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gerrit-public.fairphone.software / toolchain / llvm-project / 9440d1c008e74ee76e8ba394dcd467f152a72083 / . / llvm / docs / ReleaseNotes.html
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Misha Brukman80731b92003-11-22 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 Spencere4190fa2004-11-18 18:38:58 +0000[diff] [blame]5 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]6 <link rel="stylesheet" href="llvm.css" type="text/css">
Dan Gohman62af9d22010-05-03 23:51:05 +0000[diff] [blame]7 <title>LLVM 2.8 Release Notes</title>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]8</head>
9<body>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]10
Dan Gohman62af9d22010-05-03 23:51:05 +0000[diff] [blame]11<div class="doc_title">LLVM 2.8 Release Notes</div>
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]12
Chris Lattnerc871bac2010-03-17 04:02:39 +0000[diff] [blame]13<img align=right src="http://llvm.org/img/DragonSmall.png"
Gabor Greif27b166352010-04-22 10:21:43 +0000[diff] [blame]14 width="136" height="136" alt="LLVM Dragon Logo">
Chris Lattnerc871bac2010-03-17 04:02:39 +0000[diff] [blame]15
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]16<ol>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]17 <li><a href="#intro">Introduction</a></li>
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]18 <li><a href="#subproj">Sub-project Status Update</a></li>
Dan Gohman62af9d22010-05-03 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 Lattner77a51732004-04-30 22:17:12 +0000[diff] [blame]21 <li><a href="GettingStarted.html">Installation Instructions</a></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]22 <li><a href="#portability">Portability and Supported Platforms</a></li>
Dan Gohmanad888912008-10-14 16:23:02 +0000[diff] [blame]23 <li><a href="#knownproblems">Known Problems</a></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]24 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]25</ol>
26
Chris Lattner020e1fc2004-05-23 21:07:27 +0000[diff] [blame]27<div class="doc_author">
Dan Gohmanad888912008-10-14 16:23:02 +0000[diff] [blame]28 <p>Written by the <a href="http://llvm.org">LLVM Team</a></p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]29</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]30
Chris Lattner656db162010-04-22 05:41:35 +0000[diff] [blame]31<h1 style="color:red">These are in-progress notes for the upcoming LLVM 2.8
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]32release.<br>
33You may prefer the
Dan Gohman62af9d22010-05-03 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 Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]36
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]37<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]38<div class="doc_section">
39 <a name="intro">Introduction</a>
40</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]41<!-- *********************************************************************** -->
42
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]43<div class="doc_text">
44
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]45<p>This document contains the release notes for the LLVM Compiler
Dan Gohman3b763f42010-05-03 23:52:21 +0000[diff] [blame]46Infrastructure, release 2.8. Here we describe the status of LLVM, including
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]47major improvements from the previous release and significant known problems.
Mikhail Glushenkov25422542009-03-01 18:09:47 +0000[diff] [blame]48All LLVM releases may be downloaded from the <a
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]49href="http://llvm.org/releases/">LLVM releases web site</a>.</p>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]50
Chris Lattnerb5bb5972004-12-07 08:04:13 +0000[diff] [blame]51<p>For more information about LLVM, including information about the latest
Chris Lattnera69595e2005-10-29 07:07:09 +0000[diff] [blame]52release, please check out the <a href="http://llvm.org/">main LLVM
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]53web site</a>. If you have questions or comments, the <a
Chris Lattner0b1c9a52010-03-17 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 Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]56
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]57<p>Note that if you are reading this file from a Subversion checkout or the
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]58main LLVM web page, this document applies to the <i>next</i> release, not the
Gabor Greif355f81c2008-10-14 11:00:32 +0000[diff] [blame]59current one. To see the release notes for a specific release, please see the
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]60<a href="http://llvm.org/releases/">releases page</a>.</p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]61
62</div>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]63
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]64
Chris Lattneraa61f412009-10-13 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 Lattner13ee7952010-08-28 04:09:24 +0000[diff] [blame]70 GEPSplitterPass
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]71-->
72
73
Dan Gohman62af9d22010-05-03 23:51:05 +0000[diff] [blame]74<!-- Features that need text if they're finished for 2.8:
Chris Lattnera67df2d2010-04-22 06:28:20 +0000[diff] [blame]75 combiner-aa?
