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gerrit-public.fairphone.software / fp2-dev / platform / external / llvm / 8a6e53e1162663dd2bc1da783fe2ff5947fba9e0 / . / docs / ReleaseNotes.html
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Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
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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">
Dan Gohmanb44f6c62010-05-03 23:51:05 +0000[diff] [blame]7 <title>LLVM 2.8 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
Dan Gohmanb44f6c62010-05-03 23:51:05 +0000[diff] [blame]11<div class="doc_title">LLVM 2.8 Release Notes</div>
Mikhail Glushenkovea65d7d2008-10-13 02:08:34 +0000[diff] [blame]12
Chris Lattner0e464a92010-03-17 04:02:39 +0000[diff] [blame]13<img align=right src="http://llvm.org/img/DragonSmall.png"
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>
Dan Gohmanb44f6c62010-05-03 23:51:05 +0000[diff] [blame]19 <li><a href="#externalproj">External Projects Using LLVM 2.8</a></li>
20 <li><a href="#whatsnew">What's New in LLVM 2.8?</a></li>
Chris Lattner4b538b92004-04-30 22:17:12 +0000[diff] [blame]21 <li><a href="GettingStarted.html">Installation Instructions</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]22 <li><a href="#portability">Portability and Supported Platforms</a></li>
Dan Gohman44aa9212008-10-14 16:23:02 +0000[diff] [blame]23 <li><a href="#knownproblems">Known Problems</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]24 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]25</ol>
26
Chris Lattner7911ce22004-05-23 21:07:27 +0000[diff] [blame]27<div class="doc_author">
Dan Gohman44aa9212008-10-14 16:23:02 +0000[diff] [blame]28 <p>Written by the <a href="http://llvm.org">LLVM Team</a></p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]29</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]30
Chris Lattner7b91eda2010-04-22 05:41:35 +0000[diff] [blame]31<h1 style="color:red">These are in-progress notes for the upcoming LLVM 2.8
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]32release.<br>
33You may prefer the
Dan Gohmanb44f6c62010-05-03 23:51:05 +0000[diff] [blame]34<a href="http://llvm.org/releases/2.7/docs/ReleaseNotes.html">LLVM 2.7
35Release Notes</a>.</h1>
Jeffrey Yasskinbec48772010-01-28 01:14:43 +0000[diff] [blame]36
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]37<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]38<div class="doc_section">
39 <a name="intro">Introduction</a>
40</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]41<!-- *********************************************************************** -->
42
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]43<div class="doc_text">
44
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]45<p>This document contains the release notes for the LLVM Compiler
Dan Gohman7ae3ac82010-05-03 23:52:21 +0000[diff] [blame]46Infrastructure, release 2.8. Here we describe the status of LLVM, including
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]47major improvements from the previous release and significant known problems.
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000[diff] [blame]48All LLVM releases may be downloaded from the <a
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]49href="http://llvm.org/releases/">LLVM releases web site</a>.</p>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]50
Chris Lattner7506b1d2004-12-07 08:04:13 +0000[diff] [blame]51<p>For more information about LLVM, including information about the latest
Chris Lattnerc463b272005-10-29 07:07:09 +0000[diff] [blame]52release, please check out the <a href="http://llvm.org/">main LLVM
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]53web site</a>. If you have questions or comments, the <a
Chris Lattnerc66bfef2010-03-17 04:41:49 +0000[diff] [blame]54href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM Developer's
55Mailing List</a> is a good place to send them.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]56
Mikhail Glushenkovea65d7d2008-10-13 02:08:34 +0000[diff] [blame]57<p>Note that if you are reading this file from a Subversion checkout or the
Chris Lattner84977642007-09-21 03:54:09 +0000[diff] [blame]58main LLVM web page, this document applies to the <i>next</i> release, not the
Gabor Greiffa933f82008-10-14 11:00:32 +0000[diff] [blame]59current one. To see the release notes for a specific release, please see the
Chris Lattner84977642007-09-21 03:54:09 +0000[diff] [blame]60<a href="http://llvm.org/releases/">releases page</a>.</p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]61
62</div>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]63
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]64
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]65<!--
66Almost dead code.
67 include/llvm/Analysis/LiveValues.h => Dan
68 lib/Transforms/IPO/MergeFunctions.cpp => consider for 2.8.
69 llvm/Analysis/PointerTracking.h => Edwin wants this, consider for 2.8.
Chris Lattner61c70e92010-08-28 04:09:24 +0000[diff] [blame]70 GEPSplitterPass
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]71-->
72
73
Dan Gohmanb44f6c62010-05-03 23:51:05 +0000[diff] [blame]74<!-- Features that need text if they're finished for 2.8:
Chris Lattner914ce462010-04-22 06:28:20 +0000[diff] [blame]75 combiner-aa?
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]76 strong phi elim
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]77 llvm.dbg.value: variable debug info for optimized code
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]78 loop dependence analysis
Chris Lattner885b6612010-08-28 16:33:36 +0000[diff] [blame]79 TBAA
Chris Lattneracce85d2008-02-10 07:46:44 +0000[diff] [blame]80 -->
Mikhail Glushenkovea65d7d2008-10-13 02:08:34 +0000[diff] [blame]81
Chris Lattner547a3912008-10-12 19:47:48 +0000[diff] [blame]82 <!-- for announcement email:
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]83 Logo web page.
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]84 Many new papers added to /pubs/
Chris Lattner74c80df2009-02-25 06:34:50 +0000[diff] [blame]85 -->
Chris Lattneracce85d2008-02-10 07:46:44 +0000[diff] [blame]86
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]87<!-- *********************************************************************** -->
88<div class="doc_section">
89 <a name="subproj">Sub-project Status Update</a>
Chris Lattnerea34f642008-06-08 21:34:41 +0000[diff] [blame]90</div>
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]91<!-- *********************************************************************** -->
Chris Lattnerea34f642008-06-08 21:34:41 +0000[diff] [blame]92
93<div class="doc_text">
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]94<p>
Dan Gohmanb44f6c62010-05-03 23:51:05 +0000[diff] [blame]95The LLVM 2.8 distribution currently consists of code from the core LLVM
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]96repository (which roughly includes the LLVM optimizers, code generators
97and supporting tools), the Clang repository and the llvm-gcc repository. In
98addition to this code, the LLVM Project includes other sub-projects that are in
99development. Here we include updates on these subprojects.
