From 43ab46e2aa101ded49faa552e8e3f6fce8aecd1c Mon Sep 17 00:00:00 2001 From: Bill Wendling Date: Mon, 4 Oct 2010 19:55:17 +0000 Subject: [PATCH] Update release notes for 2.8 release. git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_28@115548 91177308-0d34-0410-b5e6-96231b3b80d8 --- docs/ReleaseNotes.html | 992 +++++++++++++++++++++++++++++------------ 1 file changed, 711 insertions(+), 281 deletions(-) diff --git a/docs/ReleaseNotes.html b/docs/ReleaseNotes.html index e6249a6d0b2..a8c20054c6b 100644 --- a/docs/ReleaseNotes.html +++ b/docs/ReleaseNotes.html @@ -3,6 +3,7 @@ + LLVM 2.8 Release Notes @@ -19,7 +20,6 @@
  • External Projects Using LLVM 2.8
  • What's New in LLVM 2.8?
  • Installation Instructions
    • -
  • Portability and Supported Platforms
  • Known Problems
  • Additional Information
    • @@ -28,11 +28,13 @@

    Written by the LLVM Team

    +
    @@ -66,23 +68,20 @@ current one. To see the release notes for a specific release, please see the Almost dead code. include/llvm/Analysis/LiveValues.h => Dan lib/Transforms/IPO/MergeFunctions.cpp => consider for 2.8. - llvm/Analysis/PointerTracking.h => Edwin wants this, consider for 2.8. GEPSplitterPass --> - - - + + +
    @@ -115,13 +114,32 @@ 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 and Objective-C on x86 (32- and 64-bit).

    +production-quality compiler for C, Objective-C, C++ and Objective-C++ on x86 +(32- and 64-bit), and for darwin-arm targets.

    In the LLVM 2.8 time-frame, the Clang team has made many improvements:

    -
      - -
    +
      +
    • Clang C++ is now feature-complete with respect to the ISO C++ 1998 and 2003 standards.
      • +
    • Added support for Objective-C++.
      • +
    • Clang now uses LLVM-MC to directly generate object code and to parse inline assembly (on Darwin).
      • +
    • Introduced many new warnings, including -Wmissing-field-initializers, -Wshadow, -Wno-protocol, -Wtautological-compare, -Wstrict-selector-match, -Wcast-align, -Wunused improvements, and greatly improved format-string checking.
      • +
    • Introduced the "libclang" library, a C interface to Clang intended to support IDE clients.
      • +
    • Added support for #pragma GCC visibility, #pragma align, and others.
      • +
    • Added support for SSE, ARM NEON, and Altivec.
      • +
    • Improved support for many Microsoft extensions.
      • +
    • Implemented support for blocks in C++.
      • +
    • Implemented precompiled headers for C++.
      • +
    • Improved abstract syntax trees to retain more accurate source information.
      • +
    • Added driver support for handling LLVM IR and bitcode files directly.
      • +
    • Major improvements to compiler correctness for exception handling.
      • +
    • Improved generated code quality in some areas: +
        +
      • Good code generation for X86-32 and X86-64 ABI handling.
        • +
      • Improved code generation for bit-fields, although important work remains.
        • +
      +
      • +
    @@ -138,11 +156,50 @@ production-quality compiler for C and Objective-C on x86 (32- and 64-bit).

    future!). The tool is very good at finding bugs that occur on specific paths through code, such as on error conditions.

    -

    In the LLVM 2.8 time-frame, +

    The LLVM 2.8 release fixes a number of bugs and slightly improves precision + over 2.7, but there are no major new features in the release.

