Shih-wei Liao | 5460a1f | 2012-03-16 22:41:16 -0700 | [diff] [blame] | 1 | //===- ELFObjectWriter.cpp ------------------------------------------------===// |
| 2 | // |
| 3 | // The MCLinker Project |
| 4 | // |
| 5 | // This file is distributed under the University of Illinois Open Source |
| 6 | // License. See LICENSE.TXT for details. |
| 7 | // |
| 8 | //===----------------------------------------------------------------------===// |
Shih-wei Liao | 22add6f | 2012-12-15 17:21:00 -0800 | [diff] [blame] | 9 | #include <mcld/LD/ELFObjectWriter.h> |
Shih-wei Liao | 5460a1f | 2012-03-16 22:41:16 -0700 | [diff] [blame] | 10 | |
Shih-wei Liao | 22add6f | 2012-12-15 17:21:00 -0800 | [diff] [blame] | 11 | #include <mcld/Module.h> |
Shih-wei Liao | d0fbbb2 | 2013-01-03 06:23:31 -0800 | [diff] [blame] | 12 | #include <mcld/LinkerConfig.h> |
Shih-wei Liao | 22add6f | 2012-12-15 17:21:00 -0800 | [diff] [blame] | 13 | #include <mcld/Target/GNULDBackend.h> |
Shih-wei Liao | 22add6f | 2012-12-15 17:21:00 -0800 | [diff] [blame] | 14 | #include <mcld/Support/MemoryArea.h> |
Stephen Hines | 6f75755 | 2013-03-04 19:51:03 -0800 | [diff] [blame^] | 15 | #include <mcld/Support/MemoryRegion.h> |
| 16 | #include <mcld/Support/MsgHandling.h> |
| 17 | #include <mcld/ADT/SizeTraits.h> |
| 18 | #include <mcld/Fragment/FragmentLinker.h> |
| 19 | #include <mcld/Fragment/AlignFragment.h> |
| 20 | #include <mcld/Fragment/FillFragment.h> |
| 21 | #include <mcld/Fragment/RegionFragment.h> |
| 22 | #include <mcld/Fragment/Stub.h> |
| 23 | #include <mcld/Fragment/NullFragment.h> |
| 24 | #include <mcld/LD/LDSection.h> |
| 25 | #include <mcld/LD/SectionData.h> |
| 26 | #include <mcld/LD/ELFSegment.h> |
| 27 | #include <mcld/LD/ELFSegmentFactory.h> |
| 28 | #include <mcld/LD/RelocData.h> |
| 29 | #include <mcld/LD/EhFrame.h> |
Shih-wei Liao | 22add6f | 2012-12-15 17:21:00 -0800 | [diff] [blame] | 30 | |
Stephen Hines | 6f75755 | 2013-03-04 19:51:03 -0800 | [diff] [blame^] | 31 | #include <llvm/Support/ErrorHandling.h> |
Shih-wei Liao | 22add6f | 2012-12-15 17:21:00 -0800 | [diff] [blame] | 32 | #include <llvm/Support/system_error.h> |
Stephen Hines | 6f75755 | 2013-03-04 19:51:03 -0800 | [diff] [blame^] | 33 | #include <llvm/Support/ELF.h> |
| 34 | #include <llvm/Support/Casting.h> |
Shih-wei Liao | d0fbbb2 | 2013-01-03 06:23:31 -0800 | [diff] [blame] | 35 | |
Shih-wei Liao | 22add6f | 2012-12-15 17:21:00 -0800 | [diff] [blame] | 36 | using namespace llvm; |
Stephen Hines | 6f75755 | 2013-03-04 19:51:03 -0800 | [diff] [blame^] | 37 | using namespace llvm::ELF; |
Shih-wei Liao | 5460a1f | 2012-03-16 22:41:16 -0700 | [diff] [blame] | 38 | using namespace mcld; |
| 39 | |
Shih-wei Liao | 22add6f | 2012-12-15 17:21:00 -0800 | [diff] [blame] | 40 | //===----------------------------------------------------------------------===// |
Shih-wei Liao | 5460a1f | 2012-03-16 22:41:16 -0700 | [diff] [blame] | 41 | // ELFObjectWriter |
Shih-wei Liao | 22add6f | 2012-12-15 17:21:00 -0800 | [diff] [blame] | 42 | //===----------------------------------------------------------------------===// |
| 43 | ELFObjectWriter::ELFObjectWriter(GNULDBackend& pBackend, |
Shih-wei Liao | d0fbbb2 | 2013-01-03 06:23:31 -0800 | [diff] [blame] | 44 | const LinkerConfig& pConfig) |
Stephen Hines | 6f75755 | 2013-03-04 19:51:03 -0800 | [diff] [blame^] | 45 | : ObjectWriter(), m_Backend(pBackend), m_Config(pConfig) |
| 46 | { |
Shih-wei Liao | 5460a1f | 2012-03-16 22:41:16 -0700 | [diff] [blame] | 47 | } |
| 48 | |
| 49 | ELFObjectWriter::~ELFObjectWriter() |
| 50 | { |
| 51 | } |
| 52 | |
