forked from OSchip/llvm-project
814 lines
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814 lines
27 KiB
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
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"http://www.w3.org/TR/html4/strict.dtd">
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<html>
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<head>
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<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
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<link rel="stylesheet" href="llvm.css" type="text/css">
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<title>LLVM 2.8 Release Notes</title>
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</head>
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<body>
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<div class="doc_title">LLVM 2.8 Release Notes</div>
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<img align=right src="http://llvm.org/img/DragonSmall.png"
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width="136" height="136" alt="LLVM Dragon Logo">
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<ol>
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<li><a href="#intro">Introduction</a></li>
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<li><a href="#subproj">Sub-project Status Update</a></li>
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<li><a href="#externalproj">External Projects Using LLVM 2.8</a></li>
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<li><a href="#whatsnew">What's New in LLVM 2.8?</a></li>
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<li><a href="GettingStarted.html">Installation Instructions</a></li>
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<li><a href="#portability">Portability and Supported Platforms</a></li>
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<li><a href="#knownproblems">Known Problems</a></li>
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<li><a href="#additionalinfo">Additional Information</a></li>
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</ol>
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<div class="doc_author">
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<p>Written by the <a href="http://llvm.org">LLVM Team</a></p>
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</div>
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<h1 style="color:red">These are in-progress notes for the upcoming LLVM 2.8
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release.<br>
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You may prefer the
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<a href="http://llvm.org/releases/2.7/docs/ReleaseNotes.html">LLVM 2.7
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Release Notes</a>.</h1>
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<!-- *********************************************************************** -->
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<div class="doc_section">
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<a name="intro">Introduction</a>
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</div>
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<!-- *********************************************************************** -->
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<div class="doc_text">
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<p>This document contains the release notes for the LLVM Compiler
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Infrastructure, release 2.8. Here we describe the status of LLVM, including
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major improvements from the previous release and significant known problems.
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All LLVM releases may be downloaded from the <a
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href="http://llvm.org/releases/">LLVM releases web site</a>.</p>
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<p>For more information about LLVM, including information about the latest
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release, please check out the <a href="http://llvm.org/">main LLVM
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web site</a>. If you have questions or comments, the <a
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href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM Developer's
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Mailing List</a> is a good place to send them.</p>
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<p>Note that if you are reading this file from a Subversion checkout or the
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main LLVM web page, this document applies to the <i>next</i> release, not the
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current one. To see the release notes for a specific release, please see the
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<a href="http://llvm.org/releases/">releases page</a>.</p>
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</div>
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<!--
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Almost dead code.
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include/llvm/Analysis/LiveValues.h => Dan
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lib/Transforms/IPO/MergeFunctions.cpp => consider for 2.8.
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llvm/Analysis/PointerTracking.h => Edwin wants this, consider for 2.8.
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GEPSplitterPass
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-->
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<!-- Features that need text if they're finished for 2.8:
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combiner-aa?
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strong phi elim
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llvm.dbg.value: variable debug info for optimized code
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loop dependence analysis
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TBAA
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-->
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<!-- for announcement email:
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Logo web page.
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Many new papers added to /pubs/
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-->
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<!-- *********************************************************************** -->
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<div class="doc_section">
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<a name="subproj">Sub-project Status Update</a>
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</div>
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<!-- *********************************************************************** -->
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<div class="doc_text">
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<p>
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The LLVM 2.8 distribution currently consists of code from the core LLVM
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repository (which roughly includes the LLVM optimizers, code generators
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and supporting tools), the Clang repository and the llvm-gcc repository. In
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addition to this code, the LLVM Project includes other sub-projects that are in
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development. Here we include updates on these subprojects.