    + +
    +DragonEgg: llvm-gcc ported to gcc-4.5 +
    + +
    +

    +DragonEgg is a port of llvm-gcc to +gcc-4.5. Unlike llvm-gcc, dragonegg in theory does not require any gcc-4.5 +modifications whatsoever (currently one small patch is needed) thanks to the +new gcc plugin architecture. +DragonEgg is a gcc plugin that makes gcc-4.5 use the LLVM optimizers and code +generators instead of gcc's, just like with llvm-gcc. +

    + +

    +DragonEgg is still a work in progress, but it is able to compile a lot of code, +for example all of gcc, LLVM and clang. Currently Ada, C, C++ and Fortran work +well, while all other languages either don't work at all or only work poorly. +For the moment only the x86-32 and x86-64 targets are supported, and only on +linux and darwin (darwin may need additional gcc patches). +

    + +

    +The 2.8 release has the following notable changes: +

    + +
    +
    VMKit: JVM/CLI Virtual Machine Implementation @@ -151,15 +208,13 @@ production-quality compiler for C and Objective-C on x86 (32- and 64-bit).

    The VMKit project is an implementation of -a JVM and a CLI Virtual Machine (Microsoft .NET is an -implementation of the CLI) using LLVM for static and just-in-time -compilation.

    - -

    With the release of LLVM 2.8, ...

    - +a Java Virtual Machine (Java VM or JVM) that uses LLVM for static and +just-in-time compilation. As of LLVM 2.8, VMKit now supports copying garbage +collectors, and can be configured to use MMTk's copy mark-sweep garbage +collector. In LLVM 2.8, the VMKit .NET VM is no longer being maintained. +

    -
    compiler-rt: Compiler Runtime Library @@ -178,67 +233,91 @@ libgcc routines).

    All of the code in the compiler-rt project is available under the standard LLVM -License, a "BSD-style" license. New in LLVM 2.8: +License, a "BSD-style" license. New in LLVM 2.8, compiler_rt now supports +soft floating point (for targets that don't have a real floating point unit), +and includes an extensive testsuite for the "blocks" language feature and the +blocks runtime included in compiler_rt.

    -Soft float support +
    + + +
    +LLDB: Low Level Debugger +
    + +
    +

    +LLDB 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.

    + +

    +LLDB is in early development and not included as part of the LLVM 2.8 release, +but is mature enough to support basic debugging scenarios on Mac OS X in C, +Objective-C and C++. We'd really like help extending and expanding LLDB to +support new platforms, new languages, new architectures, and new features.

    -DragonEgg: llvm-gcc ported to gcc-4.5 +libc++: C++ Standard Library

    -DragonEgg is a port of llvm-gcc to -gcc-4.5. Unlike llvm-gcc, which makes many intrusive changes to the underlying -gcc-4.2 code, dragonegg in theory does not require any gcc-4.5 modifications -whatsoever (currently one small patch is needed). This is thanks to the new -gcc plugin architecture, which -makes it possible to modify the behaviour of gcc at runtime by loading a plugin, -which is nothing more than a dynamic library which conforms to the gcc plugin -interface. DragonEgg is a gcc plugin that causes the LLVM optimizers to be run -instead of the gcc optimizers, and the LLVM code generators instead of the gcc -code generators, just like llvm-gcc. To use it, you add -"-fplugin=path/dragonegg.so" to the gcc-4.5 command line, and gcc-4.5 magically -becomes llvm-gcc-4.5! -

    +libc++ 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.

    -DragonEgg is still a work in progress. Currently C works very well, while C++, -Ada and Fortran work fairly well. All other languages either don't work at all, -or only work poorly. For the moment only the x86-32 and x86-64 targets are -supported, and only on linux and darwin (darwin needs an additional gcc patch). -

    - -

    -2.8 status here. +As of the LLVM 2.8 release, libc++ is virtually feature complete, but would +benefit from more testing and better integration with Clang++. It is also +looking forward to the C++ committee finalizing the C++'0x standard.

