<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
- <meta encoding="utf8">
<link rel="stylesheet" href="llvm.css" type="text/css">
- <title>LLVM 2.9 Release Notes</title>
+ <title>LLVM 3.0 Release Notes</title>
</head>
<body>
-<h1 class="doc_title">LLVM 2.9 Release Notes</h1>
+<h1>LLVM 3.0 Release Notes</h1>
<img align=right src="http://llvm.org/img/DragonSmall.png"
width="136" height="136" alt="LLVM Dragon Logo">
<ol>
<li><a href="#intro">Introduction</a></li>
<li><a href="#subproj">Sub-project Status Update</a></li>
- <li><a href="#externalproj">External Projects Using LLVM 2.9</a></li>
- <li><a href="#whatsnew">What's New in LLVM 2.9?</a></li>
+ <li><a href="#externalproj">External Projects Using LLVM 3.0</a></li>
+ <li><a href="#whatsnew">What's New in LLVM 3.0?</a></li>
<li><a href="GettingStarted.html">Installation Instructions</a></li>
<li><a href="#knownproblems">Known Problems</a></li>
<li><a href="#additionalinfo">Additional Information</a></li>
</ol>
<div class="doc_author">
- <p>Written by the <a href="http://llvm.org">LLVM Team</a></p>
+ <p>Written by the <a href="http://llvm.org/">LLVM Team</a></p>
</div>
<!--
-<h1 style="color:red">These are in-progress notes for the upcoming LLVM 2.9
+<h1 style="color:red">These are in-progress notes for the upcoming LLVM 3.0
release.<br>
You may prefer the
-<a href="http://llvm.org/releases/2.8/docs/ReleaseNotes.html">LLVM 2.8
+<a href="http://llvm.org/releases/2.9/docs/ReleaseNotes.html">LLVM 2.9
Release Notes</a>.</h1>
-->
<!-- *********************************************************************** -->
-<h1>
+<h2>
<a name="intro">Introduction</a>
-</h1>
+</h2>
<!-- *********************************************************************** -->
-<div class="doc_text">
+<div>
<p>This document contains the release notes for the LLVM Compiler
-Infrastructure, release 2.9. Here we describe the status of LLVM, including
-major improvements from the previous release and significant known problems.
-All LLVM releases may be downloaded from the <a
-href="http://llvm.org/releases/">LLVM releases web site</a>.</p>
+ Infrastructure, release 3.0. Here we describe the status of LLVM, including
+ major improvements from the previous release and significant known problems.
+ All LLVM releases may be downloaded from
+ the <a href="http://llvm.org/releases/">LLVM releases web site</a>.</p>
<p>For more information about LLVM, including information about the latest
-release, please check out the <a href="http://llvm.org/">main LLVM
-web site</a>. If you have questions or comments, the <a
-href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM Developer's
-Mailing List</a> is a good place to send them.</p>
+ release, please check out the <a href="http://llvm.org/">main LLVM web
+ site</a>. If you have questions or comments,
+ the <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM
+ Developer's Mailing List</a> is a good place to send them.</p>
-<p>Note that if you are reading this file from a Subversion checkout or the
-main LLVM web page, this document applies to the <i>next</i> release, not the
-current one. To see the release notes for a specific release, please see the
-<a href="http://llvm.org/releases/">releases page</a>.</p>
+<p>Note that if you are reading this file from a Subversion checkout or the main
+ LLVM web page, this document applies to the <i>next</i> release, not the
+ current one. To see the release notes for a specific release, please see the
+
<a href="http://llvm.org/releases/">releases page</a>.</p>
</div>
-->
<!-- *********************************************************************** -->
-<h1>
+<h2>
<a name="subproj">Sub-project Status Update</a>
-</h1>
+</h2>
<!-- *********************************************************************** -->
-<div class="doc_text">
-<p>
-The LLVM 2.9 distribution currently consists of code from the core LLVM
-repository (which roughly includes the LLVM optimizers, code generators
-and supporting tools), the Clang repository and the llvm-gcc repository. In
-addition to this code, the LLVM Project includes other sub-projects that are in
-development. Here we include updates on these subprojects.
-</p>
-
-</div>
+<div>
+<p>The LLVM 3.0 distribution currently consists of code from the core LLVM
+ repository (which roughly includes the LLVM optimizers, code generators and
+ supporting tools), the Clang repository and the llvm-gcc repository. In
+ addition to this code, the LLVM Project includes other sub-projects that are
+ in development. Here we include updates on these subprojects.</p>
<!--=========================================================================-->
-<h2>
+<h3>
<a name="clang">Clang: C/C++/Objective-C Frontend Toolkit</a>
-</h2>
+</h3>
-<div class="doc_text">
+<div>
<p><a href="http://clang.llvm.org/">Clang</a> is an LLVM front end for the C,
-C++, and Objective-C languages. Clang aims to provide a better user experience
-through expressive diagnostics, a high level of conformance to language
-standards, fast compilation, and low memory use. Like LLVM, Clang provides a
-modular, library-based architecture that makes it suitable for creating or
-integrating with other development tools. Clang is considered a
-production-quality compiler for C, Objective-C, C++ and Objective-C++ on x86
-(32- and 64-bit), and for darwin/arm targets.</p>
-
-<p>In the LLVM 2.9 time-frame, the Clang team has made many improvements in C,
-C++ and Objective-C support. C++ support is now generally rock solid, has
-been exercised on a broad variety of code, and has several new <a
-href="http://clang.llvm.org/cxx_status.html#cxx0x">C++'0x features</a>
-implemented (such as rvalue references and variadic templates). LLVM 2.9 has
-also brought in a large range of bug fixes and minor features (e.g. __label__
-support), and is much more compatible with the Linux Kernel.</p>
-
-<p>If Clang rejects your code but another compiler accepts it, please take a
-look at the <a href="http://clang.llvm.org/compatibility.html">language
-compatibility</a> guide to make sure this is not intentional or a known issue.
-</p>
+ C++, and Objective-C languages. Clang aims to provide a better user
+ experience through expressive diagnostics, a high level of conformance to
+ language standards, fast compilation, and low memory use. Like LLVM, Clang
+ provides a modular, library-based architecture that makes it suitable for
+ creating or integrating with other development tools. Clang is considered a
+ production-quality compiler for C, Objective-C, C++ and Objective-C++ on x86
+ (32- and 64-bit), and for darwin/arm targets.</p>
+
+<p>In the LLVM 3.0 time-frame, the Clang team has made many improvements:</p>
<ul>
+ <li>Greatly improved support for building C++ applications, with greater
+ stability and better diagnostics.</li>
+
+ <li><a href="http://clang.llvm.org/cxx_status.html">Improved support</a> for
+ the <a href="http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=50372">C++
+ 2011</a> standard, including implementations of non-static data member
+ initializers, alias templates, delegating constructors, the range-based
+ for loop, and implicitly-generated move constructors and move assignment
+ operators, among others.</li>
+
+ <li>Implemented support for some features of the upcoming C1x standard,
+ including static assertions and generic selections.</li>
+
+ <li>Better detection of include and linking paths for system headers and
+ libraries, especially for Linux distributions.</li>
+
+ <li>Implemented support
+ for <a href="http://clang.llvm.org/docs/AutomaticReferenceCounting.html">Automatic
+ Reference Counting</a> for Objective-C.</li>
+
+ <li>Implemented a number of optimizations in <tt>libclang</tt>, the Clang C
+ interface, to improve the performance of code completion and the mapping
+ from source locations to abstract syntax tree nodes.</li>
</ul>
+
+
+<p>If Clang rejects your code but another compiler accepts it, please take a
+ look at the <a href="http://clang.llvm.org/compatibility.html">language
+ compatibility</a> guide to make sure this is not intentional or a known
+ issue.</p>
+
</div>
<!--=========================================================================-->
-<h2>
+<h3>
<a name="dragonegg">DragonEgg: GCC front-ends, LLVM back-end</a>
-</h2>
+</h3>
-<div class="doc_text">
-<p>
-<a href="http://dragonegg.llvm.org/">DragonEgg</a> is a
-<a href="http://gcc.gnu.org/wiki/plugins">gcc plugin</a> that replaces GCC's
-optimizers and code generators with LLVM's.
-Currently it requires a patched version of gcc-4.5.
-The plugin can target the x86-32 and x86-64 processor families and has been
-used successfully on the Darwin, FreeBSD and Linux platforms.
-The Ada, C, C++ and Fortran languages work well.
