diff options
Diffstat (limited to 'lib/Target/ARM/ARMRegisterInfo.cpp')
| -rw-r--r-- | lib/Target/ARM/ARMRegisterInfo.cpp | 25 |
1 files changed, 17 insertions, 8 deletions
diff --git a/lib/Target/ARM/ARMRegisterInfo.cpp b/lib/Target/ARM/ARMRegisterInfo.cpp index a9fe705667..719ce321e0 100644 --- a/lib/Target/ARM/ARMRegisterInfo.cpp +++ b/lib/Target/ARM/ARMRegisterInfo.cpp @@ -124,10 +124,21 @@ void ARMRegisterInfo::emitPrologue(MachineFunction &MF) const { //hack assert(NumBytes == 0); - //sub sp, sp, #4 - BuildMI(MBB, MBBI, ARM::subri, 2, ARM::R13).addReg(ARM::R13).addImm(4); - //str lr, [sp] - BuildMI(MBB, MBBI, ARM::str, 1, ARM::R14).addReg(ARM::R13); + if (MFI->hasCalls()) { + // We reserve argument space for call sites in the function immediately on + // entry to the current function. This eliminates the need for add/sub + // brackets around call sites. + NumBytes += MFI->getMaxCallFrameSize(); + } + + MFI->setStackSize(NumBytes); + + //sub sp, sp, #NumBytes + BuildMI(MBB, MBBI, ARM::subri, 2, ARM::R13).addReg(ARM::R13).addImm(NumBytes); + //add ip, sp, #NumBytes - 4 + BuildMI(MBB, MBBI, ARM::addri, 2, ARM::R12).addReg(ARM::R13).addImm(NumBytes - 4); + //str lr, [ip] + BuildMI(MBB, MBBI, ARM::str, 1, ARM::R14).addReg(ARM::R12); } void ARMRegisterInfo::emitEpilogue(MachineFunction &MF, @@ -138,13 +149,11 @@ void ARMRegisterInfo::emitEpilogue(MachineFunction &MF, MachineFrameInfo *MFI = MF.getFrameInfo(); int NumBytes = (int) MFI->getStackSize(); - //hack - assert(NumBytes == 0); //ldr lr, [sp] BuildMI(MBB, MBBI, ARM::ldr, 2, ARM::R14).addImm(0).addReg(ARM::R13); - //add sp, sp, #4 - BuildMI(MBB, MBBI, ARM::addri, 2, ARM::R13).addReg(ARM::R13).addImm(4); + //add sp, sp, #NumBytes + BuildMI(MBB, MBBI, ARM::addri, 2, ARM::R13).addReg(ARM::R13).addImm(NumBytes); } unsigned ARMRegisterInfo::getRARegister() const { |