Bill Wendling63d8c552009-03-02 04:28:57 +0000[diff] [blame]100</p>
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]101
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]102</div>
103
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]104
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]105<!--=========================================================================-->
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]106<div class="doc_subsection">
Chris Lattnerfb97b2d2008-10-13 18:11:54 +0000[diff] [blame]107<a name="clang">Clang: C/C++/Objective-C Frontend Toolkit</a>
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]108</div>
109
110<div class="doc_text">
111
Chris Lattner095539f2010-04-26 17:42:18 +0000[diff] [blame]112<p><a href="http://clang.llvm.org/">Clang</a> is an LLVM front end for the C,
113C++, and Objective-C languages. Clang aims to provide a better user experience
114through expressive diagnostics, a high level of conformance to language
115standards, fast compilation, and low memory use. Like LLVM, Clang provides a
116modular, library-based architecture that makes it suitable for creating or
117integrating with other development tools. Clang is considered a
118production-quality compiler for C and Objective-C on x86 (32- and 64-bit).</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]119
Chris Lattner922d00f2010-07-21 15:57:40 +0000[diff] [blame]120<p>In the LLVM 2.8 time-frame, the Clang team has made many improvements:</p>
Bill Wendling741748a2008-10-27 09:27:33 +0000[diff] [blame]121
Daniel Dunbar13739432008-10-14 23:25:09 +0000[diff] [blame]122<ul>
David Chisnall8e0bd802010-04-25 19:13:33 +0000[diff] [blame]123
Bill Wendling6bc15282009-03-02 04:28:18 +0000[diff] [blame]124</ul>
Chris Lattnerfb97b2d2008-10-13 18:11:54 +0000[diff] [blame]125</div>
126
127<!--=========================================================================-->
128<div class="doc_subsection">
129<a name="clangsa">Clang Static Analyzer</a>
130</div>
131
132<div class="doc_text">
133
Chris Lattner8cdd7932010-04-22 06:38:11 +0000[diff] [blame]134<p>The <a href="http://clang-analyzer.llvm.org/">Clang Static Analyzer</a>
135 project is an effort to use static source code analysis techniques to
136 automatically find bugs in C and Objective-C programs (and hopefully <a
137 href="http://clang-analyzer.llvm.org/dev_cxx.html">C++ in the
138 future</a>!). The tool is very good at finding bugs that occur on specific
139 paths through code, such as on error conditions.</p>
Chris Lattnercc042612008-10-14 00:52:49 +0000[diff] [blame]140
Chris Lattner922d00f2010-07-21 15:57:40 +0000[diff] [blame]141<p>In the LLVM 2.8 time-frame,
Chris Lattner8cdd7932010-04-22 06:38:11 +0000[diff] [blame]142</p>
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]143
144</div>
145
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]146<!--=========================================================================-->
147<div class="doc_subsection">
Nicolas Geoffray99a4d302008-10-14 19:23:04 +0000[diff] [blame]148<a name="vmkit">VMKit: JVM/CLI Virtual Machine Implementation</a>
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]149</div>
150
151<div class="doc_text">
152<p>
Nicolas Geoffray99a4d302008-10-14 19:23:04 +0000[diff] [blame]153The <a href="http://vmkit.llvm.org/">VMKit project</a> is an implementation of
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]154a JVM and a CLI Virtual Machine (Microsoft .NET is an
155implementation of the CLI) using LLVM for static and just-in-time
156compilation.</p>
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]157
Chris Lattner922d00f2010-07-21 15:57:40 +0000[diff] [blame]158<p>With the release of LLVM 2.8, ...</p>
Chris Lattner96a445e2008-10-13 18:01:01 +0000[diff] [blame]159
160</div>
161
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]162
163<!--=========================================================================-->
164<div class="doc_subsection">
165<a name="compiler-rt">compiler-rt: Compiler Runtime Library</a>
166</div>
167
168<div class="doc_text">
169<p>
170The new LLVM <a href="http://compiler-rt.llvm.org/">compiler-rt project</a>
171is a simple library that provides an implementation of the low-level
172target-specific hooks required by code generation and other runtime components.
173For example, when compiling for a 32-bit target, converting a double to a 64-bit
174unsigned integer is compiled into a runtime call to the "__fixunsdfdi"
175function. The compiler-rt library provides highly optimized implementations of
176this and other low-level routines (some are 3x faster than the equivalent
177libgcc routines).</p>
178
179<p>
180All of the code in the compiler-rt project is available under the standard LLVM
Chris Lattner922d00f2010-07-21 15:57:40 +0000[diff] [blame]181License, a "BSD-style" license. New in LLVM 2.8:
182
183Soft float support
184</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]185
186</div>
187
188<!--=========================================================================-->
189<div class="doc_subsection">
Duncan Sands749fd832010-04-02 09:23:15 +0000[diff] [blame]190<a name="dragonegg">DragonEgg: llvm-gcc ported to gcc-4.5</a>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]191</div>
192
193<div class="doc_text">
194<p>
Duncan Sands749fd832010-04-02 09:23:15 +0000[diff] [blame]195<a href="http://dragonegg.llvm.org/">DragonEgg</a> is a port of llvm-gcc to
196gcc-4.5. Unlike llvm-gcc, which makes many intrusive changes to the underlying
197gcc-4.2 code, dragonegg in theory does not require any gcc-4.5 modifications
198whatsoever (currently one small patch is needed). This is thanks to the new
199<a href="http://gcc.gnu.org/wiki/plugins">gcc plugin architecture</a>, which
200makes it possible to modify the behaviour of gcc at runtime by loading a plugin,
201which is nothing more than a dynamic library which conforms to the gcc plugin
202interface. DragonEgg is a gcc plugin that causes the LLVM optimizers to be run
203instead of the gcc optimizers, and the LLVM code generators instead of the gcc
204code generators, just like llvm-gcc. To use it, you add
205"-fplugin=path/dragonegg.so" to the gcc-4.5 command line, and gcc-4.5 magically
206becomes llvm-gcc-4.5!
