1 //===-- PPCELFObjectWriter.cpp - PPC ELF Writer ---------------------------===// 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 #include "MCTargetDesc/PPCMCTargetDesc.h" 11 #include "MCTargetDesc/PPCFixupKinds.h" 12 #include "llvm/ADT/STLExtras.h" 13 #include "llvm/MC/MCELFObjectWriter.h" 14 #include "llvm/MC/MCExpr.h" 15 #include "llvm/MC/MCValue.h" 16 #include "llvm/Support/ErrorHandling.h" 17 18 using namespace llvm; 19 20 namespace { 21 class PPCELFObjectWriter : public MCELFObjectTargetWriter { 22 public: 23 PPCELFObjectWriter(bool Is64Bit, uint8_t OSABI); 24 25 virtual ~PPCELFObjectWriter(); 26 protected: 27 virtual unsigned getRelocTypeInner(const MCValue &Target, 28 const MCFixup &Fixup, 29 bool IsPCRel) const; 30 virtual unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup, 31 bool IsPCRel, bool IsRelocWithSymbol, 32 int64_t Addend) const; 33 virtual const MCSymbol *undefinedExplicitRelSym(const MCValue &Target, 34 const MCFixup &Fixup, 35 bool IsPCRel) const; 36 }; 37 } 38 39 PPCELFObjectWriter::PPCELFObjectWriter(bool Is64Bit, uint8_t OSABI) 40 : MCELFObjectTargetWriter(Is64Bit, OSABI, 41 Is64Bit ? ELF::EM_PPC64 : ELF::EM_PPC, 42 /*HasRelocationAddend*/ true) {} 43 44 PPCELFObjectWriter::~PPCELFObjectWriter() { 45 } 46 47 unsigned PPCELFObjectWriter::getRelocTypeInner(const MCValue &Target, 48 const MCFixup &Fixup, 49 bool IsPCRel) const 50 { 51 MCSymbolRefExpr::VariantKind Modifier = Target.isAbsolute() ? 52 MCSymbolRefExpr::VK_None : Target.getSymA()->getKind(); 53 54 // determine the type of the relocation 55 unsigned Type; 56 if (IsPCRel) { 57 switch ((unsigned)Fixup.getKind()) { 58 default: 59 llvm_unreachable("Unimplemented"); 60 case PPC::fixup_ppc_br24: 61 Type = ELF::R_PPC_REL24; 62 break; 63 case PPC::fixup_ppc_brcond14: 64 Type = ELF::R_PPC_REL14; 65 break; 66 case FK_Data_4: 67 case FK_PCRel_4: 68 Type = ELF::R_PPC_REL32; 69 break; 70 case FK_Data_8: 71 case FK_PCRel_8: 72 Type = ELF::R_PPC64_REL64; 73 break; 74 } 75 } else { 76 switch ((unsigned)Fixup.getKind()) { 77 default: llvm_unreachable("invalid fixup kind!"); 78 case PPC::fixup_ppc_br24: 79 Type = ELF::R_PPC_ADDR24; 80 break; 81 case PPC::fixup_ppc_brcond14: 82 Type = ELF::R_PPC_ADDR14; // XXX: or BRNTAKEN?_ 83 break; 84 case PPC::fixup_ppc_half16: 85 switch (Modifier) { 86 default: llvm_unreachable("Unsupported Modifier"); 87 case MCSymbolRefExpr::VK_None: 88 Type = ELF::R_PPC_ADDR16; 89 break; 90 case MCSymbolRefExpr::VK_PPC_LO: 91 Type = ELF::R_PPC_ADDR16_LO; 92 break; 93 case MCSymbolRefExpr::VK_PPC_HI: 94 Type = ELF::R_PPC_ADDR16_HI; 95 break; 96 case MCSymbolRefExpr::VK_PPC_HA: 97 Type = ELF::R_PPC_ADDR16_HA; 98 break; 99 case MCSymbolRefExpr::VK_PPC_TOC: 100 Type = ELF::R_PPC64_TOC16; 101 break; 102 case MCSymbolRefExpr::VK_PPC_TOC_LO: 103 Type = ELF::R_PPC64_TOC16_LO; 104 break; 105 case MCSymbolRefExpr::VK_PPC_TOC_HI: 106 Type = ELF::R_PPC64_TOC16_HI; 107 break; 108 case MCSymbolRefExpr::VK_PPC_TOC_HA: 109 Type = ELF::R_PPC64_TOC16_HA; 110 break; 111 case MCSymbolRefExpr::VK_PPC_TPREL_LO: 112 Type = ELF::R_PPC_TPREL16_LO; 113 break; 114 case MCSymbolRefExpr::VK_PPC_TPREL_HA: 115 Type = ELF::R_PPC_TPREL16_HA; 116 break; 117 case MCSymbolRefExpr::VK_PPC_DTPREL_LO: 118 Type = ELF::R_PPC64_DTPREL16_LO; 119 break; 120 