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_S390X)) 35 #include <sys/syscall.h> 36 #include <sys/uio.h> 37 #include <unistd.h> 38 #define _LIBUNWIND_CHECK_LINUX_SIGRETURN 1 39 #endif 40 41 #include "AddressSpace.hpp" 42 #include "CompactUnwinder.hpp" 43 #include "config.h" 44 #include "DwarfInstructions.hpp" 45 #include "EHHeaderParser.hpp" 46 #include "libunwind.h" 47 #include "libunwind_ext.h" 48 #include "Registers.hpp" 49 #include "RWMutex.hpp" 50 #include "Unwind-EHABI.h" 51 52 #if defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) 53 // Provide a definition for the DISPATCHER_CONTEXT struct for old (Win7 and 54 // earlier) SDKs. 55 // MinGW-w64 has always provided this struct. 56 #if defined(_WIN32) && defined(_LIBUNWIND_TARGET_X86_64) && \ 57 !defined(__MINGW32__) && VER_PRODUCTBUILD < 8000 58 struct _DISPATCHER_CONTEXT { 59 ULONG64 ControlPc; 60 ULONG64 ImageBase; 61 PRUNTIME_FUNCTION FunctionEntry; 62 ULONG64 EstablisherFrame; 63 ULONG64 TargetIp; 64 PCONTEXT ContextRecord; 65 PEXCEPTION_ROUTINE LanguageHandler; 66 PVOID HandlerData; 67 PUNWIND_HISTORY_TABLE HistoryTable; 68 ULONG ScopeIndex; 69 ULONG Fill0; 70 }; 71 #endif 72 73 struct UNWIND_INFO { 74 uint8_t Version : 3; 75 uint8_t Flags : 5; 76 uint8_t SizeOfProlog; 77 uint8_t CountOfCodes; 78 uint8_t FrameRegister : 4; 79 uint8_t FrameOffset : 4; 80 uint16_t UnwindCodes[2]; 81 }; 82 83 extern "C" _Unwind_Reason_Code __libunwind_seh_personality( 84 int, _Unwind_Action, uint64_t, _Unwind_Exception *, 85 struct _Unwind_Context *); 86 87 #endif 88 89 namespace libunwind { 90 91 static thread_local UnwindInfoSectionsCache uwis_cache; 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) { _dispContext = *disp; } 512 513 // libunwind does not and should not depend on C++ library which means that we 514 // need our own definition of inline placement new. 515 static void *operator new(size_t, UnwindCursor<A, R> *p) { return p; } 516 517 private: 518 519 pint_t getLastPC() const { return _dispContext.ControlPc; } 520 void setLastPC(pint_t pc) { _dispContext.ControlPc = pc; } 521 RUNTIME_FUNCTION *lookUpSEHUnwindInfo(pint_t pc, pint_t *base) { 522 #ifdef __arm__ 523 // Remove the thumb bit; FunctionEntry ranges don't include the thumb bit. 524 pc &= ~1U; 525 #endif 526 // If pc points exactly at the end of the range, we might resolve the 527 // next function instead. Decrement pc by 1 to fit inside the current 528 // function. 529 pc -= 1; 530 _dispContext.FunctionEntry = RtlLookupFunctionEntry(pc, 531 &_dispContext.ImageBase, 532 _dispContext.HistoryTable); 533 *base = _dispContext.ImageBase; 534 return _dispContext.FunctionEntry; 535 } 536 bool getInfoFromSEH(pint_t pc); 537 int stepWithSEHData() { 538 _dispContext.LanguageHandler = RtlVirtualUnwind(UNW_FLAG_UHANDLER, 539 _dispContext.ImageBase, 540 _dispContext.ControlPc, 541 _dispContext.FunctionEntry, 542 _dispContext.ContextRecord, 543 &_dispContext.HandlerData, 544 &_dispContext.EstablisherFrame, 545 NULL); 546 // Update some fields of the unwind info now, since we have them. 547 _info.lsda = reinterpret_cast<unw_word_t>(_dispContext.HandlerData); 548 if (_dispContext.LanguageHandler) { 549 _info.handler = reinterpret_cast<unw_word_t>(__libunwind_seh_personality); 550 } else 551 _info.handler = 0; 552 return UNW_STEP_SUCCESS; 553 } 554 555 A &_addressSpace; 556 unw_proc_info_t _info; 557 DISPATCHER_CONTEXT _dispContext; 558 CONTEXT _msContext; 559 UNWIND_HISTORY_TABLE _histTable; 560 bool _unwindInfoMissing; 561 }; 562 563 564 template <typename A, typename R> 565 UnwindCursor<A, R>::UnwindCursor(unw_context_t *context, A &as) 566 : _addressSpace(as), _unwindInfoMissing(false) { 567 static_assert((check_fit<UnwindCursor<A, R>, unw_cursor_t>::does_fit), 568 "UnwindCursor<> does not fit in unw_cursor_t"); 569 static_assert((alignof(UnwindCursor<A, R>) <= alignof(unw_cursor_t)), 570 "UnwindCursor<> requires more alignment than unw_cursor_t"); 571 memset(&_info, 0, sizeof(_info)); 572 memset(&_histTable, 0, sizeof(_histTable)); 573 _dispContext.ContextRecord = &_msContext; 574 _dispContext.HistoryTable = &_histTable; 575 // Initialize MS context from ours. 576 R r(context); 577 _msContext.ContextFlags = CONTEXT_CONTROL|CONTEXT_INTEGER|CONTEXT_FLOATING_POINT; 578 #if defined(_LIBUNWIND_TARGET_X86_64) 579 _msContext.Rax = r.getRegister(UNW_X86_64_RAX); 580 _msContext.Rcx = r.getRegister(UNW_X86_64_RCX); 581 _msContext.Rdx = r.getRegister(UNW_X86_64_RDX); 582 _msContext.Rbx = r.getRegister(UNW_X86_64_RBX); 583 _msContext.Rsp = r.getRegister(UNW_X86_64_RSP); 584 _msContext.Rbp = r.getRegister(UNW_X86_64_RBP); 585 _msContext.Rsi = r.getRegister(UNW_X86_64_RSI); 586 _msContext.Rdi = r.getRegister(UNW_X86_64_RDI); 587 _msContext.R8 = r.getRegister(UNW_X86_64_R8); 588 _msContext.R9 = r.getRegister(UNW_X86_64_R9); 589 _msContext.R10 = r.getRegister(UNW_X86_64_R10); 590 _msContext.R11 = r.getRegister(UNW_X86_64_R11); 591 _msContext.R12 = r.getRegister(UNW_X86_64_R12); 592 _msContext.R13 = r.getRegister(UNW_X86_64_R13); 593 _msContext.R14 = r.getRegister(UNW_X86_64_R14); 594 _msContext.R15 = r.getRegister(UNW_X86_64_R15); 595 _msContext.Rip = r.getRegister(UNW_REG_IP); 596 union { 597 v128 v; 598 M128A m; 599 } t; 600 t.v = r.getVectorRegister(UNW_X86_64_XMM0); 601 _msContext.Xmm0 = t.m; 602 t.v = r.getVectorRegister(UNW_X86_64_XMM1); 603 _msContext.Xmm1 = t.m; 604 t.v = r.getVectorRegister(UNW_X86_64_XMM2); 605 _msContext.Xmm2 = t.m; 606 t.v = r.getVectorRegister(UNW_X86_64_XMM3); 607 _msContext.Xmm3 = t.m; 608 t.v = r.getVectorRegister(UNW_X86_64_XMM4); 609 _msContext.Xmm4 = t.m; 610 t.v = r.getVectorRegister(UNW_X86_64_XMM5); 611 _msContext.Xmm5 = t.m; 612 t.v = r.getVectorRegister(UNW_X86_64_XMM6); 613 _msContext.Xmm6 = t.m; 614 t.v = r.getVectorRegister(UNW_X86_64_XMM7); 615 _msContext.Xmm7 = t.m; 616 t.v = r.getVectorRegister(UNW_X86_64_XMM8); 617 _msContext.Xmm8 = t.m; 618 t.v = r.getVectorRegister(UNW_X86_64_XMM9); 619 _msContext.Xmm9 = t.m; 620 t.v = r.getVectorRegister(UNW_X86_64_XMM10); 621 _msContext.Xmm10 = t.m; 622 t.v = r.getVectorRegister(UNW_X86_64_XMM11); 623 _msContext.Xmm11 = t.m; 624 t.v = r.getVectorRegister(UNW_X86_64_XMM12); 625 _msContext.Xmm12 = t.m; 626 t.v = r.getVectorRegister(UNW_X86_64_XMM13); 627 _msContext.Xmm13 = t.m; 628 t.v = r.getVectorRegister(UNW_X86_64_XMM14); 629 _msContext.Xmm14 = t.m; 630 t.v = r.getVectorRegister(UNW_X86_64_XMM15); 631 _msContext.Xmm15 = t.m; 632 #elif defined(_LIBUNWIND_TARGET_ARM) 633 _msContext.R0 = r.getRegister(UNW_ARM_R0); 634 _msContext.R1 = r.getRegister(UNW_ARM_R1); 635 _msContext.R2 = r.getRegister(UNW_ARM_R2); 636 _msContext.R3 = r.getRegister(UNW_ARM_R3); 637 _msContext.R4 = r.getRegister(UNW_ARM_R4); 638 _msContext.R5 = r.getRegister(UNW_ARM_R5); 639 _msContext.R6 = r.getRegister(UNW_ARM_R6); 640 _msContext.R7 = r.getRegister(UNW_ARM_R7); 641 _msContext.R8 = r.getRegister(UNW_ARM_R8); 642 _msContext.R9 = r.getRegister(UNW_ARM_R9); 643 _msContext.R10 = r.getRegister(UNW_ARM_R10); 644 _msContext.R11 = r.getRegister(UNW_ARM_R11); 645 _msContext.R12 = r.getRegister(UNW_ARM_R12); 646 _msContext.Sp = r.getRegister(UNW_ARM_SP); 647 _msContext.Lr = r.getRegister(UNW_ARM_LR); 648 _msContext.Pc = r.getRegister(UNW_ARM_IP); 649 for (int i = UNW_ARM_D0; i <= UNW_ARM_D31; ++i) { 650 union { 651 uint64_t w; 652 double d; 653 } d; 654 d.d = r.getFloatRegister(i); 655 _msContext.D[i - UNW_ARM_D0] = d.w; 656 } 657 #elif defined(_LIBUNWIND_TARGET_AARCH64) 658 for (int i = UNW_AARCH64_X0; i <= UNW_ARM64_X30; ++i) 659 _msContext.X[i - UNW_AARCH64_X0] = r.getRegister(i); 660 _msContext.Sp = r.getRegister(UNW_REG_SP); 661 _msContext.Pc = r.getRegister(UNW_REG_IP); 662 for (int i = UNW_AARCH64_V0; i <= UNW_ARM64_D31; ++i) 663 _msContext.V[i - UNW_AARCH64_V0].D[0] = r.getFloatRegister(i); 664 #endif 665 } 666 667 template <typename A, typename R> 668 UnwindCursor<A, R>::UnwindCursor(CONTEXT *context, A &as) 669 : _addressSpace(as), _unwindInfoMissing(false) { 670 static_assert((check_fit<UnwindCursor<A, R>, unw_cursor_t>::does_fit), 671 "UnwindCursor<> does not fit in unw_cursor_t"); 672 memset(&_info, 0, sizeof(_info)); 673 memset(&_histTable, 0, sizeof(_histTable)); 674 _dispContext.ContextRecord = &_msContext; 675 _dispContext.HistoryTable = &_histTable; 676 _msContext = *context; 677 } 678 679 680 template <typename A, typename R> 681 bool UnwindCursor<A, R>::validReg(int regNum) { 682 if (regNum == UNW_REG_IP || regNum == UNW_REG_SP) return true; 683 #if defined(_LIBUNWIND_TARGET_X86_64) 684 if (regNum >= UNW_X86_64_RAX && regNum <= UNW_X86_64_R15) return true; 685 #elif defined(_LIBUNWIND_TARGET_ARM) 686 if ((regNum >= UNW_ARM_R0 && regNum <= UNW_ARM_R15) || 687 regNum == UNW_ARM_RA_AUTH_CODE) 688 return true; 689 #elif defined(_LIBUNWIND_TARGET_AARCH64) 690 if (regNum >= UNW_AARCH64_X0 && regNum <= UNW_ARM64_X30) return true; 691 #endif 692 return false; 693 } 694 695 template <typename A, typename R> 696 unw_word_t UnwindCursor<A, R>::getReg(int regNum) { 697 switch (regNum) { 698 #if defined(_LIBUNWIND_TARGET_X86_64) 699 case UNW_REG_IP: return _msContext.Rip; 700 case UNW_X86_64_RAX: return _msContext.Rax; 701 case UNW_X86_64_RDX: return _msContext.Rdx; 702 case UNW_X86_64_RCX: return _msContext.Rcx; 703 case UNW_X86_64_RBX: return _msContext.Rbx; 704 case UNW_REG_SP: 705 case UNW_X86_64_RSP: return _msContext.Rsp; 706 case UNW_X86_64_RBP: return _msContext.Rbp; 707 case UNW_X86_64_RSI: return _msContext.Rsi; 708 case UNW_X86_64_RDI: return _msContext.Rdi; 709 case UNW_X86_64_R8: return _msContext.R8; 710 case UNW_X86_64_R9: return _msContext.R9; 711 case UNW_X86_64_R10: return _msContext.R10; 712 case UNW_X86_64_R11: return _msContext.R11; 713 case UNW_X86_64_R12: return _msContext.R12; 714 case UNW_X86_64_R13: return _msContext.R13; 715 case UNW_X86_64_R14: return _msContext.R14; 716 case UNW_X86_64_R15: return _msContext.R15; 717 #elif defined(_LIBUNWIND_TARGET_ARM) 718 case UNW_ARM_R0: return _msContext.R0; 719 case UNW_ARM_R1: return _msContext.R1; 720 case UNW_ARM_R2: return _msContext.R2; 721 case UNW_ARM_R3: return _msContext.R3; 722 case UNW_ARM_R4: return _msContext.R4; 723 case UNW_ARM_R5: return _msContext.R5; 724 case UNW_ARM_R6: return _msContext.R6; 725 case UNW_ARM_R7: return _msContext.R7; 726 case UNW_ARM_R8: return _msContext.R8; 727 case UNW_ARM_R9: return _msContext.R9; 728 case UNW_ARM_R10: return _msContext.R10; 729 case UNW_ARM_R11: return _msContext.R11; 730 case UNW_ARM_R12: return _msContext.R12; 731 case UNW_REG_SP: 732 case UNW_ARM_SP: return _msContext.Sp; 733 case UNW_ARM_LR: return _msContext.Lr; 734 case UNW_REG_IP: 735 case UNW_ARM_IP: return _msContext.Pc; 736 #elif defined(_LIBUNWIND_TARGET_AARCH64) 737 case UNW_REG_SP: return _msContext.Sp; 738 case UNW_REG_IP: return _msContext.Pc; 739 default: return _msContext.X[regNum - UNW_AARCH64_X0]; 740 #endif 741 } 742 _LIBUNWIND_ABORT("unsupported register"); 743 } 744 745 template <typename A, typename R> 746 void UnwindCursor<A, R>::setReg(int regNum, unw_word_t value) { 747 switch (regNum) { 748 #if defined(_LIBUNWIND_TARGET_X86_64) 749 case UNW_REG_IP: _msContext.Rip = value; break; 750 case UNW_X86_64_RAX: _msContext.Rax = value; break; 751 case UNW_X86_64_RDX: _msContext.Rdx = value; break; 752 case UNW_X86_64_RCX: _msContext.Rcx = value; break; 753 case UNW_X86_64_RBX: _msContext.Rbx = value; break; 754 case UNW_REG_SP: 755 case UNW_X86_64_RSP: _msContext.Rsp = value; break; 756 case UNW_X86_64_RBP: _msContext.Rbp = value; break; 757 case UNW_X86_64_RSI: _msContext.Rsi = value; break; 758 case UNW_X86_64_RDI: _msContext.Rdi = value; break; 759 case UNW_X86_64_R8: _msContext.R8 = value; break; 760 case UNW_X86_64_R9: _msContext.R9 = value; break; 761 case UNW_X86_64_R10: _msContext.R10 = value; break; 762 case UNW_X86_64_R11: _msContext.R11 = value; break; 763 case UNW_X86_64_R12: _msContext.R12 = value; break; 764 case UNW_X86_64_R13: _msContext.R13 = value; break; 765 case UNW_X86_64_R14: _msContext.R14 = value; break; 766 case UNW_X86_64_R15: _msContext.R15 = value; break; 767 #elif defined(_LIBUNWIND_TARGET_ARM) 768 case UNW_ARM_R0: _msContext.R0 = value; break; 769 case UNW_ARM_R1: _msContext.R1 = value; break; 770 case UNW_ARM_R2: _msContext.R2 = value; break; 771 case UNW_ARM_R3: _msContext.R3 = value; break; 772 case UNW_ARM_R4: _msContext.R4 = value; break; 773 case UNW_ARM_R5: _msContext.R5 = value; break; 774 case UNW_ARM_R6: _msContext.R6 = value; break; 775 case UNW_ARM_R7: _msContext.R7 = value; break; 776 case UNW_ARM_R8: _msContext.R8 = value; break; 777 case UNW_ARM_R9: _msContext.R9 = value; break; 778 case UNW_ARM_R10: _msContext.R10 = value; break; 779 case UNW_ARM_R11: _msContext.R11 = value; break; 780 case UNW_ARM_R12: _msContext.R12 = value; break; 781 case UNW_REG_SP: 782 case UNW_ARM_SP: _msContext.Sp = value; break; 783 case UNW_ARM_LR: _msContext.Lr = value; break; 784 case UNW_REG_IP: 785 case UNW_ARM_IP: _msContext.Pc = value; break; 786 #elif defined(_LIBUNWIND_TARGET_AARCH64) 787 case UNW_REG_SP: _msContext.Sp = value; break; 788 case UNW_REG_IP: _msContext.Pc = value; break; 789 case UNW_AARCH64_X0: 790 case UNW_AARCH64_X1: 791 case UNW_AARCH64_X2: 792 case UNW_AARCH64_X3: 793 case UNW_AARCH64_X4: 794 case UNW_AARCH64_X5: 795 case UNW_AARCH64_X6: 796 case UNW_AARCH64_X7: 797 case UNW_AARCH64_X8: 798 case UNW_AARCH64_X9: 799 case UNW_AARCH64_X10: 800 case UNW_AARCH64_X11: 801 case UNW_AARCH64_X12: 802 case UNW_AARCH64_X13: 803 case UNW_AARCH64_X14: 804 case UNW_AARCH64_X15: 805 case UNW_AARCH64_X16: 806 case UNW_AARCH64_X17: 807 case UNW_AARCH64_X18: 808 case UNW_AARCH64_X19: 809 case UNW_AARCH64_X20: 810 case UNW_AARCH64_X21: 811 case UNW_AARCH64_X22: 812 case UNW_AARCH64_X23: 813 case UNW_AARCH64_X24: 814 case UNW_AARCH64_X25: 815 case UNW_AARCH64_X26: 816 case UNW_AARCH64_X27: 817 case UNW_AARCH64_X28: 818 case UNW_AARCH64_FP: 819 case UNW_AARCH64_LR: _msContext.X[regNum - UNW_ARM64_X0] = value; break; 820 #endif 821 default: 822 _LIBUNWIND_ABORT("unsupported register"); 823 } 824 } 825 826 template <typename A, typename R> 827 bool UnwindCursor<A, R>::validFloatReg(int regNum) { 828 #if defined(_LIBUNWIND_TARGET_ARM) 829 if (regNum >= UNW_ARM_S0 && regNum <= UNW_ARM_S31) return true; 830 if (regNum >= UNW_ARM_D0 && regNum <= UNW_ARM_D31) return true; 831 #elif defined(_LIBUNWIND_TARGET_AARCH64) 832 if (regNum >= UNW_AARCH64_V0 && regNum <= UNW_ARM64_D31) return true; 833 #else 834 (void)regNum; 835 #endif 836 return false; 837 } 838 839 template <typename A, typename R> 840 unw_fpreg_t UnwindCursor<A, R>::getFloatReg(int regNum) { 841 #if defined(_LIBUNWIND_TARGET_ARM) 842 if (regNum >= UNW_ARM_S0 && regNum <= UNW_ARM_S31) { 843 union { 844 uint32_t w; 845 float f; 846 } d; 847 d.w = _msContext.S[regNum - UNW_ARM_S0]; 848 return d.f; 849 } 850 if (regNum >= UNW_ARM_D0 && regNum <= UNW_ARM_D31) { 851 union { 852 uint64_t w; 853 double d; 854 } d; 855 d.w = _msContext.D[regNum - UNW_ARM_D0]; 856 return d.d; 857 } 858 _LIBUNWIND_ABORT("unsupported float register"); 859 #elif defined(_LIBUNWIND_TARGET_AARCH64) 860 return _msContext.V[regNum - UNW_AARCH64_V0].D[0]; 861 #else 862 (void)regNum; 863 _LIBUNWIND_ABORT("float registers unimplemented"); 864 #endif 865 } 866 867 template <typename A, typename R> 868 void UnwindCursor<A, R>::setFloatReg(int regNum, unw_fpreg_t value) { 869 #if defined(_LIBUNWIND_TARGET_ARM) 870 if (regNum >= UNW_ARM_S0 && regNum <= UNW_ARM_S31) { 871 union { 872 uint32_t w; 873 float f; 874 } d; 875 d.f = (float)value; 876 _msContext.S[regNum - UNW_ARM_S0] = d.w; 877 } 878 if (regNum >= UNW_ARM_D0 && regNum <= UNW_ARM_D31) { 879 union { 880 uint64_t w; 881 double d; 882 } d; 883 d.d = value; 884 _msContext.D[regNum - UNW_ARM_D0] = d.w; 885 } 886 _LIBUNWIND_ABORT("unsupported float register"); 887 #elif defined(_LIBUNWIND_TARGET_AARCH64) 888 _msContext.V[regNum - UNW_AARCH64_V0].D[0] = value; 889 #else 890 (void)regNum; 891 (void)value; 892 _LIBUNWIND_ABORT("float registers unimplemented"); 893 #endif 894 } 895 896 template <typename A, typename R> void UnwindCursor<A, R>::jumpto() { 897 RtlRestoreContext(&_msContext, nullptr); 898 } 899 900 #ifdef __arm__ 901 template <typename A, typename R> void UnwindCursor<A, R>::saveVFPAsX() {} 902 #endif 903 904 template <typename A, typename R> 905 const char *UnwindCursor<A, R>::getRegisterName(int regNum) { 906 return R::getRegisterName(regNum); 907 } 908 909 template <typename A, typename R> bool UnwindCursor<A, R>::isSignalFrame() { 910 return false; 911 } 912 913 #else // !defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) || !defined(_WIN32) 914 915 /// UnwindCursor contains all state (including all register values) during 916 /// an unwind. This is normally stack allocated inside a unw_cursor_t. 917 template <typename A, typename R> 918 class UnwindCursor : public AbstractUnwindCursor{ 919 typedef typename A::pint_t pint_t; 920 public: 921 UnwindCursor(unw_context_t *context, A &as); 922 UnwindCursor(A &as, void *threadArg); 923 virtual ~UnwindCursor() {} 924 virtual bool validReg(int); 925 virtual unw_word_t getReg(int); 926 virtual void setReg(int, unw_word_t); 927 virtual bool validFloatReg(int); 928 virtual unw_fpreg_t getFloatReg(int); 929 virtual void setFloatReg(int, unw_fpreg_t); 930 virtual int step(bool stage2 = false); 931 virtual void getInfo(unw_proc_info_t *); 932 virtual void jumpto(); 933 virtual bool isSignalFrame(); 934 virtual bool getFunctionName(char *buf, size_t len, unw_word_t *off); 935 virtual void setInfoBasedOnIPRegister(bool isReturnAddress = false); 936 virtual const char *getRegisterName(int num); 937 #ifdef __arm__ 938 virtual void saveVFPAsX(); 939 #endif 940 941 #ifdef _AIX 942 virtual uintptr_t getDataRelBase(); 943 #endif 944 945 #if defined(_LIBUNWIND_USE_CET) 946 virtual void *get_registers() { return &_registers; } 947 #endif 948 949 // libunwind does not and should not depend on C++ library which means that we 950 // need our own definition of inline placement new. 951 static void *operator new(size_t, UnwindCursor<A, R> *p) { return p; } 952 953 private: 954 955 #if defined(_LIBUNWIND_ARM_EHABI) 956 bool getInfoFromEHABISection(pint_t pc, const UnwindInfoSections §s); 957 958 int stepWithEHABI() { 959 size_t len = 0; 960 size_t off = 0; 961 // FIXME: Calling decode_eht_entry() here is violating the libunwind 962 // abstraction layer. 963 const uint32_t *ehtp = 964 decode_eht_entry(reinterpret_cast<const uint32_t *>(_info.unwind_info), 965 &off, &len); 966 if (_Unwind_VRS_Interpret((_Unwind_Context *)this, ehtp, off, len) != 967 _URC_CONTINUE_UNWIND) 968 return UNW_STEP_END; 969 return UNW_STEP_SUCCESS; 970 } 971 #endif 972 973 #if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) 974 bool setInfoForSigReturn() { 975 R dummy; 976 return setInfoForSigReturn(dummy); 977 } 978 int stepThroughSigReturn() { 979 R dummy; 980 return stepThroughSigReturn(dummy); 981 } 982 #if defined(_LIBUNWIND_TARGET_AARCH64) 983 bool setInfoForSigReturn(Registers_arm64 &); 984 int stepThroughSigReturn(Registers_arm64 &); 985 #endif 986 #if defined(_LIBUNWIND_TARGET_S390X) 987 bool setInfoForSigReturn(Registers_s390x &); 988 int stepThroughSigReturn(Registers_s390x &); 989 #endif 990 template <typename Registers> bool setInfoForSigReturn(Registers &) { 991 return false; 992 } 993 template <typename Registers> int stepThroughSigReturn(Registers &) { 994 return UNW_STEP_END; 995 } 996 #endif 997 998 #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 999 bool getInfoFromFdeCie(const typename CFI_Parser<A>::FDE_Info &fdeInfo, 1000 const typename CFI_Parser<A>::CIE_Info &cieInfo, 1001 pint_t pc, uintptr_t dso_base); 1002 bool getInfoFromDwarfSection(pint_t pc, const UnwindInfoSections §s, 1003 uint32_t fdeSectionOffsetHint=0); 1004 int stepWithDwarfFDE(bool stage2) { 1005 return DwarfInstructions<A, R>::stepWithDwarf( 1006 _addressSpace, (pint_t)this->getReg(UNW_REG_IP), 1007 (pint_t)_info.unwind_info, _registers, _isSignalFrame, stage2); 1008 } 1009 #endif 1010 1011 #if defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND) 1012 bool getInfoFromCompactEncodingSection(pint_t pc, 1013 const UnwindInfoSections §s); 1014 int stepWithCompactEncoding(bool stage2 = false) { 1015 #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 1016 if ( compactSaysUseDwarf() ) 1017 return stepWithDwarfFDE(stage2); 1018 #endif 1019 R dummy; 1020 return stepWithCompactEncoding(dummy); 1021 } 1022 1023 #if defined(_LIBUNWIND_TARGET_X86_64) 1024 int stepWithCompactEncoding(Registers_x86_64 &) { 1025 return CompactUnwinder_x86_64<A>::stepWithCompactEncoding( 1026 _info.format, _info.start_ip, _addressSpace, _registers); 1027 } 1028 #endif 1029 1030 #if defined(_LIBUNWIND_TARGET_I386) 1031 int stepWithCompactEncoding(Registers_x86 &) { 1032 return CompactUnwinder_x86<A>::stepWithCompactEncoding( 1033 _info.format, (uint32_t)_info.start_ip, _addressSpace, _registers); 1034 } 1035 #endif 1036 1037 #if defined(_LIBUNWIND_TARGET_PPC) 1038 int stepWithCompactEncoding(Registers_ppc &) { 1039 return UNW_EINVAL; 1040 } 1041 #endif 1042 1043 #if defined(_LIBUNWIND_TARGET_PPC64) 1044 int stepWithCompactEncoding(Registers_ppc64 &) { 1045 return UNW_EINVAL; 1046 } 1047 #endif 1048 1049 1050 #if defined(_LIBUNWIND_TARGET_AARCH64) 1051 int stepWithCompactEncoding(Registers_arm64 &) { 1052 return CompactUnwinder_arm64<A>::stepWithCompactEncoding( 1053 _info.format, _info.start_ip, _addressSpace, _registers); 1054 } 1055 #endif 1056 1057 #if defined(_LIBUNWIND_TARGET_MIPS_O32) 1058 int stepWithCompactEncoding(Registers_mips_o32 &) { 1059 return UNW_EINVAL; 1060 } 1061 #endif 1062 1063 #if defined(_LIBUNWIND_TARGET_MIPS_NEWABI) 1064 int stepWithCompactEncoding(Registers_mips_newabi &) { 1065 return UNW_EINVAL; 1066 } 1067 #endif 1068 1069 #if defined(_LIBUNWIND_TARGET_LOONGARCH) 1070 int stepWithCompactEncoding(Registers_loongarch &) { return UNW_EINVAL; } 1071 #endif 1072 1073 #if defined(_LIBUNWIND_TARGET_SPARC) 1074 int stepWithCompactEncoding(Registers_sparc &) { return UNW_EINVAL; } 1075 #endif 1076 1077 #if defined(_LIBUNWIND_TARGET_SPARC64) 1078 int stepWithCompactEncoding(Registers_sparc64 &) { return UNW_EINVAL; } 1079 #endif 1080 1081 #if defined (_LIBUNWIND_TARGET_RISCV) 1082 int stepWithCompactEncoding(Registers_riscv &) { 1083 return UNW_EINVAL; 1084 } 1085 #endif 