Alex Bradbury via llvm-dev
2017-May-01 15:14 UTC
[llvm-dev] LLVM Weekly - #174, May 1st 2017
LLVM Weekly - #174, May 1st 2017 =============================== If you prefer, you can read a HTML version of this email at <http://llvmweekly.org/issue/174>. Welcome to the one hundred and seventy-fourth 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](http://asbradbury.org). 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 <asb at asbradbury.org>, or @llvmweekly or @asbradbury on Twitter. ## News and articles from around the web Tanya Lattner is [looking for volunteers](http://lists.llvm.org/pipermail/llvm-dev/2017-April/112336.html) to help with system administration, documentation generation and maintenance, and bugzilla and software management. ## On the mailing lists * James Molloy has written up an [incredibly helpful description of GVNSink](http://lists.llvm.org/pipermail/llvm-dev/2017-April/112471.html), complete with neat ASCII art diagrams. * Peter Collingbourne has written an RFC on [moving the module summary into the irsymtab](http://lists.llvm.org/pipermail/llvm-dev/2017-April/112361.html). * Tom Stellard has [summarised the outstanding merge requests for 4.0.1-rc1](http://lists.llvm.org/pipermail/llvm-dev/2017-April/112426.html). * David Gwyne is [looking for feedback](http://lists.llvm.org/pipermail/llvm-dev/2017-April/112431.html) on his efforts to support the -msave-args command line option on x86-64. * Daniel Berlin [reports](http://lists.llvm.org/pipermail/llvm-dev/2017-April/112481.html) the old SimplifyInstruction API is about to be removed and documents how to update any out-of-tree code. ## LLVM commits * A new, simpler loop unswitching pass has been introduced. [r301576](http://reviews.llvm.org/rL301576). * The scalar evolution verifier should no longer suffers from false positives, though is not yet enabled by default for `EXPENSIVE_CHECKS` builds pending investigation of a failure triggered in the Hexagon tests. [r301146](http://reviews.llvm.org/rL301146). * llvm-xray gained a new graph-diff tool for comparing function graphs produced by llvm-xray graph. [r301160](http://reviews.llvm.org/rL301160). * Size and alignment information of register classes has moved to TargetRegisterInfo. [r301221](http://reviews.llvm.org/rL301221). * The newly added 'speculatable' function attribute indicates a function has no side-effects beyond computing its result and has no undefined behaviour. [r301680](http://reviews.llvm.org/rL301680). ## Clang commits * Initial code generation for OpenMP's 'distribute parallel for' was added. [r301223](http://reviews.llvm.org/rL301223). * More unnecessary UBSan checks have been removed. This time, alignment checks on allocas with known alignment. [r301377](http://reviews.llvm.org/rL301377). ## Other project commits * LLD implemented the `--defsym` command-line option. [r301391](http://reviews.llvm.org/rL301391). * Linking when using LLD's `-Map` option has been sped up significantly. The overhead of this option is now about 3x less than before, based on a benchmark of linking clang. [r301659](http://reviews.llvm.org/rL301659). * Initial APIs for tracing have been added to LLDB. [r301389](http://reviews.llvm.org/rL301389).