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gerrit-public.fairphone.software / toolchain / llvm-project / 9fd1e92de8e7f8d2896d11659ab201003f211913 / . / 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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4<head>
Reid Spencere4190fa2004-11-18 18:38:58 +0000[diff] [blame]5 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
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Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]7 <link rel="stylesheet" href="llvm.css" type="text/css">
Dan Gohman62af9d22010-05-03 23:51:05 +0000[diff] [blame]8 <title>LLVM 2.8 Release Notes</title>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]9</head>
10<body>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]11
Dan Gohman62af9d22010-05-03 23:51:05 +0000[diff] [blame]12<div class="doc_title">LLVM 2.8 Release Notes</div>
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]13
Chris Lattnerc871bac2010-03-17 04:02:39 +0000[diff] [blame]14<img align=right src="http://llvm.org/img/DragonSmall.png"
Gabor Greif27b166352010-04-22 10:21:43 +0000[diff] [blame]15 width="136" height="136" alt="LLVM Dragon Logo">
Chris Lattnerc871bac2010-03-17 04:02:39 +0000[diff] [blame]16
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]17<ol>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]18 <li><a href="#intro">Introduction</a></li>
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]19 <li><a href="#subproj">Sub-project Status Update</a></li>
Dan Gohman62af9d22010-05-03 23:51:05 +0000[diff] [blame]20 <li><a href="#externalproj">External Projects Using LLVM 2.8</a></li>
21 <li><a href="#whatsnew">What's New in LLVM 2.8?</a></li>
Chris Lattner77a51732004-04-30 22:17:12 +0000[diff] [blame]22 <li><a href="GettingStarted.html">Installation Instructions</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 Lattner342f9572010-09-29 05:30:03 +0000[diff] [blame]31<!--
Chris Lattner656db162010-04-22 05:41:35 +0000[diff] [blame]32<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]33release.<br>
34You may prefer the
Dan Gohman62af9d22010-05-03 23:51:05 +0000[diff] [blame]35<a href="http://llvm.org/releases/2.7/docs/ReleaseNotes.html">LLVM 2.7
36Release Notes</a>.</h1>
Chris Lattner342f9572010-09-29 05:30:03 +0000[diff] [blame]37-->
Jeffrey Yasskin0830b972010-01-28 01:14:43 +0000[diff] [blame]38
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]39<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]40<div class="doc_section">
41 <a name="intro">Introduction</a>
42</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]43<!-- *********************************************************************** -->
44
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]45<div class="doc_text">
46
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]47<p>This document contains the release notes for the LLVM Compiler
Dan Gohman3b763f42010-05-03 23:52:21 +0000[diff] [blame]48Infrastructure, release 2.8. Here we describe the status of LLVM, including
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]49major improvements from the previous release and significant known problems.
Mikhail Glushenkov25422542009-03-01 18:09:47 +0000[diff] [blame]50All LLVM releases may be downloaded from the <a
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]51href="http://llvm.org/releases/">LLVM releases web site</a>.</p>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]52
Chris Lattnerb5bb5972004-12-07 08:04:13 +0000[diff] [blame]53<p>For more information about LLVM, including information about the latest
Chris Lattnera69595e2005-10-29 07:07:09 +0000[diff] [blame]54release, please check out the <a href="http://llvm.org/">main LLVM
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]55web site</a>. If you have questions or comments, the <a
Chris Lattner0b1c9a52010-03-17 04:41:49 +0000[diff] [blame]56href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM Developer's
57Mailing List</a> is a good place to send them.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]58
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]59<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]60main LLVM web page, this document applies to the <i>next</i> release, not the
Gabor Greif355f81c2008-10-14 11:00:32 +0000[diff] [blame]61current one. To see the release notes for a specific release, please see the
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]62<a href="http://llvm.org/releases/">releases page</a>.</p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]63
64</div>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]65
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]66
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]67<!--
68Almost dead code.
69 include/llvm/Analysis/LiveValues.h => Dan
70 lib/Transforms/IPO/MergeFunctions.cpp => consider for 2.8.
Chris Lattner13ee7952010-08-28 04:09:24 +0000[diff] [blame]71 GEPSplitterPass
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]72-->
73
74
Chris Lattner342f9572010-09-29 05:30:03 +0000[diff] [blame]75<!-- Features that need text if they're finished for 2.9:
Chris Lattnera67df2d2010-04-22 06:28:20 +0000[diff] [blame]76 combiner-aa?
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]77 strong phi elim
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 Lattner342f9572010-09-29 05:30:03 +0000[diff] [blame]80 CorrelatedValuePropagation
Chris Lattner2b8a52e2008-02-10 07:46:44 +0000[diff] [blame]81 -->
Chris Lattner342f9572010-09-29 05:30:03 +0000[diff] [blame]82
83 <!-- Announcement, lldb, libc++ -->
Chris Lattner16be34d2010-09-29 07:25:03 +0000[diff] [blame]84
Chris Lattner2b8a52e2008-02-10 07:46:44 +0000[diff] [blame]85
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]86<!-- *********************************************************************** -->
87<div class="doc_section">
88 <a name="subproj">Sub-project Status Update</a>
Chris Lattner625a3d82008-06-08 21:34:41 +0000[diff] [blame]89</div>
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]90<!-- *********************************************************************** -->
Chris Lattner625a3d82008-06-08 21:34:41 +0000[diff] [blame]91
92<div class="doc_text">
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]93<p>
Dan Gohman62af9d22010-05-03 23:51:05 +0000[diff] [blame]94The LLVM 2.8 distribution currently consists of code from the core LLVM
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]95repository (which roughly includes the LLVM optimizers, code generators
96and supporting tools), the Clang repository and the llvm-gcc repository. In
97addition to this code, the LLVM Project includes other sub-projects that are in
98development. Here we include updates on these subprojects.
Bill Wendlingf170d2e2009-03-02 04:28:57 +0000[diff] [blame]99</p>
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]100
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]101</div>
102
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]103
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]104<!--=========================================================================-->
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]105<div class="doc_subsection">
Chris Lattner44c09cd2008-10-13 18:11:54 +0000[diff] [blame]106<a name="clang">Clang: C/C++/Objective-C Frontend Toolkit</a>
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]107</div>
108
109<div class="doc_text">
110
Chris Lattner5de7f6e2010-04-26 17:42:18 +0000[diff] [blame]111<p><a href="http://clang.llvm.org/">Clang</a> is an LLVM front end for the C,
112C++, and Objective-C languages. Clang aims to provide a better user experience
113through expressive diagnostics, a high level of conformance to language
114standards, fast compilation, and low memory use. Like LLVM, Clang provides a
115modular, library-based architecture that makes it suitable for creating or
116integrating with other development tools. Clang is considered a
Chris Lattner342f9572010-09-29 05:30:03 +0000[diff] [blame]117production-quality compiler for C, Objective-C, C++ and Objective-C++ on x86
118(32- and 64-bit), and for darwin-arm targets.</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>
Chris Lattner342f9572010-09-29 05:30:03 +0000[diff] [blame]123<li>Surely these guys have done something</li>
Chris Lattnerf25bc192010-09-30 16:31:33 +0000[diff] [blame]124<li>X86-64 abi improvements? Did they make it in?</li>
Bill Wendling87adbe42009-03-02 04:28:18 +0000[diff] [blame]125</ul>
Chris Lattner44c09cd2008-10-13 18:11:54 +0000[diff] [blame]126</div>
127
128<!--=========================================================================-->
129<div class="doc_subsection">
130<a name="clangsa">Clang Static Analyzer</a>
131</div>
132
133<div class="doc_text">
134
Chris Lattner2284b6a2010-04-22 06:38:11 +0000[diff] [blame]135<p>The <a href="http://clang-analyzer.llvm.org/">Clang Static Analyzer</a>
136 project is an effort to use static source code analysis techniques to
137 automatically find bugs in C and Objective-C programs (and hopefully <a
138 href="http://clang-analyzer.llvm.org/dev_cxx.html">C++ in the
139 future</a>!). The tool is very good at finding bugs that occur on specific
140 paths through code, such as on error conditions.</p>
Chris Lattnerbcffa5a2008-10-14 00:52:49 +0000[diff] [blame]141
Chris Lattner3458ab62010-09-30 00:34:43 +0000[diff] [blame]142<p>The LLVM 2.8 release fixes a number of bugs and slightly improves precision
143 over 2.7, but there are no major new features in the release.
