Stream: git-wasmtime

Topic: wasmtime / PR #6876 riscv64: Optimize `bitselect+{i,f}cmp...

Wasmtime GitHub notifications bot (Aug 21 2023 at 23:17):

afonso360 edited PR #6876:

:wave: Hey,

This is a followup to #6874 where f{min,max}_pseudo was removed and replaced it with bitselect+fcmp. Here we optimize that pattern into a mask generation instruction and vmerge.vvm that merges both inputs.

This allows us to avoid the quite long sequence for bitselect (4 instructions) and also vector mask expansion (1 instruction) in these patterns.

For tests here I'm relying mostly on wasmtimes wast testsuite.

Wasmtime GitHub notifications bot (Aug 22 2023 at 16:30):

alexcrichton submitted PR review:

Aha I see, and makes sense, thanks for explaining! In that case I don't think a pattern similar to x64 fits well here, so I think what you've written is the way to go :+1:

Wasmtime GitHub notifications bot (Aug 22 2023 at 17:13):

alexcrichton merged PR #6876.

Last updated: Dec 23 2024 at 12:05 UTC