[PATCH] D139598: [InstCombine] Fold (X << Z) / (X * Y) -> (1 << Z) / Y

[Matt Arsenault via Phabricator via llvm-commits]

arsenm added inline comments.


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Comment at: llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp:1062
+      return BinaryOperator::CreateUDiv(
+          Builder.CreateShl(ConstantInt::get(Ty, 1), Z), Y);
+  }
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Can you preserve NUW and exact?


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Comment at: llvm/test/Transforms/InstCombine/div-shift.ll:556
 }
 
 ; negative test - sdiv
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Vector test? Tests with flag preservation?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D139598/new/

https://reviews.llvm.org/D139598