[PATCH] D100085: [X86] Support -march=rocketlake

Thu Apr 8 18:58:25 PDT 2021

FreddyYe added inline comments.

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Comment at: llvm/lib/Target/X86/X86.td:790
+                                                  FeatureFSRM];
+  list<SubtargetFeature> RKLTuning = ICLTuning;
+  list<SubtargetFeature> RKLFeatures =
----------------
RKSimon wrote:
> Using ICLTuning suggests we should still be avoiding 512-bit ops (FeaturePrefer256Bit) - is this still true for RKL (or anything past CNL...)?
> 
> I posted PR48336 but never got any response, but from what others have reported (Travis Downs, Phoronix etc) its mainly a power issue these days, not a perf issue due to big freq drops.
We need more tests on such as SPEC to see whether we can default enable FeaturePrefer512bit.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D100085/new/

https://reviews.llvm.org/D100085