elf_writer_quick.cc revision 53bee42d0f8b454ff4fe5b7e42bdb070c786e3eb
1/* 2 * Copyright (C) 2012 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17#include "elf_writer_quick.h" 18 19#include "base/logging.h" 20#include "base/unix_file/fd_file.h" 21#include "buffered_output_stream.h" 22#include "driver/compiler_driver.h" 23#include "elf_utils.h" 24#include "file_output_stream.h" 25#include "globals.h" 26#include "oat.h" 27#include "oat_writer.h" 28#include "utils.h" 29 30namespace art { 31 32bool ElfWriterQuick::Create(File* elf_file, 33 OatWriter* oat_writer, 34 const std::vector<const DexFile*>& dex_files, 35 const std::string& android_root, 36 bool is_host, 37 const CompilerDriver& driver) { 38 ElfWriterQuick elf_writer(driver, elf_file); 39 return elf_writer.Write(oat_writer, dex_files, android_root, is_host); 40} 41 42bool ElfWriterQuick::Write(OatWriter* oat_writer, 43 const std::vector<const DexFile*>& dex_files_unused, 44 const std::string& android_root_unused, 45 bool is_host_unused) { 46 const bool debug = false; 47 // +-------------------------+ 48 // | Elf32_Ehdr | 49 // +-------------------------+ 50 // | Elf32_Phdr PHDR | 51 // | Elf32_Phdr LOAD R | .dynsym .dynstr .hash .rodata 52 // | Elf32_Phdr LOAD R X | .text 53 // | Elf32_Phdr LOAD RW | .dynamic 54 // | Elf32_Phdr DYNAMIC | .dynamic 55 // +-------------------------+ 56 // | .dynsym | 57 // | Elf32_Sym STN_UNDEF | 58 // | Elf32_Sym oatdata | 59 // | Elf32_Sym oatexec | 60 // | Elf32_Sym oatlastword | 61 // +-------------------------+ 62 // | .dynstr | 63 // | \0 | 64 // | oatdata\0 | 65 // | oatexec\0 | 66 // | oatlastword\0 | 67 // | boot.oat\0 | 68 // +-------------------------+ 69 // | .hash | 70 // | Elf32_Word nbucket = 1 | 71 // | Elf32_Word nchain = 3 | 72 // | Elf32_Word bucket[0] = 0| 73 // | Elf32_Word chain[0] = 1| 74 // | Elf32_Word chain[1] = 2| 75 // | Elf32_Word chain[2] = 3| 76 // +-------------------------+ 77 // | .rodata | 78 // | oatdata..oatexec-4 | 79 // +-------------------------+ 80 // | .text | 81 // | oatexec..oatlastword | 82 // +-------------------------+ 83 // | .dynamic | 84 // | Elf32_Dyn DT_SONAME | 85 // | Elf32_Dyn DT_HASH | 86 // | Elf32_Dyn DT_SYMTAB | 87 // | Elf32_Dyn DT_SYMENT | 88 // | Elf32_Dyn DT_STRTAB | 89 // | Elf32_Dyn DT_STRSZ | 90 // | Elf32_Dyn DT_NULL | 91 // +-------------------------+ 92 // | .shstrtab | 93 // | \0 | 94 // | .dynamic\0 | 95 // | .dynsym\0 | 96 // | .dynstr\0 | 97 // | .hash\0 | 98 // | .rodata\0 | 99 // | .text\0 | 100 // | .shstrtab\0 | 101 // | .debug_frame\0 | 102 // +-------------------------+ 103 // | Elf32_Shdr NULL | 104 // | Elf32_Shdr .dynsym | 105 // | Elf32_Shdr .dynstr | 106 // | Elf32_Shdr .hash | 107 // | Elf32_Shdr .text | 108 // | Elf32_Shdr .rodata | 109 // | Elf32_Shdr .dynamic | 110 // | Elf32_Shdr .shstrtab | 111 // | Elf32_Shdr .debug_info | (Optional) 112 // | Elf32_Shdr .debug_abbrev| (Optional) 113 // | Elf32_Shdr .debug_frame | (Optional) 114 // +-------------------------+ 115 116 // phase 1: computing offsets 117 uint32_t expected_offset = 0; 118 119 // Elf32_Ehdr 120 expected_offset += sizeof(Elf32_Ehdr); 121 122 // PHDR 123 uint32_t phdr_alignment = sizeof(Elf32_Word); 124 uint32_t phdr_offset = expected_offset; 125 const uint8_t PH_PHDR = 0; 126 const uint8_t PH_LOAD_R__ = 1; 127 const uint8_t PH_LOAD_R_X = 2; 128 const uint8_t PH_LOAD_RW_ = 3; 129 const uint8_t PH_DYNAMIC = 4; 130 const uint8_t PH_NUM = 5; 131 uint32_t phdr_size = sizeof(Elf32_Phdr) * PH_NUM; 132 expected_offset += phdr_size; 133 if (debug) { 134 LOG(INFO) << "phdr_offset=" << phdr_offset << std::hex << " " << phdr_offset; 135 LOG(INFO) << "phdr_size=" << phdr_size << std::hex << " " << phdr_size; 136 } 137 138 // .dynsym 139 uint32_t dynsym_alignment = sizeof(Elf32_Word); 140 uint32_t dynsym_offset = expected_offset = RoundUp(expected_offset, dynsym_alignment); 141 const uint8_t SYM_UNDEF = 0; // aka STN_UNDEF 142 const uint8_t SYM_OATDATA = 1; 143 const uint8_t SYM_OATEXEC = 2; 144 const uint8_t SYM_OATLASTWORD = 3; 145 const uint8_t SYM_NUM = 4; 146 uint32_t dynsym_size = sizeof(Elf32_Sym) * SYM_NUM; 147 expected_offset += dynsym_size; 148 if (debug) { 149 LOG(INFO) << "dynsym_offset=" << dynsym_offset << std::hex << " " << dynsym_offset; 150 LOG(INFO) << "dynsym_size=" << dynsym_size << std::hex << " " << dynsym_size; 151 } 152 153 // .dynstr 154 uint32_t dynstr_alignment = 1; 155 uint32_t dynstr_offset = expected_offset = RoundUp(expected_offset, dynstr_alignment); 156 std::string dynstr; 157 dynstr += '\0'; 158 uint32_t dynstr_oatdata_offset = dynstr.size(); 159 dynstr += "oatdata"; 160 dynstr += '\0'; 161 uint32_t dynstr_oatexec_offset = dynstr.size(); 162 dynstr += "oatexec"; 163 dynstr += '\0'; 164 uint32_t