[PATCH] D146699: [GuardWidening] Freeze the introduced use.

[Max Kazantsev via Phabricator via llvm-commits]

mkazantsev accepted this revision.
mkazantsev added inline comments.
This revision is now accepted and ready to land.


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Comment at: llvm/lib/Transforms/Scalar/GuardWidening.cpp:582
+          Instruction *User = cast<Instruction>(U);
+          return Res != User && DT.dominates(I, User) &&
+                 !DT.dominates(Res, User);
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skatkov wrote:
> mkazantsev wrote:
> > `I` by default should dominate all its users. What am I missing here?
> No, if the user is a phi node in header.
Ok, got it.


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Comment at: llvm/lib/Transforms/Scalar/GuardWidening.cpp:611
+    Instruction *I = dyn_cast<Instruction>(V);
+    if (!I || canCreateUndefOrPoison(cast<Operator>(I),
+                                     /*ConsiderFlagsAndMetadata*/ false)) {
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skatkov wrote:
> mkazantsev wrote:
> > Why we can always cast this to operator? What if it's not?
> Any Instruction can be casted to Operator.
Ok, I see how it works.


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https://reviews.llvm.org/D146699