    +
    -llvm-mc: Machine Code Toolkit +KLEE: A Symbolic Execution Virtual Machine

    -The LLVM Machine Code (aka MC) sub-project of LLVM 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. It is a sub-project of LLVM which provides it with a number of advantages -over other compilers that do not have tightly integrated assembly-level tools. -For a gentle introduction, please see the Intro to the -LLVM MC Project Blog Post. +KLEE is a symbolic execution framework for +programs in LLVM bitcode form. KLEE tries to symbolically evaluate "all" paths +through the application and records state transitions that lead to fault +states. This allows it to construct testcases that lead to faults and can even +be used to verify some algorithms.

    -

    2.8 status here

    -
    +

    Although KLEE does not have any major new features as of 2.8, we have made +various minor improvements, particular to ease development:

    + + +
    @@ -254,6 +333,257 @@ LLVM MC Project Blog Post. projects that have already been updated to work with LLVM 2.8.

    + +
    +TTA-based Codesign Environment (TCE) +
    + +
    +

    +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.

    + +

    TCE uses llvm-gcc/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.

    + +
    + + +
    +Horizon Bytecode Compiler +
    + +
    +

    +Horizon is a bytecode +language and compiler written on top of LLVM, intended for producing +single-address-space managed code operating systems that +run faster than the equivalent multiple-address-space C systems. +More in-depth blurb is available on the wiki.

    + +
    + + +
    +Clam AntiVirus +
    + +
    +

    +Clam AntiVirus is an open source (GPL) +anti-virus toolkit for UNIX, designed especially for e-mail scanning on mail +gateways. Since version 0.96 it has bytecode +signatures that allow writing detections for complex malware. 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 2.8. +

    + +

    The +ClamAV bytecode compiler uses Clang and LLVM to compile a C-like +language, insert runtime checks, and generate ClamAV bytecode.

    + +
    + + +
    +Pure +
    + +
    +

    +Pure +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. 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 C interface. The interpreter uses +LLVM as a backend to JIT-compile Pure programs to fast native code.

    + +

    Pure versions 0.44 and later have been tested and are known to work with +LLVM 2.8 (and continue to work with older LLVM releases >= 2.5).

    + +
    + + +
    +Glasgow Haskell Compiler (GHC) +
    + +
    +

    +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.

    + +

    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.

    + +
    + + +
    +Clay Programming Language +
    + +
    +

    +Clay is a new systems programming +language that is specifically designed for generic programming. It makes +generic programming very concise thanks to whole program type propagation. It +uses LLVM as its backend.

    + +
    + + +
    +llvm-py Python Bindings for LLVM +
    + +
    +

    +llvm-py has been updated to work +with LLVM 2.8. llvm-py provides Python bindings for LLVM, allowing you to write a +compiler backend or a VM in Python.

    + +
    + + + +
    +FAUST Real-Time Audio Signal Processing Language +
    + +
    +

    +FAUST 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 and +2.8.

    + +
    + + +
    +Jade Just-in-time Adaptive Decoder Engine +
    + +
    +

    Jade +(Just-in-time Adaptive Decoder Engine) is a generic video decoder engine using +LLVM for just-in-time compilation of video decoder configurations. Those +configurations are designed by MPEG Reconfigurable Video Coding (RVC) committee. +MPEG RVC standard is built on a stream-based dataflow representation of +decoders. It is composed of a standard library of coding tools written in +RVC-CAL language and a dataflow configuration — block diagram — +of a decoder.

    + +

    Jade project is hosted as part of the Open +RVC-CAL Compiler and requires it to translate the RVC-CAL standard library +of video coding tools into an LLVM assembly code.

    + +
    + + +
    +LLVM JIT for Neko VM +
    + +
    +

    Neko LLVM JIT +replaces the standard Neko JIT with an LLVM-based implementation. While not +fully complete, it is already providing a 1.5x speedup on 64-bit systems. +Neko LLVM JIT requires LLVM 2.8 or later.

    + +
    + + +
    +Crack Scripting Language +
    + +
    +

    +Crack 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. Crack 0.2 works with LLVM 2.7, and the forthcoming Crack 0.2.1 release +builds on LLVM 2.8.