Stephen Hines | 6f75755 | 2013-03-04 19:51:03 -0800 | [diff] [blame^] | 53 | void ELFObjectWriter::writeSection(MemoryArea& pOutput, LDSection *section) |
| 54 | { |
| 55 | MemoryRegion* region; |
| 56 | // Request output region |
| 57 | switch (section->kind()) { |
| 58 | case LDFileFormat::Note: |
| 59 | if (section->getSectionData() == NULL) |
| 60 | return; |
| 61 | // Fall through |
| 62 | case LDFileFormat::Regular: |
| 63 | case LDFileFormat::Relocation: |
| 64 | case LDFileFormat::Target: |
| 65 | case LDFileFormat::Debug: |
| 66 | case LDFileFormat::GCCExceptTable: |
| 67 | case LDFileFormat::EhFrame: { |
| 68 | region = pOutput.request(section->offset(), section->size()); |
| 69 | if (NULL == region) { |
| 70 | llvm::report_fatal_error(llvm::Twine("cannot get enough memory region for output section `") + |
| 71 | llvm::Twine(section->name()) + |
| 72 | llvm::Twine("'.\n")); |
| 73 | } |
| 74 | break; |
| 75 | } |
| 76 | case LDFileFormat::Null: |
| 77 | case LDFileFormat::NamePool: |
| 78 | case LDFileFormat::BSS: |
| 79 | case LDFileFormat::MetaData: |
| 80 | case LDFileFormat::Version: |
| 81 | case LDFileFormat::EhFrameHdr: |
| 82 | case LDFileFormat::StackNote: |
| 83 | // Ignore these sections |
| 84 | return; |
| 85 | default: |
| 86 | llvm::errs() << "WARNING: unsupported section kind: " |
| 87 | << section->kind() |
| 88 | << " of section " |
| 89 | << section->name() |
| 90 | << ".\n"; |
| 91 | return; |
| 92 | } |
| 93 | |
| 94 | // Write out sections with data |
| 95 | switch(section->kind()) { |
| 96 | case LDFileFormat::GCCExceptTable: |
| 97 | case LDFileFormat::EhFrame: |
| 98 | case LDFileFormat::Regular: |
| 99 | case LDFileFormat::Debug: |
| 100 | case LDFileFormat::Note: |
| 101 | // FIXME: if optimization of exception handling sections is enabled, |
| 102 | // then we should emit these sections by the other way. |
| 103 | emitSectionData(*section, *region); |
| 104 | break; |
| 105 | case LDFileFormat::Relocation: |
| 106 | emitRelocation(m_Config, *section, *region); |
| 107 | break; |
| 108 | case LDFileFormat::Target: |
| 109 | target().emitSectionData(*section, *region); |
| 110 | break; |
| 111 | default: |
| 112 | llvm_unreachable("invalid section kind"); |
| 113 | } |
| 114 | } |
| 115 | |
Shih-wei Liao | 22add6f | 2012-12-15 17:21:00 -0800 | [diff] [blame] | 116 | llvm::error_code ELFObjectWriter::writeObject(Module& pModule, |
| 117 | MemoryArea& pOutput) |
| 118 | { |
Stephen Hines | 6f75755 | 2013-03-04 19:51:03 -0800 | [diff] [blame^] | 119 | bool is_dynobj = m_Config.codeGenType() == LinkerConfig::DynObj; |
| 120 | bool is_exec = m_Config.codeGenType() == LinkerConfig::Exec; |
| 121 | bool is_binary = m_Config.codeGenType() == LinkerConfig::Binary; |
| 122 | bool is_object = m_Config.codeGenType() == LinkerConfig::Object; |
Shih-wei Liao | 22add6f | 2012-12-15 17:21:00 -0800 | [diff] [blame] | 123 | |
Stephen Hines | 6f75755 | 2013-03-04 19:51:03 -0800 | [diff] [blame^] | 124 | assert(is_dynobj || is_exec || is_binary || is_object); |
| 125 | |
| 126 | if (is_dynobj || is_exec) { |
| 127 | // Write out the interpreter section: .interp |
| 128 | target().emitInterp(pOutput); |
| 129 | |
| 130 | // Write out name pool sections: .dynsym, .dynstr, .hash |
| 131 | target().emitDynNamePools(pModule, pOutput); |
| 132 | } |
| 133 | |
| 134 | if (is_object || is_dynobj || is_exec) { |
| 135 | // Write out name pool sections: .symtab, .strtab |
| 136 | target().emitRegNamePools(pModule, pOutput); |
| 137 | } |
| 138 | |
| 139 | if (is_binary) { |
| 140 | // Iterate over the loadable segments and write the corresponding sections |