207</p>
208
209<p>
210DragonEgg is still a work in progress. Currently C works very well, while C++,
211Ada and Fortran work fairly well. All other languages either don't work at all,
212or only work poorly. For the moment only the x86-32 and x86-64 targets are
Duncan Sands51a51742010-04-20 19:40:58 +0000[diff] [blame]213supported, and only on linux and darwin (darwin needs an additional gcc patch).
Duncan Sands749fd832010-04-02 09:23:15 +0000[diff] [blame]214</p>
215
216<p>
Chris Lattner922d00f2010-07-21 15:57:40 +0000[diff] [blame]2172.8 status here.
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]218</p>
219
220</div>
221
222
223<!--=========================================================================-->
224<div class="doc_subsection">
225<a name="mc">llvm-mc: Machine Code Toolkit</a>
226</div>
227
228<div class="doc_text">
229<p>
Chris Lattner8cdd7932010-04-22 06:38:11 +0000[diff] [blame]230The LLVM Machine Code (aka MC) sub-project of LLVM was created to solve a number
231of problems in the realm of assembly, disassembly, object file format handling,
232and a number of other related areas that CPU instruction-set level tools work
233in. It is a sub-project of LLVM which provides it with a number of advantages
234over other compilers that do not have tightly integrated assembly-level tools.
235For a gentle introduction, please see the <a
236href="http://blog.llvm.org/2010/04/intro-to-llvm-mc-project.html">Intro to the
237LLVM MC Project Blog Post</a>.
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]238</p>
239
Chris Lattner922d00f2010-07-21 15:57:40 +0000[diff] [blame]240<p>2.8 status here</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]241</div>
242
243
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000[diff] [blame]244<!-- *********************************************************************** -->
245<div class="doc_section">
Chris Lattner922d00f2010-07-21 15:57:40 +0000[diff] [blame]246 <a name="externalproj">External Open Source Projects Using LLVM 2.8</a>
Chris Lattnerab68e9e2009-02-26 22:33:38 +0000[diff] [blame]247</div>
248<!-- *********************************************************************** -->
249
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]250<div class="doc_text">
251
252<p>An exciting aspect of LLVM is that it is used as an enabling technology for
253 a lot of other language and tools projects. This section lists some of the
Chris Lattner922d00f2010-07-21 15:57:40 +0000[diff] [blame]254 projects that have already been updated to work with LLVM 2.8.</p>
Chris Lattner7c8e7962010-04-26 17:38:10 +0000[diff] [blame]255</div>
256
Chris Lattner3a1d4cf2010-04-22 21:34:16 +0000[diff] [blame]257
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]258<!-- *********************************************************************** -->
259<div class="doc_section">
Chris Lattner922d00f2010-07-21 15:57:40 +0000[diff] [blame]260 <a name="whatsnew">What's New in LLVM 2.8?</a>
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]261</div>
262<!-- *********************************************************************** -->
263
Chris Lattnerf8e0b4e2008-06-08 22:59:35 +0000[diff] [blame]264<div class="doc_text">
265
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]266<p>This release includes a huge number of bug fixes, performance tweaks and
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]267minor improvements. Some of the major improvements and new features are listed
268in this section.
Chris Lattnerf8e0b4e2008-06-08 22:59:35 +0000[diff] [blame]269</p>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]270
Chris Lattner914ce462010-04-22 06:28:20 +0000[diff] [blame]271</div>
272
273<!--=========================================================================-->
274<div class="doc_subsection">
275<a name="orgchanges">LLVM Community Changes</a>
276</div>
277
278<div class="doc_text">
279
Chris Lattner922d00f2010-07-21 15:57:40 +0000[diff] [blame]280<p>In addition to changes to the code, between LLVM 2.7 and 2.8, a number of
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]281organization changes have happened:
282</p>
283
284<ul>
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]285</ul>
Chris Lattnerf8e0b4e2008-06-08 22:59:35 +0000[diff] [blame]286</div>
287
Chris Lattner8348b472008-06-08 21:58:17 +0000[diff] [blame]288<!--=========================================================================-->
Chris Lattnerea34f642008-06-08 21:34:41 +0000[diff] [blame]289<div class="doc_subsection">
Chris Lattner252b83d2008-02-06 18:00:06 +0000[diff] [blame]290<a name="majorfeatures">Major New Features</a>
291</div>
292
293<div class="doc_text">
294
Chris Lattner922d00f2010-07-21 15:57:40 +0000[diff] [blame]295<p>LLVM 2.8 includes several major new capabilities:</p>
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000[diff] [blame]296
297<ul>
Chris Lattner8dc5faf2010-09-05 20:49:45 +0000[diff] [blame]298<li>atomic lowering pass.</li>
299<li>RegionInfo pass: opt -regions analyze" or "opt -view-regions".
300<!-- Tobias Grosser --></li>
301<li>ARMGlobalMerge: <!-- Anton --> </li>
Chris Lattner702f2d42010-09-06 19:14:40 +0000[diff] [blame]302<li>llvm-diff</li>
Chris Lattner8170c102008-02-10 08:18:42 +0000[diff] [blame]303</ul>
Chris Lattnerdc910082010-03-17 06:41:58 +0000[diff] [blame]304
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000[diff] [blame]305</div>
306
Chris Lattner84977642007-09-21 03:54:09 +0000[diff] [blame]307<!--=========================================================================-->
308<div class="doc_subsection">
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]309<a name="coreimprovements">LLVM IR and Core Improvements</a>
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000[diff] [blame]310</div>
311
312<div class="doc_text">
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]313<p>LLVM IR has several new features for better support of new targets and that
314expose new optimization opportunities:</p>
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000[diff] [blame]315
Chris Lattner791f77b2008-06-05 06:25:56 +0000[diff] [blame]316<ul>
Gabor Greif17b59fe2010-07-21 10:20:08 +0000[diff] [blame]317
318<li>LLVM 2.8 changes the internal order of operands in <a
319 href="http://llvm.org/doxygen/classllvm_1_1InvokeInst.html"><tt>InvokeInst</tt></a>
320 and <a href="http://llvm.org/doxygen/classllvm_1_1CallInst.html"><tt>CallInst</tt></a>.
