1 //===----------------------------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 // 8 // C++ interface to lower levels of libunwind 9 //===----------------------------------------------------------------------===// 10 11 #ifndef __UNWINDCURSOR_HPP__ 12 #define __UNWINDCURSOR_HPP__ 13 14 #include "cet_unwind.h" 15 #include <stdint.h> 16 #include <stdio.h> 17 #include <stdlib.h> 18 #include <unwind.h> 19 20 #ifdef _WIN32 21 #include <windows.h> 22 #include <ntverp.h> 23 #endif 24 #ifdef __APPLE__ 25 #include <mach-o/dyld.h> 26 #endif 27 #ifdef _AIX 28 #include <dlfcn.h> 29 #include <sys/debug.h> 30 #include <sys/pseg.h> 31 #endif 32 33 #if defined(_LIBUNWIND_TARGET_LINUX) && \ 34 (defined(_LIBUNWIND_TARGET_AARCH64) || defined(_LIBUNWIND_TARGET_RISCV) || \ 35 defined(_LIBUNWIND_TARGET_S390X)) 36 #include <errno.h> 37 #include <signal.h> 38 #include <sys/syscall.h> 39 #include <unistd.h> 40 #define _LIBUNWIND_CHECK_LINUX_SIGRETURN 1 41 #endif 42 43 #include "AddressSpace.hpp" 44 #include "CompactUnwinder.hpp" 45 #include "config.h" 46 #include "DwarfInstructions.hpp" 47 #include "EHHeaderParser.hpp" 48 #include "libunwind.h" 49 #include "libunwind_ext.h" 50 #include "Registers.hpp" 51 #include "RWMutex.hpp" 52 #include "Unwind-EHABI.h" 53 54 #if defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) 55 // Provide a definition for the DISPATCHER_CONTEXT struct for old (Win7 and 56 // earlier) SDKs. 57 // MinGW-w64 has always provided this struct. 58 #if defined(_WIN32) && defined(_LIBUNWIND_TARGET_X86_64) && \ 59 !defined(__MINGW32__) && VER_PRODUCTBUILD < 8000 60 struct _DISPATCHER_CONTEXT { 61 ULONG64 ControlPc; 62 ULONG64 ImageBase; 63 PRUNTIME_FUNCTION FunctionEntry; 64 ULONG64 EstablisherFrame; 65 ULONG64 TargetIp; 66 PCONTEXT ContextRecord; 67 PEXCEPTION_ROUTINE LanguageHandler; 68 PVOID HandlerData; 69 PUNWIND_HISTORY_TABLE HistoryTable; 70 ULONG ScopeIndex; 71 ULONG Fill0; 72 }; 73 #endif 74 75 struct UNWIND_INFO { 76 uint8_t Version : 3; 77 uint8_t Flags : 5; 78 uint8_t SizeOfProlog; 79 uint8_t CountOfCodes; 80 uint8_t FrameRegister : 4; 81 uint8_t FrameOffset : 4; 82 uint16_t UnwindCodes[2]; 83 }; 84 85 extern "C" _Unwind_Reason_Code __libunwind_seh_personality( 86 int, _Unwind_Action, uint64_t, _Unwind_Exception *, 87 struct _Unwind_Context *); 88 89 #endif 90 91 namespace libunwind { 92 93 #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 94 /// Cache of recently found FDEs. 95 template <typename A> 96 class _LIBUNWIND_HIDDEN DwarfFDECache { 97 typedef typename A::pint_t pint_t; 98 public: 99 static constexpr pint_t kSearchAll = static_cast<pint_t>(-1); 100 static pint_t findFDE(pint_t mh, pint_t pc); 101 static void add(pint_t mh, pint_t ip_start, pint_t ip_end, pint_t fde); 102 static void removeAllIn(pint_t mh); 103 static void iterateCacheEntries(void (*func)(unw_word_t ip_start, 104 unw_word_t ip_end, 105 unw_word_t fde, unw_word_t mh)); 106 107 private: 108 109 struct entry { 110 pint_t mh; 111 pint_t ip_start; 112 pint_t ip_end; 113 pint_t fde; 114 }; 115 116 // These fields are all static to avoid needing an initializer. 117 // There is only one instance of this class per process. 118 static RWMutex _lock; 119 #ifdef __APPLE__ 120 static void dyldUnloadHook(const struct mach_header *mh, intptr_t slide); 121 static bool _registeredForDyldUnloads; 122 #endif 123 static entry *_buffer; 124 static entry *_bufferUsed; 125 static entry *_bufferEnd; 126 static entry _initialBuffer[64]; 127 }; 128 129 template <typename A> 130 typename DwarfFDECache<A>::entry * 131 DwarfFDECache<A>::_buffer = _initialBuffer; 132 133 template <typename A> 134 typename DwarfFDECache<A>::entry * 135 DwarfFDECache<A>::_bufferUsed = _initialBuffer; 136 137 template <typename A> 138 typename DwarfFDECache<A>::entry * 139 DwarfFDECache<A>::_bufferEnd = &_initialBuffer[64]; 140 141 template <typename A> 142 typename DwarfFDECache<A>::entry DwarfFDECache<A>::_initialBuffer[64]; 143 144 template <typename A> 145 RWMutex DwarfFDECache<A>::_lock; 146 147 #ifdef __APPLE__ 148 template <typename A> 149 bool DwarfFDECache<A>::_registeredForDyldUnloads = false; 150 #endif 151 152 template <typename A> 153 typename A::pint_t DwarfFDECache<A>::findFDE(pint_t mh, pint_t pc) { 154 pint_t result = 0; 155 _LIBUNWIND_LOG_IF_FALSE(_lock.lock_shared()); 156 for (entry *p = _buffer; p < _bufferUsed; ++p) { 157 if ((mh == p->mh) || (mh == kSearchAll)) { 158 if ((p->ip_start <= pc) && (pc < p->ip_end)) { 159 result = p->fde; 160 break; 161 } 162 } 163 } 164 _LIBUNWIND_LOG_IF_FALSE(_lock.unlock_shared()); 165 return result; 166 } 167 168 template <typename A> 169 void DwarfFDECache<A>::add(pint_t mh, pint_t ip_start, pint_t ip_end, 170 pint_t fde) { 171 #if !defined(_LIBUNWIND_NO_HEAP) 172 _LIBUNWIND_LOG_IF_FALSE(_lock.lock()); 173 if (_bufferUsed >= _bufferEnd) { 174 size_t oldSize = (size_t)(_bufferEnd - _buffer); 175 size_t newSize = oldSize * 4; 176 // Can't use operator new (we are below it). 177 entry *newBuffer = (entry *)malloc(newSize * sizeof(entry)); 178 memcpy(newBuffer, _buffer, oldSize * sizeof(entry)); 179 if (_buffer != _initialBuffer) 180 free(_buffer); 181 _buffer = newBuffer; 182 _bufferUsed = &newBuffer[oldSize]; 183 _bufferEnd = &newBuffer[newSize]; 184 } 185 _bufferUsed->mh = mh; 186 _bufferUsed->ip_start = ip_start; 187 _bufferUsed->ip_end = ip_end; 188 _bufferUsed->fde = fde; 189 ++_bufferUsed; 190 #ifdef __APPLE__ 191 if (!_registeredForDyldUnloads) { 192 _dyld_register_func_for_remove_image(&dyldUnloadHook); 193 _registeredForDyldUnloads = true; 194 } 195 #endif 196 _LIBUNWIND_LOG_IF_FALSE(_lock.unlock()); 197 #endif 198 } 199 200 template <typename A> 201 void DwarfFDECache<A>::removeAllIn(pint_t mh) { 202 _LIBUNWIND_LOG_IF_FALSE(_lock.lock()); 203 entry *d = _buffer; 204 for (const entry *s = _buffer; s < _bufferUsed; ++s) { 205 if (s->mh != mh) { 206 if (d != s) 207 *d = *s; 208 ++d; 209 } 210 } 211 _bufferUsed = d; 212 _LIBUNWIND_LOG_IF_FALSE(_lock.unlock()); 213 } 214 215 #ifdef __APPLE__ 216 template <typename A> 217 void DwarfFDECache<A>::dyldUnloadHook(const struct mach_header *mh, intptr_t ) { 218 removeAllIn((pint_t) mh); 219 } 220 #endif 221 222 template <typename A> 223 void DwarfFDECache<A>::iterateCacheEntries(void (*func)( 224 unw_word_t ip_start, unw_word_t ip_end, unw_word_t fde, unw_word_t mh)) { 225 _LIBUNWIND_LOG_IF_FALSE(_lock.lock()); 226 for (entry *p = _buffer; p < _bufferUsed; ++p) { 227 (*func)(p->ip_start, p->ip_end, p->fde, p->mh); 228 } 229 _LIBUNWIND_LOG_IF_FALSE(_lock.unlock()); 230 } 231 #endif // defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 232 233 234 #define arrayoffsetof(type, index, field) ((size_t)(&((type *)0)[index].field)) 235 236 #if defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND) 237 template <typename A> class UnwindSectionHeader { 238 public: 239 UnwindSectionHeader(A &addressSpace, typename A::pint_t addr) 240 : _addressSpace(addressSpace), _addr(addr) {} 241 242 uint32_t version() const { 243 return _addressSpace.get32(_addr + 244 offsetof(unwind_info_section_header, version)); 245 } 246 uint32_t commonEncodingsArraySectionOffset() const { 247 return _addressSpace.get32(_addr + 248 offsetof(unwind_info_section_header, 249 commonEncodingsArraySectionOffset)); 250 } 251 uint32_t commonEncodingsArrayCount() const { 252 return _addressSpace.get32(_addr + offsetof(unwind_info_section_header, 253 commonEncodingsArrayCount)); 254 } 255 uint32_t personalityArraySectionOffset() const { 256 return _addressSpace.get32(_addr + offsetof(unwind_info_section_header, 257 personalityArraySectionOffset)); 258 } 259 uint32_t personalityArrayCount() const { 260 return _addressSpace.get32( 261 _addr + offsetof(unwind_info_section_header, personalityArrayCount)); 262 } 263 uint32_t indexSectionOffset() const { 264 return _addressSpace.get32( 265 _addr + offsetof(unwind_info_section_header, indexSectionOffset)); 266 } 267 uint32_t indexCount() const { 268 return _addressSpace.get32( 269 _addr + offsetof(unwind_info_section_header, indexCount)); 270 } 271 272 private: 273 A &_addressSpace; 274 typename A::pint_t _addr; 275 }; 276 277 template <typename A> class UnwindSectionIndexArray { 278 public: 279 UnwindSectionIndexArray(A &addressSpace, typename A::pint_t addr) 280 : _addressSpace(addressSpace), _addr(addr) {} 281 282 uint32_t functionOffset(uint32_t index) const { 283 return _addressSpace.get32( 284 _addr + arrayoffsetof(unwind_info_section_header_index_entry, index, 285 functionOffset)); 286 } 287 uint32_t secondLevelPagesSectionOffset(uint32_t index) const { 288 return _addressSpace.get32( 289 _addr + arrayoffsetof(unwind_info_section_header_index_entry, index, 290 secondLevelPagesSectionOffset)); 291 } 292 uint32_t lsdaIndexArraySectionOffset(uint32_t index) const { 293 return _addressSpace.get32( 294 _addr + arrayoffsetof(unwind_info_section_header_index_entry, index, 295 lsdaIndexArraySectionOffset)); 296 } 297 298 private: 299 A &_addressSpace; 300 typename A::pint_t _addr; 301 }; 302 303 template <typename A> class UnwindSectionRegularPageHeader { 304 public: 305 UnwindSectionRegularPageHeader(A &addressSpace, typename A::pint_t addr) 306 : _addressSpace(addressSpace), _addr(addr) {} 307 308 uint32_t kind() const { 309 return _addressSpace.get32( 310 _addr + offsetof(unwind_info_regular_second_level_page_header, kind)); 311 } 312 uint16_t entryPageOffset() const { 313 return _addressSpace.get16( 314 _addr + offsetof(unwind_info_regular_second_level_page_header, 315 entryPageOffset)); 316 } 317 uint16_t entryCount() const { 318 return _addressSpace.get16( 319 _addr + 320 offsetof(unwind_info_regular_second_level_page_header, entryCount)); 321 } 322 323 private: 324 A &_addressSpace; 325 typename A::pint_t _addr; 326 }; 327 328 template <typename A> class UnwindSectionRegularArray { 329 public: 330 UnwindSectionRegularArray(A &addressSpace, typename A::pint_t addr) 331 : _addressSpace(addressSpace), _addr(addr) {} 332 333 uint32_t functionOffset(uint32_t index) const { 334 return _addressSpace.get32( 335 _addr + arrayoffsetof(unwind_info_regular_second_level_entry, index, 336 functionOffset)); 337 } 338 uint32_t encoding(uint32_t index) const { 339 return _addressSpace.get32( 340 _addr + 341 arrayoffsetof(unwind_info_regular_second_level_entry, index, encoding)); 342 } 343 344 private: 345 A &_addressSpace; 346 typename A::pint_t _addr; 347 }; 348 349 template <typename A> class UnwindSectionCompressedPageHeader { 350 public: 351 UnwindSectionCompressedPageHeader(A &addressSpace, typename A::pint_t addr) 352 : _addressSpace(addressSpace), _addr(addr) {} 353 354 uint32_t kind() const { 355 return _addressSpace.get32( 356 _addr + 357 offsetof(unwind_info_compressed_second_level_page_header, kind)); 358 } 359 uint16_t entryPageOffset() const { 360 return _addressSpace.get16( 361 _addr + offsetof(unwind_info_compressed_second_level_page_header, 362 entryPageOffset)); 363 } 364 uint16_t entryCount() const { 365 return _addressSpace.get16( 366 _addr + 367 offsetof(unwind_info_compressed_second_level_page_header, entryCount)); 368 } 369 uint16_t encodingsPageOffset() const { 370 return _addressSpace.get16( 371 _addr + offsetof(unwind_info_compressed_second_level_page_header, 372 encodingsPageOffset)); 373 } 374 uint16_t encodingsCount() const { 375 return _addressSpace.get16( 376 _addr + offsetof(unwind_info_compressed_second_level_page_header, 377 encodingsCount)); 378 } 379 380 private: 381 A &_addressSpace; 382 typename A::pint_t _addr; 383 }; 384 385 template <typename A> class UnwindSectionCompressedArray { 386 public: 387 UnwindSectionCompressedArray(A &addressSpace, typename A::pint_t addr) 388 : _addressSpace(addressSpace), _addr(addr) {} 389 390 uint32_t functionOffset(uint32_t index) const { 391 return UNWIND_INFO_COMPRESSED_ENTRY_FUNC_OFFSET( 392 _addressSpace.get32(_addr + index * sizeof(uint32_t))); 393 } 394 uint16_t encodingIndex(uint32_t index) const { 395 return UNWIND_INFO_COMPRESSED_ENTRY_ENCODING_INDEX( 396 _addressSpace.get32(_addr + index * sizeof(uint32_t))); 397 } 398 399 private: 400 A &_addressSpace; 401 typename A::pint_t _addr; 402 }; 403 404 template <typename A> class UnwindSectionLsdaArray { 405 public: 406 UnwindSectionLsdaArray(A &addressSpace, typename A::pint_t addr) 407 : _addressSpace(addressSpace), _addr(addr) {} 408 409 uint32_t functionOffset(uint32_t index) const { 410 return _addressSpace.get32( 411 _addr + arrayoffsetof(unwind_info_section_header_lsda_index_entry, 412 index, functionOffset)); 413 } 414 uint32_t lsdaOffset(uint32_t index) const { 415 return _addressSpace.get32( 416 _addr + arrayoffsetof(unwind_info_section_header_lsda_index_entry, 417 index, lsdaOffset)); 418 } 419 420 private: 421 A &_addressSpace; 422 typename A::pint_t _addr; 423 }; 424 #endif // defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND) 425 426 class _LIBUNWIND_HIDDEN AbstractUnwindCursor { 427 public: 428 // NOTE: provide a class specific placement deallocation function (S5.3.4 p20) 429 // This avoids an unnecessary dependency to libc++abi. 430 void operator delete(void *, size_t) {} 431 432 virtual ~AbstractUnwindCursor() {} 433 virtual bool validReg(int) { _LIBUNWIND_ABORT("validReg not implemented"); } 434 virtual unw_word_t getReg(int) { _LIBUNWIND_ABORT("getReg not implemented"); } 435 virtual void setReg(int, unw_word_t) { 436 _LIBUNWIND_ABORT("setReg not implemented"); 437 } 438 virtual bool validFloatReg(int) { 439 _LIBUNWIND_ABORT("validFloatReg not implemented"); 440 } 441 virtual unw_fpreg_t getFloatReg(int) { 442 _LIBUNWIND_ABORT("getFloatReg not implemented"); 443 } 