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

[Justin Bogner via cfe-commits]

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@@ -387,6 +387,23 @@ 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.
+
+_HLSL_BUILTIN_ALIAS(__builtin_hlsl_elementwise_asuint)
+uint asuint(float);
+_HLSL_BUILTIN_ALIAS(__builtin_hlsl_elementwise_asuint)
+uint2 asuint(float2);
+_HLSL_BUILTIN_ALIAS(__builtin_hlsl_elementwise_asuint)
+uint3 asuint(float3);
+_HLSL_BUILTIN_ALIAS(__builtin_hlsl_elementwise_asuint)
+uint4 asuint(float4);
+
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bogner wrote:

`IRBuilder::CreateBitCast` just returns the input if the type doesn't change, so the logic may already to the right thing.

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