LLVM Weekly - #266, February 4th 2019

Welcome to the two hundred and sixty-sixth 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

LLVM 8.0.0 RC1 is available.

On the mailing lists

• Tim Northover has written an RFC on supporting arm64_32 for AArch64. This includes AArch64 ILP32 support and support for the custom ABI used to allow armv7k IR to be compiled to be compatible with arm64_32.

• Tom Stellard started an RFC thread on linear history vs merge commits after migrating to git. This generated copious discussion.

• Simon Moll shared an RFC on adding native vector predication support to LLVM. It is accompanied by a prototype implementation.

• Stephen Kelly has revived the discussion on the use of auto in LLVM projects.

• Vedant Kumar is curious about the status of the function merging pass.

• David Greene announces that a much improved 'zipping' tool has been released, to help people migrate their downstream repositories to the new combined git repo.

• Davide Italiano started an RFC thread on the future of pexpect in LLDB.

LLVM commits

• The LLVM WebAssembly backend was updated to use the new exception handling proposal. r352598.

• RISC-V RV64F and RV64D codegen (single and double-precision floating point) support was committed. r352807.

• New variadic avx512 compress/expand intrinsics were added. r352343.

• The SelectionDAG will now work to avoid re-ordering DBG_VALUEs. r352350.

• A new 'apple-latest' CPU alias was added. r352412.

• The in-tree gn build system gained a get.py script to download an use a prebuilt gn. r352420.

• The .align directive now correctly inserts NOPs and the R_RISCV_ALIGN relocation when appropriate for RISC-V. r352616.

• A 'dynamic' parameter was added to the objectsize intrinsic. r352664.

• A new FunctionCallee wrapper type was added. r352791, r352833.

Clang commits

• A new -fapply-gobal-visibility-to-externs option was added. r352391.

• clangd implemented textDocument/declaration from the Language Server Protocol 3.14. r352864.

• clangd gained new interfaces for writing "code tweaks". r352494.

Other project commits

• The CoMD Classical Molecular Dynamics Mini-app was added to the LLVM test suite. This is another DOE proxy app. r352375.

• libFuzzer gained a new experimental performance optimisation, lazy_counters which is off by default. r352700.

• The LLD COFF linker supports range extension thunks for ARM64. r352929.