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</p>
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</div>
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<!--=========================================================================-->
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<div class="doc_subsection">
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<a name="clang">Clang: C/C++/Objective-C Frontend Toolkit</a>
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</div>
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<div class="doc_text">
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<p><a href="http://clang.llvm.org/">Clang</a> is an LLVM front end for the C,
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C++, and Objective-C languages. Clang aims to provide a better user experience
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through expressive diagnostics, a high level of conformance to language
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standards, fast compilation, and low memory use. Like LLVM, Clang provides a
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modular, library-based architecture that makes it suitable for creating or
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integrating with other development tools. Clang is considered a
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production-quality compiler for C and Objective-C on x86 (32- and 64-bit).</p>
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<p>In the LLVM 2.8 time-frame, the Clang team has made many improvements:</p>
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<ul>
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</ul>
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</div>
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<!--=========================================================================-->
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<div class="doc_subsection">
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<a name="clangsa">Clang Static Analyzer</a>
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</div>
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<div class="doc_text">
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<p>The <a href="http://clang-analyzer.llvm.org/">Clang Static Analyzer</a>
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project is an effort to use static source code analysis techniques to
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automatically find bugs in C and Objective-C programs (and hopefully <a
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href="http://clang-analyzer.llvm.org/dev_cxx.html">C++ in the
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future</a>!). The tool is very good at finding bugs that occur on specific
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paths through code, such as on error conditions.</p>
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<p>In the LLVM 2.8 time-frame,
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</p>
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</div>
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<!--=========================================================================-->
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<div class="doc_subsection">
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<a name="vmkit">VMKit: JVM/CLI Virtual Machine Implementation</a>
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</div>
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<div class="doc_text">
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<p>
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The <a href="http://vmkit.llvm.org/">VMKit project</a> is an implementation of
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a JVM and a CLI Virtual Machine (Microsoft .NET is an
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implementation of the CLI) using LLVM for static and just-in-time
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compilation.</p>
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<p>With the release of LLVM 2.8, ...</p>
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</div>
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<!--=========================================================================-->
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<div class="doc_subsection">
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<a name="compiler-rt">compiler-rt: Compiler Runtime Library</a>
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</div>
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<div class="doc_text">
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<p>
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The new LLVM <a href="http://compiler-rt.llvm.org/">compiler-rt project</a>
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is a simple library that provides an implementation of the low-level
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target-specific hooks required by code generation and other runtime components.
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For example, when compiling for a 32-bit target, converting a double to a 64-bit
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unsigned integer is compiled into a runtime call to the "__fixunsdfdi"
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function. The compiler-rt library provides highly optimized implementations of
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this and other low-level routines (some are 3x faster than the equivalent
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libgcc routines).</p>
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<p>
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All of the code in the compiler-rt project is available under the standard LLVM
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License, a "BSD-style" license. New in LLVM 2.8:
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Soft float support
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</p>
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</div>
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<!--=========================================================================-->
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<div class="doc_subsection">
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<a name="dragonegg">DragonEgg: llvm-gcc ported to gcc-4.5</a>
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</div>
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<div class="doc_text">
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<p>
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<a href="http://dragonegg.llvm.org/">DragonEgg</a> is a port of llvm-gcc to
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gcc-4.5. Unlike llvm-gcc, which makes many intrusive changes to the underlying
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gcc-4.2 code, dragonegg in theory does not require any gcc-4.5 modifications
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whatsoever (currently one small patch is needed). This is thanks to the new
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<a href="http://gcc.gnu.org/wiki/plugins">gcc plugin architecture</a>, which
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makes it possible to modify the behaviour of gcc at runtime by loading a plugin,
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which is nothing more than a dynamic library which conforms to the gcc plugin
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interface. DragonEgg is a gcc plugin that causes the LLVM optimizers to be run
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instead of the gcc optimizers, and the LLVM code generators instead of the gcc
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code generators, just like llvm-gcc. To use it, you add
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"-fplugin=path/dragonegg.so" to the gcc-4.5 command line, and gcc-4.5 magically
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becomes llvm-gcc-4.5!
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</p>
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<p>
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DragonEgg is still a work in progress. Currently C works very well, while C++,
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Ada and Fortran work fairly well. All other languages either don't work at all,
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or only work poorly. For the moment only the x86-32 and x86-64 targets are
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supported, and only on linux and darwin (darwin needs an additional gcc patch).
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</p>
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<p>
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2.8 status here.