| 141 | ELFSegmentFactory::iterator seg, segEnd = target().elfSegmentTable().end(); |
| 142 | |
| 143 | for (seg = target().elfSegmentTable().begin(); seg != segEnd; ++seg) { |
| 144 | if (llvm::ELF::PT_LOAD == (*seg).type()) { |
| 145 | ELFSegment::sect_iterator sect, sectEnd = (*seg).end(); |
| 146 | for (sect = (*seg).begin(); sect != sectEnd; ++sect) |
| 147 | writeSection(pOutput, *sect); |
Shih-wei Liao | 22add6f | 2012-12-15 17:21:00 -0800 | [diff] [blame] | 148 | } |
| 149 | } |
Stephen Hines | 6f75755 | 2013-03-04 19:51:03 -0800 | [diff] [blame^] | 150 | } else { |
| 151 | // Write out regular ELF sections |
| 152 | Module::iterator sect, sectEnd = pModule.end(); |
| 153 | for (sect = pModule.begin(); sect != sectEnd; ++sect) |
| 154 | writeSection(pOutput, *sect); |
Shih-wei Liao | 22add6f | 2012-12-15 17:21:00 -0800 | [diff] [blame] | 155 | |
Stephen Hines | 6f75755 | 2013-03-04 19:51:03 -0800 | [diff] [blame^] | 156 | emitShStrTab(target().getOutputFormat()->getShStrTab(), pModule, pOutput); |
| 157 | |
| 158 | if (m_Config.targets().is32Bits()) { |
| 159 | // Write out ELF header |
| 160 | // Write out section header table |
| 161 | writeELFHeader<32>(m_Config, pModule, pOutput); |
| 162 | if (is_dynobj || is_exec) |
| 163 | emitProgramHeader<32>(pOutput); |
| 164 | |
| 165 | emitSectionHeader<32>(pModule, m_Config, pOutput); |
Shih-wei Liao | 22add6f | 2012-12-15 17:21:00 -0800 | [diff] [blame] | 166 | } |
Stephen Hines | 6f75755 | 2013-03-04 19:51:03 -0800 | [diff] [blame^] | 167 | else if (m_Config.targets().is64Bits()) { |
| 168 | // Write out ELF header |
| 169 | // Write out section header table |
| 170 | writeELFHeader<64>(m_Config, pModule, pOutput); |
| 171 | if (is_dynobj || is_exec) |
| 172 | emitProgramHeader<64>(pOutput); |
Shih-wei Liao | 22add6f | 2012-12-15 17:21:00 -0800 | [diff] [blame] | 173 | |
Stephen Hines | 6f75755 | 2013-03-04 19:51:03 -0800 | [diff] [blame^] | 174 | emitSectionHeader<64>(pModule, m_Config, pOutput); |
| 175 | } |
| 176 | else |
| 177 | return make_error_code(errc::not_supported); |
Shih-wei Liao | 22add6f | 2012-12-15 17:21:00 -0800 | [diff] [blame] | 178 | } |
Shih-wei Liao | 22add6f | 2012-12-15 17:21:00 -0800 | [diff] [blame] | 179 | |
| 180 | pOutput.clear(); |
| 181 | return llvm::make_error_code(llvm::errc::success); |
| 182 | } |
Shih-wei Liao | 5460a1f | 2012-03-16 22:41:16 -0700 | [diff] [blame] | 183 | |
Stephen Hines | 6f75755 | 2013-03-04 19:51:03 -0800 | [diff] [blame^] | 184 | // writeELFHeader - emit ElfXX_Ehdr |
| 185 | template<size_t SIZE> |
| 186 | void ELFObjectWriter::writeELFHeader(const LinkerConfig& pConfig, |
| 187 | const Module& pModule, |
| 188 | MemoryArea& pOutput) const |
| 189 | { |
| 190 | typedef typename ELFSizeTraits<SIZE>::Ehdr ElfXX_Ehdr; |
| 191 | typedef typename ELFSizeTraits<SIZE>::Shdr ElfXX_Shdr; |
| 192 | typedef typename ELFSizeTraits<SIZE>::Phdr ElfXX_Phdr; |
| 193 | |
| 194 | // ELF header must start from 0x0 |
| 195 | MemoryRegion *region = pOutput.request(0, sizeof(ElfXX_Ehdr)); |
| 196 | ElfXX_Ehdr* header = (ElfXX_Ehdr*)region->start(); |
| 197 | |
| 198 | memcpy(header->e_ident, ElfMagic, EI_MAG3+1); |
| 199 | |
| 200 | header->e_ident[EI_CLASS] = (SIZE == 32) ? ELFCLASS32 : ELFCLASS64; |
| 201 | header->e_ident[EI_DATA] = pConfig.targets().isLittleEndian()? |
| 202 | ELFDATA2LSB : ELFDATA2MSB; |
| 203 | header->e_ident[EI_VERSION] = target().getInfo().ELFVersion(); |
| 204 | header->e_ident[EI_OSABI] = target().getInfo().OSABI(); |
| 205 | header->e_ident[EI_ABIVERSION] = target().getInfo().ABIVersion(); |
| 206 | |
| 207 | // FIXME: add processor-specific and core file types. |