dynstr_oatlastword_offset = dynstr.size(); 165 dynstr += "oatlastword"; 166 dynstr += '\0'; 167 uint32_t dynstr_soname_offset = dynstr.size(); 168 std::string file_name(elf_file_->GetPath()); 169 size_t directory_separator_pos = file_name.rfind('/'); 170 if (directory_separator_pos != std::string::npos) { 171 file_name = file_name.substr(directory_separator_pos + 1); 172 } 173 dynstr += file_name; 174 dynstr += '\0'; 175 uint32_t dynstr_size = dynstr.size(); 176 expected_offset += dynstr_size; 177 if (debug) { 178 LOG(INFO) << "dynstr_offset=" << dynstr_offset << std::hex << " " << dynstr_offset; 179 LOG(INFO) << "dynstr_size=" << dynstr_size << std::hex << " " << dynstr_size; 180 } 181 182 // .hash 183 uint32_t hash_alignment = sizeof(Elf32_Word); // Even for 64-bit 184 uint32_t hash_offset = expected_offset = RoundUp(expected_offset, hash_alignment); 185 const uint8_t HASH_NBUCKET = 0; 186 const uint8_t HASH_NCHAIN = 1; 187 const uint8_t HASH_BUCKET0 = 2; 188 const uint8_t HASH_NUM = HASH_BUCKET0 + 1 + SYM_NUM; 189 uint32_t hash_size = sizeof(Elf32_Word) * HASH_NUM; 190 expected_offset += hash_size; 191 if (debug) { 192 LOG(INFO) << "hash_offset=" << hash_offset << std::hex << " " << hash_offset; 193 LOG(INFO) << "hash_size=" << hash_size << std::hex << " " << hash_size; 194 } 195 196 // .rodata 197 uint32_t oat_data_alignment = kPageSize; 198 uint32_t oat_data_offset = expected_offset = RoundUp(expected_offset, oat_data_alignment); 199 const OatHeader& oat_header = oat_writer->GetOatHeader(); 200 CHECK(oat_header.IsValid()); 201 uint32_t oat_data_size = oat_header.GetExecutableOffset(); 202 expected_offset += oat_data_size; 203 if (debug) { 204 LOG(INFO) << "oat_data_offset=" << oat_data_offset << std::hex << " " << oat_data_offset; 205 LOG(INFO) << "oat_data_size=" << oat_data_size << std::hex << " " << oat_data_size; 206 } 207 208 // .text 209 uint32_t oat_exec_alignment = kPageSize; 210 CHECK_ALIGNED(expected_offset, kPageSize); 211 uint32_t oat_exec_offset = expected_offset = RoundUp(expected_offset, oat_exec_alignment); 212 uint32_t oat_exec_size = oat_writer->GetSize() - oat_data_size; 213 expected_offset += oat_exec_size; 214 CHECK_EQ(oat_data_offset + oat_writer->GetSize(), expected_offset); 215 if (debug) { 216 LOG(INFO) << "oat_exec_offset=" << oat_exec_offset << std::hex << " " << oat_exec_offset; 217 LOG(INFO) << "oat_exec_size=" << oat_exec_size << std::hex << " " << oat_exec_size; 218 } 219 220 // .dynamic 221 // alignment would naturally be sizeof(Elf32_Word), but we want this in a new segment 222 uint32_t dynamic_alignment = kPageSize; 223 uint32_t dynamic_offset = expected_offset = RoundUp(expected_offset, dynamic_alignment); 224 const uint8_t DH_SONAME = 0; 225 const uint8_t DH_HASH = 1; 226 const uint8_t DH_SYMTAB = 2; 227 const uint8_t DH_SYMENT = 3; 228 const uint8_t DH_STRTAB = 4; 229 const uint8_t DH_STRSZ = 5; 230 const uint8_t DH_NULL = 6; 231 const uint8_t DH_NUM = 7; 232 uint32_t dynamic_size = sizeof(Elf32_Dyn) * DH_NUM; 233 expected_offset += dynamic_size; 234 if (debug) { 235 LOG(INFO) << "dynamic_offset=" << dynamic_offset << std::hex << " " << dynamic_offset; 236 LOG(INFO) << "dynamic_size=" << dynamic_size << std::hex << " " << dynamic_size; 237 } 238 239 // .shstrtab 240 uint32_t shstrtab_alignment = 1; 241 uint32_t shstrtab_offset = expected_offset = RoundUp(expected_offset, shstrtab_alignment); 242 std::string shstrtab; 243 shstrtab += '\0'; 244 uint32_t shstrtab_dynamic_offset = shstrtab.size(); 245 CHECK_EQ(1U, shstrtab_dynamic_offset); 246 shstrtab += ".dynamic"; 247 shstrtab += '\0'; 248 uint32_t shstrtab_dynsym_offset = shstrtab.size(); 249 shstrtab += ".dynsym"; 250 shstrtab += '\0'; 251 uint32_t shstrtab_dynstr_offset = shstrtab.size(); 252 shstrtab += ".dynstr"; 253 shstrtab += '\0'; 254 uint32_t shstrtab_hash_offset = shstrtab.size(); 255 shstrtab += ".hash"; 256 shstrtab += '\0'; 257 uint32_t shstrtab_rodata_offset = shstrtab.size(); 258 shstrtab += ".rodata"; 259 shstrtab += '\0'; 260 uint32_t shstrtab_text_offset = shstrtab.size(); 261 shstrtab += ".text"; 262 shstrtab += '\0'; 263 uint32_t shstrtab_shstrtab_offset = shstrtab.size(); 264 shstrtab += ".shstrtab"; 265 shstrtab += '\0'; 266 uint32_t shstrtab_debug_info_offset = shstrtab.size(); 267 shstrtab += ".debug_info"; 268 shstrtab += '\0'; 269 uint32_t shstrtab_debug_abbrev_offset = shstrtab.size(); 270 shstrtab += ".debug_abbrev"; 271 shstrtab += '\0'; 272 uint32_t shstrtab_debug_str_offset = shstrtab.size(); 273 shstrtab += ".debug_str"; 274 shstrtab += '\0'; 275 uint32_t shstrtab_debug_frame_offset = shstrtab.size(); 276 shstrtab += ".debug_frame"; 277 shstrtab += '\0'; 278 uint32_t shstrtab_size = shstrtab.size(); 279 expected_offset += shstrtab_size; 