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gerrit-public.fairphone.software / fp2-dev / platform / external / llvm / 6fd928d133fcc86ccb2c902e2e83dbe4dcb92bae / . / docs / ReleaseNotes.html
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Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
2 "http://www.w3.org/TR/html4/strict.dtd">
3<html>
4<head>
5 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
6 <link rel="stylesheet" href="llvm.css" type="text/css">
Jeffrey Yasskin8ee1b0a2010-01-28 01:14:43 +0000[diff] [blame]7 <title>LLVM 2.7 Release Notes</title>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]8</head>
9<body>
10
Jeffrey Yasskin8ee1b0a2010-01-28 01:14:43 +0000[diff] [blame]11<div class="doc_title">LLVM 2.7 Release Notes</div>
Mikhail Glushenkov808cd3e2008-10-13 02:08:34 +0000[diff] [blame]12
Chris Lattnere5236102010-03-17 04:02:39 +0000[diff] [blame]13<img align=right src="http://llvm.org/img/DragonSmall.png"
14 width="136" height="136">
15
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]16<ol>
17 <li><a href="#intro">Introduction</a></li>
Chris Lattner78a130b2008-10-13 18:01:01 +0000[diff] [blame]18 <li><a href="#subproj">Sub-project Status Update</a></li>
Jeffrey Yasskin8ee1b0a2010-01-28 01:14:43 +0000[diff] [blame]19 <li><a href="#externalproj">External Projects Using LLVM 2.7</a></li>
20 <li><a href="#whatsnew">What's New in LLVM 2.7?</a></li>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]21 <li><a href="GettingStarted.html">Installation Instructions</a></li>
22 <li><a href="#portability">Portability and Supported Platforms</a></li>
Dan Gohman0de549c2008-10-14 16:23:02 +0000[diff] [blame]23 <li><a href="#knownproblems">Known Problems</a></li>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]24 <li><a href="#additionalinfo">Additional Information</a></li>
25</ol>
26
27<div class="doc_author">
Dan Gohman0de549c2008-10-14 16:23:02 +0000[diff] [blame]28 <p>Written by the <a href="http://llvm.org">LLVM Team</a></p>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]29</div>
30
Chris Lattner6ba1be32010-04-13 06:37:00 +0000[diff] [blame]31<!--
Jeffrey Yasskin8ee1b0a2010-01-28 01:14:43 +0000[diff] [blame]32<h1 style="color:red">These are in-progress notes for the upcoming LLVM 2.7
33release.<br>
34You may prefer the
35<a href="http://llvm.org/releases/2.6/docs/ReleaseNotes.html">LLVM 2.6
Chris Lattner6ba1be32010-04-13 06:37:00 +0000[diff] [blame]36Release Notes</a>.</h1>-->
Jeffrey Yasskin8ee1b0a2010-01-28 01:14:43 +0000[diff] [blame]37
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]38<!-- *********************************************************************** -->
39<div class="doc_section">
40 <a name="intro">Introduction</a>
41</div>
42<!-- *********************************************************************** -->
43
44<div class="doc_text">
45
Chris Lattner92eacf82008-10-13 17:57:36 +0000[diff] [blame]46<p>This document contains the release notes for the LLVM Compiler
Jeffrey Yasskin8ee1b0a2010-01-28 01:14:43 +0000[diff] [blame]47Infrastructure, release 2.7. Here we describe the status of LLVM, including
Chris Lattner92eacf82008-10-13 17:57:36 +0000[diff] [blame]48major improvements from the previous release and significant known problems.
Mikhail Glushenkovf61066a2009-03-01 18:09:47 +0000[diff] [blame]49All LLVM releases may be downloaded from the <a
Chris Lattner92eacf82008-10-13 17:57:36 +0000[diff] [blame]50href="http://llvm.org/releases/">LLVM releases web site</a>.</p>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]51
52<p>For more information about LLVM, including information about the latest
53release, please check out the <a href="http://llvm.org/">main LLVM
54web site</a>. If you have questions or comments, the <a
Chris Lattner58b1d0f2010-03-17 04:41:49 +0000[diff] [blame]55href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM Developer's
56Mailing List</a> is a good place to send them.</p>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]57
Mikhail Glushenkov808cd3e2008-10-13 02:08:34 +0000[diff] [blame]58<p>Note that if you are reading this file from a Subversion checkout or the
Chris Lattnerb0d6c502007-09-21 03:54:09 +0000[diff] [blame]59main LLVM web page, this document applies to the <i>next</i> release, not the
Gabor Greif7c65c4f2008-10-14 11:00:32 +0000[diff] [blame]60current one. To see the release notes for a specific release, please see the
Chris Lattnerb0d6c502007-09-21 03:54:09 +0000[diff] [blame]61<a href="http://llvm.org/releases/">releases page</a>.</p>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]62
63</div>
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]64
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]65
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]66<!--
67Almost dead code.
68 include/llvm/Analysis/LiveValues.h => Dan
69 lib/Transforms/IPO/MergeFunctions.cpp => consider for 2.8.
70 llvm/Analysis/PointerTracking.h => Edwin wants this, consider for 2.8.
Chris Lattner6ba1be32010-04-13 06:37:00 +0000[diff] [blame]71 ABCD, GEPSplitterPass
Chris Lattner2bd5e652010-01-16 21:25:13 +0000[diff] [blame]72 MSIL backend?
Chris Lattner2b656342010-03-17 06:41:58 +0000[diff] [blame]73 lib/Transforms/Utils/SSI.cpp -> ABCD depends on it.
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]74-->
75
76
Jeffrey Yasskin8ee1b0a2010-01-28 01:14:43 +0000[diff] [blame]77<!-- Features that need text if they're finished for 2.7:
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]78 strong phi elim
Chris Lattner6fd928d2010-04-21 05:17:40 +0000[diff] [blame^]79 llvm.dbg.value: variable debug info for optimized code
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]80 loop dependence analysis
Chris Lattner8fda4952008-02-10 07:46:44 +0000[diff] [blame]81 -->
Mikhail Glushenkov808cd3e2008-10-13 02:08:34 +0000[diff] [blame]82
Chris Lattner4f076402008-10-12 19:47:48 +0000[diff] [blame]83 <!-- for announcement email:
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]84 Logo web page.
85 llvm devmtg
86 compiler_rt
87 KLEE web page at klee.llvm.org
88 Many new papers added to /pubs/
Chris Lattner2b656342010-03-17 06:41:58 +0000[diff] [blame]89 Mention gcc plugin.
Chris Lattnera53f4972009-02-25 06:34:50 +0000[diff] [blame]90 -->
Chris Lattner8fda4952008-02-10 07:46:44 +0000[diff] [blame]91
Chris Lattner78a130b2008-10-13 18:01:01 +0000[diff] [blame]92<!-- *********************************************************************** -->
93<div class="doc_section">
94 <a name="subproj">Sub-project Status Update</a>
Chris Lattnerf65224f2008-06-08 21:34:41 +0000[diff] [blame]95</div>
Chris Lattner78a130b2008-10-13 18:01:01 +0000[diff] [blame]96<!-- *********************************************************************** -->
Chris Lattnerf65224f2008-06-08 21:34:41 +0000[diff] [blame]97
98<div class="doc_text">
Chris Lattnerf6a0d382008-06-08 21:58:17 +0000[diff] [blame]99<p>
Jeffrey Yasskin8ee1b0a2010-01-28 01:14:43 +0000[diff] [blame]100The LLVM 2.7 distribution currently consists of code from the core LLVM
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]101repository (which roughly includes the LLVM optimizers, code generators
102and supporting tools), the Clang repository and the llvm-gcc repository. In
103addition to this code, the LLVM Project includes other sub-projects that are in
104development. Here we include updates on these subprojects.
