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 #include "llvm/Support/ErrorHandling.h"
  25
  26 using namespace llvm;
  27
  28 MSP430InstrInfo::MSP430InstrInfo(MSP430TargetMachine &tm)
  29   : TargetInstrInfoImpl(MSP430Insts, array_lengthof(MSP430Insts)),
  30     RI(tm, *this), TM(tm) {}
  31
  32 void MSP430InstrInfo::storeRegToStackSlot(MachineBasicBlock &MBB,
  33                                           MachineBasicBlock::iterator MI,
  34                                     unsigned SrcReg, bool isKill, int FrameIdx,
  35                                     const TargetRegisterClass *RC) const {
  36   DebugLoc DL = DebugLoc::getUnknownLoc();
  37   if (MI != MBB.end()) DL = MI->getDebugLoc();
  38
  39   if (RC == &MSP430::GR16RegClass)
  40     BuildMI(MBB, MI, DL, get(MSP430::MOV16mr))
  41       .addFrameIndex(FrameIdx).addImm(0)
  42       .addReg(SrcReg, getKillRegState(isKill));
  43   else if (RC == &MSP430::GR8RegClass)
  44     BuildMI(MBB, MI, DL, get(MSP430::MOV8mr))
  45       .addFrameIndex(FrameIdx).addImm(0)
  46       .addReg(SrcReg, getKillRegState(isKill));
  47   else
  48     llvm_unreachable("Cannot store this register to stack slot!");
  49 }
  50
  51 void MSP430InstrInfo::loadRegFromStackSlot(MachineBasicBlock &MBB,
  52                                            MachineBasicBlock::iterator MI,
  53                                            unsigned DestReg, int FrameIdx,
  54                                            const TargetRegisterClass *RC) const{
  55   DebugLoc DL = DebugLoc::getUnknownLoc();
  56   if (MI != MBB.end()) DL = MI->getDebugLoc();
  57
  58   if (RC == &MSP430::GR16RegClass)
  59     BuildMI(MBB, MI, DL, get(MSP430::MOV16rm))
  60       .addReg(DestReg).addFrameIndex(FrameIdx).addImm(0);
  61   else if (RC == &MSP430::GR8RegClass)
  62     BuildMI(MBB, MI, DL, get(MSP430::MOV8rm))
  63       .addReg(DestReg).addFrameIndex(FrameIdx).addImm(0);
  64   else
  65     llvm_unreachable("Cannot store this register to stack slot!");
  66 }
  67
  68 bool MSP430InstrInfo::copyRegToReg(MachineBasicBlock &MBB,
  69                                    MachineBasicBlock::iterator I,
  70                                    unsigned DestReg, unsigned SrcReg,
  71                                    const TargetRegisterClass *DestRC,
  72                                    const TargetRegisterClass *SrcRC) const {
  73   DebugLoc DL = DebugLoc::getUnknownLoc();
  74   if (I != MBB.end()) DL = I->getDebugLoc();
  75
  76   if (DestRC == SrcRC) {
  77     unsigned Opc;
  78     if (DestRC == &MSP430::GR16RegClass) {
  79       Opc = MSP430::MOV16rr;
  80     } else if (DestRC == &MSP430::GR8RegClass) {
  81       Opc = MSP430::MOV8rr;
  82     } else {
  83       return false;
  84     }
  85
  86     BuildMI(MBB, I, DL, get(Opc), DestReg).addReg(SrcReg);
  87     return true;
  88   }
  89
  90   return false;
  91 }
  92
  93 bool
  94 MSP430InstrInfo::isMoveInstr(const MachineInstr& MI,
  95                              unsigned &SrcReg, unsigned &DstReg,
  96                              unsigned &SrcSubIdx, unsigned &DstSubIdx) const {
  97   SrcSubIdx = DstSubIdx = 0; // No sub-registers yet.
  98
  99   switch (MI.getOpcode()) {
 100   default:
 101     return false;
 102   case MSP430::MOV8rr:
 103   case MSP430::MOV16rr:
 104    assert(MI.getNumOperands() >= 2 &&
 105            MI.getOperand(0).isReg() &&
 106            MI.getOperand(1).isReg() &&
 107            "invalid register-register move instruction");
 108     SrcReg = MI.getOperand(1).getReg();
 109     DstReg = MI.getOperand(0).getReg();
 110     return true;
 111   }
 112 }
 113
 114 bool
 115 MSP430InstrInfo::spillCalleeSavedRegisters(MachineBasicBlock &MBB,
 116                                            MachineBasicBlock::iterator MI,
 117                                 const std::vector<CalleeSavedInfo> &CSI) const {
 118   if (CSI.empty())
 119     return false;
 120
 121   DebugLoc DL = DebugLoc::getUnknownLoc();
 122   if (MI != MBB.end()) DL = MI->getDebugLoc();
 123
 124   MachineFunction &MF = *MBB.getParent();
 125   MSP430MachineFunctionInfo *MFI = MF.getInfo<MSP430MachineFunctionInfo>();
 126   MFI->setCalleeSavedFrameSize(CSI.size() * 2);
 127
 128   for (unsigned i = CSI.size(); i != 0; --i) {
 129     unsigned Reg = CSI[i-1].getReg();
 130     // Add the callee-saved register as live-in. It's killed at the spill.
 131     MBB.addLiveIn(Reg);
 132     BuildMI(MBB, MI, DL, get(MSP430::PUSH16r))
 133       .addReg(Reg, RegState::Kill);
 134   }
 135   return true;
 136 }
 137
 138 bool
 139 MSP430InstrInfo::restoreCalleeSavedRegisters(MachineBasicBlock &MBB,
 140                                              MachineBasicBlock::iterator MI,
 141                                 const std::vector<CalleeSavedInfo> &CSI) const {
 142   if (CSI.empty())
 143     return false;
 144
 145   DebugLoc DL = DebugLoc::getUnknownLoc();
 146   if (MI != MBB.end()) DL = MI->getDebugLoc();
 147
 148   for (unsigned i = 0, e = CSI.size(); i != e; ++i)
 149     BuildMI(MBB, MI, DL, get(MSP430::POP16r), CSI[i].getReg());
 150
 151   return true;
 152 }
 153
 154 unsigned
 155 MSP430InstrInfo::InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
 156                               MachineBasicBlock *FBB,
 157                             const SmallVectorImpl<MachineOperand> &Cond) const {
 158   // FIXME this should probably have a DebugLoc operand
 159   DebugLoc dl = DebugLoc::getUnknownLoc();
 160
 161   // Shouldn't be a fall through.
 162   assert(TBB && "InsertBranch must not be told to insert a fallthrough");
 163   assert((Cond.size() == 1 || Cond.size() == 0) &&
 164          "MSP430 branch conditions have one component!");
 165
 166   if (Cond.empty()) {
 167     // Unconditional branch?
 168     assert(!FBB && "Unconditional branch with multiple successors!");
 169     BuildMI(&MBB, dl, get(MSP430::JMP)).addMBB(TBB);
 170     return 1;
 171   }
 172
 173   // Conditional branch.
 174   unsigned Count = 0;
 175   llvm_unreachable("Implement conditional branches!");
 176
 177   return Count;
 178 }