444 virtual void setFloatReg(int, unw_fpreg_t) { 445 _LIBUNWIND_ABORT("setFloatReg not implemented"); 446 } 447 virtual int step(bool = false) { _LIBUNWIND_ABORT("step not implemented"); } 448 virtual void getInfo(unw_proc_info_t *) { 449 _LIBUNWIND_ABORT("getInfo not implemented"); 450 } 451 virtual void jumpto() { _LIBUNWIND_ABORT("jumpto not implemented"); } 452 virtual bool isSignalFrame() { 453 _LIBUNWIND_ABORT("isSignalFrame not implemented"); 454 } 455 virtual bool getFunctionName(char *, size_t, unw_word_t *) { 456 _LIBUNWIND_ABORT("getFunctionName not implemented"); 457 } 458 virtual void setInfoBasedOnIPRegister(bool = false) { 459 _LIBUNWIND_ABORT("setInfoBasedOnIPRegister not implemented"); 460 } 461 virtual const char *getRegisterName(int) { 462 _LIBUNWIND_ABORT("getRegisterName not implemented"); 463 } 464 #ifdef __arm__ 465 virtual void saveVFPAsX() { _LIBUNWIND_ABORT("saveVFPAsX not implemented"); } 466 #endif 467 468 #ifdef _AIX 469 virtual uintptr_t getDataRelBase() { 470 _LIBUNWIND_ABORT("getDataRelBase not implemented"); 471 } 472 #endif 473 474 #if defined(_LIBUNWIND_USE_CET) 475 virtual void *get_registers() { 476 _LIBUNWIND_ABORT("get_registers not implemented"); 477 } 478 #endif 479 }; 480 481 #if defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) && defined(_WIN32) 482 483 /// \c UnwindCursor contains all state (including all register values) during 484 /// an unwind. This is normally stack-allocated inside a unw_cursor_t. 485 template <typename A, typename R> 486 class UnwindCursor : public AbstractUnwindCursor { 487 typedef typename A::pint_t pint_t; 488 public: 489 UnwindCursor(unw_context_t *context, A &as); 490 UnwindCursor(CONTEXT *context, A &as); 491 UnwindCursor(A &as, void *threadArg); 492 virtual ~UnwindCursor() {} 493 virtual bool validReg(int); 494 virtual unw_word_t getReg(int); 495 virtual void setReg(int, unw_word_t); 496 virtual bool validFloatReg(int); 497 virtual unw_fpreg_t getFloatReg(int); 498 virtual void setFloatReg(int, unw_fpreg_t); 499 virtual int step(bool = false); 500 virtual void getInfo(unw_proc_info_t *); 501 virtual void jumpto(); 502 virtual bool isSignalFrame(); 503 virtual bool getFunctionName(char *buf, size_t len, unw_word_t *off); 504 virtual void setInfoBasedOnIPRegister(bool isReturnAddress = false); 505 virtual const char *getRegisterName(int num); 506 #ifdef __arm__ 507 virtual void saveVFPAsX(); 508 #endif 509 510 DISPATCHER_CONTEXT *getDispatcherContext() { return &_dispContext; } 511 void setDispatcherContext(DISPATCHER_CONTEXT *disp) { 512 _dispContext = *disp; 513 _info.lsda = reinterpret_cast<unw_word_t>(_dispContext.HandlerData); 514 if (_dispContext.LanguageHandler) { 515 _info.handler = reinterpret_cast<unw_word_t>(__libunwind_seh_personality); 516 } else 517 _info.handler = 0; 518 } 519 520 // libunwind does not and should not depend on C++ library which means that we 521 // need our own definition of inline placement new. 522 static void *operator new(size_t, UnwindCursor<A, R> *p) { return p; } 523 524 private: 525 526 pint_t getLastPC() const { return _dispContext.ControlPc; } 527 void setLastPC(pint_t pc) { _dispContext.ControlPc = pc; } 528 RUNTIME_FUNCTION *lookUpSEHUnwindInfo(pint_t pc, pint_t *base) { 529 #ifdef __arm__ 530 // Remove the thumb bit; FunctionEntry ranges don't include the thumb bit. 531 pc &= ~1U; 532 #endif 533 // If pc points exactly at the end of the range, we might resolve the 534 // next function instead. Decrement pc by 1 to fit inside the current 535 // function. 536 pc -= 1; 537 _dispContext.FunctionEntry = RtlLookupFunctionEntry(pc, 538 &_dispContext.ImageBase, 539 _dispContext.HistoryTable); 540 *base = _dispContext.ImageBase; 541 return _dispContext.FunctionEntry; 542 } 543 bool getInfoFromSEH(pint_t pc); 544 int stepWithSEHData() { 545 _dispContext.LanguageHandler = RtlVirtualUnwind(UNW_FLAG_UHANDLER, 546 _dispContext.ImageBase, 547 _dispContext.ControlPc, 548 _dispContext.FunctionEntry, 549 _dispContext.ContextRecord, 550 &_dispContext.HandlerData, 551 &_dispContext.EstablisherFrame, 552 NULL); 553 // Update some fields of the unwind info now, since we have them. 554 _info.lsda = reinterpret_cast<unw_word_t>(_dispContext.HandlerData); 555 if (_dispContext.LanguageHandler) { 556 _info.handler = reinterpret_cast<unw_word_t>(__libunwind_seh_personality); 557 } else 558 _info.handler = 0; 559 return UNW_STEP_SUCCESS; 560 } 561 562 A &_addressSpace; 563 unw_proc_info_t _info; 564 DISPATCHER_CONTEXT _dispContext; 565 CONTEXT _msContext; 566 UNWIND_HISTORY_TABLE _histTable; 567 bool _unwindInfoMissing; 568 }; 569 570 571 template <typename A, typename R> 572 UnwindCursor<A, R>::UnwindCursor(unw_context_t *context, A &as) 573 : _addressSpace(as), _unwindInfoMissing(false) { 574 static_assert((check_fit<UnwindCursor<A, R>, unw_cursor_t>::does_fit), 575 "UnwindCursor<> does not fit in unw_cursor_t"); 576 static_assert((alignof(UnwindCursor<A, R>) <= alignof(unw_cursor_t)), 577 "UnwindCursor<> requires more alignment than unw_cursor_t"); 578 memset(&_info, 0, sizeof(_info)); 579 memset(&_histTable, 0, sizeof(_histTable)); 580 memset(&_dispContext, 0, sizeof(_dispContext)); 581 _dispContext.ContextRecord = &_msContext; 582 _dispContext.HistoryTable = &_histTable; 583 // Initialize MS context from ours. 584 R r(context); 585 RtlCaptureContext(&_msContext); 586 _msContext.ContextFlags = CONTEXT_CONTROL|CONTEXT_INTEGER|CONTEXT_FLOATING_POINT; 587 #if defined(_LIBUNWIND_TARGET_X86_64) 588 _msContext.Rax = r.getRegister(UNW_X86_64_RAX); 589 _msContext.Rcx = r.getRegister(UNW_X86_64_RCX); 590 _msContext.Rdx = r.getRegister(UNW_X86_64_RDX); 591 _msContext.Rbx = r.getRegister(UNW_X86_64_RBX); 592 _msContext.Rsp = r.getRegister(UNW_X86_64_RSP); 593 _msContext.Rbp = r.getRegister(UNW_X86_64_RBP); 594 _msContext.Rsi = r.getRegister(UNW_X86_64_RSI); 595 _msContext.Rdi = r.getRegister(UNW_X86_64_RDI); 596 _msContext.R8 = r.getRegister(UNW_X86_64_R8); 597 _msContext.R9 = r.getRegister(UNW_X86_64_R9); 598 _msContext.R10 = r.getRegister(UNW_X86_64_R10); 599 _msContext.R11 = r.getRegister(UNW_X86_64_R11); 600 _msContext.R12 = r.getRegister(UNW_X86_64_R12); 601 _msContext.R13 = r.getRegister(UNW_X86_64_R13); 602 _msContext.R14 = r.getRegister(UNW_X86_64_R14); 603 _msContext.R15 = r.getRegister(UNW_X86_64_R15); 604 _msContext.Rip = r.getRegister(UNW_REG_IP); 605 union { 606 v128 v; 607 M128A m; 608 } t; 609 t.v = r.getVectorRegister(UNW_X86_64_XMM0); 610 _msContext.Xmm0 = t.m; 611 t.v = r.getVectorRegister(UNW_X86_64_XMM1); 612 _msContext.Xmm1 = t.m; 613 t.v = r.getVectorRegister(UNW_X86_64_XMM2); 614 _msContext.Xmm2 = t.m; 615 t.v = r.getVectorRegister(UNW_X86_64_XMM3); 616 _msContext.Xmm3 = t.m; 617 t.v = r.getVectorRegister(UNW_X86_64_XMM4); 618 _msContext.Xmm4 = t.m; 619 t.v = r.getVectorRegister(UNW_X86_64_XMM5); 620 _msContext.Xmm5 = t.m; 621 t.v = r.getVectorRegister(UNW_X86_64_XMM6); 622 _msContext.Xmm6 = t.m; 623 t.v = r.getVectorRegister(UNW_X86_64_XMM7); 624 _msContext.Xmm7 = t.m; 625 t.v = r.getVectorRegister(UNW_X86_64_XMM8); 626 _msContext.Xmm8 = t.m; 627 t.v = r.getVectorRegister(UNW_X86_64_XMM9); 628 _msContext.Xmm9 = t.m; 629 t.v = r.getVectorRegister(UNW_X86_64_XMM10); 630 _msContext.Xmm10 = t.m; 631 t.v = r.getVectorRegister(UNW_X86_64_XMM11); 632 _msContext.Xmm11 = t.m; 633 t.v = r.getVectorRegister(UNW_X86_64_XMM12); 634 _msContext.Xmm12 = t.m; 635 t.v = r.getVectorRegister(UNW_X86_64_XMM13); 636 _msContext.Xmm13 = t.m; 637 t.v = r.getVectorRegister(UNW_X86_64_XMM14); 638 _msContext.Xmm14 = t.m; 639 t.v = r.getVectorRegister(UNW_X86_64_XMM15); 640 _msContext.Xmm15 = t.m; 641 #elif defined(_LIBUNWIND_TARGET_ARM) 642 _msContext.R0 = r.getRegister(UNW_ARM_R0); 643 _msContext.R1 = r.getRegister(UNW_ARM_R1); 644 _msContext.R2 = r.getRegister(UNW_ARM_R2); 645 _msContext.R3 = r.getRegister(UNW_ARM_R3); 646 _msContext.R4 = r.getRegister(UNW_ARM_R4); 647 _msContext.R5 = r.getRegister(UNW_ARM_R5); 648 _msContext.R6 = r.getRegister(UNW_ARM_R6); 649 _msContext.R7 = r.getRegister(UNW_ARM_R7); 650 _msContext.R8 = r.getRegister(UNW_ARM_R8); 651 _msContext.R9 = r.getRegister(UNW_ARM_R9); 652 _msContext.R10 = r.getRegister(UNW_ARM_R10); 653 _msContext.R11 = r.getRegister(UNW_ARM_R11); 654 _msContext.R12 = r.getRegister(UNW_ARM_R12); 655 _msContext.Sp = r.getRegister(UNW_ARM_SP); 656 _msContext.Lr = r.getRegister(UNW_ARM_LR); 657 _msContext.Pc = r.getRegister(UNW_ARM_IP); 658 for (int i = UNW_ARM_D0; i <= UNW_ARM_D31; ++i) { 659 union { 660 uint64_t w; 661 double d; 662 } d; 663 d.d = r.getFloatRegister(i); 664 _msContext.D[i - UNW_ARM_D0] = d.w; 665 } 666 #elif defined(_LIBUNWIND_TARGET_AARCH64) 667 for (int i = UNW_AARCH64_X0; i <= UNW_ARM64_X30; ++i) 668 _msContext.X[i - UNW_AARCH64_X0] = r.getRegister(i); 669 _msContext.Sp = r.getRegister(UNW_REG_SP); 670 _msContext.Pc = r.getRegister(UNW_REG_IP); 671 for (int i = UNW_AARCH64_V0; i <= UNW_ARM64_D31; ++i) 672 _msContext.V[i - UNW_AARCH64_V0].D[0] = r.getFloatRegister(i); 673 #endif 674 } 675 676 template <typename A, typename R> 677 UnwindCursor<A, R>::UnwindCursor(CONTEXT *context, A &as) 678 : _addressSpace(as), _unwindInfoMissing(false) { 679 static_assert((check_fit<UnwindCursor<A, R>, unw_cursor_t>::does_fit), 680 "UnwindCursor<> does not fit in unw_cursor_t"); 681 memset(&_info, 0, sizeof(_info)); 682 memset(&_histTable, 0, sizeof(_histTable)); 683 memset(&_dispContext, 0, sizeof(_dispContext)); 684 _dispContext.ContextRecord = &_msContext; 685 _dispContext.HistoryTable = &_histTable; 686 _msContext = *context; 687 } 688 689 690 template <typename A, typename R> 691 bool UnwindCursor<A, R>::validReg(int regNum) { 692 if (regNum == UNW_REG_IP || regNum == UNW_REG_SP) return true; 693 #if defined(_LIBUNWIND_TARGET_X86_64) 694 if (regNum >= UNW_X86_64_RAX && regNum <= UNW_X86_64_RIP) return true; 695 #elif defined(_LIBUNWIND_TARGET_ARM) 696 if ((regNum >= UNW_ARM_R0 && regNum <= UNW_ARM_R15) || 697 regNum == UNW_ARM_RA_AUTH_CODE) 698 return true; 699 #elif defined(_LIBUNWIND_TARGET_AARCH64) 700 if (regNum >= UNW_AARCH64_X0 && regNum <= UNW_ARM64_X30) return true; 701 #endif 702 return false; 703 } 704 705 template <typename A, typename R> 706 unw_word_t UnwindCursor<A, R>::getReg(int regNum) { 707 switch (regNum) { 708 #if defined(_LIBUNWIND_TARGET_X86_64) 709 case UNW_X86_64_RIP: 710 case UNW_REG_IP: return _msContext.Rip; 711 case UNW_X86_64_RAX: return _msContext.Rax; 712 case UNW_X86_64_RDX: return _msContext.Rdx; 713 case UNW_X86_64_RCX: return _msContext.Rcx; 714 case UNW_X86_64_RBX: return _msContext.Rbx; 715 case UNW_REG_SP: 716 case UNW_X86_64_RSP: return _msContext.Rsp; 717 case UNW_X86_64_RBP: return _msContext.Rbp; 718 case UNW_X86_64_RSI: return _msContext.Rsi; 719 case UNW_X86_64_RDI: return _msContext.Rdi; 720 case UNW_X86_64_R8: return _msContext.R8; 721 case UNW_X86_64_R9: return _msContext.R9; 722 case UNW_X86_64_R10: return _msContext.R10; 723 case UNW_X86_64_R11: return _msContext.R11; 724 case UNW_X86_64_R12: return _msContext.R12; 725 case UNW_X86_64_R13: return _msContext.R13; 726 case UNW_X86_64_R14: return _msContext.R14; 727 case UNW_X86_64_R15: return _msContext.R15; 728 #elif defined(_LIBUNWIND_TARGET_ARM) 729 case UNW_ARM_R0: return _msContext.R0; 730 case UNW_ARM_R1: return _msContext.R1; 731 case UNW_ARM_R2: return _msContext.R2; 732 case UNW_ARM_R3: return _msContext.R3; 733 case UNW_ARM_R4: return _msContext.R4; 734 case UNW_ARM_R5: return _msContext.R5; 735 case UNW_ARM_R6: return _msContext.R6; 736 case UNW_ARM_R7: return _msContext.R7; 737 case UNW_ARM_R8: return _msContext.R8; 738 case UNW_ARM_R9: return _msContext.R9; 739 case UNW_ARM_R10: return _msContext.R10; 740 case UNW_ARM_R11: return _msContext.R11; 741 case UNW_ARM_R12: return _msContext.R12; 742 case UNW_REG_SP: 743 case UNW_ARM_SP: return _msContext.Sp; 744 case UNW_ARM_LR: return _msContext.Lr; 745 case UNW_REG_IP: 746 case UNW_ARM_IP: return _msContext.Pc; 747 #elif defined(_LIBUNWIND_TARGET_AARCH64) 748 case UNW_REG_SP: return _msContext.Sp; 749 case UNW_REG_IP: return _msContext.Pc; 750 default: return _msContext.X[regNum - UNW_AARCH64_X0]; 751 #endif 752 } 753 _LIBUNWIND_ABORT("unsupported register"); 754 } 755 756 template <typename A, typename R> 757 void UnwindCursor<A, R>::setReg(int regNum, unw_word_t value) { 758 switch (regNum) { 759 #if defined(_LIBUNWIND_TARGET_X86_64) 760 case UNW_X86_64_RIP: 761 case UNW_REG_IP: _msContext.Rip = value; break; 762 case UNW_X86_64_RAX: _msContext.Rax = value; break; 763 case UNW_X86_64_RDX: _msContext.Rdx = value; break; 764 case UNW_X86_64_RCX: _msContext.Rcx = value; break; 765 case UNW_X86_64_RBX: _msContext.Rbx = value; break; 766 case UNW_REG_SP: 767 case UNW_X86_64_RSP: _msContext.Rsp = value; break; 768 case UNW_X86_64_RBP: _msContext.Rbp = value; break; 769 case UNW_X86_64_RSI: _msContext.Rsi = value; break; 770 case UNW_X86_64_RDI: _msContext.Rdi = value; break; 771 case UNW_X86_64_R8: _msContext.R8 = value; break; 772 case UNW_X86_64_R9: _msContext.R9 = value; break; 773 case UNW_X86_64_R10: _msContext.R10 = value; break; 774 case UNW_X86_64_R11: _msContext.R11 = value; break; 775 case UNW_X86_64_R12: _msContext.R12 = value; break; 776 case UNW_X86_64_R13: _msContext.R13 = value; break; 777 case UNW_X86_64_R14: _msContext.R14 = value; break; 778 case UNW_X86_64_R15: _msContext.R15 = value; break; 779 #elif defined(_LIBUNWIND_TARGET_ARM) 780 case UNW_ARM_R0: _msContext.R0 = value; break; 781 case UNW_ARM_R1: _msContext.R1 = value; break; 782 case UNW_ARM_R2: _msContext.R2 = value; break; 783 case UNW_ARM_R3: _msContext.R3 = value; break; 784 case UNW_ARM_R4: _msContext.R4 = value; break; 785 case UNW_ARM_R5: _msContext.R5 = value; break; 786 case UNW_ARM_R6: _msContext.R6 = value; break; 787 case UNW_ARM_R7: _msContext.R7 = value; break; 788 case UNW_ARM_R8: _msContext.R8 = value; break; 789 case UNW_ARM_R9: _msContext.R9 = value; break; 790 case UNW_ARM_R10: _msContext.R10 = value; break; 791 case UNW_ARM_R11: _msContext.R11 = value; break; 792 case UNW_ARM_R12: _msContext.R12 = value; break; 793 case UNW_REG_SP: 794 case UNW_ARM_SP: _msContext.Sp = value; break; 795 case UNW_ARM_LR: _msContext.Lr = value; break; 796 case UNW_REG_IP: 797 case UNW_ARM_IP: _msContext.Pc = value; break; 798 #elif defined(_LIBUNWIND_TARGET_AARCH64) 799 case UNW_REG_SP: _msContext.Sp = value; break; 800 case UNW_REG_IP: _msContext.Pc = value; break; 801 case UNW_AARCH64_X0: 802 case UNW_AARCH64_X1: 803 case UNW_AARCH64_X2: 804 case UNW_AARCH64_X3: 805 case UNW_AARCH64_X4: 806 case UNW_AARCH64_X5: 807 case UNW_AARCH64_X6: 808 case UNW_AARCH64_X7: 809 case UNW_AARCH64_X8: 810 case UNW_AARCH64_X9: 811 case UNW_AARCH64_X10: 812 case UNW_AARCH64_X11: 813 case UNW_AARCH64_X12: 814 case UNW_AARCH64_X13: 815 case UNW_AARCH64_X14: 816 case UNW_AARCH64_X15: 817 case UNW_AARCH64_X16: 818 case UNW_AARCH64_X17: 819 case UNW_AARCH64_X18: 820 case UNW_AARCH64_X19: 821 case UNW_AARCH64_X20: 822 case UNW_AARCH64_X21: 823 case UNW_AARCH64_X22: 824 case UNW_AARCH64_X23: 825 case UNW_AARCH64_X24: 826 case UNW_AARCH64_X25: 827 case UNW_AARCH64_X26: 828 case UNW_AARCH64_X27: 829 case UNW_AARCH64_X28: 830 case UNW_AARCH64_FP: 831 case UNW_AARCH64_LR: _msContext.X[regNum - UNW_ARM64_X0] = value; break; 832 #endif 833 default: 834 _LIBUNWIND_ABORT("unsupported register"); 835 } 836 } 837 838 template <typename A, typename R> 839 bool UnwindCursor<A, R>::validFloatReg(int regNum) { 840 #if defined(_LIBUNWIND_TARGET_ARM) 841 if (regNum >= UNW_ARM_S0 && regNum <= UNW_ARM_S31) return true; 842 if (regNum >= UNW_ARM_D0 && regNum <= UNW_ARM_D31) return true; 843 #elif defined(_LIBUNWIND_TARGET_AARCH64) 844 if (regNum >= UNW_AARCH64_V0 && regNum <= UNW_ARM64_D31) return true; 845 #else 846 (void)regNum; 847 #endif 848 return false; 849 } 850 851 template <typename A, typename R> 852 unw_fpreg_t UnwindCursor<A, R>::getFloatReg(int regNum) { 853 #if defined(_LIBUNWIND_TARGET_ARM) 854 if (regNum >= UNW_ARM_S0 && regNum <= UNW_ARM_S31) { 855 union { 856 uint32_t w; 857 float f; 858 } d; 859 d.w = _msContext.S[regNum - UNW_ARM_S0]; 860 return d.f; 861 } 862 if (regNum >= UNW_ARM_D0 && regNum <= UNW_ARM_D31) { 863 union { 864 uint64_t w; 865 double d; 866 } d; 867 d.w = _msContext.D[regNum - UNW_ARM_D0]; 868 return d.d; 869 } 870 _LIBUNWIND_ABORT("unsupported float register"); 871 #elif defined(_LIBUNWIND_TARGET_AARCH64) 872 return _msContext.V[regNum - UNW_AARCH64_V0].D[0]; 873 #else 874 (void)regNum; 875 _LIBUNWIND_ABORT("float registers unimplemented"); 876 #endif 877 } 878 879 template <typename A, typename R> 880 void UnwindCursor<A, R>::setFloatReg(int regNum, unw_fpreg_t value) { 881 #if defined(_LIBUNWIND_TARGET_ARM) 882 if (regNum >= UNW_ARM_S0 && regNum <= UNW_ARM_S31) { 883 union { 884 uint32_t w; 885 float f; 886 } d; 887 d.f = (float)value; 888 _msContext.S[regNum - UNW_ARM_S0] = d.w; 889 } 890 if (regNum >= UNW_ARM_D0 && regNum <= UNW_ARM_D31) { 891 union { 892 uint64_t w; 893 double d; 894 } d; 895 d.d = value; 896 _msContext.D[regNum - UNW_ARM_D0] = d.w; 897 } 898 _LIBUNWIND_ABORT("unsupported float register"); 899 #elif defined(_LIBUNWIND_TARGET_AARCH64) 900 _msContext.V[regNum - UNW_AARCH64_V0].D[0] = value; 901 #else 902 (void)regNum; 903 (void)value; 904 _LIBUNWIND_ABORT("float registers unimplemented"); 905 #endif 906 } 907 908 template <typename A, typename R> void UnwindCursor<A, R>::jumpto() { 909 RtlRestoreContext(&_msContext, nullptr); 910 } 911 912 #ifdef __arm__ 913 template <typename A, typename R> void UnwindCursor<A, R>::saveVFPAsX() {} 914 #endif 915 916 template <typename A, typename R> 917 const char *UnwindCursor<A, R>::getRegisterName(int regNum) { 918 return R::getRegisterName(regNum); 919 } 920 921 template <typename A, typename R> bool UnwindCursor<A, R>::isSignalFrame() { 922 return false; 923 } 924 925 #else // !defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) || !defined(_WIN32) 926 927 /// UnwindCursor contains all state (including all register values) during 928 /// an unwind. This is normally stack allocated inside a unw_cursor_t. 929 template <typename A, typename R> 930 class UnwindCursor : public AbstractUnwindCursor{ 931 typedef typename A::pint_t pint_t; 932 public: 933 UnwindCursor(unw_context_t *context, A &as); 934 UnwindCursor(A &as, void *threadArg); 935 virtual ~UnwindCursor() {} 936 virtual bool validReg(int); 937 virtual unw_word_t getReg(int); 938 virtual void setReg(int, unw_word_t); 939 virtual bool validFloatReg(int); 940 virtual unw_fpreg_t getFloatReg(int); 941 virtual void setFloatReg(int, unw_fpreg_t); 942 virtual int step(bool stage2 = false); 943 virtual void getInfo(unw_proc_info_t *); 944 virtual void jumpto(); 945 virtual bool isSignalFrame(); 946 virtual bool getFunctionName(char *buf, size_t len, unw_word_t *off); 947 virtual void setInfoBasedOnIPRegister(bool isReturnAddress = false); 948 virtual const char *getRegisterName(int num); 949 #ifdef __arm__ 950 virtual void saveVFPAsX(); 951 #endif 952 953 #ifdef _AIX 954 virtual uintptr_t getDataRelBase(); 955 #endif 956 957 #if defined(_LIBUNWIND_USE_CET) 958 virtual void *get_registers() { return &_registers; } 959 #endif 960 961 // libunwind does not and should not depend on C++ library which means that we 962 // need our own definition of inline placement new. 963 static void *operator new(size_t, UnwindCursor<A, R> *p) { return p; } 964 965 private: 966 967 #if defined(_LIBUNWIND_ARM_EHABI) 968 bool getInfoFromEHABISection(pint_t pc, const UnwindInfoSections §s); 969 970 int stepWithEHABI() { 971 size_t len = 0; 972 size_t off = 0; 973 // FIXME: Calling decode_eht_entry() here is violating the libunwind 974 // abstraction layer. 975 const uint32_t *ehtp = 976 decode_eht_entry(reinterpret_cast<const uint32_t *>(_info.unwind_info), 977 &off, &len); 978 if (_Unwind_VRS_Interpret((_Unwind_Context *)this, ehtp, off, len) != 979 _URC_CONTINUE_UNWIND) 980 return UNW_STEP_END; 981 return UNW_STEP_SUCCESS; 982 } 983 #endif 984 985 #if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) 986 bool setInfoForSigReturn() { 987 R dummy; 988 return setInfoForSigReturn(dummy); 989 } 990 int stepThroughSigReturn() { 991 R dummy; 992 return stepThroughSigReturn(dummy); 993 } 994 bool isReadableAddr(const pint_t addr) const; 995 #if defined(_LIBUNWIND_TARGET_AARCH64) 996 bool setInfoForSigReturn(Registers_arm64 &); 997 int stepThroughSigReturn(Registers_arm64 &); 998 #endif 999 #if defined(_LIBUNWIND_TARGET_RISCV) 1000 bool setInfoForSigReturn(Registers_riscv &); 1001 int stepThroughSigReturn(Registers_riscv &); 1002 #endif 1003 #if defined(_LIBUNWIND_TARGET_S390X) 1004 bool setInfoForSigReturn(Registers_s390x &); 1005 int stepThroughSigReturn(Registers_s390x &); 1006 #endif 1007 template <typename Registers> bool setInfoForSigReturn(Registers &) { 1008 return false; 1009 } 1010 template <typename Registers> int stepThroughSigReturn(Registers &) { 1011 return UNW_STEP_END; 1012 } 1013 #endif 1014 1015 #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 1016 bool getInfoFromFdeCie(const typename CFI_Parser<A>::FDE_Info &fdeInfo, 1017 const typename CFI_Parser<A>::CIE_Info &cieInfo, 1018 pint_t pc, uintptr_t dso_base); 1019 bool getInfoFromDwarfSection(pint_t pc, const UnwindInfoSections §s, 1020 uint32_t fdeSectionOffsetHint=0); 1021 int stepWithDwarfFDE(bool stage2) { 1022 return DwarfInstructions<A, R>::stepWithDwarf( 1023 _addressSpace, (pint_t)this->getReg(UNW_REG_IP), 1024 (pint_t)_info.unwind_info, _registers, _isSignalFrame, stage2); 1025 } 1026 #endif 1027 1028 #if defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND) 1029 bool getInfoFromCompactEncodingSection(pint_t pc, 1030 const UnwindInfoSections §s); 1031 int stepWithCompactEncoding(bool stage2 = false) { 1032 #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 1033 if ( compactSaysUseDwarf() ) 1034 return stepWithDwarfFDE(stage2); 1035 #endif 1036 R dummy; 1037 return stepWithCompactEncoding(dummy); 1038 } 1039 1040 #if defined(_LIBUNWIND_TARGET_X86_64) 1041 int stepWithCompactEncoding(Registers_x86_64 &) { 1042 return CompactUnwinder_x86_64<A>::stepWithCompactEncoding( 1043 _info.format, _info.start_ip, _addressSpace, _registers); 1044 } 1045 #endif 1046 1047 #if defined(_LIBUNWIND_TARGET_I386) 1048 int stepWithCompactEncoding(Registers_x86 &) { 1049 return CompactUnwinder_x86<A>::stepWithCompactEncoding( 1050 _info.format, (uint32_t)_info.start_ip, _addressSpace, _registers); 1051 } 1052 #endif 1053 1054 #if defined(_LIBUNWIND_TARGET_PPC) 1055 int stepWithCompactEncoding(Registers_ppc &) { 1056 return UNW_EINVAL; 1057 } 1058 #endif 1059 1060 #if defined(_LIBUNWIND_TARGET_PPC64) 1061 int stepWithCompactEncoding(Registers_ppc64 &) { 1062 return UNW_EINVAL; 1063 } 1064 #endif 1065 1066 1067 #if defined(_LIBUNWIND_TARGET_AARCH64) 1068 int stepWithCompactEncoding(Registers_arm64 &) { 1069 return CompactUnwinder_arm64<A>::stepWithCompactEncoding( 1070 _info.format, _info.start_ip, _addressSpace, _registers); 1071 } 1072 #endif 1073 1074 #if defined(_LIBUNWIND_TARGET_MIPS_O32) 1075 int stepWithCompactEncoding(Registers_mips_o32 &) { 1076 return UNW_EINVAL; 1077 } 1078 #endif 1079 1080 #if defined(_LIBUNWIND_TARGET_MIPS_NEWABI) 1081 int stepWithCompactEncoding(Registers_mips_newabi &) { 1082 return UNW_EINVAL; 1083 } 1084 #endif 1085 1086 #if defined(_LIBUNWIND_TARGET_LOONGARCH) 1087 int stepWithCompactEncoding(Registers_loongarch &) { return UNW_EINVAL; } 1088 #endif 1089 1090 #if defined(_LIBUNWIND_TARGET_SPARC) 1091 int stepWithCompactEncoding(Registers_sparc &) { return UNW_EINVAL; } 1092 #endif 1093 1094 #if defined(_LIBUNWIND_TARGET_SPARC64) 1095 int stepWithCompactEncoding(Registers_sparc64 &) { return UNW_EINVAL; } 1096 #endif 1097 1098 #if defined (_LIBUNWIND_TARGET_RISCV) 1099 int stepWithCompactEncoding(Registers_riscv &) { 1100 return UNW_EINVAL; 1101 } 1102 #endif 1103 1104 bool compactSaysUseDwarf(uint32_t *offset=NULL) const { 1105 R dummy; 1106 return compactSaysUseDwarf(dummy, offset); 1107 } 1108 1109 #if defined(_LIBUNWIND_TARGET_X86_64) 1110 bool compactSaysUseDwarf(Registers_x86_64 &, uint32_t *offset) const { 1111 if ((_info.format & UNWIND_X86_64_MODE_MASK) == UNWIND_X86_64_MODE_DWARF) { 1112 if (offset) 1113 *offset = (_info.format & UNWIND_X86_64_DWARF_SECTION_OFFSET); 1114 return true; 1115 } 1116 return false; 1117 } 1118 #endif 1119 1120 #if defined(_LIBUNWIND_TARGET_I386) 1121 bool compactSaysUseDwarf(Registers_x86 &, uint32_t *offset) const { 1122 if ((_info.format & UNWIND_X86_MODE_MASK) == UNWIND_X86_MODE_DWARF) { 1123 if (offset) 1124 *offset = (_info.format & UNWIND_X86_DWARF_SECTION_OFFSET); 1125 return true; 1126 } 1127 return false; 1128 } 1129 #endif 1130 1131 #if defined(_LIBUNWIND_TARGET_PPC) 1132 bool compactSaysUseDwarf(Registers_ppc &, uint32_t *) const { 1133 return true; 1134 } 1135 #endif 1136 1137 #if defined(_LIBUNWIND_TARGET_PPC64) 1138 bool compactSaysUseDwarf(Registers_ppc64 &, uint32_t *) const { 1139 return true; 1140 } 1141 #endif 1142 1143 #if defined(_LIBUNWIND_TARGET_AARCH64) 1144 bool compactSaysUseDwarf(Registers_arm64 &, uint32_t *offset) const { 1145 if ((_info.format & UNWIND_ARM64_MODE_MASK) == UNWIND_ARM64_MODE_DWARF) { 1146 if (offset) 1147 *offset = (_info.format & UNWIND_ARM64_DWARF_SECTION_OFFSET); 1148 return true; 1149 } 1150 return false; 1151 } 1152 #endif 1153 1154 #if defined(_LIBUNWIND_TARGET_MIPS_O32) 1155 bool compactSaysUseDwarf(Registers_mips_o32 &, uint32_t *) const { 1156 return true; 1157 } 1158 #endif 1159 1160 #if defined(_LIBUNWIND_TARGET_MIPS_NEWABI) 1161 bool compactSaysUseDwarf(Registers_mips_newabi &, uint32_t *) const { 1162 return true; 1163 } 1164 #endif 1165 1166 #if defined(_LIBUNWIND_TARGET_LOONGARCH) 1167 bool compactSaysUseDwarf(Registers_loongarch &, uint32_t *) const { 1168 return true; 1169 } 1170 #endif 1171 1172 #if defined(_LIBUNWIND_TARGET_SPARC) 1173 bool compactSaysUseDwarf(Registers_sparc &, uint32_t *) const { return true; } 1174 #endif 1175 1176 #if defined(_LIBUNWIND_TARGET_SPARC64) 1177 bool compactSaysUseDwarf(Registers_sparc64 &, uint32_t *) const { 1178 return true; 1179 } 1180 #endif 1181 1182 #if defined (_LIBUNWIND_TARGET_RISCV) 1183 bool compactSaysUseDwarf(Registers_riscv &, uint32_t *) const { 1184 return true; 1185 } 1186 #endif 1187 1188 #endif // defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND) 1189 1190 #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 1191 compact_unwind_encoding_t dwarfEncoding() const { 1192 R dummy; 1193 return dwarfEncoding(dummy); 1194 } 1195 1196 #if defined(_LIBUNWIND_TARGET_X86_64) 1197 compact_unwind_encoding_t dwarfEncoding(Registers_x86_64 &) const { 1198 return UNWIND_X86_64_MODE_DWARF; 1199 } 1200 #endif 1201 1202 #if defined(_LIBUNWIND_TARGET_I386) 1203 compact_unwind_encoding_t dwarfEncoding(Registers_x86 &) const { 1204 return UNWIND_X86_MODE_DWARF; 1205 } 1206 #endif 1207 1208 #if defined(_LIBUNWIND_TARGET_PPC) 1209 compact_unwind_encoding_t dwarfEncoding(Registers_ppc &) const { 1210 return 0; 1211 } 1212 #endif 1213 1214 #if defined(_LIBUNWIND_TARGET_PPC64) 1215 compact_unwind_encoding_t dwarfEncoding(Registers_ppc64 &) const { 1216 return 0; 1217 } 1218 #endif 1219 1220 #if defined(_LIBUNWIND_TARGET_AARCH64) 1221 compact_unwind_encoding_t dwarfEncoding(Registers_arm64 &) const { 1222 return UNWIND_ARM64_MODE_DWARF; 1223 } 1224 #endif 1225 1226 #if defined(_LIBUNWIND_TARGET_ARM) 1227 compact_unwind_encoding_t dwarfEncoding(Registers_arm &) const { 1228 return 0; 1229 } 1230 #endif 1231 1232 #if defined (_LIBUNWIND_TARGET_OR1K) 1233 compact_unwind_encoding_t dwarfEncoding(Registers_or1k &) const { 1234 return 0; 1235 } 1236 #endif 1237 1238 #if defined (_LIBUNWIND_TARGET_HEXAGON) 1239 compact_unwind_encoding_t dwarfEncoding(Registers_hexagon &) const { 1240 return 0; 1241 } 1242 #endif 1243 1244 #if defined (_LIBUNWIND_TARGET_MIPS_O32) 1245 compact_unwind_encoding_t dwarfEncoding(Registers_mips_o32 &) const { 1246 return 0; 1247 } 1248 #endif 1249 1250 #if defined (_LIBUNWIND_TARGET_MIPS_NEWABI) 1251 compact_unwind_encoding_t dwarfEncoding(Registers_mips_newabi &) const { 1252 return 0; 1253 } 1254 #endif 1255 1256 #if defined(_LIBUNWIND_TARGET_LOONGARCH) 1257 compact_unwind_encoding_t dwarfEncoding(Registers_loongarch &) const { 1258 return 0; 1259 } 1260 #endif 1261 1262 #if defined(_LIBUNWIND_TARGET_SPARC) 1263 compact_unwind_encoding_t dwarfEncoding(Registers_sparc &) const { return 0; } 1264 #endif 1265 1266 #if defined(_LIBUNWIND_TARGET_SPARC64) 1267 compact_unwind_encoding_t dwarfEncoding(Registers_sparc64 &) const { 1268 return 0; 1269 } 1270 #endif 1271 1272 #if defined (_LIBUNWIND_TARGET_RISCV) 1273 compact_unwind_encoding_t dwarfEncoding(Registers_riscv &) const { 1274 return 0; 1275 } 1276 #endif 1277 1278 #if defined (_LIBUNWIND_TARGET_S390X) 1279 compact_unwind_encoding_t dwarfEncoding(Registers_s390x &) const { 1280 return 0; 1281 } 1282 #endif 1283 1284 #endif // defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 1285 1286 #if defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) 1287 // For runtime environments using SEH unwind data without Windows runtime 1288 // support. 