-The plugin is capable of compiling plenty of Obj-C, Obj-C++ and Java but it is
-not known whether the compiled code actually works or not!
-</p>
+<div>
+<p><a href="http://dragonegg.llvm.org/">DragonEgg</a> is a
+ <a href="http://gcc.gnu.org/wiki/plugins">gcc plugin</a> that replaces GCC's
+ optimizers and code generators with LLVM's. Currently it requires a patched
+ version of gcc-4.5. The plugin can target the x86-32 and x86-64 processor
+ families and has been used successfully on the Darwin, FreeBSD and Linux
+ platforms. The Ada, C, C++ and Fortran languages work well. The plugin is
+ capable of compiling plenty of Obj-C, Obj-C++ and Java but it is not known
+ whether the compiled code actually works or not!</p>
+
+<p>The 3.0 release has the following notable changes:</p>
-<p>
-The 2.9 release has the following notable changes:
<ul>
-<li>The plugin is much more stable when compiling Fortran.</li>
-<li>Inline assembly where an asm output is tied to an input of a different size
-is now supported in many more cases.</li>
-<li>Basic support for the __float128 type was added. It is now possible to
-generate LLVM IR from programs using __float128 but code generation does not
-work yet.</li>
-<li>Compiling Java programs no longer systematically crashes the plugin.</li>
+<!--
+<li></li>
+-->
</ul>
</div>
<!--=========================================================================-->
-<h2>
+<h3>
<a name="compiler-rt">compiler-rt: Compiler Runtime Library</a>
-</h2>
+</h3>
-<div class="doc_text">
-<p>
-The new LLVM <a href="http://compiler-rt.llvm.org/">compiler-rt project</a>
-is a simple library that provides an implementation of the low-level
-target-specific hooks required by code generation and other runtime components.
-For example, when compiling for a 32-bit target, converting a double to a 64-bit
-unsigned integer is compiled into a runtime call to the "__fixunsdfdi"
-function. The compiler-rt library provides highly optimized implementations of
-this and other low-level routines (some are 3x faster than the equivalent
-libgcc routines).</p>
-
-<p>In the LLVM 2.9 timeframe, compiler_rt has had several minor changes for
- better ARM support, and a fairly major license change. All of the code in the
- compiler-rt project is now <a href="DeveloperPolicy.html#license">dual
- licensed</a> under MIT and UIUC license, which allows you to use compiler-rt
- in applications without the binary copyright reproduction clause. If you
- prefer the LLVM/UIUC license, you are free to continue using it under that
- license as well.</p>
+<div>
+
+<p>The new LLVM <a href="http://compiler-rt.llvm.org/">compiler-rt project</a>
+ is a simple library that provides an implementation of the low-level
+ target-specific hooks required by code generation and other runtime
+ components. For example, when compiling for a 32-bit target, converting a
+ double to a 64-bit unsigned integer is compiled into a runtime call to the
+ "__fixunsdfdi" function. The compiler-rt library provides highly optimized
+ implementations of this and other low-level routines (some are 3x faster than
+ the equivalent libgcc routines).</p>
+
+<p>In the LLVM 3.0 timeframe,</p>
</div>
<!--=========================================================================-->
-<h2>
+<h3>
<a name="lldb">LLDB: Low Level Debugger</a>
-</h2>
+</h3>
-<div class="doc_text">
-<p>
-<a href="http://lldb.llvm.org/">LLDB</a> is a brand new member of the LLVM
-umbrella of projects. LLDB is a next generation, high-performance debugger. It
-is built as a set of reusable components which highly leverage existing
-libraries in the larger LLVM Project, such as the Clang expression parser, the
-LLVM disassembler and the LLVM JIT.</p>
+<div>
-<p>
-LLDB is has advanced by leaps and bounds in the 2.9 timeframe. It is
-dramatically more stable and useful, and includes both a new <a
-href="http://lldb.llvm.org/tutorial.html">tutorial</a> and a <a
-href="http://lldb.llvm.org/lldb-gdb.html">side-by-side comparison with
-GDB</a>.</p>
+<p>LLDB has advanced by leaps and bounds in the 3.0 timeframe. It is
+ dramatically more stable and useful, and includes both a
+ new <a href="http://lldb.llvm.org/tutorial.html">tutorial</a> and
+ a <a href="http://lldb.llvm.org/lldb-gdb.html">side-by-side comparison with
+ GDB</a>.</p>
</div>
<!--=========================================================================-->
-<h2>
+<h3>
<a name="libc++">libc++: C++ Standard Library</a>
-</h2>
+</h3>
-<div class="doc_text">
-<p>
-<a href="http://libcxx.llvm.org/">libc++</a> is another new member of the LLVM
-family. It is an implementation of the C++ standard library, written from the
-ground up to specifically target the forthcoming C++'0X standard and focus on
-delivering great performance.</p>
+<div>
-<p>
-In the LLVM 2.9 timeframe, libc++ has had numerous bugs fixed, and is now being
-co-developed with Clang's C++'0x mode.</p>
-
-<p>
-Like compiler_rt, libc++ is now <a href="DeveloperPolicy.html#license">dual
- licensed</a> under the MIT and UIUC license, allowing it to be used more
- permissively.
-</p>
+<p>Like compiler_rt, libc++ is now <a href="DeveloperPolicy.html#license">dual
+ licensed</a> under the MIT and UIUC license, allowing it to be used more
+ permissively.</p>
</div>
<!--=========================================================================-->
-<h2>
+<h3>
<a name="LLBrowse">LLBrowse: IR Browser</a>
-</h2>
+</h3>
+
+<div>
+
+<p><a href="http://llvm.org/svn/llvm-project/llbrowse/trunk/doc/LLBrowse.html">
+ LLBrowse</a> is an interactive viewer for LLVM modules. It can load any LLVM
+ module and displays its contents as an expandable tree view, facilitating an
+ easy way to inspect types, functions, global variables, or metadata nodes. It
+ is fully cross-platform, being based on the popular wxWidgets GUI
+ toolkit.</p>
-<div class="doc_text">
-<p>
-<a href="http://llvm.org/svn/llvm-project/llbrowse/trunk/doc/LLBrowse.html">
- LLBrowse</a> is an interactive viewer for LLVM modules. It can load any LLVM
- module and displays its contents as an expandable tree view, facilitating an
- easy way to inspect types, functions, global variables, or metadata nodes. It
- is fully cross-platform, being based on the popular wxWidgets GUI toolkit.
-</p>
</div>
<!--=========================================================================-->
-<h2>
+<h3>
<a name="vmkit">VMKit</a>
-</h2>
+</h3>
+
+<div>
-<div class="doc_text">
<p>The <a href="http://vmkit.llvm.org/">VMKit project</a> is an implementation
- of a Java Virtual Machine (Java VM or JVM) that uses LLVM for static and
- just-in-time compilation. As of LLVM 2.9, VMKit now supports generational
- garbage collectors. The garbage collectors are provided by the MMTk framework,
- and VMKit can be configured to use one of the numerous implemented collectors
- of MMTk.