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</p>
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</div>
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<!--=========================================================================-->
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<div class="doc_subsection">
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<a name="mc">llvm-mc: Machine Code Toolkit</a>
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</div>
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<div class="doc_text">
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<p>
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The LLVM Machine Code (aka MC) sub-project of LLVM was created to solve a number
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of problems in the realm of assembly, disassembly, object file format handling,
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and a number of other related areas that CPU instruction-set level tools work
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in. It is a sub-project of LLVM which provides it with a number of advantages
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over other compilers that do not have tightly integrated assembly-level tools.
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For a gentle introduction, please see the <a
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href="http://blog.llvm.org/2010/04/intro-to-llvm-mc-project.html">Intro to the
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LLVM MC Project Blog Post</a>.
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</p>
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<p>2.8 status here</p>
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</div>
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<!-- *********************************************************************** -->
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<div class="doc_section">
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<a name="externalproj">External Open Source Projects Using LLVM 2.8</a>
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</div>
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<!-- *********************************************************************** -->
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<div class="doc_text">
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<p>An exciting aspect of LLVM is that it is used as an enabling technology for
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a lot of other language and tools projects. This section lists some of the
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projects that have already been updated to work with LLVM 2.8.</p>
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</div>
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<!-- *********************************************************************** -->
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<div class="doc_section">
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<a name="whatsnew">What's New in LLVM 2.8?</a>
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</div>
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<!-- *********************************************************************** -->
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<div class="doc_text">
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<p>This release includes a huge number of bug fixes, performance tweaks and
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minor improvements. Some of the major improvements and new features are listed
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in this section.
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</p>
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</div>
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<!--=========================================================================-->
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<div class="doc_subsection">
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<a name="orgchanges">LLVM Community Changes</a>
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</div>
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<div class="doc_text">
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<p>In addition to changes to the code, between LLVM 2.7 and 2.8, a number of
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organization changes have happened:
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</p>
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<ul>
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</ul>
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</div>
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<!--=========================================================================-->
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<div class="doc_subsection">
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<a name="majorfeatures">Major New Features</a>
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</div>
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<div class="doc_text">
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<p>LLVM 2.8 includes several major new capabilities:</p>
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<ul>
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<li>.</li>
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</ul>
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</div>
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<!--=========================================================================-->
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<div class="doc_subsection">
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<a name="coreimprovements">LLVM IR and Core Improvements</a>
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</div>
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<div class="doc_text">
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<p>LLVM IR has several new features for better support of new targets and that
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expose new optimization opportunities:</p>
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<ul>
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<li>LLVM 2.8 changes the internal order of operands in <a
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href="http://llvm.org/doxygen/classllvm_1_1InvokeInst.html"><tt>InvokeInst</tt></a>
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and <a href="http://llvm.org/doxygen/classllvm_1_1CallInst.html"><tt>CallInst</tt></a>.
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To be portable across releases, resort to <tt>CallSite</tt> and the
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high-level accessors, such as <tt>getCalledValue</tt> and <tt>setUnwindDest</tt>.
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</li>
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<li>
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You can no longer pass use_iterators directly to cast<> (and similar), because
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these routines tend to perform costly dereference operations more than once. You
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have to dereference the iterators yourself and pass them in.
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</li>
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<li>
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llvm.memcpy.*, llvm.memset.*, llvm.memmove.* (and possibly other?) intrinsics
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take an extra parameter now (i1 isVolatile), totaling 5 parameters.
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If you were creating these intrinsic calls and prototypes yourself (as opposed
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to using Intrinsic::getDeclaration), you can use UpgradeIntrinsicFunction/UpgradeIntrinsicCall
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to be portable accross releases.
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Note that you cannot use Intrinsic::getDeclaration() in a backwards compatible
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way (needs 2/3 types now, in 2.7 it needed just 1).
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</li>
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<li>
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SetCurrentDebugLocation takes a DebugLoc now instead of a MDNode.
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Change your code to use
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SetCurrentDebugLocation(DebugLoc::getFromDILocation(...)).
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</li>
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<li>
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VISIBILITY_HIDDEN is gone.