1289 pint_t getLastPC() const { /* FIXME: Implement */ return 0; } 1290 void setLastPC(pint_t pc) { /* FIXME: Implement */ } 1291 RUNTIME_FUNCTION *lookUpSEHUnwindInfo(pint_t pc, pint_t *base) { 1292 /* FIXME: Implement */ 1293 *base = 0; 1294 return nullptr; 1295 } 1296 bool getInfoFromSEH(pint_t pc); 1297 int stepWithSEHData() { /* FIXME: Implement */ return 0; } 1298 #endif // defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) 1299 1300 #if defined(_LIBUNWIND_SUPPORT_TBTAB_UNWIND) 1301 bool getInfoFromTBTable(pint_t pc, R ®isters); 1302 int stepWithTBTable(pint_t pc, tbtable *TBTable, R ®isters, 1303 bool &isSignalFrame); 1304 int stepWithTBTableData() { 1305 return stepWithTBTable(reinterpret_cast<pint_t>(this->getReg(UNW_REG_IP)), 1306 reinterpret_cast<tbtable *>(_info.unwind_info), 1307 _registers, _isSignalFrame); 1308 } 1309 #endif // defined(_LIBUNWIND_SUPPORT_TBTAB_UNWIND) 1310 1311 A &_addressSpace; 1312 R _registers; 1313 unw_proc_info_t _info; 1314 bool _unwindInfoMissing; 1315 bool _isSignalFrame; 1316 #if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) 1317 bool _isSigReturn = false; 1318 #endif 1319 }; 1320 1321 1322 template <typename A, typename R> 1323 UnwindCursor<A, R>::UnwindCursor(unw_context_t *context, A &as) 1324 : _addressSpace(as), _registers(context), _unwindInfoMissing(false), 1325 _isSignalFrame(false) { 1326 static_assert((check_fit<UnwindCursor<A, R>, unw_cursor_t>::does_fit), 1327 "UnwindCursor<> does not fit in unw_cursor_t"); 1328 static_assert((alignof(UnwindCursor<A, R>) <= alignof(unw_cursor_t)), 1329 "UnwindCursor<> requires more alignment than unw_cursor_t"); 1330 memset(&_info, 0, sizeof(_info)); 1331 } 1332 1333 template <typename A, typename R> 1334 UnwindCursor<A, R>::UnwindCursor(A &as, void *) 1335 : _addressSpace(as), _unwindInfoMissing(false), _isSignalFrame(false) { 1336 memset(&_info, 0, sizeof(_info)); 1337 // FIXME 1338 // fill in _registers from thread arg 1339 } 1340 1341 1342 template <typename A, typename R> 1343 bool UnwindCursor<A, R>::validReg(int regNum) { 1344 return _registers.validRegister(regNum); 1345 } 1346 1347 template <typename A, typename R> 1348 unw_word_t UnwindCursor<A, R>::getReg(int regNum) { 1349 return _registers.getRegister(regNum); 1350 } 1351 1352 template <typename A, typename R> 1353 void UnwindCursor<A, R>::setReg(int regNum, unw_word_t value) { 1354 _registers.setRegister(regNum, (typename A::pint_t)value); 1355 } 1356 1357 template <typename A, typename R> 1358 bool UnwindCursor<A, R>::validFloatReg(int regNum) { 1359 return _registers.validFloatRegister(regNum); 1360 } 1361 1362 template <typename A, typename R> 1363 unw_fpreg_t UnwindCursor<A, R>::getFloatReg(int regNum) { 1364 return _registers.getFloatRegister(regNum); 1365 } 1366 1367 template <typename A, typename R> 1368 void UnwindCursor<A, R>::setFloatReg(int regNum, unw_fpreg_t value) { 1369 _registers.setFloatRegister(regNum, value); 1370 } 1371 1372 template <typename A, typename R> void UnwindCursor<A, R>::jumpto() { 1373 _registers.jumpto(); 1374 } 1375 1376 #ifdef __arm__ 1377 template <typename A, typename R> void UnwindCursor<A, R>::saveVFPAsX() { 1378 _registers.saveVFPAsX(); 1379 } 1380 #endif 1381 1382 #ifdef _AIX 1383 template <typename A, typename R> 1384 uintptr_t UnwindCursor<A, R>::getDataRelBase() { 1385 return reinterpret_cast<uintptr_t>(_info.extra); 1386 } 1387 #endif 1388 1389 template <typename A, typename R> 1390 const char *UnwindCursor<A, R>::getRegisterName(int regNum) { 1391 return _registers.getRegisterName(regNum); 1392 } 1393 1394 template <typename A, typename R> bool UnwindCursor<A, R>::isSignalFrame() { 1395 return _isSignalFrame; 1396 } 1397 1398 #endif // defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) 1399 1400 #if defined(_LIBUNWIND_ARM_EHABI) 1401 template<typename A> 1402 struct EHABISectionIterator { 1403 typedef EHABISectionIterator _Self; 1404 1405 typedef typename A::pint_t value_type; 1406 typedef typename A::pint_t* pointer; 1407 typedef typename A::pint_t& reference; 1408 typedef size_t size_type; 1409 typedef size_t difference_type; 1410 1411 static _Self begin(A& addressSpace, const UnwindInfoSections& sects) { 1412 return _Self(addressSpace, sects, 0); 1413 } 1414 static _Self end(A& addressSpace, const UnwindInfoSections& sects) { 1415 return _Self(addressSpace, sects, 1416 sects.arm_section_length / sizeof(EHABIIndexEntry)); 1417 } 1418 1419 EHABISectionIterator(A& addressSpace, const UnwindInfoSections& sects, size_t i) 1420 : _i(i), _addressSpace(&addressSpace), _sects(§s) {} 1421 1422 _Self& operator++() { ++_i; return *this; } 1423 _Self& operator+=(size_t a) { _i += a; return *this; } 1424 _Self& operator--() { assert(_i > 0); --_i; return *this; } 1425 _Self& operator-=(size_t a) { assert(_i >= a); _i -= a; return *this; } 1426 1427 _Self operator+(size_t a) { _Self out = *this; out._i += a; return out; } 1428 _Self operator-(size_t a) { assert(_i >= a); _Self out = *this; out._i -= a; return out; } 1429 1430 size_t operator-(const _Self& other) const { return _i - other._i; } 1431 1432 bool operator==(const _Self& other) const { 1433 assert(_addressSpace == other._addressSpace); 1434 assert(_sects == other._sects); 1435 return _i == other._i; 1436 } 1437 1438 bool operator!=(const _Self& other) const { 1439 assert(_addressSpace == other._addressSpace); 1440 assert(_sects == other._sects); 1441 return _i != other._i; 1442 } 1443 1444 typename A::pint_t operator*() const { return functionAddress(); } 1445 1446 typename A::pint_t functionAddress() const { 1447 typename A::pint_t indexAddr = _sects->arm_section + arrayoffsetof( 1448 EHABIIndexEntry, _i, functionOffset); 1449 return indexAddr + signExtendPrel31(_addressSpace->get32(indexAddr)); 1450 } 1451 1452 typename A::pint_t dataAddress() { 1453 typename A::pint_t indexAddr = _sects->arm_section + arrayoffsetof( 1454 EHABIIndexEntry, _i, data); 1455 return indexAddr; 1456 } 1457 1458 private: 1459 size_t _i; 1460 A* _addressSpace; 1461 const UnwindInfoSections* _sects; 1462 }; 1463 1464 namespace { 1465 1466 template <typename A> 1467 EHABISectionIterator<A> EHABISectionUpperBound( 1468 EHABISectionIterator<A> first, 1469 EHABISectionIterator<A> last, 1470 typename A::pint_t value) { 1471 size_t len = last - first; 1472 while (len > 0) { 1473 size_t l2 = len / 2; 1474 EHABISectionIterator<A> m = first + l2; 1475 if (value < *m) { 1476 len = l2; 1477 } else { 1478 first = ++m; 1479 len -= l2 + 1; 1480 } 1481 } 1482 return first; 1483 } 1484 1485 } 1486 1487 template <typename A, typename R> 1488 bool UnwindCursor<A, R>::getInfoFromEHABISection( 1489 pint_t pc, 1490 const UnwindInfoSections §s) { 1491 EHABISectionIterator<A> begin = 1492 EHABISectionIterator<A>::begin(_addressSpace, sects); 1493 EHABISectionIterator<A> end = 1494 EHABISectionIterator<A>::end(_addressSpace, sects); 1495 if (begin == end) 1496 return false; 1497 1498 EHABISectionIterator<A> itNextPC = EHABISectionUpperBound(begin, end, pc); 1499 if (itNextPC == begin) 1500 return false; 1501 EHABISectionIterator<A> itThisPC = itNextPC - 1; 1502 1503 pint_t thisPC = itThisPC.functionAddress(); 1504 // If an exception is thrown from a function, corresponding to the last entry 1505 // in the table, we don't really know the function extent and have to choose a 1506 // value for nextPC. Choosing max() will allow the range check during trace to 1507 // succeed. 1508 pint_t nextPC = (itNextPC == end) ? UINTPTR_MAX : itNextPC.functionAddress(); 1509 pint_t indexDataAddr = itThisPC.dataAddress(); 1510 1511 if (indexDataAddr == 0) 1512 return false; 1513 1514 uint32_t indexData = _addressSpace.get32(indexDataAddr); 1515 if (indexData == UNW_EXIDX_CANTUNWIND) 1516 return false; 1517 1518 // If the high bit is set, the exception handling table entry is inline inside 1519 // the index table entry on the second word (aka |indexDataAddr|). Otherwise, 1520 // the table points at an offset in the exception handling table (section 5 1521 // EHABI). 1522 pint_t exceptionTableAddr; 1523 uint32_t exceptionTableData; 1524 bool isSingleWordEHT; 1525 if (indexData & 0x80000000) { 1526 exceptionTableAddr = indexDataAddr; 1527 // TODO(ajwong): Should this data be 0? 1528 exceptionTableData = indexData; 1529 isSingleWordEHT = true; 1530 } else { 1531 exceptionTableAddr = indexDataAddr + signExtendPrel31(indexData); 1532 exceptionTableData = _addressSpace.get32(exceptionTableAddr); 1533 isSingleWordEHT = false; 1534 } 1535 1536 // Now we know the 3 things: 1537 // exceptionTableAddr -- exception handler table entry. 1538 // exceptionTableData -- the data inside the first word of the eht entry. 1539 // isSingleWordEHT -- whether the entry is in the index. 1540 unw_word_t personalityRoutine = 0xbadf00d; 1541 bool scope32 = false; 1542 uintptr_t lsda; 1543 1544 // If the high bit in the exception handling table entry is set, the entry is 1545 // in compact form (section 6.3 EHABI). 1546 if (exceptionTableData & 0x80000000) { 1547 // Grab the index of the personality routine from the compact form. 1548 uint32_t choice = (exceptionTableData & 0x0f000000) >> 24; 1549 uint32_t extraWords = 0; 1550 switch (choice) { 1551 case 0: 1552 personalityRoutine = (unw_word_t) &__aeabi_unwind_cpp_pr0; 1553 extraWords = 0; 1554 scope32 = false; 1555 lsda = isSingleWordEHT ? 0 : (exceptionTableAddr + 4); 1556 break; 1557 case 1: 1558 personalityRoutine = (unw_word_t) &__aeabi_unwind_cpp_pr1; 1559 extraWords = (exceptionTableData & 0x00ff0000) >> 16; 1560 scope32 = false; 1561 lsda = exceptionTableAddr + (extraWords + 1) * 4; 1562 break; 1563 case 2: 1564 personalityRoutine = (unw_word_t) &__aeabi_unwind_cpp_pr2; 1565 extraWords = (exceptionTableData & 0x00ff0000) >> 16; 1566 scope32 = true; 1567 lsda = exceptionTableAddr + (extraWords + 1) * 4; 1568 break; 1569 default: 1570 _LIBUNWIND_ABORT("unknown personality routine"); 1571 return false; 1572 } 1573 1574 if (isSingleWordEHT) { 1575 if (extraWords != 0) { 1576 _LIBUNWIND_ABORT("index inlined table detected but pr function " 1577 "requires extra words"); 1578 return false; 1579 } 1580 } 1581 } else { 1582 pint_t personalityAddr = 1583 exceptionTableAddr + signExtendPrel31(exceptionTableData); 1584 personalityRoutine = personalityAddr; 1585 1586 // ARM EHABI # 6.2, # 9.2 1587 // 1588 // +---- ehtp 1589 // v 1590 // +--------------------------------------+ 1591 // | +--------+--------+--------+-------+ | 1592 // | |0| prel31 to personalityRoutine | | 1593 // | +--------+--------+--------+-------+ | 1594 // | | N | unwind opcodes | | <-- UnwindData 1595 // | +--------+--------+--------+-------+ | 1596 // | | Word 2 unwind opcodes | | 1597 // | +--------+--------+--------+-------+ | 1598 // | ... | 1599 // | +--------+--------+--------+-------+ | 1600 // | | Word N unwind opcodes | | 1601 // | +--------+--------+--------+-------+ | 1602 // | | LSDA | | <-- lsda 1603 // | | ... | | 1604 // | +--------+--------+--------+-------+ | 1605 // +--------------------------------------+ 1606 1607 uint32_t *UnwindData = reinterpret_cast<uint32_t*>(exceptionTableAddr) + 1; 1608 uint32_t FirstDataWord = *UnwindData; 1609 size_t N = ((FirstDataWord >> 24) & 0xff); 1610 size_t NDataWords = N + 1; 1611 lsda = reinterpret_cast<uintptr_t>(UnwindData + NDataWords); 1612 } 1613 1614 _info.start_ip = thisPC; 1615 _info.end_ip = nextPC; 1616 _info.handler = personalityRoutine; 1617 _info.unwind_info = exceptionTableAddr; 1618 _info.lsda = lsda; 1619 // flags is pr_cache.additional. See EHABI #7.2 for definition of bit 0. 1620 _info.flags = (isSingleWordEHT ? 1 : 0) | (scope32 ? 