Alex Bradbury via llvm-dev
2021-Apr-19 16:38 UTC
[llvm-dev] LLVM Weekly - #381, April 19th 2021
LLVM Weekly - #381, April 19th 2021 ================================== If you prefer, you can read a HTML version of this email at <http://llvmweekly.org/issue/381>. Welcome to the three 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. ## News and articles from around the web LLVM 12.0.0 [has been released](https://lists.llvm.org/pipermail/llvm-announce/2021-April/000092.html). As always, thank you and congratulations to everyone involved. Michał Górny has written a blog post on [adding support for fork(2) and vfork(2) to LLDB](https://www.moritz.systems/blog/lldb-support-for-fork-and-vfork/), in order to provide follow-[v]fork functionality on par with GNU GDB. ## On the mailing lists * ORC JIT Weekly #32 [provides a preview of the ORC runtime](https://lists.llvm.org/pipermail/llvm-dev/2021-April/149729.html). Lang Hames has also [proposed the ORC runtime library for inclusion in compiler-rt](https://lists.llvm.org/pipermail/llvm-dev/2021-April/149748.html). * LLVM GPU News Issue #10 [is out](https://lists.llvm.org/pipermail/llvm-dev/2021-April/149958.html). * Kristof Beyls announced a [regular LLVM sync-up call on pointer authentication](https://lists.llvm.org/pipermail/llvm-dev/2021-April/149929.html). * Haowei Wu posted an RFC on [generating LLD reproducers on crashes](https://lists.llvm.org/pipermail/llvm-dev/2021-April/149853.html). Fangrui Song [pointed out](https://lists.llvm.org/pipermail/llvm-dev/2021-April/149916.html) that crash reporting is easier to implement in a shell script rather than the LLD * Chen Liue proposed [always emitting unaligned vector move instructions on AVX machines](https://lists.llvm.org/pipermail/llvm-dev/2021-April/149838.html), with an options to disable this behaviour. Some respondents [had concerns](https://lists.llvm.org/pipermail/llvm-dev/2021-April/149841.html). process itself. * Yevgeny Rouban [proposed intrinsics to get the base pointer and offset of GC pointers](https://lists.llvm.org/pipermail/llvm-dev/2021-April/149813.html). * Xiang Zhiang posted on RFC on [supporting AMX faster register allocation at O0](https://lists.llvm.org/pipermail/llvm-dev/2021-April/149813.html). ## LLVM commits * llvm.expect intrinsics are now lowered before running simplifycfg. [661cc71](https://reviews.llvm.org/rG661cc71a1c50). * A pass was added to convert lookup tables to relative lookup tables in order to make them PIC-friendly. [e96df3e](https://reviews.llvm.org/rGe96df3e531f5). * The M68k assembly parser was committed. [6e098e1](https://reviews.llvm.org/rG6e098e133dc7). * llvm-objdump's command-line parsing was migrated from llvm::cl to OptTable. [1035123](https://reviews.llvm.org/rG1035123ac50d). * The PowerPC backend gained MC-layer support for new ROP protection instructions introduced in Power 10. [f28cb01](https://reviews.llvm.org/rGf28cb01be071). * The LLVM language reference was extended to clarify the semantics of 'nocapture'. [1bcadb0](https://reviews.llvm.org/rG1bcadb0984e7). * The semantics of 'nofree' were clarified. [ff55d01](https://reviews.llvm.org/rGff55d01a8e1b). ## Clang commits * The newly introduced `[[clang::musttail]]` attribute can be used for guaranteed tail calls. [8344675](https://reviews.llvm.org/rG834467590842). * A new clang-tidy check 'bugprone-unhandled-exception-at-new' was added to find calls to `new` with a missing exception handler for `std::bad_alloc`. [530456c](https://reviews.llvm.org/rG530456caf908). * clang-rename can now handle designated initialisers. [7dd6068](https://reviews.llvm.org/rG7dd606889925). * clang-tidy gained a check for implicit widening of a multiplication result. [46b8ea2](https://reviews.llvm.org/rG46b8ea2fff90). ## Other project commits * The lld-macho linker gained support for arm64_32. [3bc88eb](https://reviews.llvm.org/rG3bc88eb3924f). * Endianness detection support was implemented in LLVM's libc. [7e075ad](https://reviews.llvm.org/rG7e075ad0b261). * Implementation of ranges started in libc++. [01ace07](https://reviews.llvm.org/rG01ace074fcb6).