1 //===-- MipsMCInstLower.cpp - Convert Mips MachineInstr to MCInst ---------===// 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 code to lower Mips MachineInstrs to their corresponding 11 // MCInst records. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #include "MipsMCInstLower.h" 16 #include "MipsAsmPrinter.h" 17 #include "MipsInstrInfo.h" 18 #include "MCTargetDesc/MipsBaseInfo.h" 19 #include "llvm/CodeGen/MachineFunction.h" 20 #include "llvm/CodeGen/MachineInstr.h" 21 #include "llvm/CodeGen/MachineOperand.h" 22 #include "llvm/MC/MCContext.h" 23 #include "llvm/MC/MCExpr.h" 24 #include "llvm/MC/MCInst.h" 25 #include "llvm/Target/Mangler.h" 26 27 using namespace llvm; 28 29 MipsMCInstLower::MipsMCInstLower(MipsAsmPrinter &asmprinter) 30 : AsmPrinter(asmprinter) {} 31 32 void MipsMCInstLower::Initialize(Mangler *M, MCContext* C) { 33 Mang = M; 34 Ctx = C; 35 } 36 37 MCOperand MipsMCInstLower::LowerSymbolOperand(const MachineOperand &MO, 38 MachineOperandType MOTy, 39 unsigned Offset) const { 40 MCSymbolRefExpr::VariantKind Kind; 41 const MCSymbol *Symbol; 42 43 switch(MO.getTargetFlags()) { 44 default: llvm_unreachable("Invalid target flag!"); 45 case MipsII::MO_NO_FLAG: Kind = MCSymbolRefExpr::VK_None; break; 46 case MipsII::MO_GPREL: Kind = MCSymbolRefExpr::VK_Mips_GPREL; break; 47 case MipsII::MO_GOT_CALL: Kind = MCSymbolRefExpr::VK_Mips_GOT_CALL; break; 48 case MipsII::MO_GOT16: Kind = MCSymbolRefExpr::VK_Mips_GOT16; break; 49 case MipsII::MO_GOT: Kind = MCSymbolRefExpr::VK_Mips_GOT; break; 50 case MipsII::MO_ABS_HI: Kind = MCSymbolRefExpr::VK_Mips_ABS_HI; break; 51 case MipsII::MO_ABS_LO: Kind = MCSymbolRefExpr::VK_Mips_ABS_LO; break; 52 case MipsII::MO_TLSGD: Kind = MCSymbolRefExpr::VK_Mips_TLSGD; break; 53 case MipsII::MO_TLSLDM: Kind = MCSymbolRefExpr::VK_Mips_TLSLDM; break; 54 case MipsII::MO_DTPREL_HI: Kind = MCSymbolRefExpr::VK_Mips_DTPREL_HI; break; 55 case MipsII::MO_DTPREL_LO: Kind = MCSymbolRefExpr::VK_Mips_DTPREL_LO; break; 56 case MipsII::MO_GOTTPREL: Kind = MCSymbolRefExpr::VK_Mips_GOTTPREL; break; 57 case MipsII::MO_TPREL_HI: Kind = MCSymbolRefExpr::VK_Mips_TPREL_HI; break; 58 case MipsII::MO_TPREL_LO: Kind = MCSymbolRefExpr::VK_Mips_TPREL_LO; break; 59 case MipsII::MO_GPOFF_HI: Kind = MCSymbolRefExpr::VK_Mips_GPOFF_HI; break; 60 case MipsII::MO_GPOFF_LO: Kind = MCSymbolRefExpr::VK_Mips_GPOFF_LO; break; 61 case MipsII::MO_GOT_DISP: Kind = MCSymbolRefExpr::VK_Mips_GOT_DISP; break; 62 case MipsII::MO_GOT_PAGE: Kind = MCSymbolRefExpr::VK_Mips_GOT_PAGE; break; 63 case MipsII::MO_GOT_OFST: Kind = MCSymbolRefExpr::VK_Mips_GOT_OFST; break; 64 } 65 66 switch (MOTy) { 67 case MachineOperand::MO_MachineBasicBlock: 68 Symbol = MO.getMBB()->getSymbol(); 69 break; 70 71 case MachineOperand::MO_GlobalAddress: 72 Symbol = Mang->getSymbol(MO.getGlobal()); 73 Offset += MO.getOffset(); 74 break; 75 76 case MachineOperand::MO_BlockAddress: 77 Symbol = AsmPrinter.GetBlockAddressSymbol(MO.getBlockAddress()); 78 Offset += MO.getOffset(); 79 break; 80 81 case MachineOperand::MO_ExternalSymbol: 82 Symbol = AsmPrinter.GetExternalSymbolSymbol(MO.getSymbolName()); 