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]76 strong phi elim
Chris Lattner87e04952010-04-21 05:17:40 +0000[diff] [blame]77 llvm.dbg.value: variable debug info for optimized code
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]78 loop dependence analysis
Chris Lattnerbd244042010-08-28 16:33:36 +0000[diff] [blame]79 TBAA
Chris Lattner2b8a52e2008-02-10 07:46:44 +0000[diff] [blame]80 -->
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]81
Chris Lattnerc4d68542008-10-12 19:47:48 +0000[diff] [blame]82 <!-- for announcement email:
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]83 Logo web page.
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]84 Many new papers added to /pubs/
Chris Lattnerd02da042009-02-25 06:34:50 +0000[diff] [blame]85 -->
Chris Lattner2b8a52e2008-02-10 07:46:44 +0000[diff] [blame]86
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]87<!-- *********************************************************************** -->
88<div class="doc_section">
89 <a name="subproj">Sub-project Status Update</a>
Chris Lattner625a3d82008-06-08 21:34:41 +0000[diff] [blame]90</div>
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]91<!-- *********************************************************************** -->
Chris Lattner625a3d82008-06-08 21:34:41 +0000[diff] [blame]92
93<div class="doc_text">
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]94<p>
Dan Gohman62af9d22010-05-03 23:51:05 +0000[diff] [blame]95The LLVM 2.8 distribution currently consists of code from the core LLVM
Chris Lattneraa61f412009-10-13 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 Wendlingf170d2e2009-03-02 04:28:57 +0000[diff] [blame]100</p>
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]101
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]102</div>
103
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]104
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]105<!--=========================================================================-->
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]106<div class="doc_subsection">
Chris Lattner44c09cd2008-10-13 18:11:54 +0000[diff] [blame]107<a name="clang">Clang: C/C++/Objective-C Frontend Toolkit</a>
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]108</div>
109
110<div class="doc_text">
111
Chris Lattner5de7f6e2010-04-26 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 Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]119
Chris Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]120<p>In the LLVM 2.8 time-frame, the Clang team has made many improvements:</p>
Bill Wendlingef362462008-10-27 09:27:33 +0000[diff] [blame]121
Daniel Dunbarc11b40f2008-10-14 23:25:09 +0000[diff] [blame]122<ul>
David Chisnall17dff472010-04-25 19:13:33 +0000[diff] [blame]123
Bill Wendling87adbe42009-03-02 04:28:18 +0000[diff] [blame]124</ul>
Chris Lattner44c09cd2008-10-13 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 Lattner2284b6a2010-04-22 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 Lattnerbcffa5a2008-10-14 00:52:49 +0000[diff] [blame]140
Chris Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]141<p>In the LLVM 2.8 time-frame,
Chris Lattner2284b6a2010-04-22 06:38:11 +0000[diff] [blame]142</p>
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]143
144</div>
145
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]146<!--=========================================================================-->
147<div class="doc_subsection">
Nicolas Geoffraye5ec9322008-10-14 19:23:04 +0000[diff] [blame]148<a name="vmkit">VMKit: JVM/CLI Virtual Machine Implementation</a>
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]149</div>
150
151<div class="doc_text">
152<p>
Nicolas Geoffraye5ec9322008-10-14 19:23:04 +0000[diff] [blame]153The <a href="http://vmkit.llvm.org/">VMKit project</a> is an implementation of
Chris Lattneraa61f412009-10-13 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 Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]157
Chris Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]158<p>With the release of LLVM 2.8, ...</p>
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]159
160</div>
161
Chris Lattneraa61f412009-10-13 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 Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]181License, a "BSD-style" license. New in LLVM 2.8:
182
183Soft float support
184</p>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]185
186</div>
187
188<!--=========================================================================-->
189<div class="doc_subsection">
Duncan Sands92452b92010-04-02 09:23:15 +0000[diff] [blame]190<a name="dragonegg">DragonEgg: llvm-gcc ported to gcc-4.5</a>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]191</div>
192
193<div class="doc_text">
194<p>
Duncan Sands92452b92010-04-02 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 Sands4dd125e2010-04-20 19:40:58 +0000[diff] [blame]213supported, and only on linux and darwin (darwin needs an additional gcc patch).