0x2 : 0); // Use enum? 1621 1622 return true; 1623 } 1624 #endif 1625 1626 #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 1627 template <typename A, typename R> 1628 bool UnwindCursor<A, R>::getInfoFromFdeCie( 1629 const typename CFI_Parser<A>::FDE_Info &fdeInfo, 1630 const typename CFI_Parser<A>::CIE_Info &cieInfo, pint_t pc, 1631 uintptr_t dso_base) { 1632 typename CFI_Parser<A>::PrologInfo prolog; 1633 if (CFI_Parser<A>::parseFDEInstructions(_addressSpace, fdeInfo, cieInfo, pc, 1634 R::getArch(), &prolog)) { 1635 // Save off parsed FDE info 1636 _info.start_ip = fdeInfo.pcStart; 1637 _info.end_ip = fdeInfo.pcEnd; 1638 _info.lsda = fdeInfo.lsda; 1639 _info.handler = cieInfo.personality; 1640 // Some frameless functions need SP altered when resuming in function, so 1641 // propagate spExtraArgSize. 1642 _info.gp = prolog.spExtraArgSize; 1643 _info.flags = 0; 1644 _info.format = dwarfEncoding(); 1645 _info.unwind_info = fdeInfo.fdeStart; 1646 _info.unwind_info_size = static_cast<uint32_t>(fdeInfo.fdeLength); 1647 _info.extra = static_cast<unw_word_t>(dso_base); 1648 return true; 1649 } 1650 return false; 1651 } 1652 1653 template <typename A, typename R> 1654 bool UnwindCursor<A, R>::getInfoFromDwarfSection(pint_t pc, 1655 const UnwindInfoSections §s, 1656 uint32_t fdeSectionOffsetHint) { 1657 typename CFI_Parser<A>::FDE_Info fdeInfo; 1658 typename CFI_Parser<A>::CIE_Info cieInfo; 1659 bool foundFDE = false; 1660 bool foundInCache = false; 1661 // If compact encoding table gave offset into dwarf section, go directly there 1662 if (fdeSectionOffsetHint != 0) { 1663 foundFDE = CFI_Parser<A>::findFDE(_addressSpace, pc, sects.dwarf_section, 1664 sects.dwarf_section_length, 1665 sects.dwarf_section + fdeSectionOffsetHint, 1666 &fdeInfo, &cieInfo); 1667 } 1668 #if defined(_LIBUNWIND_SUPPORT_DWARF_INDEX) 1669 if (!foundFDE && (sects.dwarf_index_section != 0)) { 1670 foundFDE = EHHeaderParser<A>::findFDE( 1671 _addressSpace, pc, sects.dwarf_index_section, 1672 (uint32_t)sects.dwarf_index_section_length, &fdeInfo, &cieInfo); 1673 } 1674 #endif 1675 if (!foundFDE) { 1676 // otherwise, search cache of previously found FDEs. 1677 pint_t cachedFDE = DwarfFDECache<A>::findFDE(sects.dso_base, pc); 1678 if (cachedFDE != 0) { 1679 foundFDE = 1680 CFI_Parser<A>::findFDE(_addressSpace, pc, sects.dwarf_section, 1681 sects.dwarf_section_length, 1682 cachedFDE, &fdeInfo, &cieInfo); 1683 foundInCache = foundFDE; 1684 } 1685 } 1686 if (!foundFDE) { 1687 // Still not found, do full scan of __eh_frame section. 1688 foundFDE = CFI_Parser<A>::findFDE(_addressSpace, pc, sects.dwarf_section, 1689 sects.dwarf_section_length, 0, 1690 &fdeInfo, &cieInfo); 1691 } 1692 if (foundFDE) { 1693 if (getInfoFromFdeCie(fdeInfo, cieInfo, pc, sects.dso_base)) { 1694 // Add to cache (to make next lookup faster) if we had no hint 1695 // and there was no index. 1696 if (!foundInCache && (fdeSectionOffsetHint == 0)) { 1697 #if defined(_LIBUNWIND_SUPPORT_DWARF_INDEX) 1698 if (sects.dwarf_index_section == 0) 1699 #endif 1700 DwarfFDECache<A>::add(sects.dso_base, fdeInfo.pcStart, fdeInfo.pcEnd, 1701 fdeInfo.fdeStart); 1702 } 1703 return true; 1704 } 1705 } 1706 //_LIBUNWIND_DEBUG_LOG("can't find/use FDE for pc=0x%llX", (uint64_t)pc); 1707 return false; 1708 } 1709 #endif // defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 1710 1711 1712 #if defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND) 1713 template <typename A, typename R> 1714 bool UnwindCursor<A, R>::getInfoFromCompactEncodingSection(pint_t pc, 1715 const UnwindInfoSections §s) { 1716 const bool log = false; 1717 if (log) 1718 fprintf(stderr, "getInfoFromCompactEncodingSection(pc=0x%llX, mh=0x%llX)\n", 1719 (uint64_t)pc, (uint64_t)sects.dso_base); 1720 1721 const UnwindSectionHeader<A> sectionHeader(_addressSpace, 1722 sects.compact_unwind_section); 1723 if (sectionHeader.version() != UNWIND_SECTION_VERSION) 1724 return false; 1725 1726 // do a binary search of top level index to find page with unwind info 1727 pint_t targetFunctionOffset = pc - sects.dso_base; 1728 const UnwindSectionIndexArray<A> topIndex(_addressSpace, 1729 sects.compact_unwind_section 1730 + sectionHeader.indexSectionOffset()); 1731 uint32_t low = 0; 1732 uint32_t high = sectionHeader.indexCount(); 1733 uint32_t last = high - 1; 1734 while (low < high) { 1735 uint32_t mid = (low + high) / 2; 1736 //if ( log ) fprintf(stderr, "\tmid=%d, low=%d, high=%d, *mid=0x%08X\n", 1737 //mid, low, high, topIndex.functionOffset(mid)); 1738 if (topIndex.functionOffset(mid) <= targetFunctionOffset) { 1739 if ((mid == last) || 1740 (topIndex.functionOffset(mid + 1) > targetFunctionOffset)) { 1741 low = mid; 1742 break; 1743 } else { 1744 low = mid + 1; 1745 } 1746 } else { 1747 high = mid; 1748 } 1749 } 1750 const uint32_t firstLevelFunctionOffset = topIndex.functionOffset(low); 1751 const uint32_t firstLevelNextPageFunctionOffset = 1752 topIndex.functionOffset(low + 1); 1753 const pint_t secondLevelAddr = 1754 sects.compact_unwind_section + topIndex.secondLevelPagesSectionOffset(low); 1755 const pint_t lsdaArrayStartAddr = 1756 sects.compact_unwind_section + topIndex.lsdaIndexArraySectionOffset(low); 1757 const pint_t lsdaArrayEndAddr = 1758 sects.compact_unwind_section + topIndex.lsdaIndexArraySectionOffset(low+1); 1759 if (log) 1760 fprintf(stderr, "\tfirst level search for result index=%d " 1761 "to secondLevelAddr=0x%llX\n", 1762 low, (uint64_t) secondLevelAddr); 1763 // do a binary search of second level page index 1764 uint32_t encoding = 0; 1765 pint_t funcStart = 0; 1766 pint_t funcEnd = 0; 1767 pint_t lsda = 0; 1768 pint_t personality = 0; 1769 uint32_t pageKind = _addressSpace.get32(secondLevelAddr); 1770 if (pageKind == UNWIND_SECOND_LEVEL_REGULAR) { 1771 // regular page 1772 UnwindSectionRegularPageHeader<A> pageHeader(_addressSpace, 1773 secondLevelAddr); 1774 UnwindSectionRegularArray<A> pageIndex( 1775 _addressSpace, secondLevelAddr + pageHeader.entryPageOffset()); 1776 // binary search looks for entry with e where index[e].offset <= pc < 1777 // index[e+1].offset 1778 if (log) 1779 fprintf(stderr, "\tbinary search for targetFunctionOffset=0x%08llX in " 1780 "regular page starting at secondLevelAddr=0x%llX\n", 1781 (uint64_t) targetFunctionOffset, (uint64_t) secondLevelAddr); 1782 low = 0; 1783 high = pageHeader.entryCount(); 1784 while (low < high) { 1785 uint32_t mid = (low + high) / 2; 1786 if (pageIndex.functionOffset(mid) <= targetFunctionOffset) { 1787 if (mid == (uint32_t)(pageHeader.entryCount() - 1)) { 1788 // at end of table 1789 low = mid; 1790 funcEnd = firstLevelNextPageFunctionOffset + sects.dso_base; 1791 break; 1792 } else if (pageIndex.functionOffset(mid + 1) > targetFunctionOffset) { 1793 // next is too big, so we found it 1794 low = mid; 1795 funcEnd = pageIndex.functionOffset(low + 1) + sects.dso_base; 1796 break; 1797 } else { 1798 low = mid + 1; 1799 } 1800 } else { 1801 high = mid; 1802 } 1803 } 1804 encoding = pageIndex.encoding(low); 1805 funcStart = pageIndex.functionOffset(low) + sects.dso_base; 1806 if (pc < funcStart) { 1807 if (log) 1808 fprintf( 1809 stderr, 1810 "\tpc not in table, pc=0x%llX, funcStart=0x%llX, funcEnd=0x%llX\n", 1811 (uint64_t) pc, (uint64_t) funcStart, (uint64_t) funcEnd); 1812 return false; 1813 } 1814 if (pc > funcEnd) { 1815 if (log) 1816 fprintf( 1817 stderr, 1818 "\tpc not in table, pc=0x%llX, funcStart=0x%llX, funcEnd=0x%llX\n", 1819 (uint64_t) pc, (uint64_t) funcStart, (uint64_t) funcEnd); 1820 return false; 1821 } 1822 } else if (pageKind == UNWIND_SECOND_LEVEL_COMPRESSED) { 1823 // compressed page 1824 UnwindSectionCompressedPageHeader<A> pageHeader(_addressSpace, 1825 secondLevelAddr); 1826 UnwindSectionCompressedArray<A> pageIndex( 1827 _addressSpace, secondLevelAddr + pageHeader.entryPageOffset()); 1828 const uint32_t targetFunctionPageOffset = 1829 (uint32_t)(targetFunctionOffset - firstLevelFunctionOffset); 1830 // binary search looks for entry with e where index[e].offset <= pc < 1831 // index[e+1].offset 1832 if (log) 1833 fprintf(stderr, "\tbinary search of compressed page starting at " 1834 "secondLevelAddr=0x%llX\n", 1835 (uint64_t) secondLevelAddr); 1836 low = 0; 1837 last = pageHeader.entryCount() - 1; 1838 high = pageHeader.entryCount(); 1839 while (low < high) { 1840 uint32_t mid = (low + high) / 2; 1841 if (pageIndex.functionOffset(mid) <= targetFunctionPageOffset) { 1842 if ((mid == last) || 1843 (pageIndex.functionOffset(mid + 1) > targetFunctionPageOffset)) { 1844 low = mid; 1845 break; 1846 } else { 1847 low = mid + 1; 1848 } 1849 } else { 1850 high = mid; 1851 } 1852 } 1853 funcStart = pageIndex.functionOffset(low) + firstLevelFunctionOffset 1854 + sects.dso_base; 1855 if (low < last) 1856 funcEnd = 1857 pageIndex.functionOffset(low + 1) + firstLevelFunctionOffset 1858 + sects.dso_base; 1859 else 1860 funcEnd = firstLevelNextPageFunctionOffset + sects.dso_base; 1861 if (pc < funcStart) { 1862 _LIBUNWIND_DEBUG_LOG("malformed __unwind_info, pc=0x%llX " 1863 "not in second level compressed unwind table. " 1864 "funcStart=0x%llX", 1865 (uint64_t) pc, (uint64_t) funcStart); 1866 return false; 1867 } 1868 if (pc > funcEnd) { 1869 _LIBUNWIND_DEBUG_LOG("malformed __unwind_info, pc=0x%llX " 1870 "not in second level compressed unwind table. " 1871 "funcEnd=0x%llX", 1872 (uint64_t) pc, (uint64_t) funcEnd); 1873 return false; 1874 } 1875 uint16_t encodingIndex = pageIndex.encodingIndex(low); 1876 if (encodingIndex < sectionHeader.commonEncodingsArrayCount()) { 1877 // encoding is in common table in section header 1878 encoding = _addressSpace.get32( 1879 sects.compact_unwind_section + 1880 sectionHeader.commonEncodingsArraySectionOffset() + 1881 encodingIndex * sizeof(uint32_t)); 1882 } else { 1883 // encoding is in page specific table 1884 uint16_t pageEncodingIndex = 1885 encodingIndex - (uint16_t)sectionHeader.commonEncodingsArrayCount(); 1886 encoding = _addressSpace.get32(secondLevelAddr + 1887 pageHeader.encodingsPageOffset() + 1888 pageEncodingIndex * sizeof(uint32_t)); 1889 } 1890 } else { 1891 _LIBUNWIND_DEBUG_LOG( 1892 "malformed __unwind_info at 0x%0llX bad second level page", 1893 (uint64_t)sects.compact_unwind_section); 1894 return false; 1895 } 1896 1897 // look up LSDA, if encoding says function has one 1898 if (encoding & UNWIND_HAS_LSDA) { 1899 UnwindSectionLsdaArray<A> lsdaIndex(_addressSpace, lsdaArrayStartAddr); 1900 uint32_t funcStartOffset = (uint32_t)(funcStart - sects.dso_base); 1901 low = 0; 1902 high = (uint32_t)(lsdaArrayEndAddr - lsdaArrayStartAddr) / 1903 sizeof(unwind_info_section_header_lsda_index_entry); 1904 // binary search looks for entry with exact match for functionOffset 1905 if (log) 1906 fprintf(stderr, 1907 "\tbinary search of lsda table for targetFunctionOffset=0x%08X\n", 1908 funcStartOffset); 1909 while (low < high) { 1910 uint32_t mid = (low + high) / 2; 1911 if (lsdaIndex.functionOffset(mid) == funcStartOffset) { 1912 lsda = lsdaIndex.lsdaOffset(mid) + sects.dso_base; 1913 break; 1914 } else if (lsdaIndex.functionOffset(mid) < funcStartOffset) { 1915 low = mid + 1; 1916 } else { 1917 high = mid; 1918 } 1919 } 1920 if (lsda == 0) { 1921 _LIBUNWIND_DEBUG_LOG("found encoding 0x%08X with HAS_LSDA bit set for " 1922 "pc=0x%0llX, but lsda table has no entry", 1923 encoding, (uint64_t) pc); 1924 return false; 1925 } 1926 } 1927 1928 // extract personality routine, if encoding says function has one 1929 uint32_t personalityIndex = (encoding & UNWIND_PERSONALITY_MASK) >> 1930 (__builtin_ctz(UNWIND_PERSONALITY_MASK)); 1931 if (personalityIndex != 0) { 1932 --personalityIndex; // change 1-based to zero-based index 1933 if (personalityIndex >= sectionHeader.personalityArrayCount()) { 1934 _LIBUNWIND_DEBUG_LOG("found encoding 0x%08X with personality index %d, " 1935 "but personality table has only %d entries", 1936 encoding, personalityIndex, 1937 sectionHeader.personalityArrayCount()); 1938 return false; 1939 } 1940 int32_t personalityDelta = (int32_t)_addressSpace.get32( 1941 sects.compact_unwind_section + 1942 sectionHeader.personalityArraySectionOffset() + 1943 personalityIndex * sizeof(uint32_t)); 1944 pint_t personalityPointer = sects.dso_base + (pint_t)personalityDelta; 1945 personality = _addressSpace.getP(personalityPointer); 1946 if (log) 1947 fprintf(stderr, "getInfoFromCompactEncodingSection(pc=0x%llX), " 1948 "personalityDelta=0x%08X, personality=0x%08llX\n", 1949 (uint64_t) pc, personalityDelta, (uint64_t) personality); 1950 } 1951 1952 if (log) 1953 fprintf(stderr, "getInfoFromCompactEncodingSection(pc=0x%llX), " 1954 "encoding=0x%08X, lsda=0x%08llX for funcStart=0x%llX\n", 1955 (uint64_t) pc, encoding, (uint64_t) lsda, (uint64_t) funcStart); 1956 _info.start_ip = funcStart; 1957 _info.end_ip = funcEnd; 1958 _info.lsda = lsda; 1959 _info.handler = personality; 1960 _info.gp = 0; 1961 _info.flags = 0; 1962 _info.format = encoding; 1963 _info.unwind_info = 0; 1964 _info.unwind_info_size = 0; 1965 _info.extra = sects.dso_base; 1966 return true; 1967 } 1968 #endif // defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND) 1969 1970 1971 #if defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) 1972 template <typename A, typename R> 1973 bool UnwindCursor<A, R>::getInfoFromSEH(pint_t pc) { 1974 pint_t base; 1975 RUNTIME_FUNCTION *unwindEntry = lookUpSEHUnwindInfo(pc, &base); 1976 if (!unwindEntry) { 1977 _LIBUNWIND_DEBUG_LOG("\tpc not in table, pc=0x%llX", (uint64_t) pc); 1978 return false; 1979 } 1980 _info.gp = 0; 1981 _info.flags = 0; 1982 _info.format = 0; 1983 _info.unwind_info_size = sizeof(RUNTIME_FUNCTION); 1984 _info.unwind_info = reinterpret_cast<unw_word_t>(unwindEntry); 1985 _info.extra = base; 1986 _info.start_ip = base + unwindEntry->BeginAddress; 1987 #ifdef _LIBUNWIND_TARGET_X86_64 1988 _info.end_ip = base + unwindEntry->EndAddress; 1989 // Only fill in the handler and LSDA if they're stale. 