Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +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> |
Reid Spencer | 6454ed3 | 2004-11-18 18:38:58 +0000 | [diff] [blame] | 5 | <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> |
Chris Lattner | 2fb6e5c | 2010-10-03 23:09:03 +0000 | [diff] [blame] | 6 | <meta encoding="utf8"> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 7 | <link rel="stylesheet" href="llvm.css" type="text/css"> |
Chris Lattner | be2e1b5 | 2011-03-10 07:43:44 +0000 | [diff] [blame] | 8 | <title>LLVM 2.9 Release Notes</title> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 9 | </head> |
| 10 | <body> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 11 | |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 12 | <h1 class="doc_title">LLVM 2.9 Release Notes</h1> |
Mikhail Glushenkov | ea65d7d | 2008-10-13 02:08:34 +0000 | [diff] [blame] | 13 | |
Chris Lattner | 0e464a9 | 2010-03-17 04:02:39 +0000 | [diff] [blame] | 14 | <img align=right src="http://llvm.org/img/DragonSmall.png" |
Gabor Greif | ee2187a | 2010-04-22 10:21:43 +0000 | [diff] [blame] | 15 | width="136" height="136" alt="LLVM Dragon Logo"> |
Chris Lattner | 0e464a9 | 2010-03-17 04:02:39 +0000 | [diff] [blame] | 16 | |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 17 | <ol> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 18 | <li><a href="#intro">Introduction</a></li> |
Chris Lattner | 96a445e | 2008-10-13 18:01:01 +0000 | [diff] [blame] | 19 | <li><a href="#subproj">Sub-project Status Update</a></li> |
Chris Lattner | be2e1b5 | 2011-03-10 07:43:44 +0000 | [diff] [blame] | 20 | <li><a href="#externalproj">External Projects Using LLVM 2.9</a></li> |
| 21 | <li><a href="#whatsnew">What's New in LLVM 2.9?</a></li> |
Chris Lattner | 4b538b9 | 2004-04-30 22:17:12 +0000 | [diff] [blame] | 22 | <li><a href="GettingStarted.html">Installation Instructions</a></li> |
Dan Gohman | 44aa921 | 2008-10-14 16:23:02 +0000 | [diff] [blame] | 23 | <li><a href="#knownproblems">Known Problems</a></li> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 24 | <li><a href="#additionalinfo">Additional Information</a></li> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 25 | </ol> |
| 26 | |
Chris Lattner | 7911ce2 | 2004-05-23 21:07:27 +0000 | [diff] [blame] | 27 | <div class="doc_author"> |
Dan Gohman | 44aa921 | 2008-10-14 16:23:02 +0000 | [diff] [blame] | 28 | <p>Written by the <a href="http://llvm.org">LLVM Team</a></p> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 29 | </div> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 30 | |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 31 | <!-- |
Chris Lattner | be2e1b5 | 2011-03-10 07:43:44 +0000 | [diff] [blame] | 32 | <h1 style="color:red">These are in-progress notes for the upcoming LLVM 2.9 |
Jeffrey Yasskin | bec4877 | 2010-01-28 01:14:43 +0000 | [diff] [blame] | 33 | release.<br> |
| 34 | You may prefer the |
Chris Lattner | be2e1b5 | 2011-03-10 07:43:44 +0000 | [diff] [blame] | 35 | <a href="http://llvm.org/releases/2.8/docs/ReleaseNotes.html">LLVM 2.8 |
Dan Gohman | b44f6c6 | 2010-05-03 23:51:05 +0000 | [diff] [blame] | 36 | Release Notes</a>.</h1> |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 37 | --> |
Jeffrey Yasskin | bec4877 | 2010-01-28 01:14:43 +0000 | [diff] [blame] | 38 | |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 39 | <!-- *********************************************************************** --> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 40 | <h1> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 41 | <a name="intro">Introduction</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 42 | </h1> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 43 | <!-- *********************************************************************** --> |
| 44 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 45 | <div class="doc_text"> |
| 46 | |
Chris Lattner | f6662f9 | 2008-10-13 17:57:36 +0000 | [diff] [blame] | 47 | <p>This document contains the release notes for the LLVM Compiler |
Chris Lattner | be2e1b5 | 2011-03-10 07:43:44 +0000 | [diff] [blame] | 48 | Infrastructure, release 2.9. Here we describe the status of LLVM, including |
Chris Lattner | f6662f9 | 2008-10-13 17:57:36 +0000 | [diff] [blame] | 49 | major improvements from the previous release and significant known problems. |
Mikhail Glushenkov | f795ef0 | 2009-03-01 18:09:47 +0000 | [diff] [blame] | 50 | All LLVM releases may be downloaded from the <a |
Chris Lattner | f6662f9 | 2008-10-13 17:57:36 +0000 | [diff] [blame] | 51 | href="http://llvm.org/releases/">LLVM releases web site</a>.</p> |
Chris Lattner | 1909261 | 2003-10-02 16:38:05 +0000 | [diff] [blame] | 52 | |
Chris Lattner | 7506b1d | 2004-12-07 08:04:13 +0000 | [diff] [blame] | 53 | <p>For more information about LLVM, including information about the latest |
Chris Lattner | c463b27 | 2005-10-29 07:07:09 +0000 | [diff] [blame] | 54 | release, please check out the <a href="http://llvm.org/">main LLVM |
Chris Lattner | 47ad72c | 2003-10-07 21:38:31 +0000 | [diff] [blame] | 55 | web site</a>. If you have questions or comments, the <a |
Chris Lattner | c66bfef | 2010-03-17 04:41:49 +0000 | [diff] [blame] | 56 | href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM Developer's |
| 57 | Mailing List</a> is a good place to send them.</p> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 58 | |
Mikhail Glushenkov | ea65d7d | 2008-10-13 02:08:34 +0000 | [diff] [blame] | 59 | <p>Note that if you are reading this file from a Subversion checkout or the |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame] | 60 | main LLVM web page, this document applies to the <i>next</i> release, not the |
Gabor Greif | fa933f8 | 2008-10-14 11:00:32 +0000 | [diff] [blame] | 61 | current one. To see the release notes for a specific release, please see the |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame] | 62 | <a href="http://llvm.org/releases/">releases page</a>.</p> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 63 | |
| 64 | </div> |
Chris Lattner | 61358ab | 2009-10-13 17:48:04 +0000 | [diff] [blame] | 65 | |
Chris Lattner | e4dc196 | 2011-04-05 23:22:33 +0000 | [diff] [blame] | 66 | <!-- Features that need text if they're finished for 3.1: |
| 67 | ARM EHABI |
Chris Lattner | 914ce46 | 2010-04-22 06:28:20 +0000 | [diff] [blame] | 68 | combiner-aa? |
Chris Lattner | 61358ab | 2009-10-13 17:48:04 +0000 | [diff] [blame] | 69 | strong phi elim |
Chris Lattner | 61358ab | 2009-10-13 17:48:04 +0000 | [diff] [blame] | 70 | loop dependence analysis |
Chris Lattner | e07043c | 2010-09-29 05:30:03 +0000 | [diff] [blame] | 71 | CorrelatedValuePropagation |
Chris Lattner | e4dc196 | 2011-04-05 23:22:33 +0000 | [diff] [blame] | 72 | lib/Transforms/IPO/MergeFunctions.cpp => consider for 3.1. |
Chris Lattner | acce85d | 2008-02-10 07:46:44 +0000 | [diff] [blame] | 73 | --> |
Chris Lattner | e07043c | 2010-09-29 05:30:03 +0000 | [diff] [blame] | 74 | |
Chris Lattner | 96a445e | 2008-10-13 18:01:01 +0000 | [diff] [blame] | 75 | <!-- *********************************************************************** --> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 76 | <h1> |
Chris Lattner | 96a445e | 2008-10-13 18:01:01 +0000 | [diff] [blame] | 77 | <a name="subproj">Sub-project Status Update</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 78 | </h1> |
Chris Lattner | 96a445e | 2008-10-13 18:01:01 +0000 | [diff] [blame] | 79 | <!-- *********************************************************************** --> |
Chris Lattner | ea34f64 | 2008-06-08 21:34:41 +0000 | [diff] [blame] | 80 | |
| 81 | <div class="doc_text"> |
Chris Lattner | 8348b47 | 2008-06-08 21:58:17 +0000 | [diff] [blame] | 82 | <p> |
Chris Lattner | be2e1b5 | 2011-03-10 07:43:44 +0000 | [diff] [blame] | 83 | The LLVM 2.9 distribution currently consists of code from the core LLVM |
Chris Lattner | 61358ab | 2009-10-13 17:48:04 +0000 | [diff] [blame] | 84 | repository (which roughly includes the LLVM optimizers, code generators |
| 85 | and supporting tools), the Clang repository and the llvm-gcc repository. In |
| 86 | addition to this code, the LLVM Project includes other sub-projects that are in |
| 87 | development. Here we include updates on these subprojects. |
Bill Wendling | 63d8c55 | 2009-03-02 04:28:57 +0000 | [diff] [blame] | 88 | </p> |
Chris Lattner | 96a445e | 2008-10-13 18:01:01 +0000 | [diff] [blame] | 89 | |
Chris Lattner | 8348b47 | 2008-06-08 21:58:17 +0000 | [diff] [blame] | 90 | </div> |
| 91 | |
Chris Lattner | 96a445e | 2008-10-13 18:01:01 +0000 | [diff] [blame] | 92 | |
Chris Lattner | 8348b47 | 2008-06-08 21:58:17 +0000 | [diff] [blame] | 93 | <!--=========================================================================--> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 94 | <h2> |
Chris Lattner | fb97b2d | 2008-10-13 18:11:54 +0000 | [diff] [blame] | 95 | <a name="clang">Clang: C/C++/Objective-C Frontend Toolkit</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 96 | </h2> |
Chris Lattner | 8348b47 | 2008-06-08 21:58:17 +0000 | [diff] [blame] | 97 | |
| 98 | <div class="doc_text"> |
| 99 | |
Chris Lattner | 095539f | 2010-04-26 17:42:18 +0000 | [diff] [blame] | 100 | <p><a href="http://clang.llvm.org/">Clang</a> is an LLVM front end for the C, |