1086 1087 bool compactSaysUseDwarf(uint32_t *offset=NULL) const { 1088 R dummy; 1089 return compactSaysUseDwarf(dummy, offset); 1090 } 1091 1092 #if defined(_LIBUNWIND_TARGET_X86_64) 1093 bool compactSaysUseDwarf(Registers_x86_64 &, uint32_t *offset) const { 1094 if ((_info.format & UNWIND_X86_64_MODE_MASK) == UNWIND_X86_64_MODE_DWARF) { 1095 if (offset) 1096 *offset = (_info.format & UNWIND_X86_64_DWARF_SECTION_OFFSET); 1097 return true; 1098 } 1099 return false; 1100 } 1101 #endif 1102 1103 #if defined(_LIBUNWIND_TARGET_I386) 1104 bool compactSaysUseDwarf(Registers_x86 &, uint32_t *offset) const { 1105 if ((_info.format & UNWIND_X86_MODE_MASK) == UNWIND_X86_MODE_DWARF) { 1106 if (offset) 1107 *offset = (_info.format & UNWIND_X86_DWARF_SECTION_OFFSET); 1108 return true; 1109 } 1110 return false; 1111 } 1112 #endif 1113 1114 #if defined(_LIBUNWIND_TARGET_PPC) 1115 bool compactSaysUseDwarf(Registers_ppc &, uint32_t *) const { 1116 return true; 1117 } 1118 #endif 1119 1120 #if defined(_LIBUNWIND_TARGET_PPC64) 1121 bool compactSaysUseDwarf(Registers_ppc64 &, uint32_t *) const { 1122 return true; 1123 } 1124 #endif 1125 1126 #if defined(_LIBUNWIND_TARGET_AARCH64) 1127 bool compactSaysUseDwarf(Registers_arm64 &, uint32_t *offset) const { 1128 if ((_info.format & UNWIND_ARM64_MODE_MASK) == UNWIND_ARM64_MODE_DWARF) { 1129 if (offset) 1130 *offset = (_info.format & UNWIND_ARM64_DWARF_SECTION_OFFSET); 1131 return true; 1132 } 1133 return false; 1134 } 1135 #endif 1136 1137 #if defined(_LIBUNWIND_TARGET_MIPS_O32) 1138 bool compactSaysUseDwarf(Registers_mips_o32 &, uint32_t *) const { 1139 return true; 1140 } 1141 #endif 1142 1143 #if defined(_LIBUNWIND_TARGET_MIPS_NEWABI) 1144 bool compactSaysUseDwarf(Registers_mips_newabi &, uint32_t *) const { 1145 return true; 1146 } 1147 #endif 1148 1149 #if defined(_LIBUNWIND_TARGET_LOONGARCH) 1150 bool compactSaysUseDwarf(Registers_loongarch &, uint32_t *) const { 1151 return true; 1152 } 1153 #endif 1154 1155 #if defined(_LIBUNWIND_TARGET_SPARC) 1156 bool compactSaysUseDwarf(Registers_sparc &, uint32_t *) const { return true; } 1157 #endif 1158 1159 #if defined(_LIBUNWIND_TARGET_SPARC64) 1160 bool compactSaysUseDwarf(Registers_sparc64 &, uint32_t *) const { 1161 return true; 1162 } 1163 #endif 1164 1165 #if defined (_LIBUNWIND_TARGET_RISCV) 1166 bool compactSaysUseDwarf(Registers_riscv &, uint32_t *) const { 1167 return true; 1168 } 1169 #endif 1170 1171 #endif // defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND) 1172 1173 #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 1174 compact_unwind_encoding_t dwarfEncoding() const { 1175 R dummy; 1176 return dwarfEncoding(dummy); 1177 } 1178 1179 #if defined(_LIBUNWIND_TARGET_X86_64) 1180 compact_unwind_encoding_t dwarfEncoding(Registers_x86_64 &) const { 1181 return UNWIND_X86_64_MODE_DWARF; 1182 } 1183 #endif 1184 1185 #if defined(_LIBUNWIND_TARGET_I386) 1186 compact_unwind_encoding_t dwarfEncoding(Registers_x86 &) const { 1187 return UNWIND_X86_MODE_DWARF; 1188 } 1189 #endif 1190 1191 #if defined(_LIBUNWIND_TARGET_PPC) 1192 compact_unwind_encoding_t dwarfEncoding(Registers_ppc &) const { 1193 return 0; 1194 } 1195 #endif 1196 1197 #if defined(_LIBUNWIND_TARGET_PPC64) 1198 compact_unwind_encoding_t dwarfEncoding(Registers_ppc64 &) const { 1199 return 0; 1200 } 1201 #endif 1202 1203 #if defined(_LIBUNWIND_TARGET_AARCH64) 1204 compact_unwind_encoding_t dwarfEncoding(Registers_arm64 &) const { 1205 return UNWIND_ARM64_MODE_DWARF; 1206 } 1207 #endif 1208 1209 #if defined(_LIBUNWIND_TARGET_ARM) 1210 compact_unwind_encoding_t dwarfEncoding(Registers_arm &) const { 1211 return 0; 1212 } 1213 #endif 1214 1215 #if defined (_LIBUNWIND_TARGET_OR1K) 1216 compact_unwind_encoding_t dwarfEncoding(Registers_or1k &) const { 1217 return 0; 1218 } 1219 #endif 1220 1221 #if defined (_LIBUNWIND_TARGET_HEXAGON) 1222 compact_unwind_encoding_t dwarfEncoding(Registers_hexagon &) const { 1223 return 0; 1224 } 1225 #endif 1226 1227 #if defined (_LIBUNWIND_TARGET_MIPS_O32) 1228 compact_unwind_encoding_t dwarfEncoding(Registers_mips_o32 &) const { 1229 return 0; 1230 } 1231 #endif 1232 1233 #if defined (_LIBUNWIND_TARGET_MIPS_NEWABI) 1234 compact_unwind_encoding_t dwarfEncoding(Registers_mips_newabi &) const { 1235 return 0; 1236 } 1237 #endif 1238 1239 #if defined(_LIBUNWIND_TARGET_LOONGARCH) 1240 compact_unwind_encoding_t dwarfEncoding(Registers_loongarch &) const { 1241 return 0; 1242 } 1243 #endif 1244 1245 #if defined(_LIBUNWIND_TARGET_SPARC) 1246 compact_unwind_encoding_t dwarfEncoding(Registers_sparc &) const { return 0; } 1247 #endif 1248 1249 #if defined(_LIBUNWIND_TARGET_SPARC64) 1250 compact_unwind_encoding_t dwarfEncoding(Registers_sparc64 &) const { 1251 return 0; 1252 } 1253 #endif 1254 1255 #if defined (_LIBUNWIND_TARGET_RISCV) 1256 compact_unwind_encoding_t dwarfEncoding(Registers_riscv &) const { 1257 return 0; 1258 } 1259 #endif 1260 1261 #if defined (_LIBUNWIND_TARGET_S390X) 1262 compact_unwind_encoding_t dwarfEncoding(Registers_s390x &) const { 1263 return 0; 1264 } 1265 #endif 1266 1267 #endif // defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 1268 1269 #if defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) 1270 // For runtime environments using SEH unwind data without Windows runtime 1271 // support. 1272 pint_t getLastPC() const { /* FIXME: Implement */ return 0; } 1273 void setLastPC(pint_t pc) { /* FIXME: Implement */ } 1274 RUNTIME_FUNCTION *lookUpSEHUnwindInfo(pint_t pc, pint_t *base) { 1275 /* FIXME: Implement */ 1276 *base = 0; 1277 return nullptr; 1278 } 1279 bool getInfoFromSEH(pint_t pc); 1280 int stepWithSEHData() { /* FIXME: Implement */ return 0; } 1281 #endif // defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) 1282 1283 #if defined(_LIBUNWIND_SUPPORT_TBTAB_UNWIND) 1284 bool getInfoFromTBTable(pint_t pc, R ®isters); 1285 int stepWithTBTable(pint_t pc, tbtable *TBTable, R ®isters, 1286 bool &isSignalFrame); 1287 int stepWithTBTableData() { 1288 return stepWithTBTable(reinterpret_cast<pint_t>(this->getReg(UNW_REG_IP)), 1289 reinterpret_cast<tbtable *>(_info.unwind_info), 1290 _registers, _isSignalFrame); 1291 } 1292 #endif // defined(_LIBUNWIND_SUPPORT_TBTAB_UNWIND) 1293 1294 A &_addressSpace; 1295 R _registers; 1296 unw_proc_info_t _info; 1297 bool _unwindInfoMissing; 1298 bool _isSignalFrame; 1299 #if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) 1300 bool _isSigReturn = false; 1301 #endif 1302 }; 1303 1304 1305 template <typename A, typename R> 1306 UnwindCursor<A, R>::UnwindCursor(unw_context_t *context, A &as) 1307 : _addressSpace(as), _registers(context), _unwindInfoMissing(false), 1308 _isSignalFrame(false) { 1309 static_assert((check_fit<UnwindCursor<A, R>, unw_cursor_t>::does_fit), 1310 "UnwindCursor<> does not fit in unw_cursor_t"); 1311 static_assert((alignof(UnwindCursor<A, R>) <= alignof(unw_cursor_t)), 1312 "UnwindCursor<> requires more alignment than unw_cursor_t"); 1313 memset(&_info, 0, sizeof(_info)); 1314 } 1315 1316 template <typename A, typename R> 1317 UnwindCursor<A, R>::UnwindCursor(A &as, void *) 1318 : _addressSpace(as), _unwindInfoMissing(false), _isSignalFrame(false) { 1319 memset(&_info, 0, sizeof(_info)); 1320 // FIXME 1321 // fill in _registers from thread arg 1322 } 1323 1324 1325 template <typename A, typename R> 1326 bool UnwindCursor<A, R>::validReg(int regNum) { 1327 return _registers.validRegister(regNum); 1328 } 1329 1330 template <typename A, typename R> 1331 unw_word_t UnwindCursor<A, R>::getReg(int regNum) { 1332 return _registers.getRegister(regNum); 1333 } 1334 1335 template <typename A, typename R> 1336 void UnwindCursor<A, R>::setReg(int regNum, unw_word_t value) { 1337 _registers.setRegister(regNum, (typename A::pint_t)value); 1338 } 1339 1340 template <typename A, typename R> 1341 bool UnwindCursor<A, R>::validFloatReg(int regNum) { 1342 return _registers.validFloatRegister(regNum); 1343 } 1344 1345 template <typename A, typename R> 1346 unw_fpreg_t UnwindCursor<A, R>::getFloatReg(int regNum) { 1347 return _registers.getFloatRegister(regNum); 1348 } 1349 1350 template <typename A, typename R> 1351 void UnwindCursor<A, R>::setFloatReg(int regNum, unw_fpreg_t value) { 1352 _registers.setFloatRegister(regNum, value); 1353 } 1354 1355 template <typename A, typename R> void UnwindCursor<A, R>::jumpto() { 1356 _registers.jumpto(); 1357 } 1358 1359 #ifdef __arm__ 1360 template <typename A, typename R> void UnwindCursor<A, R>::saveVFPAsX() { 1361 _registers.saveVFPAsX(); 1362 } 1363 #endif 1364 1365 #ifdef _AIX 1366 template <typename A, typename R> 1367 uintptr_t UnwindCursor<A, R>::getDataRelBase() { 1368 return reinterpret_cast<uintptr_t>(_info.extra); 1369 } 1370 #endif 1371 1372 template <typename A, typename R> 1373 const char *UnwindCursor<A, R>::getRegisterName(int regNum) { 1374 return _registers.getRegisterName(regNum); 1375 } 1376 1377 template <typename A, typename R> bool UnwindCursor<A, R>::isSignalFrame() { 1378 return _isSignalFrame; 1379 } 1380 1381 #endif // defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) 1382 1383 #if defined(_LIBUNWIND_ARM_EHABI) 1384 template<typename A> 1385 struct EHABISectionIterator { 1386 typedef EHABISectionIterator _Self; 1387 1388 typedef typename A::pint_t value_type; 1389 typedef typename A::pint_t* pointer; 1390 typedef typename A::pint_t& reference; 1391 typedef size_t size_type; 1392 typedef size_t difference_type; 1393 1394 static _Self begin(A& addressSpace, const UnwindInfoSections& sects) { 1395 return _Self(addressSpace, sects, 0); 1396 } 1397 static _Self end(A& addressSpace, const UnwindInfoSections& sects) { 1398 return _Self(addressSpace, sects, 1399 sects.arm_section_length / sizeof(EHABIIndexEntry)); 1400 } 1401 1402 EHABISectionIterator(A& addressSpace, const UnwindInfoSections& sects, size_t i) 1403 : _i(i), _addressSpace(&addressSpace), _sects(§s) {} 1404 1405 _Self& operator++() { ++_i; return *this; } 1406 _Self& operator+=(size_t a) { _i += a; return *this; } 1407 _Self& operator--() { assert(_i > 0); --_i; return *this; } 1408 _Self& operator-=(size_t a) { assert(_i >= a); _i -= a; return *this; } 1409 1410 _Self operator+(size_t a) { _Self out = *this; out._i += a; return out; } 1411 _Self operator-(size_t a) { assert(_i >= a); _Self out = *this; out._i -= a; return out; } 1412 1413 size_t operator-(const _Self& other) const { return _i - other._i; } 1414 1415 bool operator==(const _Self& other) const { 1416 assert(_addressSpace == other._addressSpace); 1417 assert(_sects == other._sects); 1418 return _i == other._i; 1419 } 1420 1421 bool operator!