-</p>
+ of a Java Virtual Machine (Java VM or JVM) that uses LLVM for static and
+ just-in-time compilation. As of LLVM 3.0, VMKit now supports generational
+ garbage collectors. The garbage collectors are provided by the MMTk
+ framework, and VMKit can be configured to use one of the numerous implemented
+ collectors of MMTk.</p>
+
</div>
<!--=========================================================================-->
<!--
-<h2>
+<h3>
<a name="klee">KLEE: A Symbolic Execution Virtual Machine</a>
-</h2>
+</h3>
-<div class="doc_text">
+<div>
<p>
<a href="http://klee.llvm.org/">KLEE</a> is a symbolic execution framework for
programs in LLVM bitcode form. KLEE tries to symbolically evaluate "all" paths
<p>UPDATE!</p>
</div>-->
+</div>
<!-- *********************************************************************** -->
-<h1>
- <a name="externalproj">External Open Source Projects Using LLVM 2.9</a>
-</h1>
+<h2>
+ <a name="externalproj">External Open Source Projects Using LLVM 3.0</a>
+</h2>
<!-- *********************************************************************** -->
-<div class="doc_text">
+<div>
<p>An exciting aspect of LLVM is that it is used as an enabling technology for
a lot of other language and tools projects. This section lists some of the
- projects that have already been updated to work with LLVM 2.9.</p>
+ projects that have already been updated to work with LLVM 3.0.</p>
+
+<!--=========================================================================-->
+<h3>AddressSanitizer</h3>
+
+<div>
+
+<p><a href="http://code.google.com/p/address-sanitizer/">AddressSanitizer</a>
+ uses compiler instrumentation and a specialized malloc library to find C/C++
+ bugs such as use-after-free and out-of-bound accesses to heap, stack, and
+ globals. The key feature of the tool is speed: the average slowdown
+ introduced by AddressSanitizer is less than 2x.</p>
+
+</div>
+
+<!--=========================================================================-->
+<h3>ClamAV</h3>
+
+<div>
+
+<p><a href="http://www.clamav.net">Clam AntiVirus</a> is an open source (GPL)
+ anti-virus toolkit for UNIX, designed especially for e-mail scanning on mail
+ gateways.</p>
+
+<p>Since version 0.96 it
+ has <a href="http://vrt-sourcefire.blogspot.com/2010/09/introduction-to-clamavs-low-level.html">bytecode
+ signatures</a> that allow writing detections for complex malware.</p>
+
+<p>It uses LLVM's JIT to speed up the execution of bytecode on X86, X86-64,
+ PPC32/64, falling back to its own interpreter otherwise. The git version was
+ updated to work with LLVM 3.0.</p>
+
</div>
+<!--=========================================================================-->
+<h3>clReflect</h3>
+
+<div>
+
+<p><a href="https://bitbucket.org/dwilliamson/clreflect">clReflect</a> is a C++
+ parser that uses clang/LLVM to derive a light-weight reflection database
+ suitable for use in game development. It comes with a very simple runtime
+ library for loading and querying the database, requiring no external
+ dependencies (including CRT), and an additional utility library for object
+ management and serialisation.</p>
+
+</div>
<!--=========================================================================-->
-<h2>Crack Programming Language</h2>
+<!-- FIXME: Comment out
+<h3>Crack Programming Language</h3>
-<div class="doc_text">
+<div>
<p>
<a href="http://code.google.com/p/crack-language/">Crack</a> aims to provide the
ease of development of a scripting language with the performance of a compiled
language. The language derives concepts from C++, Java and Python, incorporating
object-oriented programming, operator overloading and strong typing.</p>
</div>
+-->
+<!--=========================================================================-->
+<h3>Glasgow Haskell Compiler (GHC)</h3>
+<div>
+
+<p>GHC is an open source, state-of-the-art programming suite for Haskell, a
+ standard lazy functional programming language. It includes an optimizing
+ static compiler generating good code for a variety of platforms, together
+ with an interactive system for convenient, quick development.</p>
+
+<p>GHC 7.0 and onwards include an LLVM code generator, supporting LLVM 2.8 and
+ later. Since LLVM 2.9, GHC now includes experimental support for the ARM
+ platform with LLVM 3.0.</p>
+
+</div>
+
+<!--=========================================================================-->
+<h3>gwXscript</h3>
+
+<div>
+
+<p><a href="http://botwars.tk/gwscript/">gwXscript</a> is an object oriented,
+ aspect oriented programming language which can create both executables (ELF,
+ EXE) and shared libraries (DLL, SO, DYNLIB). The compiler is implemented in
+ its own language and translates scripts into LLVM-IR which can be optimized
+ and translated into native code by the LLVM framework. Source code in
+ gwScript contains definitions that expand the namespaces. So you can build
+ your project and simply 'plug out' features by removing a file. The remaining
+ project does not leave scars since you directly separate concerns by the
+ 'template' feature of gwX. It is also possible to add new features to a
+ project by just adding files and without editing the original project. This
+ language is used for example to create games or content management systems
+ that should be extendable.</p>
+
+<p>gwXscript is strongly typed and offers comfort with its native types string,
+ hash and array. You can easily write new libraries in gwXscript or native
+ code. gwXscript is type safe and users should not be able to crash your
+ program or execute malicious code except code that is eating CPU time.</p>
+
+</div>
+
+<!--=========================================================================-->
+<h3>include-what-you-use</h3>
+
+<div>
+
+<p><a href="http://code.google.com/p/include-what-you-use">include-what-you-use</a>
+ is a tool to ensure that a file directly <code>#include</code>s
+ all <code>.h</code> files that provide a symbol that the file uses. It also
+ removes superfluous <code>#include</code>s from source files.</p>
+
+</div>
+
+<!--=========================================================================-->
+<h3>LanguageKit and Pragmatic Smalltalk</h3>
+
+<div>
+
+<p><a href="http://etoileos.com/etoile/features/languagekit/">LanguageKit</a> is
+ a framework for implementing dynamic languages sharing an object model with
+ Objective-C. It provides static and JIT compilation using LLVM along with
+ its own interpreter. Pragmatic Smalltalk is a dialect of Smalltalk, built on
+ top of LanguageKit, that interfaces directly with Objective-C, sharing the
+ same object representation and message sending behaviour. These projects are
+ developed as part of the Étoié desktop environment.</p>
+
+</div>
+
+<!--=========================================================================-->
+<h3>Mono</h3>
+
+<div>
+
+<p>An open source, cross-platform implementation of C# and the CLR that is
+ binary compatible with Microsoft.NET. Has an optional, dynamically-loaded
+ LLVM code generation backend in Mini, the JIT compiler.</p>
+
+<p>Note that we use a Git mirror of LLVM with some patches. See:
+ https://github.com/mono/llvm</p>
+
+</div>
+
<!--=========================================================================-->
-<h2>TTA-based Codesign Environment (TCE)</h2>
+<h3>Portable OpenCL (pocl)</h3>
+
+<div>
+
+<p>Portable OpenCL is an open source implementation of the OpenCL standard which
+ can be easily adapted for new targets. One of the goals of the project is
+ improving performance portability of OpenCL programs, avoiding the need for
+ target-dependent manual optimizations. A "native" target is included, which
+ allows running OpenCL kernels on the host (CPU).</p>
+
+</div>
+
+<!--=========================================================================-->
+<h3>Pure</h3>
-<div class="doc_text">
+<div>
+<p><a href="http://pure-lang.googlecode.com/">Pure</a> is an
+ algebraic/functional programming language based on term rewriting. Programs
+ are collections of equations which are used to evaluate expressions in a
+ symbolic fashion. The interpreter uses LLVM as a backend to JIT-compile Pure
+ programs to fast native code. Pure offers dynamic typing, eager and lazy
+ evaluation, lexical closures, a hygienic macro system (also based on term
+ rewriting), built-in list and matrix support (including list and matrix
+ comprehensions) and an easy-to-use interface to C and other programming
+ languages (including the ability to load LLVM bitcode modules, and inline C,
+ C++, Fortran and Faust code in Pure programs if the corresponding LLVM-enabled
+ compilers are installed).</p>
+
+<p>Pure version 0.48 has been tested and is known to work with LLVM 3.0
+ (and continues to work with older LLVM releases >= 2.5).</p>
+
+</div>
+
+<!--=========================================================================-->
+<h3>Renderscript</h3>
+
+<div>
+
+<p><a href="http://developer.android.com/guide/topics/renderscript/index.html">Renderscript</a>
+ is Android's advanced 3D graphics rendering and compute API. It provides a
+ portable C99-based language with extensions to facilitate common use cases
+ for enhancing graphics and thread level parallelism. The Renderscript
+ compiler frontend is based on Clang/LLVM. It emits a portable bitcode format
+ for the actual compiled script code, as well as reflects a Java interface for
+ developers to control the execution of the compiled bitcode. Executable
+ machine code is then generated from this bitcode by an LLVM backend on the
+ device. Renderscript is thus able to provide a mechanism by which Android
+ developers can improve performance of their applications while retaining
+ portability.</p>
+
+</div>
+
+<!--=========================================================================-->
+<h3>SAFECode</h3>
+
+<div>
+
+<p><a href="http://safecode.cs.illinois.edu">SAFECode</a> is a memory safe C/C++
