diff options
Diffstat (limited to 'llvm/lib/Target/PowerPC/PPCFrameLowering.cpp')
| -rw-r--r-- | llvm/lib/Target/PowerPC/PPCFrameLowering.cpp | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/llvm/lib/Target/PowerPC/PPCFrameLowering.cpp b/llvm/lib/Target/PowerPC/PPCFrameLowering.cpp index 82746c1d58b..b2577a9c7cf 100644 --- a/llvm/lib/Target/PowerPC/PPCFrameLowering.cpp +++ b/llvm/lib/Target/PowerPC/PPCFrameLowering.cpp @@ -514,6 +514,7 @@ void PPCFrameLowering::emitPrologue(MachineFunction &MF) const { // Get the ABI. bool isDarwinABI = Subtarget.isDarwinABI(); bool isSVR4ABI = Subtarget.isSVR4ABI(); + bool isELFv2ABI = Subtarget.isELFv2ABI(); assert((isDarwinABI || isSVR4ABI) && "Currently only Darwin and SVR4 ABIs are supported for PowerPC."); @@ -627,6 +628,9 @@ void PPCFrameLowering::emitPrologue(MachineFunction &MF) const { "Prologue CR saving supported only in 64-bit mode"); if (!MustSaveCRs.empty()) { // will only occur for PPC64 + // FIXME: In the ELFv2 ABI, we are not required to save all CR fields. + // If only one or two CR fields are clobbered, it could be more + // efficient to use mfocrf to selectively save just those fields. MachineInstrBuilder MIB = BuildMI(MBB, MBBI, dl, TII.get(PPC::MFCR8), TempReg); for (unsigned i = 0, e = MustSaveCRs.size(); i != e; ++i) @@ -795,8 +799,12 @@ void PPCFrameLowering::emitPrologue(MachineFunction &MF) const { // For 64-bit SVR4 when we have spilled CRs, the spill location // is SP+8, not a frame-relative slot. if (isSVR4ABI && isPPC64 && (PPC::CR2 <= Reg && Reg <= PPC::CR4)) { + // In the ELFv1 ABI, only CR2 is noted in CFI and stands in for + // the whole CR word. In the ELFv2 ABI, every CR that was + // actually saved gets its own CFI record. + unsigned CRReg = isELFv2ABI? Reg : (unsigned) PPC::CR2; unsigned CFIIndex = MMI.addFrameInst(MCCFIInstruction::createOffset( - nullptr, MRI->getDwarfRegNum(PPC::CR2, true), 8)); + nullptr, MRI->getDwarfRegNum(CRReg, true), 8)); BuildMI(MBB, MBBI, dl, TII.get(TargetOpcode::CFI_INSTRUCTION)) .addCFIIndex(CFIIndex); continue; |