| 208 | switch(pConfig.codeGenType()) { |
| 209 | case LinkerConfig::Object: |
| 210 | header->e_type = ET_REL; |
| 211 | break; |
| 212 | case LinkerConfig::DynObj: |
| 213 | header->e_type = ET_DYN; |
| 214 | break; |
| 215 | case LinkerConfig::Exec: |
| 216 | header->e_type = ET_EXEC; |
| 217 | break; |
| 218 | default: |
| 219 | llvm::errs() << "unspported output file type: " << pConfig.codeGenType() << ".\n"; |
| 220 | header->e_type = ET_NONE; |
| 221 | } |
| 222 | header->e_machine = target().getInfo().machine(); |
| 223 | header->e_version = header->e_ident[EI_VERSION]; |
| 224 | header->e_entry = getEntryPoint(pConfig, pModule); |
| 225 | |
| 226 | if (LinkerConfig::Object != pConfig.codeGenType()) |
| 227 | header->e_phoff = sizeof(ElfXX_Ehdr); |
| 228 | else |
| 229 | header->e_phoff = 0x0; |
| 230 | |
| 231 | header->e_shoff = getLastStartOffset<SIZE>(pModule); |
| 232 | header->e_flags = target().getInfo().flags(); |
| 233 | header->e_ehsize = sizeof(ElfXX_Ehdr); |
| 234 | header->e_phentsize = sizeof(ElfXX_Phdr); |
| 235 | header->e_phnum = target().numOfSegments(); |
| 236 | header->e_shentsize = sizeof(ElfXX_Shdr); |
| 237 | header->e_shnum = pModule.size(); |
| 238 | header->e_shstrndx = pModule.getSection(".shstrtab")->index(); |
| 239 | } |
| 240 | |
| 241 | /// getEntryPoint |
| 242 | uint64_t ELFObjectWriter::getEntryPoint(const LinkerConfig& pConfig, |
| 243 | const Module& pModule) const |
| 244 | { |
| 245 | llvm::StringRef entry_name; |
| 246 | if (pConfig.options().hasEntry()) |
| 247 | entry_name = pConfig.options().entry(); |
| 248 | else |
| 249 | entry_name = target().getInfo().entry(); |
| 250 | |
| 251 | uint64_t result = 0x0; |
| 252 | |
| 253 | bool issue_warning = (pConfig.options().hasEntry() && |
| 254 | LinkerConfig::Object != pConfig.codeGenType() && |
| 255 | LinkerConfig::DynObj != pConfig.codeGenType()); |
| 256 | |
| 257 | const LDSymbol* entry_symbol = pModule.getNamePool().findSymbol(entry_name); |
| 258 | |
| 259 | // found the symbol |
| 260 | if (NULL != entry_symbol) { |
| 261 | if (entry_symbol->desc() != ResolveInfo::Define && issue_warning) { |
| 262 | llvm::errs() << "WARNING: entry symbol '" |
| 263 | << entry_symbol->name() |
| 264 | << "' exists but is not defined.\n"; |
| 265 | } |
| 266 | result = entry_symbol->value(); |
| 267 | } |
| 268 | // not in the symbol pool |
| 269 | else { |
| 270 | // We should parse entry as a number. |
| 271 | // @ref GNU ld manual, Options -e. e.g., -e 0x1000. |
| 272 | char* endptr; |
| 273 | result = strtoull(entry_name.data(), &endptr, 0); |
| 274 | if (*endptr != '\0') { |
| 275 | if (issue_warning) { |
| 276 | llvm::errs() << "cannot find entry symbol '" |
| 277 | << entry_name.data() |
| 278 | << "'.\n"; |
| 279 | } |
| 280 | result = 0x0; |
| 281 | } |
| 282 | } |
| 283 | return result; |
| 284 | } |
| 285 | |
| 286 | // emitSectionHeader - emit ElfXX_Shdr |
| 287 | template<size_t SIZE> |
| 288 | void ELFObjectWriter::emitSectionHeader(const Module& pModule, |
| 289 | const LinkerConfig& pConfig, |
| 290 | MemoryArea& pOutput) const |
| 291 | { |
| 292 | typedef typename ELFSizeTraits<SIZE>::Shdr ElfXX_Shdr; |
| 293 | |
| 294 | // emit section header |
| 295 | unsigned int sectNum = pModule.size(); |
| 296 | unsigned int header_size = sizeof(ElfXX_Shdr) * sectNum; |
| 297 | MemoryRegion* region = pOutput.request(getLastStartOffset<SIZE>(pModule), |
| 298 | header_size); |
| 299 | ElfXX_Shdr* shdr = (ElfXX_Shdr*)region->start(); |
| 300 | |
| 301 | // Iterate the SectionTable in LDContext |
| 302 | unsigned int sectIdx = 0; |
