[llvm] [NVPTX] Generalize and extend upsizing when lowering 8/16-bit-element vector loads/stores (PR #119622)

[Artem Belevich via llvm-commits]

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@@ -3185,10 +3205,15 @@ NVPTXTargetLowering::LowerSTOREVector(SDValue Op, SelectionDAG &DAG) const {
     case MVT::v4f16:
     case MVT::v4bf16:
     case MVT::v4f32:
-    case MVT::v8f16: // <4 x f16x2>
+      // This is a "native" vector type
+      break;
+    case MVT::v8i8:   // <2 x i8x4>
+    case MVT::v8f16:  // <4 x f16x2>
     case MVT::v8bf16: // <4 x bf16x2>
     case MVT::v8i16:  // <4 x i16x2>
-      // This is a "native" vector type
+    case MVT::v16i8:  // <4 x i8x4>
+      // This can be upsized into a "native" vector type
+      UpsizeElementTypes = true;
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Artem-B wrote:

This whole switch should probably be folded into `GetUpsizedNumEltsAndEltVT` and `UpsizeElementTypes` returned as an additional `bool`.
Then we could just use `auto [Upsize, NumElts, EltVT] = GetUpsizedNumEltsAndEltVT(ValVT.getVectorNumElements(), ValVT.getVectorElementType())`



https://github.com/llvm/llvm-project/pull/119622