Duncan Sands92452b92010-04-02 09:23:15 +0000[diff] [blame]214</p>
215
216<p>
Chris Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]2172.8 status here.
Chris Lattneraa61f412009-10-13 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 Lattner2284b6a2010-04-22 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 Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]238</p>
239
Chris Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]240<p>2.8 status here</p>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]241</div>
242
243
Chris Lattner53e06f92009-02-26 22:33:38 +0000[diff] [blame]244<!-- *********************************************************************** -->
245<div class="doc_section">
Chris Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]246 <a name="externalproj">External Open Source Projects Using LLVM 2.8</a>
Chris Lattner53e06f92009-02-26 22:33:38 +0000[diff] [blame]247</div>
248<!-- *********************************************************************** -->
249
Chris Lattneraa61f412009-10-13 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 Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]254 projects that have already been updated to work with LLVM 2.8.</p>
Chris Lattnerdf85c892010-04-26 17:38:10 +0000[diff] [blame]255</div>
256
Chris Lattner64694df2010-04-22 21:34:16 +0000[diff] [blame]257
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]258<!-- *********************************************************************** -->
259<div class="doc_section">
Chris Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]260 <a name="whatsnew">What's New in LLVM 2.8?</a>
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]261</div>
262<!-- *********************************************************************** -->
263
Chris Lattnerb7bc2aa2008-06-08 22:59:35 +0000[diff] [blame]264<div class="doc_text">
265
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]266<p>This release includes a huge number of bug fixes, performance tweaks and
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]267minor improvements. Some of the major improvements and new features are listed
268in this section.
Chris Lattnerb7bc2aa2008-06-08 22:59:35 +0000[diff] [blame]269</p>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]270
Chris Lattnera67df2d2010-04-22 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 Lattnerb3fa6bf2010-07-21 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 Lattner87e04952010-04-21 05:17:40 +0000[diff] [blame]281organization changes have happened:
282</p>
283
284<ul>
Chris Lattner87e04952010-04-21 05:17:40 +0000[diff] [blame]285</ul>
Chris Lattnerb7bc2aa2008-06-08 22:59:35 +0000[diff] [blame]286</div>
287
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]288<!--=========================================================================-->
Chris Lattner625a3d82008-06-08 21:34:41 +0000[diff] [blame]289<div class="doc_subsection">
Chris Lattnercdc44ed2008-02-06 18:00:06 +0000[diff] [blame]290<a name="majorfeatures">Major New Features</a>
291</div>
292
293<div class="doc_text">
294
Chris Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]295<p>LLVM 2.8 includes several major new capabilities:</p>
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]296
297<ul>
Chris Lattner8c26cee2010-09-05 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 Lattner8128ca12010-09-06 19:14:40 +0000[diff] [blame]302<li>llvm-diff</li>
Chris Lattner458e79f2008-02-10 08:18:42 +0000[diff] [blame]303</ul>
Chris Lattner10a3cc42010-03-17 06:41:58 +0000[diff] [blame]304
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]305</div>
306
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]307<!--=========================================================================-->
308<div class="doc_subsection">
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]309<a name="coreimprovements">LLVM IR and Core Improvements</a>
Chris Lattnerdd6acc02008-02-10 08:17:19 +0000[diff] [blame]310</div>
311
312<div class="doc_text">
Chris Lattneraa61f412009-10-13 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 Lattnerdd6acc02008-02-10 08:17:19 +0000[diff] [blame]315
Chris Lattnerb7112222008-06-05 06:25:56 +0000[diff] [blame]316<ul>
Gabor Greif4b17e652010-07-21 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 Greif930894f2010-07-21 10:22:41 +0000[diff] [blame]322 high-level accessors, such as <tt>getCalledValue</tt> and <tt>setUnwindDest</tt>.
