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author | Bill Wendling <isanbard@gmail.com> | 2012-05-15 21:58:06 +0000 |
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committer | Bill Wendling <isanbard@gmail.com> | 2012-05-15 21:58:06 +0000 |
commit | 1f3405800a99939005fd5d27b712e08ecceb5975 (patch) | |
tree | 6ba45af07957076c6c537a492064f67a4d2206cb | |
parent | c72b7c689a430975c46ae49a7a46d3224979d526 (diff) |
Update.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_31@156862 91177308-0d34-0410-b5e6-96231b3b80d8
-rw-r--r-- | docs/ReleaseNotes.html | 368 |
1 files changed, 269 insertions, 99 deletions
diff --git a/docs/ReleaseNotes.html b/docs/ReleaseNotes.html index 482cc48698..170758b89b 100644 --- a/docs/ReleaseNotes.html +++ b/docs/ReleaseNotes.html @@ -29,12 +29,6 @@ <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 3.1 -release.<br> -You may prefer the -<a href="http://llvm.org/releases/3.0/docs/ReleaseNotes.html">LLVM 3.0 -Release Notes</a>.</h1> - <!-- *********************************************************************** --> <h2> <a name="intro">Introduction</a> @@ -74,9 +68,9 @@ Release Notes</a>.</h1> <p>The LLVM 3.1 distribution currently consists of code from the core LLVM repository (which roughly includes the LLVM optimizers, code generators and - supporting tools), and the Clang 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> + supporting tools), and the Clang 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> <!--=========================================================================--> <h3> @@ -94,7 +88,8 @@ Release Notes</a>.</h1> 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 3.1 time-frame, the Clang team has made many improvements:</p> +<p>In the LLVM 3.1 time-frame, the Clang team has made many improvements. + Highlights include:</p> <ul> <li>Greatly expanded <a href="http://clang.llvm.org/cxx_status.html">C++11 support</a> including lambdas, initializer lists, constexpr, user-defined @@ -106,10 +101,9 @@ Release Notes</a>.</h1> Objective C</a>.</li> </ul> - <p>For more details about the changes to Clang since the 3.0 release, see the -<a href="http://clang.llvm.org/docs/ReleaseNotes.html">Clang release notes</a> -</p> - +<p>For more details about the changes to Clang since the 3.0 release, see the + <a href="http://clang.llvm.org/docs/ReleaseNotes.html">Clang release + notes.</a></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 @@ -124,6 +118,7 @@ Release Notes</a>.</h1> </h3> <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. It works with gcc-4.5 and gcc-4.6 @@ -134,8 +129,7 @@ Release Notes</a>.</h1> <p>The 3.1 release has the following notable changes:</p> - <ul> - +<ul> <li>Partial support for gcc-4.7. Ada support is poor, but other languages work fairly well.</li> @@ -150,7 +144,6 @@ Release Notes</a>.</h1> aliasing and type ranges to the LLVM optimizers.</li> <li>A regression test-suite was added.</li> - </ul> </div> @@ -171,7 +164,9 @@ Release Notes</a>.</h1> implementations of this and other low-level routines (some are 3x faster than the equivalent libgcc routines).</p> -<p>....</p> +<p>As of 3.1, compiler-rt includes the helper functions for atomic operations, + allowing atomic operations on arbitrary-sized quantities to work. These + functions follow the specification defined by gcc and are used by clang.</p> </div> @@ -182,12 +177,11 @@ Release Notes</a>.</h1> <div> -<p>LLDB is a ground-up implementation of a command line debugger, as well as a - debugger API that can be used from other applications. LLDB makes use of the - Clang parser to provide high-fidelity expression parsing (particularly for - C++) and uses the LLVM JIT for target support.</p> - -<p>...</p> +<p><a href="http://lldb.llvm.org">LLDB</a> is a ground-up implementation of a + command line debugger, as well as a debugger API that can be used from other + applications. LLDB makes use of the Clang parser to provide high-fidelity + expression parsing (particularly for C++) and uses the LLVM JIT for target + support.</p> </div> @@ -202,7 +196,16 @@ Release Notes</a>.</h1> licensed</a> under the MIT and UIUC license, allowing it to be used more permissively.</p> -<p>...</p> +<p>Within the LLVM 3.1 time-frame there were the following highlights:</p> + +<ul> + <li>The <code><atomic></code> header is now passing all tests, when + compiling with clang and linking against the support code from + compiler-rt.</li> + <li>FreeBSD now includes libc++ as part of the base system.</li> + <li>libc++ has been ported to Solaris and, in combination with libcxxrt and + clang, is working with a large body of existing code.</li> +</ul> </div> @@ -213,16 +216,12 @@ Release Notes</a>.</h1> <div> - <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. +<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.</p> - <p>In the LLVM 3.1 time-frame, VMKit has had significant improvements on both - runtime and startup performance:</p> - - <ul> - <li>...