83 Offset += MO.getOffset(); 84 break; 85 86 case MachineOperand::MO_JumpTableIndex: 87 Symbol = AsmPrinter.GetJTISymbol(MO.getIndex()); 88 break; 89 90 case MachineOperand::MO_ConstantPoolIndex: 91 Symbol = AsmPrinter.GetCPISymbol(MO.getIndex()); 92 Offset += MO.getOffset(); 93 break; 94 95 default: 96 llvm_unreachable("<unknown operand type>"); 97 } 98 99 const MCSymbolRefExpr *MCSym = MCSymbolRefExpr::Create(Symbol, Kind, *Ctx); 100 101 if (!Offset) 102 return MCOperand::CreateExpr(MCSym); 103 104 // Assume offset is never negative. 105 assert(Offset > 0); 106 107 const MCConstantExpr *OffsetExpr = MCConstantExpr::Create(Offset, *Ctx); 108 const MCBinaryExpr *AddExpr = MCBinaryExpr::CreateAdd(MCSym, OffsetExpr, *Ctx); 109 return MCOperand::CreateExpr(AddExpr); 110 } 111 112 static void CreateMCInst(MCInst& Inst, unsigned Opc, const MCOperand& Opnd0, 113 const MCOperand& Opnd1, 114 const MCOperand& Opnd2 = MCOperand()) { 115 Inst.setOpcode(Opc); 116 Inst.addOperand(Opnd0); 117 Inst.addOperand(Opnd1); 118 if (Opnd2.isValid()) 119 Inst.addOperand(Opnd2); 120 } 121 122 MCOperand MipsMCInstLower::LowerOperand(const MachineOperand& MO, 123 unsigned offset) const { 124 MachineOperandType MOTy = MO.getType(); 125 126 switch (MOTy) { 127 default: llvm_unreachable("unknown operand type"); 128 case MachineOperand::MO_Register: 129 // Ignore all implicit register operands. 130 if (MO.isImplicit()) break; 131 return MCOperand::CreateReg(MO.getReg()); 132 case MachineOperand::MO_Immediate: 133 return MCOperand::CreateImm(MO.getImm() + offset); 134 case MachineOperand::MO_MachineBasicBlock: 135 case MachineOperand::MO_GlobalAddress: 136 case MachineOperand::MO_ExternalSymbol: 137 case MachineOperand::MO_JumpTableIndex: 138 case MachineOperand::MO_ConstantPoolIndex: 139 case MachineOperand::MO_BlockAddress: 140 return LowerSymbolOperand(MO, MOTy, offset); 141 case MachineOperand::MO_RegisterMask: 142 break; 143 } 144 145 return MCOperand(); 146 } 147 148 void MipsMCInstLower::Lower(const MachineInstr *MI, MCInst &OutMI) const { 149 OutMI.setOpcode(MI->getOpcode()); 150 151 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { 152 const MachineOperand &MO = MI->getOperand(i); 153 MCOperand MCOp = LowerOperand(MO); 154 155 if (MCOp.isValid()) 156 OutMI.addOperand(MCOp); 157 } 158 } 159 160 // Create the following two instructions: 161 // "lui $2, %hi(_gp_disp)" 162 // "addiu $2, $2, %lo(_gp_disp)" 163 void MipsMCInstLower::LowerSETGP01(SmallVector<MCInst, 4>& MCInsts) { 164 MCOperand RegOpnd = MCOperand::CreateReg(Mips::V0); 165 StringRef SymName("_gp_disp"); 166 const MCSymbol *Sym = Ctx->GetOrCreateSymbol(SymName); 167 const MCSymbolRefExpr *MCSym; 168 169 MCSym = MCSymbolRefExpr::Create(Sym, MCSymbolRefExpr::VK_Mips_ABS_HI, *Ctx); 170 MCOperand SymHi = MCOperand::CreateExpr(MCSym); 171 MCSym = MCSymbolRefExpr::Create(Sym, MCSymbolRefExpr::VK_Mips_ABS_LO, *Ctx); 172 MCOperand SymLo = MCOperand::CreateExpr(MCSym); 173 174 MCInsts.resize(2); 175 176 CreateMCInst(MCInsts[0], Mips::LUi, RegOpnd, SymHi); 177 CreateMCInst(MCInsts[1], Mips::ADDiu, RegOpnd, RegOpnd, SymLo); 178 } 179