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 *ExplicitRelSym(const MCAssembler &Asm, 34 const MCValue &Target, 35 const MCFragment &F, 36 const MCFixup &Fixup, 37 bool IsPCRel) const; 38 virtual const MCSymbol *undefinedExplicitRelSym(const MCValue &Target, 39 const MCFixup &Fixup, 40 bool IsPCRel) const; 41 }; 42 } 43 44 PPCELFObjectWriter::PPCELFObjectWriter(bool Is64Bit, uint8_t OSABI) 45 : MCELFObjectTargetWriter(Is64Bit, OSABI, 46 Is64Bit ? ELF::EM_PPC64 : ELF::EM_PPC, 47 /*HasRelocationAddend*/ true) {} 48 49 PPCELFObjectWriter::~PPCELFObjectWriter() { 50 } 51 52 unsigned PPCELFObjectWriter::getRelocTypeInner(const MCValue &Target, 53 const MCFixup &Fixup, 54 bool IsPCRel) const 55 { 56 MCSymbolRefExpr::VariantKind Modifier = Target.isAbsolute() ? 57 MCSymbolRefExpr::VK_None : Target.getSymA()->getKind(); 58 59 // determine the type of the relocation 60 unsigned Type; 61 if (IsPCRel) { 62 switch ((unsigned)Fixup.getKind()) { 63 default: 64 llvm_unreachable("Unimplemented"); 65 case PPC::fixup_ppc_br24: 66 case PPC::fixup_ppc_br24abs: 67 Type = ELF::R_PPC_REL24; 68 break; 69 case PPC::fixup_ppc_brcond14: 70 case PPC::fixup_ppc_brcond14abs: 71 Type = ELF::R_PPC_REL14; 72 break; 73 case PPC::fixup_ppc_half16: 74 switch (Modifier) { 75 default: llvm_unreachable("Unsupported Modifier"); 76 case MCSymbolRefExpr::VK_None: 77 Type = ELF::R_PPC_REL16; 78 break; 79 case MCSymbolRefExpr::VK_PPC_LO: 80 Type = ELF::R_PPC_REL16_LO; 81 break; 82 case MCSymbolRefExpr::VK_PPC_HI: 83 Type = ELF::R_PPC_REL16_HI; 84 break; 85 case MCSymbolRefExpr::VK_PPC_HA: 86 Type = ELF::R_PPC_REL16_HA; 87 break; 88 } 89 break; 90 case FK_Data_4: 91 case FK_PCRel_4: 92 Type = ELF::R_PPC_REL32; 93 break; 94 case FK_Data_8: 95 case FK_PCRel_8: 96 Type = ELF::R_PPC64_REL64; 97 break; 98 } 99 } else { 100 switch ((unsigned)Fixup.getKind()) { 101 default: llvm_unreachable("invalid fixup kind!"); 102 case PPC::fixup_ppc_br24abs: 103 Type = ELF::R_PPC_ADDR24; 104 break; 105 case PPC::fixup_ppc_brcond14abs: 106 Type = ELF::R_PPC_ADDR14; // XXX: or BRNTAKEN?_ 107 break; 108 case PPC::fixup_ppc_half16: 109 switch (Modifier) { 110 default: llvm_unreachable("Unsupported Modifier"); 111 case MCSymbolRefExpr::VK_None: 112 Type = ELF::R_PPC_ADDR16; 113 break; 114 case MCSymbolRefExpr::VK_PPC_LO: 115 Type = ELF::R_PPC_ADDR16_LO; 116 break; 117 case MCSymbolRefExpr::VK_PPC_HI: 118 Type = ELF::R_PPC_ADDR16_HI; 119 break; 120 case MCSymbolRefExpr::VK_PPC_HA: 121 Type = ELF::R_PPC_ADDR16_HA; 122 break; 123 case MCSymbolRefExpr::VK_PPC_HIGHER: 124 Type = ELF::R_PPC64_ADDR16_HIGHER; 125 break; 126 case MCSymbolRefExpr::VK_PPC_HIGHERA: 127 Type = ELF::R_PPC64_ADDR16_HIGHERA; 128 break; 129 case