LLVM Weekly - #48, Dec 1st 2014

Welcome to the forty-eighth 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 https://llvmweekly.org and pass it on to anyone else you think may be interested. Please send any tips or feedback to asb@asbradbury.org, or @llvmweekly or @asbradbury on Twitter.

News and articles from around the web

John Regehr has posted an update on the Souper superoptimizer which he and his collaborators have been working on. They have implemented a reducer for Souper optimizations that tries to reduce the optimization to something more minimal. There current results given ~4000 distinct optimisations of which ~1500 LLVM doesn't know how to do. Of course many of these may in fact be covered by a single rule or pass. One of the next steps for Souper is to extend Souper to support the synthesis of instruction sequences. See also the discussion on the llvm mailing list.

The LLVM Blog features a summary of recent advances in loop vectorization for LLVM. This includes diagnostics remarks to get feedback on why loops which aren't vectorized are skipped, the loop pragma directive in Clang, and performance warnings when the directive can't be followed.

The LLVM Haskell Compiler (LHC) has been newly reborn along with its blog. The next steps in development are to provide better support for Haskell2010, give reusable libraries for name resolution and type checking, and to produce human-readable compiler output.

The next LLVM Social in Paris will take place on December 9th.

Intel have published a blog post detailing new X86-specific optimisations in GCC 5.0. You may also be interested in the discussion of this post on Hacker News.

On the mailing lists

LLVM commits

Clang commits

Other project commits

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