LLVM Weekly - #222, Apr 2nd 2018

Welcome to the two hundred and twenty-second 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

Neil Henning has written a short post on how to read and write LLVM bitcode.

On the mailing lists

• Yaxun (Sam) Liu proposes adding a HIP language mode to Clang. HIP is a language with similarities to CUDA.

• Michael Spencer proposes using Markdown for LLVM documentation.

• Hsiangkai Wang is seeking feedback on an RFC to generate debug info for labels in a function.

• LLVM 5.0.2-rc2 has been tagged.

• Daniel Neilson has reported back on recent work to update memcpy/memmove/memset to have destination and source alignment attributes.

LLVM commits

• An extra InstCombine optimisation improved zlib performance by up to 10%. r328539.

• The LLVM library was renamed from libLLVM-X.Y to libLLVM-X, as the minor version is no longer used in releases. r328768.

• llvm-pdbutil diff mode has been deleted. r328562.

• LLVM assembly output will now use .set instead of = when printing an assignment. r328635.

• Rudimentary support was added for auto-vectorisation for Hexagon's HVX. r328639.

Clang commits

• Named return value optimisation (NRVO) was generalised to cover C structs. r328809.

• The Clang analyzer will now avoid modeling C++17 constructors that aren't fully supported. r328893.

Other project commits

• A new summarizeStats.py utility was added to the OpenMP repository. This processes raw data provided by an instrumented OpenMP runtime library to produce graphs and a CSV file. r328568.

• LLD gained support for MIN and MAX in linker scripts. r328696.

• LLD now supports short thunks on ARM. This reduces the size of Chromium for Android's .text section by 160KB. r328846.