+ compiler built using LLVM. It takes standard, unannotated C/C++ code,
+ analyzes the code to ensure that memory accesses and array indexing
+ operations are safe, and instruments the code with run-time checks when
+ safety cannot be proven statically. SAFECode can be used as a debugging aid
+ (like Valgrind) to find and repair memory safety bugs. It can also be used
+ to protect code from security attacks at run-time.</p>
+
+</div>
+
+<!--=========================================================================-->
+<h3>The Stupid D Compiler (SDC)</h3>
+
+<div>
+
+<p><a href="https://github.com/bhelyer/SDC">The Stupid D Compiler</a> is a
+ project seeking to write a self-hosting compiler for the D programming
+ language without using the frontend of the reference compiler (DMD).</p>
+
+</div>
+
+<!--=========================================================================-->
+<h3>TTA-based Co-design Environment (TCE)</h3>
+
+<div>
+
<p>TCE is a toolset for designing application-specific processors (ASP) based on
-the Transport triggered architecture (TTA). The toolset provides a complete
-co-design flow from C/C++ programs down to synthesizable VHDL and parallel
-program binaries. Processor customization points include the register files,
-function units, supported operations, and the interconnection network.</p>
+ the Transport triggered architecture (TTA). The toolset provides a complete
+ co-design flow from C/C++ programs down to synthesizable VHDL and parallel
+ program binaries. Processor customization points include the register files,
+ function units, supported operations, and the interconnection network.</p>
<p>TCE uses Clang and LLVM for C/C++ language support, target independent
-optimizations and also for parts of code generation. It generates new LLVM-based
-code generators "on the fly" for the designed TTA processors and loads them in
-to the compiler backend as runtime libraries to avoid per-target recompilation
-of larger parts of the compiler chain.</p>
+ optimizations and also for parts of code generation. It generates new
+ LLVM-based code generators "on the fly" for the designed TTA processors and
+ loads them in to the compiler backend as runtime libraries to avoid
+ per-target recompilation of larger parts of the compiler chain.</p>
+
</div>
+
+<!--=========================================================================-->
+<h3>Tart Programming Language</h3>
+
+<div>
+
+<p><a href="http://code.google.com/p/tart/">Tart</a> is a general-purpose,
+ strongly typed programming language designed for application
+ developers. Strongly inspired by Python and C#, Tart focuses on practical
+ solutions for the professional software developer, while avoiding the clutter
+ and boilerplate of legacy languages like Java and C++. Although Tart is still
+ in development, the current implementation supports many features expected of
+ a modern programming language, such as garbage collection, powerful
+ bidirectional type inference, a greatly simplified syntax for template
+ metaprogramming, closures and function literals, reflection, operator
+ overloading, explicit mutability and immutability, and much more. Tart is
+ flexible enough to accommodate a broad range of programming styles and
+ philosophies, while maintaining a strong commitment to simplicity, minimalism
+ and elegance in design.</p>
+</div>
-
<!--=========================================================================-->
-<h2>PinaVM</h2>
+<h3>ThreadSanitizer</h3>
+
+<div>
+
+<p><a href="http://code.google.com/p/data-race-test/">ThreadSanitizer</a> is a
+ data race detector for (mostly) C and C++ code, available for Linux, Mac OS
+ and Windows. On different systems, we use binary instrumentation frameworks
+ (Valgrind, Pin and DynamoRio) as frontends that generate the program events
+ for the race detection algorithm. On Linux, there's an option of using
+ LLVM-based compile-time instrumentation.</p>
+
+</div>
+
+<!--=========================================================================-->
+<h3>The ZooLib C++ Cross-Platform Application Framework</h3>
+
+<div>
+
+<p><a href="http://www.zoolib.org/">ZooLib</a> is Open Source under the MIT
+ License. It provides GUI, filesystem access, TCP networking, thread-safe
+ memory management, threading and locking for Mac OS X, Classic Mac OS,
+ Microsoft Windows, POSIX operating systems with X11, BeOS, Haiku, Apple's iOS
+ and Research in Motion's BlackBerry.</p>
+
+<p>My current work is to use CLang's static analyzer to improve ZooLib's code
+ quality. I also plan to set up LLVM compiles of the demo programs and test
+ programs using CLang and LLVM on all the platforms that CLang, LLVM and
+ ZooLib all support.</p>
+
+</div>
+
+<!--=========================================================================-->
+<!--
+<h3>PinaVM</h3>
-<div class="doc_text">
+<div>
<p><a href="http://gitorious.org/pinavm/pages/Home">PinaVM</a> is an open
source, <a href="http://www.systemc.org/">SystemC</a> front-end. Unlike many
other front-ends, PinaVM actually executes the elaboration of the
program analyzed using LLVM's JIT infrastructure. It later enriches the
bitcode with SystemC-specific information.</p>
</div>
+-->
-<!--=========================================================================-->
-<h2>Pure</h2>
-
-<div class="doc_text">
-<p><a href="http://pure-lang.googlecode.com/">Pure</a> is an
- algebraic/functional
- programming language based on term rewriting. Programs are collections
- of equations which are used to evaluate expressions in a symbolic
- fashion. The interpreter uses LLVM as a backend to JIT-compile Pure
- programs to fast native code. Pure offers dynamic typing, eager and lazy
- evaluation, lexical closures, a hygienic macro system (also based on
- term rewriting), built-in list and matrix support (including list and
- matrix comprehensions) and an easy-to-use interface to C and other
- programming languages (including the ability to load LLVM bitcode
- modules, and inline C, C++, Fortran and Faust code in Pure programs if
- the corresponding LLVM-enabled compilers are installed).</p>
-
-<p>Pure version 0.47 has been tested and is known to work with LLVM 2.9
- (and continues to work with older LLVM releases >= 2.5).</p>
-</div>
<!--=========================================================================-->
-<h2 id="icedtea">IcedTea Java Virtual Machine Implementation</h2>
+<!--
+<h3 id="icedtea">IcedTea Java Virtual Machine Implementation</h3>
-<div class="doc_text">
+<div>
<p>
<a href="http://icedtea.classpath.org/wiki/Main_Page">IcedTea</a> provides a
harness to build OpenJDK using only free software build tools and to provide
</p>
<p> OpenJDK 7 b112, IcedTea6 1.9 and IcedTea7 1.13 and later have been tested
-and are known to work with LLVM 2.9 (and continue to work with older LLVM
+and are known to work with LLVM 3.0 (and continue to work with older LLVM
releases >= 2.6 as well).</p>
</div>
+-->
<!--=========================================================================-->
-<h2>Glasgow Haskell Compiler (GHC)</h2>
-
-<div class="doc_text">
-<p>GHC is an open source, state-of-the-art programming suite for Haskell,
-a standard lazy functional programming language. It includes an
-optimizing static compiler generating good code for a variety of
-platforms, together with an interactive system for convenient, quick
-development.</p>
-
-<p>In addition to the existing C and native code generators, GHC 7.0 now
-supports an LLVM code generator. GHC supports LLVM 2.7 and later.</p>
-</div>
-
-<!--=========================================================================-->
-<h2>Polly - Polyhedral optimizations for LLVM</h2>
+<!--
+<h3>Polly - Polyhedral optimizations for LLVM</h3>
-<div class="doc_text">
+<div>
<p>Polly is a project that aims to provide advanced memory access optimizations
to better take advantage of SIMD units, cache hierarchies, multiple cores or
even vector accelerators for LLVM. Built around an abstract mathematical
Furthermore, Polly can use PoCC(Pluto) an advanced optimizer for data-locality
and parallelism.</p>
</div>
+-->
<!--=========================================================================-->
-<h2>Rubinius</h2>
+<!--
+<h3>Rubinius</h3>
-<div class="doc_text">
+<div>
<p><a href="http://github.com/evanphx/rubinius">Rubinius</a> is an environment
for running Ruby code which strives to write as much of the implementation in
Ruby as possible. Combined with a bytecode interpreting VM, it uses LLVM to
feedback, method inlining, and deoptimization are all used to remove dynamism
from ruby execution and increase performance.</p>
</div>
-
+-->
<!--=========================================================================-->
-<div class="doc_subsection">
+<!--
+<h3>
<a name="FAUST">FAUST Real-Time Audio Signal Processing Language</a>
-</div>
+</h3>
-<div class="doc_text">
+<div>
<p>
<a href="http://faust.grame.fr">FAUST</a> is a compiled language for real-time
audio signal processing. The name FAUST stands for Functional AUdio STream. Its
programming model combines two approaches: functional programming and block
diagram composition. In addition with the C, C++, JAVA output formats, the
-Faust compiler can now generate LLVM bitcode, and works with LLVM 2.7-2.9.</p>
+Faust compiler can now generate LLVM bitcode, and works with LLVM 2.7-3.0.</p>
</div>
+-->
+</div>
+
<!-- *********************************************************************** -->
-<h1>
- <a name="whatsnew">What's New in LLVM 2.9?</a>
-</h1>
+<h2>
+ <a name="whatsnew">What's New in LLVM 3.0?</a>
+</h2>
<!-- *********************************************************************** -->
-<div class="doc_text">
+<div>
<p>This release includes a huge number of bug fixes, performance tweaks and
-minor improvements. Some of the major improvements and new features are listed
-in this section.
