr::getGetElementPtr</code></li>
1018<li><code>ConstantExpr::getInBoundsGetElementPtr</code></li>
Jay Foad558d3762011-07-14 09:19:05 +00001019<li><code>ConstantExpr::getIndices</code></li>
1020<li><code>ConstantExpr::getInsertElement</code></li>
1021<li><code>ConstantExpr::getWithOperands</code></li>
Jay Foad1d2f5692011-07-19 13:32:40 +00001022<li><code>ConstantFoldCall</code> (in <code>llvm/Analysis/ConstantFolding.h</code>)</li>
1023<li><code>ConstantFoldInstOperands</code> (in <code>llvm/Analysis/ConstantFolding.h</code>)</li>
Jay Foad558d3762011-07-14 09:19:05 +00001024<li><code>ConstantVector::get</code></li>
1025<li><code>DIBuilder::createComplexVariable</code></li>
1026<li><code>DIBuilder::getOrCreateArray</code></li>
1027<li><code>ExtractValueInst::Create</code></li>
1028<li><code>ExtractValueInst::getIndexedType</code></li>
1029<li><code>ExtractValueInst::getIndices</code></li>
1030<li><code>FindInsertedValue</code> (in <code>llvm/Analysis/ValueTracking.h</code>)</li>
Jay Foadca12a212011-07-19 14:42:50 +00001031<li><code>gep_type_begin</code> (in <code>llvm/Support/GetElementPtrTypeIterator.h</code>)</li>
1032<li><code>gep_type_end</code> (in <code>llvm/Support/GetElementPtrTypeIterator.h</code>)</li>
Jay Foada9203102011-07-25 09:48:08 +00001033<li><code>GetElementPtrInst::Create</code></li>
1034<li><code>GetElementPtrInst::CreateInBounds</code></li>
1035<li><code>GetElementPtrInst::getIndexedType</code></li>
Jay Foadb60e8512011-07-21 14:42:51 +00001036<li><code>InsertValueInst::Create</code></li>
1037<li><code>InsertValueInst::getIndices</code></li>
1038<li><code>InvokeInst::Create</code></li>
Jay Foada3efbb12011-07-15 08:37:34 +00001039<li><code>IRBuilder::CreateCall</code></li>
Jay Foad558d3762011-07-14 09:19:05 +00001040<li><code>IRBuilder::CreateExtractValue</code></li>
Jay Foad0a2a60a2011-07-22 08:16:57 +00001041<li><code>IRBuilder::CreateGEP</code></li>
1042<li><code>IRBuilder::CreateInBoundsGEP</code></li>
Jay Foad558d3762011-07-14 09:19:05 +00001043<li><code>IRBuilder::CreateInsertValue</code></li>
Jay Foada3efbb12011-07-15 08:37:34 +00001044<li><code>IRBuilder::CreateInvoke</code></li>
Jay Foad558d3762011-07-14 09:19:05 +00001045<li><code>MDNode::get</code></li>
1046<li><code>MDNode::getIfExists</code></li>
1047<li><code>MDNode::getTemporary</code></li>
1048<li><code>MDNode::getWhenValsUnresolved</code></li>
Jay Foadb9b54eb2011-07-19 15:07:52 +00001049<li><code>SimplifyGEPInst</code> (in <code>llvm/Analysis/InstructionSimplify.h</code>)</li>
Jay Foad8fbbb392011-07-19 14:01:37 +00001050<li><code>TargetData::getIndexedOffset</code></li>
Jay Foad558d3762011-07-14 09:19:05 +00001051</ul></li>
1052
Bill Wendling7b7fa742011-10-26 18:46:16 +00001053 <li>All forms of <code>StringMap::getOrCreateValue</code> have been remove
1054 except for the one which takes a <code>StringRef</code>.</li>
Jay Foad558d3762011-07-14 09:19:05 +00001055
Bill Wendling7b7fa742011-10-26 18:46:16 +00001056 <li>The <code>LLVMBuildUnwind</code> function from the C API was removed. The
1057 LLVM <code>unwind</code> instruction has been deprecated for a long time
1058 and isn't used by the current front-ends. So this was removed during the
1059 exception handling rewrite.</li>
Bill Wendling16005252011-08-02 06:20:17 +00001060
