[clang] [llvm] [DirectX] Add DirectXTargetCodeGenInfo (PR #104856)

[Justin Bogner via cfe-commits]

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@@ -879,6 +879,10 @@ static TargetTypeInfo getTargetTypeInfo(const TargetExtType *Ty) {
         ScalableVectorType::get(Type::getInt8Ty(C), TotalNumElts));
   }
 
+  // DirectX intangible types
+  if (Name.starts_with("dx."))
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bogner wrote:

Yeah, it's definitely kind of annoying to have this all be string based, but that's what it is.

The "intangible types" comment is maybe misleading here, but this isn't actually burning all of the `dx.` prefixed names. See the `spirv` case, where it further specializes based on the rest of the name.

https://github.com/llvm/llvm-project/pull/104856