Chris Lattner2284b6a2010-04-22 06:38:11 +0000[diff] [blame]144</p>
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]145
146</div>
147
Chris Lattnerf5cd9862008-10-13 18:01:01 +0000[diff] [blame]148<!--=========================================================================-->
149<div class="doc_subsection">
Duncan Sands92452b92010-04-02 09:23:15 +0000[diff] [blame]150<a name="dragonegg">DragonEgg: llvm-gcc ported to gcc-4.5</a>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]151</div>
152
153<div class="doc_text">
154<p>
Duncan Sands92452b92010-04-02 09:23:15 +0000[diff] [blame]155<a href="http://dragonegg.llvm.org/">DragonEgg</a> is a port of llvm-gcc to
Duncan Sands7f9a0dc2010-09-30 17:37:34 +0000[diff] [blame]156gcc-4.5. Unlike llvm-gcc, dragonegg in theory does not require any gcc-4.5
157modifications whatsoever (currently one small patch is needed) thanks to the
158new <a href="http://gcc.gnu.org/wiki/plugins">gcc plugin architecture</a>.
159DragonEgg is a gcc plugin that makes gcc-4.5 use the LLVM optimizers and code
160generators instead of gcc's, just like with llvm-gcc.
Duncan Sands92452b92010-04-02 09:23:15 +0000[diff] [blame]161</p>
162
163<p>
Duncan Sands7f9a0dc2010-09-30 17:37:34 +0000[diff] [blame]164DragonEgg is still a work in progress, but it is able to compile a lot of code,
165for example all of gcc, LLVM and clang. Currently Ada, C, C++ and Fortran work
166well, while all other languages either don't work at all or only work poorly.
167For the moment only the x86-32 and x86-64 targets are supported, and only on
168linux and darwin (darwin may need additional gcc patches).
Duncan Sands92452b92010-04-02 09:23:15 +0000[diff] [blame]169</p>
170
171<p>
Duncan Sands7f9a0dc2010-09-30 17:37:34 +0000[diff] [blame]172The 2.8 release has the following notable changes:
173<ul>
174<li>The plugin loads faster due to exporting fewer symbols.</li>
175<li>Additional vector operations such as addps256 are now supported.</li>
176<li>Ada global variables with no initial value are no longer zero initialized,
177resulting in better optimization.</li>
178<li>The '-fplugin-arg-dragonegg-enable-gcc-optzns' flag now runs all gcc
179optimizers, rather than just a handful.</li>
180<li>Fortran programs using common variables now link correctly.</li>
181<li>GNU OMP constructs no longer crash the compiler.</li>
182</ul>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]183</p>
184
185</div>
186
Chris Lattner120804a2010-10-03 23:49:06 +0000[diff] [blame]187<!--=========================================================================-->
188<div class="doc_subsection">
189<a name="vmkit">VMKit: JVM/CLI Virtual Machine Implementation</a>
190</div>
191
192<div class="doc_text">
193<p>
194The <a href="http://vmkit.llvm.org/">VMKit project</a> is an implementation of
195a Java Virtual Machine (Java VM or JVM) that uses LLVM for static and
196just-in-time compilation. As of LLVM 2.8, VMKit now supports copying garbage
197collectors, and can be configured to use MMTk's copy mark-sweep garbage
198collector. In LLVM 2.8, the VMKit .NET VM is no longer being maintained.
199</p>
200</div>
201
202<!--=========================================================================-->
203<div class="doc_subsection">
204<a name="compiler-rt">compiler-rt: Compiler Runtime Library</a>
205</div>
206
207<div class="doc_text">
208<p>
209The new LLVM <a href="http://compiler-rt.llvm.org/">compiler-rt project</a>
210is a simple library that provides an implementation of the low-level
211target-specific hooks required by code generation and other runtime components.
212For example, when compiling for a 32-bit target, converting a double to a 64-bit
213unsigned integer is compiled into a runtime call to the "__fixunsdfdi"
214function. The compiler-rt library provides highly optimized implementations of
215this and other low-level routines (some are 3x faster than the equivalent
216libgcc routines).</p>
217
218<p>
219All of the code in the compiler-rt project is available under the standard LLVM
220License, a "BSD-style" license. New in LLVM 2.8, compiler_rt now supports
221soft floating point (for targets that don't have a real floating point unit),
222and includes an extensive testsuite for the "blocks" language feature and the
223blocks runtime included in compiler_rt.</p>
224
225</div>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]226
227<!--=========================================================================-->
228<div class="doc_subsection">
Chris Lattner342f9572010-09-29 05:30:03 +0000[diff] [blame]229<a name="lldb">LLDB: Low Level Debugger</a>
230</div>
231
232<div class="doc_text">
233<p>
Chris Lattner120804a2010-10-03 23:49:06 +0000[diff] [blame]234<a href="http://lldb.llvm.org/">LLDB</a> is a brand new member of the LLVM
235umbrella of projects. LLDB is a next generation, high-performance debugger. It
236is built as a set of reusable components which highly leverage existing
237libraries in the larger LLVM Project, such as the Clang expression parser, the
238LLVM disassembler and the LLVM JIT.</p>
Chris Lattner342f9572010-09-29 05:30:03 +0000[diff] [blame]239
240<p>
Chris Lattner120804a2010-10-03 23:49:06 +0000[diff] [blame]241LLDB is in early development and not included as part of the LLVM 2.8 release,
242but is mature enough to support basic debugging scenarios on Mac OS X in C,
243Objective-C and C++. We'd really like help extending and expanding LLDB to
244support new platforms, new languages, new architectures, and new features.
Chris Lattner342f9572010-09-29 05:30:03 +0000[diff] [blame]245</p>
246
247</div>
248
249<!--=========================================================================-->
250<div class="doc_subsection">
251<a name="libc++">libc++: C++ Standard Library</a>
252</div>
253
254<div class="doc_text">
255<p>
Chris Lattner120804a2010-10-03 23:49:06 +0000[diff] [blame]256<a href="http://libc++.llvm.org/">libc++</a> is another new member of the LLVM
257family. It is an implementation of the C++ standard library, written from the
258ground up to specifically target the forthcoming C++'0X standard and focus on
259delivering great performance.</p>
Chris Lattner342f9572010-09-29 05:30:03 +0000[diff] [blame]260
261<p>
Chris Lattner120804a2010-10-03 23:49:06 +0000[diff] [blame]262As of the LLVM 2.8 release, libc++ is virtually feature complete, but would
263benefit from more testing and better integration with Clang++. It is also
264looking forward to the C++ committee finalizing the C++'0x standard.
Chris Lattner342f9572010-09-29 05:30:03 +0000[diff] [blame]265</p>
266
267</div>
268
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]269
Chris Lattner53e06f92009-02-26 22:33:38 +0000[diff] [blame]270<!-- *********************************************************************** -->
271<div class="doc_section">
Chris Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]272 <a name="externalproj">External Open Source Projects Using LLVM 2.8</a>
Chris Lattner53e06f92009-02-26 22:33:38 +0000[diff] [blame]273</div>
274<!-- *********************************************************************** -->
275
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]276<div class="doc_text">
277
278<p>An exciting aspect of LLVM is that it is used as an enabling technology for
279 a lot of other language and tools projects. This section lists some of the
Chris Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]280 projects that have already been updated to work with LLVM 2.8.</p>
Chris Lattnerdf85c892010-04-26 17:38:10 +0000[diff] [blame]281</div>
282
Chris Lattner3458ab62010-09-30 00:34:43 +0000[diff] [blame]283<!--=========================================================================-->
284<div class="doc_subsection">
285<a name="tce">TTA-based Codesign Environment (TCE)</a>
286</div>
287
288<div class="doc_text">
289<p>
290<a href="http://tce.cs.tut.fi/">TCE</a> is a toolset for designing
291application-specific processors (ASP) based on the Transport triggered
292architecture (TTA). The toolset provides a complete co-design flow from C/C++
293programs down to synthesizable VHDL and parallel program binaries. Processor
294customization points include the register files, function units, supported
295operations, and the interconnection network.</p>
296
297<p>TCE uses llvm-gcc/Clang and LLVM for C/C++ language support, target
298independent optimizations and also for parts of code generation. It generates
299new LLVM-based code generators "on the fly" for the designed TTA processors and
300loads them in to the compiler backend as runtime libraries to avoid per-target
301recompilation of larger parts of the compiler chain.</p>
302
303</div>
304
305<!--=========================================================================-->
306<div class="doc_subsection">
307<a name="Horizon">Horizon Bytecode Compiler</a>
308</div>
309
310<div class="doc_text">
311<p>
312<a href="http://www.quokforge.org/projects/horizon">Horizon</a> is a bytecode
313language and compiler written on top of LLVM, intended for producing
314single-address-space managed code operating systems that
315run faster than the equivalent multiple-address-space C systems.