-</p>
-
-</div>
+ minor improvements. Some of the major improvements and new features are
+ listed in this section.</p>
<!--=========================================================================-->
-<h2>
+<h3>
<a name="majorfeatures">Major New Features</a>
-</h2>
+</h3>
-<div class="doc_text">
+<div>
-<p>LLVM 2.9 includes several major new capabilities:</p>
+<p>LLVM 3.0 includes several major new capabilities:</p>
<ul>
-
-<li>Type Based Alias Analysis (TBAA) is now implemented and turned on by default
- in Clang. This allows substantially better load/store optimization in some
- cases. TBAA can be disabled by passing -fno-strict-aliasing.
-</li>
-<li>This release has seen a continued focus on quality of debug information.
- LLVM now generates much higher fidelity debug information, particularly when
- debugging optimized code.</li>
-
-<li>Inline assembly now supports multiple alternative constraints.</li>
-
-<li>A new backend for the NVIDIA PTX virtual ISA (used to target its GPUs) is
- under rapid development. It is not generally useful in 2.9, but is making
- rapid progress.</li>
+<!--
+<li></li>
+-->
</ul>
</div>
<!--=========================================================================-->
-<h2>
+<h3>
<a name="coreimprovements">LLVM IR and Core Improvements</a>
-</h2>
+</h3>
+
+<div>
-<div class="doc_text">
<p>LLVM IR has several new features for better support of new targets and that
-expose new optimization opportunities:</p>
+ expose new optimization opportunities:</p>
+
+<p>One of the biggest changes is that 3.0 has a new exception handling
+ system. The old system used LLVM intrinsics to convey the exception handling
+ information to the code generator. It worked in most cases, but not
+ all. Inlining was especially difficult to get right. Also, the intrinsics
+ could be moved away from the <code>invoke</code> instruction, making it hard
+ to recover that information.</p>
+
+<p>The new EH system makes exception handling a first-class member of the IR. It
+ adds two new instructions:</p>
<ul>
-<li>The <a href="LangRef.html#bitwiseops">udiv, ashr, lshr, and shl</a>
- instructions now have support exact and nuw/nsw bits to indicate that they
- don't overflow or shift out bits. This is useful for optimization of <a
- href="http://llvm.org/PR8862">pointer differences</a> and other cases.</li>
-
-<li>LLVM IR now supports the <a href="LangRef.html#globalvars">unnamed_addr</a>
- attribute to indicate that constant global variables with identical
- initializers can be merged. This fixed <a href="http://llvm.org/PR8927">an
- issue</a> where LLVM would incorrectly merge two globals which were supposed
- to have distinct addresses.</li>
-
-<li>The new <a href="LangRef.html#fnattrs">hotpatch attribute</a> has been added
- to allow runtime patching of functions.</li>
+ <li><a href="LangRef.html#i_landingpad"><code>landingpad</code></a> —
+ this instruction defines a landing pad basic block. It contains all of the
+ information that's needed by the code generator. It's also required to be
+ the first non-PHI instruction in the landing pad. In addition, a landing
+ pad may be jumped to only by the unwind edge of an <code>invoke</code>
+ instruction.</li>
+
+ <li><a href="LangRef.html#i_resume"><code>resume</code></a> — this
+ instruction causes the current exception to resume traveling up the
+ stack. It replaces the <code>@llvm.eh.resume</code> intrinsic.</li>
</ul>
+<p>Converting from the old EH API to the new EH API is rather simple, because a
+ lot of complexity has been removed. The two intrinsics,
+ <code>@llvm.eh.exception</code> and <code>@llvm.eh.selector</code> have been
+ superceded by the <code>landingpad</code> instruction. Instead of generating
+ a call to <code>@llvm.eh.exception</code> and <code>@llvm.eh.selector</code>:
+
+<div class="doc_code">
+<pre>
+Function *ExcIntr = Intrinsic::getDeclaration(TheModule,
+ Intrinsic::eh_exception);
+Function *SlctrIntr = Intrinsic::getDeclaration(TheModule,
+ Intrinsic::eh_selector);
+
+// The exception pointer.
+Value *ExnPtr = Builder.CreateCall(ExcIntr, "exc_ptr");
+
+std::vector<Value*> Args;
+Args.push_back(ExnPtr);
+Args.push_back(Builder.CreateBitCast(Personality,
+ Type::getInt8PtrTy(Context)));
+
+<i>// Add selector clauses to Args.</i>
+
+// The selector call.
+Builder.CreateCall(SlctrIntr, Args, "exc_sel");
+</pre>
+</div>
+
+<p>You should instead generate a <code>landingpad</code> instruction, that
+ returns an exception object and selector value:</p>
+
+<div class="doc_code">
+<pre>
+LandingPadInst *LPadInst =
+ Builder.CreateLandingPad(StructType::get(Int8PtrTy, Int32Ty, NULL),
+ Personality, 0);
+
+Value *LPadExn = Builder.CreateExtractValue(LPadInst, 0);
+Builder.CreateStore(LPadExn, getExceptionSlot());
+
+Value *LPadSel = Builder.CreateExtractValue(LPadInst, 1);
+Builder.CreateStore(LPadSel, getEHSelectorSlot());
+</pre>
+</div>
+
+<p>It's now trivial to add the individual clauses to the <code>landingpad</code>
+ instruction.</p>
+
+<div class="doc_code">
+<pre>
+<i><b>// Adding a catch clause</b></i>
+Constant *TypeInfo = getTypeInfo();
+LPadInst->addClause(TypeInfo);
+
+<i><b>// Adding a C++ catch-all</b></i>
+LPadInst->addClause(Constant::getNullValue(Builder.getInt8PtrTy()));
+
+<i><b>// Adding a cleanup</b></i>
+LPadInst->setCleanup(true);
+
+<i><b>// Adding a filter clause</b></i>
+std::vector<Constant*> TypeInfos;
+Constant *TypeInfo = getFilterTypeInfo();
+TypeInfos.push_back(Builder.CreateBitCast(TypeInfo, Builder.getInt8PtrTy()));
+
+ArrayType *FilterTy = ArrayType::get(Int8PtrTy, TypeInfos.size());
+LPadInst->addClause(ConstantArray::get(FilterTy, TypeInfos));
+</pre>
+</div>
+
+<p>Converting from using the <code>@llvm.eh.resume</code> intrinsic to
+ the <code>resume</code> instruction is trivial. It takes the exception
+ pointer and exception selector values returned by
+ the <code>landingpad</code> instruction:</p>
+
+<div class="doc_code">
+<pre>
+Type *UnwindDataTy = StructType::get(Builder.getInt8PtrTy(),
+ Builder.getInt32Ty(), NULL);
+Value *UnwindData = UndefValue::get(UnwindDataTy);
+Value *ExcPtr = Builder.CreateLoad(getExceptionObjSlot());
+Value *ExcSel = Builder.CreateLoad(getExceptionSelSlot());
+UnwindData = Builder.CreateInsertValue(UnwindData, ExcPtr, 0, "exc_ptr");
+UnwindData = Builder.CreateInsertValue(UnwindData, ExcSel, 1, "exc_sel");
+Builder.CreateResume(UnwindData);
+</pre>
+</div>
+
</div>
<!--=========================================================================-->
-<h2>
+<h3>
<a name="optimizer">Optimizer Improvements</a>
-</h2>
+</h3>
-<div class="doc_text">
+<div>
<p>In addition to a large array of minor performance tweaks and bug fixes, this
-release includes a few major enhancements and additions to the optimizers:</p>
+ release includes a few major enhancements and additions to the
+ optimizers:</p>
<ul>
-<li>Link Time Optimization (LTO) has been improved to use MC for parsing inline
- assembly and now can build large programs like Firefox 4 on both Mac OS X and
- Linux.</li>
-
-<li>The new -loop-idiom pass recognizes memset/memcpy loops (and memset_pattern
- on darwin), turning them into library calls, which are typically better
- optimized than inline code. If you are building a libc and notice that your
- memcpy and memset functions are compiled into infinite recursion, please build
- with -ffreestanding or -fno-builtin to disable this pass.</li>
-
-<li>A new -early-cse pass does a fast pass over functions to fold constants,
- simplify expressions, perform simple dead store elimination, and perform
- common subexpression elimination. It does a good job at catching some of the
- trivial redundancies that exist in unoptimized code, making later passes more
- effective.</li>
-
-<li>A new -loop-instsimplify pass is used to clean up loop bodies in the loop
- optimizer.</li>
-
-<li>The new TargetLibraryInfo interface allows mid-level optimizations to know
- whether the current target's runtime library has certain functions. For
- example, the optimizer can now transform integer-only printf calls to call
- iprintf, allowing reduced code size for embedded C libraries (e.g. newlib).
