| //===--------------------------- DwarfParser.hpp --------------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is dual licensed under the MIT and the University of Illinois Open |
| // Source Licenses. See LICENSE.TXT for details. |
| // |
| // |
| // Parses DWARF CFIs (FDEs and CIEs). |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef __DWARF_PARSER_HPP__ |
| #define __DWARF_PARSER_HPP__ |
| |
| #include <inttypes.h> |
| #include <stdint.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| |
| #include "libunwind.h" |
| #include "dwarf2.h" |
| |
| #include "config.h" |
| |
| namespace libunwind { |
| |
| /// CFI_Parser does basic parsing of a CFI (Call Frame Information) records. |
| /// See DWARF Spec for details: |
| /// http://refspecs.linuxbase.org/LSB_3.1.0/LSB-Core-generic/LSB-Core-generic/ehframechpt.html |
| /// |
| template <typename A> |
| class CFI_Parser { |
| public: |
| typedef typename A::pint_t pint_t; |
| |
| /// Information encoded in a CIE (Common Information Entry) |
| struct CIE_Info { |
| pint_t cieStart; |
| pint_t cieLength; |
| pint_t cieInstructions; |
| uint8_t pointerEncoding; |
| uint8_t lsdaEncoding; |
| uint8_t personalityEncoding; |
| uint8_t personalityOffsetInCIE; |
| pint_t personality; |
| uint32_t codeAlignFactor; |
| int dataAlignFactor; |
| bool isSignalFrame; |
| bool fdesHaveAugmentationData; |
| uint8_t returnAddressRegister; |
| }; |
| |
| /// Information about an FDE (Frame Description Entry) |
| struct FDE_Info { |
| pint_t fdeStart; |
| pint_t fdeLength; |
| pint_t fdeInstructions; |
| pint_t pcStart; |
| pint_t pcEnd; |
| pint_t lsda; |
| }; |
| |
| enum { |
| kMaxRegisterNumber = _LIBUNWIND_HIGHEST_DWARF_REGISTER |
| }; |
| enum RegisterSavedWhere { |
| kRegisterUnused, |
| kRegisterInCFA, |
| kRegisterOffsetFromCFA, |
| kRegisterInRegister, |
| kRegisterAtExpression, |
| kRegisterIsExpression |
| }; |
| struct RegisterLocation { |
| RegisterSavedWhere location; |
| int64_t value; |
| }; |
| /// Information about a frame layout and registers saved determined |
| /// by "running" the DWARF FDE "instructions" |
| struct PrologInfo { |
| uint32_t cfaRegister; |
| int32_t cfaRegisterOffset; // CFA = (cfaRegister)+cfaRegisterOffset |
| int64_t cfaExpression; // CFA = expression |
| uint32_t spExtraArgSize; |
| uint32_t codeOffsetAtStackDecrement; |
| bool registersInOtherRegisters; |
| bool sameValueUsed; |
| RegisterLocation savedRegisters[kMaxRegisterNumber + 1]; |
| }; |
| |
| struct PrologInfoStackEntry { |
| PrologInfoStackEntry(PrologInfoStackEntry *n, const PrologInfo &i) |
| : next(n), info(i) {} |
| PrologInfoStackEntry *next; |
| PrologInfo info; |
| }; |
| |
| static bool findFDE(A &addressSpace, pint_t pc, pint_t ehSectionStart, |
| uint32_t sectionLength, pint_t fdeHint, FDE_Info *fdeInfo, |
| CIE_Info *cieInfo); |
| static const char *decodeFDE(A &addressSpace, pint_t fdeStart, |
| FDE_Info *fdeInfo, CIE_Info *cieInfo); |
| static bool parseFDEInstructions(A &addressSpace, const FDE_Info &fdeInfo, |
| const CIE_Info &cieInfo, pint_t upToPC, |
| PrologInfo *results); |
| |
| static const char *parseCIE(A &addressSpace, pint_t cie, CIE_Info *cieInfo); |
