<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
- <link rel="stylesheet" href="llvm.css" type="text/css">
- <title>LLVM 3.1 Release Notes</title>
+ <link rel="stylesheet" href="_static/llvm.css" type="text/css">
+ <title>LLVM 3.2 Release Notes</title>
</head>
<body>
-<h1>LLVM 3.1 Release Notes</h1>
+<h1>LLVM 3.2 Release Notes</h1>
<div>
<img style="float:right" src="http://llvm.org/img/DragonSmall.png"
<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 3.1</a></li>
+ <li><a href="#externalproj">External Projects Using LLVM 3.2</a></li>
<li><a href="#whatsnew">What's New in LLVM?</a></li>
<li><a href="GettingStarted.html">Installation Instructions</a></li>
<li><a href="#knownproblems">Known Problems</a></li>
<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
+<h1 style="color:red">These are in-progress notes for the upcoming LLVM 3.2
release.<br>
You may prefer the
-<a href="http://llvm.org/releases/3.0/docs/ReleaseNotes.html">LLVM 3.0
+<a href="http://llvm.org/releases/3.1/docs/ReleaseNotes.html">LLVM 3.1
Release Notes</a>.</h1>
<!-- *********************************************************************** -->
<div>
<p>This document contains the release notes for the LLVM Compiler
- Infrastructure, release 3.1. Here we describe the status of LLVM, including
+ Infrastructure, release 3.2. Here we describe the status of LLVM, including
major improvements from the previous release, improvements in various
- subprojects of LLVM, and some of the current users of the code.
- All LLVM releases may be downloaded from
- the <a href="http://llvm.org/releases/">LLVM releases web site</a>.</p>
+ subprojects of LLVM, and some of the current users of the code. 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
<div>
-<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>
+<p>The LLVM 3.2 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>
<!--=========================================================================-->
<h3>
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 3.2 time-frame, the Clang team has made many improvements.
+ Highlights include:</p>
<ul>
<li>...</li>
</ul>
- <p>For more details about the changes to Clang since the 2.9 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 3.1 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
</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 or gcc-4.6,
- targets the x86-32 and x86-64 processor families, and has been successfully
- used on the Darwin, FreeBSD, KFreeBSD, Linux and OpenBSD platforms. It fully
- supports Ada, C, C++ and Fortran. It has partial support for Go, Java, Obj-C
- and Obj-C++.</p>
+ optimizers and code generators with LLVM's. It works with gcc-4.5 and gcc-4.6
+ (and partially with gcc-4.7), can target the x86-32/x86-64 and ARM processor
+ families, and has been successfully used on the Darwin, FreeBSD, KFreeBSD,
+ Linux and OpenBSD platforms. It fully supports Ada, C, C++ and Fortran. It
+ has partial support for Go, Java, Obj-C and Obj-C++.</p>
-<p>The 3.1 release has the following notable changes:</p>
-
- <ul>
+<p>The 3.2 release has the following notable changes:</p>
+<ul>
<li>...</li>
-
</ul>
</div>
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>
+ <code>__fixunsdfdi</code> 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>The 3.2 release has the following notable changes:</p>
-<p>....</p>
+<ul>
+ <li>...</li>
+</ul>
</div>
<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><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>
-<p>...</p>
+<p>The 3.2 release has the following notable changes:</p>
+
+<ul>
+ <li>...</li>
+</ul>
</div>
licensed</a> under the MIT and UIUC license, allowing it to be used more
permissively.</p>
-<p>...</p>
+<p>Within the LLVM 3.2 time-frame there were the following highlights:</p>
+
+<ul>
+ <li>...</li>
+</ul>
</div>
<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>
+<p>The 3.2 release has the following notable changes:</p>
- <ul>
+<ul>
<li>...</li>
- </ul>
+</ul>
+
+</div>
+
+
+<!--=========================================================================-->
+<h3>
+<a name="Polly">Polly: Polyhedral Optimizer</a>
+</h3>
+
+<div>
+
+<p><a href="http://polly.llvm.org/">Polly</a> is an <em>experimental</em>
+ optimizer for data locality and parallelism. It provides high-level
+ loop optimizations and automatic parallelisation.</p>
+
+<p>Within the LLVM 3.2 time-frame there were the following highlights:</p>
+
+<ul>
+ <li>isl, the integer set library used by Polly, was relicensed to the MIT
+license</li>
+ <li>isl based code generation<br />
+ <ul>
+<li>MIT licensed replacement for CLooG (LGPLv2) </li>
+<li>Fine grained option handling (separation of
+core and border computations, control overhead vs. code size) </li>
+</li>
+</ul>
+<li>Support for FORTRAN and dragonegg</li>
+<li>OpenMP code generation fixes</li>
+</ul>
+
</div>
<!-- *********************************************************************** -->
<h2>
- <a name="externalproj">External Open Source Projects Using LLVM 3.1</a>
+ <a name="externalproj">External Open Source Projects Using LLVM 3.2</a>
</h2>
<!-- *********************************************************************** -->
<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 3.1.</p>
+ a lot of other language and tools projects. This section lists some of the
+ projects that have already been updated to work with LLVM 3.2.</p>
+
+<h3>Crack</h3>
+
+<div>
- ... to be filled in right before the release ...