321 To be portable across releases, resort to <tt>CallSite</tt> and the
Gabor Greif50fb3302010-07-21 10:22:41 +0000[diff] [blame]322 high-level accessors, such as <tt>getCalledValue</tt> and <tt>setUnwindDest</tt>.
Gabor Greif17b59fe2010-07-21 10:20:08 +0000[diff] [blame]323</li>
Gabor Greif05006e22010-07-26 18:48:07 +0000[diff] [blame]324<li>
325 You can no longer pass use_iterators directly to cast<> (and similar), because
326 these routines tend to perform costly dereference operations more than once. You
327 have to dereference the iterators yourself and pass them in.
328</li>
Torok Edwin7c46cf02010-08-04 12:43:22 +0000[diff] [blame]329<li>
330 llvm.memcpy.*, llvm.memset.*, llvm.memmove.* (and possibly other?) intrinsics
331 take an extra parameter now (i1 isVolatile), totaling 5 parameters.
332 If you were creating these intrinsic calls and prototypes yourself (as opposed
333 to using Intrinsic::getDeclaration), you can use UpgradeIntrinsicFunction/UpgradeIntrinsicCall
334 to be portable accross releases.
335 Note that you cannot use Intrinsic::getDeclaration() in a backwards compatible
336 way (needs 2/3 types now, in 2.7 it needed just 1).
337</li>
338<li>
339 SetCurrentDebugLocation takes a DebugLoc now instead of a MDNode.
340 Change your code to use
341 SetCurrentDebugLocation(DebugLoc::getFromDILocation(...)).
342</li>
343<li>
344 VISIBILITY_HIDDEN is gone.
345</li>
346<li>
Owen Anderson87ebbc02010-08-04 18:27:08 +0000[diff] [blame]347 The <tt>RegisterPass</tt> and <tt>RegisterAnalysisGroup</tt> templates are
348 considered deprecated, but continue to function in LLVM 2.8. Clients are
349 strongly advised to use the upcoming <tt>INITIALIZE_PASS()</tt> and
350 <tt>INITIALIZE_AG_PASS()</tt> macros instead.
351<li>
Torok Edwin7c46cf02010-08-04 12:43:22 +0000[diff] [blame]352 SMDiagnostic takes different parameters now. //FIXME: how to upgrade?
353</li>
354<li>
Duncan Sands12881e72010-08-30 10:57:54 +0000[diff] [blame]355 The constructor for the Triple class no longer tries to understand odd triple
356 specifications. Frontends should ensure that they only pass valid triples to
357 LLVM. The Triple::normalize utility method has been added to help front-ends
358 deal with funky triples.
359<li>
Torok Edwin7c46cf02010-08-04 12:43:22 +0000[diff] [blame]360 Some APIs got renamed:
361 <ul>
362 <li>llvm_report_error -&gt; report_fatal_error</li>
363 <li>llvm_install_error_handler -&gt; install_fatal_error_handler</li>
364 <li>llvm::DwarfExceptionHandling -&gt; llvm::JITExceptionHandling</li>
365 </ul>
366</li>
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000[diff] [blame]367</ul>
Mikhail Glushenkovea65d7d2008-10-13 02:08:34 +0000[diff] [blame]368
Chris Lattnerf304ffc2008-02-10 08:17:19 +0000[diff] [blame]369</div>
370
371<!--=========================================================================-->
372<div class="doc_subsection">
Chris Lattneracce85d2008-02-10 07:46:44 +0000[diff] [blame]373<a name="optimizer">Optimizer Improvements</a>
374</div>
375
376<div class="doc_text">
377
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]378<p>In addition to a large array of minor performance tweaks and bug fixes, this
Chris Lattnerf3013872008-10-13 21:50:36 +0000[diff] [blame]379release includes a few major enhancements and additions to the optimizers:</p>
Chris Lattneracce85d2008-02-10 07:46:44 +0000[diff] [blame]380
381<ul>
382
Chris Lattner922d00f2010-07-21 15:57:40 +0000[diff] [blame]383<li></li>
Chris Lattnera54c1f72010-04-21 06:42:24 +0000[diff] [blame]384
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]385</ul>
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]386
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]387</div>
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]388
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]389
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]390<!--=========================================================================-->
391<div class="doc_subsection">
392<a name="executionengine">Interpreter and JIT Improvements</a>
393</div>
Chris Lattnerf3013872008-10-13 21:50:36 +0000[diff] [blame]394
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]395<div class="doc_text">
396
397<ul>
Chris Lattner922d00f2010-07-21 15:57:40 +0000[diff] [blame]398<li></li>
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]399
Chris Lattner0b832202008-06-08 02:45:07 +0000[diff] [blame]400</ul>
401
402</div>
403
404<!--=========================================================================-->
405<div class="doc_subsection">
Chris Lattner511433e2009-03-02 03:24:11 +0000[diff] [blame]406<a name="codegen">Target Independent Code Generator Improvements</a>
Chris Lattner0b832202008-06-08 02:45:07 +0000[diff] [blame]407</div>
408
409<div class="doc_text">
410
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000[diff] [blame]411<p>We have put a significant amount of work into the code generator
412infrastructure, which allows us to implement more aggressive algorithms and make
413it run faster:</p>
Chris Lattner0b832202008-06-08 02:45:07 +0000[diff] [blame]414
415<ul>
Chris Lattner922d00f2010-07-21 15:57:40 +0000[diff] [blame]416<li>MachO writer works.</li>
Chris Lattner84977642007-09-21 03:54:09 +0000[diff] [blame]417</ul>
Chris Lattner84977642007-09-21 03:54:09 +0000[diff] [blame]418</div>
419
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]420<!--=========================================================================-->
421<div class="doc_subsection">
422<a name="x86">X86-32 and X86-64 Target Improvements</a>
423</div>
424
425<div class="doc_text">
426<p>New features of the X86 target include:
427</p>
428
429<ul>
Chris Lattner922d00f2010-07-21 15:57:40 +0000[diff] [blame]430<li>The X86 backend now supports holding X87 floating point stack values
431 in registers across basic blocks, dramatically improving performance of code
432 that uses long double, and when targetting CPUs that don't support SSE.</li>
Chris Lattner511433e2009-03-02 03:24:11 +0000[diff] [blame]433
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]434</ul>
435
Chris Lattner917cc712009-03-02 02:37:32 +0000[diff] [blame]436</div>
Chris Lattner84977642007-09-21 03:54:09 +0000[diff] [blame]437
438<!--=========================================================================-->
439<div class="doc_subsection">
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]440<a name="ARM">ARM Target Improvements</a>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000[diff] [blame]441</div>
442
443<div class="doc_text">
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]444<p>New features of the ARM target include:
445</p>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000[diff] [blame]446
447<ul>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000[diff] [blame]448
