[llvm] [AMDGPU] - Generate s_bitreplicate_b64_b32 (PR #69209)

[Matt Arsenault via llvm-commits]

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@@ -1470,6 +1472,18 @@ bool AMDGPUInstructionSelector::selectInverseBallot(MachineInstr &I) const {
   return true;
 }
 
+bool AMDGPUInstructionSelector::selectBitReplicate(MachineInstr &I) const {
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arsenm wrote:

This should be trivially selectable in tablegen 

https://github.com/llvm/llvm-project/pull/69209