lib/Target/MSP430/MSP430InstrInfo.cpp

   1 //===- MSP430InstrInfo.cpp - MSP430 Instruction Information ---------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file contains the MSP430 implementation of the TargetInstrInfo class.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "MSP430.h"
  15 #include "MSP430InstrInfo.h"
  16 #include "MSP430MachineFunctionInfo.h"
  17 #include "MSP430TargetMachine.h"
  18 #include "MSP430GenInstrInfo.inc"
  19 #include "llvm/Function.h"
  20 #include "llvm/CodeGen/MachineFrameInfo.h"
  21 #include "llvm/CodeGen/MachineInstrBuilder.h"
  22 #include "llvm/CodeGen/MachineRegisterInfo.h"
  23 #include "llvm/CodeGen/PseudoSourceValue.h"
  24
  25 using namespace llvm;
  26
  27 MSP430InstrInfo::MSP430InstrInfo(MSP430TargetMachine &tm)
  28   : TargetInstrInfoImpl(MSP430Insts, array_lengthof(MSP430Insts)),
  29     RI(tm, *this), TM(tm) {}
  30
  31 void MSP430InstrInfo::storeRegToStackSlot(MachineBasicBlock &MBB,
  32                                           MachineBasicBlock::iterator MI,
  33                                     unsigned SrcReg, bool isKill, int FrameIdx,
  34                                     const TargetRegisterClass *RC) const {
  35   DebugLoc DL = DebugLoc::getUnknownLoc();
  36   if (MI != MBB.end()) DL = MI->getDebugLoc();
  37
  38   if (RC == &MSP430::GR16RegClass)
  39     BuildMI(MBB, MI, DL, get(MSP430::MOV16mr))
  40       .addFrameIndex(FrameIdx).addImm(0)
  41       .addReg(SrcReg, getKillRegState(isKill));
  42   else if (RC == &MSP430::GR8RegClass)
  43     BuildMI(MBB, MI, DL, get(MSP430::MOV8mr))
  44       .addFrameIndex(FrameIdx).addImm(0)
  45       .addReg(SrcReg, getKillRegState(isKill));
  46   else
  47     assert(0 && "Cannot store this register to stack slot!");
  48 }
  49
  50 void MSP430InstrInfo::loadRegFromStackSlot(MachineBasicBlock &MBB,
  51                                            MachineBasicBlock::iterator MI,
  52                                            unsigned DestReg, int FrameIdx,
  53                                            const TargetRegisterClass *RC) const{
  54   DebugLoc DL = DebugLoc::getUnknownLoc();
  55   if (MI != MBB.end()) DL = MI->getDebugLoc();
  56
  57   if (RC == &MSP430::GR16RegClass)
  58     BuildMI(MBB, MI, DL, get(MSP430::MOV16rm))
  59       .addReg(DestReg).addFrameIndex(FrameIdx).addImm(0);
  60   else if (RC == &MSP430::GR8RegClass)
  61     BuildMI(MBB, MI, DL, get(MSP430::MOV8rm))
  62       .addReg(DestReg).addFrameIndex(FrameIdx).addImm(0);
  63   else
  64     assert(0 && "Cannot store this register to stack slot!");
  65 }
  66
  67 bool MSP430InstrInfo::copyRegToReg(MachineBasicBlock &MBB,
  68                                    MachineBasicBlock::iterator I,
  69                                    unsigned DestReg, unsigned SrcReg,
  70                                    const TargetRegisterClass *DestRC,
  71                                    const TargetRegisterClass *SrcRC) const {
  72   DebugLoc DL = DebugLoc::getUnknownLoc();
  73   if (I != MBB.end()) DL = I->getDebugLoc();
  74
  75   if (DestRC == SrcRC) {
  76     unsigned Opc;
  77     if (DestRC == &MSP430::GR16RegClass) {
  78       Opc = MSP430::MOV16rr;
  79     } else if (DestRC == &MSP430::GR8RegClass) {
  80       Opc = MSP430::MOV8rr;
  81     } else {
  82       return false;
  83     }
  84
  85     BuildMI(MBB, I, DL, get(Opc), DestReg).addReg(SrcReg);
  86     return true;
  87   }
  88
  89   return false;
  90 }
  91
  92 bool
  93 MSP430InstrInfo::isMoveInstr(const MachineInstr& MI,
  94                              unsigned &SrcReg, unsigned &DstReg,
  95                              unsigned &SrcSubIdx, unsigned &DstSubIdx) const {