| |
| private: |
| static bool parseInstructions(A &addressSpace, pint_t instructions, |
| pint_t instructionsEnd, const CIE_Info &cieInfo, |
| pint_t pcoffset, |
| PrologInfoStackEntry *&rememberStack, |
| PrologInfo *results); |
| }; |
| |
| /// Parse a FDE into a CIE_Info and an FDE_Info |
| template <typename A> |
| const char *CFI_Parser<A>::decodeFDE(A &addressSpace, pint_t fdeStart, |
| FDE_Info *fdeInfo, CIE_Info *cieInfo) { |
| pint_t p = fdeStart; |
| pint_t cfiLength = (pint_t)addressSpace.get32(p); |
| p += 4; |
| if (cfiLength == 0xffffffff) { |
| // 0xffffffff means length is really next 8 bytes |
| cfiLength = (pint_t)addressSpace.get64(p); |
| p += 8; |
| } |
| if (cfiLength == 0) |
| return "FDE has zero length"; // end marker |
| uint32_t ciePointer = addressSpace.get32(p); |
| if (ciePointer == 0) |
| return "FDE is really a CIE"; // this is a CIE not an FDE |
| pint_t nextCFI = p + cfiLength; |
| pint_t cieStart = p - ciePointer; |
| const char *err = parseCIE(addressSpace, cieStart, cieInfo); |
| if (err != NULL) |
| return err; |
| p += 4; |
| // Parse pc begin and range. |
| pint_t pcStart = |
| addressSpace.getEncodedP(p, nextCFI, cieInfo->pointerEncoding); |
| pint_t pcRange = |
| addressSpace.getEncodedP(p, nextCFI, cieInfo->pointerEncoding & 0x0F); |
| // Parse rest of info. |
| fdeInfo->lsda = 0; |
| // Check for augmentation length. |
| if (cieInfo->fdesHaveAugmentationData) { |
| pint_t augLen = (pint_t)addressSpace.getULEB128(p, nextCFI); |
| pint_t endOfAug = p + augLen; |
| if (cieInfo->lsdaEncoding != DW_EH_PE_omit) { |
| // Peek at value (without indirection). Zero means no LSDA. |
| pint_t lsdaStart = p; |
| if (addressSpace.getEncodedP(p, nextCFI, cieInfo->lsdaEncoding & 0x0F) != |
| 0) { |
| // Reset pointer and re-parse LSDA address. |
| p = lsdaStart; |
| fdeInfo->lsda = |
| addressSpace.getEncodedP(p, nextCFI, cieInfo->lsdaEncoding); |
| } |
| } |
| p = endOfAug; |
| } |
| fdeInfo->fdeStart = fdeStart; |
| fdeInfo->fdeLength = nextCFI - fdeStart; |
| fdeInfo->fdeInstructions = p; |
| fdeInfo->pcStart = pcStart; |
| fdeInfo->pcEnd = pcStart + pcRange; |
| return NULL; // success |
| } |
| |
| /// Scan an eh_frame section to find an FDE for a pc |
| template <typename A> |
| bool CFI_Parser<A>::findFDE(A &addressSpace, pint_t pc, pint_t ehSectionStart, |
| uint32_t sectionLength, pint_t fdeHint, |
| FDE_Info *fdeInfo, CIE_Info *cieInfo) { |
| //fprintf(stderr, "findFDE(0x%llX)\n", (long long)pc); |
| pint_t p = (fdeHint != 0) ? fdeHint : ehSectionStart; |
| const pint_t ehSectionEnd = p + sectionLength; |
| while (p < ehSectionEnd) { |
| pint_t currentCFI = p; |
| //fprintf(stderr, "findFDE() CFI at 0x%llX\n", (long long)p); |
| pint_t cfiLength = addressSpace.get32(p); |
| p += 4; |
| if (cfiLength == 0xffffffff) { |
| // 0xffffffff means length is really next 8 bytes |
| cfiLength = (pint_t)addressSpace.get64(p); |
| p += 8; |
| } |
| if (cfiLength == 0) |
| return false; // end marker |
| uint32_t id = addressSpace.get32(p); |
| if (id == 0) { |
| // Skip over CIEs. |
| p += cfiLength; |
| } else { |
| // Process FDE to see if it covers pc. |
