Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 1 | //===--------------------------- DwarfParser.hpp --------------------------===// |
| 2 | // |
| 3 | // The LLVM Compiler Infrastructure |
| 4 | // |
| 5 | // This file is dual licensed under the MIT and the University of Illinois Open |
| 6 | // Source Licenses. See LICENSE.TXT for details. |
| 7 | // |
| 8 | // |
| 9 | // Parses DWARF CFIs (FDEs and CIEs). |
| 10 | // |
| 11 | //===----------------------------------------------------------------------===// |
| 12 | |
| 13 | #ifndef __DWARF_PARSER_HPP__ |
| 14 | #define __DWARF_PARSER_HPP__ |
| 15 | |
| 16 | #include <inttypes.h> |
| 17 | #include <stdint.h> |
| 18 | #include <stdio.h> |
| 19 | #include <stdlib.h> |
| 20 | |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 21 | #include "libunwind.h" |
| 22 | #include "dwarf2.h" |
| 23 | |
| 24 | #include "AddressSpace.hpp" |
| 25 | |
| 26 | namespace libunwind { |
| 27 | |
| 28 | /// CFI_Parser does basic parsing of a CFI (Call Frame Information) records. |
Ed Maste | 63469ff | 2016-07-19 17:15:50 +0000 | [diff] [blame] | 29 | /// See DWARF Spec for details: |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 30 | /// http://refspecs.linuxbase.org/LSB_3.1.0/LSB-Core-generic/LSB-Core-generic/ehframechpt.html |
| 31 | /// |
| 32 | template <typename A> |
| 33 | class CFI_Parser { |
| 34 | public: |
| 35 | typedef typename A::pint_t pint_t; |
| 36 | |
| 37 | /// Information encoded in a CIE (Common Information Entry) |
| 38 | struct CIE_Info { |
| 39 | pint_t cieStart; |
| 40 | pint_t cieLength; |
| 41 | pint_t cieInstructions; |
| 42 | uint8_t pointerEncoding; |
| 43 | uint8_t lsdaEncoding; |
| 44 | uint8_t personalityEncoding; |
| 45 | uint8_t personalityOffsetInCIE; |
| 46 | pint_t personality; |
| 47 | uint32_t codeAlignFactor; |
| 48 | int dataAlignFactor; |
| 49 | bool isSignalFrame; |
| 50 | bool fdesHaveAugmentationData; |
| 51 | uint8_t returnAddressRegister; |
| 52 | }; |
| 53 | |
| 54 | /// Information about an FDE (Frame Description Entry) |
| 55 | struct FDE_Info { |
| 56 | pint_t fdeStart; |
| 57 | pint_t fdeLength; |
| 58 | pint_t fdeInstructions; |
| 59 | pint_t pcStart; |
| 60 | pint_t pcEnd; |
| 61 | pint_t lsda; |
| 62 | }; |
| 63 | |
| 64 | enum { |
Ed Maste | f9f7928 | 2016-07-20 15:19:09 +0000 | [diff] [blame] | 65 | kMaxRegisterNumber = _LIBUNWIND_HIGHEST_DWARF_REGISTER |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 66 | }; |
| 67 | enum RegisterSavedWhere { |
| 68 | kRegisterUnused, |
| 69 | kRegisterInCFA, |
| 70 | kRegisterOffsetFromCFA, |
| 71 | kRegisterInRegister, |
| 72 | kRegisterAtExpression, |
| 73 | kRegisterIsExpression |
| 74 | }; |
| 75 | struct RegisterLocation { |
| 76 | RegisterSavedWhere location; |
| 77 | int64_t value; |
| 78 | }; |
| 79 | /// Information about a frame layout and registers saved determined |
Ed Maste | 63469ff | 2016-07-19 17:15:50 +0000 | [diff] [blame] | 80 | /// by "running" the DWARF FDE "instructions" |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 81 | struct PrologInfo { |
| 82 | uint32_t cfaRegister; |
| 83 | int32_t cfaRegisterOffset; // CFA = (cfaRegister)+cfaRegisterOffset |
| 84 | int64_t cfaExpression; // CFA = expression |
| 85 | uint32_t spExtraArgSize; |
| 86 | uint32_t codeOffsetAtStackDecrement; |
| 87 | bool registersInOtherRegisters; |
| 88 | bool sameValueUsed; |
| 89 | RegisterLocation savedRegisters[kMaxRegisterNumber]; |
| 90 | }; |
| 91 | |
| 92 | struct PrologInfoStackEntry { |
| 93 | PrologInfoStackEntry(PrologInfoStackEntry *n, const PrologInfo &i) |
| 94 | : next(n), info(i) {} |
| 95 | PrologInfoStackEntry *next; |
| 96 | PrologInfo info; |
| 97 | }; |
| 98 | |
| 99 | static bool findFDE(A &addressSpace, pint_t pc, pint_t ehSectionStart, |
| 100 | uint32_t sectionLength, pint_t fdeHint, FDE_Info *fdeInfo, |
| 101 | CIE_Info *cieInfo); |
| 102 | static const char *decodeFDE(A &addressSpace, pint_t fdeStart, |
| 103 | FDE_Info *fdeInfo, CIE_Info *cieInfo); |
| 104 | static bool parseFDEInstructions(A &addressSpace, const FDE_Info &fdeInfo, |
| 105 | const CIE_Info &cieInfo, pint_t upToPC, |