| 303 | unsigned int shstridx = 0; // NULL section has empty name |
| 304 | for (; sectIdx < sectNum; ++sectIdx) { |
| 305 | const LDSection *ld_sect = pModule.getSectionTable().at(sectIdx); |
| 306 | shdr[sectIdx].sh_name = shstridx; |
| 307 | shdr[sectIdx].sh_type = ld_sect->type(); |
| 308 | shdr[sectIdx].sh_flags = ld_sect->flag(); |
| 309 | shdr[sectIdx].sh_addr = ld_sect->addr(); |
| 310 | shdr[sectIdx].sh_offset = ld_sect->offset(); |
| 311 | shdr[sectIdx].sh_size = ld_sect->size(); |
| 312 | shdr[sectIdx].sh_addralign = ld_sect->align(); |
| 313 | shdr[sectIdx].sh_entsize = getSectEntrySize<SIZE>(*ld_sect); |
| 314 | shdr[sectIdx].sh_link = getSectLink(*ld_sect, pConfig); |
| 315 | shdr[sectIdx].sh_info = getSectInfo(*ld_sect); |
| 316 | |
| 317 | // adjust strshidx |
| 318 | shstridx += ld_sect->name().size() + 1; |
| 319 | } |
| 320 | } |
| 321 | |
| 322 | // emitProgramHeader - emit ElfXX_Phdr |
| 323 | template<size_t SIZE> |
| 324 | void ELFObjectWriter::emitProgramHeader(MemoryArea& pOutput) const |
| 325 | { |
| 326 | typedef typename ELFSizeTraits<SIZE>::Ehdr ElfXX_Ehdr; |
| 327 | typedef typename ELFSizeTraits<SIZE>::Phdr ElfXX_Phdr; |
| 328 | |
| 329 | uint64_t start_offset, phdr_size; |
| 330 | |
| 331 | start_offset = sizeof(ElfXX_Ehdr); |
| 332 | phdr_size = sizeof(ElfXX_Phdr); |
| 333 | // Program header must start directly after ELF header |
| 334 | MemoryRegion *region = pOutput.request(start_offset, |
| 335 | target().numOfSegments() * phdr_size); |
| 336 | |
| 337 | ElfXX_Phdr* phdr = (ElfXX_Phdr*)region->start(); |
| 338 | |
| 339 | // Iterate the elf segment table in GNULDBackend |
| 340 | size_t index = 0; |
| 341 | ELFSegmentFactory::const_iterator seg = target().elfSegmentTable().begin(), |
| 342 | segEnd = target().elfSegmentTable().end(); |
| 343 | for (; seg != segEnd; ++seg, ++index) { |
| 344 | phdr[index].p_type = (*seg).type(); |
| 345 | phdr[index].p_flags = (*seg).flag(); |
| 346 | phdr[index].p_offset = (*seg).offset(); |
| 347 | phdr[index].p_vaddr = (*seg).vaddr(); |
| 348 | phdr[index].p_paddr = (*seg).paddr(); |
| 349 | phdr[index].p_filesz = (*seg).filesz(); |
| 350 | phdr[index].p_memsz = (*seg).memsz(); |
| 351 | phdr[index].p_align = (*seg).align(); |
| 352 | } |
| 353 | } |
| 354 | |
| 355 | /// emitShStrTab - emit section string table |
| 356 | void |
| 357 | ELFObjectWriter::emitShStrTab(const LDSection& pShStrTab, |
| 358 | const Module& pModule, |
| 359 | MemoryArea& pOutput) |
| 360 | { |
| 361 | // write out data |
| 362 | MemoryRegion* region = pOutput.request(pShStrTab.offset(), pShStrTab.size()); |
| 363 | unsigned char* data = region->start(); |
| 364 | size_t shstrsize = 0; |
| 365 | Module::const_iterator section, sectEnd = pModule.end(); |
| 366 | for (section = pModule.begin(); section != sectEnd; ++section) { |
| 367 | strcpy((char*)(data + shstrsize), (*section)->name().data()); |
| 368 | shstrsize += (*section)->name().size() + 1; |
| 369 | } |
| 370 | } |
| 371 | |
| 372 | /// emitSectionData |
| 373 | void |
| 374 | ELFObjectWriter::emitSectionData(const LDSection& pSection, |
| 375 | MemoryRegion& pRegion) const |
| 376 | { |
| 377 | const SectionData* sd = NULL; |
| 378 | switch (pSection.kind()) { |
| 379 | case LDFileFormat::Relocation: |
| 380 | assert(pSection.hasRelocData()); |
| 381 | return; |
| 382 | case LDFileFormat::EhFrame: |
| 383 | assert(pSection.hasEhFrame()); |
| 384 | sd = &pSection.getEhFrame()->getSectionData(); |
| 385 | break; |
| 386 | default: |
| 387 | assert(pSection.hasSectionData()); |
| 388 | sd = pSection.getSectionData(); |
| 389 | break; |
| 390 | } |
