1 //===-- PPCMCInstLower.cpp - Convert PPC MachineInstr to an 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 PPC MachineInstrs to their corresponding 11 // MCInst records. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #include "PPC.h" 16 #include "MCTargetDesc/PPCMCExpr.h" 17 #include "PPCSubtarget.h" 18 #include "llvm/ADT/SmallString.h" 19 #include "llvm/ADT/Twine.h" 20 #include "llvm/CodeGen/AsmPrinter.h" 21 #include "llvm/CodeGen/MachineFunction.h" 22 #include "llvm/CodeGen/MachineModuleInfoImpls.h" 23 #include "llvm/IR/DataLayout.h" 24 #include "llvm/IR/GlobalValue.h" 25 #include "llvm/IR/Mangler.h" 26 #include "llvm/MC/MCAsmInfo.h" 27 #include "llvm/MC/MCExpr.h" 28 #include "llvm/MC/MCInst.h" 29 #include "llvm/Target/TargetLowering.h" 30 #include "llvm/Target/TargetLoweringObjectFile.h" 31 using namespace llvm; 32 33 static MachineModuleInfoMachO &getMachOMMI(AsmPrinter &AP) { 34 return AP.MMI->getObjFileInfo<MachineModuleInfoMachO>(); 35 } 36 37 38 static MCSymbol *GetSymbolFromOperand(const MachineOperand &MO, AsmPrinter &AP){ 39 const TargetMachine &TM = AP.TM; 40 Mangler *Mang = AP.Mang; 41 const DataLayout *DL = TM.getDataLayout(); 42 MCContext &Ctx = AP.OutContext; 43 bool isDarwin = Triple(TM.getTargetTriple()).isOSDarwin(); 44 45 SmallString<128> Name; 46 StringRef Suffix; 47 if (MO.getTargetFlags() == PPCII::MO_PLT_OR_STUB) { 48 if (isDarwin) 49 Suffix = "$stub"; 50 } else if (MO.getTargetFlags() & PPCII::MO_NLP_FLAG) 51 Suffix = "$non_lazy_ptr"; 52 53 if (!Suffix.empty()) 54 Name += DL->getPrivateGlobalPrefix(); 55 56 unsigned PrefixLen = Name.size(); 57 58 if (!MO.isGlobal()) { 59 assert(MO.isSymbol() && "Isn't a symbol reference"); 60 Mang->getNameWithPrefix(Name, MO.getSymbolName()); 61 } else { 62 const GlobalValue *GV = MO.getGlobal(); 63 TM.getNameWithPrefix(Name, GV, *Mang); 64 } 65 66 unsigned OrigLen = Name.size() - PrefixLen; 67 68 Name += Suffix; 69 MCSymbol *Sym = Ctx.GetOrCreateSymbol(Name.str()); 70 StringRef OrigName = StringRef(Name).substr(PrefixLen, OrigLen); 71 72 // If the target flags on the operand changes the name of the symbol, do that 73 // before we return the symbol. 74 if (MO.getTargetFlags() == PPCII::MO_PLT_OR_STUB && isDarwin) { 75 MachineModuleInfoImpl::StubValueTy &StubSym = 76 getMachOMMI(AP).getFnStubEntry(Sym); 77 if (StubSym.getPointer()) 78 return Sym; 79 80 if (MO.isGlobal()) { 81 StubSym = 82 MachineModuleInfoImpl:: 83 StubValueTy(AP.getSymbol(MO.getGlobal()), 84 !MO.getGlobal()->hasInternalLinkage()); 85 } else { 86 StubSym = 87 MachineModuleInfoImpl:: 88 StubValueTy(Ctx.GetOrCreateSymbol(OrigName), false); 89 } 90 return Sym; 91 } 92 93 // If the symbol reference is actually to a non_lazy_ptr, not to the symbol, 94 // then add the suffix. 95 if (MO.getTargetFlags() & PPCII::MO_NLP_FLAG) { 96 MachineModuleInfoMachO &MachO = getMachOMMI(AP); 97 98 MachineModuleInfoImpl::StubValueTy &StubSym = 99 (MO.getTargetFlags() & PPCII::MO_NLP_HIDDEN_FLAG) ? 