LLVM Weekly - #112, Feb 22nd 2016
Welcome to the one hundred and twelfth issue of LLVM Weekly, a weekly newsletter (published every Monday) covering developments in LLVM, Clang, and related projects. LLVM Weekly is brought to you by Alex Bradbury. Subscribe to future issues at http://llvmweekly.org and pass it on to anyone else you think may be interested. Please send any tips or feedback to firstname.lastname@example.org, or @llvmweekly or @asbradbury on Twitter.
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News and articles from around the web
Version 0.17.0 of LDC, the LLVM-based compiler for the D programming language has been released. You can view a detailed changelog here.
GCC6 will feature a whole bunch of new warnings, and this blog post details many of them.
The schedule for EuroLLVM 2016 has now been posted. This will be held March 17th-18th in Barcelona.
On the mailing lists
Sanjoy Das has posted an RFC on adding guard intrinsics to LLVM. These would be used in a similar way to the Check opcode in WebKit's new B3 compiler.
Alina Sbirlea proposes adding bitcode tests to the LLVM test-suite. Hal Finkel suggests going further and just pulling Halide in to the LLVM test-suite as a front-end example that should provide greater test coverage.
Andrew Trick shared some thoughts on LLVM in light of the WebKit B3 announcement. "Even when LLVM's compile time problems are largely solved, and I believe they can be, there will always be systemic compile time and memory overhead from design decisions that achieve generality, flexibility, and layering. These are software engineering tradeoffs."
The PPCLoopDataPrefetch pass has been moved to Transforms/Scalar/LoopDataPrefetch in preparation for it becoming a target-agnostic pass. r261265.
The cmpxchg LLVM instruction now allows pointer type operands. r261281.
The X86 backend gained support for a new stack symbol ordering optimisation. This is primarily intended to reduce code size, and produces small but measurable improvements across some SPEC CPU 2000 benchmarks. r260917.
The LLVM C API has been extended to allow it to be used to manipulate the datalayout. r260936.
Some major work on the LazyCallGraph has been checked in. r261040.
The AMDGPU backend gained a basic disassembler. r261185.
The PostOrderFuctionAttrs pass has been ported to the new pass manager. As described in the commit message, this actually represents a major milestone. r261203.
The Hexagon backend gained support for thread-local storage. r261218.
A nullPointerConstant AST matcher was added. r261008.
Clang gained a
-Wcommawarning, which will warn for most uses of the builtin comma operator. r261278