#include "llvm/Support/raw_ostream.h"
using namespace llvm;
+// FIXME: This cmd line option conditionalizes the new register scavenging
+// implemenation in PEI. Remove the option when scavenging works well enough
+// to be the default.
+extern cl::opt<bool> FrameIndexVirtualScavenging;
+
Thumb1RegisterInfo::Thumb1RegisterInfo(const ARMBaseInstrInfo &tii,
const ARMSubtarget &sti)
: ARMBaseRegisterInfo(tii, sti) {
bool
Thumb1RegisterInfo::requiresRegisterScavenging(const MachineFunction &MF) const {
- return true;
-}
-
-bool
-Thumb1RegisterInfo::requiresFrameIndexScavenging(const MachineFunction &MF)
- const {
- return true;
+ return FrameIndexVirtualScavenging;
}
bool Thumb1RegisterInfo::hasReservedCallFrame(MachineFunction &MF) const {
unsigned LdReg = DestReg;
if (DestReg == ARM::SP) {
assert(BaseReg == ARM::SP && "Unexpected!");
- LdReg = MF.getRegInfo().createVirtualRegister(ARM::tGPRRegisterClass);
+ if (FrameIndexVirtualScavenging) {
+ LdReg = MF.getRegInfo().createVirtualRegister(ARM::tGPRRegisterClass);
+ } else {
+ LdReg = ARM::R3;
+ BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVtgpr2gpr), ARM::R12)
+ .addReg(ARM::R3, RegState::Kill);
+ }
}
if (NumBytes <= 255 && NumBytes >= 0)
else
MIB.addReg(LdReg).addReg(BaseReg, RegState::Kill);
AddDefaultPred(MIB);
+
+ if (!FrameIndexVirtualScavenging && DestReg == ARM::SP)
+ BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVgpr2tgpr), ARM::R3)
+ .addReg(ARM::R12, RegState::Kill);
}
/// calcNumMI - Returns the number of instructions required to materialize
else // tLDR has an extra register operand.
MI.addOperand(MachineOperand::CreateReg(0, false));
} else if (Desc.mayStore()) {
+ if (FrameIndexVirtualScavenging) {
VReg = MF.getRegInfo().createVirtualRegister(ARM::tGPRRegisterClass);
assert (Value && "Frame index virtual allocated, but Value arg is NULL!");
*Value = Offset;
MI.addOperand(MachineOperand::CreateReg(FrameReg, false));
else // tSTR has an extra register operand.
MI.addOperand(MachineOperand::CreateReg(0, false));
+ } else {
+ // FIXME! This is horrific!!! We need register scavenging.
+ // Our temporary workaround has marked r3 unavailable. Of course, r3 is
+ // also a ABI register so it's possible that is is the register that is
+ // being storing here. If that's the case, we do the following:
+ // r12 = r2
+ // Use r2 to materialize sp + offset
+ // str r3, r2
+ // r2 = r12
+ unsigned ValReg = MI.getOperand(0).getReg();
+ unsigned TmpReg = ARM::R3;
+ bool UseRR = false;
+ if (ValReg == ARM::R3) {
+ BuildMI(MBB, II, dl, TII.get(ARM::tMOVtgpr2gpr), ARM::R12)
+ .addReg(ARM::R2, RegState::Kill);
+ TmpReg = ARM::R2;
+ }
+ if (TmpReg == ARM::R3 && AFI->isR3LiveIn())
+ BuildMI(MBB, II, dl, TII.get(ARM::tMOVtgpr2gpr), ARM::R12)
+ .addReg(ARM::R3, RegState::Kill);
+ if (Opcode == ARM::tSpill) {
+ if (FrameReg == ARM::SP)
+ emitThumbRegPlusImmInReg(MBB, II, TmpReg, FrameReg,
+ Offset, false, TII, *this, dl);
+ else {
+ emitLoadConstPool(MBB, II, dl, TmpReg, 0, Offset);
+ UseRR = true;
+ }
+ } else
+ emitThumbRegPlusImmediate(MBB, II, TmpReg, FrameReg, Offset, TII,
+ *this, dl);
+ MI.setDesc(TII.get(ARM::tSTR));
+ MI.getOperand(i).ChangeToRegister(TmpReg, false, false, true);
+ if (UseRR) // Use [reg, reg] addrmode.
+ MI.addOperand(MachineOperand::CreateReg(FrameReg, false));
+ else // tSTR has an extra register operand.
+ MI.addOperand(MachineOperand::CreateReg(0, false));
+
+ MachineBasicBlock::iterator NII = next(II);
+ if (ValReg == ARM::R3)
+ BuildMI(MBB, NII, dl, TII.get(ARM::tMOVgpr2tgpr), ARM::R2)
+ .addReg(ARM::R12, RegState::Kill);
+ if (TmpReg == ARM::R3 && AFI->isR3LiveIn())
+ BuildMI(MBB, NII, dl, TII.get(ARM::tMOVgpr2tgpr), ARM::R3)
+ .addReg(ARM::R12, RegState::Kill);
+ }
} else
assert(false && "Unexpected opcode!");