[llvm] [LV] Add initial support for vectorizing literal struct return values (PR #109833)

[David Sherwood via llvm-commits]

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@@ -115,6 +115,13 @@ Type *VPTypeAnalysis::inferScalarTypeForRecipe(const VPWidenRecipe *R) {
   case Instruction::FNeg:
   case Instruction::Freeze:
     return inferScalarType(R->getOperand(0));
+  case Instruction::ExtractValue: {
+    assert(R->getNumOperands() == 2 && "expected single level extractvalue");
+    auto *StructTy = cast<StructType>(inferScalarType(R->getOperand(0)));
+    auto *CI = cast<ConstantInt>(R->getOperand(1)->getLiveInIRValue());
+    unsigned Idx = CI->getZExtValue();
+    return StructTy->getTypeAtIndex(Idx);
----------------
david-arm wrote:

Perhaps simply to just fold these two lines into:

```
  return StructTy->getTypeAtIndex(CI->getZExtValue());
```

https://github.com/llvm/llvm-project/pull/109833