MCSymbolRefExpr::VK_PPC_HIGHEST: 130 Type = ELF::R_PPC64_ADDR16_HIGHEST; 131 break; 132 case MCSymbolRefExpr::VK_PPC_HIGHESTA: 133 Type = ELF::R_PPC64_ADDR16_HIGHESTA; 134 break; 135 case MCSymbolRefExpr::VK_GOT: 136 Type = ELF::R_PPC_GOT16; 137 break; 138 case MCSymbolRefExpr::VK_PPC_GOT_LO: 139 Type = ELF::R_PPC_GOT16_LO; 140 break; 141 case MCSymbolRefExpr::VK_PPC_GOT_HI: 142 Type = ELF::R_PPC_GOT16_HI; 143 break; 144 case MCSymbolRefExpr::VK_PPC_GOT_HA: 145 Type = ELF::R_PPC_GOT16_HA; 146 break; 147 case MCSymbolRefExpr::VK_PPC_TOC: 148 Type = ELF::R_PPC64_TOC16; 149 break; 150 case MCSymbolRefExpr::VK_PPC_TOC_LO: 151 Type = ELF::R_PPC64_TOC16_LO; 152 break; 153 case MCSymbolRefExpr::VK_PPC_TOC_HI: 154 Type = ELF::R_PPC64_TOC16_HI; 155 break; 156 case MCSymbolRefExpr::VK_PPC_TOC_HA: 157 Type = ELF::R_PPC64_TOC16_HA; 158 break; 159 case MCSymbolRefExpr::VK_PPC_TPREL: 160 Type = ELF::R_PPC_TPREL16; 161 break; 162 case MCSymbolRefExpr::VK_PPC_TPREL_LO: 163 Type = ELF::R_PPC_TPREL16_LO; 164 break; 165 case MCSymbolRefExpr::VK_PPC_TPREL_HI: 166 Type = ELF::R_PPC_TPREL16_HI; 167 break; 168 case MCSymbolRefExpr::VK_PPC_TPREL_HA: 169 Type = ELF::R_PPC_TPREL16_HA; 170 break; 171 case MCSymbolRefExpr::VK_PPC_TPREL_HIGHER: 172 Type = ELF::R_PPC64_TPREL16_HIGHER; 173 break; 174 case MCSymbolRefExpr::VK_PPC_TPREL_HIGHERA: 175 Type = ELF::R_PPC64_TPREL16_HIGHERA; 176 break; 177 case MCSymbolRefExpr::VK_PPC_TPREL_HIGHEST: 178 Type = ELF::R_PPC64_TPREL16_HIGHEST; 179 break; 180 case MCSymbolRefExpr::VK_PPC_TPREL_HIGHESTA: 181 Type = ELF::R_PPC64_TPREL16_HIGHESTA; 182 break; 183 case MCSymbolRefExpr::VK_PPC_DTPREL: 184 Type = ELF::R_PPC64_DTPREL16; 185 break; 186 case MCSymbolRefExpr::VK_PPC_DTPREL_LO: 187 Type = ELF::R_PPC64_DTPREL16_LO; 188 break; 189 case MCSymbolRefExpr::VK_PPC_DTPREL_HI: 190 Type = ELF::R_PPC64_DTPREL16_HI; 191 break; 192 case MCSymbolRefExpr::VK_PPC_DTPREL_HA: 193 Type = ELF::R_PPC64_DTPREL16_HA; 194 break; 195 case MCSymbolRefExpr::VK_PPC_DTPREL_HIGHER: 196 Type = ELF::R_PPC64_DTPREL16_HIGHER; 197 break; 198 case MCSymbolRefExpr::VK_PPC_DTPREL_HIGHERA: 199 Type = ELF::R_PPC64_DTPREL16_HIGHERA; 200 break; 201 case MCSymbolRefExpr::VK_PPC_DTPREL_HIGHEST: 202 Type = ELF::R_PPC64_DTPREL16_HIGHEST; 203 break; 204 case MCSymbolRefExpr::VK_PPC_DTPREL_HIGHESTA: 205 Type = ELF::R_PPC64_DTPREL16_HIGHESTA; 206 break; 207 case MCSymbolRefExpr::VK_PPC_GOT_TLSGD: 208 Type = ELF::R_PPC64_GOT_TLSGD16; 209 break; 210 case MCSymbolRefExpr::VK_PPC_GOT_TLSGD_LO: 211 Type = ELF::R_PPC64_GOT_TLSGD16_LO; 212 break; 213 case MCSymbolRefExpr::VK_PPC_GOT_TLSGD_HI: 214 Type = ELF::R_PPC64_GOT_TLSGD16_HI; 215 break; 216 case MCSymbolRefExpr::VK_PPC_GOT_TLSGD_HA: 217 Type = ELF::R_PPC64_GOT_TLSGD16_HA; 