=(const _Self& other) const { 1422 assert(_addressSpace == other._addressSpace); 1423 assert(_sects == other._sects); 1424 return _i != other._i; 1425 } 1426 1427 typename A::pint_t operator*() const { return functionAddress(); } 1428 1429 typename A::pint_t functionAddress() const { 1430 typename A::pint_t indexAddr = _sects->arm_section + arrayoffsetof( 1431 EHABIIndexEntry, _i, functionOffset); 1432 return indexAddr + signExtendPrel31(_addressSpace->get32(indexAddr)); 1433 } 1434 1435 typename A::pint_t dataAddress() { 1436 typename A::pint_t indexAddr = _sects->arm_section + arrayoffsetof( 1437 EHABIIndexEntry, _i, data); 1438 return indexAddr; 1439 } 1440 1441 private: 1442 size_t _i; 1443 A* _addressSpace; 1444 const UnwindInfoSections* _sects; 1445 }; 1446 1447 namespace { 1448 1449 template <typename A> 1450 EHABISectionIterator<A> EHABISectionUpperBound( 1451 EHABISectionIterator<A> first, 1452 EHABISectionIterator<A> last, 1453 typename A::pint_t value) { 1454 size_t len = last - first; 1455 while (len > 0) { 1456 size_t l2 = len / 2; 1457 EHABISectionIterator<A> m = first + l2; 1458 if (value < *m) { 1459 len = l2; 1460 } else { 1461 first = ++m; 1462 len -= l2 + 1; 1463 } 1464 } 1465 return first; 1466 } 1467 1468 } 1469 1470 template <typename A, typename R> 1471 bool UnwindCursor<A, R>::getInfoFromEHABISection( 1472 pint_t pc, 1473 const UnwindInfoSections §s) { 1474 EHABISectionIterator<A> begin = 1475 EHABISectionIterator<A>::begin(_addressSpace, sects); 1476 EHABISectionIterator<A> end = 1477 EHABISectionIterator<A>::end(_addressSpace, sects); 1478 if (begin == end) 1479 return false; 1480 1481 EHABISectionIterator<A> itNextPC = EHABISectionUpperBound(begin, end, pc); 1482 if (itNextPC == begin) 1483 return false; 1484 EHABISectionIterator<A> itThisPC = itNextPC - 1; 1485 1486 pint_t thisPC = itThisPC.functionAddress(); 1487 // If an exception is thrown from a function, corresponding to the last entry 1488 // in the table, we don't really know the function extent and have to choose a 1489 // value for nextPC. Choosing max() will allow the range check during trace to 1490 // succeed. 1491 pint_t nextPC = (itNextPC == end) ? UINTPTR_MAX : itNextPC.functionAddress(); 1492 pint_t indexDataAddr = itThisPC.dataAddress(); 1493 1494 if (indexDataAddr == 0) 1495 return false; 1496 1497 uint32_t indexData = _addressSpace.get32(indexDataAddr); 1498 if (indexData == UNW_EXIDX_CANTUNWIND) 1499 return false; 1500 1501 // If the high bit is set, the exception handling table entry is inline inside 1502 // the index table entry on the second word (aka |indexDataAddr|). Otherwise, 1503 // the table points at an offset in the exception handling table (section 5 1504 // EHABI). 1505 pint_t exceptionTableAddr; 1506 uint32_t exceptionTableData; 1507 bool isSingleWordEHT; 1508 if (indexData & 0x80000000) { 1509 exceptionTableAddr = indexDataAddr; 1510 // TODO(ajwong): Should this data be 0? 1511 exceptionTableData = indexData; 1512 isSingleWordEHT = true; 1513 } else { 1514 exceptionTableAddr = indexDataAddr + signExtendPrel31(indexData); 1515 exceptionTableData = _addressSpace.get32(exceptionTableAddr); 1516 isSingleWordEHT = false; 1517 } 1518 1519 // Now we know the 3 things: 1520 // exceptionTableAddr -- exception handler table entry. 1521 // exceptionTableData -- the data inside the first word of the eht entry. 1522 // isSingleWordEHT -- whether the entry is in the index. 1523 unw_word_t personalityRoutine = 0xbadf00d; 1524 bool scope32 = false; 1525 uintptr_t lsda; 1526 1527 // If the high bit in the exception handling table entry is set, the entry is 1528 // in compact form (section 6.3 EHABI). 1529 if (exceptionTableData & 0x80000000) { 1530 // Grab the index of the personality routine from the compact form. 1531 uint32_t choice = (exceptionTableData & 0x0f000000) >> 24; 1532 uint32_t extraWords = 0; 1533 switch (choice) { 1534 case 0: 1535 personalityRoutine = (unw_word_t) &__aeabi_unwind_cpp_pr0; 1536 extraWords = 0; 1537 scope32 = false; 1538 lsda = isSingleWordEHT ? 0 : (exceptionTableAddr + 4); 1539 break; 1540 case 1: 1541 personalityRoutine = (unw_word_t) &__aeabi_unwind_cpp_pr1; 1542 extraWords = (exceptionTableData & 0x00ff0000) >> 16; 1543 scope32 = false; 1544 lsda = exceptionTableAddr + (extraWords + 1) * 4; 1545 break; 1546 case 2: 1547 personalityRoutine = (unw_word_t) &__aeabi_unwind_cpp_pr2; 1548 extraWords = (exceptionTableData & 0x00ff0000) >> 16; 1549 scope32 = true; 1550 lsda = exceptionTableAddr + (extraWords + 1) * 4; 1551 break; 1552 default: 1553 _LIBUNWIND_ABORT("unknown personality routine"); 1554 return false; 1555 } 1556 1557 if (isSingleWordEHT) { 1558 if (extraWords != 0) { 1559 _LIBUNWIND_ABORT("index inlined table detected but pr function " 1560 "requires extra words"); 1561 return false; 1562 } 1563 } 1564 } else { 1565 pint_t personalityAddr = 1566 exceptionTableAddr + signExtendPrel31(exceptionTableData); 1567 personalityRoutine = personalityAddr; 1568 1569 // ARM EHABI # 6.2, # 9.2 1570 // 1571 // +---- ehtp 1572 // v 1573 // +--------------------------------------+ 1574 // | +--------+--------+--------+-------+ | 1575 // | |0| prel31 to personalityRoutine | | 1576 // | +--------+--------+--------+-------+ | 1577 // | | N | unwind opcodes | | <-- UnwindData 1578 // | +--------+--------+--------+-------+ | 1579 // | | Word 2 unwind opcodes | | 1580 // | +--------+--------+--------+-------+ | 1581 // | ... | 1582 // | +--------+--------+--------+-------+ | 1583 // | | Word N unwind opcodes | | 1584 // | +--------+--------+--------+-------+ | 1585 // | | LSDA | | <-- lsda 1586 // | | ... | | 1587 // | +--------+--------+--------+-------+ | 1588 // +--------------------------------------+ 1589 1590 uint32_t *UnwindData = reinterpret_cast<uint32_t*>(exceptionTableAddr) + 1; 1591 uint32_t FirstDataWord = *UnwindData; 1592 size_t N = ((FirstDataWord >> 24) & 0xff); 1593 size_t NDataWords = N + 1; 1594 lsda = reinterpret_cast<uintptr_t>(UnwindData + NDataWords); 1595 } 1596 1597 _info.start_ip = thisPC; 1598 _info.end_ip = nextPC; 1599 _info.handler = personalityRoutine; 1600 _info.unwind_info = exceptionTableAddr; 1601 _info.lsda = lsda; 1602 // flags is pr_cache.additional. See EHABI #7.2 for definition of bit 0. 1603 _info.flags = (isSingleWordEHT ? 1 : 0) | (scope32 ? 0x2 : 0); // Use enum? 1604 1605 return true; 1606 } 1607 #endif 1608 1609 #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 1610 template <typename A, typename R> 1611 bool UnwindCursor<A, R>::getInfoFromFdeCie( 1612 const typename CFI_Parser<A>::FDE_Info &fdeInfo, 1613 const typename CFI_Parser<A>::CIE_Info &cieInfo, pint_t pc, 1614 uintptr_t dso_base) { 1615 typename CFI_Parser<A>::PrologInfo prolog; 1616 if (CFI_Parser<A>::parseFDEInstructions(_addressSpace, fdeInfo, cieInfo, pc, 1617 R::getArch(), &prolog)) { 1618 // Save off parsed FDE info 1619 _info.start_ip = fdeInfo.pcStart; 1620 _info.end_ip = fdeInfo.pcEnd; 1621 _info.lsda = fdeInfo.lsda; 1622 _info.handler = cieInfo.personality; 1623 // Some frameless functions need SP altered when resuming in function, so 1624 // propagate spExtraArgSize. 1625 _info.gp = prolog.spExtraArgSize; 1626 _info.flags = 0; 1627 _info.format = dwarfEncoding(); 1628 _info.unwind_info = fdeInfo.fdeStart; 1629 _info.unwind_info_size = static_cast<uint32_t>(fdeInfo.fdeLength); 1630 _info.extra = static_cast<unw_word_t>(dso_base); 1631 return true; 1632 } 1633 return false; 1634 } 1635 1636 template <typename A, typename R> 1637 bool UnwindCursor<A, R>::getInfoFromDwarfSection(pint_t pc, 1638 const UnwindInfoSections §s, 1639 uint32_t fdeSectionOffsetHint) { 1640 typename CFI_Parser<A>::FDE_Info fdeInfo; 1641 typename CFI_Parser<A>::CIE_Info cieInfo; 1642 bool foundFDE = false; 1643 bool foundInCache = false; 1644 // If compact encoding table gave offset into dwarf section, go directly there 1645 if (fdeSectionOffsetHint != 0) { 1646 foundFDE = CFI_Parser<A>::findFDE(_addressSpace, pc, sects.dwarf_section, 1647 sects.dwarf_section_length, 1648 sects.dwarf_section + fdeSectionOffsetHint, 1649 &fdeInfo, &cieInfo); 1650 } 1651 #if defined(_LIBUNWIND_SUPPORT_DWARF_INDEX) 1652 if (!foundFDE && (sects.dwarf_index_section != 0)) { 1653 foundFDE = EHHeaderParser<A>::findFDE( 1654 _addressSpace, pc, sects.dwarf_index_section, 1655 (uint32_t)sects.dwarf_index_section_length, &fdeInfo, &cieInfo); 1656 } 1657 #endif 1658 if (!foundFDE) { 1659 // otherwise, search cache of previously found FDEs. 1660 pint_t cachedFDE = DwarfFDECache<A>::findFDE(sects.dso_base, pc); 1661 if (cachedFDE != 0) { 1662 foundFDE = 1663 CFI_Parser<A>::findFDE(_addressSpace, pc, sects.dwarf_section, 1664 sects.dwarf_section_length, 1665 cachedFDE, &fdeInfo, &cieInfo); 1666 foundInCache = foundFDE; 1667 } 1668 } 1669 if (!foundFDE) { 1670 // Still not found, do full scan of __eh_frame section. 1671 foundFDE = CFI_Parser<A>::findFDE(_addressSpace, pc, sects.dwarf_section, 1672 sects.dwarf_section_length, 0, 1673 &fdeInfo, &cieInfo); 1674 } 1675 if (foundFDE) { 1676 if (getInfoFromFdeCie(fdeInfo, cieInfo, pc, sects.dso_base)) { 1677 // Add to cache (to make next lookup faster) if we had no hint 1678 // and there was no index. 1679 if (!foundInCache && (fdeSectionOffsetHint == 0)) { 1680 #if defined(_LIBUNWIND_SUPPORT_DWARF_INDEX) 1681 if (sects.dwarf_index_section == 0) 1682 #endif 1683 DwarfFDECache<A>::add(sects.dso_base, fdeInfo.pcStart, fdeInfo.pcEnd, 1684 fdeInfo.fdeStart); 1685 } 1686 return true; 1687 } 1688 } 1689 //_LIBUNWIND_DEBUG_LOG("can't find/use FDE for pc=0x%llX", (uint64_t)pc); 1690 return false; 1691 } 1692 #endif // defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 1693 1694 1695 #if defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND) 1696 template <typename A, typename R> 1697 bool UnwindCursor<A, R>::getInfoFromCompactEncodingSection(pint_t pc, 1698 const UnwindInfoSections §s) { 1699 const bool log = false; 1700 if (log) 1701 fprintf(stderr, "getInfoFromCompactEncodingSection(pc=0x%llX, mh=0x%llX)\n", 1702 (uint64_t)pc, (uint64_t)sects.dso_base); 1703 1704 const UnwindSectionHeader<A> sectionHeader(_addressSpace, 1705 sects.compact_unwind_section); 1706 if (sectionHeader.version() != UNWIND_SECTION_VERSION) 1707 return false; 1708 1709 // do a binary search of top level index to find page with unwind info 1710 pint_t targetFunctionOffset = pc - sects.dso_base; 1711 const UnwindSectionIndexArray<A> topIndex(_addressSpace, 1712 sects.compact_unwind_section 1713 + sectionHeader.indexSectionOffset()); 1714 uint32_t low = 0; 1715 uint32_t high = sectionHeader.indexCount(); 1716 uint32_t last = high - 1; 1717 while (low < high) { 1718 uint32_t mid = (low + high) / 2; 1719 //if ( log ) fprintf(stderr, "\tmid=%d, low=%d, high=%d, *mid=0x%08X\n", 1720 //mid, low, high, topIndex.functionOffset(mid)); 1721 if (topIndex.functionOffset(mid) <= targetFunctionOffset) { 1722 if ((mid == last) || 1723 (topIndex.functionOffset(mid + 1) > targetFunctionOffset)) { 1724 low = mid; 1725 break; 1726 } else { 1727 low = mid + 1; 1728 } 1729 } else { 1730 high = mid; 1731 } 1732 } 1733 const uint32_t firstLevelFunctionOffset = topIndex.functionOffset(low); 1734 const uint32_t firstLevelNextPageFunctionOffset = 1735 topIndex.functionOffset(low + 1); 1736 const pint_t secondLevelAddr = 1737 sects.compact_unwind_section + topIndex.secondLevelPagesSectionOffset(low); 1738 const pint_t lsdaArrayStartAddr = 1739 sects.compact_unwind_section + topIndex.lsdaIndexArraySectionOffset(low); 1740 const pint_t lsdaArrayEndAddr = 1741 sects.compact_unwind_section + topIndex.lsdaIndexArraySectionOffset(low+1); 1742 if (log) 1743 fprintf(stderr, "\tfirst level search for result index=%d " 1744 "to secondLevelAddr=0x%llX\n", 1745 low, (uint64_t) secondLevelAddr); 