Gabor Greif4b17e652010-07-21 10:20:08 +0000[diff] [blame]323</li>
Gabor Greifed79dcb2010-07-26 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 Edwine6f478f2010-08-04 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 Andersonf16eb372010-08-04 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 Edwine6f478f2010-08-04 12:43:22 +0000[diff] [blame]352 SMDiagnostic takes different parameters now. //FIXME: how to upgrade?
353</li>
354<li>
Duncan Sands1b6744a2010-08-30 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 Edwine6f478f2010-08-04 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 Lattnerdd6acc02008-02-10 08:17:19 +0000[diff] [blame]367</ul>
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]368
Chris Lattnerdd6acc02008-02-10 08:17:19 +0000[diff] [blame]369</div>
370
371<!--=========================================================================-->
372<div class="doc_subsection">
Chris Lattner2b8a52e2008-02-10 07:46:44 +0000[diff] [blame]373<a name="optimizer">Optimizer Improvements</a>
374</div>
375
376<div class="doc_text">
377
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]378<p>In addition to a large array of minor performance tweaks and bug fixes, this
Chris Lattner25879d72008-10-13 21:50:36 +0000[diff] [blame]379release includes a few major enhancements and additions to the optimizers:</p>
Chris Lattner2b8a52e2008-02-10 07:46:44 +0000[diff] [blame]380
381<ul>
382
Chris Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]383<li></li>
Chris Lattnera668b452010-04-21 06:42:24 +0000[diff] [blame]384
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]385</ul>
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]386
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]387</div>
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]388
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]389
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]390<!--=========================================================================-->
391<div class="doc_subsection">
392<a name="executionengine">Interpreter and JIT Improvements</a>
393</div>
Chris Lattner25879d72008-10-13 21:50:36 +0000[diff] [blame]394
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]395<div class="doc_text">
396
397<ul>
Chris Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]398<li></li>
Chris Lattner87e04952010-04-21 05:17:40 +0000[diff] [blame]399
Chris Lattner7795ea92008-06-08 02:45:07 +0000[diff] [blame]400</ul>
401
402</div>
403
404<!--=========================================================================-->
405<div class="doc_subsection">
Chris Lattnerd434bfb2009-03-02 03:24:11 +0000[diff] [blame]406<a name="codegen">Target Independent Code Generator Improvements</a>
Chris Lattner7795ea92008-06-08 02:45:07 +0000[diff] [blame]407</div>
408
409<div class="doc_text">
410
Mikhail Glushenkov25422542009-03-01 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 Lattner7795ea92008-06-08 02:45:07 +0000[diff] [blame]414
415<ul>
Chris Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]416<li>MachO writer works.</li>
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]417</ul>
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]418</div>
419
Chris Lattnerd1094e02009-03-02 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 Lattnerb3fa6bf2010-07-21 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 Lattnerd434bfb2009-03-02 03:24:11 +0000[diff] [blame]433
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]434</ul>
435
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]436</div>
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]437
438<!--=========================================================================-->
439<div class="doc_subsection">
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]440<a name="ARM">ARM Target Improvements</a>
Chris Lattnerc92d7692009-03-01 02:30:21 +0000[diff] [blame]441</div>
442
443<div class="doc_text">
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]444<p>New features of the ARM target include:
445</p>
Chris Lattnerc92d7692009-03-01 02:30:21 +0000[diff] [blame]446
447<ul>
Chris Lattnerc92d7692009-03-01 02:30:21 +0000[diff] [blame]448
Chris Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]449<li></li>
Jim Grosbach96284682010-04-22 18:33:31 +0000[diff] [blame]450
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]451</ul>
Chris Lattnerc92d7692009-03-01 02:30:21 +0000[diff] [blame]452
Chris Lattnerc92d7692009-03-01 02:30:21 +0000[diff] [blame]453
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]454</div>
Chris Lattnerc92d7692009-03-01 02:30:21 +0000[diff] [blame]455
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]456<!--=========================================================================-->
457<div class="doc_subsection">
