[llvm] [VPlan] Unroll VPReplicateRecipe by VF. (PR #142433)

[via llvm-commits]

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@@ -604,6 +607,33 @@ Value *VPInstruction::generate(VPTransformState &State) {
     return Builder.CreateVectorSplat(
         State.VF, State.get(getOperand(0), /*IsScalar*/ true), "broadcast");
   }
+  case VPInstruction::BuildVector: {
+    auto *ScalarTy = State.TypeAnalysis.inferScalarType(getOperand(0));
+    Value *Res = PoisonValue::get(
+        toVectorizedTy(ScalarTy, ElementCount::getFixed(getNumOperands())));
+    for (const auto &[Idx, Op] : enumerate(operands()))
+      Res = State.Builder.CreateInsertElement(Res, State.get(Op, true),
+                                              State.Builder.getInt32(Idx));
+    return Res;
+  }
+  case VPInstruction::BuildStructVector: {
+    // For struct types, we need to build a new 'wide' struct type, where each
+    // element is widened.
+    auto *STy =
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ayalz wrote:

```suggestion
    auto *StructTy =
```

https://github.com/llvm/llvm-project/pull/142433