</li> - </ul> +<p>In the LLVM 3.1 time-frame, VMKit has had significant improvements on both + runtime and startup performance.</p> </div> @@ -234,25 +233,23 @@ Release Notes</a>.</h1> <div> - <p><a href="http://polly.llvm.org/">Polly</a> is an <em>experimental</em> +<p><a href="http://polly.llvm.org/">Polly</a> is an <em>experimental</em> optimizer for data locality and parallelism. It currently provides high-level loop optimizations and automatic parallelisation (using the OpenMP run time). Work in the area of automatic SIMD and accelerator code generation was - started. + started.</p> - <p>Within the LLVM 3.1 time-frame there were the following highlights:</p> +<p>Within the LLVM 3.1 time-frame there were the following highlights:</p> - <ul> +<ul> <li>Polly became an official LLVM project</li> - <li>Polly can be loaded directly into clang (Enabled by '-O3 -mllvm -polly' - )</li> - <li>An automatic scheduling optimizer (derived from <a - href="http://pluto-compiler.sourceforge.net/">Pluto</a>) was integrated. It - performs loop transformations to optimize for data-locality and parallelism. - The transformations include, but are not limited to interchange, fusion, - fission, skewing and tiling. - </li> - </ul> + <li>Polly can be loaded directly into clang (enabled by '-O3 -mllvm -polly')</li> + <li>An automatic scheduling optimizer (derived + from <a href="http://pluto-compiler.sourceforge.net/">Pluto</a>) was + integrated. It performs loop transformations to optimize for data-locality + and parallelism. The transformations include, but are not limited to + interchange, fusion, fission, skewing and tiling.</li> +</ul> </div> @@ -270,21 +267,143 @@ Release Notes</a>.</h1> a lot of other language and tools projects. This section lists some of the projects that have already been updated to work with LLVM 3.1.</p> +<h3>Crack</h3> + +<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>FAUST</h3> + +<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, + JavaScript output formats, the Faust compiler can generate LLVM bitcode, and + works with LLVM 2.7-3.1.</p> + +</div> + +<h3>Glasgow Haskell Compiler (GHC)</h3> + +<div> + +<p><a href="http://www.haskell.org/ghc/">GHC</a> is an open source compiler and + programming suite for Haskell, a 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.</p> + +</div> + +<h3>Julia</h3> + +<div> + +<p><a href="https://github.com/JuliaLang/julia">Julia</a> is a high-level, + high-performance dynamic language for technical computing. It provides a + sophisticated compiler, distributed parallel execution, numerical accuracy, + and an extensive mathematical function library. The compiler uses type + inference to generate fast code without any type declarations, and uses + LLVM's optimization passes and JIT compiler. The + <a href="http://julialang.org/"> Julia Language</a> is designed + around multiple dispatch, giving programs a large degree of flexibility. It + is ready for use on many kinds of problems.</p> + +</div> + +<h3>LLVM D Compiler</h3> + +<div> + +<p><a href="https://github.com/ldc-developers/ldc">LLVM D Compiler</a> (LDC) is + a compiler for the D programming Language. It is based on the DMD frontend + and uses LLVM as backend.</p> + +</div> + +<h3>Open Shading Language</h3> + +<div> + +<p><a href="https://github.com/imageworks/OpenShadingLanguage/">Open Shading + Language (OSL)</a> is a small but rich language for programmable shading in + advanced global illumination renderers and other applications, ideal for + describing materials, lights, displacement, and pattern generation. It uses + LLVM to JIT complex shader networks to x86 code at runtime.</p> + +<p>OSL was developed by Sony Pictures Imageworks for use in its in-house + renderer used for feature film animation and visual effects, and is + distributed as open source software with the "New BSD" license.</p> + +</div> + +<h3>Portable OpenCL (pocl)</h3> + +<div> + +<p>In addition to producing an easily portable open source OpenCL + implementation, another major goal of <a href="http://pocl.sourceforge.net/"> + pocl</a> is improving performance portability of OpenCL programs with + compiler optimizations, reducing the need for target-dependent manual + optimizations. An important part of pocl is a set of LLVM passes used to + statically parallelize multiple work-items with the kernel compiler, even in + the presence of work-group barriers. This enables static parallelization of + the fine-grained static concurrency in the work groups in multiple ways + (SIMD, VLIW, superscalar,...).</p> + +</div> + <h3>Pure</h3> -<p>Pure (http://pure-lang.googlecode.com/) 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> +<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 0.54 has been tested and is known to work with LLVM 3.1 (and -continues to work with older LLVM releases >= 2.5).</p> + continues to work with older LLVM releases >= 2.5).