| 106 | PrologInfo *results); |
| 107 | |
| 108 | static const char *parseCIE(A &addressSpace, pint_t cie, CIE_Info *cieInfo); |
| 109 | |
| 110 | private: |
| 111 | static bool parseInstructions(A &addressSpace, pint_t instructions, |
| 112 | pint_t instructionsEnd, const CIE_Info &cieInfo, |
| 113 | pint_t pcoffset, |
| 114 | PrologInfoStackEntry *&rememberStack, |
| 115 | PrologInfo *results); |
| 116 | }; |
| 117 | |
| 118 | /// Parse a FDE into a CIE_Info and an FDE_Info |
| 119 | template <typename A> |
| 120 | const char *CFI_Parser<A>::decodeFDE(A &addressSpace, pint_t fdeStart, |
| 121 | FDE_Info *fdeInfo, CIE_Info *cieInfo) { |
| 122 | pint_t p = fdeStart; |
| 123 | pint_t cfiLength = (pint_t)addressSpace.get32(p); |
| 124 | p += 4; |
| 125 | if (cfiLength == 0xffffffff) { |
| 126 | // 0xffffffff means length is really next 8 bytes |
| 127 | cfiLength = (pint_t)addressSpace.get64(p); |
| 128 | p += 8; |
| 129 | } |
| 130 | if (cfiLength == 0) |
| 131 | return "FDE has zero length"; // end marker |
| 132 | uint32_t ciePointer = addressSpace.get32(p); |
| 133 | if (ciePointer == 0) |
| 134 | return "FDE is really a CIE"; // this is a CIE not an FDE |
| 135 | pint_t nextCFI = p + cfiLength; |
| 136 | pint_t cieStart = p - ciePointer; |
| 137 | const char *err = parseCIE(addressSpace, cieStart, cieInfo); |
| 138 | if (err != NULL) |
| 139 | return err; |
| 140 | p += 4; |
Ed Maste | 9de42aa | 2016-07-19 17:28:38 +0000 | [diff] [blame] | 141 | // Parse pc begin and range. |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 142 | pint_t pcStart = |
| 143 | addressSpace.getEncodedP(p, nextCFI, cieInfo->pointerEncoding); |
| 144 | pint_t pcRange = |
| 145 | addressSpace.getEncodedP(p, nextCFI, cieInfo->pointerEncoding & 0x0F); |
Ed Maste | 9de42aa | 2016-07-19 17:28:38 +0000 | [diff] [blame] | 146 | // Parse rest of info. |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 147 | fdeInfo->lsda = 0; |
Ed Maste | 9de42aa | 2016-07-19 17:28:38 +0000 | [diff] [blame] | 148 | // Check for augmentation length. |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 149 | if (cieInfo->fdesHaveAugmentationData) { |
| 150 | pint_t augLen = (pint_t)addressSpace.getULEB128(p, nextCFI); |
| 151 | pint_t endOfAug = p + augLen; |
| 152 | if (cieInfo->lsdaEncoding != DW_EH_PE_omit) { |
Ed Maste | 9de42aa | 2016-07-19 17:28:38 +0000 | [diff] [blame] | 153 | // Peek at value (without indirection). Zero means no LSDA. |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 154 | pint_t lsdaStart = p; |
| 155 | if (addressSpace.getEncodedP(p, nextCFI, cieInfo->lsdaEncoding & 0x0F) != |
| 156 | 0) { |
Ed Maste | 9de42aa | 2016-07-19 17:28:38 +0000 | [diff] [blame] | 157 | // Reset pointer and re-parse LSDA address. |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 158 | p = lsdaStart; |
| 159 | fdeInfo->lsda = |
| 160 | addressSpace.getEncodedP(p, nextCFI, cieInfo->lsdaEncoding); |
| 161 | } |
| 162 | } |
| 163 | p = endOfAug; |
| 164 | } |
| 165 | fdeInfo->fdeStart = fdeStart; |
| 166 | fdeInfo->fdeLength = nextCFI - fdeStart; |
| 167 | fdeInfo->fdeInstructions = p; |
| 168 | fdeInfo->pcStart = pcStart; |
| 169 | fdeInfo->pcEnd = pcStart + pcRange; |
| 170 | return NULL; // success |
| 171 | } |
| 172 | |
| 173 | /// Scan an eh_frame section to find an FDE for a pc |
| 174 | template <typename A> |
| 175 | bool CFI_Parser<A>::findFDE(A &addressSpace, pint_t pc, pint_t ehSectionStart, |
| 176 | uint32_t sectionLength, pint_t fdeHint, |
| 177 | FDE_Info *fdeInfo, CIE_Info *cieInfo) { |
| 178 | //fprintf(stderr, "findFDE(0x%llX)\n", (long long)pc); |
| 179 | pint_t p = (fdeHint != 0) ? fdeHint : ehSectionStart; |
| 180 | const pint_t ehSectionEnd = p + sectionLength; |
| 181 | while (p < ehSectionEnd) { |
| 182 | pint_t currentCFI = p; |
| 183 | //fprintf(stderr, "findFDE() CFI at 0x%llX\n", (long long)p); |
| 184 | pint_t cfiLength = addressSpace.get32(p); |
| 185 | p += 4; |
| 186 | if (cfiLength == 0xffffffff) { |
| 187 | // 0xffffffff means length is really next 8 bytes |
| 188 | cfiLength = (pint_t)addressSpace.get64(p); |
| 189 | p += 8; |
| 190 | } |
