[clang] [HLSL] Add matrix support to atan2 (PR #194984)

[Deric C. via cfe-commits]

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@@ -457,7 +457,7 @@ determine the correct quadrant.
 \param x The x-coordinate.
 }];
   let VaryingTypes = [HalfTy, FloatTy];
-  let VaryingMatDims = [];
+  let VaryingMatDims = AllMatDims;
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Icohedron wrote:

You can simply just remove the line because `HLSLTwoArgBuiltin` defines `let VaryingMatDims = AllMatDims;`.
The previous `let VaryingMatDims = [];` was just overriding it to disallow matrix types.
```suggestion
```

https://github.com/llvm/llvm-project/pull/194984