280 if (debug) { 281 LOG(INFO) << "shstrtab_offset=" << shstrtab_offset << std::hex << " " << shstrtab_offset; 282 LOG(INFO) << "shstrtab_size=" << shstrtab_size << std::hex << " " << shstrtab_size; 283 } 284 285 // Create debug informatin, if we have it. 286 bool generateDebugInformation = compiler_driver_->GetCallFrameInformation() != nullptr; 287 std::vector<uint8_t> dbg_info; 288 std::vector<uint8_t> dbg_abbrev; 289 std::vector<uint8_t> dbg_str; 290 if (generateDebugInformation) { 291 FillInCFIInformation(oat_writer, &dbg_info, &dbg_abbrev, &dbg_str); 292 } 293 294 uint32_t shdbg_info_alignment = 1; 295 uint32_t shdbg_info_offset = expected_offset; 296 uint32_t shdbg_info_size = dbg_info.size(); 297 expected_offset += shdbg_info_size; 298 if (debug) { 299 LOG(INFO) << "shdbg_info_offset=" << shdbg_info_offset << std::hex << " " << shdbg_info_offset; 300 LOG(INFO) << "shdbg_info_size=" << shdbg_info_size << std::hex << " " << shdbg_info_size; 301 } 302 303 uint32_t shdbg_abbrev_alignment = 1; 304 uint32_t shdbg_abbrev_offset = expected_offset; 305 uint32_t shdbg_abbrev_size = dbg_abbrev.size(); 306 expected_offset += shdbg_abbrev_size; 307 if (debug) { 308 LOG(INFO) << "shdbg_abbrev_offset=" << shdbg_abbrev_offset << std::hex << " " << shdbg_abbrev_offset; 309 LOG(INFO) << "shdbg_abbrev_size=" << shdbg_abbrev_size << std::hex << " " << shdbg_abbrev_size; 310 } 311 312 uint32_t shdbg_frm_alignment = 4; 313 uint32_t shdbg_frm_offset = expected_offset = RoundUp(expected_offset, shdbg_frm_alignment); 314 uint32_t shdbg_frm_size = 315 generateDebugInformation ? compiler_driver_->GetCallFrameInformation()->size() : 0; 316 expected_offset += shdbg_frm_size; 317 if (debug) { 318 LOG(INFO) << "shdbg_frm_offset=" << shdbg_frm_offset << std::hex << " " << shdbg_frm_offset; 319 LOG(INFO) << "shdbg_frm_size=" << shdbg_frm_size << std::hex << " " << shdbg_frm_size; 320 } 321 322 uint32_t shdbg_str_alignment = 1; 323 uint32_t shdbg_str_offset = expected_offset; 324 uint32_t shdbg_str_size = dbg_str.size(); 325 expected_offset += shdbg_str_size; 326 if (debug) { 327 LOG(INFO) << "shdbg_str_offset=" << shdbg_str_offset << std::hex << " " << shdbg_str_offset; 328 LOG(INFO) << "shdbg_str_size=" << shdbg_str_size << std::hex << " " << shdbg_str_size; 329 } 330 331 // section headers (after all sections) 332 uint32_t shdr_alignment = sizeof(Elf32_Word); 333 uint32_t shdr_offset = expected_offset = RoundUp(expected_offset, shdr_alignment); 334 const uint8_t SH_NULL = 0; 335 const uint8_t SH_DYNSYM = 1; 336 const uint8_t SH_DYNSTR = 2; 337 const uint8_t SH_HASH = 3; 338 const uint8_t SH_RODATA = 4; 339 const uint8_t SH_TEXT = 5; 340 const uint8_t SH_DYNAMIC = 6; 341 const uint8_t SH_SHSTRTAB = 7; 342 const uint8_t SH_DBG_INFO = 8; 343 const uint8_t SH_DBG_ABRV = 9; 344 const uint8_t SH_DBG_FRM = 10; 345 const uint8_t SH_DBG_STR = 11; 346 const uint8_t SH_NUM = generateDebugInformation ? 12 : 8; 347 uint32_t shdr_size = sizeof(Elf32_Shdr) * SH_NUM; 348 expected_offset += shdr_size; 349 if (debug) { 350 LOG(INFO) << "shdr_offset=" << shdr_offset << std::hex << " " << shdr_offset; 351 LOG(INFO) << "shdr_size=" << shdr_size << std::hex << " " << shdr_size; 352 } 353 354 // phase 2: initializing data 355 356 // Elf32_Ehdr 357 Elf32_Ehdr elf_header; 358 memset(&elf_header, 0, sizeof(elf_header)); 359 elf_header.e_ident[EI_MAG0] = ELFMAG0; 360 elf_header.e_ident[EI_MAG1] = ELFMAG1; 361 elf_header.e_ident[EI_MAG2] = ELFMAG2; 362 elf_header.e_ident[EI_MAG3] = ELFMAG3; 363 elf_header.e_ident[EI_CLASS] = ELFCLASS32; 364 elf_header.e_ident[EI_DATA] = ELFDATA2LSB; 365 elf_header.e_ident[EI_VERSION] = EV_CURRENT; 366 elf_header.e_ident[EI_OSABI] = ELFOSABI_LINUX; 367 elf_header.e_ident[EI_ABIVERSION] = 0; 368 elf_header.e_type = ET_DYN; 369 switch (compiler_driver_->GetInstructionSet()) { 370 case kArm: 371 // Fall through. 372 case kThumb2: { 373 elf_header.e_machine = EM_ARM; 374 elf_header.e_flags = EF_ARM_EABI_VER5; 375 break; 376 } 377 case kArm64: { 378 elf_header.e_machine = EM_AARCH64; 379 elf_header.e_flags = 0; 380 break; 381 } 382 case kX86: { 383 elf_header.e_machine = EM_386; 384 elf_header.e_flags = 0; 385 break; 386 } 387 case kX86_64: { 388 elf_header.e_machine = EM_X86_64; 389 elf_header.e_flags = 0; 390 break; 391 } 392 case kMips: { 393 elf_header.e_machine = EM_MIPS; 394 elf_header.e_flags = (EF_MIPS_NOREORDER | 395 EF_MIPS_PIC | 396 EF_MIPS_CPIC | 397 EF_MIPS_ABI_O32 | 398 EF_MIPS_ARCH_32R2); 399 break; 400 } 401 default: { 402 LOG(FATAL) << "Unknown instruction set: " << compiler_driver_->GetInstructionSet(); 403 break; 404 } 405 } 406 elf_header.e_version = 1; 407 elf_header.e_entry = 0; 408 elf_header.e_phoff = phdr_offset; 409 elf_header.e_shoff = shdr_offset; 410 elf_header.e_ehsize = sizeof(Elf32_Ehdr); 411 elf_header.e_phentsize = sizeof(Elf32_Phdr); 412 elf_header.e_phnum = PH_NUM; 413 elf_header.e_shentsize = sizeof(Elf32_Shdr); 414 elf_header.e_shnum = SH_NUM; 415 elf_header.e_shstrndx = SH_SHSTRTAB; 416 417 // PHDR 418 Elf32_Phdr program_headers[PH_NUM]; 419 memset(&program_headers, 0, sizeof(program_headers)); 420 421 program_headers[PH_PHDR].p_type = PT_PHDR; 422 program_headers[PH_PHDR].p_offset = phdr_offset; 423 program_headers[PH_PHDR].p_vaddr = phdr_offset; 424 program_headers[PH_PHDR].p_paddr = phdr_offset; 425 program_headers[PH_PHDR].p_filesz = sizeof(program_headers); 426 program_headers[PH_PHDR].p_memsz = sizeof(program_headers); 427 program_headers[PH_PHDR].p_flags = PF_R; 428 program_headers[PH_PHDR].p_align = phdr_alignment; 429 430 program_headers[PH_LOAD_R__].p_type = PT_LOAD; 431 program_headers[PH_LOAD_R__].p_offset = 0; 432 program_headers[PH_LOAD_R__].p_vaddr = 0; 433 program_headers[PH_LOAD_R__].p_paddr = 0; 434 program_headers[PH_LOAD_R__].p_filesz = oat_data_offset + oat_data_size; 435 program_headers[PH_LOAD_R__].p_memsz = oat_data_offset + oat_data_size; 436 program_headers[PH_LOAD_R__].p_flags = PF_R; 437 program_headers[PH_LOAD_R__].p_align = oat_data_alignment; 438 439 program_headers[PH_LOAD_R_X].p_type = PT_LOAD; 440 program_headers[PH_LOAD_R_X].p_offset = oat_exec_offset; 441 program_headers[PH_LOAD_R_X].p_vaddr = oat_exec_offset; 442 program_headers[PH_LOAD_R_X].p_paddr = oat_exec_offset; 443 program_headers[PH_LOAD_R_X].p_filesz = oat_exec_size; 444 program_headers[PH_LOAD_R_X].p_memsz = oat_exec_size; 445 program_headers[PH_LOAD_R_X].p_flags = PF_R | PF_X; 446 program_headers[PH_LOAD_R_X].p_align = oat_exec_alignment; 447 448 // TODO: PF_W for DYNAMIC is considered processor specific, do we need it? 449 program_headers[PH_LOAD_RW_].p_type = PT_LOAD; 450 program_headers[PH_LOAD_RW_].p_offset = dynamic_offset; 451 program_headers[PH_LOAD_RW_].p_vaddr = dynamic_offset; 452 program_headers[PH_LOAD_RW_].p_paddr = dynamic_offset; 453 program_headers[PH_LOAD_RW_].p_filesz = dynamic_size; 454 program_headers[PH_LOAD_RW_].p_memsz = dynamic_size; 455 program_headers[PH_LOAD_RW_].p_flags = PF_R | PF_W; 456 program_headers[PH_LOAD_RW_].p_align = dynamic_alignment; 457 458 // TODO: PF_W for DYNAMIC is considered processor specific, do we need it? 459 program_headers[PH_DYNAMIC].p_type = PT_DYNAMIC; 460 program_headers[PH_DYNAMIC].p_offset = dynamic_offset; 461 program_headers[PH_DYNAMIC].p_vaddr = dynamic_offset; 462 program_headers[PH_DYNAMIC].p_paddr = dynamic_offset; 463 program_headers[PH_DYNAMIC].p_filesz = dynamic_size; 464 program_headers[PH_DYNAMIC].p_memsz = dynamic_size; 465 program_headers[PH_DYNAMIC].p_flags = PF_R | PF_W; 466 program_headers[PH_DYNAMIC].p_align = dynamic_alignment; 467 468 // .dynsym 469 Elf32_Sym dynsym[SYM_NUM]; 470 memset(&dynsym, 0, sizeof(dynsym)); 471 472 dynsym[SYM_UNDEF].st_name = 0; 473 dynsym[SYM_UNDEF].st_value = 0; 474 dynsym[SYM_UNDEF].st_size = 0; 475 dynsym[SYM_UNDEF].st_info = 0; 476 dynsym[SYM_UNDEF].st_other = 0; 477 dynsym[SYM_UNDEF].st_shndx = 0; 478 479 dynsym[SYM_OATDATA].st_name = dynstr_oatdata_offset; 480 dynsym[SYM_OATDATA].st_value = oat_data_offset; 481 dynsym[SYM_OATDATA].st_size = oat_data_size; 482 SetBindingAndType(&dynsym[SYM_OATDATA], STB_GLOBAL, STT_OBJECT); 483 dynsym[SYM_OATDATA].st_other = STV_DEFAULT; 484 dynsym[SYM_OATDATA].st_shndx = SH_RODATA; 485 486 dynsym[SYM_OATEXEC].st_name = dynstr_oatexec_offset; 487 dynsym[SYM_OATEXEC].st_value = oat_exec_offset; 488 dynsym[SYM_OATEXEC].st_size = oat_exec_size; 489 SetBindingAndType(&dynsym[SYM_OATEXEC], STB_GLOBAL, STT_OBJECT); 490 dynsym[SYM_OATEXEC].st_other = STV_DEFAULT; 491 dynsym[SYM_OATEXEC].st_shndx = SH_TEXT; 492 493 dynsym[SYM_OATLASTWORD].st_name = dynstr_oatlastword_offset; 494 dynsym[SYM_OATLASTWORD].st_value = oat_exec_offset + oat_exec_size - 4; 495 dynsym[SYM_OATLASTWORD].st_size = 4; 496 SetBindingAndType(&dynsym[SYM_OATLASTWORD], STB_GLOBAL, STT_OBJECT); 497 dynsym[SYM_OATLASTWORD].st_other = STV_DEFAULT; 498 dynsym[SYM_OATLASTWORD].st_shndx = SH_TEXT; 499 500 // .dynstr initialized above as dynstr 501 502 // .hash 503 Elf32_Word hash[HASH_NUM]; // Note this is Elf32_Word even on 64-bit 504 hash[HASH_NBUCKET] = 1; 505 hash[HASH_NCHAIN] = SYM_NUM; 506 hash[HASH_BUCKET0] = SYM_OATDATA; 507 hash[HASH_BUCKET0 + 1 + SYM_UNDEF] = SYM_UNDEF; 508 hash[HASH_BUCKET0 + 1 + SYM_OATDATA] = SYM_OATEXEC; 509 hash[HASH_BUCKET0 + 1 + SYM_OATEXEC] = SYM_OATLASTWORD; 510 hash[HASH_BUCKET0 + 1 + SYM_OATLASTWORD] = SYM_UNDEF; 511 512 // .rodata and .text content come from oat_contents 513 514 // .dynamic 515 Elf32_Dyn dynamic_headers[DH_NUM]; 516 memset(&dynamic_headers, 