| 101 | C++, and Objective-C languages. Clang aims to provide a better user experience |
| 102 | through expressive diagnostics, a high level of conformance to language |
| 103 | standards, fast compilation, and low memory use. Like LLVM, Clang provides a |
| 104 | modular, library-based architecture that makes it suitable for creating or |
| 105 | integrating with other development tools. Clang is considered a |
Chris Lattner | e07043c | 2010-09-29 05:30:03 +0000 | [diff] [blame] | 106 | production-quality compiler for C, Objective-C, C++ and Objective-C++ on x86 |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 107 | (32- and 64-bit), and for darwin/arm targets.</p> |
Chris Lattner | 61358ab | 2009-10-13 17:48:04 +0000 | [diff] [blame] | 108 | |
Chris Lattner | 0a6f6d5 | 2011-04-05 07:19:28 +0000 | [diff] [blame] | 109 | <p>In the LLVM 2.9 time-frame, the Clang team has made many improvements in C, |
| 110 | C++ and Objective-C support. C++ support is now generally rock solid, has |
Chris Lattner | df448a3 | 2011-04-06 00:56:12 +0000 | [diff] [blame] | 111 | been exercised on a broad variety of code, and has several new <a |
| 112 | href="http://clang.llvm.org/cxx_status.html#cxx0x">C++'0x features</a> |
Chris Lattner | 0a6f6d5 | 2011-04-05 07:19:28 +0000 | [diff] [blame] | 113 | implemented (such as rvalue references and variadic templates). LLVM 2.9 has |
| 114 | also brought in a large range of bug fixes and minor features (e.g. __label__ |
| 115 | support), and is much more compatible with the Linux Kernel.</p> |
| 116 | |
Duncan Sands | f3ba7af | 2011-04-06 08:07:40 +0000 | [diff] [blame] | 117 | <p>If Clang rejects your code but another compiler accepts it, please take a |
Chris Lattner | 0a6f6d5 | 2011-04-05 07:19:28 +0000 | [diff] [blame] | 118 | look at the <a href="http://clang.llvm.org/compatibility.html">language |
Duncan Sands | f3ba7af | 2011-04-06 08:07:40 +0000 | [diff] [blame] | 119 | compatibility</a> guide to make sure this is not intentional or a known issue. |
Chris Lattner | 0a6f6d5 | 2011-04-05 07:19:28 +0000 | [diff] [blame] | 120 | </p> |
Bill Wendling | 741748a | 2008-10-27 09:27:33 +0000 | [diff] [blame] | 121 | |
Chris Lattner | be2e1b5 | 2011-03-10 07:43:44 +0000 | [diff] [blame] | 122 | <ul> |
| 123 | </ul> |
Chris Lattner | fb97b2d | 2008-10-13 18:11:54 +0000 | [diff] [blame] | 124 | </div> |
| 125 | |
| 126 | <!--=========================================================================--> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 127 | <h2> |
Duncan Sands | 528a510 | 2011-04-04 11:09:08 +0000 | [diff] [blame] | 128 | <a name="dragonegg">DragonEgg: GCC front-ends, LLVM back-end</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 129 | </h2> |
Chris Lattner | 61358ab | 2009-10-13 17:48:04 +0000 | [diff] [blame] | 130 | |
| 131 | <div class="doc_text"> |
| 132 | <p> |
Duncan Sands | 528a510 | 2011-04-04 11:09:08 +0000 | [diff] [blame] | 133 | <a href="http://dragonegg.llvm.org/">DragonEgg</a> is a |
| 134 | <a href="http://gcc.gnu.org/wiki/plugins">gcc plugin</a> that replaces GCC's |
| 135 | optimizers and code generators with LLVM's. |
| 136 | Currently it requires a patched version of gcc-4.5. |
| 137 | The plugin can target the x86-32 and x86-64 processor families and has been |
| 138 | used successfully on the Darwin, FreeBSD and Linux platforms. |
| 139 | The Ada, C, C++ and Fortran languages work well. |
| 140 | The plugin is capable of compiling plenty of Obj-C, Obj-C++ and Java but it is |
| 141 | not known whether the compiled code actually works or not! |
Duncan Sands | 749fd83 | 2010-04-02 09:23:15 +0000 | [diff] [blame] | 142 | </p> |
| 143 | |
| 144 | <p> |
Chris Lattner | be2e1b5 | 2011-03-10 07:43:44 +0000 | [diff] [blame] | 145 | The 2.9 release has the following notable changes: |
Duncan Sands | 4b1da2b | 2010-09-30 17:37:34 +0000 | [diff] [blame] | 146 | <ul> |
Duncan Sands | 528a510 | 2011-04-04 11:09:08 +0000 | [diff] [blame] | 147 | <li>The plugin is much more stable when compiling Fortran.</li> |
Chris Lattner | df448a3 | 2011-04-06 00:56:12 +0000 | [diff] [blame] | 148 | <li>Inline assembly where an asm output is tied to an input of a different size |
| 149 | is now supported in many more cases.</li> |
Duncan Sands | 528a510 | 2011-04-04 11:09:08 +0000 | [diff] [blame] | 150 | <li>Basic support for the __float128 type was added. It is now possible to |
| 151 | generate LLVM IR from programs using __float128 but code generation does not |
| 152 | work yet.</li> |
| 153 | <li>Compiling Java programs no longer systematically crashes the plugin.</li> |
Duncan Sands | 4b1da2b | 2010-09-30 17:37:34 +0000 | [diff] [blame] | 154 | </ul> |
Chris Lattner | 61358ab | 2009-10-13 17:48:04 +0000 | [diff] [blame] | 155 | |
| 156 | </div> |
| 157 | |
Chris Lattner | 7554771 | 2010-10-03 23:49:06 +0000 | [diff] [blame] | 158 | <!--=========================================================================--> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 159 | <h2> |
Chris Lattner | 7554771 | 2010-10-03 23:49:06 +0000 | [diff] [blame] | 160 | <a name="compiler-rt">compiler-rt: Compiler Runtime Library</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 161 | </h2> |
Chris Lattner | 7554771 | 2010-10-03 23:49:06 +0000 | [diff] [blame] | 162 | |
| 163 | <div class="doc_text"> |
| 164 | <p> |
| 165 | The new LLVM <a href="http://compiler-rt.llvm.org/">compiler-rt project</a> |
| 166 | is a simple library that provides an implementation of the low-level |
| 167 | target-specific hooks required by code generation and other runtime components. |
| 168 | For example, when compiling for a 32-bit target, converting a double to a 64-bit |
| 169 | unsigned integer is compiled into a runtime call to the "__fixunsdfdi" |
| 170 | function. The compiler-rt library provides highly optimized implementations of |
| 171 | this and other low-level routines (some are 3x faster than the equivalent |
| 172 | libgcc routines).</p> |
| 173 | |
Chris Lattner | df448a3 | 2011-04-06 00:56:12 +0000 | [diff] [blame] | 174 | <p>In the LLVM 2.9 timeframe, compiler_rt has had several minor changes for |
| 175 | better ARM support, and a fairly major license change. All of the code in the |
| 176 | compiler-rt project is now <a href="DeveloperPolicy.html#license">dual |
| 177 | licensed</a> under MIT and UIUC license, which allows you to use compiler-rt |
| 178 | in applications without the binary copyright reproduction clause. If you |
| 179 | prefer the LLVM/UIUC license, you are free to continue using it under that |
| 180 | license as well.</p> |
Chris Lattner | 7554771 | 2010-10-03 23:49:06 +0000 | [diff] [blame] | 181 | |
| 182 | </div> |
Chris Lattner | 61358ab | 2009-10-13 17:48:04 +0000 | [diff] [blame] | 183 | |
| 184 | <!--=========================================================================--> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 185 | <h2> |
Chris Lattner | e07043c | 2010-09-29 05:30:03 +0000 | [diff] [blame] | 186 | <a name="lldb">LLDB: Low Level Debugger</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 187 | </h2> |
Chris Lattner | e07043c | 2010-09-29 05:30:03 +0000 | [diff] [blame] | 188 | |
| 189 | <div class="doc_text"> |
| 190 | <p> |
Chris Lattner | 7554771 | 2010-10-03 23:49:06 +0000 | [diff] [blame] | 191 | <a href="http://lldb.llvm.org/">LLDB</a> is a brand new member of the LLVM |
| 192 | umbrella of projects. LLDB is a next generation, high-performance debugger. It |
| 193 | is built as a set of reusable components which highly leverage existing |
| 194 | libraries in the larger LLVM Project, such as the Clang expression parser, the |
| 195 | LLVM disassembler and the LLVM JIT.</p> |
Chris Lattner | e07043c | 2010-09-29 05:30:03 +0000 | [diff] [blame] | 196 | |
| 197 | <p> |
Chris Lattner | df448a3 | 2011-04-06 00:56:12 +0000 | [diff] [blame] | 198 | LLDB is has advanced by leaps and bounds in the 2.9 timeframe. It is |
| 199 | dramatically more stable and useful, and includes both a new <a |
| 200 | href="http://lldb.llvm.org/tutorial.html">tutorial</a> and a <a |
| 201 | href="http://lldb.llvm.org/lldb-gdb.html">side-by-side comparison with |
| 202 | GDB</a>.</p> |
Chris Lattner | e07043c | 2010-09-29 05:30:03 +0000 | [diff] [blame] | 203 | |
| 204 | </div> |
| 205 | |
| 206 | <!--=========================================================================--> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 207 | <h2> |
Chris Lattner | e07043c | 2010-09-29 05:30:03 +0000 | [diff] [blame] | 208 | <a name="libc++">libc++: C++ Standard Library</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 209 | </h2> |
Chris Lattner | e07043c | 2010-09-29 05:30:03 +0000 | [diff] [blame] | 210 | |
| 211 | <div class="doc_text"> |
| 212 | <p> |
Tobias Grosser | cdce44b | 2010-10-06 21:07:30 +0000 | [diff] [blame] | 213 | <a href="http://libcxx.llvm.org/">libc++</a> is another new member of the LLVM |
Chris Lattner | 7554771 | 2010-10-03 23:49:06 +0000 | [diff] [blame] | 214 | family. It is an implementation of the C++ standard library, written from the |
| 215 | ground up to specifically target the forthcoming C++'0X standard and focus on |
| 216 | delivering great performance.</p> |
Chris Lattner | e07043c | 2010-09-29 05:30:03 +0000 | [diff] [blame] | 217 | |
| 218 | <p> |
