|  | //===- MSP430InstrInfo.cpp - MSP430 Instruction Information ---------------===// | 
|  | // | 
|  | //                     The LLVM Compiler Infrastructure | 
|  | // | 
|  | // This file is distributed under the University of Illinois Open Source | 
|  | // License. See LICENSE.TXT for details. | 
|  | // | 
|  | //===----------------------------------------------------------------------===// | 
|  | // | 
|  | // This file contains the MSP430 implementation of the TargetInstrInfo class. | 
|  | // | 
|  | //===----------------------------------------------------------------------===// | 
|  |  | 
|  | #include "MSP430.h" | 
|  | #include "MSP430InstrInfo.h" | 
|  | #include "MSP430MachineFunctionInfo.h" | 
|  | #include "MSP430TargetMachine.h" | 
|  | #include "MSP430GenInstrInfo.inc" | 
|  | #include "llvm/Function.h" | 
|  | #include "llvm/CodeGen/MachineFrameInfo.h" | 
|  | #include "llvm/CodeGen/MachineInstrBuilder.h" | 
|  | #include "llvm/CodeGen/MachineRegisterInfo.h" | 
|  | #include "llvm/CodeGen/PseudoSourceValue.h" | 
|  | #include "llvm/Support/ErrorHandling.h" | 
|  |  | 
|  | using namespace llvm; | 
|  |  | 
|  | MSP430InstrInfo::MSP430InstrInfo(MSP430TargetMachine &tm) | 
|  | : TargetInstrInfoImpl(MSP430Insts, array_lengthof(MSP430Insts)), | 
|  | RI(tm, *this), TM(tm) {} | 
|  |  | 
|  | void MSP430InstrInfo::storeRegToStackSlot(MachineBasicBlock &MBB, | 
|  | MachineBasicBlock::iterator MI, | 
|  | unsigned SrcReg, bool isKill, int FrameIdx, | 
|  | const TargetRegisterClass *RC, | 
|  | const TargetRegisterInfo *TRI) const { | 
|  | DebugLoc DL; | 
|  | if (MI != MBB.end()) DL = MI->getDebugLoc(); | 
|  | MachineFunction &MF = *MBB.getParent(); | 
|  | MachineFrameInfo &MFI = *MF.getFrameInfo(); | 
|  |  | 
|  | MachineMemOperand *MMO = | 
|  | MF.getMachineMemOperand( | 
|  | MachinePointerInfo(PseudoSourceValue::getFixedStack(FrameIdx)), | 
|  | MachineMemOperand::MOStore, | 
|  | MFI.getObjectSize(FrameIdx), | 
|  | MFI.getObjectAlignment(FrameIdx)); | 
|  |  | 
|  | if (RC == &MSP430::GR16RegClass) | 
|  | BuildMI(MBB, MI, DL, get(MSP430::MOV16mr)) | 
|  | .addFrameIndex(FrameIdx).addImm(0) | 
|  | .addReg(SrcReg, getKillRegState(isKill)).addMemOperand(MMO); | 
|  | else if (RC == &MSP430::GR8RegClass) | 
|  | BuildMI(MBB, MI, DL, get(MSP430::MOV8mr)) | 
|  | .addFrameIndex(FrameIdx).addImm(0) | 
|  | .addReg(SrcReg, getKillRegState(isKill)).addMemOperand(MMO); | 
|  | else | 
|  | llvm_unreachable("Cannot store this register to stack slot!"); | 
|  | } | 
|  |  | 
|  | void MSP430InstrInfo::loadRegFromStackSlot(MachineBasicBlock &MBB, | 
|  | MachineBasicBlock::iterator MI, | 
|  | unsigned DestReg, int FrameIdx, | 
|  | const TargetRegisterClass *RC, | 
|  | const TargetRegisterInfo *TRI) const{ | 
|  | DebugLoc DL; | 
|  | if (MI != MBB.end()) DL = MI->getDebugLoc(); | 
|  | MachineFunction &MF = *MBB.getParent(); | 
|  | MachineFrameInfo &MFI = *MF.getFrameInfo(); | 
|  |  | 
|  | MachineMemOperand *MMO = | 
|  | MF.getMachineMemOperand( | 
|  | MachinePointerInfo(PseudoSourceValue::getFixedStack(FrameIdx)), | 
|  | MachineMemOperand::MOLoad, | 
|  | MFI.getObjectSize(FrameIdx), | 
|  | MFI.getObjectAlignment(FrameIdx)); | 
|  |  | 
|  | if (RC == &MSP430::GR16RegClass) | 
|  | BuildMI(MBB, MI, DL, get(MSP430::MOV16rm)) | 