| 191 | if (cfiLength == 0) |
| 192 | return false; // end marker |
| 193 | uint32_t id = addressSpace.get32(p); |
| 194 | if (id == 0) { |
Ed Maste | 9de42aa | 2016-07-19 17:28:38 +0000 | [diff] [blame] | 195 | // Skip over CIEs. |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 196 | p += cfiLength; |
| 197 | } else { |
Ed Maste | 9de42aa | 2016-07-19 17:28:38 +0000 | [diff] [blame] | 198 | // Process FDE to see if it covers pc. |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 199 | pint_t nextCFI = p + cfiLength; |
| 200 | uint32_t ciePointer = addressSpace.get32(p); |
| 201 | pint_t cieStart = p - ciePointer; |
Ed Maste | 9de42aa | 2016-07-19 17:28:38 +0000 | [diff] [blame] | 202 | // Validate pointer to CIE is within section. |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 203 | if ((ehSectionStart <= cieStart) && (cieStart < ehSectionEnd)) { |
| 204 | if (parseCIE(addressSpace, cieStart, cieInfo) == NULL) { |
| 205 | p += 4; |
Ed Maste | 9de42aa | 2016-07-19 17:28:38 +0000 | [diff] [blame] | 206 | // Parse pc begin and range. |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 207 | pint_t pcStart = |
| 208 | addressSpace.getEncodedP(p, nextCFI, cieInfo->pointerEncoding); |
| 209 | pint_t pcRange = addressSpace.getEncodedP( |
| 210 | p, nextCFI, cieInfo->pointerEncoding & 0x0F); |
Ed Maste | 9de42aa | 2016-07-19 17:28:38 +0000 | [diff] [blame] | 211 | // Test if pc is within the function this FDE covers. |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 212 | if ((pcStart < pc) && (pc <= pcStart + pcRange)) { |
| 213 | // parse rest of info |
| 214 | fdeInfo->lsda = 0; |
| 215 | // check for augmentation length |
| 216 | if (cieInfo->fdesHaveAugmentationData) { |
| 217 | pint_t augLen = (pint_t)addressSpace.getULEB128(p, nextCFI); |
| 218 | pint_t endOfAug = p + augLen; |
| 219 | if (cieInfo->lsdaEncoding != DW_EH_PE_omit) { |
Ed Maste | 9de42aa | 2016-07-19 17:28:38 +0000 | [diff] [blame] | 220 | // Peek at value (without indirection). Zero means no LSDA. |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 221 | pint_t lsdaStart = p; |
| 222 | if (addressSpace.getEncodedP( |
| 223 | p, nextCFI, cieInfo->lsdaEncoding & 0x0F) != 0) { |
Ed Maste | 9de42aa | 2016-07-19 17:28:38 +0000 | [diff] [blame] | 224 | // Reset pointer and re-parse LSDA address. |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 225 | p = lsdaStart; |
| 226 | fdeInfo->lsda = addressSpace |
| 227 | .getEncodedP(p, nextCFI, cieInfo->lsdaEncoding); |
| 228 | } |
| 229 | } |
| 230 | p = endOfAug; |
| 231 | } |
| 232 | fdeInfo->fdeStart = currentCFI; |
| 233 | fdeInfo->fdeLength = nextCFI - currentCFI; |
| 234 | fdeInfo->fdeInstructions = p; |
| 235 | fdeInfo->pcStart = pcStart; |
| 236 | fdeInfo->pcEnd = pcStart + pcRange; |
| 237 | return true; |
| 238 | } else { |
| 239 | // pc is not in begin/range, skip this FDE |
| 240 | } |
| 241 | } else { |
Ed Maste | 9de42aa | 2016-07-19 17:28:38 +0000 | [diff] [blame] | 242 | // Malformed CIE, now augmentation describing pc range encoding. |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 243 | } |
| 244 | } else { |
| 245 | // malformed FDE. CIE is bad |
| 246 | } |
| 247 | p = nextCFI; |
| 248 | } |
| 249 | } |
| 250 | return false; |
| 251 | } |
| 252 | |
| 253 | /// Extract info from a CIE |
| 254 | template <typename A> |
| 255 | const char *CFI_Parser<A>::parseCIE(A &addressSpace, pint_t cie, |
| 256 | CIE_Info *cieInfo) { |
| 257 | cieInfo->pointerEncoding = 0; |
| 258 | cieInfo->lsdaEncoding = DW_EH_PE_omit; |
| 259 | cieInfo->personalityEncoding = 0; |
| 260 | cieInfo->personalityOffsetInCIE = 0; |
| 261 | cieInfo->personality = 0; |
| 262 | cieInfo->codeAlignFactor = 0; |
| 263 | cieInfo->dataAlignFactor = 0; |
| 264 | cieInfo->isSignalFrame = false; |
| 265 | cieInfo->fdesHaveAugmentationData = false; |
| 266 | cieInfo->cieStart = cie; |
| 267 | pint_t p = cie; |
| 268 | pint_t cieLength = (pint_t)addressSpace.get32(p); |
| 269 | p += 4; |
| 270 | pint_t cieContentEnd = p + cieLength; |
| 271 | if (cieLength == 0xffffffff) { |
| 272 | // 0xffffffff means length is really next 8 bytes |
