Thumb1InstrInfo.cpp revision 34dcc6fadca0a1117cdbd0e9b35c991a55b6e556
1//===- Thumb1InstrInfo.cpp - Thumb-1 Instruction Information ----*- C++ -*-===// 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 Thumb-1 implementation of the TargetInstrInfo class. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Thumb1InstrInfo.h" 15#include "ARM.h" 16#include "ARMGenInstrInfo.inc" 17#include "ARMMachineFunctionInfo.h" 18#include "llvm/CodeGen/MachineFrameInfo.h" 19#include "llvm/CodeGen/MachineInstrBuilder.h" 20#include "llvm/CodeGen/MachineMemOperand.h" 21#include "llvm/CodeGen/PseudoSourceValue.h" 22#include "llvm/ADT/SmallVector.h" 23#include "Thumb1InstrInfo.h" 24 25using namespace llvm; 26 27Thumb1InstrInfo::Thumb1InstrInfo(const ARMSubtarget &STI) 28 : ARMBaseInstrInfo(STI), RI(*this, STI) { 29} 30 31unsigned Thumb1InstrInfo::getUnindexedOpcode(unsigned Opc) const { 32 return 0; 33} 34 35bool Thumb1InstrInfo::copyRegToReg(MachineBasicBlock &MBB, 36 MachineBasicBlock::iterator I, 37 unsigned DestReg, unsigned SrcReg, 38 const TargetRegisterClass *DestRC, 39 const TargetRegisterClass *SrcRC, 40 DebugLoc DL) const { 41 if (DestRC == ARM::GPRRegisterClass) { 42 if (SrcRC == ARM::GPRRegisterClass) { 43 BuildMI(MBB, I, DL, get(ARM::tMOVgpr2gpr), DestReg).addReg(SrcReg); 44 return true; 45 } else if (SrcRC == ARM::tGPRRegisterClass) { 46 BuildMI(MBB, I, DL, get(ARM::tMOVtgpr2gpr), DestReg).addReg(SrcReg); 47 return true; 48 } 49 } else if (DestRC == ARM::tGPRRegisterClass) { 50 if (SrcRC == ARM::GPRRegisterClass) { 51 BuildMI(MBB, I, DL, get(ARM::tMOVgpr2tgpr), DestReg).addReg(SrcReg); 52 return true; 53 } else if (SrcRC == ARM::tGPRRegisterClass) { 54 BuildMI(MBB, I, DL, get(ARM::tMOVr), DestReg).addReg(SrcReg); 55 return true; 56 } 57 } 58 59 return false; 60} 61 62bool Thumb1InstrInfo:: 63canFoldMemoryOperand(const MachineInstr *MI, 64 const SmallVectorImpl<unsigned> &Ops) const { 65 if (Ops.size() != 1) return false; 66 67 unsigned OpNum = Ops[0]; 68 unsigned Opc = MI->getOpcode(); 69 switch (Opc) { 70 default: break; 71 case ARM::tMOVr: 72 case ARM::tMOVtgpr2gpr: 73 case ARM::tMOVgpr2tgpr: 74 case ARM::tMOVgpr2gpr: { 75 if (OpNum == 0) { // move -> store 76 unsigned SrcReg = MI->getOperand(1).getReg(); 77 if (TargetRegisterInfo::isPhysicalRegister(SrcReg) && 78 !isARMLowRegister(SrcReg)) 79 // tSpill cannot take a high register operand. 80 return false; 81 } else { // move -> load 82 unsigned DstReg = MI->getOperand(0).getReg(); 83 if (TargetRegisterInfo::isPhysicalRegister(DstReg) && 84 !isARMLowRegister(DstReg)) 85 // tRestore cannot target a high register operand. 86 return false; 87 } 88 return true; 89 } 90 } 91 92 return false; 93} 94 95void Thumb1InstrInfo:: 96storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, 97 unsigned SrcReg, bool isKill, int FI, 98 const TargetRegisterClass *RC, 99 const TargetRegisterInfo *TRI) const { 100 assert((RC == ARM::tGPRRegisterClass || 101 (TargetRegisterInfo::isPhysicalRegister(SrcReg) && 102 isARMLowRegister(SrcReg))) && "Unknown regclass!"); 103 104 if (RC == ARM::tGPRRegisterClass || 105 (TargetRegisterInfo::isPhysicalRegister(SrcReg) && 106 isARMLowRegister(SrcReg))) { 107 DebugLoc DL; 108 if (I != MBB.end()) DL = I->getDebugLoc(); 109 110 MachineFunction &MF = *MBB.getParent(); 111 MachineFrameInfo &MFI = *MF.getFrameInfo(); 112 MachineMemOperand *MMO = 113 MF.getMachineMemOperand(PseudoSourceValue::getFixedStack(FI), 114 MachineMemOperand::MOStore, 0, 115 MFI.getObjectSize(FI), 116 MFI.getObjectAlignment(FI)); 117 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::tSpill)) 118 .addReg(SrcReg, getKillRegState(isKill)) 119 .