|  | .addReg(DestReg).addFrameIndex(FrameIdx).addImm(0).addMemOperand(MMO); | 
|  | else if (RC == &MSP430::GR8RegClass) | 
|  | BuildMI(MBB, MI, DL, get(MSP430::MOV8rm)) | 
|  | .addReg(DestReg).addFrameIndex(FrameIdx).addImm(0).addMemOperand(MMO); | 
|  | else | 
|  | llvm_unreachable("Cannot store this register to stack slot!"); | 
|  | } | 
|  |  | 
|  | void MSP430InstrInfo::copyPhysReg(MachineBasicBlock &MBB, | 
|  | MachineBasicBlock::iterator I, DebugLoc DL, | 
|  | unsigned DestReg, unsigned SrcReg, | 
|  | bool KillSrc) const { | 
|  | unsigned Opc; | 
|  | if (MSP430::GR16RegClass.contains(DestReg, SrcReg)) | 
|  | Opc = MSP430::MOV16rr; | 
|  | else if (MSP430::GR8RegClass.contains(DestReg, SrcReg)) | 
|  | Opc = MSP430::MOV8rr; | 
|  | else | 
|  | llvm_unreachable("Impossible reg-to-reg copy"); | 
|  |  | 
|  | BuildMI(MBB, I, DL, get(Opc), DestReg) | 
|  | .addReg(SrcReg, getKillRegState(KillSrc)); | 
|  | } | 
|  |  | 
|  | bool | 
|  | MSP430InstrInfo::spillCalleeSavedRegisters(MachineBasicBlock &MBB, | 
|  | MachineBasicBlock::iterator MI, | 
|  | const std::vector<CalleeSavedInfo> &CSI, | 
|  | const TargetRegisterInfo *TRI) const { | 
|  | if (CSI.empty()) | 
|  | return false; | 
|  |  | 
|  | DebugLoc DL; | 
|  | if (MI != MBB.end()) DL = MI->getDebugLoc(); | 
|  |  | 
|  | MachineFunction &MF = *MBB.getParent(); | 
|  | MSP430MachineFunctionInfo *MFI = MF.getInfo<MSP430MachineFunctionInfo>(); | 
|  | MFI->setCalleeSavedFrameSize(CSI.size() * 2); | 
|  |  | 
|  | for (unsigned i = CSI.size(); i != 0; --i) { | 
|  | unsigned Reg = CSI[i-1].getReg(); | 
|  | // Add the callee-saved register as live-in. It's killed at the spill. | 
|  | MBB.addLiveIn(Reg); | 
|  | BuildMI(MBB, MI, DL, get(MSP430::PUSH16r)) | 
|  | .addReg(Reg, RegState::Kill); | 
|  | } | 
|  | return true; | 
|  | } | 
|  |  | 
|  | bool | 
|  | MSP430InstrInfo::restoreCalleeSavedRegisters(MachineBasicBlock &MBB, | 
|  | MachineBasicBlock::iterator MI, | 
|  | const std::vector<CalleeSavedInfo> &CSI, | 
|  | const TargetRegisterInfo *TRI) const { | 
|  | if (CSI.empty()) | 
|  | return false; | 
|  |  | 
|  | DebugLoc DL; | 
|  | if (MI != MBB.end()) DL = MI->getDebugLoc(); | 
|  |  | 
|  | for (unsigned i = 0, e = CSI.size(); i != e; ++i) | 
|  | BuildMI(MBB, MI, DL, get(MSP430::POP16r), CSI[i].getReg()); | 
|  |  | 
|  | return true; | 
|  | } | 
|  |  | 
|  | unsigned MSP430InstrInfo::RemoveBranch(MachineBasicBlock &MBB) const { | 
|  | MachineBasicBlock::iterator I = MBB.end(); | 
|  | unsigned Count = 0; | 
|  |  | 
|  | while (I != MBB.begin()) { | 
|  | --I; | 
|  | if (I->isDebugValue()) | 
|  | continue; | 
|  | if (I->getOpcode() != MSP430::JMP && | 
|  | I->getOpcode() != MSP430::JCC && | 
|  | I->getOpcode() != MSP430::Br && | 
|  | I->getOpcode() != MSP430::Bm) | 
|  | break; | 
|  | // Remove the branch. | 
|  | I->eraseFromParent(); | 
|  | I = MBB.end(); | 
|  | ++Count; | 
|  | } | 
|  |  | 
|  | return Count; | 
|  | } | 
|  |  | 
|  | bool MSP430InstrInfo:: | 
|  | ReverseBranchCondition(SmallVectorImpl<MachineOperand> &Cond) const { | 
|  | assert(Cond.size() == 1 && "Invalid Xbranch condition!"); | 
|  |  | 
|  | MSP430CC::CondCodes CC = static_cast<MSP430CC::CondCodes>(Cond[0].getImm()); | 
|  |  | 
|  | switch (CC) { | 