| 273 | cieLength = (pint_t)addressSpace.get64(p); |
| 274 | p += 8; |
| 275 | cieContentEnd = p + cieLength; |
| 276 | } |
| 277 | if (cieLength == 0) |
| 278 | return NULL; |
| 279 | // CIE ID is always 0 |
| 280 | if (addressSpace.get32(p) != 0) |
| 281 | return "CIE ID is not zero"; |
| 282 | p += 4; |
| 283 | // Version is always 1 or 3 |
| 284 | uint8_t version = addressSpace.get8(p); |
| 285 | if ((version != 1) && (version != 3)) |
| 286 | return "CIE version is not 1 or 3"; |
| 287 | ++p; |
| 288 | // save start of augmentation string and find end |
| 289 | pint_t strStart = p; |
| 290 | while (addressSpace.get8(p) != 0) |
| 291 | ++p; |
| 292 | ++p; |
| 293 | // parse code aligment factor |
| 294 | cieInfo->codeAlignFactor = (uint32_t)addressSpace.getULEB128(p, cieContentEnd); |
| 295 | // parse data alignment factor |
| 296 | cieInfo->dataAlignFactor = (int)addressSpace.getSLEB128(p, cieContentEnd); |
| 297 | // parse return address register |
| 298 | uint64_t raReg = addressSpace.getULEB128(p, cieContentEnd); |
| 299 | assert(raReg < 255 && "return address register too large"); |
| 300 | cieInfo->returnAddressRegister = (uint8_t)raReg; |
| 301 | // parse augmentation data based on augmentation string |
| 302 | const char *result = NULL; |
| 303 | if (addressSpace.get8(strStart) == 'z') { |
| 304 | // parse augmentation data length |
| 305 | addressSpace.getULEB128(p, cieContentEnd); |
| 306 | for (pint_t s = strStart; addressSpace.get8(s) != '\0'; ++s) { |
| 307 | switch (addressSpace.get8(s)) { |
| 308 | case 'z': |
| 309 | cieInfo->fdesHaveAugmentationData = true; |
| 310 | break; |
| 311 | case 'P': |
| 312 | cieInfo->personalityEncoding = addressSpace.get8(p); |
| 313 | ++p; |
| 314 | cieInfo->personalityOffsetInCIE = (uint8_t)(p - cie); |
| 315 | cieInfo->personality = addressSpace |
| 316 | .getEncodedP(p, cieContentEnd, cieInfo->personalityEncoding); |
| 317 | break; |
| 318 | case 'L': |
| 319 | cieInfo->lsdaEncoding = addressSpace.get8(p); |
| 320 | ++p; |
| 321 | break; |
| 322 | case 'R': |
| 323 | cieInfo->pointerEncoding = addressSpace.get8(p); |
| 324 | ++p; |
| 325 | break; |
| 326 | case 'S': |
| 327 | cieInfo->isSignalFrame = true; |
| 328 | break; |
| 329 | default: |
| 330 | // ignore unknown letters |
| 331 | break; |
| 332 | } |
| 333 | } |
| 334 | } |
| 335 | cieInfo->cieLength = cieContentEnd - cieInfo->cieStart; |
| 336 | cieInfo->cieInstructions = p; |
| 337 | return result; |
| 338 | } |
| 339 | |
| 340 | |
Ed Maste | 63469ff | 2016-07-19 17:15:50 +0000 | [diff] [blame] | 341 | /// "run" the DWARF instructions and create the abstact PrologInfo for an FDE |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 342 | template <typename A> |
| 343 | bool CFI_Parser<A>::parseFDEInstructions(A &addressSpace, |
| 344 | const FDE_Info &fdeInfo, |
| 345 | const CIE_Info &cieInfo, pint_t upToPC, |
| 346 | PrologInfo *results) { |
| 347 | // clear results |
| 348 | memset(results, '\0', sizeof(PrologInfo)); |
| 349 | PrologInfoStackEntry *rememberStack = NULL; |
| 350 | |
| 351 | // parse CIE then FDE instructions |
| 352 | return parseInstructions(addressSpace, cieInfo.cieInstructions, |
| 353 | cieInfo.cieStart + cieInfo.cieLength, cieInfo, |
| 354 | (pint_t)(-1), rememberStack, results) && |
| 355 | parseInstructions(addressSpace, fdeInfo.fdeInstructions, |
| 356 | fdeInfo.fdeStart + fdeInfo.fdeLength, cieInfo, |
| 357 | upToPC - fdeInfo.pcStart, rememberStack, results); |
| 358 | } |
| 359 | |
Ed Maste | 63469ff | 2016-07-19 17:15:50 +0000 | [diff] [blame] | 360 | /// "run" the DWARF instructions |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 361 | template <typename A> |
| 362 | bool CFI_Parser<A>::parseInstructions(A &addressSpace, pint_t instructions, |
| 363 | pint_t instructionsEnd, |
| 364 | const CIE_Info &cieInfo, pint_t pcoffset, |
| 365 | PrologInfoStackEntry *&rememberStack, |
| 366 | PrologInfo *results) { |
| 367 | const bool logDwarf = false; |
| 368 | pint_t p = instructions; |
| 369 | pint_t codeOffset = 0; |
| 370 | PrologInfo initialState = *results; |
| 371 | if (logDwarf) |
| 372 | fprintf(stderr, "parseInstructions(instructions=0x%0" PRIx64 ")\n", |