| pint_t nextCFI = p + cfiLength; |
| uint32_t ciePointer = addressSpace.get32(p); |
| pint_t cieStart = p - ciePointer; |
| // Validate pointer to CIE is within section. |
| if ((ehSectionStart <= cieStart) && (cieStart < ehSectionEnd)) { |
| if (parseCIE(addressSpace, cieStart, cieInfo) == NULL) { |
| p += 4; |
| // Parse pc begin and range. |
| pint_t pcStart = |
| addressSpace.getEncodedP(p, nextCFI, cieInfo->pointerEncoding); |
| pint_t pcRange = addressSpace.getEncodedP( |
| p, nextCFI, cieInfo->pointerEncoding & 0x0F); |
| // Test if pc is within the function this FDE covers. |
| if ((pcStart < pc) && (pc <= pcStart + pcRange)) { |
| // parse rest of info |
| fdeInfo->lsda = 0; |
| // check for augmentation length |
| if (cieInfo->fdesHaveAugmentationData) { |
| pint_t augLen = (pint_t)addressSpace.getULEB128(p, nextCFI); |
| pint_t endOfAug = p + augLen; |
| if (cieInfo->lsdaEncoding != DW_EH_PE_omit) { |
| // Peek at value (without indirection). Zero means no LSDA. |
| pint_t lsdaStart = p; |
| if (addressSpace.getEncodedP( |
| p, nextCFI, cieInfo->lsdaEncoding & 0x0F) != 0) { |
| // Reset pointer and re-parse LSDA address. |
| p = lsdaStart; |
| fdeInfo->lsda = addressSpace |
| .getEncodedP(p, nextCFI, cieInfo->lsdaEncoding); |
| } |
| } |
| p = endOfAug; |
| } |
| fdeInfo->fdeStart = currentCFI; |
| fdeInfo->fdeLength = nextCFI - currentCFI; |
| fdeInfo->fdeInstructions = p; |
| fdeInfo->pcStart = pcStart; |
| fdeInfo->pcEnd = pcStart + pcRange; |
| return true; |
| } else { |
| // pc is not in begin/range, skip this FDE |
| } |
| } else { |
| // Malformed CIE, now augmentation describing pc range encoding. |
| } |
| } else { |
| // malformed FDE. CIE is bad |
| } |
| p = nextCFI; |
| } |
| } |
| return false; |
| } |
| |
| /// Extract info from a CIE |
| template <typename A> |
| const char *CFI_Parser<A>::parseCIE(A &addressSpace, pint_t cie, |
| CIE_Info *cieInfo) { |
| cieInfo->pointerEncoding = 0; |
| cieInfo->lsdaEncoding = DW_EH_PE_omit; |
| cieInfo->personalityEncoding = 0; |
| cieInfo->personalityOffsetInCIE = 0; |
| cieInfo->personality = 0; |
| cieInfo->codeAlignFactor = 0; |
| cieInfo->dataAlignFactor = 0; |
| cieInfo->isSignalFrame = false; |
| cieInfo->fdesHaveAugmentationData = false; |
| cieInfo->cieStart = cie; |
| pint_t p = cie; |
| pint_t cieLength = (pint_t)addressSpace.get32(p); |
| p += 4; |
| pint_t cieContentEnd = p + cieLength; |
| if (cieLength == 0xffffffff) { |
| // 0xffffffff means length is really next 8 bytes |
| cieLength = (pint_t)addressSpace.get64(p); |
| p += 8; |
| cieContentEnd = p + cieLength; |
| } |
| if (cieLength == 0) |
| return NULL; |
| // CIE ID is always 0 |
| if (addressSpace.get32(p) != 0) |
| return "CIE ID is not zero"; |
| p += 4; |
| // Version is always 1 or 3 |
| uint8_t version = addressSpace.get8(p); |
| if ((version != 1) && (version != 3)) |
| return "CIE version is not 1 or 3"; |
| ++p; |
| // save start of augmentation string and find end |
| pint_t strStart = p; |
| while (addressSpace.get8(p) != 0) |
| ++p; |
| ++p; |
| // parse code aligment factor |
| cieInfo->codeAlignFactor = (uint32_t)addressSpace.getULEB128(p, cieContentEnd); |
