LLVM Weekly - #470, January 2nd 2023
Welcome to the four hundred and seventieth 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 http://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.
Happy New Year and thank you to everyone for reading and contributing to LLVM Weekly with tips and pointers to relevant items (or indeed positive feedback and kind words!). As usual for this time of year, this edition is rather light as LLVM development slowed down substantially over the holidays. I started the newsletter all the way back at the beginning of January 2014 and have managed to avoid missing a Monday since. Onwards and upwards in 2023 - which should see exciting milestones such as the 500th issue, the 512th issue, and of course the 10th anniversary edition at the beginning of 2024…
News and articles from around the web and events
According to the LLVM calendar in the coming week there will be:
- Office hours with the following hosts: Paulo Matos, Tobias Grosser, Johannes Doerfert.
- Online sync-ups on the following topics: OpenMP, C/C++ Clang working group, Flang, OpenMP, RISC-V, MLIR, embedded toolchain working group, HLSL, SPIR-V, MLGO, GPU working group.
- For more details see the LLVM calendar, getting involved documentation on online sync ups and office hours.
On the forums
Alex Zinenko suggests documenting when something isn’t added to MLIR for a particular reason, in order to reduce the number of questions about the absence of such a feature.
Slava Zakharin started an RFC thread on supporting TBAA metadata in the LLVMIR MLIR dialect.
“hdoc” posted an RFC on extending ASTMatchers to support C++20 concepts.
Kai Luo proposed the addition of logic to eliminate spill copies in MachineCopyPropagation.
LLVM commits
The initial series of patches adding an Xtensa backend were committed. 8c618e8, 310f765, 52804a7, and more.
Changes to the code of conduct were committed that clarify behaviour outside of LLVM spaces. bb778cf.
MC layer support was added for the RISC-V XTHeadVdot extension. 54752f3.
Clang commits
The
__GCC_HAVE_SYNC_COMPARE_AND_SWAPmacros are now defined for the M68k target. 2784b24.Builtins were added for
llvm.amdgcn.ballot. f4bcd7f.