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</li>
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<li>
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The <tt>RegisterPass</tt> and <tt>RegisterAnalysisGroup</tt> templates are
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considered deprecated, but continue to function in LLVM 2.8. Clients are
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strongly advised to use the upcoming <tt>INITIALIZE_PASS()</tt> and
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<tt>INITIALIZE_AG_PASS()</tt> macros instead.
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<li>
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SMDiagnostic takes different parameters now. //FIXME: how to upgrade?
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</li>
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<li>
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The constructor for the Triple class no longer tries to understand odd triple
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specifications. Frontends should ensure that they only pass valid triples to
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LLVM. The Triple::normalize utility method has been added to help front-ends
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deal with funky triples.
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<li>
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Some APIs got renamed:
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<ul>
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<li>llvm_report_error -> report_fatal_error</li>
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<li>llvm_install_error_handler -> install_fatal_error_handler</li>
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<li>llvm::DwarfExceptionHandling -> llvm::JITExceptionHandling</li>
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</ul>
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</li>
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</ul>
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</div>
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<!--=========================================================================-->
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<div class="doc_subsection">
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<a name="optimizer">Optimizer Improvements</a>
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</div>
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<div class="doc_text">
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<p>In addition to a large array of minor performance tweaks and bug fixes, this
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release includes a few major enhancements and additions to the optimizers:</p>
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<ul>
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<li></li>
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</ul>
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</div>
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<!--=========================================================================-->
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<div class="doc_subsection">
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<a name="executionengine">Interpreter and JIT Improvements</a>
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</div>
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<div class="doc_text">
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<ul>
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<li></li>
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</ul>
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</div>
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<!--=========================================================================-->
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<div class="doc_subsection">
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<a name="codegen">Target Independent Code Generator Improvements</a>
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</div>
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<div class="doc_text">
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<p>We have put a significant amount of work into the code generator
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infrastructure, which allows us to implement more aggressive algorithms and make
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it run faster:</p>
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<ul>
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<li>MachO writer works.</li>
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</ul>
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</div>
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<!--=========================================================================-->
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<div class="doc_subsection">
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<a name="x86">X86-32 and X86-64 Target Improvements</a>
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</div>
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<div class="doc_text">
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<p>New features of the X86 target include:
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</p>
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<ul>
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<li>The X86 backend now supports holding X87 floating point stack values
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in registers across basic blocks, dramatically improving performance of code
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that uses long double, and when targetting CPUs that don't support SSE.</li>
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</ul>
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</div>
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<!--=========================================================================-->
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<div class="doc_subsection">
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<a name="ARM">ARM Target Improvements</a>
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</div>
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<div class="doc_text">
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<p>New features of the ARM target include:
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</p>
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<ul>
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<li></li>
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</ul>
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</div>
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<!--=========================================================================-->
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<div class="doc_subsection">
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<a name="newapis">New Useful APIs</a>
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</div>
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<div class="doc_text">
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<p>This release includes a number of new APIs that are used internally, which
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may also be useful for external clients.