1746 // do a binary search of second level page index 1747 uint32_t encoding = 0; 1748 pint_t funcStart = 0; 1749 pint_t funcEnd = 0; 1750 pint_t lsda = 0; 1751 pint_t personality = 0; 1752 uint32_t pageKind = _addressSpace.get32(secondLevelAddr); 1753 if (pageKind == UNWIND_SECOND_LEVEL_REGULAR) { 1754 // regular page 1755 UnwindSectionRegularPageHeader<A> pageHeader(_addressSpace, 1756 secondLevelAddr); 1757 UnwindSectionRegularArray<A> pageIndex( 1758 _addressSpace, secondLevelAddr + pageHeader.entryPageOffset()); 1759 // binary search looks for entry with e where index[e].offset <= pc < 1760 // index[e+1].offset 1761 if (log) 1762 fprintf(stderr, "\tbinary search for targetFunctionOffset=0x%08llX in " 1763 "regular page starting at secondLevelAddr=0x%llX\n", 1764 (uint64_t) targetFunctionOffset, (uint64_t) secondLevelAddr); 1765 low = 0; 1766 high = pageHeader.entryCount(); 1767 while (low < high) { 1768 uint32_t mid = (low + high) / 2; 1769 if (pageIndex.functionOffset(mid) <= targetFunctionOffset) { 1770 if (mid == (uint32_t)(pageHeader.entryCount() - 1)) { 1771 // at end of table 1772 low = mid; 1773 funcEnd = firstLevelNextPageFunctionOffset + sects.dso_base; 1774 break; 1775 } else if (pageIndex.functionOffset(mid + 1) > targetFunctionOffset) { 1776 // next is too big, so we found it 1777 low = mid; 1778 funcEnd = pageIndex.functionOffset(low + 1) + sects.dso_base; 1779 break; 1780 } else { 1781 low = mid + 1; 1782 } 1783 } else { 1784 high = mid; 1785 } 1786 } 1787 encoding = pageIndex.encoding(low); 1788 funcStart = pageIndex.functionOffset(low) + sects.dso_base; 1789 if (pc < funcStart) { 1790 if (log) 1791 fprintf( 1792 stderr, 1793 "\tpc not in table, pc=0x%llX, funcStart=0x%llX, funcEnd=0x%llX\n", 1794 (uint64_t) pc, (uint64_t) funcStart, (uint64_t) funcEnd); 1795 return false; 1796 } 1797 if (pc > funcEnd) { 1798 if (log) 1799 fprintf( 1800 stderr, 1801 "\tpc not in table, pc=0x%llX, funcStart=0x%llX, funcEnd=0x%llX\n", 1802 (uint64_t) pc, (uint64_t) funcStart, (uint64_t) funcEnd); 1803 return false; 1804 } 1805 } else if (pageKind == UNWIND_SECOND_LEVEL_COMPRESSED) { 1806 // compressed page 1807 UnwindSectionCompressedPageHeader<A> pageHeader(_addressSpace, 1808 secondLevelAddr); 1809 UnwindSectionCompressedArray<A> pageIndex( 1810 _addressSpace, secondLevelAddr + pageHeader.entryPageOffset()); 1811 const uint32_t targetFunctionPageOffset = 1812 (uint32_t)(targetFunctionOffset - firstLevelFunctionOffset); 1813 // binary search looks for entry with e where index[e].offset <= pc < 1814 // index[e+1].offset 1815 if (log) 1816 fprintf(stderr, "\tbinary search of compressed page starting at " 1817 "secondLevelAddr=0x%llX\n", 1818 (uint64_t) secondLevelAddr); 1819 low = 0; 1820 last = pageHeader.entryCount() - 1; 1821 high = pageHeader.entryCount(); 1822 while (low < high) { 1823 uint32_t mid = (low + high) / 2; 1824 if (pageIndex.functionOffset(mid) <= targetFunctionPageOffset) { 1825 if ((mid == last) || 1826 (pageIndex.functionOffset(mid + 1) > targetFunctionPageOffset)) { 1827 low = mid; 1828 break; 1829 } else { 1830 low = mid + 1; 1831 } 1832 } else { 1833 high = mid; 1834 } 1835 } 1836 funcStart = pageIndex.functionOffset(low) + firstLevelFunctionOffset 1837 + sects.dso_base; 1838 if (low < last) 1839 funcEnd = 1840 pageIndex.functionOffset(low + 1) + firstLevelFunctionOffset 1841 + sects.dso_base; 1842 else 1843 funcEnd = firstLevelNextPageFunctionOffset + sects.dso_base; 1844 if (pc < funcStart) { 1845 _LIBUNWIND_DEBUG_LOG("malformed __unwind_info, pc=0x%llX " 1846 "not in second level compressed unwind table. " 1847 "funcStart=0x%llX", 1848 (uint64_t) pc, (uint64_t) funcStart); 1849 return false; 1850 } 1851 if (pc > funcEnd) { 1852 _LIBUNWIND_DEBUG_LOG("malformed __unwind_info, pc=0x%llX " 1853 "not in second level compressed unwind table. " 1854 "funcEnd=0x%llX", 1855 (uint64_t) pc, (uint64_t) funcEnd); 1856 return false; 1857 } 1858 uint16_t encodingIndex = pageIndex.encodingIndex(low); 1859 if (encodingIndex < sectionHeader.commonEncodingsArrayCount()) { 1860 // encoding is in common table in section header 1861 encoding = _addressSpace.get32( 1862 sects.compact_unwind_section + 1863 sectionHeader.commonEncodingsArraySectionOffset() + 1864 encodingIndex * sizeof(uint32_t)); 1865 } else { 1866 // encoding is in page specific table 1867 uint16_t pageEncodingIndex = 1868 encodingIndex - (uint16_t)sectionHeader.commonEncodingsArrayCount(); 1869 encoding = _addressSpace.get32(secondLevelAddr + 1870 pageHeader.encodingsPageOffset() + 1871 pageEncodingIndex * sizeof(uint32_t)); 1872 } 1873 } else { 1874 _LIBUNWIND_DEBUG_LOG( 1875 "malformed __unwind_info at 0x%0llX bad second level page", 1876 (uint64_t)sects.compact_unwind_section); 1877 return false; 1878 } 1879 1880 // look up LSDA, if encoding says function has one 1881 if (encoding & UNWIND_HAS_LSDA) { 1882 UnwindSectionLsdaArray<A> lsdaIndex(_addressSpace, lsdaArrayStartAddr); 1883 uint32_t funcStartOffset = (uint32_t)(funcStart - sects.dso_base); 1884 low = 0; 1885 high = (uint32_t)(lsdaArrayEndAddr - lsdaArrayStartAddr) / 1886 sizeof(unwind_info_section_header_lsda_index_entry); 1887 // binary search looks for entry with exact match for functionOffset 1888 if (log) 1889 fprintf(stderr, 1890 "\tbinary search of lsda table for targetFunctionOffset=0x%08X\n", 1891 funcStartOffset); 1892 while (low < high) { 1893 uint32_t mid = (low + high) / 2; 1894 if (lsdaIndex.functionOffset(mid) == funcStartOffset) { 1895 lsda = lsdaIndex.lsdaOffset(mid) + sects.dso_base; 1896 break; 1897 } else if (lsdaIndex.functionOffset(mid) < funcStartOffset) { 1898 low = mid + 1; 1899 } else { 1900 high = mid; 1901 } 1902 } 1903 if (lsda == 0) { 1904 _LIBUNWIND_DEBUG_LOG("found encoding 0x%08X with HAS_LSDA bit set for " 1905 "pc=0x%0llX, but lsda table has no entry", 1906 encoding, (uint64_t) pc); 1907 return false; 1908 } 1909 } 1910 1911 // extract personality routine, if encoding says function has one 1912 uint32_t personalityIndex = (encoding & UNWIND_PERSONALITY_MASK) >> 1913 (__builtin_ctz(UNWIND_PERSONALITY_MASK)); 1914 if (personalityIndex != 0) { 1915 --personalityIndex; // change 1-based to zero-based index 1916 if (personalityIndex >= sectionHeader.personalityArrayCount()) { 1917 _LIBUNWIND_DEBUG_LOG("found encoding 0x%08X with personality index %d, " 1918 "but personality table has only %d entries", 1919 encoding, personalityIndex, 1920 sectionHeader.personalityArrayCount()); 1921 return false; 1922 } 1923 int32_t personalityDelta = (int32_t)_addressSpace.get32( 1924 sects.compact_unwind_section + 1925 sectionHeader.personalityArraySectionOffset() + 1926 personalityIndex * sizeof(uint32_t)); 1927 pint_t personalityPointer = sects.dso_base + (pint_t)personalityDelta; 1928 personality = _addressSpace.getP(personalityPointer); 1929 if (log) 1930 fprintf(stderr, "getInfoFromCompactEncodingSection(pc=0x%llX), " 1931 "personalityDelta=0x%08X, personality=0x%08llX\n", 1932 (uint64_t) pc, personalityDelta, (uint64_t) personality); 1933 } 1934 1935 if (log) 1936 fprintf(stderr, "getInfoFromCompactEncodingSection(pc=0x%llX), " 1937 "encoding=0x%08X, lsda=0x%08llX for funcStart=0x%llX\n", 1938 (uint64_t) pc, encoding, (uint64_t) lsda, (uint64_t) funcStart); 1939 _info.start_ip = funcStart; 1940 _info.end_ip = funcEnd; 1941 _info.lsda = lsda; 1942 _info.handler = personality; 1943 _info.gp = 0; 1944 _info.flags = 0; 1945 _info.format = encoding; 1946 _info.unwind_info = 0; 1947 _info.unwind_info_size = 0; 1948 _info.extra = sects.dso_base; 1949 return true; 1950 } 1951 #endif // defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND) 1952 1953 1954 #if defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) 1955 template <typename A, typename R> 1956 bool UnwindCursor<A, R>::getInfoFromSEH(pint_t pc) { 1957 pint_t base; 1958 RUNTIME_FUNCTION *unwindEntry = lookUpSEHUnwindInfo(pc, &base); 1959 if (!unwindEntry) { 1960 _LIBUNWIND_DEBUG_LOG("\tpc not in table, pc=0x%llX", (uint64_t) pc); 1961 return false; 1962 } 1963 _info.gp = 0; 1964 _info.flags = 0; 1965 _info.format = 0; 1966 _info.unwind_info_size = sizeof(RUNTIME_FUNCTION); 1967 _info.unwind_info = reinterpret_cast<unw_word_t>(unwindEntry); 1968 _info.extra = base; 1969 _info.start_ip = base + unwindEntry->BeginAddress; 1970 #ifdef _LIBUNWIND_TARGET_X86_64 1971 _info.end_ip = base + unwindEntry->EndAddress; 1972 // Only fill in the handler and LSDA if they're stale. 1973 if (pc != getLastPC()) { 1974 UNWIND_INFO *xdata = reinterpret_cast<UNWIND_INFO *>(base + unwindEntry->UnwindData); 1975 if (xdata->Flags & (UNW_FLAG_EHANDLER|UNW_FLAG_UHANDLER)) { 1976 // The personality is given in the UNWIND_INFO itself. The LSDA immediately 1977 // follows the UNWIND_INFO. (This follows how both Clang and MSVC emit 1978 // these structures.) 1979 // N.B. UNWIND_INFO structs are DWORD-aligned. 1980 uint32_t lastcode = (xdata->CountOfCodes + 1) & ~1; 1981 const uint32_t *handler = reinterpret_cast<uint32_t *>(&xdata->UnwindCodes[lastcode]); 1982 _info.lsda = reinterpret_cast<unw_word_t>(handler+1); 1983 if (*handler) { 1984 _info.handler = reinterpret_cast<unw_word_t>(__libunwind_seh_personality); 1985 } else 1986 _info.handler = 0; 1987 } else { 1988 _info.lsda = 0; 1989 _info.handler = 0; 1990 } 1991 } 1992 #endif 1993 setLastPC(pc); 1994 return true; 1995 } 1996 #endif 1997 1998 #if defined(_LIBUNWIND_SUPPORT_TBTAB_UNWIND) 1999 // Masks for traceback table field xtbtable. 2000 enum xTBTableMask : uint8_t { 2001 reservedBit = 0x02, // The traceback table was incorrectly generated if set 2002 // (see comments in function getInfoFromTBTable(). 2003 ehInfoBit = 0x08 // Exception handling info is present if set 2004 }; 2005 2006 enum frameType : unw_word_t { 2007 frameWithXLEHStateTable = 0, 2008 frameWithEHInfo = 1 2009 }; 2010 2011 extern "C" { 2012 typedef _Unwind_Reason_Code __xlcxx_personality_v0_t(int, _Unwind_Action, 2013 uint64_t, 2014 _Unwind_Exception *, 2015 struct _Unwind_Context *); 2016 __attribute__((__weak__)) __xlcxx_personality_v0_t __xlcxx_personality_v0; 2017 } 2018 2019 static __xlcxx_personality_v0_t *xlcPersonalityV0; 2020 static RWMutex xlcPersonalityV0InitLock; 2021 2022 template <typename A, typename R> 2023 bool UnwindCursor<A, R>::getInfoFromTBTable(pint_t pc, R ®isters) { 2024 uint32_t *p = reinterpret_cast<uint32_t *>(pc); 2025 2026 // Keep looking forward until a word of 0 is found. The traceback 2027 // table starts at the following word. 2028 while (*p) 2029 ++p; 2030 tbtable *TBTable = reinterpret_cast<tbtable *>(p + 1); 2031 2032 if (_LIBUNWIND_TRACING_UNWINDING) { 2033 char functionBuf[512]; 2034 const char *functionName = functionBuf; 2035 unw_word_t offset; 2036 if (!getFunctionName(functionBuf, sizeof(functionBuf), &offset)) { 2037 functionName = ".anonymous."; 2038 } 2039 _LIBUNWIND_TRACE_UNWINDING("%s: Look up traceback table of func=%s at %p", 2040 __func__, functionName, 2041 reinterpret_cast<void *>(TBTable)); 2042 } 2043 2044 // If the traceback table does not contain necessary info, bypass this frame. 