[PATCH] D125321: [InstCombine] Freeze other uses of frozen value

[Nikita Popov via Phabricator via llvm-commits]

nikic added inline comments.


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Comment at: llvm/lib/Transforms/InstCombine/InstructionCombining.cpp:3816
 
-  bool Changed = false;
+  // Find the nearest common dominator of all uses of Op.
+  Instruction *Dom = nullptr;
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mtrofin wrote:
> wouldn't going to the def of `Op` be sufficient and compile-time cheaper?
Yes, that would work as well. The reason I went for the nearest common dominator is to avoid hoisting the freeze more than necessary, e.g. out of a loop. Though now that I write that, LICM would do that anyway, so probably that concern doesn't make sense.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D125321/new/

https://reviews.llvm.org/D125321