[llvm] [PowerPC] Deprecate uses of ISD::ADDC/ISD::ADDE/ISD::SUBC/ISD::SUBE (PR #133155)

[Maryam Moghadas via llvm-commits]

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@@ -338,3 +338,25 @@ void llvm::computeAndAddLiveIns(LivePhysRegs &LiveRegs,
   computeLiveIns(LiveRegs, MBB);
   addLiveIns(MBB, LiveRegs);
 }
+
+bool llvm::isPhysRegLiveAfter(Register Reg, MachineBasicBlock::iterator MBI) {
+  assert(Reg.isPhysical() && "Apply to physical register only");
+
+  MachineBasicBlock *MBB = MBI->getParent();
+  // Scan forward through BB for a use/def of Reg
+  for (const MachineInstr &MI : llvm::make_range(std::next(MBI), MBB->end())) {
+    if (MI.readsRegister(Reg, /*TRI=*/nullptr))
+      return true;
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maryammo wrote:

Why does it return true if a Reg is being read here but then being redefined later in this MBB?

https://github.com/llvm/llvm-project/pull/133155