[llvm] [AMDGPU] Remove unnecessary add instructions in ctlz.i8 (PR #77615)

[Leon Clark via llvm-commits]

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@@ -3062,6 +3071,26 @@ static bool isCttzOpc(unsigned Opc) {
   return Opc == ISD::CTTZ || Opc == ISD::CTTZ_ZERO_UNDEF;
 }
 
+SDValue AMDGPUTargetLowering::lowerCTLZResults(SDValue Op,
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PeddleSpam wrote:

I'm happy to change the name if there are no objections? I think "lowerX" was preferred for consistency with the other functions in `ReplaceNodeResults`.

https://github.com/llvm/llvm-project/pull/77615