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diff --git a/docs/ReleaseNotes.html b/docs/ReleaseNotes.html index a4b1d58..a4c5960 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 3.2 -release.<br> -You may prefer the -<a href="http://llvm.org/releases/3.1/docs/ReleaseNotes.html">LLVM 3.1 -Release Notes</a>.</h1> - <!-- *********************************************************************** --> <h2> <a name="intro">Introduction</a> @@ -46,7 +40,7 @@ Release Notes</a>.</h1> <p>This document contains the release notes for the LLVM Compiler 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 + sub-projects 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> @@ -72,11 +66,12 @@ Release Notes</a>.</h1> <div> -<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> +<p>The LLVM 3.2 distribution currently consists of production-quality code + from the core LLVM repository, which roughly includes the LLVM optimizers, + code generators and supporting tools, as well as Clang, DragonEgg and + compiler-rt sub-project repositories. In addition to this code, the LLVM + Project includes other sub-projects that are in development. Here we + include updates on these sub-projects.</p> <!--=========================================================================--> <h3> @@ -90,18 +85,18 @@ Release Notes</a>.</h1> 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> + creating or integrating with other development tools.</p> <p>In the LLVM 3.2 time-frame, the Clang team has made many improvements. Highlights include:</p> <ul> - <li>...</li> + <li>Improvements to Clang's diagnostics</li> + <li>Support for tls_model attribute</li> + <li>Type safety attributes</li> </ul> <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 + <a href="http://llvm.org/releases/3.2/tools/clang/docs/ReleaseNotes.html">Clang 3.2 release notes.</a></p> <p>If Clang rejects your code but another compiler accepts it, please take a @@ -129,7 +124,10 @@ Release Notes</a>.</h1> <p>The 3.2 release has the following notable changes:</p> <ul> - <li>...</li> + <li>Able to load LLVM plugins such as Polly.</li> + <li>Supports thread-local storage models.</li> + <li>Passes knowledge of variable lifetimes to the LLVM optimizers.</li> + <li>No longer requires GCC to be built with LTO support.</li> </ul> </div> @@ -141,7 +139,8 @@ Release Notes</a>.</h1> <div> -<p>The new LLVM <a href="http://compiler-rt.llvm.org/">compiler-rt project</a> + +<p>The 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 @@ -153,7 +152,11 @@ Release Notes</a>.</h1> <p>The 3.2 release has the following notable changes:</p> <ul> - <li>...</li> + <li><a href="http://llvm.org/releases/3.2/tools/clang/docs/ThreadSanitizer.html">ThreadSanitizer (TSan)</a> - data race detector run-time library for C/C++ has been added.</li> + <li>Improvements to <a href="http://llvm.org/releases/3.2/tools/clang/docs/AddressSanitizer.html">AddressSanitizer</a> including: better portability + (OSX, Android NDK), support for cmake based builds, enhanced error reporting and lots of bug fixes.</li> + <li>Added support for A6 'Swift' CPU.</li> + <li><code>divsi3</code> function has been enhanced to take advantage of a hardware unsigned divide when it is available.</li> </ul> </div> @@ -174,7 +177,9 @@ Release Notes</a>.</h1> <p>The 3.2 release has the following notable changes:</p> <ul> - <li>...</li> + <li>Linux build fixes for clang (see <a href="http://lldb.llvm.org/build.html">Building LLDB</a>)</li> + <li>Some Linux stability and usability improvements</li> + <li>Switch expression evaluation to use MCJIT (from legacy JIT) on Linux</li> </ul> </div> @@ -193,7 +198,15 @@ Release Notes</a>.</h1> <p>Within the LLVM 3.2 time-frame there were the following highlights:</p> <ul> - <li>...</li> + <li> C++11 shared_ptr atomic access API (20.7.2.5) has been implemented.</li> + <li>Applied noexcept and constexpr throughout library.</li> + <li>Improved C++11 conformance in associative container emplace.</li> + <li>Performance improvements in: std::rotate algorithm and I/O.</li> + <li>Operator new/delete and type_infos for exception types moved from libc++ to libc++abi.</li> + <li>Bug fixes in: <code><atomic></code>; vector<code><bool></code> algorithms, + <code><future></code>,<code><tuple></code>, + <code><type_traits></code>,<code><fstream></code>,<code><istream></code>, + <code><iterator></code>, <code><condition_variable></code>,<code><complex></code> as well as visibility fixes. </ul> </div> @@ -212,7 +225,7 @@ Release Notes</a>.</h1> <p>The 3.2 release has the following notable changes:</p> <ul> - <li>...</li> + <li>Bug fixes only, no functional changes.</li> </ul> </div> @@ -227,16 +240,61 @@ Release Notes</a>.</h1> <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). + loop optimizations and automatic parallelization (using the OpenMP run time). Work in the area of automatic SIMD and accelerator code generation was started.