Chris Lattner922d00f2010-07-21 15:57:40 +0000[diff] [blame]449<li></li>
Jim Grosbach41a77662010-04-22 18:33:31 +0000[diff] [blame]450
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]451</ul>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000[diff] [blame]452
Chris Lattnerc441fb82009-03-01 02:30:21 +0000[diff] [blame]453
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]454</div>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000[diff] [blame]455
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]456<!--=========================================================================-->
457<div class="doc_subsection">
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]458<a name="newapis">New Useful APIs</a>
459</div>
460
461<div class="doc_text">
462
463<p>This release includes a number of new APIs that are used internally, which
464 may also be useful for external clients.
465</p>
466
467<ul>
Chris Lattner922d00f2010-07-21 15:57:40 +0000[diff] [blame]468<li></li>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]469</ul>
470
471
472</div>
473
474<!--=========================================================================-->
475<div class="doc_subsection">
476<a name="otherimprovements">Other Improvements and New Features</a>
477</div>
478
479<div class="doc_text">
480<p>Other miscellaneous features include:</p>
481
482<ul>
Chris Lattner922d00f2010-07-21 15:57:40 +0000[diff] [blame]483<li></li>
Chris Lattnerc441fb82009-03-01 02:30:21 +0000[diff] [blame]484</ul>
485
486</div>
487
Chris Lattner77d29b12008-06-05 08:02:49 +0000[diff] [blame]488
489<!--=========================================================================-->
490<div class="doc_subsection">
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]491<a name="changes">Major Changes and Removed Features</a>
492</div>
493
494<div class="doc_text">
495
Chris Lattnereeb4da02008-10-13 22:06:31 +0000[diff] [blame]496<p>If you're already an LLVM user or developer with out-of-tree changes based
Chris Lattner922d00f2010-07-21 15:57:40 +0000[diff] [blame]497on LLVM 2.7, this section lists some "gotchas" that you may run into upgrading
Chris Lattnereeb4da02008-10-13 22:06:31 +0000[diff] [blame]498from the previous release.</p>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]499
500<ul>
Chris Lattner2295b5a2010-09-02 23:22:50 +0000[diff] [blame]501<li>.ll file doesn't produce #uses comments anymore, to get them, run a .bc file
502 through "llvm-dis --show-annotations".</li>
Chris Lattner885b6612010-08-28 16:33:36 +0000[diff] [blame]503<li>MSIL Backend removed.</li>
504<li>ABCD and SSI passes removed.</li>
505<li>'Union' LLVM IR feature removed.</li>
Chris Lattnerb7c85b42010-04-21 05:17:40 +0000[diff] [blame]506</ul>
Chris Lattnereeb4da02008-10-13 22:06:31 +0000[diff] [blame]507
508<p>In addition, many APIs have changed in this release. Some of the major LLVM
509API changes are:</p>
510
511<ul>
Devang Patelb34dd132008-10-14 20:03:43 +0000[diff] [blame]512</ul>
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]513
Chris Lattnerf6662f92008-10-13 17:57:36 +0000[diff] [blame]514</div>
515
516
517
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]518<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]519<div class="doc_section">
520 <a name="portability">Portability and Supported Platforms</a>
521</div>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]522<!-- *********************************************************************** -->
523
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]524<div class="doc_text">
525
John Criswell0b5b5e92004-12-08 20:35:47 +0000[diff] [blame]526<p>LLVM is known to work on the following platforms:</p>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]527
528<ul>
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000[diff] [blame]529<li>Intel and AMD machines (IA32, X86-64, AMD64, EMT-64) running Red Hat
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]530 Linux, Fedora Core, FreeBSD and AuroraUX (and probably other unix-like
531 systems).</li>
Chris Lattner914ce462010-04-22 06:28:20 +0000[diff] [blame]532<li>PowerPC and X86-based Mac OS X systems, running 10.4 and above in 32-bit
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]533 and 64-bit modes.</li>
Chris Lattner252b83d2008-02-06 18:00:06 +0000[diff] [blame]534<li>Intel and AMD machines running on Win32 using MinGW libraries (native).</li>
Chris Lattner57a460e2007-05-23 04:39:32 +0000[diff] [blame]535<li>Intel and AMD machines running on Win32 with the Cygwin libraries (limited
536 support is available for native builds with Visual C++).</li>
Chris Lattner7e23d6e2009-10-16 16:30:58 +0000[diff] [blame]537<li>Sun x86 and AMD64 machines running Solaris 10, OpenSolaris 0906.</li>
John Criswell9321fa82005-05-13 20:28:15 +0000[diff] [blame]538<li>Alpha-based machines running Debian GNU/Linux.</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]539</ul>
540
Chris Lattnerbc5786b2008-06-05 06:57:39 +0000[diff] [blame]541<p>The core LLVM infrastructure uses GNU autoconf to adapt itself
Brian Gaekeb0fd7612004-05-09 05:28:35 +0000[diff] [blame]542to the machine and operating system on which it is built. However, minor
543porting may be required to get LLVM to work on new platforms. We welcome your
544portability patches and reports of successful builds or error messages.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]545
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]546</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]547
548<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]549<div class="doc_section">
550 <a name="knownproblems">Known Problems</a>
551</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]552<!-- *********************************************************************** -->
553
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]554<div class="doc_text">
555
Mikhail Glushenkovf795ef02009-03-01 18:09:47 +0000[diff] [blame]556<p>This section contains significant known problems with the LLVM system,
Chris Lattnere18b32e2008-11-10 05:40:34 +0000[diff] [blame]557listed by component. If you run into a problem, please check the <a
Chris Lattnerc463b272005-10-29 07:07:09 +0000[diff] [blame]558href="http://llvm.org/bugs/">LLVM bug database</a> and submit a bug if
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]559there isn't already one.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]560
Chris Lattner477a1fd2010-03-17 17:25:49 +0000[diff] [blame]561<ul>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]562<li>LLVM will not correctly compile on Solaris and/or OpenSolaris
563using the stock GCC 3.x.x series 'out the box',
Chris Lattner554ee4a2009-11-03 21:50:09 +0000[diff] [blame]564See: <a href="GettingStarted.html#brokengcc">Broken versions of GCC and other tools</a>.
