[llvm] [NVPTX] Vectorize loads when lowering of byval calls, misc. cleanup (PR #151070)

[Alex MacLean via llvm-commits]

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@@ -382,6 +382,51 @@ static void ComputePTXValueVTs(const TargetLowering &TLI, const DataLayout &DL,
   }
 }
 
+static EVT getVectorizedVT(EVT VT, unsigned N, LLVMContext &C) {
+  if (N == 1)
+    return VT;
+
+  const unsigned PackingAmt = VT.isVector() ? VT.getVectorNumElements() : 1;
+  return EVT::getVectorVT(C, VT.getScalarType(), N * PackingAmt);
+}
+
+static SDValue getExtractVectorizedValue(SDValue V, unsigned I, EVT VT,
+                                         const SDLoc &dl, SelectionDAG &DAG) {
+  if (V.getValueType() == VT) {
+    assert(I == 0 && "Index must be 0 for scalar value");
+    return V;
+  }
+
+  if (!VT.isVector())
+    return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, VT, V,
+                       DAG.getVectorIdxConstant(I, dl));
+
+  return DAG.getNode(
+      ISD::EXTRACT_SUBVECTOR, dl, VT, V,
+      DAG.getVectorIdxConstant(I * VT.getVectorNumElements(), dl));
+}
+
+template <typename T>
+static inline SDValue getBuildVectorizedValue(T GetElement, unsigned N,
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AlexMaclean wrote:

Moved.

https://github.com/llvm/llvm-project/pull/151070