Chris Lattneraa61f412009-10-13 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 Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]468<li></li>
Chris Lattneraa61f412009-10-13 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 Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]483<li></li>
Chris Lattnerc92d7692009-03-01 02:30:21 +0000[diff] [blame]484</ul>
485
486</div>
487
Chris Lattner6cb64032008-06-05 08:02:49 +0000[diff] [blame]488
489<!--=========================================================================-->
490<div class="doc_subsection">
Chris Lattner1e4d5bc2008-10-13 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 Lattner934e2d42008-10-13 22:06:31 +0000[diff] [blame]496<p>If you're already an LLVM user or developer with out-of-tree changes based
Chris Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]497on LLVM 2.7, this section lists some "gotchas" that you may run into upgrading
Chris Lattner934e2d42008-10-13 22:06:31 +0000[diff] [blame]498from the previous release.</p>
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]499
500<ul>
Chris Lattnerfc561ba2010-09-02 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 Lattnerbd244042010-08-28 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 Lattner87e04952010-04-21 05:17:40 +0000[diff] [blame]506</ul>
Chris Lattner934e2d42008-10-13 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 Pateldbf83832008-10-14 20:03:43 +0000[diff] [blame]512</ul>
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]513
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]514</div>
515
516
517
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]518<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]519<div class="doc_section">
520 <a name="portability">Portability and Supported Platforms</a>
521</div>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]522<!-- *********************************************************************** -->
523
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]524<div class="doc_text">
525
John Criswell64307722004-12-08 20:35:47 +0000[diff] [blame]526<p>LLVM is known to work on the following platforms:</p>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]527
528<ul>
Mikhail Glushenkov25422542009-03-01 18:09:47 +0000[diff] [blame]529<li>Intel and AMD machines (IA32, X86-64, AMD64, EMT-64) running Red Hat
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]530 Linux, Fedora Core, FreeBSD and AuroraUX (and probably other unix-like
531 systems).</li>
Chris Lattnera67df2d2010-04-22 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 Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]533 and 64-bit modes.</li>
Chris Lattnercdc44ed2008-02-06 18:00:06 +0000[diff] [blame]534<li>Intel and AMD machines running on Win32 using MinGW libraries (native).</li>
Chris Lattnerbee7b322007-05-23 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 Lattner51948622009-10-16 16:30:58 +0000[diff] [blame]537<li>Sun x86 and AMD64 machines running Solaris 10, OpenSolaris 0906.</li>
John Criswelld5234922005-05-13 20:28:15 +0000[diff] [blame]538<li>Alpha-based machines running Debian GNU/Linux.</li>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]539</ul>
540
Chris Lattner618a99f2008-06-05 06:57:39 +0000[diff] [blame]541<p>The core LLVM infrastructure uses GNU autoconf to adapt itself
Brian Gaekee3e557e2004-05-09 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 Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]545
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]546</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]547
548<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]549<div class="doc_section">
550 <a name="knownproblems">Known Problems</a>
551</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]552<!-- *********************************************************************** -->
553
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]554<div class="doc_text">
555
Mikhail Glushenkov25422542009-03-01 18:09:47 +0000[diff] [blame]556<p>This section contains significant known problems with the LLVM system,
Chris Lattner2a092392008-11-10 05:40:34 +0000[diff] [blame]557listed by component. If you run into a problem, please check the <a
Chris Lattnera69595e2005-10-29 07:07:09 +0000[diff] [blame]558href="http://llvm.org/bugs/">LLVM bug database</a> and submit a bug if
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]559there isn't already one.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]560
Chris Lattner6aba4862010-03-17 17:25:49 +0000[diff] [blame]561<ul>
Chris Lattneraa61f412009-10-13 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 Lattner6e41c792009-11-03 21:50:09 +0000[diff] [blame]564See: <a href="GettingStarted.html#brokengcc">Broken versions of GCC and other tools</a>.