| // parse data alignment factor |
| cieInfo->dataAlignFactor = (int)addressSpace.getSLEB128(p, cieContentEnd); |
| // parse return address register |
| uint64_t raReg = addressSpace.getULEB128(p, cieContentEnd); |
| assert(raReg < 255 && "return address register too large"); |
| cieInfo->returnAddressRegister = (uint8_t)raReg; |
| // parse augmentation data based on augmentation string |
| const char *result = NULL; |
| if (addressSpace.get8(strStart) == 'z') { |
| // parse augmentation data length |
| addressSpace.getULEB128(p, cieContentEnd); |
| for (pint_t s = strStart; addressSpace.get8(s) != '\0'; ++s) { |
| switch (addressSpace.get8(s)) { |
| case 'z': |
| cieInfo->fdesHaveAugmentationData = true; |
| break; |
| case 'P': |
| cieInfo->personalityEncoding = addressSpace.get8(p); |
| ++p; |
| cieInfo->personalityOffsetInCIE = (uint8_t)(p - cie); |
| cieInfo->personality = addressSpace |
| .getEncodedP(p, cieContentEnd, cieInfo->personalityEncoding); |
| break; |
| case 'L': |
| cieInfo->lsdaEncoding = addressSpace.get8(p); |
| ++p; |
| break; |
| case 'R': |
| cieInfo->pointerEncoding = addressSpace.get8(p); |
| ++p; |
| break; |
| case 'S': |
| cieInfo->isSignalFrame = true; |
| break; |
| default: |
| // ignore unknown letters |
| break; |
| } |
| } |
| } |
| cieInfo->cieLength = cieContentEnd - cieInfo->cieStart; |
| cieInfo->cieInstructions = p; |
| return result; |
| } |
| |
| |
| /// "run" the DWARF instructions and create the abstact PrologInfo for an FDE |
| template <typename A> |
| bool CFI_Parser<A>::parseFDEInstructions(A &addressSpace, |
| const FDE_Info &fdeInfo, |
| const CIE_Info &cieInfo, pint_t upToPC, |
| PrologInfo *results) { |
| // clear results |
| memset(results, '\0', sizeof(PrologInfo)); |
| PrologInfoStackEntry *rememberStack = NULL; |
| |
| // parse CIE then FDE instructions |
| return parseInstructions(addressSpace, cieInfo.cieInstructions, |
| cieInfo.cieStart + cieInfo.cieLength, cieInfo, |
| (pint_t)(-1), rememberStack, results) && |
| parseInstructions(addressSpace, fdeInfo.fdeInstructions, |
| fdeInfo.fdeStart + fdeInfo.fdeLength, cieInfo, |
| upToPC - fdeInfo.pcStart, rememberStack, results); |
| } |
| |
| /// "run" the DWARF instructions |
| template <typename A> |
| bool CFI_Parser<A>::parseInstructions(A &addressSpace, pint_t instructions, |
| pint_t instructionsEnd, |
| const CIE_Info &cieInfo, pint_t pcoffset, |
| PrologInfoStackEntry *&rememberStack, |
| PrologInfo *results) { |
| pint_t p = instructions; |
| pint_t codeOffset = 0; |
| PrologInfo initialState = *results; |
| |
| _LIBUNWIND_TRACE_DWARF("parseInstructions(instructions=0x%0" PRIx64 ")\n", |
| static_cast<uint64_t>(instructionsEnd)); |
| |
| // see DWARF Spec, section 6.4.2 for details on unwind opcodes |
| while ((p < instructionsEnd) && (codeOffset < pcoffset)) { |
| uint64_t reg; |
| uint64_t reg2; |
| int64_t offset; |
| uint64_t length; |
| uint8_t opcode = addressSpace.get8(p); |
| uint8_t operand; |
| #if !defined(_LIBUNWIND_NO_HEAP) |
| PrologInfoStackEntry *entry; |
| #endif |
| ++p; |
| switch (opcode) { |
| case DW_CFA_nop: |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_nop\n"); |
| break; |