218 break; 219 case MCSymbolRefExpr::VK_PPC_GOT_TLSLD: 220 Type = ELF::R_PPC64_GOT_TLSLD16; 221 break; 222 case MCSymbolRefExpr::VK_PPC_GOT_TLSLD_LO: 223 Type = ELF::R_PPC64_GOT_TLSLD16_LO; 224 break; 225 case MCSymbolRefExpr::VK_PPC_GOT_TLSLD_HI: 226 Type = ELF::R_PPC64_GOT_TLSLD16_HI; 227 break; 228 case MCSymbolRefExpr::VK_PPC_GOT_TLSLD_HA: 229 Type = ELF::R_PPC64_GOT_TLSLD16_HA; 230 break; 231 case MCSymbolRefExpr::VK_PPC_GOT_TPREL_HI: 232 Type = ELF::R_PPC64_GOT_TPREL16_HI; 233 break; 234 case MCSymbolRefExpr::VK_PPC_GOT_TPREL_HA: 235 Type = ELF::R_PPC64_GOT_TPREL16_HA; 236 break; 237 case MCSymbolRefExpr::VK_PPC_GOT_DTPREL_HI: 238 Type = ELF::R_PPC64_GOT_DTPREL16_HI; 239 break; 240 case MCSymbolRefExpr::VK_PPC_GOT_DTPREL_HA: 241 Type = ELF::R_PPC64_GOT_DTPREL16_HA; 242 break; 243 } 244 break; 245 case PPC::fixup_ppc_half16ds: 246 switch (Modifier) { 247 default: llvm_unreachable("Unsupported Modifier"); 248 case MCSymbolRefExpr::VK_None: 249 Type = ELF::R_PPC64_ADDR16_DS; 250 break; 251 case MCSymbolRefExpr::VK_PPC_LO: 252 Type = ELF::R_PPC64_ADDR16_LO_DS; 253 break; 254 case MCSymbolRefExpr::VK_GOT: 255 Type = ELF::R_PPC64_GOT16_DS; 256 break; 257 case MCSymbolRefExpr::VK_PPC_GOT_LO: 258 Type = ELF::R_PPC64_GOT16_LO_DS; 259 break; 260 case MCSymbolRefExpr::VK_PPC_TOC: 261 Type = ELF::R_PPC64_TOC16_DS; 262 break; 263 case MCSymbolRefExpr::VK_PPC_TOC_LO: 264 Type = ELF::R_PPC64_TOC16_LO_DS; 265 break; 266 case MCSymbolRefExpr::VK_PPC_TPREL: 267 Type = ELF::R_PPC64_TPREL16_DS; 268 break; 269 case MCSymbolRefExpr::VK_PPC_TPREL_LO: 270 Type = ELF::R_PPC64_TPREL16_LO_DS; 271 break; 272 case MCSymbolRefExpr::VK_PPC_DTPREL: 273 Type = ELF::R_PPC64_DTPREL16_DS; 274 break; 275 case MCSymbolRefExpr::VK_PPC_DTPREL_LO: 276 Type = ELF::R_PPC64_DTPREL16_LO_DS; 277 break; 278 case MCSymbolRefExpr::VK_PPC_GOT_TPREL: 279 Type = ELF::R_PPC64_GOT_TPREL16_DS; 280 break; 281 case MCSymbolRefExpr::VK_PPC_GOT_TPREL_LO: 282 Type = ELF::R_PPC64_GOT_TPREL16_LO_DS; 283 break; 284 case MCSymbolRefExpr::VK_PPC_GOT_DTPREL: 285 Type = ELF::R_PPC64_GOT_DTPREL16_DS; 286 break; 287 case MCSymbolRefExpr::VK_PPC_GOT_DTPREL_LO: 288 Type = ELF::R_PPC64_GOT_DTPREL16_LO_DS; 289 break; 290 } 291 break; 292 case PPC::fixup_ppc_tlsreg: 293 Type = ELF::R_PPC64_TLS; 294 break; 295 case PPC::fixup_ppc_nofixup: 296 switch (Modifier) { 297 default: llvm_unreachable("Unsupported Modifier"); 298 case MCSymbolRefExpr::VK_PPC_TLSGD: 299 Type = ELF::R_PPC64_TLSGD; 300 break; 301 case MCSymbolRefExpr::VK_PPC_TLSLD: 302 Type = ELF::R_PPC64_TLSLD; 303 break; 304 } 305 break; 306 case FK_Data_8: 307 switch (Modifier) { 308 default: llvm_unreachable("Unsupported Modifier"); 309 case MCSymbolRefExpr::VK_PPC_TOCBASE: 310 