[llvm-branch-commits] [llvm] AMDGPU/GlobalISel: Temporal divergence lowering (non i1) (PR #124298)

[via llvm-branch-commits]

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@@ -188,6 +190,35 @@ void DivergenceLoweringHelper::constrainAsLaneMask(Incoming &In) {
   In.Reg = Copy.getReg(0);
 }
 
+void replaceUsesOfRegInInstWith(Register Reg, MachineInstr *Inst,
+                                Register NewReg) {
+  for (MachineOperand &Op : Inst->operands()) {
+    if (Op.isReg() && Op.getReg() == Reg)
+      Op.setReg(NewReg);
+  }
+}
+
+bool DivergenceLoweringHelper::lowerTemporalDivergence() {
+  AMDGPU::IntrinsicLaneMaskAnalyzer ILMA(*MF);
+
+  for (auto [Inst, UseInst, _] : MUI->getTemporalDivergenceList()) {
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ruiling wrote:

I am not sure if it is ok to assume only the first `def` can be temporal divergent. Maybe holds a map from the `Register` to a array of temporal divergence users?

https://github.com/llvm/llvm-project/pull/124298