-</li>
-
-<li>LLVM has a new <a href="WritingAnLLVMPass.html#RegionPass">RegionPass</a>
- infrastructure for region-based optimizations.</li>
-
-<li>Several optimizer passes have been substantially sped up:
- GVN is much faster on functions with deep dominator trees and lots of basic
- blocks. The dominator tree and dominance frontier passes are much faster to
- compute, and preserved by more passes (so they are computed less often). The
- -scalar-repl pass is also much faster and doesn't use DominanceFrontier.
-</li>
-
-<li>The Dead Store Elimination pass is more aggressive optimizing stores of
- different types: e.g. a large store following a small one to the same address.
- The MemCpyOptimizer pass handles several new forms of memcpy elimination.</li>
-
-<li>LLVM now optimizes various idioms for overflow detection into check of the
- flag register on various CPUs. For example, we now compile:
-
- <pre>
- unsigned long t = a+b;
- if (t < a) ...
- </pre>
- into:
- <pre>
- addq %rdi, %rbx
- jno LBB0_2
- </pre>
+<!--
+<li></li>
+-->
</li>
</ul>
</div>
<!--=========================================================================-->
-<h2>
+<h3>
<a name="mc">MC Level Improvements</a>
-</h2>
+</h3>
-<div class="doc_text">
-<p>
-The LLVM Machine Code (aka MC) subsystem was created to solve a number
-of problems in the realm of assembly, disassembly, object file format handling,
-and a number of other related areas that CPU instruction-set level tools work
-in.</p>
-
-<ul>
-<li>ELF MC support has matured enough for the integrated assembler to be turned
- on by default in Clang on X86-32 and X86-64 ELF systems.</li>
-
-<li>MC supports and CodeGen uses the <tt>.file</tt> and <tt>.loc</tt> directives
- for producing line number debug info. This produces more compact line
- tables and easier to read .s files.</li>
-
-<li>MC supports the <tt>.cfi_*</tt> directives for producing DWARF
- frame information, but it is still not used by CodeGen by default.</li>
+<div>
-
-<li>The MC assembler now generates much better diagnostics for common errors,
- is much faster at matching instructions, is much more bug-compatible with
- the GAS assembler, and is now generally useful for a broad range of X86
- assembly.</li>
-
-<li>We now have some basic <a href="CodeGenerator.html#mc">internals
- documentation</a> for MC.</li>
-
-<li>.td files can now specify assembler aliases directly with the <a
- href="CodeGenerator.html#na_instparsing">MnemonicAlias and InstAlias</a>
- tblgen classes.</li>
-
-<li>LLVM now has an experimental format-independent object file manipulation
- library (lib/Object). It supports both PE/COFF and ELF. The llvm-nm tool has
- been extended to work with native object files, and the new llvm-objdump tool
- supports disassembly of object files (but no relocations are displayed yet).
-</li>
-
-<li>Win32 PE-COFF support in the MC assembler has made a lot of progress in the
- 2.9 timeframe, but is still not generally useful.</li>
+<p>The LLVM Machine Code (aka MC) subsystem was created to solve a number of
+ problems in the realm of assembly, disassembly, object file format handling,
+ and a number of other related areas that CPU instruction-set level tools work
+ in.</p>
+<ul>
+<!--
+<li></li>
+-->
</ul>
-<p>For more information, please see the <a
-href="http://blog.llvm.org/2010/04/intro-to-llvm-mc-project.html">Intro to the
-LLVM MC Project Blog Post</a>.
-</p>
+<p>For more information, please see
+ the <a href="http://blog.llvm.org/2010/04/intro-to-llvm-mc-project.html">Intro
+ to the LLVM MC Project Blog Post</a>.</p>
</div>
<!--=========================================================================-->
-<h2>
+<h3>
<a name="codegen">Target Independent Code Generator Improvements</a>
-</h2>
+</h3>
-<div class="doc_text">
+<div>
<p>We have put a significant amount of work into the code generator
-infrastructure, which allows us to implement more aggressive algorithms and make
-it run faster:</p>
+ infrastructure, which allows us to implement more aggressive algorithms and
+ make it run faster:</p>
<ul>
-<li>The pre-register-allocation (preRA) instruction scheduler models register
- pressure much more accurately in some cases. This allows the adoption of more
- aggressive scheduling heuristics without causing spills to be generated.
-</li>
-
-<li>LiveDebugVariables is a new pass that keeps track of debugging information
- for user variables that are promoted to registers in optimized builds.</li>
-
-<li>The scheduler now models operand latency and pipeline forwarding.</li>
-
-<li>A major register allocator infrastructure rewrite is underway. It is not on
- by default for 2.9 and you are not advised to use it, but it has made
- substantial progress in the 2.9 timeframe:
- <ul>
- <li>A new -regalloc=basic "basic" register allocator can be used as a simple
- fallback when debugging. It uses the new infrastructure.</li>
- <li>New infrastructure is in place for live range splitting. "SplitKit" can
- break a live interval into smaller pieces while preserving SSA form, and
- SpillPlacement can help find the best split points. This is a work in
- progress so the API is changing quickly.</li>
- <li>The inline spiller has learned to clean up after live range splitting. It
- can hoist spills out of loops, and it can eliminate redundant spills.</li>
- <li>Rematerialization works with live range splitting.</li>
- <li>The new "greedy" register allocator using live range splitting. This will
- be the default register allocator in the next LLVM release, but it is not
- turned on by default in 2.9.</li>
- </ul>
-</li>
+<!--
+<li></li>
+-->
</ul>
</div>
<!--=========================================================================-->
-<h2>
+<h3>
<a name="x86">X86-32 and X86-64 Target Improvements</a>
-</h2>
+</h3>
-<div class="doc_text">
-<p>New features and major changes in the X86 target include:
-</p>
+<div>
+
+<p>New features and major changes in the X86 target include:</p>
<ul>
-<li>LLVM 2.9 includes a complete reimplementation of the MMX instruction set.
- The reimplementation uses a new LLVM IR <a
- href="LangRef.html#t_x86mmx">x86_mmx</a> type to ensure that MMX operations
- are <em>only</em> generated from source that uses MMX builtin operations. With
- this, random types like <2 x i32> are not turned into MMX operations
- (which can be catastrophic without proper "emms" insertion). Because the X86
- code generator always generates reliable code, the -disable-mmx flag is now
- removed.
-</li>
-
-<li>X86 support for FS/GS relative loads and stores using <a
- href="CodeGenerator.html#x86_memory">address space 256/257</a> works reliably
- now.</li>
-
-<li>LLVM 2.9 generates much better code in several cases by using adc/sbb to
- avoid generation of conditional move instructions for conditional increment
- and other idioms.</li>
-<li>The X86 backend has adopted a new preRA scheduling mode, "list-ilp", to
- shorten the height of instruction schedules without inducing register spills.