</p> <p>Within the LLVM 3.2 time-frame there were the following highlights:</p> <ul> - <li>...</li> + <li>isl, the integer set library used by Polly, was relicensed under the MIT license.</li> + <li>isl based code generation.</li> + <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>Support for FORTRAN and Dragonegg.</li> + <li>OpenMP code generation fixes.</li> +</ul> + +</div> + +<!--=========================================================================--> +<h3> +<a name="StaticAnalyzer">Clang Static Analyzer</a> +</h3> + +<div> + +<p>The <a href="http://clang-analyzer.llvm.org/">Clang Static Analyzer</a> + is an advanced source code analysis tool integrated into Clang that performs + a deep analysis of code to find potential bugs.</p> + +<p>In the LLVM 3.2 release, the static analyzer has made significant improvements + in many areas, with notable highlights such as:</p> + +<ul> + <li>Improved interprocedural analysis within a translation unit (see details below), which greatly amplified the analyzer's ability to find bugs.</li> + <li>New infrastructure to model "well-known" APIs, allowing the analyzer to do a much better job when modeling calls to such functions.</li> + <li>Significant improvements to the APIs to write static analyzer checkers, with a more unified way of representing function/method calls in the checker API. Details can be found in the <a href="http://llvm.org/devmtg/2012-11#talk13">Building a Checker in 24 hours</a> talk. +</ul> + +<p>The release specifically includes notable improvements for Objective-C analysis, including:</p> + +<ul> + <li>Interprocedural analysis for Objective-C methods.</li> + <li>Interprocedural analysis of calls to "blocks".</li> + <li>Precise modeling of GCD APIs such as <tt>dispatch_once</tt> and friends.</li> + <li>Improved support for recently added Objective-C constructs such as array and dictionary literals.</li> +</ul> + +<p>The release specifically includes notable improvements for C++ analysis, including:</p> + +<ul> + <li>Interprocedural analysis for C++ methods (within a translation unit).</li> + <li>More precise modeling of C++ initializers and destructors.</li> </ul> +<p>Finally, this release includes many small improvements to <tt>scan-build</tt>, which can be used to drive the analyzer from the command line or a continuous integration system. This includes a directory-traversal issue, which could cause potential security problems in some cases. We would like to acknowledge Tim Brown of Portcullis Computer Security Ltd for reporting this issue.</p> + </div> </div> @@ -265,6 +323,19 @@ Release Notes</a>.</h1> </div> +<h3>EmbToolkit</h3> + +<div> + +<p><a href="http://www.embtoolkit.org/">EmbToolkit</a> provides Linux cross-compiler + toolchain/SDK (GCC/binutils/C library (uclibc,eglibc,musl)), a build system for + package cross-compilation and optionally various root file systems. + It supports ARM and MIPS. There is an ongoing effort to provide a clang+llvm + environment for the 3.2 releases, +</p> + +</div> + <h3>FAUST</h3> <div> @@ -274,7 +345,7 @@ Release Notes</a>.</h1> 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> + works with LLVM 2.7-3.2.</p> </div> @@ -331,7 +402,11 @@ Release Notes</a>.</h1> <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> + distributed as open source software with the "New BSD" license. + It has been used for all the shading on such films as The Amazing Spider-Man, + Men in Black III, Hotel Transylvania, and may other films in-progress, + and also has been incorporated into several commercial and open source + rendering products such as Blender, VRay, and Autodesk Beast.</p> </div> @@ -367,7 +442,7 @@ Release Notes</a>.</h1> 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 +<p>Pure version 0.56 has been tested and is known to work with LLVM 3.2 (and continues to work with older LLVM releases >= 2.5).</p> </div> @@ -432,7 +507,9 @@ Release Notes</a>.</h1> <p>LLVM 3.2 includes several major changes and big features:</p> <ul> - <li>...</li> + <li>Loop Vectorizer.</li> + <li>New implementation of SROA.</li> + <li>New NVPTX back-end (replacing existing PTX back-end) based on NVIDIA sources.</li> </ul> </div> @@ -451,7 +528,10 @@ Release Notes</a>.</h1> <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> + <li>'TYPE_CODE_FUNCTION_OLD' type code and autoupgrade code for old function attributes format has been removed.</li> + <li>Internal representation of the Attributes class has been converted into a pointer to an + opaque object that's uniqued by and stored in the LLVMContext object. + The Attributes class then becomes a thin wrapper around this opaque object.</li> </ul> </div> @@ -489,23 +569,33 @@ Release Notes</a>.</h1> <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 incrimented by one.