Type = ELF::R_PPC64_TOC; 311 break; 312 case MCSymbolRefExpr::VK_None: 313 Type = ELF::R_PPC64_ADDR64; 314 break; 315 case MCSymbolRefExpr::VK_PPC_DTPMOD: 316 Type = ELF::R_PPC64_DTPMOD64; 317 break; 318 case MCSymbolRefExpr::VK_PPC_TPREL: 319 Type = ELF::R_PPC64_TPREL64; 320 break; 321 case MCSymbolRefExpr::VK_PPC_DTPREL: 322 Type = ELF::R_PPC64_DTPREL64; 323 break; 324 } 325 break; 326 case FK_Data_4: 327 Type = ELF::R_PPC_ADDR32; 328 break; 329 case FK_Data_2: 330 Type = ELF::R_PPC_ADDR16; 331 break; 332 } 333 } 334 return Type; 335 } 336 337 unsigned PPCELFObjectWriter::GetRelocType(const MCValue &Target, 338 const MCFixup &Fixup, 339 bool IsPCRel, 340 bool IsRelocWithSymbol, 341 int64_t Addend) const { 342 return getRelocTypeInner(Target, Fixup, IsPCRel); 343 } 344 345 const MCSymbol *PPCELFObjectWriter::ExplicitRelSym(const MCAssembler &Asm, 346 const MCValue &Target, 347 const MCFragment &F, 348 const MCFixup &Fixup, 349 bool IsPCRel) const { 350 assert(Target.getSymA() && "SymA cannot be 0"); 351 MCSymbolRefExpr::VariantKind Modifier = Target.isAbsolute() ? 352 MCSymbolRefExpr::VK_None : Target.getSymA()->getKind(); 353 354 bool EmitThisSym; 355 switch (Modifier) { 356 // GOT references always need a relocation, even if the 357 // target symbol is local. 358 case MCSymbolRefExpr::VK_GOT: 359 case MCSymbolRefExpr::VK_PPC_GOT_LO: 360 case MCSymbolRefExpr::VK_PPC_GOT_HI: 361 case MCSymbolRefExpr::VK_PPC_GOT_HA: 362 EmitThisSym = true; 363 break; 364 default: 365 EmitThisSym = false; 366 break; 367 } 368 369 if (EmitThisSym) 370 return &Target.getSymA()->getSymbol().AliasedSymbol(); 371 return NULL; 372 } 373 374 const MCSymbol *PPCELFObjectWriter::undefinedExplicitRelSym(const MCValue &Target, 375 const MCFixup &Fixup, 376 bool IsPCRel) const { 377 assert(Target.getSymA() && "SymA cannot be 0"); 378 const MCSymbol &Symbol = Target.getSymA()->getSymbol().AliasedSymbol(); 379 380 unsigned RelocType = getRelocTypeInner(Target, Fixup, IsPCRel); 381 382 // The .odp creation emits a relocation against the symbol ".TOC." which 383 // create a R_PPC64_TOC relocation. However the relocation symbol name 384 // in final object creation should be NULL, since the symbol does not 385 // really exist, it is just the reference to TOC base for the current 386 // object file. 387 bool EmitThisSym = RelocType != ELF::R_PPC64_TOC; 388 389 if (EmitThisSym && !Symbol.isTemporary()) 390 return &Symbol; 391 return NULL; 392 } 393 394 MCObjectWriter *llvm::createPPCELFObjectWriter(raw_ostream &OS, 395 bool Is64Bit, 396 uint8_t OSABI) { 397 MCELFObjectTargetWriter *MOTW = new PPCELFObjectWriter(Is64Bit, OSABI); 398 return createELFObjectWriter(MOTW, OS, /*IsLittleEndian=*/false); 399 } 400