316More in-depth blurb is available on <a
317href="http://www.quokforge.org/projects/horizon/wiki/Wiki">the wiki</a>.</p>
318
319</div>
320
321<!--=========================================================================-->
322<div class="doc_subsection">
323<a name="clamav">Clam AntiVirus</a>
324</div>
325
326<div class="doc_text">
327<p>
328<a href=http://www.clamav.net>Clam AntiVirus</a> is an open source (GPL)
329anti-virus toolkit for UNIX, designed especially for e-mail scanning on mail
330gateways. Since version 0.96 it has <a
331href="http://vrt-sourcefire.blogspot.com/2010/09/introduction-to-clamavs-low-level.html">bytecode
332signatures</a> that allow writing detections for complex malware. It
333uses LLVM's JIT to speed up the execution of bytecode on
334X86,X86-64,PPC32/64, falling back to its own interpreter otherwise.
335The git version was updated to work with LLVM 2.8
336</p>
337
338<p>The <a
339href="http://git.clamav.net/gitweb?p=clamav-bytecode-compiler.git;a=blob_plain;f=docs/user/clambc-user.pdf">
340ClamAV bytecode compiler</a> uses Clang and LLVM to compile a C-like
341language, insert runtime checks, and generate ClamAV bytecode.</p>
342
343</div>
344
345<!--=========================================================================-->
346<div class="doc_subsection">
347<a name="pure">Pure</a>
348</div>
349
350<div class="doc_text">
351<p>
352<a href="http://pure-lang.googlecode.com/">Pure</a>
353is an algebraic/functional
354programming language based on term rewriting. Programs are collections
355of equations which are used to evaluate expressions in a symbolic
356fashion. Pure offers dynamic typing, eager and lazy evaluation, lexical
357closures, a hygienic macro system (also based on term rewriting),
358built-in list and matrix support (including list and matrix
359comprehensions) and an easy-to-use C interface. The interpreter uses
360LLVM as a backend to JIT-compile Pure programs to fast native code.</p>
361
362<p>Pure versions 0.44 and later have been tested and are known to work with
363LLVM 2.8 (and continue to work with older LLVM releases >= 2.5).</p>
364
365</div>
366
367<!--=========================================================================-->
368<div class="doc_subsection">
369<a name="GHC">Glasgow Haskell Compiler (GHC)</a>
370</div>
371
372<div class="doc_text">
373<p>
374<a href="http://www.haskell.org/ghc/">GHC</a> is an open source,
375state-of-the-art programming suite for
376Haskell, a standard lazy functional programming language. It includes
377an optimizing static compiler generating good code for a variety of
378platforms, together with an interactive system for convenient, quick
379development.</p>
380
381<p>In addition to the existing C and native code generators, GHC 7.0 now
382supports an <a
383href="http://hackage.haskell.org/trac/ghc/wiki/Commentary/Compiler/Backends/LLVM">LLVM
384code generator</a>. GHC supports LLVM 2.7 and later.</p>
385
386</div>
387
388<!--=========================================================================-->
389<div class="doc_subsection">
390<a name="Clay">Clay Programming Language</a>
391</div>
392
393<div class="doc_text">
394<p>
Chris Lattner510a81a2010-09-30 01:12:09 +0000[diff] [blame]395<a href="http://tachyon.in/clay/">Clay</a> is a new systems programming
Chris Lattner3458ab62010-09-30 00:34:43 +0000[diff] [blame]396language that is specifically designed for generic programming. It makes
397generic programming very concise thanks to whole program type propagation. It
398uses LLVM as its backend.</p>
399
400</div>
Chris Lattner64694df2010-04-22 21:34:16 +0000[diff] [blame]401
Chris Lattnerca7c8962010-10-01 06:34:49 +0000[diff] [blame]402<!--=========================================================================-->
403<div class="doc_subsection">
404<a name="llvm-py">llvm-py Python Bindings for LLVM</a>
405</div>
406
407<div class="doc_text">
408<p>
409<a href="http://www.mdevan.org/llvm-py/">llvm-py</a> has been updated to work
410with LLVM 2.8. llvm-py provides Python bindings for LLVM, allowing you to write a
411compiler backend or a VM in Python.</p>
412
413</div>
414
415
Chris Lattnerd93b4af2010-10-03 23:09:03 +0000[diff] [blame]416<!--=========================================================================-->
417<div class="doc_subsection">
418<a name="FAUST">FAUST Real-Time Audio Signal Processing Language</a>
419</div>
420
421<div class="doc_text">
422<p>
423<a href="http://faust.grame.fr">FAUST</a> is a compiled language for real-time
424audio signal processing. The name FAUST stands for Functional AUdio STream. Its
425programming model combines two approaches: functional programming and block
426diagram composition. In addition with the C, C++, JAVA output formats, the
427Faust compiler can now generate LLVM bitcode, and works with LLVM 2.7 and
4282.8.</p>
429
430</div>
431
432<!--=========================================================================-->
433<div class="doc_subsection">
434<a name="jade">Jade Just-in-time Adaptive Decoder Engine</a>
435</div>
436
437<div class="doc_text">
438<p><a
439href="http://sourceforge.net/apps/trac/orcc/wiki/JadeDocumentation">Jade</a>
440(Just-in-time Adaptive Decoder Engine) is a generic video decoder engine using
441LLVM for just-in-time compilation of video decoder configurations. Those
442configurations are designed by MPEG Reconfigurable Video Coding (RVC) committee.
443MPEG RVC standard is built on a stream-based dataflow representation of
444decoders. It is composed of a standard library of coding tools written in
445RVC-CAL language and a dataflow configuration &emdash; block diagram &emdash;
446of a decoder.</p>
447
448<p>Jade project is hosted as part of the <a href="http://orcc.sf.net">Open
449RVC-CAL Compiler</a> and requires it to translate the RVC-CAL standard library
450of video coding tools into an LLVM assembly code.</p>
451
452</div>
453
454<!--=========================================================================-->
455<div class="doc_subsection">
456<a name="neko_llvm_jit">LLVM JIT for Neko VM</a>
457</div>
458
459<div class="doc_text">
460<p><a href="http://github.com/vava/neko_llvm_jit">Neko LLVM JIT</a>
461replaces the standard Neko JIT with an LLVM-based implementation. While not
462fully complete, it is already providing a 1.5x speedup on 64-bit systems.
463Neko LLVM JIT requires LLVM 2.8 or later.</p>
464
465</div>
466
467<!--=========================================================================-->
468<div class="doc_subsection">
469<a name="crack">Crack Scripting Language</a>
470</div>
471
472<div class="doc_text">
473<p>
474<a href="http://code.google.com/p/crack-language/">Crack</a> aims to provide
475the ease of development of a scripting language with the performance of a
476compiled language. The language derives concepts from C++, Java and Python,
477incorporating object-oriented programming, operator overloading and strong
478typing. Crack 0.2 works with LLVM 2.7, and the forthcoming Crack 0.2.1 release
479builds on LLVM 2.8.</p>
480
481</div>
482
483<!--=========================================================================-->
484<div class="doc_subsection">
485<a name="DresdenTM">Dresden TM Compiler (DTMC)</a>
486</div>
487
488<div class="doc_text">
489<p>
490<a href="http://tm.inf.tu-dresden.de">DTMC</a> provides support for
491Transactional Memory, which is an easy-to-use and efficient way to synchronize
492accesses to shared memory. Transactions can contain normal C/C++ code (e.g.,
493__transaction { list.remove(x); x.refCount--; }) and will be executed
494virtually atomically and isolated from other transactions.</p>
495
496</div>
497
498<!--=========================================================================-->
499<div class="doc_subsection">
500<a name="Kai">Kai Interpreter</a>
501</div>
502
503<div class="doc_text">
504<p>
505<a href="http://www.oriontransfer.co.nz/research/kai">Kai</a> (Japanese 会 for
506meeting/gathering) is an experimental interpreter that provides a highly
507extensible runtime environment and explicit control over the compilation
508process. Programs are defined using nested symbolic expressions, which are all
509parsed into first-class values with minimal intrinsic semantics. Kai can
510generate optimised code at run-time (using LLVM) in order to exploit the nature
511of the underlying hardware and to integrate with external software libraries.