| 373 | (uint64_t)instructionsEnd); |
| 374 | |
Ed Maste | 63469ff | 2016-07-19 17:15:50 +0000 | [diff] [blame] | 375 | // see DWARF Spec, section 6.4.2 for details on unwind opcodes |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 376 | while ((p < instructionsEnd) && (codeOffset < pcoffset)) { |
| 377 | uint64_t reg; |
| 378 | uint64_t reg2; |
| 379 | int64_t offset; |
| 380 | uint64_t length; |
| 381 | uint8_t opcode = addressSpace.get8(p); |
| 382 | uint8_t operand; |
Peter Zotov | 543f848 | 2015-11-09 06:57:29 +0000 | [diff] [blame] | 383 | #if !defined(_LIBUNWIND_NO_HEAP) |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 384 | PrologInfoStackEntry *entry; |
Peter Zotov | 543f848 | 2015-11-09 06:57:29 +0000 | [diff] [blame] | 385 | #endif |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 386 | ++p; |
| 387 | switch (opcode) { |
| 388 | case DW_CFA_nop: |
| 389 | if (logDwarf) |
| 390 | fprintf(stderr, "DW_CFA_nop\n"); |
| 391 | break; |
| 392 | case DW_CFA_set_loc: |
| 393 | codeOffset = |
| 394 | addressSpace.getEncodedP(p, instructionsEnd, cieInfo.pointerEncoding); |
| 395 | if (logDwarf) |
| 396 | fprintf(stderr, "DW_CFA_set_loc\n"); |
| 397 | break; |
| 398 | case DW_CFA_advance_loc1: |
| 399 | codeOffset += (addressSpace.get8(p) * cieInfo.codeAlignFactor); |
| 400 | p += 1; |
| 401 | if (logDwarf) |
| 402 | fprintf(stderr, "DW_CFA_advance_loc1: new offset=%" PRIu64 "\n", |
| 403 | (uint64_t)codeOffset); |
| 404 | break; |
| 405 | case DW_CFA_advance_loc2: |
| 406 | codeOffset += (addressSpace.get16(p) * cieInfo.codeAlignFactor); |
| 407 | p += 2; |
| 408 | if (logDwarf) |
| 409 | fprintf(stderr, "DW_CFA_advance_loc2: new offset=%" PRIu64 "\n", |
| 410 | (uint64_t)codeOffset); |
| 411 | break; |
| 412 | case DW_CFA_advance_loc4: |
| 413 | codeOffset += (addressSpace.get32(p) * cieInfo.codeAlignFactor); |
| 414 | p += 4; |
| 415 | if (logDwarf) |
| 416 | fprintf(stderr, "DW_CFA_advance_loc4: new offset=%" PRIu64 "\n", |
| 417 | (uint64_t)codeOffset); |
| 418 | break; |
| 419 | case DW_CFA_offset_extended: |
| 420 | reg = addressSpace.getULEB128(p, instructionsEnd); |
| 421 | offset = (int64_t)addressSpace.getULEB128(p, instructionsEnd) |
| 422 | * cieInfo.dataAlignFactor; |
| 423 | if (reg > kMaxRegisterNumber) { |
| 424 | fprintf(stderr, |
Ed Maste | 63469ff | 2016-07-19 17:15:50 +0000 | [diff] [blame] | 425 | "malformed DW_CFA_offset_extended DWARF unwind, reg too big\n"); |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 426 | return false; |
| 427 | } |
| 428 | results->savedRegisters[reg].location = kRegisterInCFA; |
| 429 | results->savedRegisters[reg].value = offset; |
| 430 | if (logDwarf) |
| 431 | fprintf(stderr, |
| 432 | "DW_CFA_offset_extended(reg=%" PRIu64 ", offset=%" PRId64 ")\n", |
| 433 | reg, offset); |
| 434 | break; |
| 435 | case DW_CFA_restore_extended: |
| 436 | reg = addressSpace.getULEB128(p, instructionsEnd); |
| 437 | ; |
| 438 | if (reg > kMaxRegisterNumber) { |
| 439 | fprintf( |
| 440 | stderr, |
Ed Maste | 63469ff | 2016-07-19 17:15:50 +0000 | [diff] [blame] | 441 | "malformed DW_CFA_restore_extended DWARF unwind, reg too big\n"); |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 442 | return false; |
| 443 | } |
| 444 | results->savedRegisters[reg] = initialState.savedRegisters[reg]; |
| 445 | if (logDwarf) |
| 446 | fprintf(stderr, "DW_CFA_restore_extended(reg=%" PRIu64 ")\n", reg); |
| 447 | break; |
| 448 | case DW_CFA_undefined: |
| 449 | reg = addressSpace.getULEB128(p, instructionsEnd); |
| 450 | if (reg > kMaxRegisterNumber) { |
| 451 | fprintf(stderr, |
Ed Maste | 63469ff | 2016-07-19 17:15:50 +0000 | [diff] [blame] | 452 | "malformed DW_CFA_undefined DWARF unwind, reg too big\n"); |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 453 | return false; |
| 454 | } |
| 455 | results->savedRegisters[reg].location = kRegisterUnused; |
| 456 | if (logDwarf) |
| 457 | fprintf(stderr, "DW_CFA_undefined(reg=%" PRIu64 ")\n", reg); |
| 458 | break; |
| 459 | case DW_CFA_same_value: |
| 460 | reg = addressSpace.getULEB128(p, instructionsEnd); |