Chris Lattner | 2009c49 | 2011-04-06 00:59:18 +0000 | [diff] [blame] | 219 | In the LLVM 2.9 timeframe, libc++ has had numerous bugs fixed, and is now being |
| 220 | co-developed with Clang's C++'0x mode.</p> |
Chris Lattner | 0a6f6d5 | 2011-04-05 07:19:28 +0000 | [diff] [blame] | 221 | |
Chris Lattner | 2009c49 | 2011-04-06 00:59:18 +0000 | [diff] [blame] | 222 | <p> |
| 223 | Like compiler_rt, libc++ is now <a href="DeveloperPolicy.html#license">dual |
| 224 | licensed</a> under the MIT and UIUC license, allowing it to be used more |
| 225 | permissively. |
Chris Lattner | e07043c | 2010-09-29 05:30:03 +0000 | [diff] [blame] | 226 | </p> |
| 227 | |
| 228 | </div> |
| 229 | |
Chris Lattner | 61358ab | 2009-10-13 17:48:04 +0000 | [diff] [blame] | 230 | |
Daniel Dunbar | 97b01a8 | 2010-10-04 17:39:47 +0000 | [diff] [blame] | 231 | |
| 232 | <!--=========================================================================--> |
Chris Lattner | 7a8e6c5 | 2011-04-05 18:38:45 +0000 | [diff] [blame] | 233 | <!-- |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 234 | <h2> |
Daniel Dunbar | 97b01a8 | 2010-10-04 17:39:47 +0000 | [diff] [blame] | 235 | <a name="klee">KLEE: A Symbolic Execution Virtual Machine</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 236 | </h2> |
Daniel Dunbar | 97b01a8 | 2010-10-04 17:39:47 +0000 | [diff] [blame] | 237 | |
| 238 | <div class="doc_text"> |
| 239 | <p> |
| 240 | <a href="http://klee.llvm.org/">KLEE</a> is a symbolic execution framework for |
| 241 | programs in LLVM bitcode form. KLEE tries to symbolically evaluate "all" paths |
| 242 | through the application and records state transitions that lead to fault |
| 243 | states. This allows it to construct testcases that lead to faults and can even |
| 244 | be used to verify some algorithms. |
| 245 | </p> |
| 246 | |
Chris Lattner | be2e1b5 | 2011-03-10 07:43:44 +0000 | [diff] [blame] | 247 | <p>UPDATE!</p> |
Chris Lattner | 7a8e6c5 | 2011-04-05 18:38:45 +0000 | [diff] [blame] | 248 | </div>--> |
Daniel Dunbar | 97b01a8 | 2010-10-04 17:39:47 +0000 | [diff] [blame] | 249 | |
| 250 | |
Chris Lattner | ab68e9e | 2009-02-26 22:33:38 +0000 | [diff] [blame] | 251 | <!-- *********************************************************************** --> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 252 | <h1> |
Chris Lattner | be2e1b5 | 2011-03-10 07:43:44 +0000 | [diff] [blame] | 253 | <a name="externalproj">External Open Source Projects Using LLVM 2.9</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 254 | </h1> |
Chris Lattner | ab68e9e | 2009-02-26 22:33:38 +0000 | [diff] [blame] | 255 | <!-- *********************************************************************** --> |
| 256 | |
Chris Lattner | 61358ab | 2009-10-13 17:48:04 +0000 | [diff] [blame] | 257 | <div class="doc_text"> |
| 258 | |
| 259 | <p>An exciting aspect of LLVM is that it is used as an enabling technology for |
| 260 | a lot of other language and tools projects. This section lists some of the |
Chris Lattner | be2e1b5 | 2011-03-10 07:43:44 +0000 | [diff] [blame] | 261 | projects that have already been updated to work with LLVM 2.9.</p> |
Chris Lattner | 7c8e796 | 2010-04-26 17:38:10 +0000 | [diff] [blame] | 262 | </div> |
| 263 | |
Chris Lattner | 7554771 | 2010-10-03 23:49:06 +0000 | [diff] [blame] | 264 | |
Chris Lattner | 3bfe57e | 2011-04-06 01:13:49 +0000 | [diff] [blame] | 265 | <!--=========================================================================--> |
| 266 | <h2>Crack Programming Language</h2> |
| 267 | |
| 268 | <div class="doc_text"> |
| 269 | <p> |
| 270 | <a href="http://code.google.com/p/crack-language/">Crack</a> aims to provide the |
| 271 | ease of development of a scripting language with the performance of a compiled |
| 272 | language. The language derives concepts from C++, Java and Python, incorporating |
| 273 | object-oriented programming, operator overloading and strong typing.</p> |
| 274 | </div> |
| 275 | |
| 276 | |
| 277 | <!--=========================================================================--> |
| 278 | <h2>TTA-based Codesign Environment (TCE)</h2> |
| 279 | |
| 280 | <div class="doc_text"> |
| 281 | <p>TCE is a toolset for designing application-specific processors (ASP) based on |
| 282 | the Transport triggered architecture (TTA). The toolset provides a complete |
| 283 | co-design flow from C/C++ programs down to synthesizable VHDL and parallel |
| 284 | program binaries. Processor customization points include the register files, |
| 285 | function units, supported operations, and the interconnection network.</p> |
| 286 | |
| 287 | <p>TCE uses Clang and LLVM for C/C++ language support, target independent |
| 288 | optimizations and also for parts of code generation. It generates new LLVM-based |
| 289 | code generators "on the fly" for the designed TTA processors and loads them in |
| 290 | to the compiler backend as runtime libraries to avoid per-target recompilation |
| 291 | of larger parts of the compiler chain.</p> |
| 292 | </div> |
| 293 | |
| 294 | |
| 295 | |
| 296 | <!--=========================================================================--> |
| 297 | <h2>PinaVM</h2> |
| 298 | |
| 299 | <div class="doc_text"> |
| 300 | <p><a href="http://gitorious.org/pinavm/pages/Home">PinaVM</a> is an open |
| 301 | source, <a href="http://www.systemc.org/">SystemC</a> front-end. Unlike many |
| 302 | other front-ends, PinaVM actually executes the elaboration of the |
| 303 | program analyzed using LLVM's JIT infrastructure. It later enriches the |
| 304 | bitcode with SystemC-specific information.</p> |
| 305 | </div> |
| 306 | |
| 307 | <!--=========================================================================--> |
| 308 | <h2>Pure</h2> |
| 309 | |
| 310 | <div class="doc_text"> |
| 311 | <p><a href="http://pure-lang.googlecode.com/">Pure</a> is an |
| 312 | algebraic/functional |
| 313 | programming language based on term rewriting. Programs are collections |
| 314 | of equations which are used to evaluate expressions in a symbolic |
| 315 | fashion. The interpreter uses LLVM as a backend to JIT-compile Pure |
| 316 | programs to fast native code. Pure offers dynamic typing, eager and lazy |
| 317 | evaluation, lexical closures, a hygienic macro system (also based on |
| 318 | term rewriting), built-in list and matrix support (including list and |
| 319 | matrix comprehensions) and an easy-to-use interface to C and other |
| 320 | programming languages (including the ability to load LLVM bitcode |
| 321 | modules, and inline C, C++, Fortran and Faust code in Pure programs if |
| 322 | the corresponding LLVM-enabled compilers are installed).</p> |
| 323 | |
| 324 | <p>Pure version 0.47 has been tested and is known to work with LLVM 2.9 |
| 325 | (and continues to work with older LLVM releases >= 2.5).</p> |
| 326 | </div> |
| 327 | |
| 328 | <!--=========================================================================--> |
| 329 | <h2 id="icedtea">IcedTea Java Virtual Machine Implementation</h2> |
| 330 | |
| 331 | <div class="doc_text"> |
| 332 | <p> |
| 333 | <a href="http://icedtea.classpath.org/wiki/Main_Page">IcedTea</a> provides a |
| 334 | harness to build OpenJDK using only free software build tools and to provide |
| 335 | replacements for the not-yet free parts of OpenJDK. One of the extensions that |
| 336 | IcedTea provides is a new JIT compiler named <a |
| 337 | href="http://icedtea.classpath.org/wiki/ZeroSharkFaq">Shark</a> which uses LLVM |
| 338 | to provide native code generation without introducing processor-dependent |
| 339 | code. |
| 340 | </p> |
| 341 | |
| 342 | <p> OpenJDK 7 b112, IcedTea6 1.9 and IcedTea7 1.13 and later have been tested |
| 343 | and are known to work with LLVM 2.9 (and continue to work with older LLVM |
| 344 | releases >= 2.6 as well).</p> |
| 345 | </div> |
| 346 | |
| 347 | <!--=========================================================================--> |
| 348 | <h2>Glasgow Haskell Compiler (GHC)</h2> |
| 349 | |
| 350 | <div class="doc_text"> |
| 351 | <p>GHC is an open source, state-of-the-art programming suite for Haskell, |
| 352 | a standard lazy functional programming language. It includes an |
| 353 | optimizing static compiler generating good code for a variety of |
| 354 | platforms, together with an interactive system for convenient, quick |
| 355 | development.</p> |
| 356 | |
| 357 | <p>In addition to the existing C and native code generators, GHC 7.0 now |
| 358 | supports an LLVM code generator. GHC supports LLVM 2.7 and later.</p> |
| 359 | </div> |
| 360 | |
| 361 | <!--=========================================================================--> |
| 362 | <h2>Polly - Polyhedral optimizations for LLVM</h2> |
| 363 | |
| 364 | <div class="doc_text"> |
| 365 | <p>Polly is a project that aims to provide advanced memory access optimizations |
| 366 | to better take advantage of SIMD units, cache hierarchies, multiple cores or |
| 367 | even vector accelerators for LLVM. Built around an abstract mathematical |
| 368 | description based on Z-polyhedra, it provides the infrastructure to develop |
| 369 | advanced optimizations in LLVM and to connect complex external optimizers. In |
| 370 | its first year of existence Polly already provides an exact value-based |
| 371 | dependency analysis as well as basic SIMD and OpenMP code generation support. |