Bill Wendlingdde41b82009-03-02 04:28:57 +0000[diff] [blame]105</p>
Chris Lattner78a130b2008-10-13 18:01:01 +0000[diff] [blame]106
Chris Lattnerf6a0d382008-06-08 21:58:17 +0000[diff] [blame]107</div>
108
Chris Lattner78a130b2008-10-13 18:01:01 +0000[diff] [blame]109
Chris Lattnerf6a0d382008-06-08 21:58:17 +0000[diff] [blame]110<!--=========================================================================-->
Chris Lattner78a130b2008-10-13 18:01:01 +0000[diff] [blame]111<div class="doc_subsection">
Chris Lattnera3c683b2008-10-13 18:11:54 +0000[diff] [blame]112<a name="clang">Clang: C/C++/Objective-C Frontend Toolkit</a>
Chris Lattnerf6a0d382008-06-08 21:58:17 +0000[diff] [blame]113</div>
114
115<div class="doc_text">
116
Jeffrey Yasskin8ee1b0a2010-01-28 01:14:43 +0000[diff] [blame]117<p>The <a href="http://clang.llvm.org/">Clang project</a> is ...</p>
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]118
Jeffrey Yasskin8ee1b0a2010-01-28 01:14:43 +0000[diff] [blame]119<p>In the LLVM 2.7 time-frame, the Clang team has made many improvements:</p>
Bill Wendling385b0d32008-10-27 09:27:33 +0000[diff] [blame]120
Daniel Dunbarf3e35782008-10-14 23:25:09 +0000[diff] [blame]121<ul>
Daniel Dunbar29f1e722010-03-25 16:09:18 +0000[diff] [blame]122<li>FIXME: C++! Include a link to cxx_compatibility.html</li>
123
124<li>FIXME: Static Analyzer improvements?</li>
125
126<li>CIndex API and Python bindings: Clang now includes a C API as part of the
127CIndex library. Although we make make some changes to the API in the future, it
128is intended to be stable and has been designed for use by external projects. See
129the Clang
130doxygen <a href="http://clang.llvm.org/doxygen/group__CINDEX.html">CIndex</a>
131documentation for more details. The CIndex API also includings an preliminary
132set of Python bindings.</li>
133
134<li>ARM Support: Clang now has ABI support for both the Darwin and Linux ARM
135ABIs. Coupled with many improvements to the LLVM ARM backend, Clang is now
136suitable for use as a a beta quality ARM compiler.</li>
Bill Wendlinga8fb81d2009-03-02 04:28:18 +0000[diff] [blame]137</ul>
Chris Lattnera3c683b2008-10-13 18:11:54 +0000[diff] [blame]138</div>
139
140<!--=========================================================================-->
141<div class="doc_subsection">
142<a name="clangsa">Clang Static Analyzer</a>
143</div>
144
145<div class="doc_text">
146
Jeffrey Yasskin8ee1b0a2010-01-28 01:14:43 +0000[diff] [blame]147<p>Previously announced in the 2.4, 2.5, and 2.6 LLVM releases, the Clang project also
Ted Kremeneka0d77d72009-02-27 07:01:32 +0000[diff] [blame]148includes an early stage static source code analysis tool for <a
149href="http://clang.llvm.org/StaticAnalysis.html">automatically finding bugs</a>
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]150in C and Objective-C programs. The tool performs checks to find
Ted Kremeneka0d77d72009-02-27 07:01:32 +0000[diff] [blame]151bugs that occur on a specific path within a program.</p>
Chris Lattnerc2d84672008-10-14 00:52:49 +0000[diff] [blame]152
Chris Lattnere5236102010-03-17 04:02:39 +0000[diff] [blame]153<p>In the LLVM 2.7 time-frame, the analyzer core has sprouted legs and...</p>
Chris Lattnerf6a0d382008-06-08 21:58:17 +0000[diff] [blame]154
155</div>
156
Chris Lattner78a130b2008-10-13 18:01:01 +0000[diff] [blame]157<!--=========================================================================-->
158<div class="doc_subsection">
Nicolas Geoffray2b139382008-10-14 19:23:04 +0000[diff] [blame]159<a name="vmkit">VMKit: JVM/CLI Virtual Machine Implementation</a>
Chris Lattner78a130b2008-10-13 18:01:01 +0000[diff] [blame]160</div>
161
162<div class="doc_text">
163<p>
Nicolas Geoffray2b139382008-10-14 19:23:04 +0000[diff] [blame]164The <a href="http://vmkit.llvm.org/">VMKit project</a> is an implementation of
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]165a JVM and a CLI Virtual Machine (Microsoft .NET is an
166implementation of the CLI) using LLVM for static and just-in-time
167compilation.</p>
Chris Lattner78a130b2008-10-13 18:01:01 +0000[diff] [blame]168
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]169<p>
Chris Lattnerd5b62522010-03-29 18:34:13 +0000[diff] [blame]170With the release of LLVM 2.7, VMKit has shifted to a great framework for writing
171virtual machines. VMKit now offers precise and efficient garbage collection with
172multi-threading support, thanks to the MMTk memory management toolkit, as well
173as just in time and ahead of time compilation with LLVM. The major changes in
174VMKit 0.27 are:</p>
Chris Lattner78a130b2008-10-13 18:01:01 +0000[diff] [blame]175
Nicolas Geoffray2b139382008-10-14 19:23:04 +0000[diff] [blame]176<ul>
177
Chris Lattnerd5b62522010-03-29 18:34:13 +0000[diff] [blame]178<li>Garbage collection: VMKit now uses the MMTk toolkit for garbage collectors.
179 The first collector to be ported is the MarkSweep collector, which is precise,
180 and drastically improves the performance of VMKit.</li>
181<li>Line number information in the JVM: by using the debug metadata of LLVM, the
182 JVM now supports precise line number information, useful when printing a stack
183 trace.</li>
184<li>Interface calls in the JVM: we implemented a variant of the Interface Method
185 Table technique for interface calls in the JVM.
186</li>
Nicolas Geoffray2b139382008-10-14 19:23:04 +0000[diff] [blame]187
188</ul>
Chris Lattner78a130b2008-10-13 18:01:01 +0000[diff] [blame]189</div>
190
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]191
192<!--=========================================================================-->
193<div class="doc_subsection">
194<a name="compiler-rt">compiler-rt: Compiler Runtime Library</a>
195</div>
196
197<div class="doc_text">
198<p>
199The new LLVM <a href="http://compiler-rt.llvm.org/">compiler-rt project</a>
200is a simple library that provides an implementation of the low-level
201target-specific hooks required by code generation and other runtime components.
