[clang] [llvm] [HLSL][DXIL][SPRIV] Added WaveActiveProduct intrinsic #164385 (PR #165109)

[Sietze Riemersma via cfe-commits]

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@@ -2766,6 +2528,32 @@ bool SPIRVInstructionSelector::selectWaveReduceSum(Register ResVReg,
       .addUse(I.getOperand(2).getReg());
 }
 
+bool SPIRVInstructionSelector::selectWaveReduceProduct(Register ResVReg,
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KungFuDonkey wrote:

`selectWaveOpInst` does not take into account the 'reduce' factor of the instruction and does not support multiple instruction types (E.G. float and integer type). I see that WaveActiveSum now has a selectWaveReduce function. I will start using that instead. But I agree, this is tedious. The only way I see how we would implement a single function that could handle all cases would be with a macro.

https://github.com/llvm/llvm-project/pull/165109