void setUnused(unsigned Reg) { RegStates.set(Reg); }
void setUnused(BitVector Regs) { RegStates |= Regs; }
+ /// FindUnusedReg - Find a unused register of the specified register class
+ /// from the specified set of registers. It return 0 is none is found.
+ unsigned FindUnusedReg(const TargetRegisterClass *RegClass,
+ const BitVector &Candidates) const;
+
/// FindUnusedReg - Find a unused register of the specified register class.
/// Exclude callee saved registers if directed. It return 0 is none is found.
unsigned FindUnusedReg(const TargetRegisterClass *RegClass,
Mask.set(*I);
}
+unsigned RegScavenger::FindUnusedReg(const TargetRegisterClass *RegClass,
+ const BitVector &Candidates) const {
+ // Mask off the registers which are not in the TargetRegisterClass.
+ BitVector RegStatesCopy(NumPhysRegs, false);
+ CreateRegClassMask(RegClass, RegStatesCopy);
+ RegStatesCopy &= RegStates;
+
+ // Restrict the search to candidates.
+ RegStatesCopy &= Candidates;
+
+ // Returns the first unused (bit is set) register, or 0 is none is found.
+ int Reg = RegStatesCopy.find_first();
+ return (Reg == -1) ? 0 : Reg;
+}
+
unsigned RegScavenger::FindUnusedReg(const TargetRegisterClass *RegClass,
bool ExCalleeSaved) const {
// Mask off the registers which are not in the TargetRegisterClass.