[PATCH] D52548: Stop instcombining introducing undef's in div/rem instructions.

[Roman Lebedev via Phabricator via llvm-commits]

lebedev.ri added inline comments.


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Comment at: lib/Transforms/InstCombine/InstCombineVectorOps.cpp:874
+/// the original vector width.
+static bool ShuffleMaskWidens(Value *V, ArrayRef<int> Mask) {
+  Type *Ty = V->getType();
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I think this should to into `lib/IR/Instructions.cpp`, somewhere around the `ShuffleVectorInst::isIdentityMask()`?
(`isWideningMask()`)


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Comment at: test/Transforms/InstCombine/stop_bad_undef_propagation.ll:4
 
-; For each of the div/rem integer instructions we test 3 different variants for
-; how an undef value could be back propagated:
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Is it intentional that the test coverage changes?


https://reviews.llvm.org/D52548