| 391 | emitSectionData(*sd, pRegion); |
| 392 | } |
| 393 | |
| 394 | /// emitRelocation |
| 395 | void ELFObjectWriter::emitRelocation(const LinkerConfig& pConfig, |
| 396 | const LDSection& pSection, |
| 397 | MemoryRegion& pRegion) const |
| 398 | { |
| 399 | const RelocData* sect_data = pSection.getRelocData(); |
| 400 | assert(NULL != sect_data && "SectionData is NULL in emitRelocation!"); |
| 401 | |
| 402 | if (pSection.type() == SHT_REL) { |
| 403 | if (pConfig.targets().is32Bits()) |
| 404 | emitRel<32>(pConfig, *sect_data, pRegion); |
| 405 | else if (pConfig.targets().is64Bits()) |
| 406 | emitRel<64>(pConfig, *sect_data, pRegion); |
| 407 | else { |
| 408 | fatal(diag::unsupported_bitclass) << pConfig.targets().triple().str() |
| 409 | << pConfig.targets().bitclass(); |
| 410 | } |
| 411 | } else if (pSection.type() == SHT_RELA) { |
| 412 | if (pConfig.targets().is32Bits()) |
| 413 | emitRela<32>(pConfig, *sect_data, pRegion); |
| 414 | else if (pConfig.targets().is64Bits()) |
| 415 | emitRela<64>(pConfig, *sect_data, pRegion); |
| 416 | else { |
| 417 | fatal(diag::unsupported_bitclass) << pConfig.targets().triple().str() |
| 418 | << pConfig.targets().bitclass(); |
| 419 | } |
| 420 | } else |
| 421 | llvm::report_fatal_error("unsupported relocation section type!"); |
| 422 | } |
| 423 | |
| 424 | |
| 425 | // emitRel - emit ElfXX_Rel |
| 426 | template<size_t SIZE> |
| 427 | void ELFObjectWriter::emitRel(const LinkerConfig& pConfig, |
| 428 | const RelocData& pRelocData, |
| 429 | MemoryRegion& pRegion) const |
| 430 | { |
| 431 | typedef typename ELFSizeTraits<SIZE>::Rel ElfXX_Rel; |
| 432 | typedef typename ELFSizeTraits<SIZE>::Addr ElfXX_Addr; |
| 433 | typedef typename ELFSizeTraits<SIZE>::Word ElfXX_Word; |
| 434 | |
| 435 | ElfXX_Rel* rel = reinterpret_cast<ElfXX_Rel*>(pRegion.start()); |
| 436 | |
| 437 | const Relocation* relocation = 0; |
| 438 | const FragmentRef* frag_ref = 0; |
| 439 | |
| 440 | for (RelocData::const_iterator it = pRelocData.begin(), |
| 441 | ie = pRelocData.end(); it != ie; ++it, ++rel) { |
| 442 | |
| 443 | relocation = &(llvm::cast<Relocation>(*it)); |
| 444 | frag_ref = &(relocation->targetRef()); |
| 445 | |
| 446 | if(LinkerConfig::DynObj == pConfig.codeGenType() || |
| 447 | LinkerConfig::Exec == pConfig.codeGenType()) { |
| 448 | rel->r_offset = static_cast<ElfXX_Addr>( |
| 449 | frag_ref->frag()->getParent()->getSection().addr() + |
| 450 | frag_ref->getOutputOffset()); |
| 451 | } |
| 452 | else { |
| 453 | rel->r_offset = static_cast<ElfXX_Addr>(frag_ref->getOutputOffset()); |
| 454 | } |
| 455 | ElfXX_Word Index; |
| 456 | if( relocation->symInfo() == NULL ) |
| 457 | Index = 0; |
| 458 | else |
| 459 | Index = static_cast<ElfXX_Word>( |
| 460 | target().getSymbolIdx(relocation->symInfo()->outSymbol())); |
| 461 | |
| 462 | rel->setSymbolAndType(Index, relocation->type()); |
| 463 | } |
| 464 | } |
| 465 | |
| 466 | // emitRela - emit ElfXX_Rela |
| 467 | template<size_t SIZE> |
| 468 | void ELFObjectWriter::emitRela(const LinkerConfig& pConfig, |
| 469 | const RelocData& pRelocData, |
| 470 | MemoryRegion& pRegion) const |
| 471 | { |
| 472 | typedef typename ELFSizeTraits<SIZE>::Rela ElfXX_Rela; |
| 473 | typedef typename ELFSizeTraits<SIZE>::Addr ElfXX_Addr; |
| 474 | typedef typename ELFSizeTraits<SIZE>::Word ElfXX_Word; |
| 475 | |
| 476 | ElfXX_Rela* rel = reinterpret_cast<ElfXX_Rela*>(pRegion.start()); |
| 477 | |
| 478 | const Relocation* relocation = 0; |
| 479 | const FragmentRef* frag_ref = 0; |
| 480 | |
| 481 | for (RelocData::const_iterator it = pRelocData.begin(), |
