1 //===-- PPCMCInstLower.cpp - Convert PPC MachineInstr to an MCInst --------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This file contains code to lower PPC MachineInstrs to their corresponding 10 // MCInst records. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "MCTargetDesc/PPCMCExpr.h" 15 #include "PPC.h" 16 #include "PPCSubtarget.h" 17 #include "llvm/ADT/SmallString.h" 18 #include "llvm/ADT/Twine.h" 19 #include "llvm/CodeGen/AsmPrinter.h" 20 #include "llvm/CodeGen/MachineFunction.h" 21 #include "llvm/CodeGen/MachineModuleInfoImpls.h" 22 #include "llvm/CodeGen/TargetLowering.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/TargetLoweringObjectFile.h" 30 using namespace llvm; 31 32 static MCSymbol *GetSymbolFromOperand(const MachineOperand &MO, 33 AsmPrinter &AP) { 34 const TargetMachine &TM = AP.TM; 35 Mangler &Mang = TM.getObjFileLowering()->getMangler(); 36 const DataLayout &DL = AP.getDataLayout(); 37 MCContext &Ctx = AP.OutContext; 38 39 SmallString<128> Name; 40 if (!MO.isGlobal()) { 41 assert(MO.isSymbol() && "Isn't a symbol reference"); 42 Mangler::getNameWithPrefix(Name, MO.getSymbolName(), DL); 43 } else { 44 const GlobalValue *GV = MO.getGlobal(); 45 TM.getNameWithPrefix(Name, GV, Mang); 46 } 47 48 MCSymbol *Sym = Ctx.getOrCreateSymbol(Name); 49 50 return Sym; 51 } 52 53 static MCOperand GetSymbolRef(const MachineOperand &MO, const MCSymbol *Symbol, 54 AsmPrinter &Printer) { 55 MCContext &Ctx = Printer.OutContext; 56 MCSymbolRefExpr::VariantKind RefKind = MCSymbolRefExpr::VK_None; 57 58 unsigned access = MO.getTargetFlags() & PPCII::MO_ACCESS_MASK; 59 60 switch (access) { 61 case PPCII::MO_TPREL_LO: 62 RefKind = MCSymbolRefExpr::VK_PPC_TPREL_LO; 63 break; 64 case PPCII::MO_TPREL_HA: 65 RefKind = MCSymbolRefExpr::VK_PPC_TPREL_HA; 66 break; 67 case PPCII::MO_DTPREL_LO: 68 RefKind = MCSymbolRefExpr::VK_PPC_DTPREL_LO; 69 break; 70 case PPCII::MO_TLSLD_LO: 71 RefKind = MCSymbolRefExpr::VK_PPC_GOT_TLSLD_LO; 72 break; 73 case PPCII::MO_TOC_LO: 74 RefKind = MCSymbolRefExpr::VK_PPC_TOC_LO; 75 break; 76 case PPCII::MO_TLS: 77 bool IsPCRel = (MO.getTargetFlags() & ~access) == PPCII::MO_PCREL_FLAG; 78 RefKind = IsPCRel ? MCSymbolRefExpr::VK_PPC_TLS_PCREL 79 : MCSymbolRefExpr::VK_PPC_TLS; 80 break; 81 } 82 83 if (MO.getTargetFlags() == PPCII::MO_PLT) 84 RefKind = MCSymbolRefExpr::VK_PLT; 85 else if (MO.getTargetFlags() == PPCII::MO_PCREL_FLAG) 86 RefKind = MCSymbolRefExpr::VK_PCREL; 87 else if (MO.getTargetFlags() == (PPCII::MO_PCREL_FLAG | PPCII::MO_GOT_FLAG)) 88 RefKind = MCSymbolRefExpr::VK_PPC_GOT_PCREL; 89 else if (MO.getTargetFlags() == (PPCII::MO_PCREL_FLAG | PPCII::MO_TPREL_FLAG)) 90 RefKind = MCSymbolRefExpr::VK_TPREL; 91 else if (MO.getTargetFlags() == PPCII::MO_GOT_TLSGD_PCREL_FLAG) 92 RefKind = MCSymbolRefExpr::VK_PPC_GOT_TLSGD_PCREL; 93 else if (MO.getTargetFlags() == PPCII::MO_GOT_TLSLD_PCREL_FLAG) 94 RefKind = MCSymbolRefExpr::VK_PPC_GOT_TLSLD_PCREL; 95 else if (MO.getTargetFlags() == PPCII::MO_GOT_TPREL_PCREL_FLAG) 96 RefKind = MCSymbolRefExpr::VK_PPC_GOT_TPREL_PCREL; 97 98 const MachineInstr *MI = MO.getParent(); 99 const MachineFunction *MF = MI->getMF(); 100 const Module *M = MF->getFunction().getParent(); 101 const PPCSubtarget *Subtarget = &(MF->getSubtarget<PPCSubtarget>()); 102 const TargetMachine &TM = Printer.TM; 103 104 unsigned MIOpcode = MI->getOpcode(); 105 assert((Subtarget->isUsingPCRelativeCalls() || MIOpcode != PPC::BL8_NOTOC) && 106 "BL8_NOTOC is only valid when using PC Relative Calls."); 107 if (Subtarget->isUsingPCRelativeCalls()) { 108 if (MIOpcode == PPC::TAILB || MIOpcode == PPC::TAILB8 || 109 MIOpcode == PPC::TCRETURNdi || MIOpcode == PPC::TCRETURNdi8 || 110 MIOpcode == PPC::BL8_NOTOC) { 111 RefKind = MCSymbolRefExpr::VK_PPC_NOTOC; 112 } 113 if (MO.getTargetFlags() == PPCII::MO_PCREL_OPT_FLAG) 114 RefKind = MCSymbolRefExpr::VK_PPC_PCREL_OPT; 115 } 116 117 const MCExpr *Expr = MCSymbolRefExpr::create(Symbol, RefKind, Ctx); 118 // If -msecure-plt -fPIC, add 32768 to symbol. 