[llvm] [VPlan] Fix issues around scalar-cast VPInstructions (NFC) (PR #195629)

[Florian Hahn via llvm-commits]

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@@ -1614,6 +1613,13 @@ void VPInstructionWithType::execute(VPTransformState &State) {
   }
 }
 
+InstructionCost VPInstructionWithType::computeCost(ElementCount VF,
+                                                   VPCostContext &Ctx) const {
+  if (!getUnderlyingValue())
+    return 0;
+  return getCostForRecipeWithOpcode(getOpcode(), VF, Ctx);
+}
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fhahn wrote:

Could we do those independently of clean up/removal of isScalarCast? The other changes are potentially functional, but currently untested?

https://github.com/llvm/llvm-project/pull/195629