2045 if (!TBTable->tb.has_tboff) 2046 return false; 2047 2048 // Structure tbtable_ext contains important data we are looking for. 2049 p = reinterpret_cast<uint32_t *>(&TBTable->tb_ext); 2050 2051 // Skip field parminfo if it exists. 2052 if (TBTable->tb.fixedparms || TBTable->tb.floatparms) 2053 ++p; 2054 2055 // p now points to tb_offset, the offset from start of function to TB table. 2056 unw_word_t start_ip = 2057 reinterpret_cast<unw_word_t>(TBTable) - *p - sizeof(uint32_t); 2058 unw_word_t end_ip = reinterpret_cast<unw_word_t>(TBTable); 2059 ++p; 2060 2061 _LIBUNWIND_TRACE_UNWINDING("start_ip=%p, end_ip=%p\n", 2062 reinterpret_cast<void *>(start_ip), 2063 reinterpret_cast<void *>(end_ip)); 2064 2065 // Skip field hand_mask if it exists. 2066 if (TBTable->tb.int_hndl) 2067 ++p; 2068 2069 unw_word_t lsda = 0; 2070 unw_word_t handler = 0; 2071 unw_word_t flags = frameType::frameWithXLEHStateTable; 2072 2073 if (TBTable->tb.lang == TB_CPLUSPLUS && TBTable->tb.has_ctl) { 2074 // State table info is available. The ctl_info field indicates the 2075 // number of CTL anchors. There should be only one entry for the C++ 2076 // state table. 2077 assert(*p == 1 && "libunwind: there must be only one ctl_info entry"); 2078 ++p; 2079 // p points to the offset of the state table into the stack. 2080 pint_t stateTableOffset = *p++; 2081 2082 int framePointerReg; 2083 2084 // Skip fields name_len and name if exist. 2085 if (TBTable->tb.name_present) { 2086 const uint16_t name_len = *(reinterpret_cast<uint16_t *>(p)); 2087 p = reinterpret_cast<uint32_t *>(reinterpret_cast<char *>(p) + name_len + 2088 sizeof(uint16_t)); 2089 } 2090 2091 if (TBTable->tb.uses_alloca) 2092 framePointerReg = *(reinterpret_cast<char *>(p)); 2093 else 2094 framePointerReg = 1; // default frame pointer == SP 2095 2096 _LIBUNWIND_TRACE_UNWINDING( 2097 "framePointerReg=%d, framePointer=%p, " 2098 "stateTableOffset=%#lx\n", 2099 framePointerReg, 2100 reinterpret_cast<void *>(_registers.getRegister(framePointerReg)), 2101 stateTableOffset); 2102 lsda = _registers.getRegister(framePointerReg) + stateTableOffset; 2103 2104 // Since the traceback table generated by the legacy XLC++ does not 2105 // provide the location of the personality for the state table, 2106 // function __xlcxx_personality_v0(), which is the personality for the state 2107 // table and is exported from libc++abi, is directly assigned as the 2108 // handler here. When a legacy XLC++ frame is encountered, the symbol 2109 // is resolved dynamically using dlopen() to avoid hard dependency from 2110 // libunwind on libc++abi. 2111 2112 // Resolve the function pointer to the state table personality if it has 2113 // not already. 2114 if (xlcPersonalityV0 == NULL) { 2115 xlcPersonalityV0InitLock.lock(); 2116 if (xlcPersonalityV0 == NULL) { 2117 // If libc++abi is statically linked in, symbol __xlcxx_personality_v0 2118 // has been resolved at the link time. 2119 xlcPersonalityV0 = &__xlcxx_personality_v0; 2120 if (xlcPersonalityV0 == NULL) { 2121 // libc++abi is dynamically linked. Resolve __xlcxx_personality_v0 2122 // using dlopen(). 2123 const char libcxxabi[] = "libc++abi.a(libc++abi.so.1)"; 2124 void *libHandle; 2125 // The AIX dlopen() sets errno to 0 when it is successful, which 2126 // clobbers the value of errno from the user code. This is an AIX 2127 // bug because according to POSIX it should not set errno to 0. To 2128 // workaround before AIX fixes the bug, errno is saved and restored. 2129 int saveErrno = errno; 2130 libHandle = dlopen(libcxxabi, RTLD_MEMBER | RTLD_NOW); 2131 if (libHandle == NULL) { 2132 _LIBUNWIND_TRACE_UNWINDING("dlopen() failed with errno=%d\n", 2133 errno); 2134 assert(0 && "dlopen() failed"); 2135 } 2136 xlcPersonalityV0 = reinterpret_cast<__xlcxx_personality_v0_t *>( 2137 dlsym(libHandle, "__xlcxx_personality_v0")); 2138 if (xlcPersonalityV0 == NULL) { 2139 _LIBUNWIND_TRACE_UNWINDING("dlsym() failed with errno=%d\n", errno); 2140 assert(0 && "dlsym() failed"); 2141 } 2142 dlclose(libHandle); 2143 errno = saveErrno; 2144 } 2145 } 2146 xlcPersonalityV0InitLock.unlock(); 2147 } 2148 handler = reinterpret_cast<unw_word_t>(xlcPersonalityV0); 2149 _LIBUNWIND_TRACE_UNWINDING("State table: LSDA=%p, Personality=%p\n", 2150 reinterpret_cast<void *>(lsda), 2151 reinterpret_cast<void *>(handler)); 2152 } else if (TBTable->tb.longtbtable) { 2153 // This frame has the traceback table extension. Possible cases are 2154 // 1) a C++ frame that has the 'eh_info' structure; 2) a C++ frame that 2155 // is not EH aware; or, 3) a frame of other languages. We need to figure out 2156 // if the traceback table extension contains the 'eh_info' structure. 2157 // 2158 // We also need to deal with the complexity arising from some XL compiler 2159 // versions use the wrong ordering of 'longtbtable' and 'has_vec' bits 2160 // where the 'longtbtable' bit is meant to be the 'has_vec' bit and vice 2161 // versa. For frames of code generated by those compilers, the 'longtbtable' 2162 // bit may be set but there isn't really a traceback table extension. 2163 // 2164 // In </usr/include/sys/debug.h>, there is the following definition of 2165 // 'struct tbtable_ext'. It is not really a structure but a dummy to 2166 // collect the description of optional parts of the traceback table. 2167 // 2168 // struct tbtable_ext { 2169 // ... 2170 // char alloca_reg; /* Register for alloca automatic storage */ 2171 // struct vec_ext vec_ext; /* Vector extension (if has_vec is set) */ 2172 // unsigned char xtbtable; /* More tbtable fields, if longtbtable is set*/ 2173 // }; 2174 // 2175 // Depending on how the 'has_vec'/'longtbtable' bit is interpreted, the data 2176 // following 'alloca_reg' can be treated either as 'struct vec_ext' or 2177 // 'unsigned char xtbtable'. 'xtbtable' bits are defined in 2178 // </usr/include/sys/debug.h> as flags. The 7th bit '0x02' is currently 2179 // unused and should not be set. 'struct vec_ext' is defined in 2180 // </usr/include/sys/debug.h> as follows: 2181 // 2182 // struct vec_ext { 2183 // unsigned vr_saved:6; /* Number of non-volatile vector regs saved 2184 // */ 2185 // /* first register saved is assumed to be */ 2186 // /* 32 - vr_saved */ 2187 // unsigned saves_vrsave:1; /* Set if vrsave is saved on the stack */ 2188 // unsigned has_varargs:1; 2189 // ... 2190 // }; 2191 // 2192 // Here, the 7th bit is used as 'saves_vrsave'. To determine whether it 2193 // is 'struct vec_ext' or 'xtbtable' that follows 'alloca_reg', 2194 // we checks if the 7th bit is set or not because 'xtbtable' should 2195 // never have the 7th bit set. The 7th bit of 'xtbtable' will be reserved 2196 // in the future to make sure the mitigation works. This mitigation 2197 // is not 100% bullet proof because 'struct vec_ext' may not always have 2198 // 'saves_vrsave' bit set. 2199 // 2200 // 'reservedBit' is defined in enum 'xTBTableMask' above as the mask for 2201 // checking the 7th bit. 2202 2203 // p points to field name len. 2204 uint8_t *charPtr = reinterpret_cast<uint8_t *>(p); 2205 2206 // Skip fields name_len and name if they exist. 2207 if (TBTable->tb.name_present) { 2208 const uint16_t name_len = *(reinterpret_cast<uint16_t *>(charPtr)); 2209 charPtr = charPtr + name_len + sizeof(uint16_t); 2210 } 2211 2212 // Skip field alloc_reg if it exists. 2213 if (TBTable->tb.uses_alloca) 2214 ++charPtr; 2215 2216 // Check traceback table bit has_vec. Skip struct vec_ext if it exists. 2217 if (TBTable->tb.has_vec) 2218 // Note struct vec_ext does exist at this point because whether the 2219 // ordering of longtbtable and has_vec bits is correct or not, both 2220 // are set. 2221 charPtr += sizeof(struct vec_ext); 2222 2223 // charPtr points to field 'xtbtable'. Check if the EH info is available. 2224 // Also check if the reserved bit of the extended traceback table field 2225 // 'xtbtable' is set. If it is, the traceback table was incorrectly 2226 // generated by an XL compiler that uses the wrong ordering of 'longtbtable' 2227 // and 'has_vec' bits and this is in fact 'struct vec_ext'. So skip the 2228 // frame. 2229 if ((*charPtr & xTBTableMask::ehInfoBit) && 2230 !(*charPtr & xTBTableMask::reservedBit)) { 2231 // Mark this frame has the new EH info. 2232 flags = frameType::frameWithEHInfo; 2233 2234 // eh_info is available. 2235 charPtr++; 2236 // The pointer is 4-byte aligned. 2237 if (reinterpret_cast<uintptr_t>(charPtr) % 4) 2238 charPtr += 4 - reinterpret_cast<uintptr_t>(charPtr) % 4; 2239 uintptr_t *ehInfo = 2240 reinterpret_cast<uintptr_t *>(*(reinterpret_cast<uintptr_t *>( 2241 registers.getRegister(2) + 2242 *(reinterpret_cast<uintptr_t *>(charPtr))))); 2243 2244 // ehInfo points to structure en_info. The first member is version. 2245 // Only version 0 is currently supported. 2246 assert(*(reinterpret_cast<uint32_t *>(ehInfo)) == 0 && 2247 "libunwind: ehInfo version other than 0 is not supported"); 2248 2249 // Increment ehInfo to point to member lsda. 2250 ++ehInfo; 2251 lsda = *ehInfo++; 2252 2253 // enInfo now points to member personality. 2254 handler = *ehInfo; 2255 2256 _LIBUNWIND_TRACE_UNWINDING("Range table: LSDA=%#lx, Personality=%#lx\n", 2257 lsda, handler); 2258 } 2259 } 2260 2261 _info.start_ip = start_ip; 2262 _info.end_ip = end_ip; 2263 _info.lsda = lsda; 2264 _info.handler = handler; 2265 _info.gp = 0; 2266 _info.flags = flags; 2267 _info.format = 0; 2268 _info.unwind_info = reinterpret_cast<unw_word_t>(TBTable); 2269 _info.unwind_info_size = 0; 2270 _info.extra = registers.getRegister(2); 2271 2272 return true; 2273 } 2274 2275 // Step back up the stack following the frame back link. 2276 template <typename A, typename R> 2277 int UnwindCursor<A, R>::stepWithTBTable(pint_t pc, tbtable *TBTable, 2278 R ®isters, bool &isSignalFrame) { 2279 if (_LIBUNWIND_TRACING_UNWINDING) { 2280 char functionBuf[512]; 2281 const char *functionName = functionBuf; 2282 unw_word_t offset; 2283 if (!getFunctionName(functionBuf, sizeof(functionBuf), &offset)) { 2284 functionName = ".anonymous."; 2285 } 2286 _LIBUNWIND_TRACE_UNWINDING("%s: Look up traceback table of func=%s at %p", 2287 __func__, functionName, 2288 reinterpret_cast<void *>(TBTable)); 2289 } 2290 2291 #if defined(__powerpc64__) 2292 // Instruction to reload TOC register "l r2,40(r1)" 2293 const uint32_t loadTOCRegInst = 0xe8410028; 2294 const int32_t unwPPCF0Index = UNW_PPC64_F0; 2295 const int32_t unwPPCV0Index = UNW_PPC64_V0; 2296 #else 2297 // Instruction to reload TOC register "l r2,20(r1)" 2298 const uint32_t loadTOCRegInst = 0x80410014; 2299 const int32_t unwPPCF0Index = UNW_PPC_F0; 2300 const int32_t unwPPCV0Index = UNW_PPC_V0; 2301 #endif 2302 2303 R newRegisters = registers; 2304 2305 // lastStack points to the stack frame of the next routine up. 2306 pint_t lastStack = *(reinterpret_cast<pint_t *>(registers.getSP())); 2307 2308 // Return address is the address after call site instruction. 