case MCSymbolRefExpr::VK_PPC_DTPREL_HA: 121 Type = ELF::R_PPC64_DTPREL16_HA; 122 break; 123 case MCSymbolRefExpr::VK_PPC_GOT_TLSGD_LO: 124 Type = ELF::R_PPC64_GOT_TLSGD16_LO; 125 break; 126 case MCSymbolRefExpr::VK_PPC_GOT_TLSGD_HA: 127 Type = ELF::R_PPC64_GOT_TLSGD16_HA; 128 break; 129 case MCSymbolRefExpr::VK_PPC_GOT_TLSLD_LO: 130 Type = ELF::R_PPC64_GOT_TLSLD16_LO; 131 break; 132 case MCSymbolRefExpr::VK_PPC_GOT_TLSLD_HA: 133 Type = ELF::R_PPC64_GOT_TLSLD16_HA; 134 break; 135 case MCSymbolRefExpr::VK_PPC_GOT_TPREL_HA: 136 Type = ELF::R_PPC64_GOT_TPREL16_HA; 137 break; 138 } 139 break; 140 case PPC::fixup_ppc_half16ds: 141 switch (Modifier) { 142 default: llvm_unreachable("Unsupported Modifier"); 143 case MCSymbolRefExpr::VK_None: 144 Type = ELF::R_PPC64_ADDR16_DS; 145 break; 146 case MCSymbolRefExpr::VK_PPC_LO: 147 Type = ELF::R_PPC64_ADDR16_LO_DS; 148 break; 149 case MCSymbolRefExpr::VK_PPC_TOC: 150 Type = ELF::R_PPC64_TOC16_DS; 151 break; 152 case MCSymbolRefExpr::VK_PPC_TOC_LO: 153 Type = ELF::R_PPC64_TOC16_LO_DS; 154 break; 155 case MCSymbolRefExpr::VK_PPC_GOT_TPREL_LO: 156 Type = ELF::R_PPC64_GOT_TPREL16_LO_DS; 157 break; 158 } 159 break; 160 case PPC::fixup_ppc_tlsreg: 161 Type = ELF::R_PPC64_TLS; 162 break; 163 case PPC::fixup_ppc_nofixup: 164 switch (Modifier) { 165 default: llvm_unreachable("Unsupported Modifier"); 166 case MCSymbolRefExpr::VK_PPC_TLSGD: 167 Type = ELF::R_PPC64_TLSGD; 168 break; 169 case MCSymbolRefExpr::VK_PPC_TLSLD: 170 Type = ELF::R_PPC64_TLSLD; 171 break; 172 } 173 break; 174 case FK_Data_8: 175 switch (Modifier) { 176 default: llvm_unreachable("Unsupported Modifier"); 177 case MCSymbolRefExpr::VK_PPC_TOCBASE: 178 Type = ELF::R_PPC64_TOC; 179 break; 180 case MCSymbolRefExpr::VK_None: 181 Type = ELF::R_PPC64_ADDR64; 182 break; 183 } 184 break; 185 case FK_Data_4: 186 Type = ELF::R_PPC_ADDR32; 187 break; 188 case FK_Data_2: 189 Type = ELF::R_PPC_ADDR16; 190 break; 191 } 192 } 193 return Type; 194 } 195 196 unsigned PPCELFObjectWriter::GetRelocType(const MCValue &Target, 197 const MCFixup &Fixup, 198 bool IsPCRel, 199 bool IsRelocWithSymbol, 200 int64_t Addend) const { 201 return getRelocTypeInner(Target, Fixup, IsPCRel); 202 } 203 204 const MCSymbol *PPCELFObjectWriter::undefinedExplicitRelSym(const MCValue &Target, 205 const MCFixup &Fixup, 206 bool IsPCRel) const { 207 assert(Target.getSymA() && "SymA cannot be 0"); 208 const MCSymbol &Symbol = Target.getSymA()->getSymbol().AliasedSymbol(); 209 210 unsigned RelocType = getRelocTypeInner(Target, Fixup, IsPCRel); 211 212 // The .odp creation emits a relocation against the symbol ".TOC." which 213 // create a R_PPC64_TOC relocation. However the relocation symbol name 214 // in final object creation should be NULL, since the symbol does not 215 // really exist, it is just the reference to TOC base for the current 216 // object file. 217 bool EmitThisSym = RelocType != ELF::R_PPC64_TOC; 218 219 if (EmitThisSym && !Symbol.isTemporary()) 220 return &Symbol; 221 return NULL; 222 } 223 224 MCObjectWriter *llvm::createPPCELFObjectWriter(raw_ostream &OS, 225 bool Is64Bit, 226 uint8_t OSABI) { 227 MCELFObjectTargetWriter *MOTW = new PPCELFObjectWriter(Is64Bit, OSABI); 228 return createELFObjectWriter(MOTW, OS, /*IsLittleEndian=*/false); 229 } 230