virtual ~MRegisterInfo();
public:
- /// getRegScavenger - Returns pointer to an instance of register scavenger it
- /// the specific target is making use of one.
- virtual RegScavenger *getRegScavenger() const {
- return NULL;
- }
-
enum { // Define some target independent constants
/// NoRegister - This physical register is not a real target register. It
/// is useful as a sentinal.
return false;
}
+ /// requiresRegisterScavenging - returns true if the target requires (and
+ /// can make use of) the register scavenger.
+ virtual bool requiresRegisterScavenging() const {
+ return false;
+ }
+
/// hasFP - Return true if the specified function should have a dedicated frame
/// pointer register. For most targets this is true only if the function has
/// variable sized allocas or if frame pointer elimination is disabled.
/// finished product. The return value is the number of instructions
/// added to (negative if removed from) the basic block.
///
- virtual void eliminateFrameIndex(MachineBasicBlock::iterator MI) const = 0;
+ virtual void eliminateFrameIndex(MachineBasicBlock::iterator MI,
+ RegScavenger *RS = NULL) const = 0;
/// emitProlog/emitEpilog - These methods insert prolog and epilog code into
/// the function. The return value is the number of instructions
const TargetMachine &TM = Fn.getTarget();
assert(TM.getRegisterInfo() && "TM::getRegisterInfo() must be implemented!");
const MRegisterInfo &MRI = *TM.getRegisterInfo();
- RegScavenger *RS = MRI.getRegScavenger();
+ RegScavenger *RS = MRI.requiresRegisterScavenging() ? new RegScavenger():NULL;
for (MachineFunction::iterator BB = Fn.begin(), E = Fn.end(); BB != E; ++BB) {
if (RS) RS->reset(BB);
if (I->getOperand(i).isFrameIndex()) {
// If this instruction has a FrameIndex operand, we need to use that
// target machine register info object to eliminate it.
- MRI.eliminateFrameIndex(I);
+ MRI.eliminateFrameIndex(I, RS);
break;
}
// Update register states.