Alex Bradbury via llvm-dev
2019-May-20 19:26 UTC
[llvm-dev] LLVM Weekly - #281, May 20th 2019
LLVM Weekly - #281, May 20th 2019 ================================ If you prefer, you can read a HTML version of this email at <http://llvmweekly.org/issue/281>. Welcome to the two hundred and eighty-first 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](https://www.linkedin.com/in/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 <asb at asbradbury.org>, or @llvmweekly or @asbradbury on Twitter. Readers may be interested in recent news about lowRISC, the not-for-profit open source engineering organisation I co-founded. This is an exciting step forwards on our open source hardware mission. See the coverage on the [Google Open Source blog](https://opensource.googleblog.com/2019/05/google-fosters-open-source-hardware.html) and our own [press release](https://www.lowrisc.org/blog/2019/05/lowrisc-expands-press-release/). ## News and articles from around the web LLVM 8.0.1-rc1 [has been tagged](http://lists.llvm.org/pipermail/llvm-dev/2019-May/132465.html). An LLVM meetup will take place in Leuven, Belgium on [Wednesday June 19th](http://lists.llvm.org/pipermail/llvm-dev/2019-May/132509.html). The 6th HelloLLVM/HelloGCC social in Beijing, China will [take place](http://lists.llvm.org/pipermail/llvm-dev/2019-May/132375.html) on May 25th. ## On the mailing lists * Sander De Smalen has [updated his RFC thread on changes to llvm.experimental.vector.reduce intrinsics](http://lists.llvm.org/pipermail/llvm-dev/2019-May/132455.html) with a summary of feedback so far. * Will Bundy [gave detailed feedback](http://lists.llvm.org/pipermail/llvm-dev/2019-May/132432.html) to the RFC on extending optimisation reporting, based on work done in this area at Sony Playstation. * Jesper Antonsson [summarises](http://lists.llvm.org/pipermail/llvm-dev/2019-May/132395.html) the responses to the RFC on better supporting targets where bytes are not 8 bits. * Louis Dionne has [shared a proposal](http://lists.llvm.org/pipermail/libcxx-dev/2019-May/000358.html) on how to better handle experimental features in libc++, and is seeking feedback. * Sam McCall [proposes](http://lists.llvm.org/pipermail/cfe-dev/2019-May/062262.html) adding RecoveryExpr to represent invalid constructs in the Clang AST. * Artem Dergachev has exhaustively listed the [status of 'alpha' Clang checkers](http://lists.llvm.org/pipermail/cfe-dev/2019-May/062298.html). ## LLVM commits * An initial ORC design document was committed. [r361089](https://reviews.llvm.org/rL361089). * Support in ELF for "dependent libraries" was committed, intended to support simple "autolinking" use cases. [r360984](https://reviews.llvm.org/rL360984). * The SystemZ backend was updated to start to model the floating-point control register. [r360570](https://reviews.llvm.org/rL360570). * Basic target feature definitions were added for Arm SVE2 as well as initial MC layer support. [r360573](https://reviews.llvm.org/rL360573), [r360682](https://reviews.llvm.org/rL360682), and more. * Constrained fptrunc and fpext intrinsics were added. [r360581](https://reviews.llvm.org/rL360581). * The in-tree gn build system can now build the Lanai, Sparc, and Hexagon backends. [r360644](https://reviews.llvm.org/rL360644), [r360645](https://reviews.llvm.org/rL360645), [r360647](https://reviews.llvm.org/rL360647). * Guidelines and recommendations for LLVM socials were added to the LLVM docs. [r360651](https://reviews.llvm.org/rL360651). * HWASan and Kernel HWASan were ported to the new pass manager. [r360707](https://reviews.llvm.org/rL360707). * In order to fix a layering problem, backends were modified to have a new TargetInfo header. [r360709](https://reviews.llvm.org/rL360709), and more. * A scheduling model for the Cortex-M4 was added. [r360768](https://reviews.llvm.org/rL360768). * lround/llround intrinsics and SelectionDAG nodes were added. [r360889](https://reviews.llvm.org/rL360889). ## Clang commits * Virtual function calls and `dynamic_cast` can now be used in constant expression evaluation in C++20.[r360635](https://reviews.llvm.org/rL360635), [r360806](https://reviews.llvm.org/rL360806). * The Clang AST can now be dumped to JSON. [r360622](https://reviews.llvm.org/rL360622). * A new language mode was added for C2x, with `[[attribute]]` support enabled by default. [r360667](https://reviews.llvm.org/rL360667). * A new bugprone-branch-clone check was added to clang-tiy, which detects if/else chains or swtich statements where consecutive branches contain identical code. [r360779](https://reviews.llvm.org/rL360779). ## Other project commits * LLD gained support for `-n` and to disable page alignment and `-N` to both disable page alignment and mark the executable segment as writable. [r360593](https://reviews.llvm.org/rL360593). * lldb-server now works with ipv6. [r361079](https://reviews.llvm.org/rL361079).