| 482 | ie = pRelocData.end(); it != ie; ++it, ++rel) { |
| 483 | |
| 484 | relocation = &(llvm::cast<Relocation>(*it)); |
| 485 | frag_ref = &(relocation->targetRef()); |
| 486 | |
| 487 | if(LinkerConfig::DynObj == pConfig.codeGenType() || |
| 488 | LinkerConfig::Exec == pConfig.codeGenType()) { |
| 489 | rel->r_offset = static_cast<ElfXX_Addr>( |
| 490 | frag_ref->frag()->getParent()->getSection().addr() + |
| 491 | frag_ref->getOutputOffset()); |
| 492 | } |
| 493 | else { |
| 494 | rel->r_offset = static_cast<ElfXX_Addr>(frag_ref->getOutputOffset()); |
| 495 | } |
| 496 | |
| 497 | ElfXX_Word Index; |
| 498 | if( relocation->symInfo() == NULL ) |
| 499 | Index = 0; |
| 500 | else |
| 501 | Index = static_cast<ElfXX_Word>( |
| 502 | target().getSymbolIdx(relocation->symInfo()->outSymbol())); |
| 503 | |
| 504 | rel->setSymbolAndType(Index, relocation->type()); |
| 505 | rel->r_addend = relocation->addend(); |
| 506 | } |
| 507 | } |
| 508 | |
| 509 | |
| 510 | /// getSectEntrySize - compute ElfXX_Shdr::sh_entsize |
| 511 | template<size_t SIZE> |
| 512 | uint64_t ELFObjectWriter::getSectEntrySize(const LDSection& pSection) const |
| 513 | { |
| 514 | typedef typename ELFSizeTraits<SIZE>::Word ElfXX_Word; |
| 515 | typedef typename ELFSizeTraits<SIZE>::Sym ElfXX_Sym; |
| 516 | typedef typename ELFSizeTraits<SIZE>::Rel ElfXX_Rel; |
| 517 | typedef typename ELFSizeTraits<SIZE>::Rela ElfXX_Rela; |
| 518 | typedef typename ELFSizeTraits<SIZE>::Dyn ElfXX_Dyn; |
| 519 | |
| 520 | if (llvm::ELF::SHT_DYNSYM == pSection.type() || |
| 521 | llvm::ELF::SHT_SYMTAB == pSection.type()) |
| 522 | return sizeof(ElfXX_Sym); |
| 523 | if (llvm::ELF::SHT_REL == pSection.type()) |
| 524 | return sizeof(ElfXX_Rel); |
| 525 | if (llvm::ELF::SHT_RELA == pSection.type()) |
| 526 | return sizeof(ElfXX_Rela); |
| 527 | if (llvm::ELF::SHT_HASH == pSection.type() || |
| 528 | llvm::ELF::SHT_GNU_HASH == pSection.type()) |
| 529 | return sizeof(ElfXX_Word); |
| 530 | if (llvm::ELF::SHT_DYNAMIC == pSection.type()) |
| 531 | return sizeof(ElfXX_Dyn); |
| 532 | return 0x0; |
| 533 | } |
| 534 | |
| 535 | /// getSectLink - compute ElfXX_Shdr::sh_link |
| 536 | uint64_t ELFObjectWriter::getSectLink(const LDSection& pSection, |
| 537 | const LinkerConfig& pConfig) const |
| 538 | { |
| 539 | if (llvm::ELF::SHT_SYMTAB == pSection.type()) |
| 540 | return target().getOutputFormat()->getStrTab().index(); |
| 541 | if (llvm::ELF::SHT_DYNSYM == pSection.type()) |
| 542 | return target().getOutputFormat()->getDynStrTab().index(); |
| 543 | if (llvm::ELF::SHT_DYNAMIC == pSection.type()) |
| 544 | return target().getOutputFormat()->getDynStrTab().index(); |
| 545 | if (llvm::ELF::SHT_HASH == pSection.type() || |
| 546 | llvm::ELF::SHT_GNU_HASH == pSection.type()) |
| 547 | return target().getOutputFormat()->getDynSymTab().index(); |
| 548 | if (llvm::ELF::SHT_REL == pSection.type() || |
| 549 | llvm::ELF::SHT_RELA == pSection.type()) { |
| 550 | if (LinkerConfig::Object == pConfig.codeGenType()) |
| 551 | return target().getOutputFormat()->getSymTab().index(); |
| 552 | else |
| 553 | return target().getOutputFormat()->getDynSymTab().index(); |
| 554 | } |
| 555 | // FIXME: currently we link ARM_EXIDX section to output text section here |
| 556 | if (llvm::ELF::SHT_ARM_EXIDX == pSection.type()) |
| 557 | return target().getOutputFormat()->getText().index(); |
| 558 | return llvm::ELF::SHN_UNDEF; |
| 559 | } |
| 560 | |
| 561 | /// getSectInfo - compute ElfXX_Shdr::sh_info |
| 562 | uint64_t ELFObjectWriter::getSectInfo(const LDSection& pSection) const |
| 563 | { |
| 564 | if (llvm::ELF::SHT_SYMTAB == pSection.type() || |