</p> + +</div> + +<h3>TTA-based Co-design Environment (TCE)</h3> + +<div> + +<p><a href="http://tce.cs.tut.fi/">TCE</a> 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/Verilog 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> + +</div> </div> @@ -335,7 +454,6 @@ continues to work with older LLVM releases >= 2.5).</p> A full featured assembler and direct-to-object support for ARM.</li> <li><a href="#blockplacement">Basic Block Placement</a> Probability driven basic block placement.</li> - <li>....</li> </ul> </div> @@ -351,18 +469,22 @@ continues to work with older LLVM releases >= 2.5).</p> <p>LLVM IR has several new features for better support of new targets and that expose new optimization opportunities:</p> - <ul> - <li>IR support for half float</li> - <li>IR support for vectors of pointers, including vector GEPs.</li> - <li>Module flags have been introduced. They convey information about the - module as a whole to LLVM subsystems.</li> - <li>Loads can now have range metadata attached to them to describe the - possible values being loaded.</li> - <li>Inline cost heuristics have been completely overhauled and now closely - model constant propagation through call sites, disregard trivially dead - code costs, and can model C++ STL iterator patterns.</li> - <li>....</li> - </ul> +<ul> + <li>A new type representing 16 bit <i>half</i> floating point values has + been added.</li> + <li>IR now supports vectors of pointers, including vector GEPs.</li> + <li>Module flags have been introduced. They convey information about the + module as a whole to LLVM subsystems. This is currently used to encode + Objective C ABI information.</li> + <li>Loads can now have range metadata attached to them to describe the + possible values being loaded.</li> + <li>The <tt>llvm.ctlz</tt> and <tt>llvm.cttz</tt> intrinsics now have an + additional argument which indicates whether the behavior of the intrinsic + is undefined on a zero input. This can be used to generate more efficient + code on platforms that only have instructions which don't return the type + size when counting bits in 0.</li> +</ul> + </div> <!--=========================================================================--> @@ -385,7 +507,9 @@ continues to work with older LLVM releases >= 2.5).</p> post-vectorization cleanup passes. For more information, see the EuroLLVM 2012 slides: <a href="http://llvm.org/devmtg/2012-04-12/Slides/Hal_Finkel.pdf"> Autovectorization with LLVM</a>.</li> - <li>....</li> + <li>Inline cost heuristics have been completely overhauled and now closely + model constant propagation through call sites, disregard trivially dead + code costs, and can model C++ STL iterator patterns.</li> </ul> </div> @@ -405,7 +529,9 @@ continues to work with older LLVM releases >= 2.5).</p> to the LLVM MC Project Blog Post</a>.</p> <ul> - <li>....</li> + <li>The integrated assembler can optionally emit debug information when + assembling a </tt>.s</tt> file. It can be enabled by passing the + <tt>-g</tt> option to <tt>llvm-mc</tt>.</li> </ul> </div> @@ -442,6 +568,9 @@ continues to work with older LLVM releases >= 2.5).</p> representation of large clobber lists on call instructions. The register mask operand references a bit mask of preserved registers. Everything else is clobbered.</li> + <li>The DWARF debug info writer gained support for emitting data for the + <a href="SourceLevelDebugging.html#acceltable">name accelerator tables + DWARF extension</a>. It is used by LLDB to speed up name lookup.</li> </ul> <p> We added new TableGen infrastructure to support bundling for @@ -475,13 +604,14 @@ static heuristics as well as source code annotations such as <p>New features and major changes in the X86 target include:</p> <ul> - <li>Bug fixes and improved support for AVX1</li> - <li>Support for AVX2 (still incomplete at this point)</li> + <li>Greatly improved support for AVX2.</li> + <li>Lots of bug fixes and improvements for AVX1.</li> + <li>Support for the FMA4 and XOP instruction set extensions.</li> <li>Call instructions use the new register mask operands for faster compile times and better support for different calling conventions. The old WINCALL instructions are no longer needed.</li> <li>DW2 Exception Handling is enabled on Cygwin and MinGW.</li> - <li>Support for implicit TLS model used with MS VC runtime</li> + <li>Support for implicit TLS model used with MSVC runtime.</li> </ul> </div> @@ -526,28 +656,47 @@ syntax, there are still significant gaps in that support.</p> </h3> <div> - -<p>This release has seen major new work on just about every aspect of the MIPS - backend. Some of the major new features include:</p> +New features and major changes in the MIPS target include:</p> <ul> - <li>....</li> + <li>MIPS32 little-endian direct object code emission is functional.</li> + <li>MIPS64 little-endian code generation is largely functional for N64 ABI in assembly printing mode with the exception of handling of long double (f128) type.