512It is a unique exploration into world of dynamic code compilation, and the
513interaction between high level and low level semantics.</p>
514
515</div>
516
Chris Lattner120804a2010-10-03 23:49:06 +0000[diff] [blame]517<!--=========================================================================-->
518<div class="doc_subsection">
519<a name="OSL">OSL: Open Shading Language</a>
520</div>
521
522<div class="doc_text">
523<p>
524<a href="http://code.google.com/p/openshadinglanguage/">OSL</a> is a shading
525language designed for use in physically based renderers and in particular
526production rendering. By using LLVM instead of the interpreter, it was able to
527meet its performance goals (&gt;= C-code) while retaining the benefits of
528runtime specialization and a portable high-level language.
529</p>
530
531</div>
532
533
Chris Lattnerca7c8962010-10-01 06:34:49 +0000[diff] [blame]534
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]535<!-- *********************************************************************** -->
536<div class="doc_section">
Chris Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]537 <a name="whatsnew">What's New in LLVM 2.8?</a>
Chris Lattnerc75fd522008-06-08 21:58:17 +0000[diff] [blame]538</div>
539<!-- *********************************************************************** -->
540
Chris Lattnerb7bc2aa2008-06-08 22:59:35 +0000[diff] [blame]541<div class="doc_text">
542
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]543<p>This release includes a huge number of bug fixes, performance tweaks and
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]544minor improvements. Some of the major improvements and new features are listed
545in this section.
Chris Lattnerb7bc2aa2008-06-08 22:59:35 +0000[diff] [blame]546</p>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]547
Chris Lattnera67df2d2010-04-22 06:28:20 +0000[diff] [blame]548</div>
549
550<!--=========================================================================-->
551<div class="doc_subsection">
Chris Lattnercdc44ed2008-02-06 18:00:06 +0000[diff] [blame]552<a name="majorfeatures">Major New Features</a>
553</div>
554
555<div class="doc_text">
556
Chris Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]557<p>LLVM 2.8 includes several major new capabilities:</p>
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]558
559<ul>
Chris Lattnerfcc65a72010-10-04 02:42:39 +0000[diff] [blame]560<li>As mentioned above, <a href="#libc++">libc++</a> and <a
561 href="#lldb">LLDB</a> are major new additions to the LLVM collective.</li>
562<li>LLVM 2.8 now has pretty decent support for debugging optimized code. You
563 should be able to reliably get debug info for function arguments, assuming
564 that the value is actually available where you have stopped.</li>
565</ul>
566<li>A new 'llvm-diff' tool is available that does a semantic diff of .ll
567 files.</li>
568<li>The <a href="#mc">MC subproject</a> has made major progress in this release.
569 Direct .o file writing support for darwin/x86[-64] is now reliable and
570 support for other targets and object file formats are in progress.</li>
Chris Lattner458e79f2008-02-10 08:18:42 +0000[diff] [blame]571</ul>
Chris Lattner10a3cc42010-03-17 06:41:58 +0000[diff] [blame]572
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]573</div>
574
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]575<!--=========================================================================-->
576<div class="doc_subsection">
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]577<a name="coreimprovements">LLVM IR and Core Improvements</a>
Chris Lattnerdd6acc02008-02-10 08:17:19 +0000[diff] [blame]578</div>
579
580<div class="doc_text">
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]581<p>LLVM IR has several new features for better support of new targets and that
582expose new optimization opportunities:</p>
Chris Lattnerdd6acc02008-02-10 08:17:19 +0000[diff] [blame]583
Chris Lattnerb7112222008-06-05 06:25:56 +0000[diff] [blame]584<ul>
Chris Lattnerfcc65a72010-10-04 02:42:39 +0000[diff] [blame]585<li>The <a href="LangRef.html#int_libc">memcpy, memmove, and memset</a>
586 intrinsics now take address space qualified pointers and a bit to indicate
587 whether the transfer is "<a href="LangRef.html#volatile">volatile</a>" or not.
588</li>
589<li>Per-instruction debug info metadata is much faster and uses less memory by
590 using the new DebugLoc class.</li>
591<li>LLVM IR now has a more formalized concept of "<a
592 href="LangRef.html#trapvalues">trap values</a>", which allow the optimizer
593 to optimize more aggressively in the presence of undefined behavior, while
594 still producing predictable results.</li>
595<li>LLVM IR now supports two new <a href="LangRef.html#linkage">linkage
596 types</a> (linker_private_weak and linker_private_weak_def_auto) which map
597 onto some obscure MachO concepts.</li>
Chris Lattnerdd6acc02008-02-10 08:17:19 +0000[diff] [blame]598</ul>
Mikhail Glushenkov024f7cf2008-10-13 02:08:34 +0000[diff] [blame]599
Chris Lattnerdd6acc02008-02-10 08:17:19 +0000[diff] [blame]600</div>
601
602<!--=========================================================================-->
603<div class="doc_subsection">
Chris Lattner2b8a52e2008-02-10 07:46:44 +0000[diff] [blame]604<a name="optimizer">Optimizer Improvements</a>
605</div>
606
607<div class="doc_text">
608
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]609<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]610release includes a few major enhancements and additions to the optimizers:</p>
Chris Lattner2b8a52e2008-02-10 07:46:44 +0000[diff] [blame]611
612<ul>
Chris Lattnerfcc65a72010-10-04 02:42:39 +0000[diff] [blame]613<li>As mentioned above, the optimizer now has support for updating debug
614 information as it goes. A key aspect of this is the new <a
615 href="SourceLevelDebugging.html#format_common_value">llvm.dbg.value</a>
616 intrinsic. This intrinsic represents debug info for variables that are
617 promoted to SSA values (typically by mem2reg or the -scalarrepl passes).</li>
Chris Lattner2b8a52e2008-02-10 07:46:44 +0000[diff] [blame]618
Chris Lattnerfcc65a72010-10-04 02:42:39 +0000[diff] [blame]619<li>The JumpThreading pass is now much more aggressive about implied value
620 relations, allowing it to thread conditions like "a == 4" when a is known to
621 be 13 in one of the predecessors of a block. It does this in conjunction
622 with the new LazyValueInfo analysis pass.</li>
623<li>The new RegionInfo analysis pass identifies single-entry single-exit regions
624 in the CFG. You can play with it with the "opt -regions analyze" or
625 "opt -view-regions" commands.</li>
626<li>The loop optimizer has significantly improve strength reduction and analysis
627 capabilities. Notably it is able to build on the trap value and signed
628 integer overflow information to optimize &lt;= and &gt;= loops.</li>
629<li>The CallGraphSCCPassManager now has some basic support for iterating within
630 an SCC when a optimizer devirtualizes a function call. This allows inlining
631 through indirect call sites that are devirtualized by store-load forwarding
632 and other optimizations.</li>
633<li>The new <A href="Passes.html#loweratomic">-loweratomic</a> pass is available
634 to lower atomic instructions into their non-atomic form. This can be useful
635 to optimize generic code that expects to run in a single-threaded
636 environment.</li>
637</ul>
638
639<!--
640<p>In addition to these features that are done in 2.8, there is preliminary
641 support in the release for Type Based Alias Analysis
Chris Lattnerbf1cf672010-10-02 21:59:30 +0000[diff] [blame]642 Preliminary work on TBAA but not usable in 2.8.
