alexcrichton opened PR #5797 from improve-x64-constant-vec-shifts
to main
:
I stumbled across this working on #5795 and figured this was a nice opportunity to improve the codegen here.
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alexcrichton submitted PR review.
alexcrichton created PR review comment:
I'll admit I don't know what's happening here. This I believe is the constant pool area and capstone is trying to decode it as instructions, but I don't know why after this change, which should generate a smaller constant pool, is generating more instructions here. I would hazard a guess that capstone automatically stoped beforehand for some reason and now it's keeping-on-going, but I'm not sure.
jameysharp submitted PR review.
jameysharp created PR review comment:
I think this is at least partially the same issue that @elliottt is tackling in #5798. We've discussed ways to entirely quit trying to disassemble constants since we think the machbuffer knows where they are, but one step at a time.
alexcrichton updated PR #5797 from improve-x64-constant-vec-shifts
to main
.
jameysharp submitted PR review.
jameysharp created PR review comment:
Since #5798 is merged, can you try rebasing and see if the filetests look any better now?
jameysharp submitted PR review.
jameysharp created PR review comment:
Nevermind, I see you already did and it looks like it didn't help. I'm going to declare that this is harmless and move on with reviewing the rest of this PR.
jameysharp submitted PR review.
alexcrichton updated PR #5797 from improve-x64-constant-vec-shifts
to main
.
alexcrichton has enabled auto merge for PR #5797.
alexcrichton merged PR #5797.
Last updated: Dec 23 2024 at 12:05 UTC