LLVM Weekly - #259, December 17th 2018

Welcome to the two hundred and fifty-ninth 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 asb@asbradbury.org, or @llvmweekly or @asbradbury on Twitter.

News and articles from around the web

Jan Hubička wrote up a comparison of Firefox 64 built with GCC and Clang with LTO. As always with Jan's posts, it's a great read. One notable difference is that Clang-produced binaries are substantially larger (48% larger code section) because Clang does little to size-optimize cold regions. Also see the Hacker News thread for more discussion.

On the mailing lists

LLVM commits

A new signed fixed point multiplication intrinsic was introduced. r348912.

bugpoint will now search for 'opt', 'clang' and other executables from the LLVM build rather than just searching the user's PATH. r348734.

The AMDGPU backend gained a new pass to manage the mode register (currently just double precision floating point rounding mode). r348754.

Code-gen for RISC-V FMAs was added. r349023.

The PowerPC instruction definitions were refactored to differentiate between the different varieties of pseudo-instruction. r349044.

Clang commits

Try-catch blocks in constexpr fucntions are now supported, as proposed for C++20. r348789.

Clang learned to support -frecord-command-line , which embeds the driver command-line in an ELF section in the output. r349155.

Other project commits