643 New CorrelatedValuePropagation pass, not on by default in 2.8 yet.
Chris Lattnerfcc65a72010-10-04 02:42:39 +0000[diff] [blame]644-->
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]645
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]646</div>
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]647
Chris Lattner7795ea92008-06-08 02:45:07 +0000[diff] [blame]648<!--=========================================================================-->
649<div class="doc_subsection">
Chris Lattnerf25bc192010-09-30 16:31:33 +0000[diff] [blame]650<a name="mc">MC Level Improvements</a>
651</div>
652
653<div class="doc_text">
654<p>
Chris Lattnerbf1cf672010-10-02 21:59:30 +0000[diff] [blame]655The LLVM Machine Code (aka MC) subsystem was created to solve a number
Chris Lattnerf25bc192010-09-30 16:31:33 +0000[diff] [blame]656of problems in the realm of assembly, disassembly, object file format handling,
657and a number of other related areas that CPU instruction-set level tools work
Chris Lattnerbf1cf672010-10-02 21:59:30 +0000[diff] [blame]658in.</p>
659
660<p>The MC subproject has made great leaps in LLVM 2.8. For example, support for
661 directly writing .o files from LLC (and clang) now works reliably for
662 darwin/x86[-64] (including inline assembly support) and the integrated
663 assembler is turned on by default in Clang for these targets. This provides
664 improved compile times among other things.</p>
665
666<ul>
667<li>The entire compiler has converted over to using the MCStreamer assembler API
668 instead of writing out a .s file textually.</li>
669<li>The "assembler parser" is far more mature than in 2.7, supporting a full
670 complement of directives, now supports assembler macros, etc.</li>
671<li>The "assembler backend" has been completed, including support for relaxation
672 relocation processing and all the other things that an assembler does.</li>
673<li>The MachO file format support is now fully functional and works.</li>
674<li>The MC disassembler now fully supports ARM and Thumb. ARM assembler support
675 is still in early development though.</li>
676<li>The X86 MC assembler now supports the X86 AES and AVX instruction set.</li>
Chris Lattner9fd1e922010-10-04 03:58:12 +0000[diff] [blame^]677<li>Work on ELF and COFF object files and ARM target support is well underway,
678 but isn't useful yet in LLVM 2.8. Please contact the llvmdev mailing list
679 if you're interested in this.</li>
Chris Lattnerbf1cf672010-10-02 21:59:30 +0000[diff] [blame]680</ul>
681
682<p>For more information, please see the <a
Chris Lattnerf25bc192010-09-30 16:31:33 +0000[diff] [blame]683href="http://blog.llvm.org/2010/04/intro-to-llvm-mc-project.html">Intro to the
684LLVM MC Project Blog Post</a>.
685</p>
686
Chris Lattnerf25bc192010-09-30 16:31:33 +0000[diff] [blame]687</div>
688
689
Chris Lattnerf25bc192010-09-30 16:31:33 +0000[diff] [blame]690<!--=========================================================================-->
691<div class="doc_subsection">
Chris Lattnerd434bfb2009-03-02 03:24:11 +0000[diff] [blame]692<a name="codegen">Target Independent Code Generator Improvements</a>
Chris Lattner7795ea92008-06-08 02:45:07 +0000[diff] [blame]693</div>
694
695<div class="doc_text">
696
Mikhail Glushenkov25422542009-03-01 18:09:47 +0000[diff] [blame]697<p>We have put a significant amount of work into the code generator
698infrastructure, which allows us to implement more aggressive algorithms and make
699it run faster:</p>
Chris Lattner7795ea92008-06-08 02:45:07 +0000[diff] [blame]700
701<ul>
Chris Lattner9fd1e922010-10-04 03:58:12 +0000[diff] [blame^]702<li>The clang/gcc -momit-leaf-frame-pointer argument is now supported.</li>
703<li>The clang/gcc -ffunction-sections and -fdata-sections arguments are now
704 supported on ELF targets (like GCC).</li>
705<li>The MachineCSE pass is now tuned and on by default. It eliminates common
706 subexpressions that are exposed when lowering to machine instructions.</li>
707<li>The "local" register allocator was replaced by a new "fast" register
708 allocator. This new allocator (which is often used at -O0) is substantially
709 faster and produces better code than the old local register allocator.</li>
710<li>A new LLC "-regalloc=default" option is available, which automatically
711 chooses a register allocator based on the -O optimization level.</li>
712<li>The common code generator code was modified to promote illegal argument and
713 return value vectors to wider ones when possible instead of scalarizing
714 them. For example, &lt;3 x float&gt; will now pass in one SSE register
715 instead of 3 on X86. This generates substantially better code since the
716 rest of the code generator was already expecting this.</li>
717<li>The code generator uses a new "COPY" machine instruction. This speeds up
718 the code generator and eliminates the need for targets to implement the
719 isMoveInstr hook. Also, the copyRegToReg hook was renamed to copyPhysReg
720 and simplified.</li>
721<li>The code generator now has a "LocalStackSlotPass", which optimizes stack
722 slot access for targets (like ARM) that have limited stack displacement
723 addressing.</li>
724<li>A new "PeepholeOptimizer" is available, which eliminates sign and zero
725 extends, and optimizes away compare instructions when the condition result
726 is available from a previous instruction.</li>
727<li>Atomic operations now get legalized into simpler atomic operations if not
728 natively supported, easy the implementation burden on targets.</li>
729<li>The bottom-up pre-allocation scheduler is now register pressure aware,
730 allowing it to avoid overscheduling in high pressure situations while still
731 aggressively scheduling when registers are available.</li>
732<li>A new instruction-level-parallelism pre-allocation scheduler is available,
733 which is also register pressure aware. This scheduler has shown substantial
734 wins on X86-64 and is on by default.</li>
735<li>The tblgen type inference algorithm was rewritten to be more consistent and
736 diagnose more target bugs. If you have an out-of-tree backend, you may
737 find that it finds bugs in your target description. This support also
738 allows limited support for writing patterns for instructions that return
739 multiple results (e.g. a virtual register and a flag result). The
740 'parallel' modifier in tblgen was removed, you should use the new support
741 for multiple results instead.</li>
742<li>A new (experimental) "-rendermf" pass is available which renders a
743 MachineFunction into HTML, showing live ranges and other useful
744 details.</li>
Chris Lattnerbf1cf672010-10-02 21:59:30 +0000[diff] [blame]745
Chris Lattner9fd1e922010-10-04 03:58:12 +0000[diff] [blame^]746<!--New SubRegIndex tblgen class for targets -> jakob -->
747<!-- SplitKit -->
Chris Lattnerbf1cf672010-10-02 21:59:30 +0000[diff] [blame]748
Chris Lattner9fd1e922010-10-04 03:58:12 +0000[diff] [blame^]749<li>The -fast-isel instruction selection path (used at -O0 on X86) was rewritten
750 to work bottom-up on basic blocks instead of top down. This makes it
751 slightly faster (because the MachineDCE pass is not needed any longer) and
752 allows it to generate better code in some cases.</li>
Chris Lattnerbf1cf672010-10-02 21:59:30 +0000[diff] [blame]753
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]754</ul>
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]755</div>
756
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]757<!--=========================================================================-->
758<div class="doc_subsection">
759<a name="x86">X86-32 and X86-64 Target Improvements</a>
760</div>
761
762<div class="doc_text">
763<p>New features of the X86 target include:
764</p>
765
766<ul>
Chris Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]767<li>The X86 backend now supports holding X87 floating point stack values
768 in registers across basic blocks, dramatically improving performance of code
769 that uses long double, and when targetting CPUs that don't support SSE.</li>
Chris Lattnerd434bfb2009-03-02 03:24:11 +0000[diff] [blame]770
Chris Lattnerbf1cf672010-10-02 21:59:30 +0000[diff] [blame]771 New SSEDomainFix pass:
772 On Nehalem and newer CPUs there is a 2 cycle latency penalty on using a
773 register in a different domain than where it was defined. Some instructions
774 have equvivalents for different domains, like por/orps/orpd. The
775 SSEDomainFix pass tries to minimize the number of domain crossings by
776 changing between equvivalent opcodes where possible.
777
778 X86 backend attempts to promote 16-bit integer operations to 32-bits to avoid
779 0x66 prefixes, which are slow on some microarchitectures and bloat the code
780 on others.