2309 pint_t returnAddress; 2310 2311 if (isSignalFrame) { 2312 _LIBUNWIND_TRACE_UNWINDING("Possible signal handler frame: lastStack=%p", 2313 reinterpret_cast<void *>(lastStack)); 2314 2315 sigcontext *sigContext = reinterpret_cast<sigcontext *>( 2316 reinterpret_cast<char *>(lastStack) + STKMIN); 2317 returnAddress = sigContext->sc_jmpbuf.jmp_context.iar; 2318 2319 _LIBUNWIND_TRACE_UNWINDING("From sigContext=%p, returnAddress=%p\n", 2320 reinterpret_cast<void *>(sigContext), 2321 reinterpret_cast<void *>(returnAddress)); 2322 2323 if (returnAddress < 0x10000000) { 2324 // Try again using STKMINALIGN 2325 sigContext = reinterpret_cast<sigcontext *>( 2326 reinterpret_cast<char *>(lastStack) + STKMINALIGN); 2327 returnAddress = sigContext->sc_jmpbuf.jmp_context.iar; 2328 if (returnAddress < 0x10000000) { 2329 _LIBUNWIND_TRACE_UNWINDING("Bad returnAddress=%p\n", 2330 reinterpret_cast<void *>(returnAddress)); 2331 return UNW_EBADFRAME; 2332 } else { 2333 _LIBUNWIND_TRACE_UNWINDING("Tried again using STKMINALIGN: " 2334 "sigContext=%p, returnAddress=%p. " 2335 "Seems to be a valid address\n", 2336 reinterpret_cast<void *>(sigContext), 2337 reinterpret_cast<void *>(returnAddress)); 2338 } 2339 } 2340 // Restore the condition register from sigcontext. 2341 newRegisters.setCR(sigContext->sc_jmpbuf.jmp_context.cr); 2342 2343 // Restore GPRs from sigcontext. 2344 for (int i = 0; i < 32; ++i) 2345 newRegisters.setRegister(i, sigContext->sc_jmpbuf.jmp_context.gpr[i]); 2346 2347 // Restore FPRs from sigcontext. 2348 for (int i = 0; i < 32; ++i) 2349 newRegisters.setFloatRegister(i + unwPPCF0Index, 2350 sigContext->sc_jmpbuf.jmp_context.fpr[i]); 2351 2352 // Restore vector registers if there is an associated extended context 2353 // structure. 2354 if (sigContext->sc_jmpbuf.jmp_context.msr & __EXTCTX) { 2355 ucontext_t *uContext = reinterpret_cast<ucontext_t *>(sigContext); 2356 if (uContext->__extctx->__extctx_magic == __EXTCTX_MAGIC) { 2357 for (int i = 0; i < 32; ++i) 2358 newRegisters.setVectorRegister( 2359 i + unwPPCV0Index, *(reinterpret_cast<v128 *>( 2360 &(uContext->__extctx->__vmx.__vr[i])))); 2361 } 2362 } 2363 } else { 2364 // Step up a normal frame. 2365 returnAddress = reinterpret_cast<pint_t *>(lastStack)[2]; 2366 2367 _LIBUNWIND_TRACE_UNWINDING("Extract info from lastStack=%p, " 2368 "returnAddress=%p\n", 2369 reinterpret_cast<void *>(lastStack), 2370 reinterpret_cast<void *>(returnAddress)); 2371 _LIBUNWIND_TRACE_UNWINDING("fpr_regs=%d, gpr_regs=%d, saves_cr=%d\n", 2372 TBTable->tb.fpr_saved, TBTable->tb.gpr_saved, 2373 TBTable->tb.saves_cr); 2374 2375 // Restore FP registers. 2376 char *ptrToRegs = reinterpret_cast<char *>(lastStack); 2377 double *FPRegs = reinterpret_cast<double *>( 2378 ptrToRegs - (TBTable->tb.fpr_saved * sizeof(double))); 2379 for (int i = 0; i < TBTable->tb.fpr_saved; ++i) 2380 newRegisters.setFloatRegister( 2381 32 - TBTable->tb.fpr_saved + i + unwPPCF0Index, FPRegs[i]); 2382 2383 // Restore GP registers. 2384 ptrToRegs = reinterpret_cast<char *>(FPRegs); 2385 uintptr_t *GPRegs = reinterpret_cast<uintptr_t *>( 2386 ptrToRegs - (TBTable->tb.gpr_saved * sizeof(uintptr_t))); 2387 for (int i = 0; i < TBTable->tb.gpr_saved; ++i) 2388 newRegisters.setRegister(32 - TBTable->tb.gpr_saved + i, GPRegs[i]); 2389 2390 // Restore Vector registers. 2391 ptrToRegs = reinterpret_cast<char *>(GPRegs); 2392 2393 // Restore vector registers only if this is a Clang frame. Also 2394 // check if traceback table bit has_vec is set. If it is, structure 2395 // vec_ext is available. 2396 if (_info.flags == frameType::frameWithEHInfo && TBTable->tb.has_vec) { 2397 2398 // Get to the vec_ext structure to check if vector registers are saved. 2399 uint32_t *p = reinterpret_cast<uint32_t *>(&TBTable->tb_ext); 2400 2401 // Skip field parminfo if exists. 2402 if (TBTable->tb.fixedparms || TBTable->tb.floatparms) 2403 ++p; 2404 2405 // Skip field tb_offset if exists. 2406 if (TBTable->tb.has_tboff) 2407 ++p; 2408 2409 // Skip field hand_mask if exists. 2410 if (TBTable->tb.int_hndl) 2411 ++p; 2412 2413 // Skip fields ctl_info and ctl_info_disp if exist. 2414 if (TBTable->tb.has_ctl) { 2415 // Skip field ctl_info. 2416 ++p; 2417 // Skip field ctl_info_disp. 2418 ++p; 2419 } 2420 2421 // Skip fields name_len and name if exist. 2422 // p is supposed to point to field name_len now. 2423 uint8_t *charPtr = reinterpret_cast<uint8_t *>(p); 2424 if (TBTable->tb.name_present) { 2425 const uint16_t name_len = *(reinterpret_cast<uint16_t *>(charPtr)); 2426 charPtr = charPtr + name_len + sizeof(uint16_t); 2427 } 2428 2429 // Skip field alloc_reg if it exists. 2430 if (TBTable->tb.uses_alloca) 2431 ++charPtr; 2432 2433 struct vec_ext *vec_ext = reinterpret_cast<struct vec_ext *>(charPtr); 2434 2435 _LIBUNWIND_TRACE_UNWINDING("vr_saved=%d\n", vec_ext->vr_saved); 2436 2437 // Restore vector register(s) if saved on the stack. 2438 if (vec_ext->vr_saved) { 2439 // Saved vector registers are 16-byte aligned. 2440 if (reinterpret_cast<uintptr_t>(ptrToRegs) % 16) 2441 ptrToRegs -= reinterpret_cast<uintptr_t>(ptrToRegs) % 16; 2442 v128 *VecRegs = reinterpret_cast<v128 *>(ptrToRegs - vec_ext->vr_saved * 2443 sizeof(v128)); 2444 for (int i = 0; i < vec_ext->vr_saved; ++i) { 2445 newRegisters.setVectorRegister( 2446 32 - vec_ext->vr_saved + i + unwPPCV0Index, VecRegs[i]); 2447 } 2448 } 2449 } 2450 if (TBTable->tb.saves_cr) { 2451 // Get the saved condition register. The condition register is only 2452 // a single word. 2453 newRegisters.setCR( 2454 *(reinterpret_cast<uint32_t *>(lastStack + sizeof(uintptr_t)))); 2455 } 2456 2457 // Restore the SP. 2458 newRegisters.setSP(lastStack); 2459 2460 // The first instruction after return. 2461 uint32_t firstInstruction = *(reinterpret_cast<uint32_t *>(returnAddress)); 2462 2463 // Do we need to set the TOC register? 2464 _LIBUNWIND_TRACE_UNWINDING( 2465 "Current gpr2=%p\n", 2466 reinterpret_cast<void *>(newRegisters.getRegister(2))); 2467 if (firstInstruction == loadTOCRegInst) { 2468 _LIBUNWIND_TRACE_UNWINDING( 2469 "Set gpr2=%p from frame\n", 2470 reinterpret_cast<void *>(reinterpret_cast<pint_t *>(lastStack)[5])); 2471 newRegisters.setRegister(2, reinterpret_cast<pint_t *>(lastStack)[5]); 2472 } 2473 } 2474 _LIBUNWIND_TRACE_UNWINDING("lastStack=%p, returnAddress=%p, pc=%p\n", 2475 reinterpret_cast<void *>(lastStack), 2476 reinterpret_cast<void *>(returnAddress), 2477 reinterpret_cast<void *>(pc)); 2478 2479 // The return address is the address after call site instruction, so 2480 // setting IP to that simulates a return. 2481 newRegisters.setIP(reinterpret_cast<uintptr_t>(returnAddress)); 2482 2483 // Simulate the step by replacing the register set with the new ones. 2484 registers = newRegisters; 2485 2486 // Check if the next frame is a signal frame. 2487 pint_t nextStack = *(reinterpret_cast<pint_t *>(registers.getSP())); 2488 2489 // Return address is the address after call site instruction. 2490 pint_t nextReturnAddress = reinterpret_cast<pint_t *>(nextStack)[2]; 2491 2492 if (nextReturnAddress > 0x01 && nextReturnAddress < 0x10000) { 2493 _LIBUNWIND_TRACE_UNWINDING("The next is a signal handler frame: " 2494 "nextStack=%p, next return address=%p\n", 2495 reinterpret_cast<void *>(nextStack), 2496 reinterpret_cast<void *>(nextReturnAddress)); 2497 isSignalFrame = true; 2498 } else { 2499 isSignalFrame = false; 2500 } 2501 2502 return UNW_STEP_SUCCESS; 2503 } 2504 #endif // defined(_LIBUNWIND_SUPPORT_TBTAB_UNWIND) 2505 2506 template <typename A, typename R> 2507 void UnwindCursor<A, R>::setInfoBasedOnIPRegister(bool isReturnAddress) { 2508 #if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) 2509 _isSigReturn = false; 2510 #endif 2511 2512 pint_t pc = static_cast<pint_t>(this->getReg(UNW_REG_IP)); 2513 #if defined(_LIBUNWIND_ARM_EHABI) 2514 // Remove the thumb bit so the IP represents the actual instruction address. 2515 // This matches the behaviour of _Unwind_GetIP on arm. 2516 pc &= (pint_t)~0x1; 2517 #endif 2518 2519 // Exit early if at the top of the stack. 2520 if (pc == 0) { 2521 _unwindInfoMissing = true; 2522 return; 2523 } 2524 2525 // If the last line of a function is a "throw" the compiler sometimes 2526 // emits no instructions after the call to __cxa_throw. This means 2527 // the return address is actually the start of the next function. 2528 // To disambiguate this, back up the pc when we know it is a return 2529 // address. 2530 if (isReturnAddress) 2531 #if defined(_AIX) 2532 // PC needs to be a 4-byte aligned address to be able to look for a 2533 // word of 0 that indicates the start of the traceback table at the end 2534 // of a function on AIX. 2535 pc -= 4; 2536 #else 2537 --pc; 2538 #endif 2539 2540 // Ask address space object to find unwind sections for this pc. 2541 UnwindInfoSections sects; 2542 bool have_sects = false; 2543 if (uwis_cache.getUnwindInfoSectionsForPC(pc, sects)) 2544 have_sects = true; 2545 else if (_addressSpace.findUnwindSections(pc, sects)) { 2546 uwis_cache.setUnwindInfoSectionsForPC(pc, sects); 2547 have_sects = true; 2548 } 2549 if (have_sects) { 2550 #if defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND) 2551 // If there is a compact unwind encoding table, look there first. 2552 if (sects.compact_unwind_section != 0) { 2553 if (this->getInfoFromCompactEncodingSection(pc, sects)) { 2554 #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 2555 // Found info in table, done unless encoding says to use dwarf. 2556 uint32_t dwarfOffset; 2557 if ((sects.dwarf_section != 0) && compactSaysUseDwarf(&dwarfOffset)) { 2558 if (this->getInfoFromDwarfSection(pc, sects, dwarfOffset)) { 2559 // found info in dwarf, done 2560 return; 2561 } 2562 } 2563 #endif 2564 // If unwind table has entry, but entry says there is no unwind info, 2565 // record that we have no unwind info. 2566 if (_info.format == 0) 2567 _unwindInfoMissing = true; 2568 return; 2569 } 2570 } 2571 #endif // defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND) 2572 2573 #if defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) 2574 // If there is SEH unwind info, look there next. 2575 if (this->getInfoFromSEH(pc)) 2576 return; 2577 #endif 2578 2579 #if defined(_LIBUNWIND_SUPPORT_TBTAB_UNWIND) 2580 // If there is unwind info in the traceback table, look there next. 2581 if (this->getInfoFromTBTable(pc, _registers)) 2582 return; 2583 #endif 2584 2585 #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 2586 // If there is dwarf unwind info, look there next. 2587 if (sects.dwarf_section != 0) { 2588 if (this->getInfoFromDwarfSection(pc, sects)) { 2589 // found info in dwarf, done 2590 return; 2591 } 2592 } 2593 #endif 2594 2595 #if defined(_LIBUNWIND_ARM_EHABI) 2596 // If there is ARM EHABI unwind info, look there next. 2597 if (sects.arm_section != 0 && this->getInfoFromEHABISection(pc, sects)) 2598 return; 2599 #endif 2600 } 2601 2602 #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 2603 // There is no static unwind info for this pc. Look to see if an FDE was 2604 // dynamically registered for it. 2605 pint_t cachedFDE = DwarfFDECache<A>::findFDE(DwarfFDECache<A>::kSearchAll, 2606 pc); 2607 if (cachedFDE != 0) { 2608 typename CFI_Parser<A>::FDE_Info fdeInfo; 2609 typename CFI_Parser<A>::CIE_Info cieInfo; 2610 if (!CFI_Parser<A>::decodeFDE(_addressSpace, cachedFDE, &fdeInfo, &cieInfo)) 2611 if (getInfoFromFdeCie(fdeInfo, cieInfo, pc, 0)) 2612 return; 2613 } 2614 2615 // Lastly, ask AddressSpace object about platform specific ways to locate 2616 // other FDEs. 2617 pint_t fde; 2618 if (_addressSpace.findOtherFDE(pc, fde)) { 2619 typename CFI_Parser<A>::FDE_Info fdeInfo; 2620 typename CFI_Parser<A>::CIE_Info cieInfo; 2621 if (!CFI_Parser<A>::decodeFDE(_addressSpace, fde, &fdeInfo, &cieInfo)) { 2622 // Double check this FDE is for a function that includes the pc. 2623 if ((fdeInfo.pcStart <= pc) && (pc < fdeInfo.pcEnd)) 2624 if (getInfoFromFdeCie(fdeInfo, cieInfo, pc, 0)) 2625 return; 2626 } 2627 } 2628 #endif // #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 2629 2630 #if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) 2631 if (setInfoForSigReturn()) 2632 return; 2633 #endif 2634 2635 // no unwind info, flag that we can't reliably unwind 2636 _unwindInfoMissing = true; 2637 } 2638 2639 #if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) && \ 2640 defined(_LIBUNWIND_TARGET_AARCH64) 2641 template <typename A, typename R> 2642 bool UnwindCursor<A, R>::setInfoForSigReturn(Registers_arm64 &) { 2643 // Look for the sigreturn trampoline. The trampoline's body is two 2644 // specific instructions (see below). Typically the trampoline comes from the 2645 // vDSO[1] (i.e. the __kernel_rt_sigreturn function). A libc might provide its 2646 // own restorer function, though, or user-mode QEMU might write a trampoline 2647 // onto the stack. 