Arm Posts Initial Ares CPU Tuning Support For GCC, Helps SPEC Performance By ~1%

Arm continues plumbing the open-source GNU compiler toolchain support for their next-generation "Ares" high-performance server/HPC core.

Back in November they presented the initial Ares compiler patches for GCC. Those patches presented Ares as an ARMv8-based design that has statistical profiling, dot product, and FP16 extensions by default. We've also seen other Ares toolchain patches by Arm developers like the recent GNU Assembler support.

This week the patch was published for initial -mcpu=ares tuning support for the GNU Compiler Collection. That patch provides the initial tuning parameters for the Ares core to help with performance. The patches are considered an initial starting point and not necessarily tuned to their fullest extent, but something good enough that Arm is hoping to see in the upcoming GCC 9 release.

As to the performance of the patch, using the -mcpu=ares tuning helped the SPEC2006 integer performance by about 1.2% while other SPEC tests were seeing improvements of under 1% with the current tuning parameters.