[clang] [HLSL] Collect explicit resource binding information (PR #111203)

[Helena Kotas via cfe-commits]

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@@ -58,31 +56,82 @@ static RegisterType getRegisterType(ResourceClass RC) {
   llvm_unreachable("unexpected ResourceClass value");
 }
 
-static RegisterType getRegisterType(StringRef Slot) {
+// Converts the first letter of string Slot to RegisterType.
+// Returns false if the letter does not correspond to a valid register type.
+static bool convertToRegisterType(StringRef Slot, RegisterType *RT) {
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hekota wrote:

I've considered it, but since we `convertToRegisterType` does not create an error string or code that we should report I just kept it simple.

https://github.com/llvm/llvm-project/pull/111203