LLVM Weekly - #277, April 22nd 2019

Welcome to the two hundred and seventy-seventh 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

ClangJIT: Enhancing C++ with Just-in-Time Compilation has been published on arXiV. "ClangJIT provides a well-integrated C++ language extension allowing template-based specialization to occur during program execution."

On the mailing lists

• Zola Bridges shares notes from the EuroLLVM Spectre round table.

• Simon Tatham reports that patches providing initial support for ARM v8.1-M and the MVE vector architecture have been posted to Phabricator.

• Gábor Márton provided and update on work to support cross translation unit (CTU) static analyis. It can now be used to analyse a non-trivial project (tmux) without crashes.

• Tanya Lattner is looking for mentors and project ideas for Google Season of Docs. Note that the deadline is 20:00 UTC on April 23rd, so move fast!

• Peter Collingbourne shared an initial version of a tool to help track down binary size regressions, while ignoring changes that occur due to different inlining decisions.

• Alex Denisov is seeking input from other LLVM social organisers in order to produce guidelines for thos who want to set up their own LLVM meetup.

LLVM commits

• A loop fusion pass was introduced. r358607.

• Documentation was added on how variable location metadata is transformed during codegen. r358385.

• Simple common subexpression elimination of constants was enabled in GlobalISel. r358369.

• Profile guided code size optimisation was added, performing code size optimisations for cold code. r358422.

• The RISC-V backend learned to custom-lower {SHL,SRA,SRLA}_PARTS. r358498.

• The llvm::bsearch helper was added to STLExtras. r358540.

Clang commits

• Implementation of C++2a modules continues with the addition of semantic support for private module fragments. r358713.

• clang-tidy was extended to support human-readable fix descriptions, allowing users to know what a fix does without previewing the diff. r358576.

Other project commits

• A simple plugin architecture was added to asan_symbolize.py, allowing arbitrarily complex and deployment-specific code to be used to find binaries with debug symbols. r358657.

• Documentation was added on how to build the LLDB docs. r358777.