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]565However, A <a href="http://pkg.auroraux.org/GCC">Modern GCC Build</a>
566for x86/x86-64 has been made available from the third party AuroraUX Project
567that has been meticulously tested for bootstrapping LLVM &amp; Clang.</li>
Eric Christopher3aff6692010-08-05 20:38:39 +0000[diff] [blame]568<li>There have been reports of Solaris and/or OpenSolaris build failures due
569to an incompatibility in the nm program as well. The nm from binutils does seem
570to work.</li>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]571</ul>
572
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]573</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]574
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]575<!-- ======================================================================= -->
576<div class="doc_subsection">
577 <a name="experimental">Experimental features included with this release</a>
578</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]579
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]580<div class="doc_text">
581
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]582<p>The following components of this LLVM release are either untested, known to
583be broken or unreliable, or are in early development. These components should
584not be relied on, and bugs should not be filed against them, but they may be
585useful to some people. In particular, if you would like to work on one of these
Chris Lattner2b659ef2008-02-12 06:29:45 +0000[diff] [blame]586components, please contact us on the <a
587href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev list</a>.</p>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]588
589<ul>
Chris Lattner885b6612010-08-28 16:33:36 +0000[diff] [blame]590<li>The Alpha, SPU, MIPS, PIC16, Blackfin, MSP430, SystemZ and MicroBlaze
Wesley Peck7c4a1212010-03-18 14:31:30 +0000[diff] [blame]591 backends are experimental.</li>
Chris Lattner914ce462010-04-22 06:28:20 +0000[diff] [blame]592<li><tt>llc</tt> "<tt>-filetype=asm</tt>" (the default) is the only
Chris Lattner922d00f2010-07-21 15:57:40 +0000[diff] [blame]593 supported value for this option. XXX Update me</li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]594</ul>
595
596</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]597
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]598<!-- ======================================================================= -->
599<div class="doc_subsection">
Chris Lattner26299222006-11-18 07:51:14 +0000[diff] [blame]600 <a name="x86-be">Known problems with the X86 back-end</a>
John Criswellc0c186d2005-11-08 21:11:33 +0000[diff] [blame]601</div>
602
603<div class="doc_text">
604
605<ul>
Anton Korobeynikova6094be2008-06-08 10:24:13 +0000[diff] [blame]606 <li>The X86 backend does not yet support
607 all <a href="http://llvm.org/PR879">inline assembly that uses the X86
608 floating point stack</a>. It supports the 'f' and 't' constraints, but not
609 'u'.</li>
Duncan Sands47eff2b2008-06-08 19:38:43 +0000[diff] [blame]610 <li>Win64 code generation wasn't widely tested. Everything should work, but we
John Criswell524a5dd2009-03-02 15:28:15 +0000[diff] [blame]611 expect small issues to happen. Also, llvm-gcc cannot build the mingw64
Chris Lattner914ce462010-04-22 06:28:20 +0000[diff] [blame]612 runtime currently due to lack of support for the 'u' inline assembly
613 constraint and for X87 floating point inline assembly.</li>
Dan Gohman8207ba92008-06-08 23:05:11 +0000[diff] [blame]614 <li>The X86-64 backend does not yet support the LLVM IR instruction
Chris Lattner914ce462010-04-22 06:28:20 +0000[diff] [blame]615 <tt>va_arg</tt>. Currently, front-ends support variadic
Dan Gohman8207ba92008-06-08 23:05:11 +0000[diff] [blame]616 argument constructs on X86-64 by lowering them manually.</li>
Chris Lattner26299222006-11-18 07:51:14 +0000[diff] [blame]617</ul>
618
619</div>
620
621<!-- ======================================================================= -->
622<div class="doc_subsection">
623 <a name="ppc-be">Known problems with the PowerPC back-end</a>
624</div>
625
626<div class="doc_text">
627
628<ul>
Nicolas Geoffraye4285dc2007-05-15 09:21:28 +0000[diff] [blame]629<li>The Linux PPC32/ABI support needs testing for the interpreter and static
Chris Lattner57a460e2007-05-23 04:39:32 +0000[diff] [blame]630compilation, and lacks support for debug information.</li>
Chris Lattner26299222006-11-18 07:51:14 +0000[diff] [blame]631</ul>
632
633</div>
634
635<!-- ======================================================================= -->
636<div class="doc_subsection">
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000[diff] [blame]637 <a name="arm-be">Known problems with the ARM back-end</a>
638</div>
639
640<div class="doc_text">
641
642<ul>
Chris Lattner57a460e2007-05-23 04:39:32 +0000[diff] [blame]643<li>Thumb mode works only on ARMv6 or higher processors. On sub-ARMv6
Duncan Sandsc90d68b2007-09-26 15:59:54 +0000[diff] [blame]644processors, thumb programs can crash or produce wrong
Chris Lattner57a460e2007-05-23 04:39:32 +0000[diff] [blame]645results (<a href="http://llvm.org/PR1388">PR1388</a>).</li>
John Criswell524a5dd2009-03-02 15:28:15 +0000[diff] [blame]646<li>Compilation for ARM Linux OABI (old ABI) is supported but not fully tested.
