[llvm] [DXIL] Add DXIL version-specific TableGen specification and implementation of DXIL Ops (PR #97593)

[S. Bharadwaj Yadavalli via llvm-commits]

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@@ -282,40 +420,18 @@ Type *DXILOpBuilder::getOverloadTy(dxil::OpCode OpCode, FunctionType *FT) {
   // If DXIL Op has no overload parameter, just return the
   // precise return type specified.
   if (Prop->OverloadParamIndex < 0) {
-    auto &Ctx = FT->getContext();
-    switch (Prop->OverloadTys) {
-    case OverloadKind::VOID:
-      return Type::getVoidTy(Ctx);
-    case OverloadKind::HALF:
-      return Type::getHalfTy(Ctx);
-    case OverloadKind::FLOAT:
-      return Type::getFloatTy(Ctx);
-    case OverloadKind::DOUBLE:
-      return Type::getDoubleTy(Ctx);
-    case OverloadKind::I1:
-      return Type::getInt1Ty(Ctx);
-    case OverloadKind::I8:
-      return Type::getInt8Ty(Ctx);
-    case OverloadKind::I16:
-      return Type::getInt16Ty(Ctx);
-    case OverloadKind::I32:
-      return Type::getInt32Ty(Ctx);
-    case OverloadKind::I64:
-      return Type::getInt64Ty(Ctx);
-    default:
-      llvm_unreachable("invalid overload type");
-      return nullptr;
-    }
+    return FT->getReturnType();
   }
 
-  // Prop->OverloadParamIndex is 0, overload type is FT->getReturnType().
+  // Consider FT->getReturnType() as default overload type, unless
+  // Prop->OverloadParamIndex != 0.
   Type *OverloadType = FT->getReturnType();
   if (Prop->OverloadParamIndex != 0) {
     // Skip Return Type.
     OverloadType = FT->getParamType(Prop->OverloadParamIndex - 1);
   }
 
-  auto ParamKinds = getOpCodeParameterKind(*Prop);
+  const auto *ParamKinds = getOpCodeParameterKind(*Prop);
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bharadwajy wrote:

> I don't know what this type is from the context here which makes me think it shouldn't be `auto` (https://llvm.org/docs/CodingStandards.html#use-auto-type-deduction-to-make-code-more-readable).

Changed `auto` to `ParamKind`

https://github.com/llvm/llvm-project/pull/97593