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

[Justin Bogner via cfe-commits]

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@@ -0,0 +1,25 @@
+// RUN: %clang_cc1 -finclude-default-header -triple dxil-pc-shadermodel6.6-library %s -fnative-half-type -emit-llvm-only -disable-llvm-passes -verify
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bogner wrote:

The `-emit-llvm-only` and `-disable-llvm-passes` flags don't really do anything when combined with verify. We don't need them.
```suggestion
// RUN: %clang_cc1 -finclude-default-header -triple dxil-pc-shadermodel6.6-library %s -fnative-half-type -verify
```

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