| case DW_CFA_set_loc: |
| codeOffset = |
| addressSpace.getEncodedP(p, instructionsEnd, cieInfo.pointerEncoding); |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_set_loc\n"); |
| break; |
| case DW_CFA_advance_loc1: |
| codeOffset += (addressSpace.get8(p) * cieInfo.codeAlignFactor); |
| p += 1; |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_advance_loc1: new offset=%" PRIu64 "\n", |
| static_cast<uint64_t>(codeOffset)); |
| break; |
| case DW_CFA_advance_loc2: |
| codeOffset += (addressSpace.get16(p) * cieInfo.codeAlignFactor); |
| p += 2; |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_advance_loc2: new offset=%" PRIu64 "\n", |
| static_cast<uint64_t>(codeOffset)); |
| break; |
| case DW_CFA_advance_loc4: |
| codeOffset += (addressSpace.get32(p) * cieInfo.codeAlignFactor); |
| p += 4; |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_advance_loc4: new offset=%" PRIu64 "\n", |
| static_cast<uint64_t>(codeOffset)); |
| break; |
| case DW_CFA_offset_extended: |
| reg = addressSpace.getULEB128(p, instructionsEnd); |
| offset = (int64_t)addressSpace.getULEB128(p, instructionsEnd) |
| * cieInfo.dataAlignFactor; |
| if (reg > kMaxRegisterNumber) { |
| _LIBUNWIND_LOG0( |
| "malformed DW_CFA_offset_extended DWARF unwind, reg too big"); |
| return false; |
| } |
| results->savedRegisters[reg].location = kRegisterInCFA; |
| results->savedRegisters[reg].value = offset; |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_offset_extended(reg=%" PRIu64 ", " |
| "offset=%" PRId64 ")\n", |
| reg, offset); |
| break; |
| case DW_CFA_restore_extended: |
| reg = addressSpace.getULEB128(p, instructionsEnd); |
| if (reg > kMaxRegisterNumber) { |
| _LIBUNWIND_LOG0( |
| "malformed DW_CFA_restore_extended DWARF unwind, reg too big"); |
| return false; |
| } |
| results->savedRegisters[reg] = initialState.savedRegisters[reg]; |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_restore_extended(reg=%" PRIu64 ")\n", reg); |
| break; |
| case DW_CFA_undefined: |
| reg = addressSpace.getULEB128(p, instructionsEnd); |
| if (reg > kMaxRegisterNumber) { |
| _LIBUNWIND_LOG0( |
| "malformed DW_CFA_undefined DWARF unwind, reg too big"); |
| return false; |
| } |
| results->savedRegisters[reg].location = kRegisterUnused; |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_undefined(reg=%" PRIu64 ")\n", reg); |
| break; |
| case DW_CFA_same_value: |
| reg = addressSpace.getULEB128(p, instructionsEnd); |
| if (reg > kMaxRegisterNumber) { |
| _LIBUNWIND_LOG0( |
| "malformed DW_CFA_same_value DWARF unwind, reg too big"); |
| return false; |
| } |
| // <rdar://problem/8456377> DW_CFA_same_value unsupported |
| // "same value" means register was stored in frame, but its current |
| // value has not changed, so no need to restore from frame. |
| // We model this as if the register was never saved. |
| results->savedRegisters[reg].location = kRegisterUnused; |
| // set flag to disable conversion to compact unwind |
| results->sameValueUsed = true; |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_same_value(reg=%" PRIu64 ")\n", reg); |
| break; |
| case DW_CFA_register: |
| reg = addressSpace.getULEB128(p, instructionsEnd); |