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000[diff] [blame]647</li>
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000[diff] [blame]648</ul>
649
650</div>
651
652<!-- ======================================================================= -->
653<div class="doc_subsection">
Chris Lattner26299222006-11-18 07:51:14 +0000[diff] [blame]654 <a name="sparc-be">Known problems with the SPARC back-end</a>
655</div>
656
657<div class="doc_text">
658
659<ul>
John Criswell524a5dd2009-03-02 15:28:15 +0000[diff] [blame]660<li>The SPARC backend only supports the 32-bit SPARC ABI (-m32); it does not
Chris Lattner26299222006-11-18 07:51:14 +0000[diff] [blame]661 support the 64-bit SPARC ABI (-m64).</li>
662</ul>
663
664</div>
665
666<!-- ======================================================================= -->
667<div class="doc_subsection">
Bruno Cardoso Lopesb7e1a4f2008-10-25 14:56:26 +0000[diff] [blame]668 <a name="mips-be">Known problems with the MIPS back-end</a>
669</div>
670
671<div class="doc_text">
672
673<ul>
Bruno Cardoso Lopesb7e1a4f2008-10-25 14:56:26 +0000[diff] [blame]674<li>64-bit MIPS targets are not supported yet.</li>
675</ul>
676
677</div>
678
679<!-- ======================================================================= -->
680<div class="doc_subsection">
Chris Lattner26299222006-11-18 07:51:14 +0000[diff] [blame]681 <a name="alpha-be">Known problems with the Alpha back-end</a>
682</div>
683
684<div class="doc_text">
685
686<ul>
687
688<li>On 21164s, some rare FP arithmetic sequences which may trap do not have the
689appropriate nops inserted to ensure restartability.</li>
690
John Criswellc0c186d2005-11-08 21:11:33 +0000[diff] [blame]691</ul>
692</div>
693
Chris Lattner26299222006-11-18 07:51:14 +0000[diff] [blame]694<!-- ======================================================================= -->
695<div class="doc_subsection">
Chris Lattnerf3e5bc62007-05-14 06:56:09 +0000[diff] [blame]696 <a name="c-be">Known problems with the C back-end</a>
Chris Lattner26299222006-11-18 07:51:14 +0000[diff] [blame]697</div>
698
699<div class="doc_text">
700
701<ul>
Chris Lattner5733b272008-06-05 06:35:40 +0000[diff] [blame]702<li><a href="http://llvm.org/PR802">The C backend has only basic support for
703 inline assembly code</a>.</li>
Chris Lattner725a0d82007-09-26 06:01:35 +0000[diff] [blame]704<li><a href="http://llvm.org/PR1658">The C backend violates the ABI of common
705 C++ programs</a>, preventing intermixing between C++ compiled by the CBE and
Gabor Greif4906abe2009-03-02 12:02:51 +0000[diff] [blame]706 C++ code compiled with <tt>llc</tt> or native compilers.</li>
Duncan Sandsf74c0cc2008-02-10 13:40:55 +0000[diff] [blame]707<li>The C backend does not support all exception handling constructs.</li>
Duncan Sands50723a92009-02-25 11:51:54 +0000[diff] [blame]708<li>The C backend does not support arbitrary precision integers.</li>
Chris Lattner26299222006-11-18 07:51:14 +0000[diff] [blame]709</ul>
710
711</div>
John Criswellc0c186d2005-11-08 21:11:33 +0000[diff] [blame]712
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]713
714<!-- ======================================================================= -->
715<div class="doc_subsection">
Chris Lattnerc66bfef2010-03-17 04:41:49 +0000[diff] [blame]716 <a name="c-fe">Known problems with the llvm-gcc C and C++ front-end</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]717</div>
Chris Lattner47588f92003-10-02 05:07:23 +0000[diff] [blame]718
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]719<div class="doc_text">
Chris Lattnerc5d658a2006-03-03 00:34:26 +0000[diff] [blame]720
Chris Lattner5733b272008-06-05 06:35:40 +0000[diff] [blame]721<p>The only major language feature of GCC not supported by llvm-gcc is
722 the <tt>__builtin_apply</tt> family of builtins. However, some extensions
723 are only supported on some targets. For example, trampolines are only
Duncan Sands27aff872008-06-08 20:18:35 +0000[diff] [blame]724 supported on some targets (these are used when you take the address of a
725 nested function).</p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]726
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]727</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]728
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]729<!-- ======================================================================= -->
730<div class="doc_subsection">
Chris Lattner1eb4df62008-10-30 03:58:13 +0000[diff] [blame]731 <a name="fortran-fe">Known problems with the llvm-gcc Fortran front-end</a>
732</div>
733
734<div class="doc_text">
Gabor Greifba10fe02008-11-04 21:50:59 +0000[diff] [blame]735<ul>
Chris Lattner1eb4df62008-10-30 03:58:13 +0000[diff] [blame]736<li>Fortran support generally works, but there are still several unresolved bugs
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]737 in <a href="http://llvm.org/bugs/">Bugzilla</a>. Please see the
738 tools/gfortran component for details.</li>
Gabor Greifba10fe02008-11-04 21:50:59 +0000[diff] [blame]739</ul>
Chris Lattner1eb4df62008-10-30 03:58:13 +0000[diff] [blame]740</div>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]741
Chris Lattner2b659ef2008-02-12 06:29:45 +0000[diff] [blame]742<!-- ======================================================================= -->
743<div class="doc_subsection">
Chris Lattner5733b272008-06-05 06:35:40 +0000[diff] [blame]744 <a name="ada-fe">Known problems with the llvm-gcc Ada front-end</a>
Chris Lattner2b659ef2008-02-12 06:29:45 +0000[diff] [blame]745</div>
746
747<div class="doc_text">
John Criswell524a5dd2009-03-02 15:28:15 +0000[diff] [blame]748The llvm-gcc 4.2 Ada compiler works fairly well; however, this is not a mature
749technology, and problems should be expected.
