[llvm] [VectorCombine] Add intrinsics handling to shuffleToIdentity (PR #91000)

[David Green via llvm-commits]

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@@ -1729,7 +1729,9 @@ bool VectorCombine::foldShuffleToIdentity(Instruction &I) {
       return false;
 
     // Look for an identity value.
-    if (Item[0].second == 0 && Item[0].first->getType() == Ty &&
+    if (Item[0].second == 0 &&
+        cast<FixedVectorType>(Item[0].first->getType())->getNumElements() ==
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davemgreen wrote:

My understanding is that we should always remain as Vectors, and nothing will become scalable considering we are looking at shuffles and lanewise instructions.

https://github.com/llvm/llvm-project/pull/91000