| 565 | llvm::ELF::SHT_DYNSYM == pSection.type()) |
| 566 | return pSection.getInfo(); |
| 567 | |
| 568 | if (llvm::ELF::SHT_REL == pSection.type() || |
| 569 | llvm::ELF::SHT_RELA == pSection.type()) { |
| 570 | const LDSection* info_link = pSection.getLink(); |
| 571 | if (NULL != info_link) |
| 572 | return info_link->index(); |
| 573 | } |
| 574 | |
| 575 | return 0x0; |
| 576 | } |
| 577 | |
| 578 | /// getLastStartOffset |
| 579 | template<> |
| 580 | uint64_t ELFObjectWriter::getLastStartOffset<32>(const Module& pModule) const |
| 581 | { |
| 582 | const LDSection* lastSect = pModule.back(); |
| 583 | assert(lastSect != NULL); |
| 584 | return Align<32>(lastSect->offset() + lastSect->size()); |
| 585 | } |
| 586 | |
| 587 | /// getLastStartOffset |
| 588 | template<> |
| 589 | uint64_t ELFObjectWriter::getLastStartOffset<64>(const Module& pModule) const |
| 590 | { |
| 591 | const LDSection* lastSect = pModule.back(); |
| 592 | assert(lastSect != NULL); |
| 593 | return Align<64>(lastSect->offset() + lastSect->size()); |
| 594 | } |
| 595 | |
| 596 | /// emitSectionData |
| 597 | void ELFObjectWriter::emitSectionData(const SectionData& pSD, |
| 598 | MemoryRegion& pRegion) const |
| 599 | { |
| 600 | SectionData::const_iterator fragIter, fragEnd = pSD.end(); |
| 601 | size_t cur_offset = 0; |
| 602 | for (fragIter = pSD.begin(); fragIter != fragEnd; ++fragIter) { |
| 603 | size_t size = fragIter->size(); |
| 604 | switch(fragIter->getKind()) { |
| 605 | case Fragment::Region: { |
| 606 | const RegionFragment& region_frag = llvm::cast<RegionFragment>(*fragIter); |
| 607 | const uint8_t* from = region_frag.getRegion().start(); |
| 608 | memcpy(pRegion.getBuffer(cur_offset), from, size); |
| 609 | break; |
| 610 | } |
| 611 | case Fragment::Alignment: { |
| 612 | // TODO: emit values with different sizes (> 1 byte), and emit nops |
| 613 | const AlignFragment& align_frag = llvm::cast<AlignFragment>(*fragIter); |
| 614 | uint64_t count = size / align_frag.getValueSize(); |
| 615 | switch (align_frag.getValueSize()) { |
| 616 | case 1u: |
| 617 | std::memset(pRegion.getBuffer(cur_offset), |
| 618 | align_frag.getValue(), |
| 619 | count); |
| 620 | break; |
| 621 | default: |
| 622 | llvm::report_fatal_error("unsupported value size for align fragment emission yet.\n"); |
| 623 | break; |
| 624 | } |
| 625 | break; |
| 626 | } |
| 627 | case Fragment::Fillment: { |
| 628 | const FillFragment& fill_frag = llvm::cast<FillFragment>(*fragIter); |
| 629 | if (0 == size || |
| 630 | 0 == fill_frag.getValueSize() || |
| 631 | 0 == fill_frag.size()) { |
| 632 | // ignore virtual fillment |
| 633 | break; |
| 634 | } |
| 635 | |
| 636 | uint64_t num_tiles = fill_frag.size() / fill_frag.getValueSize(); |
| 637 | for (uint64_t i = 0; i != num_tiles; ++i) { |
| 638 | std::memset(pRegion.getBuffer(cur_offset), |
| 639 | fill_frag.getValue(), |
| 640 | fill_frag.getValueSize()); |
| 641 | } |
| 642 | break; |
| 643 | } |
| 644 | case Fragment::Stub: { |
| 645 | const Stub& stub_frag = llvm::cast<Stub>(*fragIter); |
| 646 | memcpy(pRegion.getBuffer(cur_offset), stub_frag.getContent(), size); |
| 647 | break; |
| 648 | } |
| 649 | case Fragment::Null: { |
| 650 | assert(0x0 == size); |
| 651 | break; |
| 652 | } |
| 653 | case Fragment::Target: |
| 654 | llvm::report_fatal_error("Target fragment should not be in a regular section.\n"); |
| 655 | break; |
| 656 | default: |
| 657 | llvm::report_fatal_error("invalid fragment should not be in a regular section.\n"); |
| 658 | break; |
| 659 | } |
| 660 | cur_offset += size; |
| 661 | } |
| 662 | } |
| 663 | |