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</p>
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<ul>
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<li></li>
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</ul>
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</div>
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<!--=========================================================================-->
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<div class="doc_subsection">
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<a name="otherimprovements">Other Improvements and New Features</a>
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</div>
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<div class="doc_text">
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<p>Other miscellaneous features include:</p>
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<ul>
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<li></li>
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</ul>
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</div>
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<!--=========================================================================-->
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<div class="doc_subsection">
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<a name="changes">Major Changes and Removed Features</a>
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</div>
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<div class="doc_text">
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<p>If you're already an LLVM user or developer with out-of-tree changes based
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on LLVM 2.7, this section lists some "gotchas" that you may run into upgrading
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from the previous release.</p>
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<ul>
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<li>.ll file doesn't produce #uses comments anymore, to get them, run a .bc file
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through "llvm-dis --show-annotations".</li>
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<li>MSIL Backend removed.</li>
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<li>ABCD and SSI passes removed.</li>
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<li>'Union' LLVM IR feature removed.</li>
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</ul>
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<p>In addition, many APIs have changed in this release. Some of the major LLVM
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API changes are:</p>
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<ul>
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</ul>
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</div>
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<!-- *********************************************************************** -->
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<div class="doc_section">
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<a name="portability">Portability and Supported Platforms</a>
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</div>
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<!-- *********************************************************************** -->
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<div class="doc_text">
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<p>LLVM is known to work on the following platforms:</p>
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<ul>
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<li>Intel and AMD machines (IA32, X86-64, AMD64, EMT-64) running Red Hat
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Linux, Fedora Core, FreeBSD and AuroraUX (and probably other unix-like
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systems).</li>
|
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<li>PowerPC and X86-based Mac OS X systems, running 10.4 and above in 32-bit
|
|
and 64-bit modes.</li>
|
|
<li>Intel and AMD machines running on Win32 using MinGW libraries (native).</li>
|
|
<li>Intel and AMD machines running on Win32 with the Cygwin libraries (limited
|
|
support is available for native builds with Visual C++).</li>
|
|
<li>Sun x86 and AMD64 machines running Solaris 10, OpenSolaris 0906.</li>
|
|
<li>Alpha-based machines running Debian GNU/Linux.</li>
|
|
</ul>
|
|
|
|
<p>The core LLVM infrastructure uses GNU autoconf to adapt itself
|
|
to the machine and operating system on which it is built. However, minor
|
|
porting may be required to get LLVM to work on new platforms. We welcome your
|
|
portability patches and reports of successful builds or error messages.</p>
|
|
|
|
</div>
|
|
|
|
<!-- *********************************************************************** -->
|
|
<div class="doc_section">
|
|
<a name="knownproblems">Known Problems</a>
|
|
</div>
|
|
<!-- *********************************************************************** -->
|
|
|
|
<div class="doc_text">
|
|
|
|
<p>This section contains significant known problems with the LLVM system,
|
|
listed by component. If you run into a problem, please check the <a
|
|
href="http://llvm.org/bugs/">LLVM bug database</a> and submit a bug if
|
|
there isn't already one.</p>
|
|
|
|
<ul>
|
|
<li>LLVM will not correctly compile on Solaris and/or OpenSolaris
|
|
using the stock GCC 3.x.x series 'out the box',
|
|
See: <a href="GettingStarted.html#brokengcc">Broken versions of GCC and other tools</a>.
|
|
However, A <a href="http://pkg.auroraux.org/GCC">Modern GCC Build</a>
|
|
for x86/x86-64 has been made available from the third party AuroraUX Project
