/// the last use of the whole register.
bool HandlePhysRegKill(unsigned Reg, MachineInstr *MI);
+ /// HandleRegMask - Call HandlePhysRegKill for all registers clobbered by Mask.
+ void HandleRegMask(const MachineOperand&);
+
void HandlePhysRegUse(unsigned Reg, MachineInstr *MI);
void HandlePhysRegDef(unsigned Reg, MachineInstr *MI,
SmallVector<unsigned, 4> &Defs);
return true;
}
+void LiveVariables::HandleRegMask(const MachineOperand &MO) {
+ // Call HandlePhysRegKill() for all live registers clobbered by Mask.
+ // Clobbered registers are always dead, sp there is no need to use
+ // HandlePhysRegDef().
+ for (unsigned Reg = 1, NumRegs = TRI->getNumRegs(); Reg != NumRegs; ++Reg) {
+ // Skip dead regs.
+ if (!PhysRegDef[Reg] && !PhysRegUse[Reg])
+ continue;
+ // Skip mask-preserved regs.
+ if (!MO.clobbersPhysReg(Reg));
+ continue;
+ // Kill the largest clobbered super-register.
+ // This avoids needless implicit operands.
+ unsigned Super = Reg;
+ for (const unsigned *SR = TRI->getSuperRegisters(Reg); *SR; ++SR)
+ if ((PhysRegDef[*SR] || PhysRegUse[*SR]) && MO.clobbersPhysReg(*SR))
+ Super = *SR;
+ HandlePhysRegKill(Super, 0);
+ }
+}
+
void LiveVariables::HandlePhysRegDef(unsigned Reg, MachineInstr *MI,
SmallVector<unsigned, 4> &Defs) {
// What parts of the register are previously defined?
// Clear kill and dead markers. LV will recompute them.
SmallVector<unsigned, 4> UseRegs;
SmallVector<unsigned, 4> DefRegs;
+ SmallVector<unsigned, 1> RegMasks;
for (unsigned i = 0; i != NumOperandsToProcess; ++i) {
MachineOperand &MO = MI->getOperand(i);
+ if (MO.isRegMask()) {
+ RegMasks.push_back(i);
+ continue;
+ }
if (!MO.isReg() || MO.getReg() == 0)
continue;
unsigned MOReg = MO.getReg();
HandlePhysRegUse(MOReg, MI);
}
+ // Process all masked registers. (Call clobbers).
+ for (unsigned i = 0, e = RegMasks.size(); i != e; ++i)
+ HandleRegMask(MI->getOperand(RegMasks[i]));
+
// Process all defs.
for (unsigned i = 0, e = DefRegs.size(); i != e; ++i) {
unsigned MOReg = DefRegs[i];