202For example, when compiling for a 32-bit target, converting a double to a 64-bit
203unsigned integer is compiled into a runtime call to the "__fixunsdfdi"
204function. The compiler-rt library provides highly optimized implementations of
205this and other low-level routines (some are 3x faster than the equivalent
206libgcc routines).</p>
207
208<p>
209All of the code in the compiler-rt project is available under the standard LLVM
Chris Lattner6fd928d2010-04-21 05:17:40 +0000[diff] [blame^]210License, a "BSD-style" license. New in LLVM 2.7: compiler_rt now
211supports ARM targets.</p>
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]212
213</div>
214
215<!--=========================================================================-->
216<div class="doc_subsection">
Duncan Sands2d9c3082010-04-02 09:23:15 +0000[diff] [blame]217<a name="dragonegg">DragonEgg: llvm-gcc ported to gcc-4.5</a>
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]218</div>
219
220<div class="doc_text">
221<p>
Duncan Sands2d9c3082010-04-02 09:23:15 +0000[diff] [blame]222<a href="http://dragonegg.llvm.org/">DragonEgg</a> is a port of llvm-gcc to
223gcc-4.5. Unlike llvm-gcc, which makes many intrusive changes to the underlying
224gcc-4.2 code, dragonegg in theory does not require any gcc-4.5 modifications
225whatsoever (currently one small patch is needed). This is thanks to the new
226<a href="http://gcc.gnu.org/wiki/plugins">gcc plugin architecture</a>, which
227makes it possible to modify the behaviour of gcc at runtime by loading a plugin,
228which is nothing more than a dynamic library which conforms to the gcc plugin
229interface. DragonEgg is a gcc plugin that causes the LLVM optimizers to be run
230instead of the gcc optimizers, and the LLVM code generators instead of the gcc
231code generators, just like llvm-gcc. To use it, you add
232"-fplugin=path/dragonegg.so" to the gcc-4.5 command line, and gcc-4.5 magically
233becomes llvm-gcc-4.5!
234</p>
235
236<p>
237DragonEgg is still a work in progress. Currently C works very well, while C++,
238Ada and Fortran work fairly well. All other languages either don't work at all,
239or only work poorly. For the moment only the x86-32 and x86-64 targets are
Duncan Sands566f40b2010-04-20 19:40:58 +0000[diff] [blame]240supported, and only on linux and darwin (darwin needs an additional gcc patch).
Duncan Sands2d9c3082010-04-02 09:23:15 +0000[diff] [blame]241</p>
242
243<p>
Duncan Sands566f40b2010-04-20 19:40:58 +0000[diff] [blame]244The first dragonegg release will occur shortly after llvm-2.7 is released.
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]245</p>
246
247</div>
248
249
250<!--=========================================================================-->
251<div class="doc_subsection">
252<a name="mc">llvm-mc: Machine Code Toolkit</a>
253</div>
254
255<div class="doc_text">
256<p>
Jeffrey Yasskin8ee1b0a2010-01-28 01:14:43 +0000[diff] [blame]257The LLVM Machine Code (MC) Toolkit project is ...
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]258</p>
259
260</div>
261
262
Chris Lattnerb2cc5022009-02-26 22:33:38 +0000[diff] [blame]263<!-- *********************************************************************** -->
264<div class="doc_section">
Jeffrey Yasskin8ee1b0a2010-01-28 01:14:43 +0000[diff] [blame]265 <a name="externalproj">External Open Source Projects Using LLVM 2.7</a>
Chris Lattnerb2cc5022009-02-26 22:33:38 +0000[diff] [blame]266</div>
267<!-- *********************************************************************** -->
268
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]269<div class="doc_text">
270
271<p>An exciting aspect of LLVM is that it is used as an enabling technology for
272 a lot of other language and tools projects. This section lists some of the
Jeffrey Yasskin8ee1b0a2010-01-28 01:14:43 +0000[diff] [blame]273 projects that have already been updated to work with LLVM 2.7.</p>
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]274</div>
275
Chris Lattnerb2cc5022009-02-26 22:33:38 +0000[diff] [blame]276<!--=========================================================================-->
277<div class="doc_subsection">
278<a name="pure">Pure</a>
279</div>
280
281<div class="doc_text">
282<p>
Chris Lattner47202c32009-03-02 02:37:32 +0000[diff] [blame]283<a href="http://pure-lang.googlecode.com/">Pure</a>
284is an algebraic/functional programming language based on term rewriting.
Chris Lattnerb2cc5022009-02-26 22:33:38 +0000[diff] [blame]285Programs are collections of equations which are used to evaluate expressions in
286a symbolic fashion. Pure offers dynamic typing, eager and lazy evaluation,
Mikhail Glushenkovf61066a2009-03-01 18:09:47 +0000[diff] [blame]287lexical closures, a hygienic macro system (also based on term rewriting),
Chris Lattnerb2cc5022009-02-26 22:33:38 +0000[diff] [blame]288built-in list and matrix support (including list and matrix comprehensions) and
289an easy-to-use C interface. The interpreter uses LLVM as a backend to
290 JIT-compile Pure programs to fast native code.</p>
291
Chris Lattner1f8dc512010-03-17 17:25:49 +0000[diff] [blame]292<p>Pure versions 0.43 and later have been tested and are known to work with
293LLVM 2.7 (and continue to work with older LLVM releases >= 2.5).</p>
294
Chris Lattnerb2cc5022009-02-26 22:33:38 +0000[diff] [blame]295</div>
296
Chris Lattner1ad599a2009-02-28 18:58:01 +0000[diff] [blame]297<!--=========================================================================-->
298<div class="doc_subsection">
299<a name="RoadsendPHP">Roadsend PHP</a>
300</div>
301
302<div class="doc_text">
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]303<p>
304<a href="http://code.roadsend.com/rphp">Roadsend PHP</a> (rphp) is an open
Chris Lattner9e08de12009-03-02 19:07:24 +0000[diff] [blame]305source implementation of the PHP programming
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]306language that uses LLVM for its optimizer, JIT and static compiler. This is a
Chris Lattnere5236102010-03-17 04:02:39 +0000[diff] [blame]307reimplementation of an earlier project that is now based on LLVM.
Chris Lattner1f8dc512010-03-17 17:25:49 +0000[diff] [blame]308</p>
Chris Lattner1ad599a2009-02-28 18:58:01 +0000[diff] [blame]309</div>
Chris Lattnerb2cc5022009-02-26 22:33:38 +0000[diff] [blame]310
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]311<!--=========================================================================-->
312<div class="doc_subsection">
313<a name="UnladenSwallow">Unladen Swallow</a>
314</div>
315
316<div class="doc_text">
317<p>
318<a href="http://code.google.com/p/unladen-swallow/">Unladen Swallow</a> is a
319branch of <a href="http://python.org/">Python</a> intended to be fully
320compatible and significantly faster. It uses LLVM's optimization passes and JIT
Chris Lattnerd7db82c2010-03-18 06:52:15 +0000[diff] [blame]321compiler.
Chris Lattnere5236102010-03-17 04:02:39 +0000[diff] [blame]322</p>
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]323</div>
324
325<!--=========================================================================-->
326<div class="doc_subsection">
Chris Lattner49894862010-03-29 17:50:39 +0000[diff] [blame]327<a name="tce">TTA-based Codesign Environment (TCE)</a>
328</div>
329
330<div class="doc_text">
331<p>
332<a href="http://tce.cs.tut.fi/">TCE</a> is a toolset for designing
333application-specific processors (ASP) based on the Transport triggered
334architecture (TTA). The toolset provides a complete co-design flow from C/C++
335programs down to synthesizable VHDL and parallel program binaries. Processor
336customization points include the register files, function units, supported
337operations, and the interconnection network.</p>
338
339<p>TCE uses llvm-gcc/Clang and LLVM for C/C++ language support, target
340independent optimizations and also for parts of code generation. It generates
341new LLVM-based code generators "on the fly" for the designed TTA processors and
342loads them in to the compiler backend as runtime libraries to avoid per-target
343recompilation of larger parts of the compiler chain.</p>
344
345</div>
Chris Lattnerf6a0d382008-06-08 21:58:17 +0000[diff] [blame]346
John Criswelle75f04f2010-04-06 14:52:14 +0000[diff] [blame]347<!--=========================================================================-->
348<div class="doc_subsection">
349<a name="safecode">SAFECode Compiler</a>
350</div>
351
352<div class="doc_text">
353<p>
354<a href="http://safecode.cs.illinois.edu">SAFECode</a> is a memory safe C
355compiler built using LLVM. It takes standard, unannotated C code, analyzes the
356code to ensure that memory accesses and array indexing operations are safe, and
357instruments the code with run-time checks when safety cannot be proven
358statically.