+<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>
+
+<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>
+
+</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>
<!-- *********************************************************************** -->
<h2>
- <a name="whatsnew">What's New in LLVM 3.1?</a>
+ <a name="whatsnew">What's New in LLVM 3.2?</a>
</h2>
<!-- *********************************************************************** -->
<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
+ minor improvements. Some of the major improvements and new features are
listed in this section.</p>
<!--=========================================================================-->
<div>
- <!-- Features that need text if they're finished for 3.1:
+ <!-- Features that need text if they're finished for 3.2:
ARM EHABI
combiner-aa?
strong phi elim
loop dependence analysis
CorrelatedValuePropagation
- lib/Transforms/IPO/MergeFunctions.cpp => consider for 3.1.
+ lib/Transforms/IPO/MergeFunctions.cpp => consider for 3.2.
Integrated assembler on by default for arm/thumb?
-->
llvm/lib/Archive - replace with lib object?
-->
-<p>LLVM 3.1 includes several major changes and big features:</p>
+<p>LLVM 3.2 includes several major changes and big features:</p>
<ul>
- <li><a href="../tools/clang/docs/AddressSanitizer.html">AddressSanitizer</a>,
- a fast memory error detector.</li>
- <li><a href="CodeGenerator.html#machineinstrbundle">MachineInstr Bundles</a>,
- Support to model instruction bundling / packing.</li>
- <li><a href="#armintegratedassembler">ARM Integrated Assembler</a>,
- A full featured assembler and direct-to-object support for ARM.</li>
- <li>....</li>
+ <li>...</li>
</ul>
</div>
<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>....</li>
- </ul>
+<ul>
+ <li>Thread local variables may have a specified TLS model. See the
+ <a href="LangRef.html#globalvars">Language Reference Manual</a>.</li>
+ <li>...</li>
+</ul>
+
</div>
<!--=========================================================================-->
<div>
-<p>In addition to many minor performance tweaks and bug fixes, this
- release includes a few major enhancements and additions to the
- optimizers:</p>
+<p>In addition to many minor performance tweaks and bug fixes, this release
+ includes a few major enhancements and additions to the optimizers:</p>
+
+<p> Loop Vectorizer - We've added a loop vectorizer and we are now able to
+ vectorize small loops. The loop vectorizer is disabled by default and
+ can be enabled using the <b>-mllvm -vectorize-loops</b> flag.
+ The SIMD vector width can be specified using the flag
+ <b>-mllvm -force-vector-width=4</b>.
+ The default value is <b>0</b> which means auto-select.
+ <br/>
+ We can now vectorize this function:
+
+ <pre class="doc_code">
+ unsigned sum_arrays(int *A, int *B, int start, int end) {
+ unsigned sum = 0;
+ for (int i = start; i < end; ++i)
+ sum += A[i] + B[i] + i;
+
+ return sum;
+ }
+ </pre>
+
+ We vectorize under the following loops:
+ <ul>
+ <li>The inner most loops must have a single basic block.</li>
+ <li>The number of iterations are known before the loop starts to execute.</li>
+ <li>The loop counter needs to be incremented by one.</li>
+ <li>The loop trip count <b>can</b> be a variable.</li>
+ <li>Loops do <b>not</b> need to start at zero.</li>
+ <li>The induction variable can be used inside the loop.</li>
+ <li>Loop reductions are supported.</li>
+ <li>Arrays with affine access pattern do <b>not</b> need to be marked as 'noalias' and are checked at runtime.</li>
+ <li>...</li>
+ </ul>
+
+</p>
+
+<p>SROA - We've re-written SROA to be significantly more powerful.
+<!-- FIXME: Add more text here... --></p>
<ul>
- <li>The loop unroll pass now is able to unroll loops with run-time trip counts.