|
|
that has been meticulously tested for bootstrapping LLVM & Clang.</li>
|
|
<li>There have been reports of Solaris and/or OpenSolaris build failures due
|
|
to an incompatibility in the nm program as well. The nm from binutils does seem
|
|
to work.</li>
|
|
</ul>
|
|
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection">
|
|
<a name="experimental">Experimental features included with this release</a>
|
|
</div>
|
|
|
|
<div class="doc_text">
|
|
|
|
<p>The following components of this LLVM release are either untested, known to
|
|
be broken or unreliable, or are in early development. These components should
|
|
not be relied on, and bugs should not be filed against them, but they may be
|
|
useful to some people. In particular, if you would like to work on one of these
|
|
components, please contact us on the <a
|
|
href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev list</a>.</p>
|
|
|
|
<ul>
|
|
<li>The Alpha, SPU, MIPS, PIC16, Blackfin, MSP430, SystemZ and MicroBlaze
|
|
backends are experimental.</li>
|
|
<li><tt>llc</tt> "<tt>-filetype=asm</tt>" (the default) is the only
|
|
supported value for this option. XXX Update me</li>
|
|
</ul>
|
|
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection">
|
|
<a name="x86-be">Known problems with the X86 back-end</a>
|
|
</div>
|
|
|
|
<div class="doc_text">
|
|
|
|
<ul>
|
|
<li>The X86 backend does not yet support
|
|
all <a href="http://llvm.org/PR879">inline assembly that uses the X86
|
|
floating point stack</a>. It supports the 'f' and 't' constraints, but not
|
|
'u'.</li>
|
|
<li>Win64 code generation wasn't widely tested. Everything should work, but we
|
|
expect small issues to happen. Also, llvm-gcc cannot build the mingw64
|
|
runtime currently due to lack of support for the 'u' inline assembly
|
|
constraint and for X87 floating point inline assembly.</li>
|
|
<li>The X86-64 backend does not yet support the LLVM IR instruction
|
|
<tt>va_arg</tt>. Currently, front-ends support variadic
|
|
argument constructs on X86-64 by lowering them manually.</li>
|
|
</ul>
|
|
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection">
|
|
<a name="ppc-be">Known problems with the PowerPC back-end</a>
|
|
</div>
|
|
|
|
<div class="doc_text">
|
|
|
|
<ul>
|
|
<li>The Linux PPC32/ABI support needs testing for the interpreter and static
|
|
compilation, and lacks support for debug information.</li>
|
|
</ul>
|
|
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection">
|
|
<a name="arm-be">Known problems with the ARM back-end</a>
|
|
</div>
|
|
|
|
<div class="doc_text">
|
|
|
|
<ul>
|
|
<li>Thumb mode works only on ARMv6 or higher processors. On sub-ARMv6
|
|
processors, thumb programs can crash or produce wrong
|
|
results (<a href="http://llvm.org/PR1388">PR1388</a>).</li>
|
|
<li>Compilation for ARM Linux OABI (old ABI) is supported but not fully tested.
|
|
</li>
|
|
</ul>
|
|
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection">
|
|
<a name="sparc-be">Known problems with the SPARC back-end</a>
|
|
</div>
|
|
|
|
<div class="doc_text">
|
|
|
|
<ul>
|
|
<li>The SPARC backend only supports the 32-bit SPARC ABI (-m32); it does not
|
|
support the 64-bit SPARC ABI (-m64).</li>
|
|
</ul>
|
|
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection">
|
|
<a name="mips-be">Known problems with the MIPS back-end</a>
|
|
</div>
|
|
|
|
<div class="doc_text">
|
|
|
|
<ul>
|
|
<li>64-bit MIPS targets are not supported yet.</li>
|
|
</ul>
|
|
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection">
|
|
<a name="alpha-be">Known problems with the Alpha back-end</a>
|
|
</div>
|
|
|
|
<div class="doc_text">
|
|
|
|
<ul>
|
|
|
|
<li>On 21164s, some rare FP arithmetic sequences which may trap do not have the
|
|
appropriate nops inserted to ensure restartability.</li>
|
|
|
|
</ul>
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection">
|
|
<a name="c-be">Known problems with the C back-end</a>
|
|
</div>
|
|
|
|
<div class="doc_text">
|
|
|
|
<ul>
|
|
<li><a href="http://llvm.org/PR802">The C backend has only basic support for
|
|
inline assembly code</a>.</li>
|
|
<li><a href="http://llvm.org/PR1658">The C backend violates the ABI of common
|
|
C++ programs</a>, preventing intermixing between C++ compiled by the CBE and
|
|
C++ code compiled with <tt>llc</tt> or native compilers.</li>
|
|
<li>The C backend does not support all exception handling constructs.</li>
|
|
<li>The C backend does not support arbitrary precision integers.</li>
|
|
</ul>
|
|
|
|
</div>
|
|
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection">
|
|
<a name="c-fe">Known problems with the llvm-gcc C and C++ front-end</a>
|
|
</div>
|
|
|
|
<div class="doc_text">
|
|
|
|
<p>The only major language feature of GCC not supported by llvm-gcc is
|
|
the <tt>__builtin_apply</tt> family of builtins. However, some extensions
|
|
are only supported on some targets. For example, trampolines are only
|
|
supported on some targets (these are used when you take the address of a
|
|
nested function).</p>
|
|
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection">
|
|
<a name="fortran-fe">Known problems with the llvm-gcc Fortran front-end</a>
|
|
</div>
|
|
|
|
<div class="doc_text">
|
|
<ul>
|
|
<li>Fortran support generally works, but there are still several unresolved bugs
|
|
in <a href="http://llvm.org/bugs/">Bugzilla</a>. Please see the
|
|
tools/gfortran component for details.</li>
|
|
</ul>
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection">
|
|
<a name="ada-fe">Known problems with the llvm-gcc Ada front-end</a>
|
|
</div>
|
|
|
|
<div class="doc_text">
|
|
The llvm-gcc 4.2 Ada compiler works fairly well; however, this is not a mature
|
|
technology, and problems should be expected.