1990 if (pc != getLastPC()) { 1991 UNWIND_INFO *xdata = reinterpret_cast<UNWIND_INFO *>(base + unwindEntry->UnwindData); 1992 if (xdata->Flags & (UNW_FLAG_EHANDLER|UNW_FLAG_UHANDLER)) { 1993 // The personality is given in the UNWIND_INFO itself. The LSDA immediately 1994 // follows the UNWIND_INFO. (This follows how both Clang and MSVC emit 1995 // these structures.) 1996 // N.B. UNWIND_INFO structs are DWORD-aligned. 1997 uint32_t lastcode = (xdata->CountOfCodes + 1) & ~1; 1998 const uint32_t *handler = reinterpret_cast<uint32_t *>(&xdata->UnwindCodes[lastcode]); 1999 _info.lsda = reinterpret_cast<unw_word_t>(handler+1); 2000 _dispContext.HandlerData = reinterpret_cast<void *>(_info.lsda); 2001 _dispContext.LanguageHandler = 2002 reinterpret_cast<EXCEPTION_ROUTINE *>(base + *handler); 2003 if (*handler) { 2004 _info.handler = reinterpret_cast<unw_word_t>(__libunwind_seh_personality); 2005 } else 2006 _info.handler = 0; 2007 } else { 2008 _info.lsda = 0; 2009 _info.handler = 0; 2010 } 2011 } 2012 #endif 2013 setLastPC(pc); 2014 return true; 2015 } 2016 #endif 2017 2018 #if defined(_LIBUNWIND_SUPPORT_TBTAB_UNWIND) 2019 // Masks for traceback table field xtbtable. 2020 enum xTBTableMask : uint8_t { 2021 reservedBit = 0x02, // The traceback table was incorrectly generated if set 2022 // (see comments in function getInfoFromTBTable(). 2023 ehInfoBit = 0x08 // Exception handling info is present if set 2024 }; 2025 2026 enum frameType : unw_word_t { 2027 frameWithXLEHStateTable = 0, 2028 frameWithEHInfo = 1 2029 }; 2030 2031 extern "C" { 2032 typedef _Unwind_Reason_Code __xlcxx_personality_v0_t(int, _Unwind_Action, 2033 uint64_t, 2034 _Unwind_Exception *, 2035 struct _Unwind_Context *); 2036 __attribute__((__weak__)) __xlcxx_personality_v0_t __xlcxx_personality_v0; 2037 } 2038 2039 static __xlcxx_personality_v0_t *xlcPersonalityV0; 2040 static RWMutex xlcPersonalityV0InitLock; 2041 2042 template <typename A, typename R> 2043 bool UnwindCursor<A, R>::getInfoFromTBTable(pint_t pc, R ®isters) { 2044 uint32_t *p = reinterpret_cast<uint32_t *>(pc); 2045 2046 // Keep looking forward until a word of 0 is found. The traceback 2047 // table starts at the following word. 2048 while (*p) 2049 ++p; 2050 tbtable *TBTable = reinterpret_cast<tbtable *>(p + 1); 2051 2052 if (_LIBUNWIND_TRACING_UNWINDING) { 2053 char functionBuf[512]; 2054 const char *functionName = functionBuf; 2055 unw_word_t offset; 2056 if (!getFunctionName(functionBuf, sizeof(functionBuf), &offset)) { 2057 functionName = ".anonymous."; 2058 } 2059 _LIBUNWIND_TRACE_UNWINDING("%s: Look up traceback table of func=%s at %p", 2060 __func__, functionName, 2061 reinterpret_cast<void *>(TBTable)); 2062 } 2063 2064 // If the traceback table does not contain necessary info, bypass this frame. 2065 if (!TBTable->tb.has_tboff) 2066 return false; 2067 2068 // Structure tbtable_ext contains important data we are looking for. 2069 p = reinterpret_cast<uint32_t *>(&TBTable->tb_ext); 2070 2071 // Skip field parminfo if it exists. 2072 if (TBTable->tb.fixedparms || TBTable->tb.floatparms) 2073 ++p; 2074 2075 // p now points to tb_offset, the offset from start of function to TB table. 2076 unw_word_t start_ip = 2077 reinterpret_cast<unw_word_t>(TBTable) - *p - sizeof(uint32_t); 2078 unw_word_t end_ip = reinterpret_cast<unw_word_t>(TBTable); 2079 ++p; 2080 2081 _LIBUNWIND_TRACE_UNWINDING("start_ip=%p, end_ip=%p\n", 2082 reinterpret_cast<void *>(start_ip), 2083 reinterpret_cast<void *>(end_ip)); 2084 2085 // Skip field hand_mask if it exists. 2086 if (TBTable->tb.int_hndl) 2087 ++p; 2088 2089 unw_word_t lsda = 0; 2090 unw_word_t handler = 0; 2091 unw_word_t flags = frameType::frameWithXLEHStateTable; 2092 2093 if (TBTable->tb.lang == TB_CPLUSPLUS && TBTable->tb.has_ctl) { 2094 // State table info is available. The ctl_info field indicates the 2095 // number of CTL anchors. There should be only one entry for the C++ 2096 // state table. 2097 assert(*p == 1 && "libunwind: there must be only one ctl_info entry"); 2098 ++p; 2099 // p points to the offset of the state table into the stack. 2100 pint_t stateTableOffset = *p++; 2101 2102 int framePointerReg; 2103 2104 // Skip fields name_len and name if exist. 2105 if (TBTable->tb.name_present) { 2106 const uint16_t name_len = *(reinterpret_cast<uint16_t *>(p)); 2107 p = reinterpret_cast<uint32_t *>(reinterpret_cast<char *>(p) + name_len + 2108 sizeof(uint16_t)); 2109 } 2110 2111 if (TBTable->tb.uses_alloca) 2112 framePointerReg = *(reinterpret_cast<char *>(p)); 2113 else 2114 framePointerReg = 1; // default frame pointer == SP 2115 2116 _LIBUNWIND_TRACE_UNWINDING( 2117 "framePointerReg=%d, framePointer=%p, " 2118 "stateTableOffset=%#lx\n", 2119 framePointerReg, 2120 reinterpret_cast<void *>(_registers.getRegister(framePointerReg)), 2121 stateTableOffset); 2122 lsda = _registers.getRegister(framePointerReg) + stateTableOffset; 2123 2124 // Since the traceback table generated by the legacy XLC++ does not 2125 // provide the location of the personality for the state table, 2126 // function __xlcxx_personality_v0(), which is the personality for the state 2127 // table and is exported from libc++abi, is directly assigned as the 2128 // handler here. When a legacy XLC++ frame is encountered, the symbol 2129 // is resolved dynamically using dlopen() to avoid hard dependency from 2130 // libunwind on libc++abi. 2131 2132 // Resolve the function pointer to the state table personality if it has 2133 // not already. 2134 if (xlcPersonalityV0 == NULL) { 2135 xlcPersonalityV0InitLock.lock(); 2136 if (xlcPersonalityV0 == NULL) { 2137 // If libc++abi is statically linked in, symbol __xlcxx_personality_v0 2138 // has been resolved at the link time. 2139 xlcPersonalityV0 = &__xlcxx_personality_v0; 2140 if (xlcPersonalityV0 == NULL) { 2141 // libc++abi is dynamically linked. Resolve __xlcxx_personality_v0 2142 // using dlopen(). 2143 const char libcxxabi[] = "libc++abi.a(libc++abi.so.1)"; 2144 void *libHandle; 2145 // The AIX dlopen() sets errno to 0 when it is successful, which 2146 // clobbers the value of errno from the user code. This is an AIX 2147 // bug because according to POSIX it should not set errno to 0. To 2148 // workaround before AIX fixes the bug, errno is saved and restored. 2149 int saveErrno = errno; 2150 libHandle = dlopen(libcxxabi, RTLD_MEMBER | RTLD_NOW); 2151 if (libHandle == NULL) { 2152 _LIBUNWIND_TRACE_UNWINDING("dlopen() failed with errno=%d\n", 2153 errno); 2154 assert(0 && "dlopen() failed"); 2155 } 2156 xlcPersonalityV0 = reinterpret_cast<__xlcxx_personality_v0_t *>( 2157 dlsym(libHandle, "__xlcxx_personality_v0")); 2158 if (xlcPersonalityV0 == NULL) { 2159 _LIBUNWIND_TRACE_UNWINDING("dlsym() failed with errno=%d\n", errno); 2160 assert(0 && "dlsym() failed"); 2161 } 2162 dlclose(libHandle); 2163 errno = saveErrno; 2164 } 2165 } 2166 xlcPersonalityV0InitLock.unlock(); 2167 } 2168 handler = reinterpret_cast<unw_word_t>(xlcPersonalityV0); 2169 _LIBUNWIND_TRACE_UNWINDING("State table: LSDA=%p, Personality=%p\n", 2170 reinterpret_cast<void *>(lsda), 2171 reinterpret_cast<void *>(handler)); 2172 } else if (TBTable->tb.longtbtable) { 2173 // This frame has the traceback table extension. Possible cases are 2174 // 1) a C++ frame that has the 'eh_info' structure; 2) a C++ frame that 2175 // is not EH aware; or, 3) a frame of other languages. We need to figure out 2176 // if the traceback table extension contains the 'eh_info' structure. 2177 // 2178 // We also need to deal with the complexity arising from some XL compiler 2179 // versions use the wrong ordering of 'longtbtable' and 'has_vec' bits 2180 // where the 'longtbtable' bit is meant to be the 'has_vec' bit and vice 2181 // versa. For frames of code generated by those compilers, the 'longtbtable' 2182 // bit may be set but there isn't really a traceback table extension. 2183 // 2184 // In </usr/include/sys/debug.h>, there is the following definition of 2185 // 'struct tbtable_ext'. It is not really a structure but a dummy to 2186 // collect the description of optional parts of the traceback table. 2187 // 2188 // struct tbtable_ext { 2189 // ... 2190 // char alloca_reg; /* Register for alloca automatic storage */ 2191 // struct vec_ext vec_ext; /* Vector extension (if has_vec is set) */ 2192 // unsigned char xtbtable; /* More tbtable fields, if longtbtable is set*/ 2193 // }; 2194 // 2195 // Depending on how the 'has_vec'/'longtbtable' bit is interpreted, the data 2196 // following 'alloca_reg' can be treated either as 'struct vec_ext' or 2197 // 'unsigned char xtbtable'. 'xtbtable' bits are defined in 2198 // </usr/include/sys/debug.h> as flags. The 7th bit '0x02' is currently 2199 // unused and should not be set. 'struct vec_ext' is defined in 2200 // </usr/include/sys/debug.h> as follows: 2201 // 2202 // struct vec_ext { 2203 // unsigned vr_saved:6; /* Number of non-volatile vector regs saved 2204 // */ 2205 // /* first register saved is assumed to be */ 2206 // /* 32 - vr_saved */ 2207 // unsigned saves_vrsave:1; /* Set if vrsave is saved on the stack */ 2208 // unsigned has_varargs:1; 2209 // ... 2210 // }; 2211 // 2212 // Here, the 7th bit is used as 'saves_vrsave'. To determine whether it 2213 // is 'struct vec_ext' or 'xtbtable' that follows 'alloca_reg', 2214 // we checks if the 7th bit is set or not because 'xtbtable' should 2215 // never have the 7th bit set. The 7th bit of 'xtbtable' will be reserved 2216 // in the future to make sure the mitigation works. This mitigation 2217 // is not 100% bullet proof because 'struct vec_ext' may not always have 2218 // 'saves_vrsave' bit set. 2219 // 2220 // 'reservedBit' is defined in enum 'xTBTableMask' above as the mask for 2221 // checking the 7th bit. 2222 2223 // p points to field name len. 2224 uint8_t *charPtr = reinterpret_cast<uint8_t *>(p); 2225 2226 // Skip fields name_len and name if they exist. 2227 if (TBTable->tb.name_present) { 2228 const uint16_t name_len = *(reinterpret_cast<uint16_t *>(charPtr)); 2229 charPtr = charPtr + name_len + sizeof(uint16_t); 2230 } 2231 2232 // Skip field alloc_reg if it exists. 2233 if (TBTable->tb.uses_alloca) 2234 ++charPtr; 2235 2236 // Check traceback table bit has_vec. Skip struct vec_ext if it exists. 2237 if (TBTable->tb.has_vec) 2238 // Note struct vec_ext does exist at this point because whether the 2239 // ordering of longtbtable and has_vec bits is correct or not, both 2240 // are set. 2241 charPtr += sizeof(struct vec_ext); 2242 2243 // charPtr points to field 'xtbtable'. Check if the EH info is available. 2244 // Also check if the reserved bit of the extended traceback table field 2245 // 'xtbtable' is set. If it is, the traceback table was incorrectly 2246 // generated by an XL compiler that uses the wrong ordering of 'longtbtable' 2247 // and 'has_vec' bits and this is in fact 'struct vec_ext'. So skip the 2248 // frame. 2249 if ((*charPtr & xTBTableMask::ehInfoBit) && 2250 !(*charPtr & xTBTableMask::reservedBit)) { 2251 // Mark this frame has the new EH info. 2252 flags = frameType::frameWithEHInfo; 2253 2254 // eh_info is available. 2255 charPtr++; 2256 // The pointer is 4-byte aligned. 2257 if (reinterpret_cast<uintptr_t>(charPtr) % 4) 2258 charPtr += 4 - reinterpret_cast<uintptr_t>(charPtr) % 4; 2259 uintptr_t *ehInfo = 2260 reinterpret_cast<uintptr_t *>(*(reinterpret_cast<uintptr_t *>( 2261 registers.getRegister(2) + 2262 *(reinterpret_cast<uintptr_t *>(charPtr))))); 2263 2264 // ehInfo points to structure en_info. The first member is version. 2265 // Only version 0 is currently supported. 2266 assert(*(reinterpret_cast<uint32_t *>(ehInfo)) == 0 && 2267 "libunwind: ehInfo version other than 0 is not supported"); 2268 2269 // Increment ehInfo to point to member lsda. 2270 ++ehInfo; 2271 lsda = *ehInfo++; 2272 2273 // enInfo now points to member personality. 2274 handler = *ehInfo; 2275 2276 _LIBUNWIND_TRACE_UNWINDING("Range table: LSDA=%#lx, Personality=%#lx\n", 2277 lsda, handler); 2278 } 2279 } 2280 2281 _info.start_ip = start_ip; 2282 _info.end_ip = end_ip; 2283 _info.lsda = lsda; 2284 _info.handler = handler; 2285 _info.gp = 0; 2286 _info.flags = flags; 2287 _info.format = 0; 2288 _info.unwind_info = reinterpret_cast<unw_word_t>(TBTable); 2289 _info.unwind_info_size = 0; 2290 _info.extra = registers.getRegister(2); 2291 2292 return true; 2293 } 2294 2295 // Step back up the stack following the frame back link. 2296 template <typename A, typename R> 2297 int UnwindCursor<A, R>::stepWithTBTable(pint_t pc, tbtable *TBTable, 2298 R ®isters, bool &isSignalFrame) { 2299 if (_LIBUNWIND_TRACING_UNWINDING) { 2300 char functionBuf[512]; 2301 const char *functionName = functionBuf; 2302 unw_word_t offset; 2303 if (!getFunctionName(functionBuf, sizeof(functionBuf), &offset)) { 2304 functionName = ".anonymous."; 2305 } 2306 _LIBUNWIND_TRACE_UNWINDING( 2307 "%s: Look up traceback table of func=%s at %p, pc=%p, " 2308 "SP=%p, saves_lr=%d, stores_bc=%d", 2309 __func__, functionName, reinterpret_cast<void *>(TBTable), 2310 reinterpret_cast<void *>(pc), 2311 reinterpret_cast<void *>(registers.getSP()), TBTable->tb.saves_lr, 2312 TBTable->tb.stores_bc); 2313 } 2314 2315 #if defined(__powerpc64__) 2316 // Instruction to reload TOC register "ld r2,40(r1)" 2317 const uint32_t loadTOCRegInst = 0xe8410028; 2318 const int32_t unwPPCF0Index = UNW_PPC64_F0; 2319 const int32_t unwPPCV0Index = UNW_PPC64_V0; 2320 #else 2321 // Instruction to reload TOC register "lwz r2,20(r1)" 2322 const uint32_t loadTOCRegInst = 0x80410014; 2323 const int32_t unwPPCF0Index = UNW_PPC_F0; 2324 const int32_t unwPPCV0Index = UNW_PPC_V0; 2325 #endif 2326 2327 // lastStack points to the stack frame of the next routine up. 2328 pint_t curStack = static_cast<pint_t>(registers.getSP()); 2329 pint_t lastStack = *reinterpret_cast<pint_t *>(curStack); 2330 2331 if (lastStack == 0) 2332 return UNW_STEP_END; 2333 2334 R newRegisters = registers; 2335 2336 // If backchain is not stored, use the current stack frame. 