Chris Lattneraa61f412009-10-13 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 Christopherfa5d2412010-08-05 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 Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]571</ul>
572
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]573</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]574
Chris Lattnerb911de42004-03-14 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 Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]579
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]580<div class="doc_text">
581
Misha Brukmanfa50a222004-05-12 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 Lattnere38ac152008-02-12 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 Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]588
589<ul>
Chris Lattnerbd244042010-08-28 16:33:36 +0000[diff] [blame]590<li>The Alpha, SPU, MIPS, PIC16, Blackfin, MSP430, SystemZ and MicroBlaze
Wesley Peck3aa84e52010-03-18 14:31:30 +0000[diff] [blame]591 backends are experimental.</li>
Chris Lattnera67df2d2010-04-22 06:28:20 +0000[diff] [blame]592<li><tt>llc</tt> "<tt>-filetype=asm</tt>" (the default) is the only
Chris Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]593 supported value for this option. XXX Update me</li>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]594</ul>
595
596</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]597
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]598<!-- ======================================================================= -->
599<div class="doc_subsection">
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]600 <a name="x86-be">Known problems with the X86 back-end</a>
John Criswell3bdbd302005-11-08 21:11:33 +0000[diff] [blame]601</div>
602
603<div class="doc_text">
604
605<ul>
Anton Korobeynikov486c7d32008-06-08 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 Sands0bc15262008-06-08 19:38:43 +0000[diff] [blame]610 <li>Win64 code generation wasn't widely tested. Everything should work, but we
John Criswellea03c9d2009-03-02 15:28:15 +0000[diff] [blame]611 expect small issues to happen. Also, llvm-gcc cannot build the mingw64
Chris Lattnera67df2d2010-04-22 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 Gohman721b3722008-06-08 23:05:11 +0000[diff] [blame]614 <li>The X86-64 backend does not yet support the LLVM IR instruction
Chris Lattnera67df2d2010-04-22 06:28:20 +0000[diff] [blame]615 <tt>va_arg</tt>. Currently, front-ends support variadic
Dan Gohman721b3722008-06-08 23:05:11 +0000[diff] [blame]616 argument constructs on X86-64 by lowering them manually.</li>
Chris Lattnerb81f10e2006-11-18 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 Geoffray77d99502007-05-15 09:21:28 +0000[diff] [blame]629<li>The Linux PPC32/ABI support needs testing for the interpreter and static
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]630compilation, and lacks support for debug information.</li>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]631</ul>
632
633</div>
634
635<!-- ======================================================================= -->
636<div class="doc_subsection">
Chris Lattner97beb512007-05-14 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 Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]643<li>Thumb mode works only on ARMv6 or higher processors. On sub-ARMv6
Duncan Sands47fc0a22007-09-26 15:59:54 +0000[diff] [blame]644processors, thumb programs can crash or produce wrong
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]645results (<a href="http://llvm.org/PR1388">PR1388</a>).</li>
John Criswellea03c9d2009-03-02 15:28:15 +0000[diff] [blame]646<li>Compilation for ARM Linux OABI (old ABI) is supported but not fully tested.
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]647</li>
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]648</ul>
649
650</div>
651
652<!-- ======================================================================= -->
653<div class="doc_subsection">
Chris Lattnerb81f10e2006-11-18 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 Criswellea03c9d2009-03-02 15:28:15 +0000[diff] [blame]660<li>The SPARC backend only supports the 32-bit SPARC ABI (-m32); it does not
Chris Lattnerb81f10e2006-11-18 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 Lopes24eb3de2008-10-25 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 Lopes24eb3de2008-10-25 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 Lattnerb81f10e2006-11-18 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 Criswell3bdbd302005-11-08 21:11:33 +0000[diff] [blame]691</ul>
692</div>
693
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]694<!-- ======================================================================= -->
695<div class="doc_subsection">
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]696 <a name="c-be">Known problems with the C back-end</a>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]697</div>
698
699<div class="doc_text">
700
701<ul>
Chris Lattnera1a4c9a2008-06-05 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 Lattner8e061162007-09-26 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 Greif75b2f762009-03-02 12:02:51 +0000[diff] [blame]706 C++ code compiled with <tt>llc</tt> or native compilers.</li>
Duncan Sandse09506a2008-02-10 13:40:55 +0000[diff] [blame]707<li>The C backend does not support all exception handling constructs.</li>
Duncan Sands3aa36732009-02-25 11:51:54 +0000[diff] [blame]708<li>The C backend does not support arbitrary precision integers.</li>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]709</ul>
710
711</div>
John Criswell3bdbd302005-11-08 21:11:33 +0000[diff] [blame]712
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]713
714<!-- ======================================================================= -->
715<div class="doc_subsection">