359</p>
360</div>
361
362
Chris Lattnerf6a0d382008-06-08 21:58:17 +0000[diff] [blame]363<!-- *********************************************************************** -->
364<div class="doc_section">
Jeffrey Yasskin8ee1b0a2010-01-28 01:14:43 +0000[diff] [blame]365 <a name="whatsnew">What's New in LLVM 2.7?</a>
Chris Lattnerf6a0d382008-06-08 21:58:17 +0000[diff] [blame]366</div>
367<!-- *********************************************************************** -->
368
Chris Lattner5cce7a52008-06-08 22:59:35 +0000[diff] [blame]369<div class="doc_text">
370
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]371<p>This release includes a huge number of bug fixes, performance tweaks and
Chris Lattner92eacf82008-10-13 17:57:36 +0000[diff] [blame]372minor improvements. Some of the major improvements and new features are listed
373in this section.
Chris Lattner5cce7a52008-06-08 22:59:35 +0000[diff] [blame]374</p>
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]375
Chris Lattner6fd928d2010-04-21 05:17:40 +0000[diff] [blame^]376<p>In addition to changes to the code, between LLVM 2.6 and 2.7, a number of
377organization changes have happened:
378</p>
379
380<ul>
381<li>LLVM has a new <a href="http://llvm.org/Logo.html">official Logo</a>!</li>
382
383<li><a href="http://llvm.org">llvm.org</a> is now hosted on a new (and much
384faster) server. It is still hosted as the University of Illinois.</li>
385
386<li>Ted Kremenek and Doug Gregor have stepped forward as <a
387 href="http://llvm.org/docs/DeveloperPolicy.html#owners">Code Owners</a> of the
388 Clang static analyzer and the Clang Frontend, respectively.</li>
389
390<li>The LLVM web pages are now checked into the SVN server, in the "www",
391 "www-pubs" and "www-releases" SVN modules. Previously they were hidden in a
392 largely inaccessible old CVS server.</p>
393</ul>
Chris Lattner5cce7a52008-06-08 22:59:35 +0000[diff] [blame]394</div>
395
Chris Lattnerf6a0d382008-06-08 21:58:17 +0000[diff] [blame]396<!--=========================================================================-->
Chris Lattnerf65224f2008-06-08 21:34:41 +0000[diff] [blame]397<div class="doc_subsection">
Chris Lattnere0798082008-02-06 18:00:06 +0000[diff] [blame]398<a name="majorfeatures">Major New Features</a>
399</div>
400
401<div class="doc_text">
402
Jeffrey Yasskin8ee1b0a2010-01-28 01:14:43 +0000[diff] [blame]403<p>LLVM 2.7 includes several major new capabilities:</p>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]404
405<ul>
Chris Lattner6fd928d2010-04-21 05:17:40 +0000[diff] [blame^]406<li>New MicroBlaze backend. http://en.wikipedia.org/wiki/MicroBlaze</li>
407
408<li>Extensible metadata solid.</li>
409
410<li>Debug info improvements: using metadata instead of llvm.dbg global variables.
411This brings several enhancements including improved compile times.</li>
412
413<li>Indirect branch + address of label (blog post), particularly useful for
414interpreters.</li>
415
416<li>New instruction selector.</li>
417
Chris Lattner5ba16862008-02-10 08:18:42 +0000[diff] [blame]418</ul>
Chris Lattner88b76122010-04-16 06:20:22 +0000[diff] [blame]419libllvm2.7.so?? configure with --enable-shared
Chris Lattner6fd928d2010-04-21 05:17:40 +0000[diff] [blame^]420MC encoding and disassembler apis.
421MC Disassembler (with blog post), MCInstPrinter. Many X86 backend and AsmPrinter simplifications
422Can transcode from GAS to intel syntax with "llvm-mc foo.s -output-asm-variant=1"
Chris Lattner88b76122010-04-16 06:20:22 +0000[diff] [blame]423
Chris Lattner1071dbb2010-03-29 18:39:28 +0000[diff] [blame]424
Chris Lattner2b656342010-03-17 06:41:58 +0000[diff] [blame]425
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]426</div>
427
Chris Lattnerb0d6c502007-09-21 03:54:09 +0000[diff] [blame]428<!--=========================================================================-->
429<div class="doc_subsection">
Chris Lattner47202c32009-03-02 02:37:32 +0000[diff] [blame]430<a name="coreimprovements">LLVM IR and Core Improvements</a>
Chris Lattnerc3649452008-02-10 08:17:19 +0000[diff] [blame]431</div>
432
433<div class="doc_text">
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]434<p>LLVM IR has several new features for better support of new targets and that
435expose new optimization opportunities:</p>
Chris Lattnerc3649452008-02-10 08:17:19 +0000[diff] [blame]436
Chris Lattnerc5a4e312008-06-05 06:25:56 +0000[diff] [blame]437<ul>
Chris Lattner6fd928d2010-04-21 05:17:40 +0000[diff] [blame^]438<li>New InlineHint and StackAlignment function attributes
439Half-float support in APFloat
440llvm.objectsize.
441New llvm/Support/Regex.h API. FileCheck now does regex's
442Pre-Alpha support for unions in IR.
443dbgs() and -debug-buffer-size=N
444</li>
Chris Lattnerc3649452008-02-10 08:17:19 +0000[diff] [blame]445</ul>
Mikhail Glushenkov808cd3e2008-10-13 02:08:34 +0000[diff] [blame]446
Chris Lattnerc3649452008-02-10 08:17:19 +0000[diff] [blame]447</div>
448
449<!--=========================================================================-->
450<div class="doc_subsection">
Chris Lattner8fda4952008-02-10 07:46:44 +0000[diff] [blame]451<a name="optimizer">Optimizer Improvements</a>
452</div>
453
454<div class="doc_text">
455
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]456<p>In addition to a large array of minor performance tweaks and bug fixes, this
Chris Lattnerea9c2242008-10-13 21:50:36 +0000[diff] [blame]457release includes a few major enhancements and additions to the optimizers:</p>
Chris Lattner8fda4952008-02-10 07:46:44 +0000[diff] [blame]458
459<ul>
460
Jeffrey Yasskin8ee1b0a2010-01-28 01:14:43 +0000[diff] [blame]461<li>...</li>
Chris Lattner6fd928d2010-04-21 05:17:40 +0000[diff] [blame^]462Inliner reuses arrays allocas when inlining multiple callers to reduce stack usage.
463Optimal Edge Profiling?
464Instcombine is now a library, has its own IRBuilder to simplify itself.
465Better code size analysis in loop unswitch, inliner code split out to a new
466 CodeMetrics class for reuse.
467Many changes to the pass ordering for improved optimization effectiveness.
468BasicAA improved to be less dependent on "type safe" pointers, it can now look
469 through bitcasts more aggressively.
470GVN PHI Translation improvements. blog post: http://blog.llvm.org/2009/12/advanced-topics-in-redundant-load.html
471New SCEV AA pass: -scev-aa
472Target data now has notion of 'native' integer data types which optimizations can use.
473Opt now works conservatively if no target data is set (is this fully working?)
474New Analysis/InstructionSimplify.h interface for simplifying instructions that don't exist.
475Jump threading is now much more aggressive at simplifying correlated
476 conditionals and threading blocks with otherwise complex logic. CondProp pass
477 removed (functionality merged into jump threading).
