[PATCH] D108408: [InstCombine] Transform X == 0 ? 0 : X * Y --> X * freeze(Y).

[Nikita Popov via Phabricator via llvm-commits]

nikic added inline comments.


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Comment at: llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp:750
+    Mul = BinaryOperator::CreateMul(X, Builder.CreateFreeze(Y));
+  else
+    Mul = BinaryOperator::CreateMul(Builder.CreateFreeze(X), Y);
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What ensures that the other case is `Y == CmpLHS`? Couldn't this be comparing a completely unrelated value?


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Comment at: llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp:753
+  Mul->copyIRFlags(cast<Instruction>(FalseVal));
+  FalseVal->replaceAllUsesWith(Mul);
+  return Mul;
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In InstCombine, replaceInstUsesWith should be used in place of replaceAllUsesWith for worklist management reasons.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D108408/new/

https://reviews.llvm.org/D108408