[clang] Adding `asuint` implementation to hlsl (PR #107292)

[Justin Bogner via cfe-commits]

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@@ -387,6 +387,65 @@ float3 asin(float3);
 _HLSL_BUILTIN_ALIAS(__builtin_elementwise_asin)
 float4 asin(float4);
 
+//===----------------------------------------------------------------------===//
+// asuint builtins
+//===----------------------------------------------------------------------===//
+
+/// \fn uint asuint(T Val)
+/// \brief Interprets the bit pattern of x as an unsigned integer.
+/// \param Val The input value.
+
+__attribute__((__always_inline__, __nodebug__)) static inline uint
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bogner wrote:

I kind of disagree with this, and I find the version with the macro pretty hard to follow.
1. Even if we have a macro to help with the attributes or something, it shouldn't be called "alias" - this isn't an alias at all (because of the static assert).
2. I don't really like that this single macro is defining multiple functions. The uses of `_HLSL_BUILTIN_ALIAS` decorate the definitions but each definition is written out clearly in source.

I could see some value in putting the `__attribute__((__always_inline__, __nodebug__))` bit in a macro so that it's easy to be consistent, but I don't think the function definitions themselves should be done this way.

https://github.com/llvm/llvm-project/pull/107292