[clang] [llvm] [HLSL] Implement ddx/ddy_coarse intrinsics (PR #164831)

[Farzon Lotfi via llvm-commits]

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@@ -0,0 +1,41 @@
+; RUN: opt -S  -scalarizer -dxil-op-lower -mtriple=dxil-pc-shadermodel6.3-library %s | FileCheck %s
+
+; Make sure dxil operation function calls for fwidth are generated for half/float and matching vectors
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farzonl wrote:

```suggestion
; Make sure dxil operation function calls for ddx_coarse are generated for half/float and matching vectors
```

https://github.com/llvm/llvm-project/pull/164831