LLVM Weekly - #373, February 22nd 2021

Welcome to the three hundred and seventy-third 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 LLVM Foundation is intending to sponsor one or more internships through Outreachy this year and is seeking mentors and project suggestions.

LLVM 11.1.0-final has been tagged.

On the mailing lists

• Choongwoo Han posted an RFC on adding support for regex-based path remapping for llvm-cov. Petr Hosek pointed to another solution to dealing with differing source directories on different build machines.

• Tome Stellard posted an updated on 12.0.0 release status listing bugs being tracked for release.

• Wei Wu sought pointers to superoptimization projects, particularly RISC-V related and received a number of answers.

• LLVM GPU News Issue #6 is out.

• In response to a question, Michael Kruse cleared up some confusion about LoopIDs in LLVM.

• Wei Wu asked for advice on the main passes a new LLVM developer should be taught about.

• Geoffrey Martin-Noble sent out a reminder that the review period for the proposal to add a Bazel build configuration to the LLVM monorepo closes this Tuesday.

• Momchil Velikov is seeking feedback on options to better control parameter alignment in LLVM IR.

LLVM commits

• Frame handling and spilling for the RISC-V V extension was added. 5a31a67, a3c783d.

• 'ehcont' section support was added to prepare for Windows Control-flow Enforcement Technology enablement. This section contains exception continuation information. 0808664.

• A new llvm.experimental.vector.reverse intrinsic was added. 2d728bb.

• GPUDivergenceAnalysis was ported to the new pass manager as DivergenceJ4Analysis. 11bf7da.

• Lit gained an early_tests config option to allow the slowest tests to run first, which can improve total testing time on multi-core systems. 161e826.

• The debugify utility can now test the preservation of pre-existing debug info metadata. 1a2b353.

Clang commits

• clang-format gained support for BasedOnStyle: InheritParentConfig which will search for a .clang-format file in the parent directory. 25f753c.

• #pragma omp tile support was implemented. 6c05005.

• CompilerInvocation parsing/generation was documented. 8ddfcec.

• Definitions were added for RISC-V V extension builtin types. 766ee10.

Other project commits

• Debug dump options were added to the flang driver. 4bd08da.

• LLVM's libc gained implementations of the remaining fenv functions (fgetexceptflag, fsetexceptflag, fegetenv, fesetenv, feholdexcept, feupdateenv). b7e05c8.

• The 'legacy' LLDB FreeBSD plugin was removed, and FreeBSDRemote renamed to FreeBSD. cd44339, bee4d6e.

• The whole LLVM openmp project was clang-formatted. 309b00a.