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

[Drew Kersnar 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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dakersnar wrote:

I implemented the above std::tie solution but let me know if you still think there is a better way. I'm still hesitant to fold the entire switch into the helper function because the switch is responsible for exiting early from `ReplaceLoadVector`/`LowerSTOREVector` and I don't think there is a clean way to do it, but if I'm missing something I'm happy to tweak it.

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