  96   SrcSubIdx = DstSubIdx = 0; // No sub-registers yet.
  97
  98   switch (MI.getOpcode()) {
  99   default:
 100     return false;
 101   case MSP430::MOV8rr:
 102   case MSP430::MOV16rr:
 103    assert(MI.getNumOperands() >= 2 &&
 104            MI.getOperand(0).isReg() &&
 105            MI.getOperand(1).isReg() &&
 106            "invalid register-register move instruction");
 107     SrcReg = MI.getOperand(1).getReg();
 108     DstReg = MI.getOperand(0).getReg();
 109     return true;
 110   }
 111 }
 112
 113 bool
 114 MSP430InstrInfo::spillCalleeSavedRegisters(MachineBasicBlock &MBB,
 115                                            MachineBasicBlock::iterator MI,
 116                                 const std::vector<CalleeSavedInfo> &CSI) const {
 117   if (CSI.empty())
 118     return false;
 119
 120   DebugLoc DL = DebugLoc::getUnknownLoc();
 121   if (MI != MBB.end()) DL = MI->getDebugLoc();
 122
 123   MachineFunction &MF = *MBB.getParent();
 124   MSP430MachineFunctionInfo *MFI = MF.getInfo<MSP430MachineFunctionInfo>();
 125   MFI->setCalleeSavedFrameSize(CSI.size() * 2);
 126
 127   for (unsigned i = CSI.size(); i != 0; --i) {
 128     unsigned Reg = CSI[i-1].getReg();
 129     // Add the callee-saved register as live-in. It's killed at the spill.
 130     MBB.addLiveIn(Reg);
 131     BuildMI(MBB, MI, DL, get(MSP430::PUSH16r))
 132       .addReg(Reg, RegState::Kill);
 133   }
 134   return true;
 135 }
 136
 137 bool
 138 MSP430InstrInfo::restoreCalleeSavedRegisters(MachineBasicBlock &MBB,
 139                                              MachineBasicBlock::iterator MI,
 140                                 const std::vector<CalleeSavedInfo> &CSI) const {
 141   if (CSI.empty())
 142     return false;
 143
 144   DebugLoc DL = DebugLoc::getUnknownLoc();
 145   if (MI != MBB.end()) DL = MI->getDebugLoc();
 146
 147   for (unsigned i = 0, e = CSI.size(); i != e; ++i)
 148     BuildMI(MBB, MI, DL, get(MSP430::POP16r), CSI[i].getReg());
 149
 150   return true;
 151 }
 152
 153 unsigned
 154 MSP430InstrInfo::InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
 155                               MachineBasicBlock *FBB,
 156                             const SmallVectorImpl<MachineOperand> &Cond) const {
 157   // FIXME this should probably have a DebugLoc operand
 158   DebugLoc dl = DebugLoc::getUnknownLoc();
 159
 160   // Shouldn't be a fall through.
 161   assert(TBB && "InsertBranch must not be told to insert a fallthrough");
 162   assert((Cond.size() == 1 || Cond.size() == 0) &&
 163          "MSP430 branch conditions have one component!");
 164
 165   if (Cond.empty()) {
 166     // Unconditional branch?
 167     assert(!FBB && "Unconditional branch with multiple successors!");
 168     BuildMI(&MBB, dl, get(MSP430::JMP)).addMBB(TBB);
 169     return 1;
 170   }
 171
 172   // Conditional branch.
 173   unsigned Count = 0;
 174   assert(0 && "Implement conditional branches!");
 175
 176   return Count;
 177 }