| reg2 = addressSpace.getULEB128(p, instructionsEnd); |
| if (reg > kMaxRegisterNumber) { |
| _LIBUNWIND_LOG0( |
| "malformed DW_CFA_register DWARF unwind, reg too big"); |
| return false; |
| } |
| if (reg2 > kMaxRegisterNumber) { |
| _LIBUNWIND_LOG0( |
| "malformed DW_CFA_register DWARF unwind, reg2 too big"); |
| return false; |
| } |
| results->savedRegisters[reg].location = kRegisterInRegister; |
| results->savedRegisters[reg].value = (int64_t)reg2; |
| // set flag to disable conversion to compact unwind |
| results->registersInOtherRegisters = true; |
| _LIBUNWIND_TRACE_DWARF( |
| "DW_CFA_register(reg=%" PRIu64 ", reg2=%" PRIu64 ")\n", reg, reg2); |
| break; |
| #if !defined(_LIBUNWIND_NO_HEAP) |
| case DW_CFA_remember_state: |
| // avoid operator new, because that would be an upward dependency |
| entry = (PrologInfoStackEntry *)malloc(sizeof(PrologInfoStackEntry)); |
| if (entry != NULL) { |
| entry->next = rememberStack; |
| entry->info = *results; |
| rememberStack = entry; |
| } else { |
| return false; |
| } |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_remember_state\n"); |
| break; |
| case DW_CFA_restore_state: |
| if (rememberStack != NULL) { |
| PrologInfoStackEntry *top = rememberStack; |
| *results = top->info; |
| rememberStack = top->next; |
| free((char *)top); |
| } else { |
| return false; |
| } |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_restore_state\n"); |
| break; |
| #endif |
| case DW_CFA_def_cfa: |
| reg = addressSpace.getULEB128(p, instructionsEnd); |
| offset = (int64_t)addressSpace.getULEB128(p, instructionsEnd); |
| if (reg > kMaxRegisterNumber) { |
| _LIBUNWIND_LOG0("malformed DW_CFA_def_cfa DWARF unwind, reg too big"); |
| return false; |
| } |
| results->cfaRegister = (uint32_t)reg; |
| results->cfaRegisterOffset = (int32_t)offset; |
| _LIBUNWIND_TRACE_DWARF( |
| "DW_CFA_def_cfa(reg=%" PRIu64 ", offset=%" PRIu64 ")\n", reg, offset); |
| break; |
| case DW_CFA_def_cfa_register: |
| reg = addressSpace.getULEB128(p, instructionsEnd); |
| if (reg > kMaxRegisterNumber) { |
| _LIBUNWIND_LOG0( |
| "malformed DW_CFA_def_cfa_register DWARF unwind, reg too big"); |
| return false; |
| } |
| results->cfaRegister = (uint32_t)reg; |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_def_cfa_register(%" PRIu64 ")\n", reg); |
| break; |
| case DW_CFA_def_cfa_offset: |
| results->cfaRegisterOffset = (int32_t) |
| addressSpace.getULEB128(p, instructionsEnd); |
| results->codeOffsetAtStackDecrement = (uint32_t)codeOffset; |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_def_cfa_offset(%d)\n", |
| results->cfaRegisterOffset); |
| break; |
| case DW_CFA_def_cfa_expression: |
| results->cfaRegister = 0; |
| results->cfaExpression = (int64_t)p; |
| length = addressSpace.getULEB128(p, instructionsEnd); |
| assert(length < static_cast<pint_t>(~0) && "pointer overflow"); |
| p += static_cast<pint_t>(length); |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_def_cfa_expression(expression=0x%" PRIx64 |
| ", length=%" PRIu64 ")\n", |
| results->cfaExpression, length); |
| break; |
| case DW_CFA_expression: |
| reg = addressSpace.getULEB128(p, instructionsEnd); |
