[llvm] [AMDGPU] Refine operand iterators in the SIInsertWaitcnts. NFCI. (PR #108884)

[Stanislav Mekhanoshin via llvm-commits]

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@@ -2357,41 +2323,43 @@ bool SIInsertWaitcnts::shouldFlushVmCnt(MachineLoop *ML,
         if (MI.mayStore())
           HasVMemStore = true;
       }
-      for (unsigned I = 0; I < MI.getNumOperands(); I++) {
-        MachineOperand &Op = MI.getOperand(I);
+      for (const MachineOperand &Op : MI.uses()) {
         if (!Op.isReg() || !TRI->isVectorRegister(*MRI, Op.getReg()))
           continue;
-        RegInterval Interval = Brackets.getRegInterval(&MI, MRI, TRI, I);
+        RegInterval Interval = Brackets.getRegInterval(&MI, MRI, TRI, Op);
         // Vgpr use
-        if (Op.isUse()) {
-          for (int RegNo = Interval.first; RegNo < Interval.second; ++RegNo) {
-            // If we find a register that is loaded inside the loop, 1. and 2.
-            // are invalidated and we can exit.
-            if (VgprDef.contains(RegNo))
-              return false;
-            VgprUse.insert(RegNo);
-            // If at least one of Op's registers is in the score brackets, the
-            // value is likely loaded outside of the loop.
-            if (Brackets.getRegScore(RegNo, LOAD_CNT) >
-                    Brackets.getScoreLB(LOAD_CNT) ||
-                Brackets.getRegScore(RegNo, SAMPLE_CNT) >
-                    Brackets.getScoreLB(SAMPLE_CNT) ||
-                Brackets.getRegScore(RegNo, BVH_CNT) >
-                    Brackets.getScoreLB(BVH_CNT)) {
-              UsesVgprLoadedOutside = true;
-              break;
-            }
+        for (int RegNo = Interval.first; RegNo < Interval.second; ++RegNo) {
+          // If we find a register that is loaded inside the loop, 1. and 2.
+          // are invalidated and we can exit.
+          if (VgprDef.contains(RegNo))
+            return false;
+          VgprUse.insert(RegNo);
+          // If at least one of Op's registers is in the score brackets, the
+          // value is likely loaded outside of the loop.
+          if (Brackets.getRegScore(RegNo, LOAD_CNT) >
+                  Brackets.getScoreLB(LOAD_CNT) ||
+              Brackets.getRegScore(RegNo, SAMPLE_CNT) >
+                  Brackets.getScoreLB(SAMPLE_CNT) ||
+              Brackets.getRegScore(RegNo, BVH_CNT) >
+                  Brackets.getScoreLB(BVH_CNT)) {
+            UsesVgprLoadedOutside = true;
+            break;
           }
         }
-        // VMem load vgpr def
-        else if (isVMEMOrFlatVMEM(MI) && MI.mayLoad() && Op.isDef())
+      }
+
+      // VMem load vgpr def
+      if (isVMEMOrFlatVMEM(MI) && MI.mayLoad()) {
+        for (const MachineOperand &Op : MI.defs()) {
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rampitec wrote:

Again, this cannot happen, but can be a separate change. Done.

https://github.com/llvm/llvm-project/pull/108884