| 461 | if (reg > kMaxRegisterNumber) { |
| 462 | fprintf(stderr, |
Ed Maste | 63469ff | 2016-07-19 17:15:50 +0000 | [diff] [blame] | 463 | "malformed DW_CFA_same_value DWARF unwind, reg too big\n"); |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 464 | return false; |
| 465 | } |
| 466 | // <rdar://problem/8456377> DW_CFA_same_value unsupported |
| 467 | // "same value" means register was stored in frame, but its current |
| 468 | // value has not changed, so no need to restore from frame. |
| 469 | // We model this as if the register was never saved. |
| 470 | results->savedRegisters[reg].location = kRegisterUnused; |
| 471 | // set flag to disable conversion to compact unwind |
| 472 | results->sameValueUsed = true; |
| 473 | if (logDwarf) |
| 474 | fprintf(stderr, "DW_CFA_same_value(reg=%" PRIu64 ")\n", reg); |
| 475 | break; |
| 476 | case DW_CFA_register: |
| 477 | reg = addressSpace.getULEB128(p, instructionsEnd); |
| 478 | reg2 = addressSpace.getULEB128(p, instructionsEnd); |
| 479 | if (reg > kMaxRegisterNumber) { |
| 480 | fprintf(stderr, |
Ed Maste | 63469ff | 2016-07-19 17:15:50 +0000 | [diff] [blame] | 481 | "malformed DW_CFA_register DWARF unwind, reg too big\n"); |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 482 | return false; |
| 483 | } |
| 484 | if (reg2 > kMaxRegisterNumber) { |
| 485 | fprintf(stderr, |
Ed Maste | 63469ff | 2016-07-19 17:15:50 +0000 | [diff] [blame] | 486 | "malformed DW_CFA_register DWARF unwind, reg2 too big\n"); |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 487 | return false; |
| 488 | } |
| 489 | results->savedRegisters[reg].location = kRegisterInRegister; |
| 490 | results->savedRegisters[reg].value = (int64_t)reg2; |
| 491 | // set flag to disable conversion to compact unwind |
| 492 | results->registersInOtherRegisters = true; |
| 493 | if (logDwarf) |
| 494 | fprintf(stderr, "DW_CFA_register(reg=%" PRIu64 ", reg2=%" PRIu64 ")\n", |
| 495 | reg, reg2); |
| 496 | break; |
Peter Zotov | 543f848 | 2015-11-09 06:57:29 +0000 | [diff] [blame] | 497 | #if !defined(_LIBUNWIND_NO_HEAP) |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 498 | case DW_CFA_remember_state: |
| 499 | // avoid operator new, because that would be an upward dependency |
| 500 | entry = (PrologInfoStackEntry *)malloc(sizeof(PrologInfoStackEntry)); |
| 501 | if (entry != NULL) { |
| 502 | entry->next = rememberStack; |
| 503 | entry->info = *results; |
| 504 | rememberStack = entry; |
| 505 | } else { |
| 506 | return false; |
| 507 | } |
| 508 | if (logDwarf) |
| 509 | fprintf(stderr, "DW_CFA_remember_state\n"); |
| 510 | break; |
| 511 | case DW_CFA_restore_state: |
| 512 | if (rememberStack != NULL) { |
| 513 | PrologInfoStackEntry *top = rememberStack; |
| 514 | *results = top->info; |
| 515 | rememberStack = top->next; |
| 516 | free((char *)top); |
| 517 | } else { |
| 518 | return false; |
| 519 | } |
| 520 | if (logDwarf) |
| 521 | fprintf(stderr, "DW_CFA_restore_state\n"); |
| 522 | break; |
Peter Zotov | 543f848 | 2015-11-09 06:57:29 +0000 | [diff] [blame] | 523 | #endif |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 524 | case DW_CFA_def_cfa: |
| 525 | reg = addressSpace.getULEB128(p, instructionsEnd); |
| 526 | offset = (int64_t)addressSpace.getULEB128(p, instructionsEnd); |
| 527 | if (reg > kMaxRegisterNumber) { |
Ed Maste | 63469ff | 2016-07-19 17:15:50 +0000 | [diff] [blame] | 528 | fprintf(stderr, "malformed DW_CFA_def_cfa DWARF unwind, reg too big\n"); |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 529 | return false; |
| 530 | } |
| 531 | results->cfaRegister = (uint32_t)reg; |
| 532 | results->cfaRegisterOffset = (int32_t)offset; |
| 533 | if (logDwarf) |
| 534 | fprintf(stderr, "DW_CFA_def_cfa(reg=%" PRIu64 ", offset=%" PRIu64 ")\n", |
| 535 | reg, offset); |
| 536 | break; |
| 537 | case DW_CFA_def_cfa_register: |
| 538 | reg = addressSpace.getULEB128(p, instructionsEnd); |
| 539 | if (reg > kMaxRegisterNumber) { |
| 540 | fprintf( |
| 541 | stderr, |
Ed Maste | 63469ff | 2016-07-19 17:15:50 +0000 | [diff] [blame] | 542 | "malformed DW_CFA_def_cfa_register DWARF unwind, reg too big\n"); |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 543 | return false; |