| 372 | Furthermore, Polly can use PoCC(Pluto) an advanced optimizer for data-locality |
| 373 | and parallelism.</p> |
| 374 | </div> |
Chris Lattner | 7554771 | 2010-10-03 23:49:06 +0000 | [diff] [blame] | 375 | |
Chris Lattner | e051844 | 2010-10-01 06:34:49 +0000 | [diff] [blame] | 376 | |
Chris Lattner | 8348b47 | 2008-06-08 21:58:17 +0000 | [diff] [blame] | 377 | <!-- *********************************************************************** --> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 378 | <h1> |
Chris Lattner | be2e1b5 | 2011-03-10 07:43:44 +0000 | [diff] [blame] | 379 | <a name="whatsnew">What's New in LLVM 2.9?</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 380 | </h1> |
Chris Lattner | 8348b47 | 2008-06-08 21:58:17 +0000 | [diff] [blame] | 381 | <!-- *********************************************************************** --> |
| 382 | |
Chris Lattner | f8e0b4e | 2008-06-08 22:59:35 +0000 | [diff] [blame] | 383 | <div class="doc_text"> |
| 384 | |
Chris Lattner | 61358ab | 2009-10-13 17:48:04 +0000 | [diff] [blame] | 385 | <p>This release includes a huge number of bug fixes, performance tweaks and |
Chris Lattner | f6662f9 | 2008-10-13 17:57:36 +0000 | [diff] [blame] | 386 | minor improvements. Some of the major improvements and new features are listed |
| 387 | in this section. |
Chris Lattner | f8e0b4e | 2008-06-08 22:59:35 +0000 | [diff] [blame] | 388 | </p> |
Chris Lattner | 61358ab | 2009-10-13 17:48:04 +0000 | [diff] [blame] | 389 | |
Chris Lattner | 914ce46 | 2010-04-22 06:28:20 +0000 | [diff] [blame] | 390 | </div> |
| 391 | |
| 392 | <!--=========================================================================--> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 393 | <h2> |
Chris Lattner | 252b83d | 2008-02-06 18:00:06 +0000 | [diff] [blame] | 394 | <a name="majorfeatures">Major New Features</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 395 | </h2> |
Chris Lattner | 252b83d | 2008-02-06 18:00:06 +0000 | [diff] [blame] | 396 | |
| 397 | <div class="doc_text"> |
| 398 | |
Chris Lattner | be2e1b5 | 2011-03-10 07:43:44 +0000 | [diff] [blame] | 399 | <p>LLVM 2.9 includes several major new capabilities:</p> |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 400 | |
| 401 | <ul> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 402 | |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 403 | <li>Type Based Alias Analysis (TBAA) is now implemented and turned on by default |
| 404 | in Clang. This allows substantially better load/store optimization in some |
| 405 | cases. TBAA can be disabled by passing -fno-strict-aliasing. |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 406 | </li> |
| 407 | |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 408 | <li>This release has seen a continued focus on quality of debug information. |
| 409 | LLVM now generates much higher fidelity debug information, particularly when |
| 410 | debugging optimized code.</li> |
| 411 | |
| 412 | <li>Inline assembly now supports multiple alternative constraints.</li> |
| 413 | |
| 414 | <li>A new backend for the NVIDIA PTX virtual ISA (used to target its GPUs) is |
| 415 | under rapid development. It is not generally useful in 2.9, but is making |
| 416 | rapid progress.</li> |
Chris Lattner | 7a8e6c5 | 2011-04-05 18:38:45 +0000 | [diff] [blame] | 417 | |
Chris Lattner | 8170c10 | 2008-02-10 08:18:42 +0000 | [diff] [blame] | 418 | </ul> |
Chris Lattner | 0a6f6d5 | 2011-04-05 07:19:28 +0000 | [diff] [blame] | 419 | |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 420 | </div> |
| 421 | |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame] | 422 | <!--=========================================================================--> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 423 | <h2> |
Chris Lattner | 917cc71 | 2009-03-02 02:37:32 +0000 | [diff] [blame] | 424 | <a name="coreimprovements">LLVM IR and Core Improvements</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 425 | </h2> |
Chris Lattner | f304ffc | 2008-02-10 08:17:19 +0000 | [diff] [blame] | 426 | |
| 427 | <div class="doc_text"> |
Chris Lattner | 61358ab | 2009-10-13 17:48:04 +0000 | [diff] [blame] | 428 | <p>LLVM IR has several new features for better support of new targets and that |
| 429 | expose new optimization opportunities:</p> |
Chris Lattner | f304ffc | 2008-02-10 08:17:19 +0000 | [diff] [blame] | 430 | |
Chris Lattner | 791f77b | 2008-06-05 06:25:56 +0000 | [diff] [blame] | 431 | <ul> |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 432 | <li>The <a href="LangRef.html#bitwiseops">udiv, ashr, lshr, and shl</a> |
| 433 | instructions now have support exact and nuw/nsw bits to indicate that they |
| 434 | don't overflow or shift out bits. This is useful for optimization of <a |
| 435 | href="http://llvm.org/PR8862">pointer differences</a> and other cases.</li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 436 | |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 437 | <li>LLVM IR now supports the <a href="LangRef.html#globalvars">unnamed_addr</a> |
| 438 | attribute to indicate that constant global variables with identical |
| 439 | initializers can be merged. This fixed <a href="http://llvm.org/PR8927">an |
| 440 | issue</a> where LLVM would incorrectly merge two globals which were supposed |
| 441 | to have distinct addresses.</li> |
| 442 | |
| 443 | <li>The new <a href="LangRef.html#fnattrs">hotpatch attribute</a> has been added |
| 444 | to allow runtime patching of functions.</li> |
Chris Lattner | f304ffc | 2008-02-10 08:17:19 +0000 | [diff] [blame] | 445 | </ul> |
Mikhail Glushenkov | ea65d7d | 2008-10-13 02:08:34 +0000 | [diff] [blame] | 446 | |
Chris Lattner | f304ffc | 2008-02-10 08:17:19 +0000 | [diff] [blame] | 447 | </div> |
| 448 | |
| 449 | <!--=========================================================================--> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 450 | <h2> |
Chris Lattner | acce85d | 2008-02-10 07:46:44 +0000 | [diff] [blame] | 451 | <a name="optimizer">Optimizer Improvements</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 452 | </h2> |
Chris Lattner | acce85d | 2008-02-10 07:46:44 +0000 | [diff] [blame] | 453 | |
| 454 | <div class="doc_text"> |
| 455 | |
Chris Lattner | 61358ab | 2009-10-13 17:48:04 +0000 | [diff] [blame] | 456 | <p>In addition to a large array of minor performance tweaks and bug fixes, this |
Chris Lattner | f301387 | 2008-10-13 21:50:36 +0000 | [diff] [blame] | 457 | release includes a few major enhancements and additions to the optimizers:</p> |
Chris Lattner | acce85d | 2008-02-10 07:46:44 +0000 | [diff] [blame] | 458 | |
| 459 | <ul> |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 460 | <li>Link Time Optimization (LTO) has been improved to use MC for parsing inline |
| 461 | assembly and now can build large programs like Firefox 4 on both Mac OS X and |
| 462 | Linux.</li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 463 | |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 464 | <li>The new -loop-idiom pass recognizes memset/memcpy loops (and memset_pattern |
| 465 | on darwin), turning them into library calls, which are typically better |
| 466 | optimized than inline code. If you are building a libc and notice that your |
| 467 | memcpy and memset functions are compiled into infinite recursion, please build |
| 468 | with -ffreestanding or -fno-builtin to disable this pass.</li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 469 | |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 470 | <li>A new -early-cse pass does a fast pass over functions to fold constants, |
| 471 | simplify expressions, perform simple dead store elimination, and perform |
| 472 | common subexpression elimination. It does a good job at catching some of the |
| 473 | trivial redundancies that exist in unoptimized code, making later passes more |
| 474 | effective.<,/li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 475 | |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 476 | <li>A new -loop-instsimplify pass is used to clean up loop bodies in the loop |
| 477 | optimizer.</li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 478 | |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 479 | <li>The new TargetLibraryInfo interface allows mid-level optimizations to know |
| 480 | whether the current target's runtime library has certain functions. For |
| 481 | example, the optimizer can now transform integer-only printf calls to call |
| 482 | iprintf, allowing reduced code size for embedded C libraries (e.g. newlib). |
| 483 | </li> |
| 484 | |
| 485 | <li>LLVM has a new <a href="WritingAnLLVMPass.html#RegionPass">RegionPass</a> |
| 486 | infrastructure for region-based optimizations.</li> |
| 487 | |
| 488 | <li>Several optimizer passes have been substantially sped up: |
| 489 | GVN is much faster on functions with deep dominator trees and lots of basic |
| 490 | blocks. The dominator tree and dominance frontier passes are much faster to |
| 491 | compute, and preserved by more passes (so they are computed less often). The |
| 492 | -scalar-repl pass is also much faster and doesn't use DominanceFrontier. |
| 493 | </li> |
| 494 | |
| 495 | <li>The Dead Store Elimination pass is more aggressive optimizing stores of |