478New SSAUpdater and MachineSSAUpdater classes for unstructured ssa updating,
479 changed jump threading, GVN, etc to use it which simplified them and speed
480 them up.
481
Chris Lattner47202c32009-03-02 02:37:32 +0000[diff] [blame]482
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]483</ul>
Chris Lattner47202c32009-03-02 02:37:32 +0000[diff] [blame]484
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]485</div>
Chris Lattner47202c32009-03-02 02:37:32 +0000[diff] [blame]486
Chris Lattner47202c32009-03-02 02:37:32 +0000[diff] [blame]487
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]488<!--=========================================================================-->
489<div class="doc_subsection">
490<a name="executionengine">Interpreter and JIT Improvements</a>
491</div>
Chris Lattnerea9c2242008-10-13 21:50:36 +0000[diff] [blame]492
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]493<div class="doc_text">
494
495<ul>
Chris Lattner6fd928d2010-04-21 05:17:40 +0000[diff] [blame^]496<li>The JIT now supports generating debug information, which is compatible with
497the new GDB 7.0 (and later) interfaces for registering debug info for
498dynamically generated code.</li>
499
Jeffrey Yasskin40715142010-01-29 19:10:38 +0000[diff] [blame]500<li>The JIT now <a
501href="http://llvm.org/viewvc/llvm-project?view=rev&revision=85295">defaults
502to compiling eagerly</a> to avoid a race condition in the lazy JIT.
503Clients that still want the lazy JIT can switch it on by calling
504<tt>ExecutionEngine::DisableLazyCompilation(false)</tt>.</li>
Chris Lattner6fd928d2010-04-21 05:17:40 +0000[diff] [blame^]505
Jeffrey Yasskinc0577082010-02-11 01:07:39 +0000[diff] [blame]506<li>It is now possible to create more than one JIT instance in the same process.
507These JITs can generate machine code in parallel,
508although <a href="http://llvm.org/docs/ProgrammersManual.html#jitthreading">you
509still have to obey the other threading restrictions</a>.</li>
Chris Lattner6fd928d2010-04-21 05:17:40 +0000[diff] [blame^]510
Chris Lattner0eef6e42008-06-08 02:45:07 +0000[diff] [blame]511</ul>
512
513</div>
514
515<!--=========================================================================-->
516<div class="doc_subsection">
Chris Lattner5f393542009-03-02 03:24:11 +0000[diff] [blame]517<a name="codegen">Target Independent Code Generator Improvements</a>
Chris Lattner0eef6e42008-06-08 02:45:07 +0000[diff] [blame]518</div>
519
520<div class="doc_text">
521
Mikhail Glushenkovf61066a2009-03-01 18:09:47 +0000[diff] [blame]522<p>We have put a significant amount of work into the code generator
523infrastructure, which allows us to implement more aggressive algorithms and make
524it run faster:</p>
Chris Lattner0eef6e42008-06-08 02:45:07 +0000[diff] [blame]525
526<ul>
Chris Lattner5f393542009-03-02 03:24:11 +0000[diff] [blame]527
Chris Lattner6fd928d2010-04-21 05:17:40 +0000[diff] [blame^]528Code generator MC'ized except for debug info and EH.
529
530New CodeGen Level CSE
531Combiner-AA improvements, why not on by default?
532Pre-regalloc tail duplication
533New LSR with "full strength reduction" mode. Description?
534Codegen level OptimizeExtsPass pass, takes advantage of x86 subregs.
535Support for the GCC option -fno-schedule-insns
536non-temporal load/store
537MachineSSAUpdater.h
538X86 and XCore supports returning arbitrary return values, returning too many values is
539 supported by returning through a hidden pointer.
540verbose-asm now produces information about spill slots and loop nests
541GHC Haskell ABI / calling conv support.
542Many improvements to debug info
543
544
Jeffrey Yasskin8ee1b0a2010-01-28 01:14:43 +0000[diff] [blame]545<li>...</li>
Chris Lattnerb0d6c502007-09-21 03:54:09 +0000[diff] [blame]546</ul>
Chris Lattnerb0d6c502007-09-21 03:54:09 +0000[diff] [blame]547</div>
548
Chris Lattner47202c32009-03-02 02:37:32 +0000[diff] [blame]549<!--=========================================================================-->
550<div class="doc_subsection">
551<a name="x86">X86-32 and X86-64 Target Improvements</a>
552</div>
553
554<div class="doc_text">
555<p>New features of the X86 target include:
556</p>
557
558<ul>
Chris Lattner5f393542009-03-02 03:24:11 +0000[diff] [blame]559
Chris Lattner6fd928d2010-04-21 05:17:40 +0000[diff] [blame^]560<li>PostRA scheduler for X86?</li>
561<li>x86 sibcall / tailcall optimization in CCC mode.</li>
562<li>X86: XMM subreg modeling for extraction of the low element.</li>
Chris Lattner5f393542009-03-02 03:24:11 +0000[diff] [blame]563
Chris Lattner47202c32009-03-02 02:37:32 +0000[diff] [blame]564</ul>
565
Chris Lattner47202c32009-03-02 02:37:32 +0000[diff] [blame]566</div>
Chris Lattnerb0d6c502007-09-21 03:54:09 +0000[diff] [blame]567
568<!--=========================================================================-->
569<div class="doc_subsection">
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]570<a name="ARM">ARM Target Improvements</a>
Chris Lattner7ccc40d2009-03-01 02:30:21 +0000[diff] [blame]571</div>
572
573<div class="doc_text">
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]574<p>New features of the ARM target include:
575</p>
Chris Lattner7ccc40d2009-03-01 02:30:21 +0000[diff] [blame]576
577<ul>
Chris Lattner7ccc40d2009-03-01 02:30:21 +0000[diff] [blame]578
Chris Lattner6fd928d2010-04-21 05:17:40 +0000[diff] [blame^]579<li>complete llvm-gcc NEON support.</li>
580<li>ARM/Thumb using reg scavenging for stack object address materialization
581 (PEI).</li>
582<li>The ARM backend now has good support for ARMv4 backend (tested on StrongARM
583 hardware), previously only supported ARMv4T and newer.</li>
584<li>ARM backend generates instructions in unified assembly syntax.</li>
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]585</ul>
Chris Lattner7ccc40d2009-03-01 02:30:21 +0000[diff] [blame]586
Chris Lattner7ccc40d2009-03-01 02:30:21 +0000[diff] [blame]587
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]588</div>
Chris Lattner7ccc40d2009-03-01 02:30:21 +0000[diff] [blame]589
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]590<!--=========================================================================-->
591<div class="doc_subsection">
592<a name="OtherTarget">Other Target Specific Improvements</a>
593</div>
Chris Lattner7ccc40d2009-03-01 02:30:21 +0000[diff] [blame]594
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]595<div class="doc_text">
596<p>New features of other targets include:
597</p>
598
599<ul>
Jeffrey Yasskin8ee1b0a2010-01-28 01:14:43 +0000[diff] [blame]600<li>...</li>
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]601</ul>
602
603</div>
604
605<!--=========================================================================-->
606<div class="doc_subsection">
607<a name="newapis">New Useful APIs</a>
608</div>
609
610<div class="doc_text">
611
612<p>This release includes a number of new APIs that are used internally, which
613 may also be useful for external clients.