| 544 | } |
| 545 | results->cfaRegister = (uint32_t)reg; |
| 546 | if (logDwarf) |
| 547 | fprintf(stderr, "DW_CFA_def_cfa_register(%" PRIu64 ")\n", reg); |
| 548 | break; |
| 549 | case DW_CFA_def_cfa_offset: |
| 550 | results->cfaRegisterOffset = (int32_t) |
| 551 | addressSpace.getULEB128(p, instructionsEnd); |
| 552 | results->codeOffsetAtStackDecrement = (uint32_t)codeOffset; |
| 553 | if (logDwarf) |
| 554 | fprintf(stderr, "DW_CFA_def_cfa_offset(%d)\n", |
| 555 | results->cfaRegisterOffset); |
| 556 | break; |
| 557 | case DW_CFA_def_cfa_expression: |
| 558 | results->cfaRegister = 0; |
| 559 | results->cfaExpression = (int64_t)p; |
| 560 | length = addressSpace.getULEB128(p, instructionsEnd); |
| 561 | p += length; |
| 562 | if (logDwarf) |
| 563 | fprintf(stderr, "DW_CFA_def_cfa_expression(expression=0x%" PRIx64 |
| 564 | ", length=%" PRIu64 ")\n", |
| 565 | results->cfaExpression, length); |
| 566 | break; |
| 567 | case DW_CFA_expression: |
| 568 | reg = addressSpace.getULEB128(p, instructionsEnd); |
| 569 | if (reg > kMaxRegisterNumber) { |
| 570 | fprintf(stderr, |
Ed Maste | 63469ff | 2016-07-19 17:15:50 +0000 | [diff] [blame] | 571 | "malformed DW_CFA_expression DWARF unwind, reg too big\n"); |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 572 | return false; |
| 573 | } |
| 574 | results->savedRegisters[reg].location = kRegisterAtExpression; |
| 575 | results->savedRegisters[reg].value = (int64_t)p; |
| 576 | length = addressSpace.getULEB128(p, instructionsEnd); |
| 577 | p += length; |
| 578 | if (logDwarf) |
| 579 | fprintf(stderr, "DW_CFA_expression(reg=%" PRIu64 |
| 580 | ", expression=0x%" PRIx64 ", length=%" PRIu64 ")\n", |
| 581 | reg, results->savedRegisters[reg].value, length); |
| 582 | break; |
| 583 | case DW_CFA_offset_extended_sf: |
| 584 | reg = addressSpace.getULEB128(p, instructionsEnd); |
| 585 | if (reg > kMaxRegisterNumber) { |
| 586 | fprintf( |
| 587 | stderr, |
Ed Maste | 63469ff | 2016-07-19 17:15:50 +0000 | [diff] [blame] | 588 | "malformed DW_CFA_offset_extended_sf DWARF unwind, reg too big\n"); |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 589 | return false; |
| 590 | } |
| 591 | offset = |
| 592 | addressSpace.getSLEB128(p, instructionsEnd) * cieInfo.dataAlignFactor; |
| 593 | results->savedRegisters[reg].location = kRegisterInCFA; |
| 594 | results->savedRegisters[reg].value = offset; |
| 595 | if (logDwarf) |
| 596 | fprintf(stderr, "DW_CFA_offset_extended_sf(reg=%" PRIu64 |
| 597 | ", offset=%" PRId64 ")\n", |
| 598 | reg, offset); |
| 599 | break; |
| 600 | case DW_CFA_def_cfa_sf: |
| 601 | reg = addressSpace.getULEB128(p, instructionsEnd); |
| 602 | offset = |
| 603 | addressSpace.getSLEB128(p, instructionsEnd) * cieInfo.dataAlignFactor; |
| 604 | if (reg > kMaxRegisterNumber) { |
| 605 | fprintf(stderr, |
Ed Maste | 63469ff | 2016-07-19 17:15:50 +0000 | [diff] [blame] | 606 | "malformed DW_CFA_def_cfa_sf DWARF unwind, reg too big\n"); |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 607 | return false; |
| 608 | } |
| 609 | results->cfaRegister = (uint32_t)reg; |
| 610 | results->cfaRegisterOffset = (int32_t)offset; |
| 611 | if (logDwarf) |
| 612 | fprintf(stderr, |
| 613 | "DW_CFA_def_cfa_sf(reg=%" PRIu64 ", offset=%" PRId64 ")\n", reg, |
| 614 | offset); |
| 615 | break; |
| 616 | case DW_CFA_def_cfa_offset_sf: |
| 617 | results->cfaRegisterOffset = (int32_t) |
| 618 | (addressSpace.getSLEB128(p, instructionsEnd) * cieInfo.dataAlignFactor); |
| 619 | results->codeOffsetAtStackDecrement = (uint32_t)codeOffset; |
| 620 | if (logDwarf) |
| 621 | fprintf(stderr, "DW_CFA_def_cfa_offset_sf(%d)\n", |
| 622 | results->cfaRegisterOffset); |
| 623 | break; |
| 624 | case DW_CFA_val_offset: |
| 625 | reg = addressSpace.getULEB128(p, instructionsEnd); |
| 626 | offset = (int64_t)addressSpace.getULEB128(p, instructionsEnd) |
| 627 | * cieInfo.dataAlignFactor; |
| 628 | results->savedRegisters[reg].location = kRegisterOffsetFromCFA; |
| 629 | results->savedRegisters[reg].value = offset; |
| 630 | if (logDwarf) |
| 631 | fprintf(stderr, |
