LLVM Weekly - #498, July 17th 2023

Welcome to the four hundred and ninety-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 [email protected], or @llvmweekly or @asbradbury on Twitter, or @[email protected] or @[email protected].

News and articles from around the web and events

The next LLVM Bay Area meetup will take place on July 24th.

Fangrui Song blogged about precompiled headers.

According to the LLVM calendar in the coming week there will be:

• Office hours with the following hosts: Phoebe Wang, Johannes Doerfert, Michal Paskowski, Aaron Ballman.
• Online sync-ups on the following topics: security group public sync-up, OpenMP, Clang C/C++ language working group, Flang, RISC-V, MLIR, LLVM embedded toolchain.
• For more details see the LLVM calendar, getting involved documentation on online sync ups and office hours.

On the forums

• The July 2023 Code of Conduct Transparency Report was published.

• LLVM Foundation board meeting minutes for May 2023 were shared.

• There was quite a lot more discussion on the thread about links to private bug trackers in code and commit messages, starting from this message from Doug Gregor.

• Justin Bogner posted an RFC on moving some translation between DXIL and standard LLVM constructs from the DirectX backend to a transforms library.

• Maksim Levantal advertised that MLIR is now available as a Python wheel.

• Eli Friedman noted issues with llvm::format and suggested paths to correcting them.

• Slides and recordings are available from the recent Open MLIR meetings on pattern matching for library and acceleration instruction rewriting and mlir-query.

• Nicolai Hähnle is seeking more feedback on target type classes for extensibility of LLVM IR.

• Aart Bik shared an RFC for adding sparsity support to OpenXLA StableHLO.

• Jeremy Morse provided an update on the RFC for eliminating debug intrinsics.

LLVM commits

• The combiner match table backend for GlobalISel was added. c0719f3.

• Convergence control intrinsics were introduced. da61c86.

• The -opaque-pointers opt flag was removed. 53717ca.

• MC layer support was committed for the RISC-V Zacas extension. 29f630a.

• Variants of the RISC-V intrinsics were added with rounding mode control. 474e37c, 0009366, and more.

Clang commits

• A libclang guide was written. 12d72e4.

• Builtin floating-point number classification functions are now implemented using llvm.is_fpclass. 7d6c2e1.

• Clang gained support for the unified LTO bitcode frontend. 048a0c2.

• clang-format now supports removing redundant parentheses. 3a6a070.

• The bugprone-switch-missing-default-case clang-tidy check was introduced. 42179bb.

Other project commits

• A new mechanism for DWARFRewriter was added to BOLT. 87fb0ea.

• XRay now has initial support for loongarch64. ef33d6c.

• LLDB gained support for the compact C Type Format (CTF). ee44310, 0e285a1.

• A builtin distinct attribute was added to MLIR, allowing you to associate an attribute with a unique identifier. 728a8d5.