[PATCH] D27992: [InstCombine] Canonicalize insert sequences that broadcast a value into a insert + shuffle

[David Majnemer via Phabricator via llvm-commits]

majnemer accepted this revision.
majnemer added a comment.
This revision is now accepted and ready to land.

LGTM



================
Comment at: lib/Transforms/InstCombine/InstCombineVectorOps.cpp:641-645
+  SmallVector<Constant *, 16> Mask(
+      NumElements, ConstantInt::get(Type::getInt32Ty(InsElt.getContext()), 0));
+
+  return new ShuffleVectorInst(InsertFirst, UndefValue::get(VT),
+                               ConstantVector::get(Mask));
----------------
It might be more efficient to do `ConstantAggregateZero::get(VectorType::get(...)` instead.


https://reviews.llvm.org/D27992