[clang] [HLSL] Implement output parameter (PR #101083)

[John McCall via cfe-commits]

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@@ -7061,6 +7061,67 @@ class ArraySectionExpr : public Expr {
   void setRBracketLoc(SourceLocation L) { RBracketLoc = L; }
 };
 
+/// This class represents temporary values used to represent inout and out
+/// arguments in HLSL. From the callee perspective these parameters are more or
+/// less __restrict__ T&. They are guaranteed to not alias any memory. inout
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rjmccall wrote:

```suggestion
/// less `T & restrict`. They are guaranteed to not alias any memory. inout
```

https://github.com/llvm/llvm-project/pull/101083