|  | default: | 
|  | assert(0 && "Invalid branch condition!"); | 
|  | break; | 
|  | case MSP430CC::COND_E: | 
|  | CC = MSP430CC::COND_NE; | 
|  | break; | 
|  | case MSP430CC::COND_NE: | 
|  | CC = MSP430CC::COND_E; | 
|  | break; | 
|  | case MSP430CC::COND_L: | 
|  | CC = MSP430CC::COND_GE; | 
|  | break; | 
|  | case MSP430CC::COND_GE: | 
|  | CC = MSP430CC::COND_L; | 
|  | break; | 
|  | case MSP430CC::COND_HS: | 
|  | CC = MSP430CC::COND_LO; | 
|  | break; | 
|  | case MSP430CC::COND_LO: | 
|  | CC = MSP430CC::COND_HS; | 
|  | break; | 
|  | } | 
|  |  | 
|  | Cond[0].setImm(CC); | 
|  | return false; | 
|  | } | 
|  |  | 
|  | bool MSP430InstrInfo::isUnpredicatedTerminator(const MachineInstr *MI) const { | 
|  | const TargetInstrDesc &TID = MI->getDesc(); | 
|  | if (!TID.isTerminator()) return false; | 
|  |  | 
|  | // Conditional branch is a special case. | 
|  | if (TID.isBranch() && !TID.isBarrier()) | 
|  | return true; | 
|  | if (!TID.isPredicable()) | 
|  | return true; | 
|  | return !isPredicated(MI); | 
|  | } | 
|  |  | 
|  | bool MSP430InstrInfo::AnalyzeBranch(MachineBasicBlock &MBB, | 
|  | MachineBasicBlock *&TBB, | 
|  | MachineBasicBlock *&FBB, | 
|  | SmallVectorImpl<MachineOperand> &Cond, | 
|  | bool AllowModify) const { | 
|  | // Start from the bottom of the block and work up, examining the | 
|  | // terminator instructions. | 
|  | MachineBasicBlock::iterator I = MBB.end(); | 
|  | while (I != MBB.begin()) { | 
|  | --I; | 
|  | if (I->isDebugValue()) | 
|  | continue; | 
|  |  | 
|  | // Working from the bottom, when we see a non-terminator | 
|  | // instruction, we're done. | 
|  | if (!isUnpredicatedTerminator(I)) | 
|  | break; | 
|  |  | 
|  | // A terminator that isn't a branch can't easily be handled | 
|  | // by this analysis. | 
|  | if (!I->getDesc().isBranch()) | 
|  | return true; | 
|  |  | 
|  | // Cannot handle indirect branches. | 
|  | if (I->getOpcode() == MSP430::Br || | 
|  | I->getOpcode() == MSP430::Bm) | 
|  | return true; | 
|  |  | 
|  | // Handle unconditional branches. | 
|  | if (I->getOpcode() == MSP430::JMP) { | 
|  | if (!AllowModify) { | 
|  | TBB = I->getOperand(0).getMBB(); | 
|  | continue; | 
|  | } | 
|  |  | 
|  | // If the block has any instructions after a JMP, delete them. | 
|  | while (llvm::next(I) != MBB.end()) | 
|  | llvm::next(I)->eraseFromParent(); | 
|  | Cond.clear(); | 
|  | FBB = 0; | 
|  |  | 
|  | // Delete the JMP if it's equivalent to a fall-through. | 
|  | if (MBB.isLayoutSuccessor(I->getOperand(0).getMBB())) { | 
|  | TBB = 0; | 
|  | I->eraseFromParent(); | 
|  | I = MBB.end(); | 
|  | continue; | 
|  | } | 
|  |  | 
|  | // TBB is used to indicate the unconditinal destination. | 
|  | TBB = I->getOperand(0).getMBB(); | 
|  | continue; | 
|  | } | 
|  |  | 
|  | // Handle conditional branches. | 
|  | assert(I->getOpcode() == MSP430::JCC && "Invalid conditional branch"); | 
|  | MSP430CC::CondCodes BranchCode = | 
|  | static_cast<MSP430CC::CondCodes>(I->getOperand(1).getImm()); | 
|  | if (BranchCode == MSP430CC::COND_INVALID) | 
|  | return true;  // Can't handle weird stuff. | 
|  |  | 
|  | // Working from the bottom, handle the first conditional branch. | 
|  | if (Cond.empty()) { | 
|  | FBB = TBB; | 
|  | TBB = I->getOperand(0).getMBB(); | 
