LLVM Weekly - #558, September 9th 2024
Welcome to the five hundred and fifty-eighth 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, @llvmweekly or @asbradbury on Twitter, or @llvmweekly@fosstodon.org or @asb@fosstodon.org.
News and articles from around the web and events
The 2024 LLVM Developers' Meeting program has been released.
LLVM 19.1.0-rc4 was released, and 19.1.0-final is planned for 17th September.
A number of blog posts about LLVM GSoC projects are now available: GPU libc benchmarking, half-precision in LLVM libc, and compiling GPU kernels using ClangIR.
According to the LLVM calendar in the coming week there will be the following:
- Office hours with the following hosts: Alexey Bader, Aaron Ballman, Alina Sbirlea, Kristof Beyls, Johannes Doerfert,
- Online sync-ups on the following topics: MLIR C/C++ frontend, alias analysis, pointer authentication, SPIR-V, new contributors, OpenMP, Flang, BOLT, RISC-V, MLIR, embedded toolchains, MLGO.
- For more details see the LLVM calendar, getting involved documentation on online sync ups and office hours.
On the forums
Marc Auberer started a discussion on making DenseMap and DenseSet robust against out of memory situations (motivated by an in-memory database use case where crashes may lead to data loss).
Reid Kleckner provided an update on the AI tool usage in contributions RFC.
Tyler Nowicki posted an RFC on introducing ABI objects for coroutines.
Victor Campos proposed an extension of multilib to support selection of library variants that don’t correspond to command-line options.
Rahul Joshi shared a PSA on planned changes to TableGen getAllDerivedDefinitions.
The LLVM Foundation is hiring a Program Director.
“Yshaneh” asked about adding vararg support for a custom backend and received a range of answers.
LLVM commits
BasicAA learned to track the nuw flag through decomposed expressions. b9bba6c.
spirv-sim, a minimal SPIR-V simulator in Python was added for testing purposes. 5914566.
Support was added for AVX10.2-BF16 X86 instructions. 83ad644.
The initialisation performance of APInt was improved. 427e202.
-verify-eachwas added tollc. 69657eb.With the
-emit-jump-table-sizes-sectionoption, LLVM will emit a.llvm_jump_table_sizessection in the output binary containing jump table addresses and entry counts. This may be used by tools that statically reconstruct the control flow of executables. fb6c10d.usub_{cond,sat}operations were added toatomicrmw. 4af249f.
Clang commits
multilib.yaml now allows you to map a particular multilib to an informative error message. 26bf0b4.
BPF now defaults to the “v3” CPU target. 7852ebc.