| 496 | different types: e.g. a large store following a small one to the same address. |
| 497 | The MemCpyOptimizer pass handles several new forms of memcpy elimination.</li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 498 | |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 499 | <li>LLVM now optimizes various idioms for overflow detection into check of the |
| 500 | flag register on various CPUs. For example, we now compile: |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 501 | |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 502 | <pre> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 503 | unsigned long t = a+b; |
| 504 | if (t < a) ... |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 505 | </pre> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 506 | into: |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 507 | <pre> |
| 508 | addq %rdi, %rbx |
| 509 | jno LBB0_2 |
| 510 | </pre> |
| 511 | </li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 512 | |
Chris Lattner | 11b6611 | 2010-10-04 02:42:39 +0000 | [diff] [blame] | 513 | </ul> |
| 514 | |
Chris Lattner | 61358ab | 2009-10-13 17:48:04 +0000 | [diff] [blame] | 515 | </div> |
Chris Lattner | 917cc71 | 2009-03-02 02:37:32 +0000 | [diff] [blame] | 516 | |
Chris Lattner | 0b83220 | 2008-06-08 02:45:07 +0000 | [diff] [blame] | 517 | <!--=========================================================================--> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 518 | <h2> |
Chris Lattner | 4ba2b65 | 2010-09-30 16:31:33 +0000 | [diff] [blame] | 519 | <a name="mc">MC Level Improvements</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 520 | </h2> |
Chris Lattner | 4ba2b65 | 2010-09-30 16:31:33 +0000 | [diff] [blame] | 521 | |
| 522 | <div class="doc_text"> |
| 523 | <p> |
Chris Lattner | 7d9b6b4 | 2010-10-02 21:59:30 +0000 | [diff] [blame] | 524 | The LLVM Machine Code (aka MC) subsystem was created to solve a number |
Chris Lattner | 4ba2b65 | 2010-09-30 16:31:33 +0000 | [diff] [blame] | 525 | of problems in the realm of assembly, disassembly, object file format handling, |
| 526 | and a number of other related areas that CPU instruction-set level tools work |
Chris Lattner | 7d9b6b4 | 2010-10-02 21:59:30 +0000 | [diff] [blame] | 527 | in.</p> |
| 528 | |
Chris Lattner | 7d9b6b4 | 2010-10-02 21:59:30 +0000 | [diff] [blame] | 529 | <ul> |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 530 | <li>ELF MC support has matured enough for the integrated assembler to be turned |
| 531 | on by default in Clang on X86-32 and X86-64 ELF systems.</li> |
| 532 | |
| 533 | <li>MC supports and CodeGen uses the <tt>.file</tt> and <tt>.loc</tt> directives |
| 534 | for producing line number debug info. This produces more compact line |
| 535 | tables and easier to read .s files.</li> |
| 536 | |
| 537 | <li>MC supports the <tt>.cfi_*</tt> directives for producing DWARF |
Rafael Espindola | a26f36c | 2011-03-18 04:07:44 +0000 | [diff] [blame] | 538 | frame information, but it is still not used by CodeGen by default.</li> |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 539 | |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 540 | |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 541 | <li>The MC assembler now generates much better diagnostics for common errors, |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 542 | is much faster at matching instructions, is much more bug-compatible with |
| 543 | the GAS assembler, and is now generally useful for a broad range of X86 |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 544 | assembly.</li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 545 | |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 546 | <li>We now have some basic <a href="CodeGenerator.html#mc">internals |
| 547 | documentation</a> for MC.</li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 548 | |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 549 | <li>.td files can now specify assembler aliases directly with the <a |
| 550 | href="CodeGenerator.html#na_instparsing">MnemonicAlias and InstAlias</a> |
| 551 | tblgen classes.</li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 552 | |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 553 | <li>LLVM now has an experimental format-independent object file manipulation |
| 554 | library (lib/Object). It supports both PE/COFF and ELF. The llvm-nm tool has |
| 555 | been extended to work with native object files, and the new llvm-objdump tool |
| 556 | supports disassembly of object files (but no relocations are displayed yet). |
| 557 | </li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 558 | |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 559 | <li>Win32 PE-COFF support in the MC assembler has made a lot of progress in the |
| 560 | 2.9 timeframe, but is still not generally useful.</li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 561 | |
Chris Lattner | 7d9b6b4 | 2010-10-02 21:59:30 +0000 | [diff] [blame] | 562 | </ul> |
| 563 | |
| 564 | <p>For more information, please see the <a |
Chris Lattner | 4ba2b65 | 2010-09-30 16:31:33 +0000 | [diff] [blame] | 565 | href="http://blog.llvm.org/2010/04/intro-to-llvm-mc-project.html">Intro to the |
| 566 | LLVM MC Project Blog Post</a>. |
| 567 | </p> |
| 568 | |
NAKAMURA Takumi | 45c435a | 2011-04-05 08:24:22 +0000 | [diff] [blame] | 569 | </div> |
Chris Lattner | 4ba2b65 | 2010-09-30 16:31:33 +0000 | [diff] [blame] | 570 | |
Chris Lattner | 4ba2b65 | 2010-09-30 16:31:33 +0000 | [diff] [blame] | 571 | <!--=========================================================================--> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 572 | <h2> |
Chris Lattner | 511433e | 2009-03-02 03:24:11 +0000 | [diff] [blame] | 573 | <a name="codegen">Target Independent Code Generator Improvements</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 574 | </h2> |
Chris Lattner | 0b83220 | 2008-06-08 02:45:07 +0000 | [diff] [blame] | 575 | |
| 576 | <div class="doc_text"> |
| 577 | |
Mikhail Glushenkov | f795ef0 | 2009-03-01 18:09:47 +0000 | [diff] [blame] | 578 | <p>We have put a significant amount of work into the code generator |
| 579 | infrastructure, which allows us to implement more aggressive algorithms and make |
| 580 | it run faster:</p> |
Chris Lattner | 0b83220 | 2008-06-08 02:45:07 +0000 | [diff] [blame] | 581 | |
| 582 | <ul> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 583 | <li>The pre-register-allocation (preRA) instruction scheduler models register |
| 584 | pressure much more accurately in some cases. This allows the adoption of more |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 585 | aggressive scheduling heuristics without causing spills to be generated. |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 586 | </li> |
| 587 | |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 588 | <li>LiveDebugVariables is a new pass that keeps track of debugging information |
| 589 | for user variables that are promoted to registers in optimized builds.</li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 590 | |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 591 | <li>The scheduler now models operand latency and pipeline forwarding.</li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 592 | |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 593 | <li>A major register allocator infrastructure rewrite is underway. It is not on |
| 594 | by default for 2.9 and you are not advised to use it, but it has made |
| 595 | substantial progress in the 2.9 timeframe: |
| 596 | <ul> |
| 597 | <li>A new -regalloc=basic "basic" register allocator can be used as a simple |
| 598 | fallback when debugging. It uses the new infrastructure.</li> |
| 599 | <li>New infrastructure is in place for live range splitting. "SplitKit" can |
| 600 | break a live interval into smaller pieces while preserving SSA form, and |
| 601 | SpillPlacement can help find the best split points. This is a work in |
| 602 | progress so the API is changing quickly.</li> |
| 603 | <li>The inline spiller has learned to clean up after live range splitting. It |
| 604 | can hoist spills out of loops, and it can eliminate redundant spills.</li> |
| 605 | <li>Rematerialization works with live range splitting.</li> |
| 606 | <li>The new "greedy" register allocator using live range splitting. This will |
| 607 | be the default register allocator in the next LLVM release, but it is not |
| 608 | turned on by default in 2.9.</li> |
| 609 | </ul> |
| 610 | </li> |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame] | 611 | </ul> |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame] | 612 | </div> |
| 613 | |
Chris Lattner | 917cc71 | 2009-03-02 02:37:32 +0000 | [diff] [blame] | 614 | <!--=========================================================================--> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 615 | <h2> |
Chris Lattner | 917cc71 | 2009-03-02 02:37:32 +0000 | [diff] [blame] | 616 | <a name="x86">X86-32 and X86-64 Target Improvements</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 617 | </h2> |
Chris Lattner | 917cc71 | 2009-03-02 02:37:32 +0000 | [diff] [blame] | 618 | |
| 619 | <div class="doc_text"> |
Chris Lattner | 7714c91 | 2010-10-04 04:39:25 +0000 | [diff] [blame] | 620 | <p>New features and major changes in the X86 target include: |
