[llvm-branch-commits] [llvm] [AMDGPU] Extending wave reduction intrinsics for `i64` types - 2 (PR #151309)

[Matt Arsenault via llvm-branch-commits]

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@@ -5212,6 +5217,74 @@ static MachineBasicBlock *lowerWaveReduce(MachineInstr &MI,
             .addReg(NewAccumulator->getOperand(0).getReg());
         break;
       }
+      case AMDGPU::S_ADD_U64_PSEUDO:
+      case AMDGPU::S_SUB_U64_PSEUDO: {
+        Register DestSub0 = MRI.createVirtualRegister(&AMDGPU::SReg_32RegClass);
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arsenm wrote:

My point was don't duplicate code. Call a common helper function to expand the 64-bit add 

https://github.com/llvm/llvm-project/pull/151309