614</p>
615
616<ul>
Jeffrey Yasskin8ee1b0a2010-01-28 01:14:43 +0000[diff] [blame]617<li>...</li>
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]618</ul>
619
620
621</div>
622
623<!--=========================================================================-->
624<div class="doc_subsection">
625<a name="otherimprovements">Other Improvements and New Features</a>
626</div>
627
628<div class="doc_text">
629<p>Other miscellaneous features include:</p>
630
631<ul>
Chris Lattner6fd928d2010-04-21 05:17:40 +0000[diff] [blame^]632<li>LLVM command line tools now overwrite their output by default, before they
633 would only do this with -f. This makes them more convenient to use, and
634 behave more like standard unix tools.</li>
635
636<li>The opt and llc tools now autodetect whether their input is a .ll or .bc
637 file, and automatically do the right thing. This means you don't need to
638 explicitly use the llvm-as tool for most things.</li>
Chris Lattner7ccc40d2009-03-01 02:30:21 +0000[diff] [blame]639</ul>
640
641</div>
642
Chris Lattnere45f18b2008-06-05 08:02:49 +0000[diff] [blame]643
644<!--=========================================================================-->
645<div class="doc_subsection">
Chris Lattner92eacf82008-10-13 17:57:36 +0000[diff] [blame]646<a name="changes">Major Changes and Removed Features</a>
647</div>
648
649<div class="doc_text">
650
Chris Lattnercc64a322008-10-13 22:06:31 +0000[diff] [blame]651<p>If you're already an LLVM user or developer with out-of-tree changes based
Jeffrey Yasskin8ee1b0a2010-01-28 01:14:43 +0000[diff] [blame]652on LLVM 2.6, this section lists some "gotchas" that you may run into upgrading
Chris Lattnercc64a322008-10-13 22:06:31 +0000[diff] [blame]653from the previous release.</p>
Chris Lattner92eacf82008-10-13 17:57:36 +0000[diff] [blame]654
655<ul>
Chris Lattner6fd928d2010-04-21 05:17:40 +0000[diff] [blame^]656
657<li>
658The Andersen's alias analysis ("anders-aa") pass, the Predicate Simplifier
659("predsimplify") pass, the LoopVR pass, the GVNPRE pass, and the random sampling
660profiling ("rsprofiling") passes have all been removed. They were not being
661actively maintained and had substantial problems. If you are interested in
662these components, you are welcome to ressurect them from SVN, fix the
663correctness problems, and resubmit them to mainline.</li>
664
665<li>LLVM now defaults to building most libraries with RTTI turned off, providing
666a code size reduction. Packagers who are interested in building LLVM to support
667plugins that require RTTI information should build with "make REQUIRE_RTTI=1"
668and should read the new <a href="Packaging.html">Advice on Packaging LLVM</a>
669document.</li>
670
Jeffrey Yasskin260af332010-02-09 23:03:44 +0000[diff] [blame]671<li>The LLVM interpreter now defaults to <em>not</em> using <tt>libffi</tt> even
672if you have it installed. This makes it more likely that an LLVM built on one
673system will work when copied to a similar system. To use <tt>libffi</tt>,
Chris Lattner6fd928d2010-04-21 05:17:40 +0000[diff] [blame^]674configure with <tt>--enable-libffi</tt></li>.
Chris Lattnercc64a322008-10-13 22:06:31 +0000[diff] [blame]675
Chris Lattner6fd928d2010-04-21 05:17:40 +0000[diff] [blame^]676<li>Debug information uses a completely different representation, an LLVM 2.6
677.bc file should work with LLVM 2.7, but debug info won't come forward.</li>
678
679<li>The LLVM 2.6 (and earlier) "malloc" and "free" instructions got removed,
680 along with LowerAllocations pass. Now you should just use a call to the
681 malloc and free functions in libc. These calls are optimized as well as
682 the old instructions were.</li>
683</ul>
Chris Lattnercc64a322008-10-13 22:06:31 +0000[diff] [blame]684
685<p>In addition, many APIs have changed in this release. Some of the major LLVM
686API changes are:</p>
687
688<ul>
Chris Lattner6fd928d2010-04-21 05:17:40 +0000[diff] [blame^]689<li>Just about everything has been converted to use raw_ostream instead of
690 std::ostream.</li>
691<li>llvm/ADT/iterator.h has been removed, just use &lt;iterator&gt;
692 instead.</li>
693<li>The Streams.h file and "DOUT" got removed, use "DEBUG(errs() &lt;&lt; ...);"
694 instead.</li>
Jeffrey Yasskin2ca16212010-01-28 01:41:20 +0000[diff] [blame]695<li><tt>ModuleProvider</tt> has been <a
696href="http://llvm.org/viewvc/llvm-project?view=rev&revision=94686">removed</a>
697and its methods moved to <tt>Module</tt> and <tt>GlobalValue</tt>.
698Most clients can remove uses of <tt>ExistingModuleProvider</tt>,
699replace <tt>getBitcodeModuleProvider</tt> with
700<tt>getLazyBitcodeModule</tt>, and pass their <tt>Module</tt> to
701functions that used to accept <tt>ModuleProvider</tt>. Clients who
702wrote their own <tt>ModuleProvider</tt>s will need to derive from
703<tt>GVMaterializer</tt> instead and use
704<tt>Module::setMaterializer</tt> to attach it to a
705<tt>Module</tt>.</li>
706
707<li><tt>GhostLinkage</tt> has given up the ghost.
708<tt>GlobalValue</tt>s that have not yet been read from their backing
709storage have the same linkage they will have after being read in.
710Clients must replace calls to
711<tt>GlobalValue::hasNotBeenReadFromBitcode</tt> with
712<tt>GlobalValue::isMaterializable</tt>.</li>
Daniel Dunbar61f41422010-02-10 04:09:52 +0000[diff] [blame]713
Daniel Dunbar369889a2010-02-14 01:47:19 +0000[diff] [blame]714<li>The <tt>llvm/Support/DataTypes.h</tt> header has moved
715to <tt>llvm/System/DataTypes.h</tt>.</li>
716
Duncan Sandsdd29fc82010-02-17 17:20:17 +0000[diff] [blame]717<li>The <tt>isInteger</tt>, <tt>isIntOrIntVector</tt>, <tt>isFloatingPoint</tt>,
718<tt>isFPOrFPVector</tt> and <tt>isFPOrFPVector</tt> methods have been renamed
719<tt>isIntegerTy</tt>, <tt>isIntOrIntVectorTy</tt>, <tt>isFloatingPointTy</tt>,
720<tt>isFPOrFPVectorTy</tt> and <tt>isFPOrFPVectorTy</tt> respectively.</li>
Devang Patel0e3da1a2008-10-14 20:03:43 +0000[diff] [blame]721</ul>
Chris Lattner92eacf82008-10-13 17:57:36 +0000[diff] [blame]722
Chris Lattner92eacf82008-10-13 17:57:36 +0000[diff] [blame]723</div>
724
725
726
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]727<!-- *********************************************************************** -->
728<div class="doc_section">
729 <a name="portability">Portability and Supported Platforms</a>
730</div>
731<!-- *********************************************************************** -->
732
733<div class="doc_text">
734
735<p>LLVM is known to work on the following platforms:</p>
736
737<ul>
Mikhail Glushenkovf61066a2009-03-01 18:09:47 +0000[diff] [blame]738<li>Intel and AMD machines (IA32, X86-64, AMD64, EMT-64) running Red Hat
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]739 Linux, Fedora Core, FreeBSD and AuroraUX (and probably other unix-like
740 systems).</li>
Mikhail Glushenkovf61066a2009-03-01 18:09:47 +0000[diff] [blame]741<li>PowerPC and X86-based Mac OS X systems, running 10.3 and above in 32-bit
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]742 and 64-bit modes.</li>
Chris Lattnere0798082008-02-06 18:00:06 +0000[diff] [blame]743<li>Intel and AMD machines running on Win32 using MinGW libraries (native).</li>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]744<li>Intel and AMD machines running on Win32 with the Cygwin libraries (limited
745 support is available for native builds with Visual C++).</li>
Chris Lattner9235ce52009-10-16 16:30:58 +0000[diff] [blame]746<li>Sun x86 and AMD64 machines running Solaris 10, OpenSolaris 0906.</li>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]747<li>Alpha-based machines running Debian GNU/Linux.</li>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]748</ul>
749
Chris Lattnerba948522008-06-05 06:57:39 +0000[diff] [blame]750<p>The core LLVM infrastructure uses GNU autoconf to adapt itself
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]751to the machine and operating system on which it is built. However, minor
752porting may be required to get LLVM to work on new platforms. We welcome your
753portability patches and reports of successful builds or error messages.</p>
754
755</div>
756
757<!-- *********************************************************************** -->
758<div class="doc_section">
759 <a name="knownproblems">Known Problems</a>
760</div>
761<!-- *********************************************************************** -->
762
763<div class="doc_text">
764
Mikhail Glushenkovf61066a2009-03-01 18:09:47 +0000[diff] [blame]765<p>This section contains significant known problems with the LLVM system,
Chris Lattnerb1ad47c2008-11-10 05:40:34 +0000[diff] [blame]766listed by component. If you run into a problem, please check the <a
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]767href="http://llvm.org/bugs/">LLVM bug database</a> and submit a bug if
768there isn't already one.</p>
769
Chris Lattner1f8dc512010-03-17 17:25:49 +0000[diff] [blame]770<ul>
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]771<li>LLVM will not correctly compile on Solaris and/or OpenSolaris
772using the stock GCC 3.x.x series 'out the box',
Chris Lattnerc09ffd22009-11-03 21:50:09 +0000[diff] [blame]773See: <a href="GettingStarted.html#brokengcc">Broken versions of GCC and other tools</a>.