Bill Wendling7b7fa742011-10-26 18:46:16 +00001061 <li>The <code>LLVMAddLowerSetJmpPass</code> function from the C API was
1062 removed because the <code>LowerSetJmp</code> pass was removed.</li>
Bill Wendling2626dba2011-08-03 22:18:20 +00001063
Bill Wendling7b7fa742011-10-26 18:46:16 +00001064 <li>The <code>DIBuilder</code> interface used by front ends to encode
1065 debugging information in the LLVM IR now expects clients to
1066 use <code>DIBuilder::finalize()</code> at the end of translation unit to
1067 complete debugging information encoding.</li>
Devang Patel6326a422011-08-15 23:00:00 +00001068
Bill Wendling7b7fa742011-10-26 18:46:16 +00001069 <li>The way the type system works has been
1070 rewritten: <code>PATypeHolder</code> and <code>OpaqueType</code> are gone,
1071 and all APIs deal with <code>Type*</code> instead of <code>const
1072 Type*</code>. If you need to create recursive structures, then create a
1073 named structure, and use <code>setBody()</code> when all its elements are
1074 built. Type merging and refining is gone too: named structures are not
1075 merged with other structures, even if their layout is identical. (of
1076 course anonymous structures are still uniqued by layout).</li>
Torok Edwinf16e2d42011-09-30 13:07:52 +00001077
Bill Wendling7b7fa742011-10-26 18:46:16 +00001078 <li>TargetSelect.h moved to Support/ from Target/</li>
Torok Edwinf16e2d42011-09-30 13:07:52 +00001079
Bill Wendling7b7fa742011-10-26 18:46:16 +00001080 <li>UpgradeIntrinsicCall no longer upgrades pre-2.9 intrinsic calls (for
1081 example <code>llvm.memset.i32</code>).</li>
Torok Edwinf16e2d42011-09-30 13:07:52 +00001082
Bill Wendling7b7fa742011-10-26 18:46:16 +00001083 <li>It is mandatory to initialize all out-of-tree passes too and their dependencies now with
1084 <code>INITIALIZE_PASS{BEGIN,END,}</code>
1085 and <code>INITIALIZE_{PASS,AG}_DEPENDENCY</code>.</li>
Torok Edwinf16e2d42011-09-30 13:07:52 +00001086
Bill Wendling7b7fa742011-10-26 18:46:16 +00001087 <li>The interface for MemDepResult in MemoryDependenceAnalysis has been
1088 enhanced with new return types Unknown and NonFuncLocal, in addition to
1089 the existing types Clobber, Def, and NonLocal.</li>
Daniel Dunbarf0233c62010-10-04 20:11:41 +00001090</ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +00001091
Daniel Dunbarf0233c62010-10-04 20:11:41 +00001092</div>
Chris Lattnerf6662f92008-10-13 17:57:36 +00001093
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +00001094</div>
1095
Chris Lattner79c3fe12003-10-02 04:57:28 +00001096<!-- *********************************************************************** -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +00001097<h2>
Misha Brukman500bc302003-11-22 00:38:41 +00001098 <a name="knownproblems">Known Problems</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +00001099</h2>
Chris Lattner79c3fe12003-10-02 04:57:28 +00001100<!-- *********************************************************************** -->
1101
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +00001102<div>
Misha Brukman500bc302003-11-22 00:38:41 +00001103
Bill Wendling7b7fa742011-10-26 18:46:16 +00001104<p>This section contains significant known problems with the LLVM system, listed
1105 by component. If you run into a problem, please check
