diff options
Diffstat (limited to 'llvm/lib/Target/AVR')
| -rw-r--r-- | llvm/lib/Target/AVR/AVRFrameLowering.cpp | 24 |
1 files changed, 17 insertions, 7 deletions
diff --git a/llvm/lib/Target/AVR/AVRFrameLowering.cpp b/llvm/lib/Target/AVR/AVRFrameLowering.cpp index 7e0e76182fa..3c37a1a9989 100644 --- a/llvm/lib/Target/AVR/AVRFrameLowering.cpp +++ b/llvm/lib/Target/AVR/AVRFrameLowering.cpp @@ -57,6 +57,7 @@ void AVRFrameLowering::emitPrologue(MachineFunction &MF, DebugLoc DL = (MBBI != MBB.end()) ? MBBI->getDebugLoc() : DebugLoc(); const AVRSubtarget &STI = MF.getSubtarget<AVRSubtarget>(); const AVRInstrInfo &TII = *STI.getInstrInfo(); + bool HasFP = hasFP(MF); // Interrupt handlers re-enable interrupts in function entry. if (CallConv == CallingConv::AVR_INTR) { @@ -69,9 +70,18 @@ void AVRFrameLowering::emitPrologue(MachineFunction &MF, // handlers before saving any other registers. if (CallConv == CallingConv::AVR_INTR || CallConv == CallingConv::AVR_SIGNAL) { + + // Save the frame pointer if we have one. + if (HasFP) { + BuildMI(MBB, MBBI, DL, TII.get(AVR::PUSHWRr)) + .addReg(AVR::R29R28, RegState::Kill) + .setMIFlag(MachineInstr::FrameSetup); + } + BuildMI(MBB, MBBI, DL, TII.get(AVR::PUSHWRr)) .addReg(AVR::R1R0, RegState::Kill) .setMIFlag(MachineInstr::FrameSetup); + BuildMI(MBB, MBBI, DL, TII.get(AVR::INRdA), AVR::R0) .addImm(0x3f) .setMIFlag(MachineInstr::FrameSetup); @@ -86,7 +96,7 @@ void AVRFrameLowering::emitPrologue(MachineFunction &MF, } // Early exit if the frame pointer is not needed in this function. - if (!hasFP(MF)) { + if (!HasFP) { return; } @@ -163,6 +173,9 @@ void AVRFrameLowering::emitEpilogue(MachineFunction &MF, .addImm(0x3f) .addReg(AVR::R0, RegState::Kill); BuildMI(MBB, MBBI, DL, TII.get(AVR::POPWRd), AVR::R1R0); + + if (hasFP(MF)) + BuildMI(MBB, MBBI, DL, TII.get(AVR::POPWRd), AVR::R29R28); } // Early exit if there is no need to restore the frame pointer. @@ -408,12 +421,9 @@ void AVRFrameLowering::determineCalleeSaves(MachineFunction &MF, RegScavenger *RS) const { TargetFrameLowering::determineCalleeSaves(MF, SavedRegs, RS); - // Spill register Y when it is used as the frame pointer. - if (hasFP(MF)) { - SavedRegs.set(AVR::R29R28); - SavedRegs.set(AVR::R29); - SavedRegs.set(AVR::R28); - } + // If we have a frame pointer, the Y register needs to be saved as well. + // We don't do that here however - the prologue and epilogue generation + // code will handle it specially. } /// The frame analyzer pass. /// |