| if (reg > kMaxRegisterNumber) { |
| _LIBUNWIND_LOG0( |
| "malformed DW_CFA_expression DWARF unwind, reg too big"); |
| return false; |
| } |
| results->savedRegisters[reg].location = kRegisterAtExpression; |
| results->savedRegisters[reg].value = (int64_t)p; |
| length = addressSpace.getULEB128(p, instructionsEnd); |
| assert(length < static_cast<pint_t>(~0) && "pointer overflow"); |
| p += static_cast<pint_t>(length); |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_expression(reg=%" PRIu64 ", " |
| "expression=0x%" PRIx64 ", " |
| "length=%" PRIu64 ")\n", |
| reg, results->savedRegisters[reg].value, length); |
| break; |
| case DW_CFA_offset_extended_sf: |
| reg = addressSpace.getULEB128(p, instructionsEnd); |
| if (reg > kMaxRegisterNumber) { |
| _LIBUNWIND_LOG0( |
| "malformed DW_CFA_offset_extended_sf DWARF unwind, reg too big"); |
| return false; |
| } |
| offset = |
| addressSpace.getSLEB128(p, instructionsEnd) * cieInfo.dataAlignFactor; |
| results->savedRegisters[reg].location = kRegisterInCFA; |
| results->savedRegisters[reg].value = offset; |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_offset_extended_sf(reg=%" PRIu64 ", " |
| "offset=%" PRId64 ")\n", |
| reg, offset); |
| break; |
| case DW_CFA_def_cfa_sf: |
| reg = addressSpace.getULEB128(p, instructionsEnd); |
| offset = |
| addressSpace.getSLEB128(p, instructionsEnd) * cieInfo.dataAlignFactor; |
| if (reg > kMaxRegisterNumber) { |
| _LIBUNWIND_LOG0( |
| "malformed DW_CFA_def_cfa_sf DWARF unwind, reg too big"); |
| return false; |
| } |
| results->cfaRegister = (uint32_t)reg; |
| results->cfaRegisterOffset = (int32_t)offset; |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_def_cfa_sf(reg=%" PRIu64 ", " |
| "offset=%" PRId64 ")\n", |
| reg, offset); |
| break; |
| case DW_CFA_def_cfa_offset_sf: |
| results->cfaRegisterOffset = (int32_t) |
| (addressSpace.getSLEB128(p, instructionsEnd) * cieInfo.dataAlignFactor); |
| results->codeOffsetAtStackDecrement = (uint32_t)codeOffset; |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_def_cfa_offset_sf(%d)\n", |
| results->cfaRegisterOffset); |
| break; |
| case DW_CFA_val_offset: |
| reg = addressSpace.getULEB128(p, instructionsEnd); |
| if (reg > kMaxRegisterNumber) { |
| _LIBUNWIND_LOG( |
| "malformed DW_CFA_val_offset DWARF unwind, reg (%" PRIu64 |
| ") out of range\n", |
| reg); |
| return false; |
| } |
| offset = (int64_t)addressSpace.getULEB128(p, instructionsEnd) |
| * cieInfo.dataAlignFactor; |
| results->savedRegisters[reg].location = kRegisterOffsetFromCFA; |
| results->savedRegisters[reg].value = offset; |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_val_offset(reg=%" PRIu64 ", " |
| "offset=%" PRId64 "\n", |
| reg, offset); |
| break; |
| case DW_CFA_val_offset_sf: |
| reg = addressSpace.getULEB128(p, instructionsEnd); |
| if (reg > kMaxRegisterNumber) { |
| _LIBUNWIND_LOG0( |
| "malformed DW_CFA_val_offset_sf DWARF unwind, reg too big"); |
| return false; |
| } |
| offset = |
| addressSpace.getSLEB128(p, instructionsEnd) * cieInfo.dataAlignFactor; |
| results->savedRegisters[reg].location = kRegisterOffsetFromCFA; |