Chris Lattner2b659ef2008-02-12 06:29:45 +0000[diff] [blame]750<ul>
Duncan Sands27aff872008-06-08 20:18:35 +0000[diff] [blame]751<li>The Ada front-end currently only builds on X86-32. This is mainly due
John Criswell524a5dd2009-03-02 15:28:15 +0000[diff] [blame]752to lack of trampoline support (pointers to nested functions) on other platforms.
753However, it <a href="http://llvm.org/PR2006">also fails to build on X86-64</a>
Chris Lattner2b659ef2008-02-12 06:29:45 +0000[diff] [blame]754which does support trampolines.</li>
755<li>The Ada front-end <a href="http://llvm.org/PR2007">fails to bootstrap</a>.
Duncan Sands326a4982009-02-25 11:59:06 +0000[diff] [blame]756This is due to lack of LLVM support for <tt>setjmp</tt>/<tt>longjmp</tt> style
757exception handling, which is used internally by the compiler.
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]758Workaround: configure with <tt>--disable-bootstrap</tt>.</li>
Duncan Sands978bcee2008-10-13 17:27:23 +0000[diff] [blame]759<li>The c380004, <a href="http://llvm.org/PR2010">c393010</a>
760and <a href="http://llvm.org/PR2421">cxg2021</a> ACATS tests fail
Duncan Sands326a4982009-02-25 11:59:06 +0000[diff] [blame]761(c380004 also fails with gcc-4.2 mainline).
762If the compiler is built with checks disabled then <a href="http://llvm.org/PR2010">c393010</a>
763causes the compiler to go into an infinite loop, using up all system memory.</li>
Duncan Sandsdd3e6722009-03-02 16:35:57 +0000[diff] [blame]764<li>Some GCC specific Ada tests continue to crash the compiler.</li>
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]765<li>The <tt>-E</tt> binder option (exception backtraces)
Chris Lattner2b659ef2008-02-12 06:29:45 +0000[diff] [blame]766<a href="http://llvm.org/PR1982">does not work</a> and will result in programs
Chris Lattner61358ab2009-10-13 17:48:04 +0000[diff] [blame]767crashing if an exception is raised. Workaround: do not use <tt>-E</tt>.</li>
Chris Lattner2b659ef2008-02-12 06:29:45 +0000[diff] [blame]768<li>Only discrete types <a href="http://llvm.org/PR1981">are allowed to start
769or finish at a non-byte offset</a> in a record. Workaround: do not pack records
770or use representation clauses that result in a field of a non-discrete type
771starting or finishing in the middle of a byte.</li>
Chris Lattnere6e1b352008-06-08 21:19:07 +0000[diff] [blame]772<li>The <tt>lli</tt> interpreter <a href="http://llvm.org/PR2009">considers
773'main' as generated by the Ada binder to be invalid</a>.
774Workaround: hand edit the file to use pointers for <tt>argv</tt> and
775<tt>envp</tt> rather than integers.</li>
776<li>The <tt>-fstack-check</tt> option <a href="http://llvm.org/PR2008">is
777ignored</a>.</li>
Chris Lattner2b659ef2008-02-12 06:29:45 +0000[diff] [blame]778</ul>
779</div>
780
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]781<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]782<div class="doc_section">
783 <a name="additionalinfo">Additional Information</a>
784</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]785<!-- *********************************************************************** -->
786
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]787<div class="doc_text">
788
Chris Lattner416db102005-05-16 17:13:10 +0000[diff] [blame]789<p>A wide variety of additional information is available on the <a
Chris Lattnerb4b0ce72007-05-18 00:44:29 +0000[diff] [blame]790href="http://llvm.org">LLVM web page</a>, in particular in the <a
791href="http://llvm.org/docs/">documentation</a> section. The web page also
Reid Spencer669ed452007-07-09 08:04:31 +0000[diff] [blame]792contains versions of the API documentation which is up-to-date with the
793Subversion version of the source code.
Misha Brukman109d9e82005-03-30 19:14:24 +0000[diff] [blame]794You can access versions of these documents specific to this release by going
795into the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]796
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]797<p>If you have any questions or comments about LLVM, please feel free to contact
Chris Lattnerc463b272005-10-29 07:07:09 +0000[diff] [blame]798us via the <a href="http://llvm.org/docs/#maillist"> mailing
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]799lists</a>.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]800
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]801</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]802
803<!-- *********************************************************************** -->
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]804
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]805<hr>
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]806<address>
Misha Brukman38847d52003-12-21 22:53:21 +0000[diff] [blame]807 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman44408702008-12-11 17:34:48 +0000[diff] [blame]808 src="http://jigsaw.w3.org/css-validator/images/vcss-blue" alt="Valid CSS"></a>
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]809 <a href="http://validator.w3.org/check/referer"><img
Misha Brukman44408702008-12-11 17:34:48 +0000[diff] [blame]810 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]811
Chris Lattnerb4b0ce72007-05-18 00:44:29 +0000[diff] [blame]812 <a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]813 Last modified: $Date$
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]814</address>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]815
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]816</body>
817</html>