    + +
    + + +
    +Dresden TM Compiler (DTMC) +
    + +
    +

    +DTMC provides support for +Transactional Memory, which is an easy-to-use and efficient way to synchronize +accesses to shared memory. Transactions can contain normal C/C++ code (e.g., +__transaction { list.remove(x); x.refCount--; }) and will be executed +virtually atomically and isolated from other transactions.

    + +
    + + +
    +Kai Programming Language +
    + +
    +

    +Kai (Japanese 会 for +meeting/gathering) is an experimental interpreter that provides a highly +extensible runtime environment and explicit control over the compilation +process. Programs are defined using nested symbolic expressions, which are all +parsed into first-class values with minimal intrinsic semantics. Kai can +generate optimised code at run-time (using LLVM) in order to exploit the nature +of the underlying hardware and to integrate with external software libraries. +It is a unique exploration into world of dynamic code compilation, and the +interaction between high level and low level semantics.

    + +
    + + +
    +OSL: Open Shading Language +
    + +
    +

    +OSL is a shading +language designed for use in physically based renderers and in particular +production rendering. By using LLVM instead of the interpreter, it was able to +meet its performance goals (>= C-code) while retaining the benefits of +runtime specialization and a portable high-level language. +

    + +
    + +
    @@ -270,21 +600,6 @@ in this section.
    - -
    -LLVM Community Changes -
    - -
    - -

    In addition to changes to the code, between LLVM 2.7 and 2.8, a number of -organization changes have happened: -

    - - -
    -
    Major New Features @@ -295,7 +610,16 @@ organization changes have happened:

    LLVM 2.8 includes several major new capabilities:

    @@ -310,61 +634,19 @@ organization changes have happened: expose new optimization opportunities:

    @@ -380,27 +662,82 @@ want your pass to work with both LLVM 2.7 and 2.8 release includes a few major enhancements and additions to the optimizers:

    - + +
    -Interpreter and JIT Improvements +MC Level Improvements
    +

    +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.

    + +

    The MC subproject has made great leaps in LLVM 2.8. For example, support for + directly writing .o files from LLC (and clang) now works reliably for + darwin/x86[-64] (including inline assembly support) and the integrated + assembler is turned on by default in Clang for these targets. This provides + improved compile times among other things.

    -
    +

    For more information, please see the Intro to the +LLVM MC Project Blog Post. +

    + + +
    @@ -414,7 +751,58 @@ infrastructure, which allows us to implement more aggressive algorithms and make it run faster:

    @@ -424,14 +812,46 @@ it run faster:

    -

    New features of the X86 target include: +

    New features and major changes in the X86 target include:

    @@ -446,44 +866,72 @@ it run faster:

    - - - - - -
    -New Useful APIs -
    - -
    - -

    This release includes a number of new APIs that are used internally, which - may also be useful for external clients. -

    - - - - -
    - - -
    -Other Improvements and New Features -
    - -
    -

    Other miscellaneous features include:

    - - -
    @@ -499,53 +947,85 @@ on LLVM 2.7, this section lists some "gotchas" that you may run into upgrading from the previous release.

    + +

    In addition, many APIs have changed in this release. Some of the major LLVM API changes are:

    - - - -
    - Portability and Supported Platforms -
    - - -
    - -

    LLVM is known to work on the following platforms:

    - - - -

    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.

    - -
    -
    Known Problems @@ -559,18 +1039,6 @@ listed by component. If you run into a problem, please check the LLVM bug database and submit a bug if there isn't already one.

    - -
    @@ -588,10 +1056,10 @@ components, please contact us on the LLVMdev list.

    @@ -699,6 +1167,9 @@ appropriate nops inserted to ensure restartability.
    +

    The C backend has numerous problems and is not being actively maintained. +Depending on it for anything serious is not advised.

    +