- This feature is turned off by default, and is enabled with the
- <code>-unroll-runtime</code> flag.</li>
- <li>A new basic-block autovectorization pass is available. Pass
- <code>-vectorize</code> to run this pass along with some associated
- post-vectorization cleanup passes.</li>
- <li>....</li>
+ <li>Branch weight metadata is preseved through more of the optimizer.</li>
+ <li>...</li>
</ul>
</div>
<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. 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>
+ in. 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>
<ul>
- <li>....</li>
+ <li>...</li>
</ul>
</div>
<div>
-<p>We have changed the way that the Type Legalizer legalizes vectors. The type
- legalizer now attempts to promote integer elements. This enabled the
- implementation of vector-select. Additionally, we see a performance boost on
- workloads which use vectors of chars and shorts, since they are now promoted
- to 32-bit types, which are better supported by the SIMD instruction set.
- Floating point types are still widened as before.</p>
+<p>Stack Coloring - We have implemented a new optimization pass
+ to merge stack objects which are used in disjoin areas of the code.
+ This optimization reduces the required stack space significantly, in cases
+ where it is clear to the optimizer that the stack slot is not shared.
+ We use the lifetime markers to tell the codegen that a certain alloca
+ is used within a region.</p>
+<p> We now merge consecutive loads and stores. </p>
<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>
<ul>
- <li>TableGen can now synthesize register classes that are only needed to
- represent combinations of constraints from instructions and sub-registers.
- The synthetic register classes inherit most of their properties form their
- closest user-defined super-class.</li>
- <li><code>MachineRegisterInfo</code> now allows the reserved registers to be
- frozen when register allocation starts. Target hooks should use the
- <code>MRI->canReserveReg(FramePtr)</code> method to avoid accidentally
- disabling frame pointer elimination during register allocation.</li>
- <li>A new kind of <code>MachineOperand</code> provides a compact
- 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>...</li>
</ul>
<p> We added new TableGen infrastructure to support bundling for
</div>
+<h4>
+<a name="blockplacement">Basic Block Placement</a>
+</h4>
+
+<div>
+
+<p>A probability based block placement and code layout algorithm was added to
+ LLVM's code generator. This layout pass supports probabilities derived from
+ static heuristics as well as source code annotations such as
+ <code>__builtin_expect</code>.</p>
+
+</div>
+
<!--=========================================================================-->
<h3>
<a name="x86">X86-32 and X86-64 Target Improvements</a>
<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>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>...</li>
</ul>
</div>
<p>New features of the ARM target include:</p>
<ul>
- <li>The constant island pass now supports basic block and constant pool entry
- alignments greater than 4 bytes.</li>
- <li>On Darwin, the ARM target now has a full-featured integrated assembler.
- </li>
+ <li>...</li>
</ul>
+<!--_________________________________________________________________________-->
+
<h4>
<a name="armintegratedassembler">ARM Integrated Assembler</a>
</h4>
+
<div>
+
<p>The ARM target now includes a full featured macro assembler, including
-direct-to-object module support for clang. The assembler is currently enabled
-by default for Darwin only pending testing and any additional necessary
-platform specific support for Linux.</p>
+ direct-to-object module support for clang. The assembler is currently enabled
+ by default for Darwin only pending testing and any additional necessary
+ platform specific support for Linux.</p>
<p>Full support is included for Thumb1, Thumb2 and ARM modes, along with
-subtarget and CPU specific extensions for VFP2, VFP3 and NEON.</p>
+ subtarget and CPU specific extensions for VFP2, VFP3 and NEON.</p>
<p>The assembler is Unified Syntax only (see ARM Architecural Reference Manual
-for details). While there is some, and growing, support for pre-unfied (divided)
-syntax, there are still significant gaps in that support.</p>
+ for details). While there is some, and growing, support for pre-unfied
+ (divided) syntax, there are still significant gaps in that support.</p>
+
</div>
</div>
+
<!--=========================================================================-->
<h3>
<a name="MIPS">MIPS Target Improvements</a>
<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>
+<p>New features and major changes in the MIPS target include:</p>
<ul>
- <li>....</li>
+ <li>...</li>
</ul>
+
</div>
<!--=========================================================================-->
<h3>
-<a name="OtherTS">Other Target Specific Improvements</a>
+<a name="PowerPC">PowerPC Target Improvements</a>
</h3>
<div>
-<p>Support for Qualcomm's Hexagon VLIW processor has been added.</p>
-
<ul>
- <li>....</li>
+<p>Many fixes and changes across LLVM (and Clang) for better compliance with
