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

[via cfe-commits]

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@@ -0,0 +1,18 @@
+// RUN: %clang_cc1 -finclude-default-header -triple dxil-pc-shadermodel6.6-library %s -fnative-half-type -emit-llvm-only -disable-llvm-passes -verify -verify-ignore-unexpected
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joaosaffran wrote:

I am seeing some issues when testing without it, for example:

```
error: 'expected-error' diagnostics seen but not expected
```

The error messages are really verbose. What is the best approach here: i) add the verbose lines?; ii) ignore the unexpected and check only one of the errors?

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