SUSE Developer Working On AMD Zen Tuning For GCC

Veteran GCC contributor and SUSE developer Jan Hubicka has begun working on some Zen tuning within the GNU Compiler Collection for benefiting the Ryzen / Threadripper / Epyc processors.

While GCC has already had the "znver1" scheduler model and some tuning for this new CPU microarchitecture, tuning a complicated compiler stack is a virtually never-ending process, just as the LLVM/Clang znver1 support continues to be refined too. AMD has long partnered with SUSE for compiler engineering excellence from working on GCC HSA code to the initial x86_64 bring-up and much more over the years. Given Hubicka now working on Zen tuning, this looks to be the latest involvement.

Jan sent out a GCC patch today via Zen tuning part 1 (reassociation width). This is just the first step and is working on reassociation of integer and vector operations for Zen. Already the initial work has landed in the GCC 8.0 SVN development code.

No performance results were reported for this initial work but he does note of a possible small regression in at least some cases. I'll have more znver1 compiler benchmarks coming up on Phoronix within the next few weeks.