Bidding Starts: Wednesday, May 16 , 2024

Bidding Ends: Wednesday, May 29 , 2024

Contract start date: TBD

Summary:

Improvements to compiler codegen is one of the most impactful areas that RISE can help the RISC-V ecosystem. Currently RISC-V compilers need significant improvements relative to other architectures and broad and large gains can be made. RISE is excited to fund a comparison of codegen vs arm64 and use that to drive specific improvements into GCC.

Milestones to Deliver:

Phase 1: Analysis and improvements of SPEC

Codegen improvements in GCC. The company should focus on all or a subset of SPEC 2017. Identify and fix weaknesses to bring RISC-V codegen up to parity with or if possible exceed Aarch64. Larger items identified can be documented (with a code and assembly snippet) without being fixed, at the discretion of the contracting company.
Architectural deficiencies in RISC-V. Identify cases which are primarily driven by differences in the ISA. For example, AArch64 performing better because it has a richer set of addressing modes for vector instructions and similar kinds of issues. Ideally this section would identify the component of spec2017 that is affected, show a C/C++/Fortran code fragment for the problem and the corresponding AArch64 and RISC-V assembly for the fragment.

Here is the Analysis RISE has done.

RISC-V GCC trails arm64 GCC and RISC-V LLVM on a subset of the SPEC 2017 benchmarks. When measuring dynamic instruction counts, some of the larger outliers are:

benchmark	workload #	vs. SVE2
549.fotonik3d_r	0	-79.90%
554.roms_r	0	-73.13%
525.x264_r	1	-62.26%
525.x264_r	2	-58.84%
503.bwaves_r	1	-40.41%
503.bwaves_r	3	-40.05%
503.bwaves_r	0	-39.84%
503.bwaves_r	2	-39.67%
525.x264_r	0	-38.91%
521.wrf_r	0	-36.46%
510.parest_r	0	-26.03%
526.blender_r	0	-17.53%
541.leela_r	0	-13.73%
508.namd_r	0	-12.32%
511.povray_r	0	-11.58%
502.gcc_r	4	-10.52%

We have some known issues, including:

Missing register+register addressing patterns
Email info@riseproject.dev to if you would like to see additional analysis RISE team has done.

The Phase 2 of this Project will be a separated RFP in 2H2024 on additional SPEC benchmark improvements.

Bidding Closed

Browser not supported