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diff --git a/docs/ReleaseNotes.html b/docs/ReleaseNotes.html index 736ef37..9b65c6f 100644 --- a/docs/ReleaseNotes.html +++ b/docs/ReleaseNotes.html @@ -257,6 +257,11 @@ The first dragonegg release will occur shortly after llvm-2.7 is released. The LLVM Machine Code (MC) Toolkit project is ... </p> +<p> +MC Disassembler (with blog post), MCInstPrinter. Many X86 backend and AsmPrinter simplifications +Can transcode from GAS to intel syntax with "llvm-mc foo.s -output-asm-variant=1" +</p> + </div> @@ -380,16 +385,22 @@ organization changes have happened: <ul> <li>LLVM has a new <a href="http://llvm.org/Logo.html">official Logo</a>!</li> -<li><a href="http://llvm.org">llvm.org</a> is now hosted on a new (and much -faster) server. It is still hosted as the University of Illinois.</li> - <li>Ted Kremenek and Doug Gregor have stepped forward as <a href="http://llvm.org/docs/DeveloperPolicy.html#owners">Code Owners</a> of the Clang static analyzer and the Clang Frontend, respectively.</li> - + +<li>LLVM now has an <a href="http://blog.llvm.org">official Blog</a> at + <a href="http://blog.llvm.org">http://blog.llvm.org</a>. This is a great way + to learn about new LLVM-related features as they are implemented. Several + features in this release are already explained on the blog.</li> + <li>The LLVM web pages are now checked into the SVN server, in the "www", "www-pubs" and "www-releases" SVN modules. Previously they were hidden in a largely inaccessible old CVS server.</p> + +<li><a href="http://llvm.org">llvm.org</a> is now hosted on a new (and much + faster) server. It is still graciously hosted at the University of Illinois + of Urbana Champaign.</li> </ul> </div> @@ -403,25 +414,47 @@ faster) server. It is still hosted as the University of Illinois.</li> <p>LLVM 2.7 includes several major new capabilities:</p> <ul> -<li>New MicroBlaze backend. http://en.wikipedia.org/wiki/MicroBlaze</li> - -<li>Extensible metadata solid.</li> - -<li>Debug info improvements: using metadata instead of llvm.dbg global variables. -This brings several enhancements including improved compile times.</li> - -<li>Indirect branch + address of label (blog post), particularly useful for -interpreters.</li> - -<li>New instruction selector.</li> +<li>This release includes initial support for the <a + href="http://en.wikipedia.org/wiki/MicroBlaze">MicroBlaze</a> target. + MicroBlaze is a soft processor core designed for Xilinx FPGAs.</li> + +<li>LLVM 2.7 includes a new LLVM IR "extensible metadata" feature. This feature + supports many different use cases, including allowing front-end authors to + encode source level information into LLVM IR, which is consumed by later + language-specific passes. This is a great way to do high-level optimizations + like devirtualization, type-based alias analysis, etc. See the <a + href="http://blog.llvm.org/2010/04/extensible-metadata-in-llvm-ir.html"> + Extensible Metadata Blog Post</a> for more information.</li> + +<li>LLVM 2.7 encodes <a href="SourceLevelDebugging.html">debug information</a> +in a completely new way, built on extensible metadata. The new implementation +is much more memory efficient and paves the way for improvements to optimized +code debugging experience.</li> + +<li>LLVM 2.7 now directly supports taking the address of a label and doing an + indirect branch through a pointer. This is particularly useful for + interpreter loops, and is used to implement the GCC "address of label" + extension. For more information, see the <a +href="http://blog.llvm.org/2010/01/address-of-label-and-indirect-branches.html"> +Address of Label and Indirect Branches in LLVM IR Blog Post</a>. + +<li>LLVM 2.7 is the first release to start supporting APIs for assembling and + disassembling target machine code. These APIs are useful for a variety of + low level clients, and are surfaced in the new "enhanced disassembly" API. + For more information see the <a + href="http://blog.llvm.org/2010/01/x86-disassembler.html">The X86 + Disassembler Blog Post</a> for more information.</li> + +<li>LLVM 2.7 includes major parts of the work required by the new MC Project, + which aims to rework our handling of low-level machine code. 