-/// Add 4 to the displacement of operand MO.
-static void fixDisp(MachineOperand &MO) {
- switch (MO.getType()) {
- default:
- llvm_unreachable("Unhandled operand type.");
- case MachineOperand::MO_Immediate:
- MO.setImm(MO.getImm() + 4);
- break;
- case MachineOperand::MO_GlobalAddress:
- case MachineOperand::MO_ConstantPoolIndex:
- case MachineOperand::MO_BlockAddress:
- case MachineOperand::MO_TargetIndex:
- case MachineOperand::MO_ExternalSymbol:
- MO.setOffset(MO.getOffset() + 4);
- break;
- }
-}
-
-void MipsSEInstrInfo::expandDPLoadStore(MachineBasicBlock &MBB,
- MachineBasicBlock::iterator I,
- unsigned OpcD, unsigned OpcS) const {
- // If NoDPLoadStore is false, just change the opcode.
- if (!NoDPLoadStore) {
- genInstrWithNewOpc(OpcD, I);
- return;
- }
-
- // Expand a double precision FP load or store to two single precision
- // instructions.
-
- const TargetRegisterInfo &TRI = getRegisterInfo();
- const MachineOperand &ValReg = I->getOperand(0);
- unsigned LoReg = TRI.getSubReg(ValReg.getReg(), Mips::sub_fpeven);
- unsigned HiReg = TRI.getSubReg(ValReg.getReg(), Mips::sub_fpodd);
-
- if (!TM.getSubtarget<MipsSubtarget>().isLittle())
- std::swap(LoReg, HiReg);
-
- // Create an instruction which loads from or stores to the lower memory
- // address.
- MachineInstrBuilder MIB = genInstrWithNewOpc(OpcS, I);
- MIB->getOperand(0).setReg(LoReg);
-
- // Create an instruction which loads from or stores to the higher memory
- // address.
- MIB = genInstrWithNewOpc(OpcS, I);
- MIB->getOperand(0).setReg(HiReg);
- fixDisp(MIB->getOperand(2));
+ if (Subtarget.hasMTHC1()) {
+ // FIXME: The .addReg(DstReg) is a white lie used to temporarily work
+ // around a widespread bug in the -mfp64 support.
+ // The problem is that none of the 32-bit fpu ops mention the fact
+ // that they clobber the upper 32-bits of the 64-bit FPR. Fixing that
+ // requires a major overhaul of the FPU implementation which can't
+ // be done right now due to time constraints.
+ // MTHC1 is one of two instructions that are affected since they are
+ // the only instructions that don't read the lower 32-bits.
+ // We therefore pretend that it reads the bottom 32-bits to
+ // artificially create a dependency and prevent the scheduler
+ // changing the behaviour of the code.
+ BuildMI(MBB, I, dl, get(FP64 ? Mips::MTHC1_D64 : Mips::MTHC1_D32), DstReg)
+ .addReg(DstReg)
+ .addReg(HiReg);
+ } else if (Subtarget.isABI_FPXX())
+ llvm_unreachable("BuildPairF64 not expanded in frame lowering code!");
+ else
+ BuildMI(MBB, I, dl, Mtc1Tdd, TRI.getSubReg(DstReg, Mips::sub_hi))
+ .addReg(HiReg);