781
782 New support for X86 "thiscall" calling convention (x86_thiscallcc in IR) for windows.
783
784 New llvm.x86.int intrinsic (for int $42 and int3)
785
786 Verbose assembly decodes X86 shuffle instructions, e.g.:
787 insertps $113, %xmm3, %xmm0 ## xmm0 = zero,xmm0[1,2],xmm3[1]
788 unpcklps %xmm1, %xmm0 ## xmm0 = xmm0[0],xmm1[0],xmm0[1],xmm1[1]
789 pshufd $1, %xmm1, %xmm1 ## xmm1 = xmm1[1,0,0,0]
790
791 X86 ABI: <2 x float> in IR no longer maps onto MMX, it turns into <4 x float>
792
793 new GHC calling convention
794
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]795</ul>
796
Chris Lattnerd1094e02009-03-02 02:37:32 +0000[diff] [blame]797</div>
Chris Lattner0a1fd102007-09-21 03:54:09 +0000[diff] [blame]798
799<!--=========================================================================-->
800<div class="doc_subsection">
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]801<a name="ARM">ARM Target Improvements</a>
Chris Lattnerc92d7692009-03-01 02:30:21 +0000[diff] [blame]802</div>
803
804<div class="doc_text">
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]805<p>New features of the ARM target include:
806</p>
Chris Lattnerc92d7692009-03-01 02:30:21 +0000[diff] [blame]807
808<ul>
Chris Lattnerc92d7692009-03-01 02:30:21 +0000[diff] [blame]809
Chris Lattnerbf1cf672010-10-02 21:59:30 +0000[diff] [blame]810 NEON: Better performance for QQQQ (4-consecutive Q register) instructions. New reg sequence abstraction?
811 ARM: Better scheduling (list-hybrid, hybrid?)
812 ARM: Tail call support.
813 ARM: General performance work and tuning.
814
815 ARM: Half float support through intrinsics LangRef.html#int_fp16
816<li>ARMGlobalMerge: <!-- Anton --> </li>
817
Chris Lattner743bc472010-10-02 22:44:15 +0000[diff] [blame]818<li>The ARM NEON intrinsics have been substantially reworked to reduce
819 redundancy and improve code generation. Some of the major changes are:
820 <ol>
821 <li>
822 All of the NEON load and store intrinsics (llvm.arm.neon.vld* and
823 llvm.arm.neon.vst*) take an extra parameter to specify the alignment in bytes
824 of the memory being accessed.
825 </li>
826 <li>
827 The llvm.arm.neon.vaba intrinsic (vector absolute difference and
828 accumulate) has been removed. This operation is now represented using
829 the llvm.arm.neon.vabd intrinsic (vector absolute difference) followed by a
830 vector add.
831 </li>
832 <li>
833 The llvm.arm.neon.vabdl and llvm.arm.neon.vabal intrinsics (lengthening
834 vector absolute difference with and without accumlation) have been removed.
835 They are represented using the llvm.arm.neon.vabd intrinsic (vector absolute
836 difference) followed by a vector zero-extend operation, and for vabal,
837 a vector add.
838 </li>
839 <li>
840 The llvm.arm.neon.vmovn intrinsic has been removed. Calls of this intrinsic
841 are now replaced by vector truncate operations.
842 </li>
843 <li>
844 The llvm.arm.neon.vmovls and llvm.arm.neon.vmovlu intrinsics have been
845 removed. They are now represented as vector sign-extend (vmovls) and
846 zero-extend (vmovlu) operations.
847 </li>
848 <li>
849 The llvm.arm.neon.vaddl*, llvm.arm.neon.vaddw*, llvm.arm.neon.vsubl*, and
850 llvm.arm.neon.vsubw* intrinsics (lengthening vector add and subtract) have
851 been removed. They are replaced by vector add and vector subtract operations
852 where one (vaddw, vsubw) or both (vaddl, vsubl) of the operands are either
853 sign-extended or zero-extended.
854 </li>
855 <li>
856 The llvm.arm.neon.vmulls, llvm.arm.neon.vmullu, llvm.arm.neon.vmlal*, and
857 llvm.arm.neon.vmlsl* intrinsics (lengthening vector multiply with and without
858 accumulation and subtraction) have been removed. These operations are now
859 represented as vector multiplications where the operands are either
860 sign-extended or zero-extended, followed by a vector add for vmlal or a
861 vector subtract for vmlsl. Note that the polynomial vector multiply
862 intrinsic, llvm.arm.neon.vmullp, remains unchanged.
863 </li>
864 </ol>
Bob Wilson46d65802010-09-13 17:37:55 +0000[diff] [blame]865</li>
Bob Wilsone44f2982010-09-13 17:39:35 +0000[diff] [blame]866</ul>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]867</div>
Chris Lattnerc92d7692009-03-01 02:30:21 +0000[diff] [blame]868
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]869<!--=========================================================================-->
870<div class="doc_subsection">
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]871<a name="otherimprovements">Other Improvements and New Features</a>
872</div>
873
874<div class="doc_text">
875<p>Other miscellaneous features include:</p>
876
877<ul>
Chris Lattnerb3fa6bf2010-07-21 15:57:40 +0000[diff] [blame]878<li></li>
Chris Lattnerc92d7692009-03-01 02:30:21 +0000[diff] [blame]879</ul>
880
881</div>
882
Chris Lattner6cb64032008-06-05 08:02:49 +0000[diff] [blame]883
884<!--=========================================================================-->
885<div class="doc_subsection">
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]886<a name="changes">Major Changes and Removed Features</a>
887</div>
888
889<div class="doc_text">
890
Chris Lattner934e2d42008-10-13 22:06:31 +0000[diff] [blame]891<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]892on LLVM 2.7, this section lists some "gotchas" that you may run into upgrading
Chris Lattner934e2d42008-10-13 22:06:31 +0000[diff] [blame]893from the previous release.</p>
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]894
895<ul>
Chris Lattnera7f45cf2010-10-04 01:29:06 +0000[diff] [blame]896<li>The build configuration machinery changed the output directory names. It
897 wasn't clear to many people that "Release-Asserts" build was a release build
898 without asserts. To make this more clear, "Release" does not include
899 assertions and "Release+Asserts" does (likewise, "Debug" and
900 "Debug+Asserts").</li>
901<li>The MSIL Backend was removed, it was unsupported and broken.</li>
902<li>The ABCD, SSI, and SCCVN passes were removed. These were not fully
903 functional and their behavior has been or will be subsumed by the
904 LazyValueInfo pass.</li>
905<li>The LLVM IR 'Union' feature was removed. While this is a desirable feature
906 for LLVM IR to support, the existing implementation was half baked and
907 barely useful. We'd really like anyone interested to resurrect the work and
908 finish it for a future release.</li>
909<li>If you're used to reading .ll files, you'll probably notice that .ll file
910 dumps don't produce #uses comments anymore. To get them, run a .bc file
911 through "llvm-dis --show-annotations".</li>
Chris Lattnerfcc65a72010-10-04 02:42:39 +0000[diff] [blame]912<li>Target triples are now stored in a normalized form, and all inputs from
913 humans are expected to be normalized by Triple::normalize before being
914 stored in a module triple or passed to another library.</li>
Chris Lattner87e04952010-04-21 05:17:40 +0000[diff] [blame]915</ul>
Chris Lattner934e2d42008-10-13 22:06:31 +0000[diff] [blame]916
Chris Lattnera7f45cf2010-10-04 01:29:06 +0000[diff] [blame]917
918
Chris Lattner934e2d42008-10-13 22:06:31 +0000[diff] [blame]919<p>In addition, many APIs have changed in this release. Some of the major LLVM
920API changes are:</p>
Chris Lattner934e2d42008-10-13 22:06:31 +0000[diff] [blame]921<ul>
Chris Lattner743bc472010-10-02 22:44:15 +0000[diff] [blame]922<li>LLVM 2.8 changes the internal order of operands in <a
923 href="http://llvm.org/doxygen/classllvm_1_1InvokeInst.html"><tt>InvokeInst</tt></a>
924 and <a href="http://llvm.org/doxygen/classllvm_1_1CallInst.html"><tt>CallInst</tt></a>.
Chris Lattnera7f45cf2010-10-04 01:29:06 +0000[diff] [blame]925 To be portable across releases, please use the <tt>CallSite</tt> class and the
926 high-level accessors, such as <tt>getCalledValue</tt> and
927 <tt>setUnwindDest</tt>.
Chris Lattner743bc472010-10-02 22:44:15 +0000[diff] [blame]928</li>
929<li>
Chris Lattnera7f45cf2010-10-04 01:29:06 +0000[diff] [blame]930 You can no longer pass use_iterators directly to cast&lt;&gt; (and similar),
931 because these routines tend to perform costly dereference operations more
932 than once. You have to dereference the iterators yourself and pass them in.
