[llvm] [VectorCombine] Add support for zext/sext/trunc to shuffleToIdentity (PR #92696)

[David Green via llvm-commits]

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@@ -1753,8 +1756,7 @@ static Value *generateNewInstTree(ArrayRef<InstLane> Item, FixedVectorType *Ty,
 // do so.
 bool VectorCombine::foldShuffleToIdentity(Instruction &I) {
   auto *Ty = dyn_cast<FixedVectorType>(I.getType());
-  if (!Ty || !isa<Instruction>(I.getOperand(0)) ||
-      !isa<Instruction>(I.getOperand(1)))
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davemgreen wrote:

Sure - I can split it out. It will be needed for many of the tests, but there should be enough to test various cases still.

https://github.com/llvm/llvm-project/pull/92696