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 you has made + substantially more progress on LLVM mainline. You can read more about this + in the <a href="http://blog.llvm.org/2010/04/intro-to-llvm-mc-project.html"> + Intro to the LLVM MC Project Blog Post</a>. +</li> </ul> -libllvm2.7.so?? configure with --enable-shared -MC encoding and disassembler apis. -MC Disassembler (with blog post), MCInstPrinter. Many X86 backend and AsmPrinter simplifications -Can transcode from GAS to intel syntax with "llvm-mc foo.s -output-asm-variant=1" - - </div> @@ -435,12 +468,22 @@ Can transcode from GAS to intel syntax with "llvm-mc foo.s -output-asm-variant=1 expose new optimization opportunities:</p> <ul> -<li>New InlineHint and StackAlignment function attributes -Half-float support in APFloat -llvm.objectsize. -New llvm/Support/Regex.h API. FileCheck now does regex's -Pre-Alpha support for unions in IR. -dbgs() and -debug-buffer-size=N +<li>LLVM IR now supports a 16-bit "half float" data type through two new <a + href="LangRef.html#int_fp16">intrinsics</a> and APFloat support.</li> +<li>LLVM IR supports two <a href="LangRef.html#fnattrs">new function + attributes</a>: inlinehint and alignstack(n). The former is a hint to the + optimizer that a function was declared 'inline' and thus it might be useful + to increase the chances the the inliner actually inline it. The later + indicates to the code generator that the function diverges from the platform + ABI on stack alignment.</li> +<li>The new <a href="LangRef.html#int_objectsize">llvm.objectsize</a> intrinsic + allows the optimizer to infer the sizes of memory objects in some cases. + This intrinsic is used to implement the GCC __builtin_object_size + extension.</li> +<li>LLVM 2.7 has pre-alpha support for <a + href="http://llvm.org/docs/LangRef.html#t_union">unions in LLVM IR</a>. + Unfortuantely, this support is not really usable in 2.7, so if you're + interested in pushing it forward, please help contribute to LLVM mainline.</li> </li> </ul> @@ -524,6 +567,7 @@ infrastructure, which allows us to implement more aggressive algorithms and make it run faster:</p> <ul> +<li>New instruction selector [blog post?].</li> Code generator MC'ized except for debug info and EH. @@ -576,12 +620,21 @@ Many improvements to debug info <ul> -<li>complete llvm-gcc NEON support.</li> -<li>ARM/Thumb using reg scavenging for stack object address materialization - (PEI).</li> -<li>The ARM backend now has good support for ARMv4 backend (tested on StrongARM - hardware), previously only supported ARMv4T and newer.</li> -<li>ARM backend generates instructions in unified assembly syntax.</li> +<li>The ARM backend now generates instructions in unified assembly syntax.</li> + +<li>llvm-gcc now has complete support for the ARM v7 NEON instruction set. This + support differs slightly from the GCC implementation. Please see the + <a +href="http://blog.llvm.org/2010/04/arm-advanced-simd-neon-intrinsics-and.html"> + ARM Advanced SIMD (NEON) Intrinsics and Types in LLVM Blog Post</a> for + helpful information if migrating code from GCC to LLVM-GCC.</li> + +<li>The ARM and Thumb code generators now using register scavenging for stack + object address materialization.(FIXME: WHAT BENEFIT DOES THIS PROVIDE?)</li> + +<li>The ARM backend now has good support for ARMv4 targets, and has been tested + on StrongARM hardware. Previously, LLVM only supported ARMv4T and + newer chips.</li> </ul> @@ -614,7 +667,16 @@ Many improvements to debug info </p> <ul> -<li>...</li> +<li>The llvm/Support/Regex.h header exposes a platform independent regular + expression API. Building on this, the <a + href="TestingGuide.html#FileCheck">FileCheck</a> utility now supports + regular exressions.</li> +<li>raw_ostream now supports a circular "debug stream" accessed with "dbgs()". + By default, this stream works the same way as "errs()", but if you pass + <tt>-debug-buffer-size=1000</tt> to opt, the debug stream is capped to a + fixed sized circular buffer and the output is printed at the end of the + program's execution. This is helpful if you have a long lived compiler + process and you're interested in seeing snapshots in time.</li> </ul> @@ -629,6 +691,9 @@ Many improvements to debug info <p>Other miscellaneous features include:</p> <ul> +<li>You can now build LLVM as a big dynamic library (e.g. "libllvm2.7.so"). To + get this, configure LLVM with the --enable-shared option.</li> + <li>LLVM command line tools now overwrite their output by default, before they would only do this with -f. This makes them more convenient to use, and behave more like standard unix tools.</li> |