|
|
<ul>
|
|
<li>The Ada front-end currently only builds on X86-32. This is mainly due
|
|
to lack of trampoline support (pointers to nested functions) on other platforms.
|
|
However, it <a href="http://llvm.org/PR2006">also fails to build on X86-64</a>
|
|
which does support trampolines.</li>
|
|
<li>The Ada front-end <a href="http://llvm.org/PR2007">fails to bootstrap</a>.
|
|
This is due to lack of LLVM support for <tt>setjmp</tt>/<tt>longjmp</tt> style
|
|
exception handling, which is used internally by the compiler.
|
|
Workaround: configure with <tt>--disable-bootstrap</tt>.</li>
|
|
<li>The c380004, <a href="http://llvm.org/PR2010">c393010</a>
|
|
and <a href="http://llvm.org/PR2421">cxg2021</a> ACATS tests fail
|
|
(c380004 also fails with gcc-4.2 mainline).
|
|
If the compiler is built with checks disabled then <a href="http://llvm.org/PR2010">c393010</a>
|
|
causes the compiler to go into an infinite loop, using up all system memory.</li>
|
|
<li>Some GCC specific Ada tests continue to crash the compiler.</li>
|
|
<li>The <tt>-E</tt> binder option (exception backtraces)
|
|
<a href="http://llvm.org/PR1982">does not work</a> and will result in programs
|
|
crashing if an exception is raised. Workaround: do not use <tt>-E</tt>.</li>
|
|
<li>Only discrete types <a href="http://llvm.org/PR1981">are allowed to start
|
|
or finish at a non-byte offset</a> in a record. Workaround: do not pack records
|
|
or use representation clauses that result in a field of a non-discrete type
|
|
starting or finishing in the middle of a byte.</li>
|
|
<li>The <tt>lli</tt> interpreter <a href="http://llvm.org/PR2009">considers
|
|
'main' as generated by the Ada binder to be invalid</a>.
|
|
Workaround: hand edit the file to use pointers for <tt>argv</tt> and
|
|
<tt>envp</tt> rather than integers.</li>
|
|
<li>The <tt>-fstack-check</tt> option <a href="http://llvm.org/PR2008">is
|
|
ignored</a>.</li>
|
|
</ul>
|
|
</div>
|
|
|
|
<!-- *********************************************************************** -->
|
|
<div class="doc_section">
|
|
<a name="additionalinfo">Additional Information</a>
|
|
</div>
|
|
<!-- *********************************************************************** -->
|
|
|
|
<div class="doc_text">
|
|
|
|
<p>A wide variety of additional information is available on the <a
|
|
href="http://llvm.org">LLVM web page</a>, in particular in the <a
|
|
href="http://llvm.org/docs/">documentation</a> section. The web page also
|
|
contains versions of the API documentation which is up-to-date with the
|
|
Subversion version of the source code.
|
|
You can access versions of these documents specific to this release by going
|
|
into the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
|
|
|
|
<p>If you have any questions or comments about LLVM, please feel free to contact
|
|
us via the <a href="http://llvm.org/docs/#maillist"> mailing
|
|
lists</a>.</p>
|
|
|
|
</div>
|
|
|
|
<!-- *********************************************************************** -->
|
|
|
|
<hr>
|
|
<address>
|
|
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src="http://jigsaw.w3.org/css-validator/images/vcss-blue" alt="Valid CSS"></a>
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src="http://www.w3.org/Icons/valid-html401-blue" alt="Valid HTML 4.01"></a>
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|
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<a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br>
|
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Last modified: $Date$
|
|
</address>
|
|
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</body>
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</html>
|