[llvm] [VectorCombine] Generalize foldBitOpOfBitcasts to support more cast operations (PR #148350)

[Rahul Yadav via llvm-commits]

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@@ -862,8 +901,15 @@ bool VectorCombine::foldBitOpOfBitcasts(Instruction &I) {
 
   Worklist.pushValue(NewOp);
 
-  // Bitcast the result back
-  Value *Result = Builder.CreateBitCast(NewOp, I.getType());
+  // Create the cast operation
+  Value *Result = Builder.CreateCast(CastOpcode, NewOp, I.getType());
+
+  // Preserve cast instruction flags
+  if (auto *NewCast = dyn_cast<CastInst>(Result)) {
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rhyadav wrote:

@dtcxzyw thanks for catching this, i've made the changes, all tests pass, @RKSimon pls have a look, happy to take on the rest of the changes in VectorCombine in a separate issue/patch.

https://github.com/llvm/llvm-project/pull/148350