[clang] [llvm] [HLSL][DirectX][SPIRV] Implement the `fma` API (PR #185304)

[Deric C. via llvm-commits]

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@@ -106,6 +106,15 @@ static bool checkWaveOps(Intrinsic::ID IID) {
   }
 }
 
+static bool checkFmaOps(Intrinsic::ID IID) {
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Icohedron wrote:

I would change the name of this function to `checkDoubleExtensionOps` since this will be checking for more than just `fma` in the future.
https://github.com/microsoft/DirectXShaderCompiler/blob/054e0f5076cf2ab6ff48442adab9c38e95824629/lib/DXIL/DxilShaderFlags.cpp#L557-L567

https://github.com/llvm/llvm-project/pull/185304