1106 the <a href="http://llvm.org/bugs/">LLVM bug database</a> and submit a bug if
1107 there isn't already one.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +00001108
Chris Lattnerf5ee1702004-03-14 02:03:02 +00001109<!-- ======================================================================= -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +00001110<h3>
Chris Lattnerf5ee1702004-03-14 02:03:02 +00001111 <a name="experimental">Experimental features included with this release</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +00001112</h3>
Chris Lattner79c3fe12003-10-02 04:57:28 +00001113
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +00001114<div>
Chris Lattnerf5ee1702004-03-14 02:03:02 +00001115
Misha Brukman6df9e2c2004-05-12 21:46:05 +00001116<p>The following components of this LLVM release are either untested, known to
Bill Wendling7b7fa742011-10-26 18:46:16 +00001117 be broken or unreliable, or are in early development. These components
1118 should not be relied on, and bugs should not be filed against them, but they
1119 may be useful to some people. In particular, if you would like to work on
1120 one of these components, please contact us on
1121 the <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev
1122 list</a>.</p>
Chris Lattnerf5ee1702004-03-14 02:03:02 +00001123
1124<ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +00001125 <li>The Alpha, Blackfin, CellSPU, MicroBlaze, MSP430, MIPS, PTX, SystemZ and
1126 XCore backends are experimental.</li>
1127
1128 <li><tt>llc</tt> "<tt>-filetype=obj</tt>" is experimental on all targets other
1129 than darwin and ELF X86 systems.</li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +00001130</ul>
1131
1132</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +00001133
Misha Brukman500bc302003-11-22 00:38:41 +00001134<!-- ======================================================================= -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +00001135<h3>
Chris Lattner26299222006-11-18 07:51:14 +00001136 <a name="x86-be">Known problems with the X86 back-end</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +00001137</h3>
John Criswellc0c186d2005-11-08 21:11:33 +00001138
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +00001139<div>
John Criswellc0c186d2005-11-08 21:11:33 +00001140
1141<ul>
Anton Korobeynikova6094be2008-06-08 10:24:13 +00001142 <li>The X86 backend does not yet support
Bill Wendling7b7fa742011-10-26 18:46:16 +00001143 all <a href="http://llvm.org/PR879">inline assembly that uses the X86
1144 floating point stack</a>. It supports the 'f' and 't' constraints, but
1145 not 'u'.</li>
1146
Dan Gohman8207ba92008-06-08 23:05:11 +00001147 <li>The X86-64 backend does not yet support the LLVM IR instruction
Bill Wendling7b7fa742011-10-26 18:46:16 +00001148 <tt>va_arg</tt>. Currently, front-ends support variadic argument
1149 constructs on X86-64 by lowering them manually.</li>
1150
NAKAMURA Takumi45c435a2011-04-05 08:24:22 +00001151 <li>Windows x64 (aka Win64) code generator has a few issues.
1152 <ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +00001153 <li>On mingw-w64, you will see unresolved symbol <tt>__chkstk</tt> due
1154 to <a href="http://llvm.org/bugs/show_bug.cgi?id=8919">Bug 8919</a>.