-</li>
+ <li>The CRC32 intrinsics have been renamed. The intrinsics were previously
+ <code>@llvm.x86.sse42.crc32.[8|16|32]</code>
+ and <code>@llvm.x86.sse42.crc64.[8|64]</code>. They have been renamed to
+ <code>@llvm.x86.sse42.crc32.32.[8|16|32]</code> and
+ <code>@llvm.x86.sse42.crc32.64.[8|64]</code>.</li>
-<li>The MC assembler supports 3dNow! and 3DNowA instructions.</li>
-
-<li>Several bugs have been fixed for Windows x64 code generator.</li>
</ul>
</div>
<!--=========================================================================-->
-<h2>
+<h3>
<a name="ARM">ARM Target Improvements</a>
-</h2>
+</h3>
-<div class="doc_text">
-<p>New features of the ARM target include:
-</p>
-
-<ul>
-<li>The ARM backend now has a fast instruction selector, which dramatically
- improves -O0 compile times.</li>
-<li>The ARM backend has new tuning for Cortex-A8 and Cortex-A9 CPUs.</li>
-<li>The __builtin_prefetch builtin (and llvm.prefetch intrinsic) is compiled
- into prefetch instructions instead of being discarded.</li>
+<div>
-<li> The ARM backend preRA scheduler now models machine resources at cycle
- granularity. This allows the scheduler to both accurately model
- instruction latency and avoid overcommitting functional units.</li>
+<p>New features of the ARM target include:</p>
-<li>Countless ARM microoptimizations have landed in LLVM 2.9.</li>
+<ul>
+<!--
+<li></li>
+-->
</ul>
</div>
<!--=========================================================================-->
-<h2>
+<h3>
<a name="OtherTS">Other Target Specific Improvements</a>
-</h2>
-
-<div class="doc_text">
-<ul>
-<li>MicroBlaze: major updates for aggressive delay slot filler, MC-based
- assembly printing, assembly instruction parsing, ELF .o file emission, and MC
- instruction disassembler have landed.</li>
+</h3>
-<li>SPARC: Many improvements, including using the Y registers for
- multiplications and addition of a simple delay slot filler.</li>
+<div>
-<li>PowerPC: The backend has been largely MC'ized and is ready to support
- directly writing out mach-o object files. No one seems interested in finishing
- this final step though.</li>
-
+<ul>
+<!--
+<li></li>
+-->
</ul>
+
</div>
<!--=========================================================================-->
-<h2>
+<h3>
<a name="changes">Major Changes and Removed Features</a>
-</h2>
+</h3>
-<div class="doc_text">
+<div>
-<p>If you're already an LLVM user or developer with out-of-tree changes based
-on LLVM 2.8, this section lists some "gotchas" that you may run into upgrading
-from the previous release.</p>
+<p>If you're already an LLVM user or developer with out-of-tree changes based on
+ LLVM 2.9, this section lists some "gotchas" that you may run into upgrading
+ from the previous release.</p>
<ul>
-<li><b>This is the last release to support the llvm-gcc frontend.</b></li>
-
-<li>LLVM has a new <a href="CodingStandards.html#ll_naming">naming
- convention standard</a>, though the codebase hasn't fully adopted it yet.</li>
-
-<li>The new DIBuilder class provides a simpler interface for front ends to
- encode debug info in LLVM IR, and has replaced DIFactory.</li>
-
-<li>LLVM IR and other tools always work on normalized target triples (which have
- been run through <tt>Triple::normalize</tt>).</li>
+ <li>The <code>LLVMC</code> front end code was removed while separating
+ out language independence.</li>
+ <li>The <code>LowerSetJmp</code> pass wasn't used effectively by any
+ target and has been removed.</li>
+ <li>The old <code>TailDup</code> pass was not used in the standard pipeline
+ and was unable to update ssa form, so it has been removed.
+ <li>The syntax of volatile loads and stores in IR has been changed to
+ "<code>load volatile</code>"/"<code>store volatile</code>". The old
+ syntax ("<code>volatile load</code>"/"<code>volatile store</code>")
+ is still accepted, but is now considered deprecated.</li>
+ <li>The old atomic intrinscs (<code>llvm.memory.barrier</code> and
+ <code>llvm.atomic.*</code>) are now gone. Please use the new atomic
+ instructions, described in the <a href="Atomics.html">atomics guide</a>.
+</ul>
-<li>The target triple x86_64--mingw64 is obsoleted. Use x86_64--mingw32
- instead.</li>
+<h4>Windows (32-bit)</h4>
+<div>
-<li>The PointerTracking pass has been removed from mainline, and moved to The
- ClamAV project (its only client).</li>
-
-<li>The LoopIndexSplit, LiveValues, SimplifyHalfPowrLibCalls, GEPSplitter, and
- PartialSpecialization passes were removed. They were unmaintained,
- buggy, or deemed to be a bad idea.</li>
+<ul>
+ <li>On Win32(MinGW32 and MSVC), Windows 2000 will not be supported.
+ Windows XP or higher is required.</li>
</ul>
</div>
+</div>
+
<!--=========================================================================-->
-<h2>
+<h3>
<a name="api_changes">Internal API Changes</a>
-</h2>
+</h3>
-<div class="doc_text">
+<div>
<p>In addition, many APIs have changed in this release. Some of the major
- LLVM API changes are:</p>
+ LLVM API changes are:</p>
<ul>
-<li>include/llvm/System merged into include/llvm/Support.</li>
-<li>The <a href="http://llvm.org/PR5207">llvm::APInt API</a> was significantly
- cleaned up.</li>
-
-<li>In the code generator, MVT::Flag was renamed to MVT::Glue to more accurately
- describe its behavior.</li>
-
-<li>The system_error header from C++0x was added, and is now pervasively used to
- capture and handle i/o and other errors in LLVM.</li>
+ <li>The biggest and most pervasive change is that llvm::Type's are no longer
+ returned or accepted as 'const' values. Instead, just pass around
+ non-const Type's.</li>
-<li>The old sys::Path API has been deprecated in favor of the new PathV2 API,
- which is more efficient and flexible.</li>
+ <li><code>PHINode::reserveOperandSpace</code> has been removed. Instead, you
+ must specify how many operands to reserve space for when you create the
+ PHINode, by passing an extra argument
+ into <code>PHINode::Create</code>.</li>
+
+ <li>PHINodes no longer store their incoming BasicBlocks as operands. Instead,
+ the list of incoming BasicBlocks is stored separately, and can be accessed
+ with new functions <code>PHINode::block_begin</code>
+ and <code>PHINode::block_end</code>.</li>
+
+ <li>Various functions now take an <code>ArrayRef</code> instead of either a
+ pair of pointers (or iterators) to the beginning and end of a range, or a
+ pointer and a length. Others now return an <code>ArrayRef</code> instead
+ of a reference to a <code>SmallVector</code>
+ or <code>std::vector</code>. These include:
+<ul>
+<!-- Please keep this list sorted. -->
+<li><code>CallInst::Create</code></li>
+<li><code>ComputeLinearIndex</code> (in <code>llvm/CodeGen/Analysis.h</code>)</li>
+<li><code>ConstantArray::get</code></li>
+<li><code>ConstantExpr::getExtractElement</code></li>
+<li><code>ConstantExpr::getGetElementPtr</code></li>
+<li><code>ConstantExpr::getInBoundsGetElementPtr</code></li>
+<li><code>ConstantExpr::getIndices</code></li>
+<li><code>ConstantExpr::getInsertElement</code></li>
+<li><code>ConstantExpr::getWithOperands</code></li>
+<li><code>ConstantFoldCall</code> (in <code>llvm/Analysis/ConstantFolding.h</code>)</li>
+<li><code>ConstantFoldInstOperands</code> (in <code>llvm/Analysis/ConstantFolding.h</code>)</li>
+<li><code>ConstantVector::get</code></li>
+<li><code>DIBuilder::createComplexVariable</code></li>
+<li><code>DIBuilder::getOrCreateArray</code></li>
+<li><code>ExtractValueInst::Create</code></li>
+<li><code>ExtractValueInst::getIndexedType</code></li>
+<li><code>ExtractValueInst::getIndices</code></li>
+<li><code>FindInsertedValue</code> (in <code>llvm/Analysis/ValueTracking.h</code>)</li>
+<li><code>gep_type_begin</code> (in <code>llvm/Support/GetElementPtrTypeIterator.h</code>)</li>
+<li><code>gep_type_end</code> (in <code>llvm/Support/GetElementPtrTypeIterator.h</code>)</li>
+<li><code>GetElementPtrInst::Create</code></li>
+<li><code>GetElementPtrInst::CreateInBounds</code></li>
+<li><code>GetElementPtrInst::getIndexedType</code></li>
+<li><code>InsertValueInst::Create</code></li>
+<li><code>InsertValueInst::getIndices</code></li>
+<li><code>InvokeInst::Create</code></li>
+<li><code>IRBuilder::CreateCall</code></li>
+<li><code>IRBuilder::CreateExtractValue</code></li>
+<li><code>IRBuilder::CreateGEP</code></li>
+<li><code>IRBuilder::CreateInBoundsGEP</code></li>
+<li><code>IRBuilder::CreateInsertValue</code></li>
+<li><code>IRBuilder::CreateInvoke</code></li>
+<li><code>MDNode::get</code></li>
+<li><code>MDNode::getIfExists</code></li>
+<li><code>MDNode::getTemporary</code></li>
+<li><code>MDNode::getWhenValsUnresolved</code></li>
+<li><code>SimplifyGEPInst</code> (in <code>llvm/Analysis/InstructionSimplify.h</code>)</li>
+<li><code>TargetData::getIndexedOffset</code></li>
+</ul></li>
+
