[llvm] [LLVM] Make use of s_flbit_i32_b64 and s_ff1_i32_b64 (PR #75158)

[Acim Maravic via llvm-commits]

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@@ -7834,6 +7843,56 @@ void SIInstrInfo::splitScalar64BitBFE(SIInstrWorklist &Worklist,
   addUsersToMoveToVALUWorklist(ResultReg, MRI, Worklist);
 }
 
+void SIInstrInfo::splitScalar64BitCountOp(SIInstrWorklist &Worklist,
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Acim-Maravic wrote:

I added a comment. The final add with 64 was because I thought that when input is all zeroes it should return 64..., I changed that now. I have added tests, I hope that is okay now.

https://github.com/llvm/llvm-project/pull/75158