2337 if (!TBTable->tb.stores_bc) 2338 lastStack = curStack; 2339 2340 // Return address is the address after call site instruction. 2341 pint_t returnAddress; 2342 2343 if (isSignalFrame) { 2344 _LIBUNWIND_TRACE_UNWINDING("Possible signal handler frame: lastStack=%p", 2345 reinterpret_cast<void *>(lastStack)); 2346 2347 sigcontext *sigContext = reinterpret_cast<sigcontext *>( 2348 reinterpret_cast<char *>(lastStack) + STKMINALIGN); 2349 returnAddress = sigContext->sc_jmpbuf.jmp_context.iar; 2350 2351 bool useSTKMIN = false; 2352 if (returnAddress < 0x10000000) { 2353 // Try again using STKMIN. 2354 sigContext = reinterpret_cast<sigcontext *>( 2355 reinterpret_cast<char *>(lastStack) + STKMIN); 2356 returnAddress = sigContext->sc_jmpbuf.jmp_context.iar; 2357 if (returnAddress < 0x10000000) { 2358 _LIBUNWIND_TRACE_UNWINDING("Bad returnAddress=%p from sigcontext=%p", 2359 reinterpret_cast<void *>(returnAddress), 2360 reinterpret_cast<void *>(sigContext)); 2361 return UNW_EBADFRAME; 2362 } 2363 useSTKMIN = true; 2364 } 2365 _LIBUNWIND_TRACE_UNWINDING("Returning from a signal handler %s: " 2366 "sigContext=%p, returnAddress=%p. " 2367 "Seems to be a valid address", 2368 useSTKMIN ? "STKMIN" : "STKMINALIGN", 2369 reinterpret_cast<void *>(sigContext), 2370 reinterpret_cast<void *>(returnAddress)); 2371 2372 // Restore the condition register from sigcontext. 2373 newRegisters.setCR(sigContext->sc_jmpbuf.jmp_context.cr); 2374 2375 // Save the LR in sigcontext for stepping up when the function that 2376 // raised the signal is a leaf function. This LR has the return address 2377 // to the caller of the leaf function. 2378 newRegisters.setLR(sigContext->sc_jmpbuf.jmp_context.lr); 2379 _LIBUNWIND_TRACE_UNWINDING( 2380 "Save LR=%p from sigcontext", 2381 reinterpret_cast<void *>(sigContext->sc_jmpbuf.jmp_context.lr)); 2382 2383 // Restore GPRs from sigcontext. 2384 for (int i = 0; i < 32; ++i) 2385 newRegisters.setRegister(i, sigContext->sc_jmpbuf.jmp_context.gpr[i]); 2386 2387 // Restore FPRs from sigcontext. 2388 for (int i = 0; i < 32; ++i) 2389 newRegisters.setFloatRegister(i + unwPPCF0Index, 2390 sigContext->sc_jmpbuf.jmp_context.fpr[i]); 2391 2392 // Restore vector registers if there is an associated extended context 2393 // structure. 2394 if (sigContext->sc_jmpbuf.jmp_context.msr & __EXTCTX) { 2395 ucontext_t *uContext = reinterpret_cast<ucontext_t *>(sigContext); 2396 if (uContext->__extctx->__extctx_magic == __EXTCTX_MAGIC) { 2397 for (int i = 0; i < 32; ++i) 2398 newRegisters.setVectorRegister( 2399 i + unwPPCV0Index, *(reinterpret_cast<v128 *>( 2400 &(uContext->__extctx->__vmx.__vr[i])))); 2401 } 2402 } 2403 } else { 2404 // Step up a normal frame. 2405 2406 if (!TBTable->tb.saves_lr && registers.getLR()) { 2407 // This case should only occur if we were called from a signal handler 2408 // and the signal occurred in a function that doesn't save the LR. 2409 returnAddress = static_cast<pint_t>(registers.getLR()); 2410 _LIBUNWIND_TRACE_UNWINDING("Use saved LR=%p", 2411 reinterpret_cast<void *>(returnAddress)); 2412 } else { 2413 // Otherwise, use the LR value in the stack link area. 2414 returnAddress = reinterpret_cast<pint_t *>(lastStack)[2]; 2415 } 2416 2417 // Reset LR in the current context. 2418 newRegisters.setLR(static_cast<uintptr_t>(NULL)); 2419 2420 _LIBUNWIND_TRACE_UNWINDING( 2421 "Extract info from lastStack=%p, returnAddress=%p", 2422 reinterpret_cast<void *>(lastStack), 2423 reinterpret_cast<void *>(returnAddress)); 2424 _LIBUNWIND_TRACE_UNWINDING("fpr_regs=%d, gpr_regs=%d, saves_cr=%d", 2425 TBTable->tb.fpr_saved, TBTable->tb.gpr_saved, 2426 TBTable->tb.saves_cr); 2427 2428 // Restore FP registers. 2429 char *ptrToRegs = reinterpret_cast<char *>(lastStack); 2430 double *FPRegs = reinterpret_cast<double *>( 2431 ptrToRegs - (TBTable->tb.fpr_saved * sizeof(double))); 2432 for (int i = 0; i < TBTable->tb.fpr_saved; ++i) 2433 newRegisters.setFloatRegister( 2434 32 - TBTable->tb.fpr_saved + i + unwPPCF0Index, FPRegs[i]); 2435 2436 // Restore GP registers. 2437 ptrToRegs = reinterpret_cast<char *>(FPRegs); 2438 uintptr_t *GPRegs = reinterpret_cast<uintptr_t *>( 2439 ptrToRegs - (TBTable->tb.gpr_saved * sizeof(uintptr_t))); 2440 for (int i = 0; i < TBTable->tb.gpr_saved; ++i) 2441 newRegisters.setRegister(32 - TBTable->tb.gpr_saved + i, GPRegs[i]); 2442 2443 // Restore Vector registers. 2444 ptrToRegs = reinterpret_cast<char *>(GPRegs); 2445 2446 // Restore vector registers only if this is a Clang frame. Also 2447 // check if traceback table bit has_vec is set. If it is, structure 2448 // vec_ext is available. 2449 if (_info.flags == frameType::frameWithEHInfo && TBTable->tb.has_vec) { 2450 2451 // Get to the vec_ext structure to check if vector registers are saved. 2452 uint32_t *p = reinterpret_cast<uint32_t *>(&TBTable->tb_ext); 2453 2454 // Skip field parminfo if exists. 2455 if (TBTable->tb.fixedparms || TBTable->tb.floatparms) 2456 ++p; 2457 2458 // Skip field tb_offset if exists. 2459 if (TBTable->tb.has_tboff) 2460 ++p; 2461 2462 // Skip field hand_mask if exists. 2463 if (TBTable->tb.int_hndl) 2464 ++p; 2465 2466 // Skip fields ctl_info and ctl_info_disp if exist. 2467 if (TBTable->tb.has_ctl) { 2468 // Skip field ctl_info. 2469 ++p; 2470 // Skip field ctl_info_disp. 2471 ++p; 2472 } 2473 2474 // Skip fields name_len and name if exist. 2475 // p is supposed to point to field name_len now. 2476 uint8_t *charPtr = reinterpret_cast<uint8_t *>(p); 2477 if (TBTable->tb.name_present) { 2478 const uint16_t name_len = *(reinterpret_cast<uint16_t *>(charPtr)); 2479 charPtr = charPtr + name_len + sizeof(uint16_t); 2480 } 2481 2482 // Skip field alloc_reg if it exists. 2483 if (TBTable->tb.uses_alloca) 2484 ++charPtr; 2485 2486 struct vec_ext *vec_ext = reinterpret_cast<struct vec_ext *>(charPtr); 2487 2488 _LIBUNWIND_TRACE_UNWINDING("vr_saved=%d", vec_ext->vr_saved); 2489 2490 // Restore vector register(s) if saved on the stack. 2491 if (vec_ext->vr_saved) { 2492 // Saved vector registers are 16-byte aligned. 2493 if (reinterpret_cast<uintptr_t>(ptrToRegs) % 16) 2494 ptrToRegs -= reinterpret_cast<uintptr_t>(ptrToRegs) % 16; 2495 v128 *VecRegs = reinterpret_cast<v128 *>(ptrToRegs - vec_ext->vr_saved * 2496 sizeof(v128)); 2497 for (int i = 0; i < vec_ext->vr_saved; ++i) { 2498 newRegisters.setVectorRegister( 2499 32 - vec_ext->vr_saved + i + unwPPCV0Index, VecRegs[i]); 2500 } 2501 } 2502 } 2503 if (TBTable->tb.saves_cr) { 2504 // Get the saved condition register. The condition register is only 2505 // a single word. 2506 newRegisters.setCR( 2507 *(reinterpret_cast<uint32_t *>(lastStack + sizeof(uintptr_t)))); 2508 } 2509 2510 // Restore the SP. 2511 newRegisters.setSP(lastStack); 2512 2513 // The first instruction after return. 2514 uint32_t firstInstruction = *(reinterpret_cast<uint32_t *>(returnAddress)); 2515 2516 // Do we need to set the TOC register? 2517 _LIBUNWIND_TRACE_UNWINDING( 2518 "Current gpr2=%p", 2519 reinterpret_cast<void *>(newRegisters.getRegister(2))); 2520 if (firstInstruction == loadTOCRegInst) { 2521 _LIBUNWIND_TRACE_UNWINDING( 2522 "Set gpr2=%p from frame", 2523 reinterpret_cast<void *>(reinterpret_cast<pint_t *>(lastStack)[5])); 2524 newRegisters.setRegister(2, reinterpret_cast<pint_t *>(lastStack)[5]); 2525 } 2526 } 2527 _LIBUNWIND_TRACE_UNWINDING("lastStack=%p, returnAddress=%p, pc=%p\n", 2528 reinterpret_cast<void *>(lastStack), 2529 reinterpret_cast<void *>(returnAddress), 2530 reinterpret_cast<void *>(pc)); 2531 2532 // The return address is the address after call site instruction, so 2533 // setting IP to that simulates a return. 2534 newRegisters.setIP(reinterpret_cast<uintptr_t>(returnAddress)); 2535 2536 // Simulate the step by replacing the register set with the new ones. 2537 registers = newRegisters; 2538 2539 // Check if the next frame is a signal frame. 2540 pint_t nextStack = *(reinterpret_cast<pint_t *>(registers.getSP())); 2541 2542 // Return address is the address after call site instruction. 2543 pint_t nextReturnAddress = reinterpret_cast<pint_t *>(nextStack)[2]; 2544 2545 if (nextReturnAddress > 0x01 && nextReturnAddress < 0x10000) { 2546 _LIBUNWIND_TRACE_UNWINDING("The next is a signal handler frame: " 2547 "nextStack=%p, next return address=%p\n", 2548 reinterpret_cast<void *>(nextStack), 2549 reinterpret_cast<void *>(nextReturnAddress)); 2550 isSignalFrame = true; 2551 } else { 2552 isSignalFrame = false; 2553 } 2554 return UNW_STEP_SUCCESS; 2555 } 2556 #endif // defined(_LIBUNWIND_SUPPORT_TBTAB_UNWIND) 2557 2558 template <typename A, typename R> 2559 void UnwindCursor<A, R>::setInfoBasedOnIPRegister(bool isReturnAddress) { 2560 #if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) 2561 _isSigReturn = false; 2562 #endif 2563 2564 pint_t pc = static_cast<pint_t>(this->getReg(UNW_REG_IP)); 2565 #if defined(_LIBUNWIND_ARM_EHABI) 2566 // Remove the thumb bit so the IP represents the actual instruction address. 2567 // This matches the behaviour of _Unwind_GetIP on arm. 2568 pc &= (pint_t)~0x1; 2569 #endif 2570 2571 // Exit early if at the top of the stack. 2572 if (pc == 0) { 2573 _unwindInfoMissing = true; 2574 return; 2575 } 2576 2577 // If the last line of a function is a "throw" the compiler sometimes 2578 // emits no instructions after the call to __cxa_throw. This means 2579 // the return address is actually the start of the next function. 2580 // To disambiguate this, back up the pc when we know it is a return 2581 // address. 2582 if (isReturnAddress) 2583 #if defined(_AIX) 2584 // PC needs to be a 4-byte aligned address to be able to look for a 2585 // word of 0 that indicates the start of the traceback table at the end 2586 // of a function on AIX. 2587 pc -= 4; 2588 #else 2589 --pc; 2590 #endif 2591 2592 #if !(defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) && defined(_WIN32)) 2593 // In case of this is frame of signal handler, the IP saved in the signal 2594 // handler points to first non-executed instruction, while FDE/CIE expects IP 2595 // to be after the first non-executed instruction. 2596 if (_isSignalFrame) 2597 ++pc; 2598 #endif 2599 2600 // Ask address space object to find unwind sections for this pc. 2601 UnwindInfoSections sects; 2602 if (_addressSpace.findUnwindSections(pc, sects)) { 2603 #if defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND) 2604 // If there is a compact unwind encoding table, look there first. 2605 if (sects.compact_unwind_section != 0) { 2606 if (this->getInfoFromCompactEncodingSection(pc, sects)) { 2607 #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 2608 // Found info in table, done unless encoding says to use dwarf. 2609 uint32_t dwarfOffset; 2610 if ((sects.dwarf_section != 0) && compactSaysUseDwarf(&dwarfOffset)) { 2611 if (this->getInfoFromDwarfSection(pc, sects, dwarfOffset)) { 2612 // found info in dwarf, done 2613 return; 2614 } 2615 } 2616 #endif 2617 // If unwind table has entry, but entry says there is no unwind info, 2618 // record that we have no unwind info. 2619 if (_info.format == 0) 2620 _unwindInfoMissing = true; 2621 return; 2622 } 2623 } 2624 #endif // defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND) 2625 2626 #if defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) 2627 // If there is SEH unwind info, look there next. 2628 if (this->getInfoFromSEH(pc)) 2629 return; 2630 #endif 2631 2632 #if defined(_LIBUNWIND_SUPPORT_TBTAB_UNWIND) 2633 // If there is unwind info in the traceback table, look there next. 2634 if (this->getInfoFromTBTable(pc, _registers)) 2635 return; 2636 #endif 2637 2638 #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 2639 // If there is dwarf unwind info, look there next. 2640 if (sects.dwarf_section != 0) { 2641 if (this->getInfoFromDwarfSection(pc, sects)) { 2642 // found info in dwarf, done 2643 return; 2644 } 2645 } 2646 #endif 2647 2648 #if defined(_LIBUNWIND_ARM_EHABI) 2649 // If there is ARM EHABI unwind info, look there next. 2650 if (sects.arm_section != 0 && this->getInfoFromEHABISection(pc, sects)) 2651 return; 2652 #endif 2653 } 2654 2655 #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 2656 // There is no static unwind info for this pc. Look to see if an FDE was 2657 // dynamically registered for it. 2658 pint_t cachedFDE = DwarfFDECache<A>::findFDE(DwarfFDECache<A>::kSearchAll, 2659 pc); 2660 if (cachedFDE != 0) { 2661 typename CFI_Parser<A>::FDE_Info fdeInfo; 2662 typename CFI_Parser<A>::CIE_Info cieInfo; 2663 if (!CFI_Parser<A>::decodeFDE(_addressSpace, cachedFDE, &fdeInfo, &cieInfo)) 2664 if (getInfoFromFdeCie(fdeInfo, cieInfo, pc, 0)) 2665 return; 2666 } 2667 2668 // Lastly, ask AddressSpace object about platform specific ways to locate 2669 // other FDEs. 2670 pint_t fde; 2671 if (_addressSpace.findOtherFDE(pc, fde)) { 2672 typename CFI_Parser<A>::FDE_Info fdeInfo; 2673 typename CFI_Parser<A>::CIE_Info cieInfo; 2674 if (!CFI_Parser<A>::decodeFDE(_addressSpace, fde, &fdeInfo, &cieInfo)) { 2675 // Double check this FDE is for a function that includes the pc. 2676 if ((fdeInfo.pcStart <= pc) && (pc < fdeInfo.pcEnd)) 2677 if (getInfoFromFdeCie(fdeInfo, cieInfo, pc, 0)) 2678 return; 2679 } 2680 } 2681 #endif // #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 2682 2683 #if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) 2684 if (setInfoForSigReturn()) 2685 return; 2686 #endif 2687 2688 // no unwind info, flag that we can't reliably unwind 2689 _unwindInfoMissing = true; 2690 } 2691 2692 #if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) && \ 2693 defined(_LIBUNWIND_TARGET_AARCH64) 2694 template <typename A, typename R> 2695 bool UnwindCursor<A, R>::setInfoForSigReturn(Registers_arm64 &) { 2696 // Look for the sigreturn trampoline. The trampoline's body is two 2697 // specific instructions (see below). Typically the trampoline comes from the 2698 // vDSO[1] (i.e. the __kernel_rt_sigreturn function). A libc might provide its 2699 // own restorer function, though, or user-mode QEMU might write a trampoline 2700 // onto the stack. 