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]774However, A <a href="http://pkg.auroraux.org/GCC">Modern GCC Build</a>
775for x86/x86-64 has been made available from the third party AuroraUX Project
776that has been meticulously tested for bootstrapping LLVM &amp; Clang.</li>
777</ul>
778
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]779</div>
780
781<!-- ======================================================================= -->
782<div class="doc_subsection">
783 <a name="experimental">Experimental features included with this release</a>
784</div>
785
786<div class="doc_text">
787
788<p>The following components of this LLVM release are either untested, known to
789be broken or unreliable, or are in early development. These components should
790not be relied on, and bugs should not be filed against them, but they may be
791useful to some people. In particular, if you would like to work on one of these
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]792components, please contact us on the <a
793href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev list</a>.</p>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]794
795<ul>
Wesley Peckbe6dc822010-03-18 14:31:30 +0000[diff] [blame]796<li>The MSIL, Alpha, SPU, MIPS, PIC16, Blackfin, MSP430, SystemZ and MicroBlaze
797 backends are experimental.</li>
Bill Wendling9c7c4382009-03-02 07:54:14 +0000[diff] [blame]798<li>The <tt>llc</tt> "<tt>-filetype=asm</tt>" (the default) is the only
Chris Lattner58b1d0f2010-03-17 04:41:49 +0000[diff] [blame]799 supported value for this option. The MachO writer is experimental, and
800 works much better in mainline SVN.</li>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]801</ul>
802
803</div>
804
805<!-- ======================================================================= -->
806<div class="doc_subsection">
807 <a name="x86-be">Known problems with the X86 back-end</a>
808</div>
809
810<div class="doc_text">
811
812<ul>
Anton Korobeynikov77d15e22008-06-08 10:24:13 +0000[diff] [blame]813 <li>The X86 backend does not yet support
814 all <a href="http://llvm.org/PR879">inline assembly that uses the X86
815 floating point stack</a>. It supports the 'f' and 't' constraints, but not
816 'u'.</li>
Chris Lattnerd95b5962008-06-08 21:19:07 +0000[diff] [blame]817 <li>The X86 backend generates inefficient floating point code when configured
818 to generate code for systems that don't have SSE2.</li>
Duncan Sands8b4f3772008-06-08 19:38:43 +0000[diff] [blame]819 <li>Win64 code generation wasn't widely tested. Everything should work, but we
John Criswellaea8c752009-03-02 15:28:15 +0000[diff] [blame]820 expect small issues to happen. Also, llvm-gcc cannot build the mingw64
821 runtime currently due
Anton Korobeynikov77d15e22008-06-08 10:24:13 +0000[diff] [blame]822 to <a href="http://llvm.org/PR2255">several</a>
John Criswellaea8c752009-03-02 15:28:15 +0000[diff] [blame]823 <a href="http://llvm.org/PR2257">bugs</a> and due to lack of support for
824 the
825 'u' inline assembly constraint and for X87 floating point inline assembly.</li>
Dan Gohman3882ecb2008-06-08 23:05:11 +0000[diff] [blame]826 <li>The X86-64 backend does not yet support the LLVM IR instruction
Chris Lattner47202c32009-03-02 02:37:32 +0000[diff] [blame]827 <tt>va_arg</tt>. Currently, the llvm-gcc and front-ends support variadic
Dan Gohman3882ecb2008-06-08 23:05:11 +0000[diff] [blame]828 argument constructs on X86-64 by lowering them manually.</li>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]829</ul>
830
831</div>
832
833<!-- ======================================================================= -->
834<div class="doc_subsection">
835 <a name="ppc-be">Known problems with the PowerPC back-end</a>
836</div>
837
838<div class="doc_text">
839
840<ul>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]841<li>The Linux PPC32/ABI support needs testing for the interpreter and static
842compilation, and lacks support for debug information.</li>
843</ul>
844
845</div>
846
847<!-- ======================================================================= -->
848<div class="doc_subsection">
849 <a name="arm-be">Known problems with the ARM back-end</a>
850</div>
851
852<div class="doc_text">
853
854<ul>
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]855<li>Support for the Advanced SIMD (Neon) instruction set is still incomplete
856and not well tested. Some features may not work at all, and the code quality
857may be poor in some cases.</li>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]858<li>Thumb mode works only on ARMv6 or higher processors. On sub-ARMv6
Duncan Sands1827fa62007-09-26 15:59:54 +0000[diff] [blame]859processors, thumb programs can crash or produce wrong
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]860results (<a href="http://llvm.org/PR1388">PR1388</a>).</li>
John Criswellaea8c752009-03-02 15:28:15 +0000[diff] [blame]861<li>Compilation for ARM Linux OABI (old ABI) is supported but not fully tested.