| 632 | "DW_CFA_val_offset(reg=%" PRIu64 ", offset=%" PRId64 "\n", reg, |
| 633 | offset); |
| 634 | break; |
| 635 | case DW_CFA_val_offset_sf: |
| 636 | reg = addressSpace.getULEB128(p, instructionsEnd); |
| 637 | if (reg > kMaxRegisterNumber) { |
| 638 | fprintf(stderr, |
Ed Maste | 63469ff | 2016-07-19 17:15:50 +0000 | [diff] [blame] | 639 | "malformed DW_CFA_val_offset_sf DWARF unwind, reg too big\n"); |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 640 | return false; |
| 641 | } |
| 642 | offset = |
| 643 | addressSpace.getSLEB128(p, instructionsEnd) * cieInfo.dataAlignFactor; |
| 644 | results->savedRegisters[reg].location = kRegisterOffsetFromCFA; |
| 645 | results->savedRegisters[reg].value = offset; |
| 646 | if (logDwarf) |
| 647 | fprintf(stderr, |
| 648 | "DW_CFA_val_offset_sf(reg=%" PRIu64 ", offset=%" PRId64 "\n", |
| 649 | reg, offset); |
| 650 | break; |
| 651 | case DW_CFA_val_expression: |
| 652 | reg = addressSpace.getULEB128(p, instructionsEnd); |
| 653 | if (reg > kMaxRegisterNumber) { |
| 654 | fprintf(stderr, |
Ed Maste | 63469ff | 2016-07-19 17:15:50 +0000 | [diff] [blame] | 655 | "malformed DW_CFA_val_expression DWARF unwind, reg too big\n"); |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 656 | return false; |
| 657 | } |
| 658 | results->savedRegisters[reg].location = kRegisterIsExpression; |
| 659 | results->savedRegisters[reg].value = (int64_t)p; |
| 660 | length = addressSpace.getULEB128(p, instructionsEnd); |
| 661 | p += length; |
| 662 | if (logDwarf) |
| 663 | fprintf(stderr, "DW_CFA_val_expression(reg=%" PRIu64 |
| 664 | ", expression=0x%" PRIx64 ", length=%" PRIu64 ")\n", |
| 665 | reg, results->savedRegisters[reg].value, length); |
| 666 | break; |
| 667 | case DW_CFA_GNU_args_size: |
| 668 | length = addressSpace.getULEB128(p, instructionsEnd); |
| 669 | results->spExtraArgSize = (uint32_t)length; |
| 670 | if (logDwarf) |
| 671 | fprintf(stderr, "DW_CFA_GNU_args_size(%" PRIu64 ")\n", length); |
| 672 | break; |
| 673 | case DW_CFA_GNU_negative_offset_extended: |
| 674 | reg = addressSpace.getULEB128(p, instructionsEnd); |
| 675 | if (reg > kMaxRegisterNumber) { |
Ed Maste | 63469ff | 2016-07-19 17:15:50 +0000 | [diff] [blame] | 676 | fprintf(stderr, "malformed DW_CFA_GNU_negative_offset_extended DWARF " |
Saleem Abdulrasool | 675df58 | 2015-04-24 19:39:17 +0000 | [diff] [blame] | 677 | "unwind, reg too big\n"); |
| 678 | return false; |
| 679 | } |
| 680 | offset = (int64_t)addressSpace.getULEB128(p, instructionsEnd) |
| 681 | * cieInfo.dataAlignFactor; |
| 682 | results->savedRegisters[reg].location = kRegisterInCFA; |
| 683 | results->savedRegisters[reg].value = -offset; |
| 684 | if (logDwarf) |
| 685 | fprintf(stderr, "DW_CFA_GNU_negative_offset_extended(%" PRId64 ")\n", |
| 686 | offset); |
| 687 | break; |
| 688 | default: |
| 689 | operand = opcode & 0x3F; |
| 690 | switch (opcode & 0xC0) { |
| 691 | case DW_CFA_offset: |
| 692 | reg = operand; |
| 693 | offset = (int64_t)addressSpace.getULEB128(p, instructionsEnd) |
| 694 | * cieInfo.dataAlignFactor; |
| 695 | results->savedRegisters[reg].location = kRegisterInCFA; |
| 696 | results->savedRegisters[reg].value = offset; |
| 697 | if (logDwarf) |
| 698 | fprintf(stderr, "DW_CFA_offset(reg=%d, offset=%" PRId64 ")\n", |
| 699 | operand, offset); |
| 700 | break; |
| 701 | case DW_CFA_advance_loc: |
| 702 | codeOffset += operand * cieInfo.codeAlignFactor; |
| 703 | if (logDwarf) |
| 704 | fprintf(stderr, "DW_CFA_advance_loc: new offset=%" PRIu64 "\n", |
| 705 | (uint64_t)codeOffset); |
| 706 | break; |
| 707 | case DW_CFA_restore: |
| 708 | reg = operand; |
| 709 | results->savedRegisters[reg] = initialState.savedRegisters[reg]; |
| 710 | if (logDwarf) |
| 711 | fprintf(stderr, "DW_CFA_restore(reg=%" PRIu64 ")\n", reg); |
| 712 | break; |
| 713 | default: |
| 714 | if (logDwarf) |
| 715 | fprintf(stderr, "unknown CFA opcode 0x%02X\n", opcode); |
| 716 | return false; |
| 717 | } |
| 718 | } |
| 719 | } |
| 720 | |
| 721 | return true; |
| 722 | } |
| 723 | |
| 724 | } // namespace libunwind |
| 725 | |
| 726 | #endif // __DWARF_PARSER_HPP__ |