0, sizeof(dynamic_headers)); 517 518 dynamic_headers[DH_SONAME].d_tag = DT_SONAME; 519 dynamic_headers[DH_SONAME].d_un.d_val = dynstr_soname_offset; 520 521 dynamic_headers[DH_HASH].d_tag = DT_HASH; 522 dynamic_headers[DH_HASH].d_un.d_ptr = hash_offset; 523 524 dynamic_headers[DH_SYMTAB].d_tag = DT_SYMTAB; 525 dynamic_headers[DH_SYMTAB].d_un.d_ptr = dynsym_offset; 526 527 dynamic_headers[DH_SYMENT].d_tag = DT_SYMENT; 528 dynamic_headers[DH_SYMENT].d_un.d_val = sizeof(Elf32_Sym); 529 530 dynamic_headers[DH_STRTAB].d_tag = DT_STRTAB; 531 dynamic_headers[DH_STRTAB].d_un.d_ptr = dynstr_offset; 532 533 dynamic_headers[DH_STRSZ].d_tag = DT_STRSZ; 534 dynamic_headers[DH_STRSZ].d_un.d_val = dynstr_size; 535 536 dynamic_headers[DH_NULL].d_tag = DT_NULL; 537 dynamic_headers[DH_NULL].d_un.d_val = 0; 538 539 // .shstrtab initialized above as shstrtab 540 541 // section headers (after all sections) 542 Elf32_Shdr section_headers[SH_NUM]; 543 memset(§ion_headers, 0, sizeof(section_headers)); 544 545 section_headers[SH_NULL].sh_name = 0; 546 section_headers[SH_NULL].sh_type = SHT_NULL; 547 section_headers[SH_NULL].sh_flags = 0; 548 section_headers[SH_NULL].sh_addr = 0; 549 section_headers[SH_NULL].sh_offset = 0; 550 section_headers[SH_NULL].sh_size = 0; 551 section_headers[SH_NULL].sh_link = 0; 552 section_headers[SH_NULL].sh_info = 0; 553 section_headers[SH_NULL].sh_addralign = 0; 554 section_headers[SH_NULL].sh_entsize = 0; 555 556 section_headers[SH_DYNSYM].sh_name = shstrtab_dynsym_offset; 557 section_headers[SH_DYNSYM].sh_type = SHT_DYNSYM; 558 section_headers[SH_DYNSYM].sh_flags = SHF_ALLOC; 559 section_headers[SH_DYNSYM].sh_addr = dynsym_offset; 560 section_headers[SH_DYNSYM].sh_offset = dynsym_offset; 561 section_headers[SH_DYNSYM].sh_size = dynsym_size; 562 section_headers[SH_DYNSYM].sh_link = SH_DYNSTR; 563 section_headers[SH_DYNSYM].sh_info = 1; // 1 because we have not STB_LOCAL symbols 564 section_headers[SH_DYNSYM].sh_addralign = dynsym_alignment; 565 section_headers[SH_DYNSYM].sh_entsize = sizeof(Elf32_Sym); 566 567 section_headers[SH_DYNSTR].sh_name = shstrtab_dynstr_offset; 568 section_headers[SH_DYNSTR].sh_type = SHT_STRTAB; 569 section_headers[SH_DYNSTR].sh_flags = SHF_ALLOC; 570 section_headers[SH_DYNSTR].sh_addr = dynstr_offset; 571 section_headers[SH_DYNSTR].sh_offset = dynstr_offset; 572 section_headers[SH_DYNSTR].sh_size = dynstr_size; 573 section_headers[SH_DYNSTR].sh_link = 0; 574 section_headers[SH_DYNSTR].sh_info = 0; 575 section_headers[SH_DYNSTR].sh_addralign = dynstr_alignment; 576 section_headers[SH_DYNSTR].sh_entsize = 0; 577 578 section_headers[SH_HASH].sh_name = shstrtab_hash_offset; 579 section_headers[SH_HASH].sh_type = SHT_HASH; 580 section_headers[SH_HASH].sh_flags = SHF_ALLOC; 581 section_headers[SH_HASH].sh_addr = hash_offset; 582 section_headers[SH_HASH].sh_offset = hash_offset; 583 section_headers[SH_HASH].sh_size = hash_size; 584 section_headers[SH_HASH].sh_link = SH_DYNSYM; 585 section_headers[SH_HASH].sh_info = 0; 586 section_headers[SH_HASH].sh_addralign = hash_alignment; 587 section_headers[SH_HASH].sh_entsize = sizeof(Elf32_Word); // This is Elf32_Word even on 64-bit 588 589 section_headers[SH_RODATA].sh_name = shstrtab_rodata_offset; 590 section_headers[SH_RODATA].sh_type = SHT_PROGBITS; 591 section_headers[SH_RODATA].sh_flags = SHF_ALLOC; 592 section_headers[SH_RODATA].sh_addr = oat_data_offset; 593 section_headers[SH_RODATA].sh_offset = oat_data_offset; 594 section_headers[SH_RODATA].sh_size = oat_data_size; 595 section_headers[SH_RODATA].sh_link = 0; 596 section_headers[SH_RODATA].sh_info = 0; 597 section_headers[SH_RODATA].sh_addralign = oat_data_alignment; 598 section_headers[SH_RODATA].sh_entsize = 0; 599 600 section_headers[SH_TEXT].sh_name = shstrtab_text_offset; 601 section_headers[SH_TEXT].sh_type = SHT_PROGBITS; 602 section_headers[SH_TEXT].sh_flags = SHF_ALLOC | SHF_EXECINSTR; 603 section_headers[SH_TEXT].sh_addr = oat_exec_offset; 604 section_headers[SH_TEXT].sh_offset = oat_exec_offset; 605 section_headers[SH_TEXT].sh_size = oat_exec_size; 606 section_headers[SH_TEXT].sh_link = 0; 607 section_headers[SH_TEXT].sh_info = 0; 608 section_headers[SH_TEXT].sh_addralign = oat_exec_alignment; 609 section_headers[SH_TEXT].sh_entsize = 0; 610 611 // TODO: SHF_WRITE for .dynamic is considered processor specific, do we need it? 612 section_headers[SH_DYNAMIC].sh_name = shstrtab_dynamic_offset; 613 section_headers[SH_DYNAMIC].sh_type = SHT_DYNAMIC; 614 section_headers[SH_DYNAMIC].sh_flags = SHF_WRITE | SHF_ALLOC; 615 section_headers[SH_DYNAMIC].sh_addr = dynamic_offset; 616 section_headers[SH_DYNAMIC].sh_offset = dynamic_offset; 617 section_headers[SH_DYNAMIC].sh_size = dynamic_size; 618 section_headers[SH_DYNAMIC].sh_link = SH_DYNSTR; 619 section_headers[SH_DYNAMIC].sh_info = 0; 620 section_headers[SH_DYNAMIC].sh_addralign = dynamic_alignment; 621 section_headers[SH_DYNAMIC].sh_entsize = sizeof(Elf32_Dyn); 622 623 section_headers[SH_SHSTRTAB].sh_name = shstrtab_shstrtab_offset; 624 section_headers[SH_SHSTRTAB].sh_type = SHT_STRTAB; 625 section_headers[SH_SHSTRTAB].sh_flags = 0; 626 section_headers[SH_SHSTRTAB].sh_addr = shstrtab_offset; 627 section_headers[SH_SHSTRTAB].sh_offset = shstrtab_offset; 628 section_headers[SH_SHSTRTAB].sh_size = shstrtab_size; 629 section_headers[SH_SHSTRTAB].sh_link = 0; 630 section_headers[SH_SHSTRTAB].sh_info = 0; 631 section_headers[SH_SHSTRTAB].sh_addralign = shstrtab_alignment; 632 section_headers[SH_SHSTRTAB].sh_entsize = 0; 633 634 if (generateDebugInformation) { 635 section_headers[SH_DBG_INFO].sh_name = shstrtab_debug_info_offset; 636 section_headers[SH_DBG_INFO].sh_type = SHT_PROGBITS; 637 section_headers[SH_DBG_INFO].sh_flags = 0; 638 section_headers[SH_DBG_INFO].sh_addr = 0; 639 section_headers[SH_DBG_INFO].sh_offset = shdbg_info_offset; 640 section_headers[SH_DBG_INFO].sh_size = shdbg_info_size; 641 section_headers[SH_DBG_INFO].sh_link = 0; 642 section_headers[SH_DBG_INFO].sh_info = 0; 643 section_headers[SH_DBG_INFO].sh_addralign = shdbg_info_alignment; 644 section_headers[SH_DBG_INFO].sh_entsize = 0; 645 646 section_headers[SH_DBG_ABRV].sh_name = shstrtab_debug_abbrev_offset; 647 section_headers[SH_DBG_ABRV].sh_type = SHT_PROGBITS; 648 section_headers[SH_DBG_ABRV].sh_flags = 0; 649 section_headers[SH_DBG_ABRV].sh_addr = 0; 650 section_headers[SH_DBG_ABRV].sh_offset = shdbg_abbrev_offset; 651 section_headers[SH_DBG_ABRV].sh_size = shdbg_abbrev_size; 652 section_headers[SH_DBG_ABRV].sh_link = 0; 653 section_headers[SH_DBG_ABRV].sh_info = 0; 654 section_headers[SH_DBG_ABRV].sh_addralign = shdbg_abbrev_alignment; 655 section_headers[SH_DBG_ABRV].sh_entsize = 0; 656 657 section_headers[SH_DBG_FRM].sh_name = shstrtab_debug_frame_offset; 658 section_headers[SH_DBG_FRM].sh_type = SHT_PROGBITS; 659 section_headers[SH_DBG_FRM].sh_flags = 0; 660 section_headers[SH_DBG_FRM].sh_addr = 0; 661 section_headers[SH_DBG_FRM].sh_offset = shdbg_frm_offset; 662 section_headers[SH_DBG_FRM].sh_size = shdbg_frm_size; 663 section_headers[SH_DBG_FRM].sh_link = 0; 664 section_headers[SH_DBG_FRM].sh_info = 0; 665 section_headers[SH_DBG_FRM].sh_addralign = shdbg_frm_alignment; 666 section_headers[SH_DBG_FRM].sh_entsize = 0; 667 668 section_headers[SH_DBG_STR].sh_name = shstrtab_debug_str_offset; 669 section_headers[SH_DBG_STR].sh_type = SHT_PROGBITS; 670 section_headers[SH_DBG_STR].sh_flags = 0; 671 section_headers[SH_DBG_STR].sh_addr = 0; 672 section_headers[SH_DBG_STR].sh_offset = shdbg_str_offset; 673 section_headers[SH_DBG_STR].sh_size = shdbg_str_size; 674 section_headers[SH_DBG_STR].sh_link = 0; 675 section_headers[SH_DBG_STR].sh_info = 0; 676 section_headers[SH_DBG_STR].sh_addralign = shdbg_str_alignment; 677 section_headers[SH_DBG_STR].sh_entsize = 0; 678 } 679 680 // phase 3: writing file 681 682 // Elf32_Ehdr 683 if (!elf_file_->WriteFully(&elf_header, sizeof(elf_header))) { 684 PLOG(ERROR) << "Failed to write ELF header for " << elf_file_->GetPath(); 685 return false; 686 } 687 688 // PHDR 689 if (static_cast<off_t>(phdr_offset) != lseek(elf_file_->Fd(), 0, SEEK_CUR)) { 690 PLOG(ERROR) << "Failed to be at expected ELF program header offset phdr_offset " 691 << " for " << elf_file_->GetPath(); 692 return false; 693 } 694 if (!elf_file_->WriteFully(program_headers, sizeof(program_headers))) { 695 PLOG(ERROR) << "Failed to write ELF program headers for " << elf_file_->GetPath(); 696 return false; 697 } 698 699 // .dynsym 700 DCHECK_LE(phdr_offset + phdr_size, dynsym_offset); 701 if (static_cast<off_t>(dynsym_offset) != lseek(elf_file_->Fd(), dynsym_offset, SEEK_SET)) { 702 PLOG(ERROR) << "Failed to seek to .dynsym offset location " << dynsym_offset 703 << " for " << elf_file_->GetPath(); 704 return false; 705 } 706 if (!elf_file_->WriteFully(dynsym, sizeof(dynsym))) { 707 PLOG(ERROR) << "Failed to write .dynsym for " << elf_file_->GetPath(); 708 return false; 709 } 710 711 // .dynstr 712 DCHECK_LE(dynsym_offset + dynsym_size, dynstr_offset); 713 if (static_cast<off_t>(dynstr_offset) != lseek(elf_file_->Fd(), dynstr_offset, SEEK_SET)) { 714 PLOG(ERROR) << "Failed to seek to .dynstr offset " << dynstr_offset 715 << " for " << elf_file_->GetPath(); 716 return false; 717 } 718 if (!elf_file_->WriteFully(&dynstr[0], dynstr_size)) { 719 PLOG(ERROR) << "Failed to write .dynsym for " << elf_file_->GetPath(); 720 return false; 721 } 722 723 // .hash 724 DCHECK_LE(dynstr_offset + dynstr_size, hash_offset); 725 if (static_cast<off_t>(hash_offset) != lseek(elf_file_->Fd(), hash_offset, SEEK_SET)) { 726 PLOG(ERROR) << "Failed to seek to .hash offset " << hash_offset 727 << " for " << elf_file_->GetPath(); 728 return false; 729 } 730 if (!elf_file_->WriteFully(hash, sizeof(hash))) { 731 PLOG(ERROR) << "Failed to write .dynsym for " << elf_file_->GetPath(); 732 return false; 733 } 734 735 // .rodata .text 736 DCHECK_LE(hash_offset + hash_size, oat_data_offset); 737 if (static_cast<off_t>(oat_data_offset) != lseek(elf_file_->Fd(), oat_data_offset, SEEK_SET)) { 738 PLOG(ERROR) << "Failed to seek to .rodata offset " << oat_data_offset 739 << " for " << elf_file_->GetPath(); 740 return false; 741 } 742 BufferedOutputStream output_stream(new FileOutputStream(elf_file_)); 743 if (!oat_writer->Write(&output_stream)) { 744 PLOG(ERROR) << "Failed to write .rodata and .text for " << elf_file_->GetPath(); 745 return false; 746 } 747 748 // .dynamic 749 DCHECK_LE(oat_data_offset + oat_writer->GetSize(), dynamic_offset); 750 if (static_cast<off_t>(dynamic_offset) != lseek(elf_file_->Fd(), dynamic_offset, SEEK_SET)) { 751 PLOG(ERROR) << "Failed to seek to .dynamic offset " << dynamic_offset 752 << " for " << elf_file_->GetPath(); 753 return false; 754 } 755 if (!elf_file_->WriteFully(&dynamic_headers[0], dynamic_size)) { 756 PLOG(ERROR) << "Failed to write .dynamic for " << elf_file_->GetPath(); 757 return false; 758 } 759 760 // .shstrtab 761 DCHECK_LE(dynamic_offset + dynamic_size, shstrtab_offset); 762 if (static_cast<off_t>(shstrtab_offset) != lseek(elf_file_->Fd(), shstrtab_offset, SEEK_SET)) { 763 PLOG(ERROR) << "Failed to seek to .shstrtab offset " << shstrtab_offset 764 << " for " << elf_file_->GetPath(); 765 return false; 766 } 767 if (!elf_file_->WriteFully(&shstrtab[0], shstrtab_size)) { 768 PLOG(ERROR) << "Failed to write .shstrtab for " << elf_file_->GetPath(); 769 return false; 770 } 771 772 if (generateDebugInformation) { 773 // .debug_info 774 DCHECK_LE(shstrtab_offset + shstrtab_size, shdbg_info_offset); 775 if (static_cast<off_t>(shdbg_info_offset) != lseek(elf_file_->Fd(), shdbg_info_offset, SEEK_SET)) { 776 PLOG(ERROR) << "Failed to seek to .shdbg_info offset " << shdbg_info_offset 777 << " for " << elf_file_->GetPath(); 778 return false; 779 } 780 if (!elf_file_->WriteFully(&dbg_info[0], shdbg_info_size)) { 781 PLOG(ERROR) << "Failed to write .debug_info for " << elf_file_->GetPath(); 782 return false; 783 } 784 785 // .debug_abbrev 786 DCHECK_LE(shdbg_info_offset + shdbg_info_size, shdbg_abbrev_offset); 787 if (static_cast<off_t>(shdbg_abbrev_offset) != lseek(elf_file_->Fd(), shdbg_abbrev_offset, SEEK_SET)) { 788 PLOG(ERROR) << "Failed to seek to .shdbg_abbrev offset " << shdbg_abbrev_offset 789 << " for " << elf_file_->GetPath(); 790 return false; 791 } 792 if (!elf_file_->WriteFully(&dbg_abbrev[0], shdbg_abbrev_size)) { 793 PLOG(ERROR) << "Failed to write .debug_abbrev for " << elf_file_->GetPath(); 794 return false; 795 } 796 797 // .debug_frame 798 DCHECK_LE(shdbg_abbrev_offset + shdbg_abbrev_size, shdbg_frm_offset); 799 if (static_cast<off_t>(shdbg_frm_offset) != lseek(elf_file_->Fd(), shdbg_frm_offset, SEEK_SET)) { 800 PLOG(ERROR) << "Failed to seek to .shdbg_frm offset " << shdbg_frm_offset 801 << " for " << elf_file_->GetPath(); 802 return false; 803 } 804 if (!elf_file_->WriteFully(&((*compiler_driver_->GetCallFrameInformation())[0]), shdbg_frm_size)) { 805 PLOG(ERROR) << "Failed to write .debug_frame for " << elf_file_->GetPath(); 806 return false; 807 } 808 809 // .debug_str 810 DCHECK_LE(shdbg_frm_offset + shdbg_frm_size, shdbg_str_offset); 811 if (static_cast<off_t>(shdbg_str_offset) != lseek(elf_file_->Fd(), shdbg_str_offset, SEEK_SET)) { 812 PLOG(ERROR) << "Failed to seek to .shdbg_str offset " << shdbg_str_offset 813 << " for " << elf_file_->GetPath(); 814 return false; 815 } 816 if (!elf_file_->WriteFully(&dbg_str[0], shdbg_str_size)) { 817 PLOG(ERROR) << "Failed to write .debug_frame for " << elf_file_->GetPath(); 818 return false; 819 } 820 } 821 822 // section headers (after all sections) 823 if (generateDebugInformation) { 824 DCHECK_LE(shdbg_str_offset + shdbg_str_size, shdr_offset); 825 } else { 826 DCHECK_LE(shstrtab_offset + shstrtab_size, shdr_offset); 827 } 828 if (static_cast<off_t>(shdr_offset) != lseek(elf_file_->Fd(), shdr_offset, SEEK_SET)) { 829 PLOG(ERROR) << "Failed to seek to ELF section headers offset " << shdr_offset 830 << " for " << elf_file_->GetPath(); 831 return false; 832 } 833 if (!elf_file_->WriteFully(section_headers, sizeof(section_headers))) { 834 PLOG(ERROR) << "Failed to write ELF section headers for " << elf_file_->GetPath(); 835 return false; 836 } 837 838 VLOG(compiler) << "ELF file written successfully: " << elf_file_->GetPath(); 839 return true; 840} // NOLINT(readability/fn_size) 841 842static void UpdateWord(std::vector<uint8_t>*buf, int offset, int data) { 843 (*buf)[offset+0] = data; 844 (*buf)[offset+1] = data >> 8; 845 (*buf)[offset+2] = data >> 16; 846 (*buf)[offset+3] = data >> 24; 847} 848 849static void PushWord(std::vector<uint8_t>*buf, int data) { 850 buf->push_back(data & 0xff); 851 buf->push_back((data >> 8) & 0xff); 852 buf->push_back((data >> 16) & 0xff); 853 buf->push_back((data >> 24) & 0xff); 854} 855 856static void PushHalf(std::vector<uint8_t>*buf, int data) { 857 buf->push_back(data & 0xff); 858 buf->push_back((data >> 8) & 0xff); 859} 860 861// DWARF constants needed to generate CFI information. 