Chris Lattner743bc472010-10-02 22:44:15 +0000[diff] [blame]933</li>
934<li>
Chris Lattnera7f45cf2010-10-04 01:29:06 +0000[diff] [blame]935 llvm.memcpy.*, llvm.memset.*, llvm.memmove.* intrinsics take an extra
936 parameter now ("i1 isVolatile"), totaling 5 parameters, and the pointer
937 operands are now address-space qualified.
Chris Lattner743bc472010-10-02 22:44:15 +0000[diff] [blame]938 If you were creating these intrinsic calls and prototypes yourself (as opposed
Chris Lattnera7f45cf2010-10-04 01:29:06 +0000[diff] [blame]939 to using Intrinsic::getDeclaration), you can use
940 UpgradeIntrinsicFunction/UpgradeIntrinsicCall to be portable accross releases.
Chris Lattner743bc472010-10-02 22:44:15 +0000[diff] [blame]941</li>
942<li>
943 SetCurrentDebugLocation takes a DebugLoc now instead of a MDNode.
944 Change your code to use
945 SetCurrentDebugLocation(DebugLoc::getFromDILocation(...)).
946</li>
947<li>
Chris Lattner743bc472010-10-02 22:44:15 +0000[diff] [blame]948 The <tt>RegisterPass</tt> and <tt>RegisterAnalysisGroup</tt> templates are
949 considered deprecated, but continue to function in LLVM 2.8. Clients are
950 strongly advised to use the upcoming <tt>INITIALIZE_PASS()</tt> and
951 <tt>INITIALIZE_AG_PASS()</tt> macros instead.
Chris Lattner743bc472010-10-02 22:44:15 +0000[diff] [blame]952</li>
953<li>
954 The constructor for the Triple class no longer tries to understand odd triple
955 specifications. Frontends should ensure that they only pass valid triples to
956 LLVM. The Triple::normalize utility method has been added to help front-ends
957 deal with funky triples.
Chris Lattnera7f45cf2010-10-04 01:29:06 +0000[diff] [blame]958</li>
959
Chris Lattner743bc472010-10-02 22:44:15 +0000[diff] [blame]960<li>
961 Some APIs got renamed:
962 <ul>
Chris Lattnera7f45cf2010-10-04 01:29:06 +0000[diff] [blame]963 <li>llvm_report_error -&gt; report_fatal_error</li>
964 <li>llvm_install_error_handler -&gt; install_fatal_error_handler</li>
965 <li>llvm::DwarfExceptionHandling -&gt; llvm::JITExceptionHandling</li>
966 <li>VISIBILITY_HIDDEN -&gt; LLVM_LIBRARY_VISIBILITY</li>
Chris Lattner743bc472010-10-02 22:44:15 +0000[diff] [blame]967 </ul>
968</li>
969
Devang Pateldbf83832008-10-14 20:03:43 +0000[diff] [blame]970</ul>
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]971
Chris Lattner1e4d5bc2008-10-13 17:57:36 +0000[diff] [blame]972</div>
973
974
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]975<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]976<div class="doc_section">
977 <a name="knownproblems">Known Problems</a>
978</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]979<!-- *********************************************************************** -->
980
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]981<div class="doc_text">
982
Mikhail Glushenkov25422542009-03-01 18:09:47 +0000[diff] [blame]983<p>This section contains significant known problems with the LLVM system,
Chris Lattner2a092392008-11-10 05:40:34 +0000[diff] [blame]984listed by component. If you run into a problem, please check the <a
Chris Lattnera69595e2005-10-29 07:07:09 +0000[diff] [blame]985href="http://llvm.org/bugs/">LLVM bug database</a> and submit a bug if
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]986there isn't already one.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]987
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]988</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]989
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]990<!-- ======================================================================= -->
991<div class="doc_subsection">
992 <a name="experimental">Experimental features included with this release</a>
993</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]994
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]995<div class="doc_text">
996
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]997<p>The following components of this LLVM release are either untested, known to
998be broken or unreliable, or are in early development. These components should
999not be relied on, and bugs should not be filed against them, but they may be
1000useful 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]1001components, please contact us on the <a
1002href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev list</a>.</p>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]1003
1004<ul>
Chris Lattnera7f45cf2010-10-04 01:29:06 +0000[diff] [blame]1005<li>The Alpha, Blackfin, CellSPU, MicroBlaze, MSP430, MIPS, PIC16, SystemZ
1006 and XCore backends are experimental.</li>
Chris Lattnerbf1cf672010-10-02 21:59:30 +0000[diff] [blame]1007<li><tt>llc</tt> "<tt>-filetype=obj</tt>" is experimental on all targets
1008 other than darwin-i386 and darwin-x86_64.</li>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]1009</ul>
1010
1011</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]1012
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]1013<!-- ======================================================================= -->
1014<div class="doc_subsection">
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]1015 <a name="x86-be">Known problems with the X86 back-end</a>
John Criswell3bdbd302005-11-08 21:11:33 +0000[diff] [blame]1016</div>
1017
1018<div class="doc_text">
1019
1020<ul>
Anton Korobeynikov486c7d32008-06-08 10:24:13 +0000[diff] [blame]1021 <li>The X86 backend does not yet support
1022 all <a href="http://llvm.org/PR879">inline assembly that uses the X86
1023 floating point stack</a>. It supports the 'f' and 't' constraints, but not
1024 'u'.</li>
Duncan Sands0bc15262008-06-08 19:38:43 +0000[diff] [blame]1025 <li>Win64 code generation wasn't widely tested. Everything should work, but we
John Criswellea03c9d2009-03-02 15:28:15 +0000[diff] [blame]1026 expect small issues to happen. Also, llvm-gcc cannot build the mingw64
Chris Lattnera67df2d2010-04-22 06:28:20 +0000[diff] [blame]1027 runtime currently due to lack of support for the 'u' inline assembly
1028 constraint and for X87 floating point inline assembly.</li>
Dan Gohman721b3722008-06-08 23:05:11 +0000[diff] [blame]1029 <li>The X86-64 backend does not yet support the LLVM IR instruction
Chris Lattnera67df2d2010-04-22 06:28:20 +0000[diff] [blame]1030 <tt>va_arg</tt>. Currently, front-ends support variadic
Dan Gohman721b3722008-06-08 23:05:11 +0000[diff] [blame]1031 argument constructs on X86-64 by lowering them manually.</li>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]1032</ul>
1033
1034</div>
1035
1036<!-- ======================================================================= -->
1037<div class="doc_subsection">
1038 <a name="ppc-be">Known problems with the PowerPC back-end</a>
1039</div>
1040
1041<div class="doc_text">
1042
1043<ul>
Nicolas Geoffray77d99502007-05-15 09:21:28 +0000[diff] [blame]1044<li>The Linux PPC32/ABI support needs testing for the interpreter and static
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]1045compilation, and lacks support for debug information.</li>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]1046</ul>
1047
1048</div>
1049
1050<!-- ======================================================================= -->
1051<div class="doc_subsection">
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]1052 <a name="arm-be">Known problems with the ARM back-end</a>
1053</div>
1054
1055<div class="doc_text">
1056
1057<ul>
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]1058<li>Thumb mode works only on ARMv6 or higher processors. On sub-ARMv6
Duncan Sands47fc0a22007-09-26 15:59:54 +0000[diff] [blame]1059processors, thumb programs can crash or produce wrong
Chris Lattnerbee7b322007-05-23 04:39:32 +0000[diff] [blame]1060results (<a href="http://llvm.org/PR1388">PR1388</a>).</li>
John Criswellea03c9d2009-03-02 15:28:15 +0000[diff] [blame]1061<li>Compilation for ARM Linux OABI (old ABI) is supported but not fully tested.