Chris Lattner | 917cc71 | 2009-03-02 02:37:32 +0000 | [diff] [blame] | 621 | </p> |
| 622 | |
| 623 | <ul> |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 624 | <li>LLVM 2.9 includes a complete reimplementation of the MMX instruction set. |
| 625 | The reimplementation uses a new LLVM IR <a |
| 626 | href="LangRef.html#t_x86mmx">x86_mmx</a> type to ensure that MMX operations |
| 627 | are <em>only</em> generated from source that uses MMX builtin operations. With |
Duncan Sands | f3ba7af | 2011-04-06 08:07:40 +0000 | [diff] [blame] | 628 | this, random types like <2 x i32> are not turned into MMX operations |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 629 | (which can be catastrophic without proper "emms" insertion). Because the X86 |
| 630 | code generator always generates reliable code, the -disable-mmx flag is now |
| 631 | removed. |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 632 | </li> |
| 633 | |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 634 | <li>X86 support for FS/GS relative loads and stores using <a |
Jay Foad | cb88ec3 | 2011-04-06 07:55:30 +0000 | [diff] [blame] | 635 | href="CodeGenerator.html#x86_memory">address space 256/257</a> works reliably |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 636 | now.</li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 637 | |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 638 | <li>LLVM 2.9 generates much better code in several cases by using adc/sbb to |
| 639 | avoid generation of conditional move instructions for conditional increment |
| 640 | and other idioms.</li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 641 | |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 642 | <li>The X86 backend has adopted a new preRA scheduling mode, "list-ilp", to |
| 643 | shorten the height of instruction schedules without inducing register spills. |
| 644 | </li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 645 | |
Jay Foad | cb88ec3 | 2011-04-06 07:55:30 +0000 | [diff] [blame] | 646 | <li>The MC assembler supports 3dNow! and 3DNowA instructions.</li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 647 | |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 648 | <li>Several bugs have been fixed for Windows x64 code generator.</li> |
Chris Lattner | 917cc71 | 2009-03-02 02:37:32 +0000 | [diff] [blame] | 649 | </ul> |
| 650 | |
Chris Lattner | 917cc71 | 2009-03-02 02:37:32 +0000 | [diff] [blame] | 651 | </div> |
Chris Lattner | 8497764 | 2007-09-21 03:54:09 +0000 | [diff] [blame] | 652 | |
| 653 | <!--=========================================================================--> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 654 | <h2> |
Chris Lattner | 61358ab | 2009-10-13 17:48:04 +0000 | [diff] [blame] | 655 | <a name="ARM">ARM Target Improvements</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 656 | </h2> |
Chris Lattner | c441fb8 | 2009-03-01 02:30:21 +0000 | [diff] [blame] | 657 | |
| 658 | <div class="doc_text"> |
Chris Lattner | 61358ab | 2009-10-13 17:48:04 +0000 | [diff] [blame] | 659 | <p>New features of the ARM target include: |
| 660 | </p> |
Chris Lattner | c441fb8 | 2009-03-01 02:30:21 +0000 | [diff] [blame] | 661 | |
| 662 | <ul> |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 663 | <li>The ARM backend now has a fast instruction selector, which dramatically |
| 664 | improves -O0 compile times.</li> |
| 665 | <li>The ARM backend has new tuning for Cortex-A8 and Cortex-A9 CPUs.</li> |
| 666 | <li>The __builtin_prefetch builtin (and llvm.prefetch intrinsic) is compiled |
| 667 | into prefetch instructions instead of being discarded.</li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 668 | |
| 669 | <li> The ARM backend preRA scheduler now models machine resources at cycle |
| 670 | granularity. This allows the scheduler to both accurately model |
| 671 | instruction latency and avoid overcommitting functional units.</li> |
| 672 | |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 673 | <li>Countless ARM microoptimizations have landed in LLVM 2.9.</li> |
Bob Wilson | e847277 | 2010-09-13 17:39:35 +0000 | [diff] [blame] | 674 | </ul> |
Chris Lattner | 61358ab | 2009-10-13 17:48:04 +0000 | [diff] [blame] | 675 | </div> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 676 | |
| 677 | <!--=========================================================================--> |
| 678 | <h2> |
| 679 | <a name="OtherTS">Other Target Specific Improvements</a> |
| 680 | </h2> |
Chris Lattner | c441fb8 | 2009-03-01 02:30:21 +0000 | [diff] [blame] | 681 | |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 682 | <div class="doc_text"> |
| 683 | <ul> |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 684 | <li>MicroBlaze: major updates for aggressive delay slot filler, MC-based |
| 685 | assembly printing, assembly instruction parsing, ELF .o file emission, and MC |
| 686 | instruction disassembler have landed.</li> |
| 687 | |
| 688 | <li>SPARC: Many improvements, including using the Y registers for |
| 689 | multiplications and addition of a simple delay slot filler.</li> |
| 690 | |
| 691 | <li>PowerPC: The backend has been largely MC'ized and is ready to support |
Duncan Sands | f3ba7af | 2011-04-06 08:07:40 +0000 | [diff] [blame] | 692 | directly writing out mach-o object files. No one seems interested in finishing |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 693 | this final step though.</li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 694 | |
| 695 | </ul> |
| 696 | </div> |
Chris Lattner | 77d29b1 | 2008-06-05 08:02:49 +0000 | [diff] [blame] | 697 | |
| 698 | <!--=========================================================================--> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 699 | <h2> |
Chris Lattner | f6662f9 | 2008-10-13 17:57:36 +0000 | [diff] [blame] | 700 | <a name="changes">Major Changes and Removed Features</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 701 | </h2> |
Chris Lattner | f6662f9 | 2008-10-13 17:57:36 +0000 | [diff] [blame] | 702 | |
| 703 | <div class="doc_text"> |
| 704 | |
Chris Lattner | eeb4da0 | 2008-10-13 22:06:31 +0000 | [diff] [blame] | 705 | <p>If you're already an LLVM user or developer with out-of-tree changes based |
Chris Lattner | be2e1b5 | 2011-03-10 07:43:44 +0000 | [diff] [blame] | 706 | on LLVM 2.8, this section lists some "gotchas" that you may run into upgrading |
Chris Lattner | eeb4da0 | 2008-10-13 22:06:31 +0000 | [diff] [blame] | 707 | from the previous release.</p> |
Chris Lattner | f6662f9 | 2008-10-13 17:57:36 +0000 | [diff] [blame] | 708 | |
| 709 | <ul> |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 710 | <li><b>This is the last release to support the llvm-gcc frontend.</b></li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 711 | |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 712 | <li>LLVM has a new <a href="CodingStandards.html#ll_naming">naming |
| 713 | convention standard</a>, though the codebase hasn't fully adopted it yet.</li> |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 714 | |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 715 | <li>The new DIBuilder class provides a simpler interface for front ends to |
| 716 | encode debug info in LLVM IR, and has replaced DIFactory.</li> |
Chris Lattner | c5ac61d | 2011-04-06 05:50:04 +0000 | [diff] [blame] | 717 | |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 718 | <li>LLVM IR and other tools always work on normalized target triples (which have |
| 719 | been run through <tt>Triple::normalize</tt>).</li> |
| 720 | |
| 721 | <li>The target triple x86_64--mingw64 is obsoleted. Use x86_64--mingw32 |
| 722 | instead.</li> |
| 723 | |
| 724 | <li>The PointerTracking pass has been removed from mainline, and moved to The |
| 725 | ClamAV project (its only client).</li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 726 | |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 727 | <li>The LoopIndexSplit, LiveValues, SimplifyHalfPowrLibCalls, GEPSplitter, and |
| 728 | PartialSpecialization passes were removed. They were unmaintained, |
Duncan Sands | f3ba7af | 2011-04-06 08:07:40 +0000 | [diff] [blame] | 729 | buggy, or deemed to be a bad idea.</li> |
Devang Patel | b34dd13 | 2008-10-14 20:03:43 +0000 | [diff] [blame] | 730 | </ul> |
Chris Lattner | f6662f9 | 2008-10-13 17:57:36 +0000 | [diff] [blame] | 731 | |
Chris Lattner | f6662f9 | 2008-10-13 17:57:36 +0000 | [diff] [blame] | 732 | </div> |
| 733 | |
Daniel Dunbar | f0233c6 | 2010-10-04 20:11:41 +0000 | [diff] [blame] | 734 | <!--=========================================================================--> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 735 | <h2> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 736 | <a name="api_changes">Internal API Changes</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 737 | </h2> |
Daniel Dunbar | f0233c6 | 2010-10-04 20:11:41 +0000 | [diff] [blame] | 738 | |
| 739 | <div class="doc_text"> |
| 740 | |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 741 | <p>In addition, many APIs have changed in this release. Some of the major |
| 742 | LLVM API changes are:</p> |
Daniel Dunbar | f0233c6 | 2010-10-04 20:11:41 +0000 | [diff] [blame] | 743 | |