2701 // 2702 // This special code path is a fallback that is only used if the trampoline 2703 // lacks proper (e.g. DWARF) unwind info. On AArch64, a new DWARF register 2704 // constant for the PC needs to be defined before DWARF can handle a signal 2705 // trampoline. This code may segfault if the target PC is unreadable, e.g.: 2706 // - The PC points at a function compiled without unwind info, and which is 2707 // part of an execute-only mapping (e.g. using -Wl,--execute-only). 2708 // - The PC is invalid and happens to point to unreadable or unmapped memory. 2709 // 2710 // [1] https://github.com/torvalds/linux/blob/master/arch/arm64/kernel/vdso/sigreturn.S 2711 const pint_t pc = static_cast<pint_t>(this->getReg(UNW_REG_IP)); 2712 // The PC might contain an invalid address if the unwind info is bad, so 2713 // directly accessing it could cause a SIGSEGV. 2714 if (!isReadableAddr(pc)) 2715 return false; 2716 auto *instructions = reinterpret_cast<const uint32_t *>(pc); 2717 // Look for instructions: mov x8, #0x8b; svc #0x0 2718 if (instructions[0] != 0xd2801168 || instructions[1] != 0xd4000001) 2719 return false; 2720 2721 _info = {}; 2722 _info.start_ip = pc; 2723 _info.end_ip = pc + 4; 2724 _isSigReturn = true; 2725 return true; 2726 } 2727 2728 template <typename A, typename R> 2729 int UnwindCursor<A, R>::stepThroughSigReturn(Registers_arm64 &) { 2730 // In the signal trampoline frame, sp points to an rt_sigframe[1], which is: 2731 // - 128-byte siginfo struct 2732 // - ucontext struct: 2733 // - 8-byte long (uc_flags) 2734 // - 8-byte pointer (uc_link) 2735 // - 24-byte stack_t 2736 // - 128-byte signal set 2737 // - 8 bytes of padding because sigcontext has 16-byte alignment 2738 // - sigcontext/mcontext_t 2739 // [1] https://github.com/torvalds/linux/blob/master/arch/arm64/kernel/signal.c 2740 const pint_t kOffsetSpToSigcontext = (128 + 8 + 8 + 24 + 128 + 8); // 304 2741 2742 // Offsets from sigcontext to each register. 2743 const pint_t kOffsetGprs = 8; // offset to "__u64 regs[31]" field 2744 const pint_t kOffsetSp = 256; // offset to "__u64 sp" field 2745 const pint_t kOffsetPc = 264; // offset to "__u64 pc" field 2746 2747 pint_t sigctx = _registers.getSP() + kOffsetSpToSigcontext; 2748 2749 for (int i = 0; i <= 30; ++i) { 2750 uint64_t value = _addressSpace.get64(sigctx + kOffsetGprs + 2751 static_cast<pint_t>(i * 8)); 2752 _registers.setRegister(UNW_AARCH64_X0 + i, value); 2753 } 2754 _registers.setSP(_addressSpace.get64(sigctx + kOffsetSp)); 2755 _registers.setIP(_addressSpace.get64(sigctx + kOffsetPc)); 2756 _isSignalFrame = true; 2757 return UNW_STEP_SUCCESS; 2758 } 2759 #endif // defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) && 2760 // defined(_LIBUNWIND_TARGET_AARCH64) 2761 2762 #if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) && \ 2763 defined(_LIBUNWIND_TARGET_RISCV) 2764 template <typename A, typename R> 2765 bool UnwindCursor<A, R>::setInfoForSigReturn(Registers_riscv &) { 2766 const pint_t pc = static_cast<pint_t>(getReg(UNW_REG_IP)); 2767 // The PC might contain an invalid address if the unwind info is bad, so 2768 // directly accessing it could cause a SIGSEGV. 2769 if (!isReadableAddr(pc)) 2770 return false; 2771 const auto *instructions = reinterpret_cast<const uint32_t *>(pc); 2772 // Look for the two instructions used in the sigreturn trampoline 2773 // __vdso_rt_sigreturn: 2774 // 2775 // 0x08b00893 li a7,0x8b 2776 // 0x00000073 ecall 2777 if (instructions[0] != 0x08b00893 || instructions[1] != 0x00000073) 2778 return false; 2779 2780 _info = {}; 2781 _info.start_ip = pc; 2782 _info.end_ip = pc + 4; 2783 _isSigReturn = true; 2784 return true; 2785 } 2786 2787 template <typename A, typename R> 2788 int UnwindCursor<A, R>::stepThroughSigReturn(Registers_riscv &) { 2789 // In the signal trampoline frame, sp points to an rt_sigframe[1], which is: 2790 // - 128-byte siginfo struct 2791 // - ucontext_t struct: 2792 // - 8-byte long (__uc_flags) 2793 // - 8-byte pointer (*uc_link) 2794 // - 24-byte uc_stack 2795 // - 8-byte uc_sigmask 2796 // - 120-byte of padding to allow sigset_t to be expanded in the future 2797 // - 8 bytes of padding because sigcontext has 16-byte alignment 2798 // - struct sigcontext uc_mcontext 2799 // [1] 2800 // https://github.com/torvalds/linux/blob/master/arch/riscv/kernel/signal.c 2801 const pint_t kOffsetSpToSigcontext = 128 + 8 + 8 + 24 + 8 + 128; 2802 2803 const pint_t sigctx = _registers.getSP() + kOffsetSpToSigcontext; 2804 _registers.setIP(_addressSpace.get64(sigctx)); 2805 for (int i = UNW_RISCV_X1; i <= UNW_RISCV_X31; ++i) { 2806 uint64_t value = _addressSpace.get64(sigctx + static_cast<pint_t>(i * 8)); 2807 _registers.setRegister(i, value); 2808 } 2809 _isSignalFrame = true; 2810 return UNW_STEP_SUCCESS; 2811 } 2812 #endif // defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) && 2813 // defined(_LIBUNWIND_TARGET_RISCV) 2814 2815 #if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) && \ 2816 defined(_LIBUNWIND_TARGET_S390X) 2817 template <typename A, typename R> 2818 bool UnwindCursor<A, R>::setInfoForSigReturn(Registers_s390x &) { 2819 // Look for the sigreturn trampoline. The trampoline's body is a 2820 // specific instruction (see below). Typically the trampoline comes from the 2821 // vDSO (i.e. the __kernel_[rt_]sigreturn function). A libc might provide its 2822 // own restorer function, though, or user-mode QEMU might write a trampoline 2823 // onto the stack. 2824 const pint_t pc = static_cast<pint_t>(this->getReg(UNW_REG_IP)); 2825 // The PC might contain an invalid address if the unwind info is bad, so 2826 // directly accessing it could cause a SIGSEGV. 2827 if (!isReadableAddr(pc)) 2828 return false; 2829 const auto inst = *reinterpret_cast<const uint16_t *>(pc); 2830 if (inst == 0x0a77 || inst == 0x0aad) { 2831 _info = {}; 2832 _info.start_ip = pc; 2833 _info.end_ip = pc + 2; 2834 _isSigReturn = true; 2835 return true; 2836 } 2837 return false; 2838 } 2839 2840 template <typename A, typename R> 2841 int UnwindCursor<A, R>::stepThroughSigReturn(Registers_s390x &) { 2842 // Determine current SP. 2843 const pint_t sp = static_cast<pint_t>(this->getReg(UNW_REG_SP)); 2844 // According to the s390x ABI, the CFA is at (incoming) SP + 160. 2845 const pint_t cfa = sp + 160; 2846 2847 // Determine current PC and instruction there (this must be either 2848 // a "svc __NR_sigreturn" or "svc __NR_rt_sigreturn"). 2849 const pint_t pc = static_cast<pint_t>(this->getReg(UNW_REG_IP)); 2850 const uint16_t inst = _addressSpace.get16(pc); 2851 2852 // Find the addresses of the signo and sigcontext in the frame. 2853 pint_t pSigctx = 0; 2854 pint_t pSigno = 0; 2855 2856 // "svc __NR_sigreturn" uses a non-RT signal trampoline frame. 2857 if (inst == 0x0a77) { 2858 // Layout of a non-RT signal trampoline frame, starting at the CFA: 2859 // - 8-byte signal mask 2860 // - 8-byte pointer to sigcontext, followed by signo 2861 // - 4-byte signo 2862 pSigctx = _addressSpace.get64(cfa + 8); 2863 pSigno = pSigctx + 344; 2864 } 2865 2866 // "svc __NR_rt_sigreturn" uses a RT signal trampoline frame. 2867 if (inst == 0x0aad) { 2868 // Layout of a RT signal trampoline frame, starting at the CFA: 2869 // - 8-byte retcode (+ alignment) 2870 // - 128-byte siginfo struct (starts with signo) 2871 // - ucontext struct: 2872 // - 8-byte long (uc_flags) 2873 // - 8-byte pointer (uc_link) 2874 // - 24-byte stack_t 2875 // - 8 bytes of padding because sigcontext has 16-byte alignment 2876 // - sigcontext/mcontext_t 2877 pSigctx = cfa + 8 + 128 + 8 + 8 + 24 + 8; 2878 pSigno = cfa + 8; 2879 } 2880 2881 assert(pSigctx != 0); 2882 assert(pSigno != 0); 2883 2884 // Offsets from sigcontext to each register. 2885 const pint_t kOffsetPc = 8; 2886 const pint_t kOffsetGprs = 16; 2887 const pint_t kOffsetFprs = 216; 2888 2889 // Restore all registers. 2890 for (int i = 0; i < 16; ++i) { 2891 uint64_t value = _addressSpace.get64(pSigctx + kOffsetGprs + 2892 static_cast<pint_t>(i * 8)); 2893 _registers.setRegister(UNW_S390X_R0 + i, value); 2894 } 2895 for (int i = 0; i < 16; ++i) { 2896 static const int fpr[16] = { 2897 UNW_S390X_F0, UNW_S390X_F1, UNW_S390X_F2, UNW_S390X_F3, 2898 UNW_S390X_F4, UNW_S390X_F5, UNW_S390X_F6, UNW_S390X_F7, 2899 UNW_S390X_F8, UNW_S390X_F9, UNW_S390X_F10, UNW_S390X_F11, 2900 UNW_S390X_F12, UNW_S390X_F13, UNW_S390X_F14, UNW_S390X_F15 2901 }; 2902 double value = _addressSpace.getDouble(pSigctx + kOffsetFprs + 2903 static_cast<pint_t>(i * 8)); 2904 _registers.setFloatRegister(fpr[i], value); 2905 } 2906 _registers.setIP(_addressSpace.get64(pSigctx + kOffsetPc)); 2907 2908 // SIGILL, SIGFPE and SIGTRAP are delivered with psw_addr 2909 // after the faulting instruction rather than before it. 2910 // Do not set _isSignalFrame in that case. 2911 uint32_t signo = _addressSpace.get32(pSigno); 2912 _isSignalFrame = (signo != 4 && signo != 5 && signo != 8); 2913 2914 return UNW_STEP_SUCCESS; 2915 } 2916 #endif // defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) && 2917 // defined(_LIBUNWIND_TARGET_S390X) 2918 2919 template <typename A, typename R> int UnwindCursor<A, R>::step(bool stage2) { 2920 (void)stage2; 2921 // Bottom of stack is defined is when unwind info cannot be found. 2922 if (_unwindInfoMissing) 2923 return UNW_STEP_END; 2924 2925 // Use unwinding info to modify register set as if function returned. 2926 int result; 2927 #if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) 2928 if (_isSigReturn) { 2929 result = this->stepThroughSigReturn(); 2930 } else 2931 #endif 2932 { 2933 #if defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND) 2934 result = this->stepWithCompactEncoding(stage2); 2935 #elif defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) 2936 result = this->stepWithSEHData(); 2937 #elif defined(_LIBUNWIND_SUPPORT_TBTAB_UNWIND) 2938 result = this->stepWithTBTableData(); 2939 #elif defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 2940 result = this->stepWithDwarfFDE(stage2); 2941 #elif defined(_LIBUNWIND_ARM_EHABI) 2942 result = this->stepWithEHABI(); 2943 #else 2944 #error Need _LIBUNWIND_SUPPORT_COMPACT_UNWIND or \ 2945 _LIBUNWIND_SUPPORT_SEH_UNWIND or \ 2946 _LIBUNWIND_SUPPORT_DWARF_UNWIND or \ 2947 _LIBUNWIND_ARM_EHABI 2948 #endif 2949 } 2950 2951 // update info based on new PC 2952 if (result == UNW_STEP_SUCCESS) { 2953 this->setInfoBasedOnIPRegister(true); 2954 if (_unwindInfoMissing) 2955 return UNW_STEP_END; 2956 } 2957 2958 return result; 2959 } 2960 2961 template <typename A, typename R> 2962 void UnwindCursor<A, R>::getInfo(unw_proc_info_t *info) { 2963 if (_unwindInfoMissing) 2964 memset(info, 0, sizeof(*info)); 2965 else 2966 *info = _info; 2967 } 2968 2969 template <typename A, typename R> 2970 bool UnwindCursor<A, R>::getFunctionName(char *buf, size_t bufLen, 2971 unw_word_t *offset) { 2972 return _addressSpace.findFunctionName((pint_t)this->getReg(UNW_REG_IP), 2973 buf, bufLen, offset); 2974 } 2975 2976 #if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) 2977 template <typename A, typename R> 2978 bool UnwindCursor<A, R>::isReadableAddr(const pint_t addr) const { 2979 // We use SYS_rt_sigprocmask, inspired by Abseil's AddressIsReadable. 2980 2981 const auto sigsetAddr = reinterpret_cast<sigset_t *>(addr); 2982 // We have to check that addr is nullptr because sigprocmask allows that 2983 // as an argument without failure. 2984 if (!sigsetAddr) 2985 return false; 2986 const auto saveErrno = errno; 2987 // We MUST use a raw syscall here, as wrappers may try to access 2988 // sigsetAddr which may cause a SIGSEGV. A raw syscall however is 2989 // safe. Additionally, we need to pass the kernel_sigset_size, which is 2990 // different from libc sizeof(sigset_t). For the majority of architectures, 2991 // it's 64 bits (_NSIG), and libc NSIG is _NSIG + 1. 2992 const auto kernelSigsetSize = NSIG / 8; 2993 [[maybe_unused]] const int Result = syscall( 2994 SYS_rt_sigprocmask, /*how=*/~0, sigsetAddr, nullptr, kernelSigsetSize); 2995 // Because our "how" is invalid, this syscall should always fail, and our 2996 // errno should always be EINVAL or an EFAULT. This relies on the Linux 2997 // kernel to check copy_from_user before checking if the "how" argument is 2998 // invalid. 2999 assert(Result == -1); 3000 assert(errno == EFAULT || errno == EINVAL); 3001 const auto readable = errno != EFAULT; 3002 errno = saveErrno; 3003 return readable; 3004 } 3005 #endif 3006 3007 #if defined(_LIBUNWIND_USE_CET) 3008 extern "C" void *__libunwind_cet_get_registers(unw_cursor_t *cursor) { 3009 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor; 3010 return co->get_registers(); 3011 } 3012 #endif 3013 } // namespace libunwind 3014 3015 #endif // __UNWINDCURSOR_HPP__ 3016