unsigned LastNewReg,
const TargetRegisterClass *);
void StartBlockForKills(MachineBasicBlock *BB);
+
+ // ToggleKillFlag - Toggle a register operand kill flag. Other
+ // adjustments may be made to the instruction if necessary. Return
+ // true if the operand has been deleted, false if not.
+ bool ToggleKillFlag(MachineInstr *MI, MachineOperand &MO);
};
}
}
}
+bool SchedulePostRATDList::ToggleKillFlag(MachineInstr *MI,
+ MachineOperand &MO) {
+ // Setting kill flag...
+ if (!MO.isKill()) {
+ MO.setIsKill(true);
+ return false;
+ }
+
+ // If MO itself is live, clear the kill flag...
+ if (KillIndices[MO.getReg()] != ~0u) {
+ MO.setIsKill(false);
+ return false;
+ }
+
+ // If any subreg of MO is live, then create an imp-def for that
+ // subreg and keep MO marked as killed.
+ bool AllDead = true;
+ const unsigned SuperReg = MO.getReg();
+ for (const unsigned *Subreg = TRI->getSubRegisters(SuperReg);
+ *Subreg; ++Subreg) {
+ if (KillIndices[*Subreg] != ~0u) {
+ MI->addOperand(MachineOperand::CreateReg(*Subreg,
+ true /*IsDef*/,
+ true /*IsImp*/,
+ false /*IsKill*/,
+ false /*IsDead*/));
+ AllDead = false;
+ }
+ }
+
+ MO.setIsKill(AllDead);
+ return false;
+}
+
/// FixupKills - Fix the register kill flags, they may have been made
/// incorrect by instruction reordering.
///
}
}
- // Examine all used registers and set kill flag. When a register
- // is used multiple times we only set the kill flag on the first
- // use.
+ // Examine all used registers and set/clear kill flag. When a
+ // register is used multiple times we only set the kill flag on
+ // the first use.
killedRegs.clear();
for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
MachineOperand &MO = MI->getOperand(i);
}
if (MO.isKill() != kill) {
- MO.setIsKill(kill);
- DEBUG(errs() << "Fixed " << MO << " in ");
+ bool removed = ToggleKillFlag(MI, MO);
+ if (removed) {
+ DEBUG(errs() << "Fixed <removed> in ");
+ } else {
+ DEBUG(errs() << "Fixed " << MO << " in ");
+ }
DEBUG(MI->dump());
}