[llvm] AMDGPU/GlobalISel: RegBankLegalize rules for s_bitreplicate (PR #189138)

[Matt Arsenault via llvm-commits]

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@@ -924,6 +890,80 @@ bool RegBankLegalizeHelper::lowerSplitBitCount64To32(MachineInstr &MI) {
   return true;
 }
 
+bool RegBankLegalizeHelper::lowerBitReplicateToVALU(MachineInstr &MI) {
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arsenm wrote:

We need execution tests for this 

https://github.com/llvm/llvm-project/pull/189138