[llvm] [CodeGen][MachineLICM] Use RegUnits in HoistRegionPostRA (PR #94608)

[Matt Arsenault via llvm-commits]

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@@ -583,24 +599,36 @@ void MachineLICMBase::HoistRegionPostRA(MachineLoop *CurLoop,
       continue;
 
     unsigned Def = Candidate.Def;
-    if (!PhysRegClobbers.test(Def) && !TermRegs.test(Def)) {
-      bool Safe = true;
-      MachineInstr *MI = Candidate.MI;
-      for (const MachineOperand &MO : MI->all_uses()) {
-        if (!MO.getReg())
-          continue;
-        Register Reg = MO.getReg();
-        if (PhysRegDefs.test(Reg) ||
-            PhysRegClobbers.test(Reg)) {
+    bool Safe = true;
+    for (MCRegUnitIterator RUI(Def, TRI); RUI.isValid(); ++RUI) {
+      if (RUClobbers.test(*RUI) || TermRUs.test(*RUI)) {
+        Safe = false;
+        break;
+      }
+    }
+
+    if (!Safe)
+      continue;
+
+    MachineInstr *MI = Candidate.MI;
+    for (const MachineOperand &MO : MI->all_uses()) {
+      if (!MO.getReg())
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arsenm wrote:

This misses regmasks for some reason, but it also missed them before? 

https://github.com/llvm/llvm-project/pull/94608