diff options
| -rw-r--r-- | lib/Target/ARM/ARMRegisterInfo.cpp | 32 |
1 files changed, 23 insertions, 9 deletions
diff --git a/lib/Target/ARM/ARMRegisterInfo.cpp b/lib/Target/ARM/ARMRegisterInfo.cpp index 11198e1..7d5c88f 100644 --- a/lib/Target/ARM/ARMRegisterInfo.cpp +++ b/lib/Target/ARM/ARMRegisterInfo.cpp @@ -398,7 +398,7 @@ static unsigned calcNumMI(int Opc, int ExtraOpc, unsigned Bytes, Bytes -= ThisVal; NumMIs++; NumBits = 8; - Scale = 1; + Scale = 1; // Followed by a number of tADDi8. Chunk = ((1 << NumBits) - 1) * Scale; } @@ -685,7 +685,7 @@ void ARMRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II, const TargetInstrDescriptor &Desc = TII.get(Opcode); unsigned AddrMode = (Desc.TSFlags & ARMII::AddrModeMask); bool isSub = false; - + if (Opcode == ARM::ADDri) { Offset += MI.getOperand(i+1).getImm(); if (Offset == 0) { @@ -724,8 +724,21 @@ void ARMRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II, MI.getOperand(i+1).ChangeToImmediate(ThisSOImmVal); } else if (Opcode == ARM::tADDrSPi) { Offset += MI.getOperand(i+1).getImm(); - assert((Offset & 3) == 0 && - "Thumb add/sub sp, #imm immediate must be multiple of 4!"); + + // Can't use tADDrSPi if it's based off the frame pointer. + unsigned NumBits = 0; + unsigned Scale = 1; + if (FrameReg != ARM::SP) { + Opcode = ARM::tADDi3; + MI.setInstrDescriptor(TII.get(ARM::tADDi3)); + NumBits = 3; + } else { + NumBits = 8; + Scale = 4; + assert((Offset & 3) == 0 && + "Thumb add/sub sp, #imm immediate must be multiple of 4!"); + } + if (Offset == 0) { // Turn it into a move. MI.setInstrDescriptor(TII.get(ARM::tMOVrr)); @@ -735,16 +748,17 @@ void ARMRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II, } // Common case: small offset, fits into instruction. - if (((Offset >> 2) & ~255U) == 0) { + unsigned Mask = (1 << NumBits) - 1; + if (((Offset / Scale) & ~Mask) == 0) { // Replace the FrameIndex with sp / fp MI.getOperand(i).ChangeToRegister(FrameReg, false); - MI.getOperand(i+1).ChangeToImmediate(Offset >> 2); + MI.getOperand(i+1).ChangeToImmediate(Offset / Scale); return; } unsigned DestReg = MI.getOperand(0).getReg(); unsigned Bytes = (Offset > 0) ? Offset : -Offset; - unsigned NumMIs = calcNumMI(Opcode, 0, Bytes, 8, 1); + unsigned NumMIs = calcNumMI(Opcode, 0, Bytes, NumBits, Scale); // MI would expand into a large number of instructions. Don't try to // simplify the immediate. if (NumMIs > 2) { @@ -758,8 +772,8 @@ void ARMRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II, // r0 = add sp, 255*4 // r0 = add r0, (imm - 255*4) MI.getOperand(i).ChangeToRegister(FrameReg, false); - MI.getOperand(i+1).ChangeToImmediate(255); - Offset = (Offset - 255 * 4); + MI.getOperand(i+1).ChangeToImmediate(Mask); + Offset = (Offset - Mask * Scale); MachineBasicBlock::iterator NII = next(II); emitThumbRegPlusImmediate(MBB, NII, DestReg, DestReg, Offset, TII); } else { |