100 MachO.getHiddenGVStubEntry(Sym) : MachO.getGVStubEntry(Sym); 101 102 if (!StubSym.getPointer()) { 103 assert(MO.isGlobal() && "Extern symbol not handled yet"); 104 StubSym = MachineModuleInfoImpl:: 105 StubValueTy(AP.getSymbol(MO.getGlobal()), 106 !MO.getGlobal()->hasInternalLinkage()); 107 } 108 return Sym; 109 } 110 111 return Sym; 112 } 113 114 static MCOperand GetSymbolRef(const MachineOperand &MO, const MCSymbol *Symbol, 115 AsmPrinter &Printer, bool isDarwin) { 116 MCContext &Ctx = Printer.OutContext; 117 MCSymbolRefExpr::VariantKind RefKind = MCSymbolRefExpr::VK_None; 118 119 unsigned access = MO.getTargetFlags() & PPCII::MO_ACCESS_MASK; 120 121 switch (access) { 122 case PPCII::MO_TPREL_LO: 123 RefKind = MCSymbolRefExpr::VK_PPC_TPREL_LO; 124 break; 125 case PPCII::MO_TPREL_HA: 126 RefKind = MCSymbolRefExpr::VK_PPC_TPREL_HA; 127 break; 128 case PPCII::MO_DTPREL_LO: 129 RefKind = MCSymbolRefExpr::VK_PPC_DTPREL_LO; 130 break; 131 case PPCII::MO_TLSLD_LO: 132 RefKind = MCSymbolRefExpr::VK_PPC_GOT_TLSLD_LO; 133 break; 134 case PPCII::MO_TOC_LO: 135 RefKind = MCSymbolRefExpr::VK_PPC_TOC_LO; 136 break; 137 case PPCII::MO_TLS: 138 RefKind = MCSymbolRefExpr::VK_PPC_TLS; 139 break; 140 case PPCII::MO_TLSGD: 141 RefKind = MCSymbolRefExpr::VK_PPC_TLSGD; 142 break; 143 case PPCII::MO_TLSLD: 144 RefKind = MCSymbolRefExpr::VK_PPC_TLSLD; 145 break; 146 } 147 148 if (MO.getTargetFlags() == PPCII::MO_PLT_OR_STUB && !isDarwin) 149 RefKind = MCSymbolRefExpr::VK_PLT; 150 151 const MCExpr *Expr = MCSymbolRefExpr::Create(Symbol, RefKind, Ctx); 152 153 if (!MO.isJTI() && MO.getOffset()) 154 Expr = MCBinaryExpr::CreateAdd(Expr, 155 MCConstantExpr::Create(MO.getOffset(), Ctx), 156 Ctx); 157 158 // Subtract off the PIC base if required. 159 if (MO.getTargetFlags() & PPCII::MO_PIC_FLAG) { 160 const MachineFunction *MF = MO.getParent()->getParent()->getParent(); 161 162 const MCExpr *PB = MCSymbolRefExpr::Create(MF->getPICBaseSymbol(), Ctx); 163 Expr = MCBinaryExpr::CreateSub(Expr, PB, Ctx); 164 } 165 166 // Add ha16() / lo16() markers if required. 167 switch (access) { 168 case PPCII::MO_LO: 169 Expr = PPCMCExpr::CreateLo(Expr, isDarwin, Ctx); 170 break; 171 case PPCII::MO_HA: 172 Expr = PPCMCExpr::CreateHa(Expr, isDarwin, Ctx); 173 break; 174 } 175 176 return MCOperand::CreateExpr(Expr); 177 } 178 179 void llvm::LowerPPCMachineInstrToMCInst(const MachineInstr *MI, MCInst &OutMI, 180 AsmPrinter &AP, bool isDarwin) { 181 OutMI.setOpcode(MI->getOpcode()); 182 183 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { 184 const MachineOperand &MO = MI->getOperand(i); 185 186 MCOperand MCOp; 187 switch (MO.getType()) { 188 default: 189 MI->dump(); 190 llvm_unreachable("unknown operand type"); 191 case MachineOperand::MO_Register: 192 assert(!MO.getSubReg() && "Subregs should be eliminated!"); 193 MCOp = MCOperand::CreateReg(MO.getReg()); 194 break; 195 case MachineOperand::MO_Immediate: 196 MCOp = MCOperand::CreateImm(MO.getImm()); 197 break; 198 case MachineOperand::MO_MachineBasicBlock: 199 MCOp = MCOperand::CreateExpr(MCSymbolRefExpr::Create( 200 MO.getMBB()->getSymbol(), AP.OutContext)); 201 break; 202 case MachineOperand::MO_GlobalAddress: 203 case MachineOperand::MO_ExternalSymbol: 204 MCOp = GetSymbolRef(MO, GetSymbolFromOperand(MO, AP), AP, isDarwin); 205 break; 206 case MachineOperand::MO_JumpTableIndex: 207 MCOp = GetSymbolRef(MO, AP.GetJTISymbol(MO.getIndex()), AP, isDarwin); 208 break; 209 case MachineOperand::MO_ConstantPoolIndex: 210 MCOp = GetSymbolRef(MO, AP.GetCPISymbol(MO.getIndex()), AP, isDarwin); 211 break; 212 case MachineOperand::MO_BlockAddress: 213 MCOp = GetSymbolRef(MO,AP.GetBlockAddressSymbol(MO.getBlockAddress()),AP, 214 isDarwin); 215 break; 216 case MachineOperand::MO_RegisterMask: 217 continue; 218 } 219 220 OutMI.addOperand(MCOp); 221 } 222 } 223