</li> + <li>Support for new instructions has been added, which includes swap-bytes + instructions (WSBH and DSBH), floating point multiply-add/subtract and + negative multiply-add/subtract instructions, and floating + point load/store instructions with reg+reg addressing (LWXC1, etc.)</li> + <li>Various fixes to improve performance have been implemented.</li> + <li>Post-RA scheduling is now enabled at -O3.</li> + <li>Support for soft-float code generation has been added.</li> + <li>clang driver's support for MIPS 64-bits targets.</li> + <li>Support for MIPS floating point ABI option in clang driver.</li> </ul> </div> <!--=========================================================================--> <h3> -<a name="OtherTS">Other Target Specific Improvements</a> +<a name="PTX">PTX Target Improvements</a> </h3> <div> -<p>Support for Qualcomm's Hexagon VLIW processor has been added.</p> +<p>An outstanding conditional inversion bug was fixed in this release.</p> -<ul> - <li>....</li> +<p><b>NOTE</b>: LLVM 3.1 marks the last release of the PTX back-end, in its + current form. The back-end is currently being replaced by the NVPTX + back-end, currently in SVN ToT.</p> + +</div> + +<!--=========================================================================--> +<h3> +<a name="OtherTS">Other Target Specific Improvements</a> +</h3> +<div> +<ul> + <li>Support for Qualcomm's Hexagon VLIW processor has been added.</li> </ul> </div> @@ -564,6 +713,12 @@ syntax, there are still significant gaps in that support.</p> from the previous release.</p> <ul> + <li>LLVM's build system now requires a python 2 interpreter to be present at + build time. A perl interpreter is no longer required.</li> + <li>The C backend has been removed. It had numerous problems, to the point of + not being able to compile any nontrivial program.</li> + <li>The Alpha, Blackfin and SystemZ targets have been removed due to lack of + maintenance.</li> <li>LLVM 3.1 removes support for reading LLVM 2.9 bitcode files. Going forward, we aim for all future versions of LLVM to read bitcode files and <tt>.ll</tt> files produced by LLVM 3.0 and later.</li> @@ -573,7 +728,6 @@ syntax, there are still significant gaps in that support.</p> <li>LLVM 3.0 and earlier automatically added the returns_twice fo functions like setjmp based on the name. This functionality was removed in 3.1. This affects Clang users, if -ffreestanding is used.</li> - <li>....</li> </ul> </div> @@ -620,9 +774,9 @@ syntax, there are still significant gaps in that support.</p> <li><code>llvm::getTrapFunctionName()</code></li> <li><code>llvm::EnableSegmentedStacks</code></li> </ul></li> - <li>The MDBuilder class has been added to simplify the creation of - metadata.</li> - <li>....</li> + + <li>The <code>MDBuilder</code> class has been added to simplify the creation + of metadata.</li> </ul> </div> @@ -639,16 +793,37 @@ syntax, there are still significant gaps in that support.</p> <ul> - <li>llvm-stress is a command line tool for generating random .ll files to fuzz - different LLVM components. </li> - <li>llvm-ld has been removed. Use llvm-link or Clang instead.</li> - <li>....</li> + <li><tt>llvm-stress</tt> is a command line tool for generating random + <tt>.ll</tt> files to fuzz different LLVM components. </li> + <li>The <tt>llvm-ld</tt> tool has been removed. The clang driver provides a + more reliable solution for turning a set of bitcode files into a binary. + To merge bitcode files <tt>llvm-link</tt> can be used instead.</li> </ul> +</div> + + +<!--=========================================================================--> +<h3> +<a name="python">Python Bindings</a> +</h3> + +<div> + +<p>Officially supported Python bindings have been added! Feature support is far +from complete. The current bindings support interfaces to:</p> <ul> - <li>....</li> + <li>Object File Interface</li> + <li>Disassembler</li> </ul> +<p>Using the Object File Interface, it is possible to inspect binary object files. +Think of it as a Python version of readelf or llvm-objdump.</p> + +<p>Support for additional features is currently being developed by community +contributors. If you are interested in shaping the direction of the Python +bindings, please express your intent on IRC or the developers list.</p> + </div> </div> @@ -673,18 +848,13 @@ syntax, there are still significant gaps in that support.</p> <p>Known problem areas include:</p> <ul> - <li>The Alpha, Blackfin, CellSPU, MSP430, PTX, SystemZ and - XCore backends are experimental, and the Alpha, Blackfin and SystemZ - targets have already been removed from mainline.</li> + <li>The CellSPU, MSP430, PTX and XCore backends are experimental.</li> <li>The integrated assembler, disassembler, and JIT is not supported by several targets. If an integrated assembler is not supported, then a system assembler is required. For more details, see the <a href="CodeGenerator.html#targetfeatures">Target Features Matrix</a>. </li> - - <li>The C backend has numerous problems and is not being actively maintained. - Depending on it for anything serious is not advised.</li> </ul> </div> |