[llvm] [DirectX] Add support for Raw Buffer Loads and Stores for scalars and vectors of doubles and i64s in SM6.2 and earlier (PR #146627)

[Farzon Lotfi via llvm-commits]

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@@ -71,12 +71,23 @@ static bool isIntrinsicExpansion(Function &F) {
   case Intrinsic::vector_reduce_add:
   case Intrinsic::vector_reduce_fadd:
     return true;
+  case Intrinsic::dx_resource_load_rawbuffer:
+    if (F.getParent()->getTargetTriple().getDXILVersion() > VersionTuple(1, 2))
+      return false;
+    // fallthrough to check if double or i64
+    LLVM_FALLTHROUGH;
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farzonl wrote:

Do we need to do a fall through, couldn't this just be return true?

https://github.com/llvm/llvm-project/pull/146627