119 if (Subtarget->isSecurePlt() && TM.isPositionIndependent() && 120 M->getPICLevel() == PICLevel::BigPIC && 121 MO.getTargetFlags() == PPCII::MO_PLT) 122 Expr = 123 MCBinaryExpr::createAdd(Expr, MCConstantExpr::create(32768, Ctx), Ctx); 124 125 if (!MO.isJTI() && MO.getOffset()) 126 Expr = MCBinaryExpr::createAdd(Expr, 127 MCConstantExpr::create(MO.getOffset(), Ctx), 128 Ctx); 129 130 // Subtract off the PIC base if required. 131 if (MO.getTargetFlags() & PPCII::MO_PIC_FLAG) { 132 const MachineFunction *MF = MO.getParent()->getParent()->getParent(); 133 134 const MCExpr *PB = MCSymbolRefExpr::create(MF->getPICBaseSymbol(), Ctx); 135 Expr = MCBinaryExpr::createSub(Expr, PB, Ctx); 136 } 137 138 // Add ha16() / lo16() markers if required. 139 switch (access) { 140 case PPCII::MO_LO: 141 Expr = PPCMCExpr::createLo(Expr, Ctx); 142 break; 143 case PPCII::MO_HA: 144 Expr = PPCMCExpr::createHa(Expr, Ctx); 145 break; 146 } 147 148 return MCOperand::createExpr(Expr); 149 } 150 151 void llvm::LowerPPCMachineInstrToMCInst(const MachineInstr *MI, MCInst &OutMI, 152 AsmPrinter &AP) { 153 OutMI.setOpcode(MI->getOpcode()); 154 155 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { 156 MCOperand MCOp; 157 if (LowerPPCMachineOperandToMCOperand(MI->getOperand(i), MCOp, AP)) 158 OutMI.addOperand(MCOp); 159 } 160 } 161 162 bool llvm::LowerPPCMachineOperandToMCOperand(const MachineOperand &MO, 163 MCOperand &OutMO, AsmPrinter &AP) { 164 switch (MO.getType()) { 165 default: 166 llvm_unreachable("unknown operand type"); 167 case MachineOperand::MO_Register: 168 assert(!MO.getSubReg() && "Subregs should be eliminated!"); 169 assert(MO.getReg() > PPC::NoRegister && 170 MO.getReg() < PPC::NUM_TARGET_REGS && 171 "Invalid register for this target!"); 172 // Ignore all implicit register operands. 173 if (MO.isImplicit()) 174 return false; 175 OutMO = MCOperand::createReg(MO.getReg()); 176 return true; 177 case MachineOperand::MO_Immediate: 178 OutMO = MCOperand::createImm(MO.getImm()); 179 return true; 180 case MachineOperand::MO_MachineBasicBlock: 181 OutMO = MCOperand::createExpr( 182 MCSymbolRefExpr::create(MO.getMBB()->getSymbol(), AP.OutContext)); 183 return true; 184 case MachineOperand::MO_GlobalAddress: 185 case MachineOperand::MO_ExternalSymbol: 186 OutMO = GetSymbolRef(MO, GetSymbolFromOperand(MO, AP), AP); 187 return true; 188 case MachineOperand::MO_JumpTableIndex: 189 OutMO = GetSymbolRef(MO, AP.GetJTISymbol(MO.getIndex()), AP); 190 return true; 191 case MachineOperand::MO_ConstantPoolIndex: 192 OutMO = GetSymbolRef(MO, AP.GetCPISymbol(MO.getIndex()), AP); 193 return true; 194 case MachineOperand::MO_BlockAddress: 195 OutMO = 196 GetSymbolRef(MO, AP.GetBlockAddressSymbol(MO.getBlockAddress()), AP); 197 return true; 198 case MachineOperand::MO_MCSymbol: 199 OutMO = GetSymbolRef(MO, MO.getMCSymbol(), AP); 200 return true; 201 case MachineOperand::MO_RegisterMask: 202 return false; 203 } 204 } 205
Indexes created Tue Jun 09 00:24:00 UTC 2026