[clang] [llvm] [HLSL][DXIL][SPIRV] WavePrefixSum intrinsic support (PR #167946)

[via llvm-commits]

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@@ -276,6 +276,29 @@ llvm::Triple::ArchType CGHLSLRuntime::getArch() {
   return CGM.getTarget().getTriple().getArch();
 }
 
+llvm::Intrinsic::ID
+CGHLSLRuntime::getUnsignedIntrinsicVariant(llvm::Intrinsic::ID IID) {
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kcloudy0717 wrote:

My reasoning for this approach was that certain DXIL intrinsics doesn't have 1:1 mapping to SPIRV intrinsics. `WaveActiveSum` and `WavePrefixSum` (this PR) have both `usum` and `sum` DXIL intrinsics but in SPIRV is just `sum`. I was trying to come up with a proper solution that could fix all the static functions to get the intrinsics in `CGHLSLBuiltins.cpp`

https://github.com/llvm/llvm-project/pull/167946