[clang] [HLSL] Default and Relaxed Availability Diagnostics (PR #92704)

[Damyan Pepper via cfe-commits]

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@@ -350,7 +350,7 @@ class DiagnoseHLSLAvailability
     static_assert(HLSLShaderAttr::ShaderTypeMaxValue < 31,
                   "ShaderType is too big for this bitmap");
     assert((((unsigned)1) << (unsigned)ShaderType) != 0 &&
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damyanp wrote:

I wonder at this point if all we really need here is:

```
static_assert(sizeof(unsigned) >= 4); // if we want to be really paranoid
assert((unsigned)ShaderType < 31);
```


https://github.com/llvm/llvm-project/pull/92704