+ width="136" height="136" alt="LLVM Dragon Logo">
Written by the LLVM Team
-This document contains the release notes for the LLVM Compiler -Infrastructure, release 2.7. Here we describe the status of LLVM, including +Infrastructure, release 2.8. 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 LLVM releases web site.
@@ -51,8 +51,8 @@ href="http://llvm.org/releases/">LLVM releases web site.For more information about LLVM, including information about the latest release, please check out the main LLVM web site. If you have questions or comments, the LLVM Developer's Mailing -List is a good place to send them.
+href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM Developer's +Mailing List is a good place to send them.Note that if you are reading this file from a Subversion checkout or the main LLVM web page, this document applies to the next release, not the @@ -67,32 +67,22 @@ 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. - ABCD, SCCVN, GEPSplitterPass + ABCD, GEPSplitterPass MSIL backend? + lib/Transforms/Utils/SSI.cpp -> ABCD depends on it. --> - @@ -103,7 +93,7 @@ Almost dead code.
-The LLVM 2.7 distribution currently consists of code from the core LLVM +The LLVM 2.8 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 @@ -120,12 +110,49 @@ development. Here we include updates on these subprojects.
The Clang project is ...
+Clang 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 and Objective-C on x86 (32- and 64-bit).
In the LLVM 2.7 time-frame, the Clang team has made many improvements:
void function, etc.), sign-comparison warnings, and improved
+format-string warnings.Previously announced in the 2.4, 2.5, and 2.6 LLVM releases, the Clang project also -includes an early stage static source code analysis tool for automatically finding bugs -in C and Objective-C programs. The tool performs checks to find -bugs that occur on a specific path within a program.
- -In the LLVM 2.7 time-frame, the analyzer core has sprouted legs and...
+The Clang Static Analyzer + project is an effort to use static source code analysis techniques to + automatically find bugs in C and Objective-C programs (and hopefully C++ in the + future!). The tool is very good at finding bugs that occur on specific + paths through code, such as on error conditions.
+ +In the LLVM 2.7 time-frame, the analyzer core has made several major and + minor improvements, including better support for tracking the fields of + structures, initial support (not enabled by default yet) for doing + interprocedural (cross-function) analysis, and new checks have been added. +
-VMKit version ?? builds with LLVM 2.7 and you can find it on its -web page. The release includes -bug fixes, cleanup and new features. The major changes are:
+With the release of LLVM 2.7, VMKit has shifted to a great framework for writing +virtual machines. VMKit now offers precise and efficient garbage collection with +multi-threading support, thanks to the MMTk memory management toolkit, as well +as just in time and ahead of time compilation with LLVM. The major changes in +VMKit 0.27 are:All of the code in the compiler-rt project is available under the standard LLVM -License, a "BSD-style" license.
+License, a "BSD-style" license. New in LLVM 2.7: compiler_rt now +supports ARM targets.-The new LLVM KLEE project 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 algorithms. For more -details, please see the OSDI 2008 paper about -KLEE.
- -+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). +
--The goal of DragonEgg is to make -gcc-4.5 act like llvm-gcc without requiring any gcc modifications whatsoever. -DragonEgg is a shared library (dragonegg.so) -that is loaded by gcc at runtime. It ... +DragonEgg is a new project which is seeing its first release with llvm-2.7.
-The LLVM Machine Code (MC) Toolkit project is ... +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.
+2.7 includes major parts of the work required by the new MC Project. A few + targets have been refactored to support it, and work is underway to support a + native assembler in LLVM. This work is not complete in LLVM 2.7, but it has + made substantially more progress on LLVM mainline.
+ +One minor example of what MC can do is to transcode an AT&T syntax + X86 .s file into intel syntax. You can do this with something like:
++ llvm-mc foo.s -output-asm-variant=1 -o foo-intel.s ++
-Need update. -
- --Need update. -
-Pure versions 0.43 and later have been tested and are known to work with +LLVM 2.7 (and continue to work with older LLVM releases >= 2.5).
- - - --Need update. - -
-Need update. -
+-Need update. - +compiler.
-Need update. - +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.
+ ++SAFECode is a memory safe C +compiler built using LLVM. It takes standard, unannotated 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.
-Need update. - +code.
+Icedtea6 1.8 and later have been tested and are known to work with +LLVM 2.7 (and continue to work with older LLVM releases >= 2.6 as well). +
++LLVM-Lua uses LLVM + to add JIT and static compiling support to the Lua VM. Lua +bytecode is analyzed to remove type checks, then LLVM is used to compile the +bytecode down to machine code. +
+LLVM-Lua 1.2.0 have been tested and is known to work with LLVM 2.7. +
++MacRuby is an implementation of Ruby based on +core Mac OS technologies, sponsored by Apple Inc. It uses LLVM at runtime for +optimization passes, JIT compilation and exception handling. It also allows +static (ahead-of-time) compilation of Ruby code straight to machine code. +
+The upcoming MacRuby 0.6 release works with LLVM 2.7. +
++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 now +supports an LLVM +code generator. GHC supports LLVM 2.7.
+ +In addition to changes to the code, between LLVM 2.6 and 2.7, a number of +organization changes have happened: +
+ +LLVM 2.7 includes several major new capabilities:
Also, -anders-aa was removed
- @@ -487,15 +676,20 @@ release includes a few major enhancements and additions to the optimizers:New features of the PIC16 target include: -
- -Things not yet supported:
- -New features of other targets include: -
+Other miscellaneous features include:
In addition, many APIs have changed in this release. Some of the major LLVM API changes are:
If you run into GCC extensions which are not supported, please let us know. -
- -The C++ front-end is considered to be fully -tested and works for a number of non-trivial programs, including LLVM -itself, Qt, Mozilla, etc.
- -The Llvm.Linkage module is broken, and has incorrect values. Only -Llvm.Linkage.External, Llvm.Linkage.Available_externally, and -Llvm.Linkage.Link_once will be correct. If you need any of the other linkage -modes, you'll have to write an external C library in order to expose the -functionality. This has been fixed in the trunk.
-