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); 120 } 121} 122 123void Thumb1InstrInfo:: 124loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, 125 unsigned DestReg, int FI, 126 const TargetRegisterClass *RC, 127 const TargetRegisterInfo *TRI) const { 128 assert((RC == ARM::tGPRRegisterClass || 129 (TargetRegisterInfo::isPhysicalRegister(DestReg) && 130 isARMLowRegister(DestReg))) && "Unknown regclass!"); 131 132 if (RC == ARM::tGPRRegisterClass || 133 (TargetRegisterInfo::isPhysicalRegister(DestReg) && 134 isARMLowRegister(DestReg))) { 135 DebugLoc DL; 136 if (I != MBB.end()) DL = I->getDebugLoc(); 137 138 MachineFunction &MF = *MBB.getParent(); 139 MachineFrameInfo &MFI = *MF.getFrameInfo(); 140 MachineMemOperand *MMO = 141 MF.getMachineMemOperand(PseudoSourceValue::getFixedStack(FI), 142 MachineMemOperand::MOLoad, 0, 143 MFI.getObjectSize(FI), 144 MFI.getObjectAlignment(FI)); 145 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::tRestore), DestReg) 146 .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); 147 } 148} 149 150bool Thumb1InstrInfo:: 151spillCalleeSavedRegisters(MachineBasicBlock &MBB, 152 MachineBasicBlock::iterator MI, 153 const std::vector<CalleeSavedInfo> &CSI) const { 154 if (CSI.empty()) 155 return false; 156 157 DebugLoc DL; 158 if (MI != MBB.end()) DL = MI->getDebugLoc(); 159 160 MachineInstrBuilder MIB = BuildMI(MBB, MI, DL, get(ARM::tPUSH)); 161 AddDefaultPred(MIB); 162 for (unsigned i = CSI.size(); i != 0; --i) { 163 unsigned Reg = CSI[i-1].getReg(); 164 // Add the callee-saved register as live-in. It's killed at the spill. 165 MBB.addLiveIn(Reg); 166 MIB.addReg(Reg, RegState::Kill); 167 } 168 return true; 169} 170 171bool Thumb1InstrInfo:: 172restoreCalleeSavedRegisters(MachineBasicBlock &MBB, 173 MachineBasicBlock::iterator MI, 174 const std::vector<CalleeSavedInfo> &CSI) const { 175 MachineFunction &MF = *MBB.getParent(); 176 ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>(); 177 if (CSI.empty()) 178 return false; 179 180 bool isVarArg = AFI->getVarArgsRegSaveSize() > 0; 181 DebugLoc DL = MI->getDebugLoc(); 182 MachineInstrBuilder MIB = BuildMI(MF, DL, get(ARM::tPOP)); 183 AddDefaultPred(MIB); 184 185 bool NumRegs = false; 186 for (unsigned i = CSI.size(); i != 0; --i) { 187 unsigned Reg = CSI[i-1].getReg(); 188 if (Reg == ARM::LR) { 189 // Special epilogue for vararg functions. See emitEpilogue 190 if (isVarArg) 191 continue; 192 Reg = ARM::PC; 193 (*MIB).setDesc(get(ARM::tPOP_RET)); 194 MI = MBB.erase(MI); 195 } 196 MIB.addReg(Reg, getDefRegState(true)); 197 NumRegs = true; 198 } 199 200 // It's illegal to emit pop instruction without operands. 201 if (NumRegs) 202 MBB.insert(MI, &*MIB); 203 else 204 MF.DeleteMachineInstr(MIB); 205 206 return true; 207} 208 209MachineInstr *Thumb1InstrInfo:: 210foldMemoryOperandImpl(MachineFunction &MF, MachineInstr *MI, 211 const SmallVectorImpl<unsigned> &Ops, int FI) const { 212 if (Ops.size() != 1) return NULL; 213 214 unsigned OpNum = Ops[0]; 215 unsigned Opc = MI->getOpcode(); 216 MachineInstr *NewMI = NULL; 217 switch (Opc) { 218 default: break; 219 case ARM::tMOVr: 220 case ARM::tMOVtgpr2gpr: 221 case ARM::tMOVgpr2tgpr: 222 case ARM::tMOVgpr2gpr: { 223 if (OpNum == 0) { // move -> store 224 unsigned SrcReg = MI->getOperand(1).getReg(); 225 bool isKill = MI->getOperand(1).isKill(); 226 if (TargetRegisterInfo::isPhysicalRegister(SrcReg) && 227 !isARMLowRegister(SrcReg)) 228 // tSpill cannot take a high register operand. 229 break; 230 NewMI = AddDefaultPred(BuildMI(MF, MI->getDebugLoc(), get(ARM::tSpill)) 231 .addReg(SrcReg, getKillRegState(isKill)) 232 .addFrameIndex(FI).addImm(0)); 233 } else { // move -> load 234 unsigned DstReg = MI->getOperand(0).getReg(); 235 if (TargetRegisterInfo::isPhysicalRegister(DstReg) && 236 !isARMLowRegister(DstReg)) 237 // tRestore cannot target a high register operand. 238 break; 239 bool isDead = MI->getOperand(0).isDead(); 240 NewMI = AddDefaultPred(BuildMI(MF, MI->getDebugLoc(), get(ARM::tRestore)) 241 .addReg(DstReg, 242 RegState::Define | getDeadRegState(isDead)) 243 .addFrameIndex(FI).addImm(0)); 244 } 245 break; 246 } 247 } 248 249 return NewMI; 250} 251