+ <li>All forms of <code>StringMap::getOrCreateValue</code> have been remove
+ except for the one which takes a <code>StringRef</code>.</li>
+
+ <li>The <code>LLVMBuildUnwind</code> function from the C API was removed. The
+ LLVM <code>unwind</code> instruction has been deprecated for a long time
+ and isn't used by the current front-ends. So this was removed during the
+ exception handling rewrite.</li>
+
+ <li>The <code>LLVMAddLowerSetJmpPass</code> function from the C API was
+ removed because the <code>LowerSetJmp</code> pass was removed.</li>
+
+ <li>The <code>DIBuilder</code> interface used by front ends to encode
+ debugging information in the LLVM IR now expects clients to
+ use <code>DIBuilder::finalize()</code> at the end of translation unit to
+ complete debugging information encoding.</li>
+
+ <li>The way the type system works has been
+ rewritten: <code>PATypeHolder</code> and <code>OpaqueType</code> are gone,
+ and all APIs deal with <code>Type*</code> instead of <code>const
+ Type*</code>. If you need to create recursive structures, then create a
+ named structure, and use <code>setBody()</code> when all its elements are
+ built. Type merging and refining is gone too: named structures are not
+ merged with other structures, even if their layout is identical. (of
+ course anonymous structures are still uniqued by layout).</li>
+
+ <li>TargetSelect.h moved to Support/ from Target/</li>
+
+ <li>UpgradeIntrinsicCall no longer upgrades pre-2.9 intrinsic calls (for
+ example <code>llvm.memset.i32</code>).</li>
+
+ <li>It is mandatory to initialize all out-of-tree passes too and their dependencies now with
+ <code>INITIALIZE_PASS{BEGIN,END,}</code>
+ and <code>INITIALIZE_{PASS,AG}_DEPENDENCY</code>.</li>
+
+ <li>The interface for MemDepResult in MemoryDependenceAnalysis has been
+ enhanced with new return types Unknown and NonFuncLocal, in addition to
+ the existing types Clobber, Def, and NonLocal.</li>
</ul>
+
+</div>
+
</div>
<!-- *********************************************************************** -->
-<h1>
+<h2>
<a name="knownproblems">Known Problems</a>
-</h1>
+</h2>
<!-- *********************************************************************** -->
-<div class="doc_text">
+<div>
-<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>
-
-</div>
+<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>
<!-- ======================================================================= -->
-<h2>
+<h3>
<a name="experimental">Experimental features included with this release</a>
-</h2>
+</h3>
-<div class="doc_text">
+<div>
<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>
+ 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, Blackfin, CellSPU, MicroBlaze, MSP430, MIPS, PTX, SystemZ
- and XCore backends are experimental.</li>
-<li><tt>llc</tt> "<tt>-filetype=obj</tt>" is experimental on all targets
- other than darwin and ELF X86 systems.</li>
-
+ <li>The Alpha, Blackfin, CellSPU, MicroBlaze, MSP430, MIPS, PTX, SystemZ and
+ XCore backends are experimental.</li>
+
+ <li><tt>llc</tt> "<tt>-filetype=obj</tt>" is experimental on all targets other
+ than darwin and ELF X86 systems.</li>
</ul>
</div>
<!-- ======================================================================= -->
-<h2>
+<h3>
<a name="x86-be">Known problems with the X86 back-end</a>
-</h2>
+</h3>
-<div class="doc_text">
+<div>
<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>
+ 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>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>
+ <tt>va_arg</tt>. Currently, front-ends support variadic argument
+ constructs on X86-64 by lowering them manually.</li>
+
<li>Windows x64 (aka Win64) code generator has a few issues.
<ul>
- <li>llvm-gcc cannot build the mingw-w64 runtime currently
- due to lack of support for the 'u' inline assembly
- constraint and for X87 floating point inline assembly.</li>
- <li>On mingw-w64, you will see unresolved symbol <tt>__chkstk</tt>
- due to <a href="http://llvm.org/bugs/show_bug.cgi?id=8919">Bug 8919</a>.
- It is fixed in <a href="http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20110321/118499.html">r128206</a>.</li>
+ <li>llvm-gcc cannot build the mingw-w64 runtime currently due to lack of
+ support for the 'u' inline assembly constraint and for X87 floating
+ point inline assembly.</li>
+
+ <li>On mingw-w64, you will see unresolved symbol <tt>__chkstk</tt> due
+ to <a href="http://llvm.org/bugs/show_bug.cgi?id=8919">Bug 8919</a>.
+ It is fixed
+ in <a href="http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20110321/118499.html">r128206</a>.</li>
+
<li>Miss-aligned MOVDQA might crash your program. It is due to
- <a href="http://llvm.org/bugs/show_bug.cgi?id=9483">Bug 9483</a>,
- lack of handling aligned internal globals.</li>
+ <a href="http://llvm.org/bugs/show_bug.cgi?id=9483">Bug 9483</a>, lack
+ of handling aligned internal globals.</li>
</ul>
</li>
</div>
<!-- ======================================================================= -->
-<h2>
+<h3>
<a name="ppc-be">Known problems with the PowerPC back-end</a>
-</h2>
+</h3>
-<div class="doc_text">
+<div>
<ul>
-<li>The Linux PPC32/ABI support needs testing for the interpreter and static
-compilation, and lacks support for debug information.</li>
+ <li>The Linux PPC32/ABI support needs testing for the interpreter and static
+ compilation, and lacks support for debug information.</li>
</ul>
</div>
<!-- ======================================================================= -->
-<h2>
+<h3>
<a name="arm-be">Known problems with the ARM back-end</a>
-</h2>
+</h3>
-<div class="doc_text">
+<div>
<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>
+ <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>
<!-- ======================================================================= -->
-<h2>
+<h3>
<a name="sparc-be">Known problems with the SPARC back-end</a>
-</h2>
+</h3>
-<div class="doc_text">
+<div>
<ul>
-<li>The SPARC backend only supports the 32-bit SPARC ABI (-m32); it does not
- support the 64-bit SPARC ABI (-m64).</li>
+ <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>
<!-- ======================================================================= -->
-<h2>
+<h3>
<a name="mips-be">Known problems with the MIPS back-end</a>
-</h2>
+</h3>
-<div class="doc_text">
+<div>
<ul>
-<li>64-bit MIPS targets are not supported yet.</li>
+ <li>64-bit MIPS targets are not supported yet.</li>
</ul>
</div>
<!-- ======================================================================= -->
-<h2>
+<h3>
<a name="alpha-be">Known problems with the Alpha back-end</a>
-</h2>
+</h3>
-<div class="doc_text">
+<div>
<ul>
-
-<li>On 21164s, some rare FP arithmetic sequences which may trap do not have the
-appropriate nops inserted to ensure restartability.</li>
-
+ <li>On 21164s, some rare FP arithmetic sequences which may trap do not have
+ the appropriate nops inserted to ensure restartability.</li>
</ul>
+
</div>
<!-- ======================================================================= -->
-<h2>
+<h3>
<a name="c-be">Known problems with the C back-end</a>
-</h2>
+</h3>
-<div class="doc_text">
+<div>
<p>The C backend has numerous problems and is not being actively maintained.
-Depending on it for anything serious is not advised.</p>
+ Depending on it for anything serious is not advised.</p>
<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>
+ <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>
<!-- ======================================================================= -->
-<h2>
+<h3>
<a name="llvm-gcc">Known problems with the llvm-gcc front-end</a>
-</h2>
+</h3>
-<div class="doc_text">
+<div>
-<p><b>LLVM 2.9 will be the last release of llvm-gcc.</b></p>
+<p><b>LLVM 2.9 was the last release of llvm-gcc.</b></p>
<p>llvm-gcc is generally very stable for the C family of languages. The only
major language feature of GCC not supported by llvm-gcc is the
<a href="#dragonegg">dragonegg</a> instead.</p>
<p>The llvm-gcc 4.2 Ada compiler has basic functionality, but is no longer being
-actively maintained. If you are interested in Ada, we recommend that you
-consider using <a href="#dragonegg">dragonegg</a> instead.</p>
+ actively maintained. If you are interested in Ada, we recommend that you
+ consider using <a href="#dragonegg">dragonegg</a> instead.</p>
+
+</div>
+
</div>
<!-- *********************************************************************** -->
-<h1>
+<h2>
<a name="additionalinfo">Additional Information</a>
-</h1>
+</h2>
<!-- *********************************************************************** -->
-<div class="doc_text">
+<div>
-<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>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>
+ us via the <a href="http://llvm.org/docs/#maillist"> mailing lists</a>.</p>
</div>
projects / oota-llvm.git / blobdiff