</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> +<p>SROA - We’ve re-written SROA to be significantly more powerful and generate +code which is much more friendly to the rest of the optimization pipeline. +Previously this pass had scaling problems that required it to only operate on +relatively small aggregates, and at times it would mistakenly replace a large +aggregate with a single very large integer in order to make it a scalar SSA +value. The result was a large number of i1024 and i2048 values representing any +small stack buffer. These in turn slowed down many subsequent optimization +paths.</p> +<p>The new SROA pass uses a different algorithm that allows it to only promote to +scalars the pieces of the aggregate actively in use. Because of this it doesn’t +require any thresholds. It also always deduces the scalar values from the uses +of the aggregate rather than the specific LLVM type of the aggregate. These +features combine to both optimize more code with the pass but to improve the +compile time of many functions dramatically.</p> <ul> - <li>Branch weight metadata is preseved through more of the optimizer.</li> - <li>...</li> + <li>Branch weight metadata is preserved through more of the optimizer.</li> </ul> </div> @@ -524,8 +614,19 @@ Release Notes</a>.</h1> <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> +<ul> + <li> Added support for following assembler directives: <code>.ifb</code>, <code>.ifnb</code>, <code>.ifc</code>, + <code>.ifnc</code>, <code>.purgem</code>, <code>.rept</code> and <code>.version</code> (ELF) as well as Darwin specific + <code>.pushsection</code>, <code>.popsection</code> and <code>.previous</code> .</li> + <li>Enhanced handling of <code>.lcomm directive</code>.</li> + <li>MS style inline assembler: added implementation of the offset and TYPE operators.</li> + <li>Targets can specify minimum supported NOP size for NOP padding.</li> + <li>ELF improvements: added support for generating ELF objects on Windows.</li> + <li>MachO improvements: symbol-difference variables are marked as N_ABS, added direct-to-object attribute for data-in-code markers.</li> + <li>Added support for annotated disassembly output for x86 and arm targets.</li> + <li>Arm support has been improved by adding support for ARM TARGET2 relocation + and fixing hadling of ARM-style "$d.*" labels.</li> + <li>Implemented local-exec TLS on PowerPC.</li> </ul> </div> @@ -550,10 +651,6 @@ Release Notes</a>.</h1> infrastructure, which allows us to implement more aggressive algorithms and make it run faster:</p> -<ul> - <li>...</li> -</ul> - <p> We added new TableGen infrastructure to support bundling for Very Long Instruction Word (VLIW) architectures. TableGen can now automatically generate a deterministic finite automaton from a VLIW @@ -563,6 +660,13 @@ Release Notes</a>.</h1> <p> We have added a new target independent VLIW packetizer based on the DFA infrastructure to group machine instructions into bundles.</p> +<p> We have added new TableGen infrastructure to support relationship maps + between instructions. This feature enables TableGen to automatically + construct a set of relation tables and query functions that can be used + to switch between various forms of instructions. For more information, + please refer to <a href="http://llvm.org/docs/HowToUseInstrMappings.html"> + How To Use Instruction Mappings</a>.</p> + </div> <h4> @@ -588,7 +692,7 @@ Release Notes</a>.</h1> <p>New features and major changes in the X86 target include:</p> <ul> - <li>...</li> + <li>Small codegen optimizations, especially for AVX2.</li> </ul> </div> @@ -603,7 +707,7 @@ Release Notes</a>.</h1> <p>New features of the ARM target include:</p> <ul> - <li>...</li> + <li>Support and performance tuning for the A6 'Swift' CPU.</li> </ul> <!--_________________________________________________________________________--> @@ -620,7 +724,7 @@ Release Notes</a>.</h1> 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> + sub-target 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 @@ -640,7 +744,29 @@ Release Notes</a>.</h1> <p>New features and major changes in the MIPS target include:</p> <ul> - <li>...</li> + <li>Integrated assembler support: + MIPS32 works for both PIC and static, known limitation is the PR14456 where + R_MIPS_GPREL16 relocation is generated with the wrong addend. + MIPS64 support is incomplete, for example exception handling is not working.</li> + <li>Support for fast calling convention has been added.</li> + <li>Support for Android MIPS toolchain has been added to clang driver.</li> + <li>Added clang driver support for MIPS N32 ABI through "-mabi=n32" option.</li> + <li>MIPS32 and MIPS64 disassembler has been implemented.</li> + <li>Support for compiling programs with large GOTs (exceeding 64kB in size) has been added + through llc option "-mxgot".</li> + <li>Added experimental support for MIPS32 DSP intrinsics.</li> + <li>Experimental support for MIPS16 with following limitations: only soft float is supported, + C++ exceptions are not supported, large stack frames (> 32000 bytes) are not supported, + direct object code emission is not supported only .s .