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]1062</li>
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]1063</ul>
1064
1065</div>
1066
1067<!-- ======================================================================= -->
1068<div class="doc_subsection">
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]1069 <a name="sparc-be">Known problems with the SPARC back-end</a>
1070</div>
1071
1072<div class="doc_text">
1073
1074<ul>
John Criswellea03c9d2009-03-02 15:28:15 +0000[diff] [blame]1075<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]1076 support the 64-bit SPARC ABI (-m64).</li>
1077</ul>
1078
1079</div>
1080
1081<!-- ======================================================================= -->
1082<div class="doc_subsection">
Bruno Cardoso Lopes24eb3de2008-10-25 14:56:26 +0000[diff] [blame]1083 <a name="mips-be">Known problems with the MIPS back-end</a>
1084</div>
1085
1086<div class="doc_text">
1087
1088<ul>
Bruno Cardoso Lopes24eb3de2008-10-25 14:56:26 +0000[diff] [blame]1089<li>64-bit MIPS targets are not supported yet.</li>
1090</ul>
1091
1092</div>
1093
1094<!-- ======================================================================= -->
1095<div class="doc_subsection">
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]1096 <a name="alpha-be">Known problems with the Alpha back-end</a>
1097</div>
1098
1099<div class="doc_text">
1100
1101<ul>
1102
1103<li>On 21164s, some rare FP arithmetic sequences which may trap do not have the
1104appropriate nops inserted to ensure restartability.</li>
1105
John Criswell3bdbd302005-11-08 21:11:33 +0000[diff] [blame]1106</ul>
1107</div>
1108
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]1109<!-- ======================================================================= -->
1110<div class="doc_subsection">
Chris Lattner97beb512007-05-14 06:56:09 +0000[diff] [blame]1111 <a name="c-be">Known problems with the C back-end</a>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]1112</div>
1113
1114<div class="doc_text">
1115
Chris Lattner086d2692010-09-29 05:34:42 +0000[diff] [blame]1116<p>The C backend has numerous problems and is not being actively maintained.
1117Depending on it for anything serious is not advised.</p>
1118
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]1119<ul>
Chris Lattnera1a4c9a2008-06-05 06:35:40 +0000[diff] [blame]1120<li><a href="http://llvm.org/PR802">The C backend has only basic support for
1121 inline assembly code</a>.</li>
Chris Lattner8e061162007-09-26 06:01:35 +0000[diff] [blame]1122<li><a href="http://llvm.org/PR1658">The C backend violates the ABI of common
1123 C++ programs</a>, preventing intermixing between C++ compiled by the CBE and
Gabor Greif75b2f762009-03-02 12:02:51 +0000[diff] [blame]1124 C++ code compiled with <tt>llc</tt> or native compilers.</li>
Duncan Sandse09506a2008-02-10 13:40:55 +0000[diff] [blame]1125<li>The C backend does not support all exception handling constructs.</li>
Duncan Sands3aa36732009-02-25 11:51:54 +0000[diff] [blame]1126<li>The C backend does not support arbitrary precision integers.</li>
Chris Lattnerb81f10e2006-11-18 07:51:14 +0000[diff] [blame]1127</ul>
1128
1129</div>
John Criswell3bdbd302005-11-08 21:11:33 +0000[diff] [blame]1130
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]1131
1132<!-- ======================================================================= -->
1133<div class="doc_subsection">
Chris Lattner086d2692010-09-29 05:34:42 +0000[diff] [blame]1134 <a name="llvm-gcc">Known problems with the llvm-gcc front-end</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]1135</div>
Chris Lattner178f3db2003-10-02 05:07:23 +0000[diff] [blame]1136
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]1137<div class="doc_text">
Chris Lattner72a269f2006-03-03 00:34:26 +0000[diff] [blame]1138
Chris Lattner086d2692010-09-29 05:34:42 +0000[diff] [blame]1139<p>llvm-gcc is generally very stable for the C family of languages. The only
1140 major language feature of GCC not supported by llvm-gcc is the
1141 <tt>__builtin_apply</tt> family of builtins. However, some extensions
1142 are only supported on some targets. For example, trampolines are only
1143 supported on some targets (these are used when you take the address of a
1144 nested function).</p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]1145
Chris Lattner086d2692010-09-29 05:34:42 +0000[diff] [blame]1146<p>Fortran support generally works, but there are still several unresolved bugs
1147 in <a href="http://llvm.org/bugs/">Bugzilla</a>. Please see the
1148 tools/gfortran component for details. Note that llvm-gcc is missing major
1149 Fortran performance work in the frontend and library that went into GCC after
1150 4.2. If you are interested in Fortran, we recommend that you consider using
1151 <a href="#dragonegg">dragonegg</a> instead.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]1152
Chris Lattner086d2692010-09-29 05:34:42 +0000[diff] [blame]1153<p>The llvm-gcc 4.2 Ada compiler has basic functionality. However, this is not a
1154mature technology, and problems should be expected. For example:</p>
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]1155<ul>
Duncan Sands56448462008-06-08 20:18:35 +0000[diff] [blame]1156<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]1157to lack of trampoline support (pointers to nested functions) on other platforms.
1158However, 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]1159which does support trampolines.</li>
1160<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]1161This is due to lack of LLVM support for <tt>setjmp</tt>/<tt>longjmp</tt> style
1162exception handling, which is used internally by the compiler.
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]1163Workaround: configure with <tt>--disable-bootstrap</tt>.</li>
Duncan Sandsaef747f2008-10-13 17:27:23 +0000[diff] [blame]1164<li>The c380004, <a href="http://llvm.org/PR2010">c393010</a>
1165and <a href="http://llvm.org/PR2421">cxg2021</a> ACATS tests fail
Duncan Sandsd34bf762009-02-25 11:59:06 +0000[diff] [blame]1166(c380004 also fails with gcc-4.2 mainline).
1167If the compiler is built with checks disabled then <a href="http://llvm.org/PR2010">c393010</a>
1168causes the compiler to go into an infinite loop, using up all system memory.</li>
Duncan Sands2dbb00e2009-03-02 16:35:57 +0000[diff] [blame]1169<li>Some GCC specific Ada tests continue to crash the compiler.</li>
Chris Lattneraa61f412009-10-13 17:48:04 +0000[diff] [blame]1170<li>The <tt>-E</tt> binder option (exception backtraces)
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]1171<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]1172crashing if an exception is raised. Workaround: do not use <tt>-E</tt>.</li>
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]1173<li>Only discrete types <a href="http://llvm.org/PR1981">are allowed to start
1174or finish at a non-byte offset</a> in a record. Workaround: do not pack records
1175or use representation clauses that result in a field of a non-discrete type
1176starting or finishing in the middle of a byte.</li>
Chris Lattnerb076b002008-06-08 21:19:07 +0000[diff] [blame]1177<li>The <tt>lli</tt> interpreter <a href="http://llvm.org/PR2009">considers
1178'main' as generated by the Ada binder to be invalid</a>.
1179Workaround: hand edit the file to use pointers for <tt>argv</tt> and
1180<tt>envp</tt> rather than integers.</li>
1181<li>The <tt>-fstack-check</tt> option <a href="http://llvm.org/PR2008">is
1182ignored</a>.</li>
Chris Lattnere38ac152008-02-12 06:29:45 +0000[diff] [blame]1183</ul>
1184</div>
1185
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]1186<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]1187<div class="doc_section">
1188 <a name="additionalinfo">Additional Information</a>
1189</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]1190<!-- *********************************************************************** -->
1191
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]1192<div class="doc_text">
1193
Chris Lattnercb5596d2005-05-16 17:13:10 +0000[diff] [blame]1194<p>A wide variety of additional information is available on the <a
Chris Lattnere0c1df42007-05-18 00:44:29 +0000[diff] [blame]1195href="http://llvm.org">LLVM web page</a>, in particular in the <a
1196href="http://llvm.org/docs/">documentation</a> section. The web page also
Reid Spencerc7f87f22007-07-09 08:04:31 +0000[diff] [blame]1197contains versions of the API documentation which is up-to-date with the
1198Subversion version of the source code.
Misha Brukman96158092005-03-30 19:14:24 +0000[diff] [blame]1199You can access versions of these documents specific to this release by going
1200into the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]1201
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]1202<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]1203us via the <a href="http://llvm.org/docs/#maillist"> mailing
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]1204lists</a>.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]1205
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]1206</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]1207
1208<!-- *********************************************************************** -->
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]1209
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]1210<hr>
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]1211<address>
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Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]1216
Chris Lattnere0c1df42007-05-18 00:44:29 +0000[diff] [blame]1217 <a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]1218 Last modified: $Date$
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]1219</address>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]1220
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