|  | Cond.push_back(MachineOperand::CreateImm(BranchCode)); | 
|  | continue; | 
|  | } | 
|  |  | 
|  | // Handle subsequent conditional branches. Only handle the case where all | 
|  | // conditional branches branch to the same destination. | 
|  | assert(Cond.size() == 1); | 
|  | assert(TBB); | 
|  |  | 
|  | // Only handle the case where all conditional branches branch to | 
|  | // the same destination. | 
|  | if (TBB != I->getOperand(0).getMBB()) | 
|  | return true; | 
|  |  | 
|  | MSP430CC::CondCodes OldBranchCode = (MSP430CC::CondCodes)Cond[0].getImm(); | 
|  | // If the conditions are the same, we can leave them alone. | 
|  | if (OldBranchCode == BranchCode) | 
|  | continue; | 
|  |  | 
|  | return true; | 
|  | } | 
|  |  | 
|  | return false; | 
|  | } | 
|  |  | 
|  | unsigned | 
|  | MSP430InstrInfo::InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB, | 
|  | MachineBasicBlock *FBB, | 
|  | const SmallVectorImpl<MachineOperand> &Cond, | 
|  | DebugLoc DL) const { | 
|  | // Shouldn't be a fall through. | 
|  | assert(TBB && "InsertBranch must not be told to insert a fallthrough"); | 
|  | assert((Cond.size() == 1 || Cond.size() == 0) && | 
|  | "MSP430 branch conditions have one component!"); | 
|  |  | 
|  | if (Cond.empty()) { | 
|  | // Unconditional branch? | 
|  | assert(!FBB && "Unconditional branch with multiple successors!"); | 
|  | BuildMI(&MBB, DL, get(MSP430::JMP)).addMBB(TBB); | 
|  | return 1; | 
|  | } | 
|  |  | 
|  | // Conditional branch. | 
|  | unsigned Count = 0; | 
|  | BuildMI(&MBB, DL, get(MSP430::JCC)).addMBB(TBB).addImm(Cond[0].getImm()); | 
|  | ++Count; | 
|  |  | 
|  | if (FBB) { | 
|  | // Two-way Conditional branch. Insert the second branch. | 
|  | BuildMI(&MBB, DL, get(MSP430::JMP)).addMBB(FBB); | 
|  | ++Count; | 
|  | } | 
|  | return Count; | 
|  | } | 
|  |  | 
|  | /// GetInstSize - Return the number of bytes of code the specified | 
|  | /// instruction may be.  This returns the maximum number of bytes. | 
|  | /// | 
|  | unsigned MSP430InstrInfo::GetInstSizeInBytes(const MachineInstr *MI) const { | 
|  | const TargetInstrDesc &Desc = MI->getDesc(); | 
|  |  | 
|  | switch (Desc.TSFlags & MSP430II::SizeMask) { | 
|  | default: | 
|  | switch (Desc.getOpcode()) { | 
|  | default: | 
|  | assert(0 && "Unknown instruction size!"); | 
|  | case TargetOpcode::PROLOG_LABEL: | 
|  | case TargetOpcode::EH_LABEL: | 
|  | case TargetOpcode::IMPLICIT_DEF: | 
|  | case TargetOpcode::KILL: | 
|  | case TargetOpcode::DBG_VALUE: | 
|  | return 0; | 
|  | case TargetOpcode::INLINEASM: { | 
|  | const MachineFunction *MF = MI->getParent()->getParent(); | 
|  | const TargetInstrInfo &TII = *MF->getTarget().getInstrInfo(); | 
|  | return TII.getInlineAsmLength(MI->getOperand(0).getSymbolName(), | 
|  | *MF->getTarget().getMCAsmInfo()); | 
|  | } | 
|  | } | 
|  | case MSP430II::SizeSpecial: | 
|  | switch (MI->getOpcode()) { | 
|  | default: | 
|  | assert(0 && "Unknown instruction size!"); | 
|  | case MSP430::SAR8r1c: | 
|  | case MSP430::SAR16r1c: | 
|  | return 4; | 
|  | } | 
|  | case MSP430II::Size2Bytes: | 
|  | return 2; | 
|  | case MSP430II::Size4Bytes: | 
|  | return 4; | 
|  | case MSP430II::Size6Bytes: | 
|  | return 6; | 
|  | } | 
|  |  | 
|  | return 6; | 
|  | } |