1155 It is fixed
1156 in <a href="http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20110321/118499.html">r128206</a>.</li>
1157
NAKAMURA Takumi45c435a2011-04-05 08:24:22 +00001158 <li>Miss-aligned MOVDQA might crash your program. It is due to
Bill Wendling7b7fa742011-10-26 18:46:16 +00001159 <a href="http://llvm.org/bugs/show_bug.cgi?id=9483">Bug 9483</a>, lack
1160 of handling aligned internal globals.</li>
NAKAMURA Takumi45c435a2011-04-05 08:24:22 +00001161 </ul>
1162 </li>
1163
Chris Lattner26299222006-11-18 07:51:14 +00001164</ul>
1165
1166</div>
1167
1168<!-- ======================================================================= -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +00001169<h3>
Chris Lattner26299222006-11-18 07:51:14 +00001170 <a name="ppc-be">Known problems with the PowerPC back-end</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +00001171</h3>
Chris Lattner26299222006-11-18 07:51:14 +00001172
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +00001173<div>
Chris Lattner26299222006-11-18 07:51:14 +00001174
1175<ul>
Roman Divacky223764c2011-10-30 07:49:04 +00001176 <li>The PPC32/ELF support lacks PIC support.</li>
Chris Lattner26299222006-11-18 07:51:14 +00001177</ul>
1178
1179</div>
1180
1181<!-- ======================================================================= -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +00001182<h3>
Chris Lattnerf3e5bc62007-05-14 06:56:09 +00001183 <a name="arm-be">Known problems with the ARM back-end</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +00001184</h3>
Chris Lattnerf3e5bc62007-05-14 06:56:09 +00001185
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +00001186<div>
Chris Lattnerf3e5bc62007-05-14 06:56:09 +00001187
1188<ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +00001189 <li>Thumb mode works only on ARMv6 or higher processors. On sub-ARMv6
1190 processors, thumb programs can crash or produce wrong results
1191 (<a href="http://llvm.org/PR1388">PR1388</a>).</li>
1192
1193 <li>Compilation for ARM Linux OABI (old ABI) is supported but not fully
1194 tested.</li>
Chris Lattnerf3e5bc62007-05-14 06:56:09 +00001195</ul>
1196
1197</div>
1198
1199<!-- ======================================================================= -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +00001200<h3>
Chris Lattner26299222006-11-18 07:51:14 +00001201 <a name="sparc-be">Known problems with the SPARC back-end</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +00001202</h3>
Chris Lattner26299222006-11-18 07:51:14 +00001203
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +00001204<div>
Chris Lattner26299222006-11-18 07:51:14 +00001205
1206<ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +00001207 <li>The SPARC backend only supports the 32-bit SPARC ABI (-m32); it does not
1208 support the 64-bit SPARC ABI (-m64).</li>
Chris Lattner26299222006-11-18 07:51:14 +00001209</ul>
1210
1211</div>
1212
1213<!-- ======================================================================= -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +00001214<h3>
Bruno Cardoso Lopesb7e1a4f2008-10-25 14:56:26 +00001215 <a name="mips-be">Known problems with the MIPS back-end</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +00001216</h3>
Bruno Cardoso Lopesb7e1a4f2008-10-25 14:56:26 +00001217
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +00001218<div>
Bruno Cardoso Lopesb7e1a4f2008-10-25 14:56:26 +00001219
1220<ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +00001221 <li>64-bit MIPS targets are not supported yet.</li>
Bruno Cardoso Lopesb7e1a4f2008-10-25 14:56:26 +00001222</ul>
1223
1224</div>
1225
1226<!-- ======================================================================= -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +00001227<h3>
Chris Lattner26299222006-11-18 07:51:14 +00001228 <a name="alpha-be">Known problems with the Alpha back-end</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +00001229</h3>
Chris Lattner26299222006-11-18 07:51:14 +00001230
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +00001231<div>
Chris Lattner26299222006-11-18 07:51:14 +00001232
1233<ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +00001234 <li>On 21164s, some rare FP arithmetic sequences which may trap do not have
1235 the appropriate nops inserted to ensure restartability.</li>
John Criswellc0c186d2005-11-08 21:11:33 +00001236</ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +00001237
John Criswellc0c186d2005-11-08 21:11:33 +00001238</div>
1239
Chris Lattner26299222006-11-18 07:51:14 +00001240<!-- ======================================================================= -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +00001241<h3>
Chris Lattnerf3e5bc62007-05-14 06:56:09 +00001242 <a name="c-be">Known problems with the C back-end</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +00001243</h3>
Chris Lattner26299222006-11-18 07:51:14 +00001244
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +00001245<div>
Chris Lattner26299222006-11-18 07:51:14 +00001246
Chris Lattner3016ee92010-09-29 05:34:42 +00001247<p>The C backend has numerous problems and is not being actively maintained.
