[clang] [llvm] [HLSL] Add wave prefix count bits function (PR #178059)

[Tex Riddell via cfe-commits]

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@@ -1124,6 +1127,25 @@ def WaveActiveOp : DXILOp<119, waveActiveOp> {
   let attributes = [Attributes<DXIL1_0, []>];
 }
 
+def WavePrefixOp : DXILOp<121, wavePrefixOp> {
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tex3d wrote:

I think we should keep the BitCount DXIL operation defined separately from the more general WavePrefixOp DXIL operation that takes the WaveOpKind and SignedOpKind enumerations as arguments.

https://github.com/llvm/llvm-project/pull/178059