+ the 64-bit PowerPC ELF Application Binary Interface, interoperability with
+ GCC, and overall 64-bit PowerPC support. Some highlights include:</p>
+<ul>
+ <li> MCJIT support added.</li>
+ <li> PPC64 relocation support and (small code model) TOC handling
+ added.</li>
+ <li> Parameter passing and return value fixes (alignment issues,
+ padding, varargs support, proper register usage, odd-sized
+ structure support, float support, extension of return values
+ for i32 return values).</li>
+ <li> Fixes in spill and reload code for vector registers.</li>
+ <li> C++ exception handling enabled.</li>
+ <li> Changes to remediate double-rounding compatibility issues with
+ respect to GCC behavior.</li>
+ <li> Refactoring to disentangle ppc64-elf-linux ABI from Darwin
+ ppc64 ABI support.</li>
+ <li> Assorted new test cases and test case fixes (endian and word
+ size issues).</li>
+ <li> Fixes for big-endian codegen bugs, instruction encodings, and
+ instruction constraints.</li>
+ <li> Implemented -integrated-as support.</li>
+ <li> Additional support for Altivec compare operations.</li>
+ <li> IBM long double support.</li>
+</ul>
+<p>There have also been code generation improvements for both 32- and 64-bit
+ code. Instruction scheduling support for the Freescale e500mc and e5500
+ cores has been added.</p>
+</ul>
+</div>
+<!--=========================================================================-->
+<h3>
+<a name="OtherTS">Other Target Specific Improvements</a>
+</h3>
+
+<div>
+
+<ul>
+ <li>...</li>
</ul>
</div>
<div>
<p>If you're already an LLVM user or developer with out-of-tree changes based on
- LLVM 3.1, this section lists some "gotchas" that you may run into upgrading
+ LLVM 3.2, this section lists some "gotchas" that you may run into upgrading
from the previous release.</p>
<ul>
- <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>
- <li>The <tt>unwind</tt> instruction is now gone. With the introduction of the
- new exception handling system in LLVM 3.0, the <tt>unwind</tt> instruction
- became obsolete.</li>
- <li>....</li>
+ <li>The CellSPU port has been removed. It can still be found in older
+ versions.</li>
+ <li>...</li>
</ul>
</div>
<p>In addition, many APIs have changed in this release. Some of the major
LLVM API changes are:</p>
+<p> We've added a new interface for allowing IR-level passes to access
+ target-specific information. A new IR-level pass, called
+ "TargetTransformInfo" provides a number of low-level interfaces.
+ LSR and LowerInvoke already use the new interface. </p>
+
+<p> The TargetData structure has been renamed to DataLayout and moved to VMCore
+to remove a dependency on Target. </p>
+
<ul>
- <li>Target specific options have been moved from global variables to members
- on the new <code>TargetOptions</code> class, which is local to each
- <code>TargetMachine</code>. As a consequence, the associated flags will
- no longer be accepted by <tt>clang -mllvm</tt>. This includes:
-<ul>
-<li><code>llvm::PrintMachineCode</code></li>
-<li><code>llvm::NoFramePointerElim</code></li>
-<li><code>llvm::NoFramePointerElimNonLeaf</code></li>
-<li><code>llvm::DisableFramePointerElim(const MachineFunction &)</code></li>
-<li><code>llvm::LessPreciseFPMADOption</code></li>
-<li><code>llvm::LessPrecideFPMAD()</code></li>
-<li><code>llvm::NoExcessFPPrecision</code></li>
-<li><code>llvm::UnsafeFPMath</code></li>
-<li><code>llvm::NoInfsFPMath</code></li>
-<li><code>llvm::NoNaNsFPMath</code></li>
-<li><code>llvm::HonorSignDependentRoundingFPMathOption</code></li>
-<li><code>llvm::HonorSignDependentRoundingFPMath()</code></li>
-<li><code>llvm::UseSoftFloat</code></li>
-<li><code>llvm::FloatABIType</code></li>
-<li><code>llvm::NoZerosInBSS</code></li>
-<li><code>llvm::JITExceptionHandling</code></li>
-<li><code>llvm::JITEmitDebugInfo</code></li>
-<li><code>llvm::JITEmitDebugInfoToDisk</code></li>
-<li><code>llvm::GuaranteedTailCallOpt</code></li>
-<li><code>llvm::StackAlignmentOverride</code></li>
-<li><code>llvm::RealignStack</code></li>
-<li><code>llvm::DisableJumpTables</code></li>
-<li><code>llvm::EnableFastISel</code></li>
-<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>...</li>
</ul>
</div>
<p>In addition, some tools have changed in this release. Some of the changes
are:</p>
-
<ul>
- <li>llvm-stress is a command line tool for generating random .ll files to fuzz
- different LLVM components. </li>
- <li>....</li>
+ <li>...</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>...</li>
</ul>
</div>
<p>LLVM is generally a production quality compiler, and is used by a broad range
of applications and shipping in many products. That said, not every
subsystem is as mature as the aggregate, particularly the more obscure
- targets. 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 or ask on the <a
- href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev
- list</a>.</p>
+ targets. 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 or ask on
+ the <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev
+ list</a>.</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
+ 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>