Chris Lattner0b1c9a52010-03-17 04:41:49 +0000[diff] [blame]716 <a name="c-fe">Known problems with the llvm-gcc C and C++ front-end</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]717</div>
Chris Lattner178f3db2003-10-02 05:07:23 +0000[diff] [blame]718
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]719<div class="doc_text">
Chris Lattner72a269f2006-03-03 00:34:26 +0000[diff] [blame]720
Chris Lattnera1a4c9a2008-06-05 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 Sands56448462008-06-08 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]726
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]727</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]728
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]729<!-- ======================================================================= -->
730<div class="doc_subsection">
Chris Lattner7292fb12008-10-30 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 Greife5f9d672008-11-04 21:50:59 +0000[diff] [blame]735<ul>
Chris Lattner7292fb12008-10-30 03:58:13 +0000[diff] [blame]736<li>Fortran support generally works, but there are still several unresolved bugs
Chris Lattneraa61f412009-10-13 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 Greife5f9d672008-11-04 21:50:59 +0000[diff] [blame]739</ul>
Chris Lattner7292fb12008-10-30 03:58:13 +0000[diff] [blame]740</div>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]741
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]742<!-- ======================================================================= -->
743<div class="doc_subsection">
Chris Lattnera1a4c9a2008-06-05 06:35:40 +0000[diff] [blame]744 <a name="ada-fe">Known problems with the llvm-gcc Ada front-end</a>
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]745</div>
746
747<div class="doc_text">
John Criswellea03c9d2009-03-02 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 Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]750<ul>
Duncan Sands56448462008-06-08 20:18:35 +0000[diff] [blame]751<li>The Ada front-end currently only builds on X86-32. This is mainly due
John Criswellea03c9d2009-03-02 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 Lattnere38ac152008-02-12 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 Sandsd34bf762009-02-25 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 Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]758Workaround: configure with <tt>--disable-bootstrap</tt>.</li>
Duncan Sandsaef747f2008-10-13 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 Sandsd34bf762009-02-25 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 Sands2dbb00e2009-03-02 16:35:57 +0000[diff] [blame]764<li>Some GCC specific Ada tests continue to crash the compiler.</li>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]765<li>The <tt>-E</tt> binder option (exception backtraces)
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]766<a href="http://llvm.org/PR1982">does not work</a> and will result in programs
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]767crashing if an exception is raised. Workaround: do not use <tt>-E</tt>.</li>
Chris Lattnere38ac152008-02-12 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 Lattnerb076b002008-06-08 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 Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]778</ul>
779</div>
780
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]781<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]782<div class="doc_section">
783 <a name="additionalinfo">Additional Information</a>
784</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]785<!-- *********************************************************************** -->
786
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]787<div class="doc_text">
788
Chris Lattnercb5596d2005-05-16 17:13:10 +0000[diff] [blame]789<p>A wide variety of additional information is available on the <a
Chris Lattnere0c1df42007-05-18 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 Spencerc7f87f22007-07-09 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 Brukman96158092005-03-30 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 Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]796
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]797<p>If you have any questions or comments about LLVM, please feel free to contact
Chris Lattnera69595e2005-10-29 07:07:09 +0000[diff] [blame]798us via the <a href="http://llvm.org/docs/#maillist"> mailing
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]799lists</a>.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]800
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]801</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]802
803<!-- *********************************************************************** -->
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]804
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]805<hr>
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]806<address>
Misha Brukman8834af92003-12-21 22:53:21 +0000[diff] [blame]807 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman86242e12008-12-11 17:34:48 +0000[diff] [blame]808 src="http://jigsaw.w3.org/css-validator/images/vcss-blue" alt="Valid CSS"></a>
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]809 <a href="http://validator.w3.org/check/referer"><img
Misha Brukman86242e12008-12-11 17:34:48 +0000[diff] [blame]810 src="http://www.w3.org/Icons/valid-html401-blue" alt="Valid HTML 4.01"></a>
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]811
Chris Lattnere0c1df42007-05-18 00:44:29 +0000[diff] [blame]812 <a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]813 Last modified: $Date$
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]814</address>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]815
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]816</body>
817</html>