| 744 | <ul> |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 745 | <li>include/llvm/System merged into include/llvm/Support.</li> |
| 746 | <li>The <a href="http://llvm.org/PR5207">llvm::APInt API</a> was significantly |
| 747 | cleaned up.</li> |
Chris Lattner | 1efe27e | 2011-04-06 00:45:11 +0000 | [diff] [blame] | 748 | |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 749 | <li>In the code generator, MVT::Flag was renamed to MVT::Glue to more accurately |
| 750 | describe its behavior.</li> |
| 751 | |
| 752 | <li>The system_error header from C++0x was added, and is now pervasively used to |
| 753 | capture and handle i/o and other errors in LLVM.</li> |
| 754 | |
| 755 | <li>The old sys::Path API has been deprecated in favor of the new PathV2 API, |
| 756 | which is more efficient and flexible.</li> |
Daniel Dunbar | f0233c6 | 2010-10-04 20:11:41 +0000 | [diff] [blame] | 757 | </ul> |
| 758 | </div> |
Chris Lattner | f6662f9 | 2008-10-13 17:57:36 +0000 | [diff] [blame] | 759 | |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 760 | <!-- *********************************************************************** --> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 761 | <h1> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 762 | <a name="knownproblems">Known Problems</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 763 | </h1> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 764 | <!-- *********************************************************************** --> |
| 765 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 766 | <div class="doc_text"> |
| 767 | |
Mikhail Glushenkov | f795ef0 | 2009-03-01 18:09:47 +0000 | [diff] [blame] | 768 | <p>This section contains significant known problems with the LLVM system, |
Chris Lattner | e18b32e | 2008-11-10 05:40:34 +0000 | [diff] [blame] | 769 | listed by component. If you run into a problem, please check the <a |
Chris Lattner | c463b27 | 2005-10-29 07:07:09 +0000 | [diff] [blame] | 770 | href="http://llvm.org/bugs/">LLVM bug database</a> and submit a bug if |
Chris Lattner | 5eccca4 | 2003-12-12 21:22:16 +0000 | [diff] [blame] | 771 | there isn't already one.</p> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 772 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 773 | </div> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 774 | |
Chris Lattner | f5ee170 | 2004-03-14 02:03:02 +0000 | [diff] [blame] | 775 | <!-- ======================================================================= --> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 776 | <h2> |
Chris Lattner | f5ee170 | 2004-03-14 02:03:02 +0000 | [diff] [blame] | 777 | <a name="experimental">Experimental features included with this release</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 778 | </h2> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 779 | |
Chris Lattner | f5ee170 | 2004-03-14 02:03:02 +0000 | [diff] [blame] | 780 | <div class="doc_text"> |
| 781 | |
Misha Brukman | 6df9e2c | 2004-05-12 21:46:05 +0000 | [diff] [blame] | 782 | <p>The following components of this LLVM release are either untested, known to |
| 783 | be broken or unreliable, or are in early development. These components should |
| 784 | not be relied on, and bugs should not be filed against them, but they may be |
| 785 | useful to some people. In particular, if you would like to work on one of these |
Chris Lattner | 2b659ef | 2008-02-12 06:29:45 +0000 | [diff] [blame] | 786 | components, please contact us on the <a |
| 787 | href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev list</a>.</p> |
Chris Lattner | f5ee170 | 2004-03-14 02:03:02 +0000 | [diff] [blame] | 788 | |
| 789 | <ul> |
Chris Lattner | be2e1b5 | 2011-03-10 07:43:44 +0000 | [diff] [blame] | 790 | <li>The Alpha, Blackfin, CellSPU, MicroBlaze, MSP430, MIPS, PTX, SystemZ |
Chris Lattner | bb11771 | 2010-10-04 01:29:06 +0000 | [diff] [blame] | 791 | and XCore backends are experimental.</li> |
Chris Lattner | 7d9b6b4 | 2010-10-02 21:59:30 +0000 | [diff] [blame] | 792 | <li><tt>llc</tt> "<tt>-filetype=obj</tt>" is experimental on all targets |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 793 | other than darwin and ELF X86 systems.</li> |
Chris Lattner | be2e1b5 | 2011-03-10 07:43:44 +0000 | [diff] [blame] | 794 | |
Chris Lattner | f5ee170 | 2004-03-14 02:03:02 +0000 | [diff] [blame] | 795 | </ul> |
| 796 | |
| 797 | </div> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 798 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 799 | <!-- ======================================================================= --> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 800 | <h2> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 801 | <a name="x86-be">Known problems with the X86 back-end</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 802 | </h2> |
John Criswell | c0c186d | 2005-11-08 21:11:33 +0000 | [diff] [blame] | 803 | |
| 804 | <div class="doc_text"> |
| 805 | |
| 806 | <ul> |
Anton Korobeynikov | a6094be | 2008-06-08 10:24:13 +0000 | [diff] [blame] | 807 | <li>The X86 backend does not yet support |
| 808 | all <a href="http://llvm.org/PR879">inline assembly that uses the X86 |
| 809 | floating point stack</a>. It supports the 'f' and 't' constraints, but not |
| 810 | 'u'.</li> |
Dan Gohman | 8207ba9 | 2008-06-08 23:05:11 +0000 | [diff] [blame] | 811 | <li>The X86-64 backend does not yet support the LLVM IR instruction |
Chris Lattner | 914ce46 | 2010-04-22 06:28:20 +0000 | [diff] [blame] | 812 | <tt>va_arg</tt>. Currently, front-ends support variadic |
Dan Gohman | 8207ba9 | 2008-06-08 23:05:11 +0000 | [diff] [blame] | 813 | argument constructs on X86-64 by lowering them manually.</li> |
NAKAMURA Takumi | 45c435a | 2011-04-05 08:24:22 +0000 | [diff] [blame] | 814 | <li>Windows x64 (aka Win64) code generator has a few issues. |
| 815 | <ul> |
| 816 | <li>llvm-gcc cannot build the mingw-w64 runtime currently |
| 817 | due to lack of support for the 'u' inline assembly |
| 818 | constraint and for X87 floating point inline assembly.</li> |
| 819 | <li>On mingw-w64, you will see unresolved symbol <tt>__chkstk</tt> |
| 820 | due to <a href="http://llvm.org/bugs/show_bug.cgi?id=8919">Bug 8919</a>. |
| 821 | It is fixed in <a href="http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20110321/118499.html">r128206</a>.</li> |
| 822 | <li>Miss-aligned MOVDQA might crash your program. It is due to |
| 823 | <a href="http://llvm.org/bugs/show_bug.cgi?id=9483">Bug 9483</a>, |
| 824 | lack of handling aligned internal globals.</li> |
| 825 | </ul> |
| 826 | </li> |
| 827 | |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 828 | </ul> |
| 829 | |
| 830 | </div> |
| 831 | |
| 832 | <!-- ======================================================================= --> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 833 | <h2> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 834 | <a name="ppc-be">Known problems with the PowerPC back-end</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 835 | </h2> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 836 | |
| 837 | <div class="doc_text"> |
| 838 | |
| 839 | <ul> |
Nicolas Geoffray | e4285dc | 2007-05-15 09:21:28 +0000 | [diff] [blame] | 840 | <li>The Linux PPC32/ABI support needs testing for the interpreter and static |
Chris Lattner | 57a460e | 2007-05-23 04:39:32 +0000 | [diff] [blame] | 841 | compilation, and lacks support for debug information.</li> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 842 | </ul> |
| 843 | |
| 844 | </div> |
| 845 | |
| 846 | <!-- ======================================================================= --> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 847 | <h2> |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 848 | <a name="arm-be">Known problems with the ARM back-end</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 849 | </h2> |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 850 | |
| 851 | <div class="doc_text"> |
| 852 | |
| 853 | <ul> |
Chris Lattner | 57a460e | 2007-05-23 04:39:32 +0000 | [diff] [blame] | 854 | <li>Thumb mode works only on ARMv6 or higher processors. On sub-ARMv6 |
Duncan Sands | c90d68b | 2007-09-26 15:59:54 +0000 | [diff] [blame] | 855 | processors, thumb programs can crash or produce wrong |
Chris Lattner | 57a460e | 2007-05-23 04:39:32 +0000 | [diff] [blame] | 856 | results (<a href="http://llvm.org/PR1388">PR1388</a>).</li> |
John Criswell | 524a5dd | 2009-03-02 15:28:15 +0000 | [diff] [blame] | 857 | <li>Compilation for ARM Linux OABI (old ABI) is supported but not fully tested. |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 858 | </li> |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 859 | </ul> |
| 860 | |
| 861 | </div> |
| 862 | |
| 863 | <!-- ======================================================================= --> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 864 | <h2> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 865 | <a name="sparc-be">Known problems with the SPARC back-end</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 866 | </h2> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 867 | |
| 868 | <div class="doc_text"> |
| 869 | |
| 870 | <ul> |
John Criswell | 524a5dd | 2009-03-02 15:28:15 +0000 | [diff] [blame] | 871 | <li>The SPARC backend only supports the 32-bit SPARC ABI (-m32); it does not |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 872 | support the 64-bit SPARC ABI (-m64).</li> |