862enum { 863 // Tag encodings. 864 DW_TAG_compile_unit = 0x11, 865 DW_TAG_subprogram = 0X2e, 866 867 // Attribute encodings. 868 DW_AT_name = 0x03, 869 DW_AT_low_pc = 0x11, 870 DW_AT_high_pc = 0x12, 871 DW_AT_language = 0x13, 872 873 // Constant encoding. 874 DW_CHILDREN_no = 0x00, 875 DW_CHILDREN_yes = 0x01, 876 877 // Attribute form encodings. 878 DW_FORM_addr = 0x01, 879 DW_FORM_data1 = 0x0b, 880 DW_FORM_strp = 0x0e, 881 882 // Language encoding. 883 DW_LANG_Java = 0x000b 884}; 885 886void ElfWriterQuick::FillInCFIInformation(OatWriter* oat_writer, 887 std::vector<uint8_t>* dbg_info, 888 std::vector<uint8_t>* dbg_abbrev, 889 std::vector<uint8_t>* dbg_str) { 890 // Create the debug_abbrev section with boilerplate information. 891 // We only care about low_pc and high_pc right now for the compilation 892 // unit and methods. 893 894 // Tag 1: Compilation unit: DW_TAG_compile_unit. 895 dbg_abbrev->push_back(1); 896 dbg_abbrev->push_back(DW_TAG_compile_unit); 897 898 // There are children (the methods). 899 dbg_abbrev->push_back(DW_CHILDREN_yes); 900 901 // DW_LANG_Java DW_FORM_data1. 902 dbg_abbrev->push_back(DW_AT_language); 903 dbg_abbrev->push_back(DW_FORM_data1); 904 905 // DW_AT_low_pc DW_FORM_addr. 906 dbg_abbrev->push_back(DW_AT_low_pc); 907 dbg_abbrev->push_back(DW_FORM_addr); 908 909 // DW_AT_high_pc DW_FORM_addr. 910 dbg_abbrev->push_back(DW_AT_high_pc); 911 dbg_abbrev->push_back(DW_FORM_addr); 912 913 // End of DW_TAG_compile_unit. 914 PushHalf(dbg_abbrev, 0); 915 916 // Tag 2: Compilation unit: DW_TAG_subprogram. 917 dbg_abbrev->push_back(2); 918 dbg_abbrev->push_back(DW_TAG_subprogram); 919 920 // There are no children. 921 dbg_abbrev->push_back(DW_CHILDREN_no); 922 923 // Name of the method. 924 dbg_abbrev->push_back(DW_AT_name); 925 dbg_abbrev->push_back(DW_FORM_strp); 926 927 // DW_AT_low_pc DW_FORM_addr. 928 dbg_abbrev->push_back(DW_AT_low_pc); 929 dbg_abbrev->push_back(DW_FORM_addr); 930 931 // DW_AT_high_pc DW_FORM_addr. 932 dbg_abbrev->push_back(DW_AT_high_pc); 933 dbg_abbrev->push_back(DW_FORM_addr); 934 935 // End of DW_TAG_subprogram. 936 PushHalf(dbg_abbrev, 0); 937 938 // Start the debug_info section with the header information 939 // 'unit_length' will be filled in later. 940 PushWord(dbg_info, 0); 941 942 // 'version' - 3. 943 PushHalf(dbg_info, 3); 944 945 // Offset into .debug_abbrev section (always 0). 946 PushWord(dbg_info, 0); 947 948 // Address size: 4. 949 dbg_info->push_back(4); 950 951 // Start the description for the compilation unit. 952 // This uses tag 1. 953 dbg_info->push_back(1); 954 955 // The language is Java. 956 dbg_info->push_back(DW_LANG_Java); 957 958 // Leave space for low_pc and high_pc. 959 int low_pc_offset = dbg_info->size(); 960 PushWord(dbg_info, 0); 961 PushWord(dbg_info, 0); 962 963 // Walk through the information in the method table, and enter into dbg_info. 964 const std::vector<OatWriter::DebugInfo>& dbg = oat_writer->GetCFIMethodInfo(); 965 uint32_t low_pc = 0xFFFFFFFFU; 966 uint32_t high_pc = 0; 967 968 for (uint32_t i = 0; i < dbg.size(); i++) { 969 const OatWriter::DebugInfo& info = dbg[i]; 970 if (info.low_pc_ < low_pc) { 971 low_pc = info.low_pc_; 972 } 973 if (info.high_pc_ > high_pc) { 974 high_pc = info.high_pc_; 975 } 976 977 // Start a new TAG: subroutine (2). 978 dbg_info->push_back(2); 979 980 // Enter the name into the string table (and NUL terminate). 981 uint32_t str_offset = dbg_str->size(); 982 dbg_str->insert(dbg_str->end(), info.method_name_.begin(), info.method_name_.end()); 983 dbg_str->push_back('\0'); 984 985 // Enter name, low_pc, high_pc. 986 PushWord(dbg_info, str_offset); 987 PushWord(dbg_info, info.low_pc_); 988 PushWord(dbg_info, info.high_pc_); 989 } 990 991 // One byte terminator 992 dbg_info->push_back(0); 993 994 // We have now walked all the methods. Fill in lengths and low/high PCs. 995 UpdateWord(dbg_info, 0, dbg_info->size() - 4); 996 UpdateWord(dbg_info, low_pc_offset, low_pc); 997 UpdateWord(dbg_info, low_pc_offset + 4, high_pc); 998} 999 1000} // namespace art 1001