| results->savedRegisters[reg].value = offset; |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_val_offset_sf(reg=%" PRIu64 ", " |
| "offset=%" PRId64 "\n", |
| reg, offset); |
| break; |
| case DW_CFA_val_expression: |
| reg = addressSpace.getULEB128(p, instructionsEnd); |
| if (reg > kMaxRegisterNumber) { |
| _LIBUNWIND_LOG0( |
| "malformed DW_CFA_val_expression DWARF unwind, reg too big"); |
| return false; |
| } |
| results->savedRegisters[reg].location = kRegisterIsExpression; |
| results->savedRegisters[reg].value = (int64_t)p; |
| length = addressSpace.getULEB128(p, instructionsEnd); |
| assert(length < static_cast<pint_t>(~0) && "pointer overflow"); |
| p += static_cast<pint_t>(length); |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_val_expression(reg=%" PRIu64 ", " |
| "expression=0x%" PRIx64 ", length=%" PRIu64 ")\n", |
| reg, results->savedRegisters[reg].value, length); |
| break; |
| case DW_CFA_GNU_args_size: |
| length = addressSpace.getULEB128(p, instructionsEnd); |
| results->spExtraArgSize = (uint32_t)length; |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_GNU_args_size(%" PRIu64 ")\n", length); |
| break; |
| case DW_CFA_GNU_negative_offset_extended: |
| reg = addressSpace.getULEB128(p, instructionsEnd); |
| if (reg > kMaxRegisterNumber) { |
| _LIBUNWIND_LOG0("malformed DW_CFA_GNU_negative_offset_extended DWARF " |
| "unwind, reg too big"); |
| return false; |
| } |
| offset = (int64_t)addressSpace.getULEB128(p, instructionsEnd) |
| * cieInfo.dataAlignFactor; |
| results->savedRegisters[reg].location = kRegisterInCFA; |
| results->savedRegisters[reg].value = -offset; |
| _LIBUNWIND_TRACE_DWARF( |
| "DW_CFA_GNU_negative_offset_extended(%" PRId64 ")\n", offset); |
| break; |
| default: |
| operand = opcode & 0x3F; |
| switch (opcode & 0xC0) { |
| case DW_CFA_offset: |
| reg = operand; |
| if (reg > kMaxRegisterNumber) { |
| _LIBUNWIND_LOG("malformed DW_CFA_offset DWARF unwind, reg (%" PRIu64 |
| ") out of range", |
| reg); |
| return false; |
| } |
| offset = (int64_t)addressSpace.getULEB128(p, instructionsEnd) |
| * cieInfo.dataAlignFactor; |
| results->savedRegisters[reg].location = kRegisterInCFA; |
| results->savedRegisters[reg].value = offset; |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_offset(reg=%d, offset=%" PRId64 ")\n", |
| operand, offset); |
| break; |
| case DW_CFA_advance_loc: |
| codeOffset += operand * cieInfo.codeAlignFactor; |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_advance_loc: new offset=%" PRIu64 "\n", |
| static_cast<uint64_t>(codeOffset)); |
| break; |
| case DW_CFA_restore: |
| reg = operand; |
| if (reg > kMaxRegisterNumber) { |
| _LIBUNWIND_LOG("malformed DW_CFA_restore DWARF unwind, reg (%" PRIu64 |
| ") out of range", |
| reg); |
| return false; |
| } |
| results->savedRegisters[reg] = initialState.savedRegisters[reg]; |
| _LIBUNWIND_TRACE_DWARF("DW_CFA_restore(reg=%" PRIu64 ")\n", |
| static_cast<uint64_t>(operand)); |
| break; |
| default: |
| _LIBUNWIND_TRACE_DWARF("unknown CFA opcode 0x%02X\n", opcode); |
| return false; |
| } |
| } |
| } |
| |
| return true; |
| } |
| |
| } // namespace libunwind |
| |
| #endif // __DWARF_PARSER_HPP__ |