Bill Wendling7b7fa742011-10-26 18:46:16 +00001248 Depending on it for anything serious is not advised.</p>
Chris Lattner3016ee92010-09-29 05:34:42 +00001249
Chris Lattner26299222006-11-18 07:51:14 +00001250<ul>
Bill Wendling7b7fa742011-10-26 18:46:16 +00001251 <li><a href="http://llvm.org/PR802">The C backend has only basic support for
1252 inline assembly code</a>.</li>
1253
1254 <li><a href="http://llvm.org/PR1658">The C backend violates the ABI of common
1255 C++ programs</a>, preventing intermixing between C++ compiled by the CBE
1256 and C++ code compiled with <tt>llc</tt> or native compilers.</li>
1257
1258 <li>The C backend does not support all exception handling constructs.</li>
1259
1260 <li>The C backend does not support arbitrary precision integers.</li>
Chris Lattner26299222006-11-18 07:51:14 +00001261</ul>
1262
1263</div>
John Criswellc0c186d2005-11-08 21:11:33 +00001264
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +00001265</div>
1266
Chris Lattner79c3fe12003-10-02 04:57:28 +00001267<!-- *********************************************************************** -->
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +00001268<h2>
Misha Brukman500bc302003-11-22 00:38:41 +00001269 <a name="additionalinfo">Additional Information</a>
NAKAMURA Takumi06c6d9a2011-04-18 01:17:51 +00001270</h2>
Chris Lattner79c3fe12003-10-02 04:57:28 +00001271<!-- *********************************************************************** -->
1272
NAKAMURA Takumi074eeaa2011-04-21 01:52:00 +00001273<div>
Misha Brukman500bc302003-11-22 00:38:41 +00001274
Bill Wendling7b7fa742011-10-26 18:46:16 +00001275<p>A wide variety of additional information is available on
1276 the <a href="http://llvm.org/">LLVM web page</a>, in particular in
1277 the <a href="http://llvm.org/docs/">documentation</a> section. The web page
1278 also contains versions of the API documentation which is up-to-date with the
1279 Subversion version of the source code. You can access versions of these
1280 documents specific to this release by going into the "<tt>llvm/doc/</tt>"
1281 directory in the LLVM tree.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +00001282
Misha Brukman500bc302003-11-22 00:38:41 +00001283<p>If you have any questions or comments about LLVM, please feel free to contact
Bill Wendling7b7fa742011-10-26 18:46:16 +00001284 us via the <a href="http://llvm.org/docs/#maillist"> mailing lists</a>.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +00001285
Misha Brukman500bc302003-11-22 00:38:41 +00001286</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +00001287
1288<!-- *********************************************************************** -->
Chris Lattner79c3fe12003-10-02 04:57:28 +00001289
Misha Brukman500bc302003-11-22 00:38:41 +00001290<hr>
Misha Brukman2061e892003-11-22 01:23:39 +00001291<address>
Misha Brukman38847d52003-12-21 22:53:21 +00001292 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman44408702008-12-11 17:34:48 +00001293 src="http://jigsaw.w3.org/css-validator/images/vcss-blue" alt="Valid CSS"></a>
Misha Brukman2061e892003-11-22 01:23:39 +00001294 <a href="http://validator.w3.org/check/referer"><img
Misha Brukman44408702008-12-11 17:34:48 +00001295 src="http://www.w3.org/Icons/valid-html401-blue" alt="Valid HTML 4.01"></a>
Misha Brukman2061e892003-11-22 01:23:39 +00001296
Chris Lattnerb4b0ce72007-05-18 00:44:29 +00001297 <a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br>
Misha Brukman500bc302003-11-22 00:38:41 +00001298 Last modified: $Date$
Misha Brukman2061e892003-11-22 01:23:39 +00001299</address>
Chris Lattner79c3fe12003-10-02 04:57:28 +00001300
Misha Brukman500bc302003-11-22 00:38:41 +00001301</body>
1302</html>