[PATCH] D77301: [TargetLowering] Improve expansion of FSHL/FSHR

[Jay Foad via Phabricator via llvm-commits]

foad marked an inline comment as done.
foad added inline comments.


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Comment at: llvm/test/CodeGen/X86/fshl.ll:123-124
+; X86-SLOW-NEXT:    shrl %eax
+; X86-SLOW-NEXT:    andb $31, %cl
+; X86-SLOW-NEXT:    xorb $31, %cl
+; X86-SLOW-NEXT:    shrl %cl, %eax
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The `andb` is redundant here and in a bunch of other i32/i64 test cases. I would have thought the simplifyDemandedBits machinery could work that out. Any ideas why this isn't already working?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D77301/new/

https://reviews.llvm.org/D77301