2648 // 2649 // This special code path is a fallback that is only used if the trampoline 2650 // lacks proper (e.g. DWARF) unwind info. On AArch64, a new DWARF register 2651 // constant for the PC needs to be defined before DWARF can handle a signal 2652 // trampoline. This code may segfault if the target PC is unreadable, e.g.: 2653 // - The PC points at a function compiled without unwind info, and which is 2654 // part of an execute-only mapping (e.g. using -Wl,--execute-only). 2655 // - The PC is invalid and happens to point to unreadable or unmapped memory. 2656 // 2657 // [1] https://github.com/torvalds/linux/blob/master/arch/arm64/kernel/vdso/sigreturn.S 2658 const pint_t pc = static_cast<pint_t>(this->getReg(UNW_REG_IP)); 2659 // The PC might contain an invalid address if the unwind info is bad, so 2660 // directly accessing it could cause a segfault. Use process_vm_readv to read 2661 // the memory safely instead. process_vm_readv was added in Linux 3.2, and 2662 // AArch64 supported was added in Linux 3.7, so the syscall is guaranteed to 2663 // be present. Unfortunately, there are Linux AArch64 environments where the 2664 // libc wrapper for the syscall might not be present (e.g. Android 5), so call 2665 // the syscall directly instead. 2666 uint32_t instructions[2]; 2667 struct iovec local_iov = {&instructions, sizeof instructions}; 2668 struct iovec remote_iov = {reinterpret_cast<void *>(pc), sizeof instructions}; 2669 long bytesRead = 2670 syscall(SYS_process_vm_readv, getpid(), &local_iov, 1, &remote_iov, 1, 0); 2671 // Look for instructions: mov x8, #0x8b; svc #0x0 2672 if (bytesRead != sizeof instructions || instructions[0] != 0xd2801168 || 2673 instructions[1] != 0xd4000001) 2674 return false; 2675 2676 _info = {}; 2677 _info.start_ip = pc; 2678 _info.end_ip = pc + 4; 2679 _isSigReturn = true; 2680 return true; 2681 } 2682 2683 template <typename A, typename R> 2684 int UnwindCursor<A, R>::stepThroughSigReturn(Registers_arm64 &) { 2685 // In the signal trampoline frame, sp points to an rt_sigframe[1], which is: 2686 // - 128-byte siginfo struct 2687 // - ucontext struct: 2688 // - 8-byte long (uc_flags) 2689 // - 8-byte pointer (uc_link) 2690 // - 24-byte stack_t 2691 // - 128-byte signal set 2692 // - 8 bytes of padding because sigcontext has 16-byte alignment 2693 // - sigcontext/mcontext_t 2694 // [1] https://github.com/torvalds/linux/blob/master/arch/arm64/kernel/signal.c 2695 const pint_t kOffsetSpToSigcontext = (128 + 8 + 8 + 24 + 128 + 8); // 304 2696 2697 // Offsets from sigcontext to each register. 2698 const pint_t kOffsetGprs = 8; // offset to "__u64 regs[31]" field 2699 const pint_t kOffsetSp = 256; // offset to "__u64 sp" field 2700 const pint_t kOffsetPc = 264; // offset to "__u64 pc" field 2701 2702 pint_t sigctx = _registers.getSP() + kOffsetSpToSigcontext; 2703 2704 for (int i = 0; i <= 30; ++i) { 2705 uint64_t value = _addressSpace.get64(sigctx + kOffsetGprs + 2706 static_cast<pint_t>(i * 8)); 2707 _registers.setRegister(UNW_AARCH64_X0 + i, value); 2708 } 2709 _registers.setSP(_addressSpace.get64(sigctx + kOffsetSp)); 2710 _registers.setIP(_addressSpace.get64(sigctx + kOffsetPc)); 2711 _isSignalFrame = true; 2712 return UNW_STEP_SUCCESS; 2713 } 2714 #endif // defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) && 2715 // defined(_LIBUNWIND_TARGET_AARCH64) 2716 2717 #if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) && \ 2718 defined(_LIBUNWIND_TARGET_S390X) 2719 template <typename A, typename R> 2720 bool UnwindCursor<A, R>::setInfoForSigReturn(Registers_s390x &) { 2721 // Look for the sigreturn trampoline. The trampoline's body is a 2722 // specific instruction (see below). Typically the trampoline comes from the 2723 // vDSO (i.e. the __kernel_[rt_]sigreturn function). A libc might provide its 2724 // own restorer function, though, or user-mode QEMU might write a trampoline 2725 // onto the stack. 2726 const pint_t pc = static_cast<pint_t>(this->getReg(UNW_REG_IP)); 2727 // The PC might contain an invalid address if the unwind info is bad, so 2728 // directly accessing it could cause a segfault. Use process_vm_readv to 2729 // read the memory safely instead. 2730 uint16_t inst; 2731 struct iovec local_iov = {&inst, sizeof inst}; 2732 struct iovec remote_iov = {reinterpret_cast<void *>(pc), sizeof inst}; 2733 long bytesRead = process_vm_readv(getpid(), &local_iov, 1, &remote_iov, 1, 0); 2734 if (bytesRead == sizeof inst && (inst == 0x0a77 || inst == 0x0aad)) { 2735 _info = {}; 2736 _info.start_ip = pc; 2737 _info.end_ip = pc + 2; 2738 _isSigReturn = true; 2739 return true; 2740 } 2741 return false; 2742 } 2743 2744 template <typename A, typename R> 2745 int UnwindCursor<A, R>::stepThroughSigReturn(Registers_s390x &) { 2746 // Determine current SP. 2747 const pint_t sp = static_cast<pint_t>(this->getReg(UNW_REG_SP)); 2748 // According to the s390x ABI, the CFA is at (incoming) SP + 160. 2749 const pint_t cfa = sp + 160; 2750 2751 // Determine current PC and instruction there (this must be either 2752 // a "svc __NR_sigreturn" or "svc __NR_rt_sigreturn"). 2753 const pint_t pc = static_cast<pint_t>(this->getReg(UNW_REG_IP)); 2754 const uint16_t inst = _addressSpace.get16(pc); 2755 2756 // Find the addresses of the signo and sigcontext in the frame. 2757 pint_t pSigctx = 0; 2758 pint_t pSigno = 0; 2759 2760 // "svc __NR_sigreturn" uses a non-RT signal trampoline frame. 2761 if (inst == 0x0a77) { 2762 // Layout of a non-RT signal trampoline frame, starting at the CFA: 2763 // - 8-byte signal mask 2764 // - 8-byte pointer to sigcontext, followed by signo 2765 // - 4-byte signo 2766 pSigctx = _addressSpace.get64(cfa + 8); 2767 pSigno = pSigctx + 344; 2768 } 2769 2770 // "svc __NR_rt_sigreturn" uses a RT signal trampoline frame. 2771 if (inst == 0x0aad) { 2772 // Layout of a RT signal trampoline frame, starting at the CFA: 2773 // - 8-byte retcode (+ alignment) 2774 // - 128-byte siginfo struct (starts with signo) 2775 // - ucontext struct: 2776 // - 8-byte long (uc_flags) 2777 // - 8-byte pointer (uc_link) 2778 // - 24-byte stack_t 2779 // - 8 bytes of padding because sigcontext has 16-byte alignment 2780 // - sigcontext/mcontext_t 2781 pSigctx = cfa + 8 + 128 + 8 + 8 + 24 + 8; 2782 pSigno = cfa + 8; 2783 } 2784 2785 assert(pSigctx != 0); 2786 assert(pSigno != 0); 2787 2788 // Offsets from sigcontext to each register. 2789 const pint_t kOffsetPc = 8; 2790 const pint_t kOffsetGprs = 16; 2791 const pint_t kOffsetFprs = 216; 2792 2793 // Restore all registers. 2794 for (int i = 0; i < 16; ++i) { 2795 uint64_t value = _addressSpace.get64(pSigctx + kOffsetGprs + 2796 static_cast<pint_t>(i * 8)); 2797 _registers.setRegister(UNW_S390X_R0 + i, value); 2798 } 2799 for (int i = 0; i < 16; ++i) { 2800 static const int fpr[16] = { 2801 UNW_S390X_F0, UNW_S390X_F1, UNW_S390X_F2, UNW_S390X_F3, 2802 UNW_S390X_F4, UNW_S390X_F5, UNW_S390X_F6, UNW_S390X_F7, 2803 UNW_S390X_F8, UNW_S390X_F9, UNW_S390X_F10, UNW_S390X_F11, 2804 UNW_S390X_F12, UNW_S390X_F13, UNW_S390X_F14, UNW_S390X_F15 2805 }; 2806 double value = _addressSpace.getDouble(pSigctx + kOffsetFprs + 2807 static_cast<pint_t>(i * 8)); 2808 _registers.setFloatRegister(fpr[i], value); 2809 } 2810 _registers.setIP(_addressSpace.get64(pSigctx + kOffsetPc)); 2811 2812 // SIGILL, SIGFPE and SIGTRAP are delivered with psw_addr 2813 // after the faulting instruction rather than before it. 2814 // Do not set _isSignalFrame in that case. 2815 uint32_t signo = _addressSpace.get32(pSigno); 2816 _isSignalFrame = (signo != 4 && signo != 5 && signo != 8); 2817 2818 return UNW_STEP_SUCCESS; 2819 } 2820 #endif // defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) && 2821 // defined(_LIBUNWIND_TARGET_S390X) 2822 2823 template <typename A, typename R> int UnwindCursor<A, R>::step(bool stage2) { 2824 (void)stage2; 2825 // Bottom of stack is defined is when unwind info cannot be found. 2826 if (_unwindInfoMissing) 2827 return UNW_STEP_END; 2828 2829 // Use unwinding info to modify register set as if function returned. 2830 int result; 2831 #if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) 2832 if (_isSigReturn) { 2833 result = this->stepThroughSigReturn(); 2834 } else 2835 #endif 2836 { 2837 #if defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND) 2838 result = this->stepWithCompactEncoding(stage2); 2839 #elif defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) 2840 result = this->stepWithSEHData(); 2841 #elif defined(_LIBUNWIND_SUPPORT_TBTAB_UNWIND) 2842 result = this->stepWithTBTableData(); 2843 #elif defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) 2844 result = this->stepWithDwarfFDE(stage2); 2845 #elif defined(_LIBUNWIND_ARM_EHABI) 2846 result = this->stepWithEHABI(); 2847 #else 2848 #error Need _LIBUNWIND_SUPPORT_COMPACT_UNWIND or \ 2849 _LIBUNWIND_SUPPORT_SEH_UNWIND or \ 2850 _LIBUNWIND_SUPPORT_DWARF_UNWIND or \ 2851 _LIBUNWIND_ARM_EHABI 2852 #endif 2853 } 2854 2855 // update info based on new PC 2856 if (result == UNW_STEP_SUCCESS) { 2857 this->setInfoBasedOnIPRegister(true); 2858 if (_unwindInfoMissing) 2859 return UNW_STEP_END; 2860 } 2861 2862 return result; 2863 } 2864 2865 template <typename A, typename R> 2866 void UnwindCursor<A, R>::getInfo(unw_proc_info_t *info) { 2867 if (_unwindInfoMissing) 2868 memset(info, 0, sizeof(*info)); 2869 else 2870 *info = _info; 2871 } 2872 2873 template <typename A, typename R> 2874 bool UnwindCursor<A, R>::getFunctionName(char *buf, size_t bufLen, 2875 unw_word_t *offset) { 2876 return _addressSpace.findFunctionName((pint_t)this->getReg(UNW_REG_IP), 2877 buf, bufLen, offset); 2878 } 2879 2880 #if defined(_LIBUNWIND_USE_CET) 2881 extern "C" void *__libunwind_cet_get_registers(unw_cursor_t *cursor) { 2882 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor; 2883 return co->get_registers(); 2884 } 2885 #endif 2886 } // namespace libunwind 2887 2888 #endif // __UNWINDCURSOR_HPP__ 2889