</li> + <li>Standalone assembler (llvm-mc): implementation is in progress and considered experimental.</li> + <li>All classic JIT and MCJIT tests pass on Little and Big Endian MIPS32 platforms.</li> + <li>Inline asm support: all common constraints and operand modifiers have been implemented.</li> + <li>Added tail call optimization support, use llc option "-enable-mips-tail-calls" + or clang options "-mllvm -enable-mips-tail-calls"to enable it.</li> + <li>Improved register allocation by removing registers $fp, $gp, $ra and $at from the list of reserved registers.</li> + <li>Long branch expansion pass has been implemented, which expands branch + instructions with offsets that do not fit in the 16-bit field.</li> + <li>Cavium Octeon II board is used for testing builds (llvm-mips-linux builder).</li> </ul> </div> @@ -652,7 +778,6 @@ Release Notes</a>.</h1> <div> -<ul> <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> @@ -681,8 +806,28 @@ Release Notes</a>.</h1> <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> + +</div> + +<!--=========================================================================--> +<h3> +<a name="NVPTX">PTX/NVPTX Target Improvements</a> +</h3> + +<div> + +<p>The PTX back-end has been replaced by the NVPTX back-end, which is based on + the LLVM back-end used by NVIDIA in their CUDA (nvcc) and OpenCL compiler. + Some highlights include:</p> +<ul> + <li>Compatibility with PTX 3.1 and SM 3.5</li> + <li>Support for NVVM intrinsics as defined in the NVIDIA Compiler SDK</li> + <li>Full compatibility with old PTX back-end, with much greater coverage of + LLVM IR</li> </ul> +<p>Please submit any back-end bugs to the LLVM Bugzilla site.</p> + </div> <!--=========================================================================--> @@ -693,7 +838,7 @@ Release Notes</a>.</h1> <div> <ul> - <li>...</li> + <li>Added support for custom names for library functions in TargetLibraryInfo.</li> </ul> </div> @@ -710,9 +855,11 @@ Release Notes</a>.</h1> from the previous release.</p> <ul> - <li>...</li> -</ul> - +<li>llvm-ld and llvm-stub have been removed, llvm-ld functionality can be partially replaced by + llvm-link | opt | {llc | as, llc -filetype=obj} | ld, or fully replaced by Clang. </li> +<li>MCJIT: added support for inline assembly (requires asm parser), added faux remote target execution to lli option '-remote-mcjit'.</li> +</ul> + </div> <!--=========================================================================--> @@ -733,10 +880,6 @@ Release Notes</a>.</h1> <p> The TargetData structure has been renamed to DataLayout and moved to VMCore to remove a dependency on Target. </p> -<ul> - <li>...</li> -</ul> - </div> <!--=========================================================================--> @@ -746,33 +889,22 @@ to remove a dependency on Target. </p> <div> -<p>In addition, some tools have changed in this release. Some of the changes - are:</p> - -<ul> - <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> +<p>In addition, some tools have changed in this release. Some of the changes are:</p> <ul> - <li>...</li> +<li>opt: added support for '-mtriple' option.</li> +<li>llvm-mc : - added '-disassemble' support for '-show-inst' and '-show-encoding' options, added '-edis' option to produce annotated + disassembly output for X86 and ARM targets.</li> +<li>libprofile: allows the profile data file name to be specified by the LLVMPROF_OUTPUT environment variable.</li> +<li>llvm-objdump: has been changed to display available targets, '-arch' option accepts x86 and x86-64 as valid arch names.</li> +<li>llc and opt: added FMA formation from pairs of FADD + FMUL or FSUB + FMUL enabled by option '-enable-excess-fp-precision' or option '-enable-unsafe-fp-math', + option '-fp-contract' controls the creation by optimizations of fused FP by selecting Fast, Standard, or Strict mode.</li> +<li>llc: object file output from llc is no longer considered experimental.</li> +<li>gold plugin: handles Position Independent Executables.</li> </ul> </div> -</div> <!-- *********************************************************************** --> <h2> @@ -794,7 +926,7 @@ to remove a dependency on Target. </p> <p>Known problem areas include:</p> <ul> - <li>The CellSPU, MSP430, PTX and XCore backends are experimental.</li> + <li>The CellSPU, MSP430, and XCore backends are experimental, and the CellSPU backend will be removed in LLVM 3.3.</li> <li>The integrated assembler, disassembler, and JIT is not supported by several targets. If an integrated assembler is not supported, then a @@ -836,7 +968,7 @@ to remove a dependency on Target. </p> src="http://www.w3.org/Icons/valid-html401-blue" alt="Valid HTML 4.01"></a> <a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br> - Last modified: $Date: 2012-11-20 05:22:44 +0100 (Tue, 20 Nov 2012) $ + Last modified: $Date: 2012-12-19 11:50:28 +0100 (Wed, 19 Dec 2012) $ </address> </body> |
