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: 232 /* We don't have R_PPC64_GOT_TPREL16, but since GOT offsets 233 are always 4-aligned, we can use R_PPC64_GOT_TPREL16_DS. */ 234 Type = ELF::R_PPC64_GOT_TPREL16_DS; 235 break; 236 case MCSymbolRefExpr::VK_PPC_GOT_TPREL_LO: 237 /* We don't have R_PPC64_GOT_TPREL16_LO, but since GOT offsets 238 are always 4-aligned, we can use R_PPC64_GOT_TPREL16_LO_DS. */ 239 Type = ELF::R_PPC64_GOT_TPREL16_LO_DS; 240 break; 241 case MCSymbolRefExpr::VK_PPC_GOT_TPREL_HI: 242 Type = ELF::R_PPC64_GOT_TPREL16_HI; 243 break; 244 case MCSymbolRefExpr::VK_PPC_GOT_DTPREL: 245 /* We don't have R_PPC64_GOT_DTPREL16, but since GOT offsets 246 are always 4-aligned, we can use R_PPC64_GOT_DTPREL16_DS. */ 247 Type = ELF::R_PPC64_GOT_DTPREL16_DS; 248 break; 249 case MCSymbolRefExpr::VK_PPC_GOT_DTPREL_LO: 250 /* We don't have R_PPC64_GOT_DTPREL16_LO, but since GOT offsets 251 are always 4-aligned, we can use R_PPC64_GOT_DTPREL16_LO_DS. */ 252 Type = ELF::R_PPC64_GOT_DTPREL16_LO_DS; 253 break; 254 case MCSymbolRefExpr::VK_PPC_GOT_TPREL_HA: 255 Type = ELF::R_PPC64_GOT_TPREL16_HA; 256 break; 257 case MCSymbolRefExpr::VK_PPC_GOT_DTPREL_HI: 258 Type = ELF::R_PPC64_GOT_DTPREL16_HI; 259 break; 260 case MCSymbolRefExpr::VK_PPC_GOT_DTPREL_HA: 261 Type = ELF::R_PPC64_GOT_DTPREL16_HA; 262 break; 263 } 264 break; 265 case PPC::fixup_ppc_half16ds: 266 switch (Modifier) { 267 default: llvm_unreachable("Unsupported Modifier"); 268 case MCSymbolRefExpr::VK_None: 269 Type = ELF::R_PPC64_ADDR16_DS; 270 break; 271 case MCSymbolRefExpr::VK_PPC_LO: 272 Type = ELF::R_PPC64_ADDR16_LO_DS; 273 break; 274 case MCSymbolRefExpr::VK_GOT: 275 Type = ELF::R_PPC64_GOT16_DS; 276 break; 277 case MCSymbolRefExpr::VK_PPC_GOT_LO: 278 Type = ELF::R_PPC64_GOT16_LO_DS; 279 break; 280 case MCSymbolRefExpr::VK_PPC_TOC: 281 Type = ELF::R_PPC64_TOC16_DS; 282 break; 283 case MCSymbolRefExpr::VK_PPC_TOC_LO: 284 Type = ELF::R_PPC64_TOC16_LO_DS; 285 break; 286 case MCSymbolRefExpr::VK_PPC_TPREL: 287 Type = ELF::R_PPC64_TPREL16_DS; 288 break; 289 case MCSymbolRefExpr::VK_PPC_TPREL_LO: 290 Type = ELF::R_PPC64_TPREL16_LO_DS; 291 break; 292 case MCSymbolRefExpr::VK_PPC_DTPREL: 293 Type = ELF::R_PPC64_DTPREL16_DS; 294 break; 295 case MCSymbolRefExpr::VK_PPC_DTPREL_LO: 296 Type = ELF::R_PPC64_DTPREL16_LO_DS; 297 break; 298 case MCSymbolRefExpr::VK_PPC_GOT_TPREL: 299 Type = ELF::R_PPC64_GOT_TPREL16_DS; 300 break; 301 case MCSymbolRefExpr::VK_PPC_GOT_TPREL_LO: 302 Type = ELF::R_PPC64_GOT_TPREL16_LO_DS; 303 break; 304 case MCSymbolRefExpr::VK_PPC_GOT_DTPREL: 305 Type = ELF::R_PPC64_GOT_DTPREL16_DS; 306 break; 307 case MCSymbolRefExpr::VK_PPC_GOT_DTPREL_LO: 308 Type = ELF::R_PPC64_GOT_DTPREL16_LO_DS; 309 break; 310 } 311 break; 312 case PPC::fixup_ppc_nofixup: 313 switch (Modifier) { 314 default: llvm_unreachable("Unsupported Modifier"); 315 case MCSymbolRefExpr::VK_PPC_TLSGD: 316 Type = ELF::R_PPC64_TLSGD; 317 break; 318 case MCSymbolRefExpr::VK_PPC_TLSLD: 319 Type = ELF::R_PPC64_TLSLD; 320 break; 321 case MCSymbolRefExpr::VK_PPC_TLS: 322 Type = ELF::R_PPC64_TLS; 323 break; 324 } 325 break; 326 case FK_Data_8: 327 switch (Modifier) { 328 default: llvm_unreachable("Unsupported Modifier"); 329 case MCSymbolRefExpr::VK_PPC_TOCBASE: 330 Type = ELF::R_PPC64_TOC; 331 break; 332 case MCSymbolRefExpr::VK_None: 333 Type = ELF::R_PPC64_ADDR64; 334 break; 335 case MCSymbolRefExpr::VK_PPC_DTPMOD: 336 Type = ELF::R_PPC64_DTPMOD64; 337 break; 338 case MCSymbolRefExpr::VK_PPC_TPREL: 339 Type = ELF::R_PPC64_TPREL64; 340 break; 341 case MCSymbolRefExpr::VK_PPC_DTPREL: 342 Type = ELF::R_PPC64_DTPREL64; 343 break; 344 } 345 break; 346 case FK_Data_4: 347 Type = ELF::R_PPC_ADDR32; 348 break; 349 case FK_Data_2: 350 Type = ELF::R_PPC_ADDR16; 351 break; 352 } 353 } 354 return Type; 355 } 356 357 unsigned PPCELFObjectWriter::GetRelocType(const MCValue &Target, 358 const MCFixup &Fixup, 359 bool IsPCRel, 360 bool IsRelocWithSymbol, 361 int64_t Addend) const { 362 return getRelocTypeInner(Target, Fixup, IsPCRel); 363 } 364 365 const MCSymbol *PPCELFObjectWriter::ExplicitRelSym(const MCAssembler &Asm, 366 const MCValue &Target, 367 const MCFragment &F, 368 const MCFixup &Fixup, 369 bool IsPCRel) const { 370 assert(Target.getSymA() && "SymA cannot be 0"); 371 MCSymbolRefExpr::VariantKind Modifier = Target.isAbsolute() ? 372 MCSymbolRefExpr::VK_None : Target.getSymA()->getKind(); 373 374 bool EmitThisSym; 375 switch (Modifier) { 376 // GOT references always need a relocation, even if the 377 // target symbol is local. 378 case MCSymbolRefExpr::VK_GOT: 379 case MCSymbolRefExpr::VK_PPC_GOT_LO: 380 case MCSymbolRefExpr::VK_PPC_GOT_HI: 381 case MCSymbolRefExpr::VK_PPC_GOT_HA: 382 EmitThisSym = true; 383 break; 384 default: 385 EmitThisSym = false; 386 break; 387 } 388 389 if (EmitThisSym) 390 return &Target.getSymA()->getSymbol().AliasedSymbol(); 391 return NULL; 392 } 393 394 const MCSymbol *PPCELFObjectWriter::undefinedExplicitRelSym(const MCValue &Target, 395 const MCFixup &Fixup, 396 bool IsPCRel) const { 397 assert(Target.getSymA() && "SymA cannot be 0"); 398 const MCSymbol &Symbol = Target.getSymA()->getSymbol().AliasedSymbol(); 399 400 unsigned RelocType = getRelocTypeInner(Target, Fixup, IsPCRel); 401 402 // The .odp creation emits a relocation against the symbol ".TOC." which 403 // create a R_PPC64_TOC relocation. However the relocation symbol name 404 // in final object creation should be NULL, since the symbol does not 405 // really exist, it is just the reference to TOC base for the current 406 // object file. 407 bool EmitThisSym = RelocType != ELF::R_PPC64_TOC; 408 409 if (EmitThisSym && !Symbol.isTemporary()) 410 return &Symbol; 411 return NULL; 412 } 413 414 MCObjectWriter *llvm::createPPCELFObjectWriter(raw_ostream &OS, 415 bool Is64Bit, 416 uint8_t OSABI) { 417 MCELFObjectTargetWriter *MOTW = new PPCELFObjectWriter(Is64Bit, OSABI); 418 return createELFObjectWriter(MOTW, OS, /*IsLittleEndian=*/false); 419 } 420
