[clang] [llvm] [HLSL] Implement the `reflect` HLSL function (PR #122992)

[Farzon Lotfi via llvm-commits]

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@@ -3030,6 +3039,8 @@ bool SPIRVInstructionSelector::selectIntrinsic(Register ResVReg,
     return selectExtInst(ResVReg, ResType, I, CL::fract, GL::Fract);
   case Intrinsic::spv_normalize:
     return selectExtInst(ResVReg, ResType, I, CL::normalize, GL::Normalize);
+  case Intrinsic::spv_reflect:
+    return selectExtInst(ResVReg, ResType, I, GL::Reflect);
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farzonl wrote:

go to this line: https://github.com/llvm/llvm-project/blob/6518b121f037717fd211c36659f7b25266424719/llvm/lib/Target/SPIRV/SPIRVInstructionSelector.cpp#L273

and remove the `[[maybe_unused]]`

https://github.com/llvm/llvm-project/pull/122992