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]862</li>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]863</ul>
864
865</div>
866
867<!-- ======================================================================= -->
868<div class="doc_subsection">
869 <a name="sparc-be">Known problems with the SPARC back-end</a>
870</div>
871
872<div class="doc_text">
873
874<ul>
John Criswellaea8c752009-03-02 15:28:15 +0000[diff] [blame]875<li>The SPARC backend only supports the 32-bit SPARC ABI (-m32); it does not
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]876 support the 64-bit SPARC ABI (-m64).</li>
877</ul>
878
879</div>
880
881<!-- ======================================================================= -->
882<div class="doc_subsection">
Bruno Cardoso Lopes62d45d72008-10-25 14:56:26 +0000[diff] [blame]883 <a name="mips-be">Known problems with the MIPS back-end</a>
884</div>
885
886<div class="doc_text">
887
888<ul>
Bruno Cardoso Lopes62d45d72008-10-25 14:56:26 +0000[diff] [blame]889<li>64-bit MIPS targets are not supported yet.</li>
890</ul>
891
892</div>
893
894<!-- ======================================================================= -->
895<div class="doc_subsection">
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]896 <a name="alpha-be">Known problems with the Alpha back-end</a>
897</div>
898
899<div class="doc_text">
900
901<ul>
902
903<li>On 21164s, some rare FP arithmetic sequences which may trap do not have the
904appropriate nops inserted to ensure restartability.</li>
905
906</ul>
907</div>
908
909<!-- ======================================================================= -->
910<div class="doc_subsection">
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]911 <a name="c-be">Known problems with the C back-end</a>
912</div>
913
914<div class="doc_text">
915
916<ul>
Chris Lattner499c07c2008-06-05 06:35:40 +0000[diff] [blame]917<li><a href="http://llvm.org/PR802">The C backend has only basic support for
918 inline assembly code</a>.</li>
Chris Lattnere0194462007-09-26 06:01:35 +0000[diff] [blame]919<li><a href="http://llvm.org/PR1658">The C backend violates the ABI of common
920 C++ programs</a>, preventing intermixing between C++ compiled by the CBE and
Gabor Greife33c5322009-03-02 12:02:51 +0000[diff] [blame]921 C++ code compiled with <tt>llc</tt> or native compilers.</li>
Duncan Sandsbd0ad6e2008-02-10 13:40:55 +0000[diff] [blame]922<li>The C backend does not support all exception handling constructs.</li>
Duncan Sandse6e264c2009-02-25 11:51:54 +0000[diff] [blame]923<li>The C backend does not support arbitrary precision integers.</li>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]924</ul>
925
926</div>
927
928
929<!-- ======================================================================= -->
930<div class="doc_subsection">
Chris Lattner58b1d0f2010-03-17 04:41:49 +0000[diff] [blame]931 <a name="c-fe">Known problems with the llvm-gcc C and C++ front-end</a>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]932</div>
933
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]934<div class="doc_text">
935
Chris Lattner499c07c2008-06-05 06:35:40 +0000[diff] [blame]936<p>The only major language feature of GCC not supported by llvm-gcc is
937 the <tt>__builtin_apply</tt> family of builtins. However, some extensions
938 are only supported on some targets. For example, trampolines are only
Duncan Sandsa73561c2008-06-08 20:18:35 +0000[diff] [blame]939 supported on some targets (these are used when you take the address of a
940 nested function).</p>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]941
Chris Lattner499c07c2008-06-05 06:35:40 +0000[diff] [blame]942<p>If you run into GCC extensions which are not supported, please let us know.
943</p>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]944
945</div>
946
947<!-- ======================================================================= -->
948<div class="doc_subsection">
Chris Lattner6c8a1b82008-10-30 03:58:13 +0000[diff] [blame]949 <a name="fortran-fe">Known problems with the llvm-gcc Fortran front-end</a>
950</div>
951
952<div class="doc_text">
Gabor Greif1fc8fbc2008-11-04 21:50:59 +0000[diff] [blame]953<ul>
Chris Lattner6c8a1b82008-10-30 03:58:13 +0000[diff] [blame]954<li>Fortran support generally works, but there are still several unresolved bugs
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]955 in <a href="http://llvm.org/bugs/">Bugzilla</a>. Please see the
956 tools/gfortran component for details.</li>
Gabor Greif1fc8fbc2008-11-04 21:50:59 +0000[diff] [blame]957</ul>
Chris Lattner6c8a1b82008-10-30 03:58:13 +0000[diff] [blame]958</div>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]959
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]960<!-- ======================================================================= -->
961<div class="doc_subsection">
Chris Lattner499c07c2008-06-05 06:35:40 +0000[diff] [blame]962 <a name="ada-fe">Known problems with the llvm-gcc Ada front-end</a>
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]963</div>
964
965<div class="doc_text">
John Criswellaea8c752009-03-02 15:28:15 +0000[diff] [blame]966The llvm-gcc 4.2 Ada compiler works fairly well; however, this is not a mature
967technology, and problems should be expected.
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]968<ul>
Duncan Sandsa73561c2008-06-08 20:18:35 +0000[diff] [blame]969<li>The Ada front-end currently only builds on X86-32. This is mainly due
John Criswellaea8c752009-03-02 15:28:15 +0000[diff] [blame]970to lack of trampoline support (pointers to nested functions) on other platforms.
971However, it <a href="http://llvm.org/PR2006">also fails to build on X86-64</a>
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]972which does support trampolines.</li>
973<li>The Ada front-end <a href="http://llvm.org/PR2007">fails to bootstrap</a>.
Duncan Sandsf73473e2009-02-25 11:59:06 +0000[diff] [blame]974This is due to lack of LLVM support for <tt>setjmp</tt>/<tt>longjmp</tt> style
975exception handling, which is used internally by the compiler.
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]976Workaround: configure with <tt>--disable-bootstrap</tt>.</li>
Duncan Sands2dbc2e82008-10-13 17:27:23 +0000[diff] [blame]977<li>The c380004, <a href="http://llvm.org/PR2010">c393010</a>
978and <a href="http://llvm.org/PR2421">cxg2021</a> ACATS tests fail
Duncan Sandsf73473e2009-02-25 11:59:06 +0000[diff] [blame]979(c380004 also fails with gcc-4.2 mainline).
980If the compiler is built with checks disabled then <a href="http://llvm.org/PR2010">c393010</a>
981causes the compiler to go into an infinite loop, using up all system memory.</li>
Duncan Sandsc2a29a02009-03-02 16:35:57 +0000[diff] [blame]982<li>Some GCC specific Ada tests continue to crash the compiler.</li>
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]983<li>The <tt>-E</tt> binder option (exception backtraces)
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]984<a href="http://llvm.org/PR1982">does not work</a> and will result in programs
Chris Lattner0b6ea7a2009-10-13 17:48:04 +0000[diff] [blame]985crashing if an exception is raised. Workaround: do not use <tt>-E</tt>.</li>
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]986<li>Only discrete types <a href="http://llvm.org/PR1981">are allowed to start
987or finish at a non-byte offset</a> in a record. Workaround: do not pack records
988or use representation clauses that result in a field of a non-discrete type
989starting or finishing in the middle of a byte.</li>
Chris Lattnerd95b5962008-06-08 21:19:07 +0000[diff] [blame]990<li>The <tt>lli</tt> interpreter <a href="http://llvm.org/PR2009">considers
991'main' as generated by the Ada binder to be invalid</a>.
992Workaround: hand edit the file to use pointers for <tt>argv</tt> and
993<tt>envp</tt> rather than integers.</li>
994<li>The <tt>-fstack-check</tt> option <a href="http://llvm.org/PR2008">is
995ignored</a>.</li>
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]996</ul>
997</div>
998
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]999<!-- *********************************************************************** -->
1000<div class="doc_section">
1001 <a name="additionalinfo">Additional Information</a>
1002</div>
1003<!-- *********************************************************************** -->
1004
1005<div class="doc_text">
1006
1007<p>A wide variety of additional information is available on the <a
1008href="http://llvm.org">LLVM web page</a>, in particular in the <a
1009href="http://llvm.org/docs/">documentation</a> section. The web page also
1010contains versions of the API documentation which is up-to-date with the
1011Subversion version of the source code.
1012You can access versions of these documents specific to this release by going
1013into the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
1014
1015<p>If you have any questions or comments about LLVM, please feel free to contact
1016us via the <a href="http://llvm.org/docs/#maillist"> mailing
1017lists</a>.</p>
1018
1019</div>
1020
1021<!-- *********************************************************************** -->
1022
1023<hr>
1024<address>
1025 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
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Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]1027 <a href="http://validator.w3.org/check/referer"><img
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Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]1029
1030 <a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br>
1031 Last modified: $Date$
1032</address>
1033
1034</body>
1035</html>