Alex Bradbury via llvm-dev
2020-Mar-30 19:29 UTC
[llvm-dev] LLVM Weekly - #326, Mar 30th 2020
LLVM Weekly - #326, Mar 30th 2020 ================================ If you prefer, you can read a HTML version of this email at <http://llvmweekly.org/issue/326>. Welcome to the three hundred and twenty-sixth 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 10.0.0 [has been released](http://lists.llvm.org/pipermail/llvm-dev/2020-March/140233.html). As always, thank you to everyone who has contributed in any way! ## On the mailing lists * Kyungwoo Lee wrote an RFC on [homogeneous prolog and epilog for size optimisation in AArch64](http://lists.llvm.org/pipermail/llvm-dev/2020-March/140206.html). This is a code size optimisation that attempts to emit homogeneous stores and loads with the same offset for prolog and epilog in order to increase the benefit of machine outlining. * Philip Reames started a discussion on [the status of Intel JCC mitigations](http://lists.llvm.org/pipermail/llvm-dev/2020-March/140237.html) and the desired next steps. As Philip explains, there is currently a disagreement about how to move forwards. * Anton Bikineev proposes [allowing custom sections to be under `GNU_RELRO`](http://lists.llvm.org/pipermail/llvm-dev/2020-March/140348.html). The motivation is to help security hardening applications that define custom sections. * Louis Dionne started a discussion on [bumping the CMake version requirement for libc++ and libc++abi](http://lists.llvm.org/pipermail/llvm-dev/2020-March/140239.html). This triggered a lot of discussion. * Bardia Mahjour shared [meeting minutes from the March 25th loop optimisation working group meeting](http://lists.llvm.org/pipermail/llvm-dev/2020-March/140283.html). * "Whisperity" posted a proposal for [adding 'experimental' checks to clang-tidy](http://lists.llvm.org/pipermail/cfe-dev/2020-March/064980.html). ## LLVM commits * A new algorithm was added to the LLVM Support library to perform the 'optimal' layout of a struct, and it was put to use for coroutine frames. [49e5a97](https://reviews.llvm.org/rG49e5a97ec36), [9514c048](https://reviews.llvm.org/rG9514c048d89). * MC layer (assembler/disassembler) support was added for Armv8.6-a BFloat16. [71ae267](https://reviews.llvm.org/rG71ae267d1f4). * GlobalISel gained new generic opcodes for saturating add/subtract. [0444d16](https://reviews.llvm.org/rG0444d16a16c). * The FREEZE node was added to the SelectionDAG. [7802be4](https://reviews.llvm.org/rG7802be4a3d8). * The use of `llvm_unreachable` was further clarified in the LLVM coding standards. [4778e40](https://reviews.llvm.org/rG4778e409de1). * Documentation was added on how to deal with issues of slow build time or memory exhaustion when compiling LLVM. [37943e5](https://reviews.llvm.org/rG37943e518c5). ## Clang commits * An attribute plugin example was added. [3f03c12](https://reviews.llvm.org/rG3f03c12a51b). * Support was added for the `cmse_nonsecure_call` and `cmse_nonsecure_entry` Arm CMSE (Cortex-M Security Extensions) attributes. [080d046](https://reviews.llvm.org/rG080d046c91d). * All Arm MVE intrinsics are now implemented. [f282b6a](https://reviews.llvm.org/rGf282b6ab23a). ## Other project commits * LLVM's libc gained a simple x86-64 Linux loader. [f6ccb4f](https://reviews.llvm.org/rGf6ccb4fef24). * `SignalContext::GetWriteFlag`, part of the sanitizer infrastructure, was implemented for RISC-V. [ad1466f](https://reviews.llvm.org/rGad1466f8cbc). * ThinLTO can now use all hardware threads on the system, rather than being limited to one thread per core. [0915825](https://reviews.llvm.org/rG09158252f77). * Parallel loop collapsing was implemented in MLIR. [27c201a](https://reviews.llvm.org/rG27c201aa1d9).