C++ (Cpp) MachineOperand::setIsRenamable Examples

Example #1

File: RegAllocFast.cpp Project: jvesely/llvm

/// Changes operand OpNum in MI the refer the PhysReg, considering subregs. This
/// may invalidate any operand pointers.  Return true if the operand kills its
/// register.
bool RegAllocFast::setPhysReg(MachineInstr &MI, MachineOperand &MO,
                              MCPhysReg PhysReg) {
  bool Dead = MO.isDead();
  if (!MO.getSubReg()) {
    MO.setReg(PhysReg);
    MO.setIsRenamable(true);
    return MO.isKill() || Dead;
  }

  // Handle subregister index.
  MO.setReg(PhysReg ? TRI->getSubReg(PhysReg, MO.getSubReg()) : 0);
  MO.setIsRenamable(true);
  MO.setSubReg(0);

  // A kill flag implies killing the full register. Add corresponding super
  // register kill.
  if (MO.isKill()) {
    MI.addRegisterKilled(PhysReg, TRI, true);
    return true;
  }

  // A <def,read-undef> of a sub-register requires an implicit def of the full
  // register.
  if (MO.isDef() && MO.isUndef())
    MI.addRegisterDefined(PhysReg, TRI);

  return Dead;
}

Example #2

File: RegAllocFast.cpp Project: jvesely/llvm

void RegAllocFast::allocVirtRegUndef(MachineOperand &MO) {
  assert(MO.isUndef() && "expected undef use");
  unsigned VirtReg = MO.getReg();
  assert(TargetRegisterInfo::isVirtualRegister(VirtReg) && "Expected virtreg");

  LiveRegMap::const_iterator LRI = findLiveVirtReg(VirtReg);
  MCPhysReg PhysReg;
  if (LRI != LiveVirtRegs.end() && LRI->PhysReg) {
    PhysReg = LRI->PhysReg;
  } else {
    const TargetRegisterClass &RC = *MRI->getRegClass(VirtReg);
    ArrayRef<MCPhysReg> AllocationOrder = RegClassInfo.getOrder(&RC);
    assert(!AllocationOrder.empty() && "Allocation order must not be empty");
    PhysReg = AllocationOrder[0];
  }

  unsigned SubRegIdx = MO.getSubReg();
  if (SubRegIdx != 0) {
    PhysReg = TRI->getSubReg(PhysReg, SubRegIdx);
    MO.setSubReg(0);
  }
  MO.setReg(PhysReg);
  MO.setIsRenamable(true);
}