LLVM Weekly - #402, September 13th 2021
Welcome to the four hundred and second 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
The call for proposals for the LLVM Distributors Conf 2021 closes on September 16th.
On the mailing lists
Saleem Abdulrasool kicked off a discussion on supporting LLVM_BUILD_LLVM_DYLIB on Windows, with the goal of enabling smaller LLVM distributions for Windows due to the use of dynamic linking. Peter Collingbourne suggested exploring alternate solutions such as multicall binaries
13.0.0-rc3 is running slightly late, and should be out today.
Serge Pavolv created a thread on whether isnan should be optimized out in fast-math mode, and followed up with a summary of pros/cons on the alternatives.
Philipp Reames shared a list of common false positive notifications for commits, e.g. from flaky or slow builders.
Zixu Wang explains why clang-doc doesn’t fill the same gap as clang-extract-api.
LLVM GPU News #19 is out.
Mugilan Ganesan proposes adding a globalmemonly attribute for functions that only access global memory.
ORC JIT Weekly #39 is out, including coverage of support for SimpleRemoteEPC.
LLVM commits
It’s now forbidden to mix typed and opaque pointers (on the grounds that mixing them introduces new issues and isn’t particularly useful). 90ec6df.
The IR similarity tool and analyses gained support for recognising branch similarity. bd4b1b5.
MCAsmBackend::writeNopData now takes an MCSubtargetInfo, allowing the encoding for a nop to chnage depending on the subtarget. e63455d.
The IROutliner can now outline single entry/single exit multiblock regions, and also gained support for multiple exits. 81d3ac0, c172f1a.
Naming of APInt APIs was revised (though old entrypoints have not been removed). A similar change has been made to ConstantSDNode. 735f467, 9af8f1b.
APInt now supports zero bit integers. 704a395.
Initial support was added for .insn in RISC-V. 2838797.
Clang commits
A new cppcoreguidelines-virtual-base-class-destructor check was added to clang-tidy, finding base classes and structs whose destructor is neither public and virtual nor protected and non-virtual. c58c7a6.
clang-nvlink-wrapper was documented. e158363.