diff --git a/lib/Target/PowerPC/PPCRegisterInfo.cpp b/lib/Target/PowerPC/PPCRegisterInfo.cpp index 20e77e79c5a..0b509ac161a 100644 --- a/lib/Target/PowerPC/PPCRegisterInfo.cpp +++ b/lib/Target/PowerPC/PPCRegisterInfo.cpp @@ -427,6 +427,12 @@ BitVector PPCRegisterInfo::getReservedRegs(const MachineFunction &MF) const { Reserved.set(PPC::R2); // System-reserved register Reserved.set(PPC::R13); // Small Data Area pointer register } + // Reserve R2 on Darwin to hack around the problem of save/restore of CR + // when the stack frame is too big to address directly; we need two regs. + // This is a hack. + if (Subtarget.isDarwinABI()) { + Reserved.set(PPC::R2); + } // On PPC64, r13 is the thread pointer. Never allocate this register. // Note that this is over conservative, as it also prevents allocation of R31 @@ -447,6 +453,12 @@ BitVector PPCRegisterInfo::getReservedRegs(const MachineFunction &MF) const { if (Subtarget.isSVR4ABI()) { Reserved.set(PPC::X2); } + // Reserve R2 on Darwin to hack around the problem of save/restore of CR + // when the stack frame is too big to address directly; we need two regs. + // This is a hack. + if (Subtarget.isDarwinABI()) { + Reserved.set(PPC::X2); + } } if (needsFP(MF))