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 = AP.getDataLayout(); 42 MCContext &Ctx = AP.OutContext; 43 44 SmallString<128> Name; 45 StringRef Suffix; 46 if (MO.getTargetFlags() & PPCII::MO_NLP_FLAG) 47 Suffix = "$non_lazy_ptr"; 48 49 if (!Suffix.empty()) 50 Name += DL.getPrivateGlobalPrefix(); 51 52 if (!MO.isGlobal()) { 53 assert(MO.isSymbol() && "Isn't a symbol reference"); 54 Mangler::getNameWithPrefix(Name, MO.getSymbolName(), DL); 55 } else { 56 const GlobalValue *GV = MO.getGlobal(); 57 TM.getNameWithPrefix(Name, GV, *Mang); 58 } 59 60 Name += Suffix; 61 MCSymbol *Sym = Ctx.getOrCreateSymbol(Name); 62 63 // If the symbol reference is actually to a non_lazy_ptr, not to the symbol, 64 // then add the suffix. 65 if (MO.getTargetFlags() & PPCII::MO_NLP_FLAG) { 66 MachineModuleInfoMachO &MachO = getMachOMMI(AP); 67 68 MachineModuleInfoImpl::StubValueTy &StubSym = MachO.getGVStubEntry(Sym); 69 70 if (!StubSym.getPointer()) { 71 assert(MO.isGlobal() && "Extern symbol not handled yet"); 72 StubSym = MachineModuleInfoImpl:: 73 StubValueTy(AP.getSymbol(MO.getGlobal()), 74 !MO.getGlobal()->hasInternalLinkage()); 75 } 76 return Sym; 77 } 78 79 return Sym; 80 } 81 82 static MCOperand GetSymbolRef(const MachineOperand &MO, const MCSymbol *Symbol, 83 AsmPrinter &Printer, bool isDarwin) { 84 MCContext &Ctx = Printer.OutContext; 85 MCSymbolRefExpr::VariantKind RefKind = MCSymbolRefExpr::VK_None; 86 87 unsigned access = MO.getTargetFlags() & PPCII::MO_ACCESS_MASK; 88 89 switch (access) { 90 case PPCII::MO_TPREL_LO: 91 RefKind = MCSymbolRefExpr::VK_PPC_TPREL_LO; 92 break; 93 case PPCII::MO_TPREL_HA: 94 RefKind = MCSymbolRefExpr::VK_PPC_TPREL_HA; 95 break; 96 case PPCII::MO_DTPREL_LO: 97 RefKind = MCSymbolRefExpr::VK_PPC_DTPREL_LO; 98 break; 99 case PPCII::MO_TLSLD_LO: 100 RefKind = MCSymbolRefExpr::VK_PPC_GOT_TLSLD_LO; 101 break; 102 case PPCII::MO_TOC_LO: 103 RefKind = MCSymbolRefExpr::VK_PPC_TOC_LO; 104 break; 105 case PPCII::MO_TLS: 106 RefKind = MCSymbolRefExpr::VK_PPC_TLS; 107 break; 108 } 109 110 if (MO.getTargetFlags() == PPCII::MO_PLT) 111 RefKind = MCSymbolRefExpr::VK_PLT; 112 113 const MCExpr *Expr = MCSymbolRefExpr::create(Symbol, RefKind, Ctx); 114 115 if (!MO.isJTI() && MO.getOffset()) 116 Expr = MCBinaryExpr::createAdd(Expr, 117 MCConstantExpr::create(MO.getOffset(), Ctx), 118 Ctx); 119 120 // Subtract off the PIC base if required. 121 if (MO.getTargetFlags() & PPCII::MO_PIC_FLAG) { 122 const MachineFunction *MF = MO.getParent()->getParent()->getParent(); 123 124 const MCExpr *PB = MCSymbolRefExpr::create(MF->getPICBaseSymbol(), Ctx); 125 Expr = MCBinaryExpr::createSub(Expr, PB, Ctx); 126 } 127 128 // Add ha16() / lo16() markers if required. 129 switch (access) { 130 case PPCII::MO_LO: 131 Expr = PPCMCExpr::createLo(Expr, isDarwin, Ctx); 132 break; 133 case PPCII::MO_HA: 134 Expr = PPCMCExpr::createHa(Expr, isDarwin, Ctx); 135 break; 136 } 137 138 return MCOperand::createExpr(Expr); 139 } 140 141 void llvm::LowerPPCMachineInstrToMCInst(const MachineInstr *MI, MCInst &OutMI, 142 AsmPrinter &AP, bool isDarwin) { 143 OutMI.setOpcode(MI->getOpcode()); 144 145 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { 146 const MachineOperand &MO = MI->getOperand(i); 147 148 MCOperand MCOp; 149 switch (MO.getType()) { 150 default: 151 MI->dump(); 152 llvm_unreachable("unknown operand type"); 153 case MachineOperand::MO_Register: 154 assert(!MO.getSubReg() && "Subregs should be eliminated!"); 155 assert(MO.getReg() > PPC::NoRegister && 156 MO.getReg() < PPC::NUM_TARGET_REGS && 157 "Invalid register for this target!"); 158 MCOp = MCOperand::createReg(MO.getReg()); 159 break; 160 case MachineOperand::MO_Immediate: 161 MCOp = MCOperand::createImm(MO.getImm()); 162 break; 163 case MachineOperand::MO_MachineBasicBlock: 164 MCOp = MCOperand::createExpr(MCSymbolRefExpr::create( 165 MO.getMBB()->getSymbol(), AP.OutContext)); 166 break; 167 case MachineOperand::MO_GlobalAddress: 168 case MachineOperand::MO_ExternalSymbol: 169 MCOp = GetSymbolRef(MO, GetSymbolFromOperand(MO, AP), AP, isDarwin); 170 break; 171 case MachineOperand::MO_JumpTableIndex: 172 MCOp = GetSymbolRef(MO, AP.GetJTISymbol(MO.getIndex()), AP, isDarwin); 173 break; 174 case MachineOperand::MO_ConstantPoolIndex: 175 MCOp = GetSymbolRef(MO, AP.GetCPISymbol(MO.getIndex()), AP, isDarwin); 176 break; 177 case MachineOperand::MO_BlockAddress: 178 MCOp = GetSymbolRef(MO,AP.GetBlockAddressSymbol(MO.getBlockAddress()),AP, 179 isDarwin); 180 break; 181 case MachineOperand::MO_RegisterMask: 182 continue; 183 } 184 185 OutMI.addOperand(MCOp); 186 } 187 } 188