| 873 | </ul> |
| 874 | |
| 875 | </div> |
| 876 | |
| 877 | <!-- ======================================================================= --> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 878 | <h2> |
Bruno Cardoso Lopes | b7e1a4f | 2008-10-25 14:56:26 +0000 | [diff] [blame] | 879 | <a name="mips-be">Known problems with the MIPS back-end</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 880 | </h2> |
Bruno Cardoso Lopes | b7e1a4f | 2008-10-25 14:56:26 +0000 | [diff] [blame] | 881 | |
| 882 | <div class="doc_text"> |
| 883 | |
| 884 | <ul> |
Bruno Cardoso Lopes | b7e1a4f | 2008-10-25 14:56:26 +0000 | [diff] [blame] | 885 | <li>64-bit MIPS targets are not supported yet.</li> |
| 886 | </ul> |
| 887 | |
| 888 | </div> |
| 889 | |
| 890 | <!-- ======================================================================= --> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 891 | <h2> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 892 | <a name="alpha-be">Known problems with the Alpha back-end</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 893 | </h2> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 894 | |
| 895 | <div class="doc_text"> |
| 896 | |
| 897 | <ul> |
| 898 | |
| 899 | <li>On 21164s, some rare FP arithmetic sequences which may trap do not have the |
| 900 | appropriate nops inserted to ensure restartability.</li> |
| 901 | |
John Criswell | c0c186d | 2005-11-08 21:11:33 +0000 | [diff] [blame] | 902 | </ul> |
| 903 | </div> |
| 904 | |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 905 | <!-- ======================================================================= --> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 906 | <h2> |
Chris Lattner | f3e5bc6 | 2007-05-14 06:56:09 +0000 | [diff] [blame] | 907 | <a name="c-be">Known problems with the C back-end</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 908 | </h2> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 909 | |
| 910 | <div class="doc_text"> |
| 911 | |
Chris Lattner | 3016ee9 | 2010-09-29 05:34:42 +0000 | [diff] [blame] | 912 | <p>The C backend has numerous problems and is not being actively maintained. |
| 913 | Depending on it for anything serious is not advised.</p> |
| 914 | |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 915 | <ul> |
Chris Lattner | 5733b27 | 2008-06-05 06:35:40 +0000 | [diff] [blame] | 916 | <li><a href="http://llvm.org/PR802">The C backend has only basic support for |
| 917 | inline assembly code</a>.</li> |
Chris Lattner | 725a0d8 | 2007-09-26 06:01:35 +0000 | [diff] [blame] | 918 | <li><a href="http://llvm.org/PR1658">The C backend violates the ABI of common |
| 919 | C++ programs</a>, preventing intermixing between C++ compiled by the CBE and |
Gabor Greif | 4906abe | 2009-03-02 12:02:51 +0000 | [diff] [blame] | 920 | C++ code compiled with <tt>llc</tt> or native compilers.</li> |
Duncan Sands | f74c0cc | 2008-02-10 13:40:55 +0000 | [diff] [blame] | 921 | <li>The C backend does not support all exception handling constructs.</li> |
Duncan Sands | 50723a9 | 2009-02-25 11:51:54 +0000 | [diff] [blame] | 922 | <li>The C backend does not support arbitrary precision integers.</li> |
Chris Lattner | 2629922 | 2006-11-18 07:51:14 +0000 | [diff] [blame] | 923 | </ul> |
| 924 | |
| 925 | </div> |
John Criswell | c0c186d | 2005-11-08 21:11:33 +0000 | [diff] [blame] | 926 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 927 | |
| 928 | <!-- ======================================================================= --> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 929 | <h2> |
Chris Lattner | 3016ee9 | 2010-09-29 05:34:42 +0000 | [diff] [blame] | 930 | <a name="llvm-gcc">Known problems with the llvm-gcc front-end</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 931 | </h2> |
Chris Lattner | 47588f9 | 2003-10-02 05:07:23 +0000 | [diff] [blame] | 932 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 933 | <div class="doc_text"> |
Chris Lattner | c5d658a | 2006-03-03 00:34:26 +0000 | [diff] [blame] | 934 | |
Chris Lattner | 49123fd | 2011-04-06 06:29:50 +0000 | [diff] [blame] | 935 | <p><b>LLVM 2.9 will be the last release of llvm-gcc.</b></p> |
| 936 | |
Chris Lattner | 3016ee9 | 2010-09-29 05:34:42 +0000 | [diff] [blame] | 937 | <p>llvm-gcc is generally very stable for the C family of languages. The only |
| 938 | major language feature of GCC not supported by llvm-gcc is the |
| 939 | <tt>__builtin_apply</tt> family of builtins. However, some extensions |
| 940 | are only supported on some targets. For example, trampolines are only |
| 941 | supported on some targets (these are used when you take the address of a |
| 942 | nested function).</p> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 943 | |
Chris Lattner | 3016ee9 | 2010-09-29 05:34:42 +0000 | [diff] [blame] | 944 | <p>Fortran support generally works, but there are still several unresolved bugs |
| 945 | in <a href="http://llvm.org/bugs/">Bugzilla</a>. Please see the |
| 946 | tools/gfortran component for details. Note that llvm-gcc is missing major |
| 947 | Fortran performance work in the frontend and library that went into GCC after |
| 948 | 4.2. If you are interested in Fortran, we recommend that you consider using |
| 949 | <a href="#dragonegg">dragonegg</a> instead.</p> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 950 | |
Duncan Sands | 3af9633 | 2010-10-04 10:06:56 +0000 | [diff] [blame] | 951 | <p>The llvm-gcc 4.2 Ada compiler has basic functionality, but is no longer being |
| 952 | actively maintained. If you are interested in Ada, we recommend that you |
| 953 | consider using <a href="#dragonegg">dragonegg</a> instead.</p> |
Chris Lattner | 2b659ef | 2008-02-12 06:29:45 +0000 | [diff] [blame] | 954 | </div> |
| 955 | |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 956 | <!-- *********************************************************************** --> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 957 | <h1> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 958 | <a name="additionalinfo">Additional Information</a> |
NAKAMURA Takumi | c631931 | 2011-04-05 21:55:14 +0000 | [diff] [blame] | 959 | </h1> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 960 | <!-- *********************************************************************** --> |
| 961 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 962 | <div class="doc_text"> |
| 963 | |
Chris Lattner | 416db10 | 2005-05-16 17:13:10 +0000 | [diff] [blame] | 964 | <p>A wide variety of additional information is available on the <a |
Chris Lattner | b4b0ce7 | 2007-05-18 00:44:29 +0000 | [diff] [blame] | 965 | href="http://llvm.org">LLVM web page</a>, in particular in the <a |
| 966 | href="http://llvm.org/docs/">documentation</a> section. The web page also |
Reid Spencer | 669ed45 | 2007-07-09 08:04:31 +0000 | [diff] [blame] | 967 | contains versions of the API documentation which is up-to-date with the |
| 968 | Subversion version of the source code. |
Misha Brukman | 109d9e8 | 2005-03-30 19:14:24 +0000 | [diff] [blame] | 969 | You can access versions of these documents specific to this release by going |
| 970 | into the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 971 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 972 | <p>If you have any questions or comments about LLVM, please feel free to contact |
Chris Lattner | c463b27 | 2005-10-29 07:07:09 +0000 | [diff] [blame] | 973 | us via the <a href="http://llvm.org/docs/#maillist"> mailing |
Chris Lattner | 5eccca4 | 2003-12-12 21:22:16 +0000 | [diff] [blame] | 974 | lists</a>.</p> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 975 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 976 | </div> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 977 | |
| 978 | <!-- *********************************************************************** --> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 979 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 980 | <hr> |
Misha Brukman | 2061e89 | 2003-11-22 01:23:39 +0000 | [diff] [blame] | 981 | <address> |
Misha Brukman | 38847d5 | 2003-12-21 22:53:21 +0000 | [diff] [blame] | 982 | <a href="http://jigsaw.w3.org/css-validator/check/referer"><img |
Misha Brukman | 4440870 | 2008-12-11 17:34:48 +0000 | [diff] [blame] | 983 | src="http://jigsaw.w3.org/css-validator/images/vcss-blue" alt="Valid CSS"></a> |
Misha Brukman | 2061e89 | 2003-11-22 01:23:39 +0000 | [diff] [blame] | 984 | <a href="http://validator.w3.org/check/referer"><img |
Misha Brukman | 4440870 | 2008-12-11 17:34:48 +0000 | [diff] [blame] | 985 | src="http://www.w3.org/Icons/valid-html401-blue" alt="Valid HTML 4.01"></a> |
Misha Brukman | 2061e89 | 2003-11-22 01:23:39 +0000 | [diff] [blame] | 986 | |
Chris Lattner | b4b0ce7 | 2007-05-18 00:44:29 +0000 | [diff] [blame] | 987 | <a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br> |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 988 | Last modified: $Date$ |
Misha Brukman | 2061e89 | 2003-11-22 01:23:39 +0000 | [diff] [blame] | 989 | </address> |
Chris Lattner | 79c3fe1 | 2003-10-02 04:57:28 +0000 | [diff] [blame] | 990 | |
Misha Brukman | 500bc30 | 2003-11-22 00:38:41 +0000 | [diff] [blame] | 991 | </body> |
| 992 | </html> |