/* * Copyright (C) 2016 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #ifndef _LIBUNWINDSTACK_DWARF_CFA_H #define _LIBUNWINDSTACK_DWARF_CFA_H #include #include #include #include #include #include #include #include #include namespace unwindstack { // DWARF Standard home: http://dwarfstd.org/ // This code is based on DWARF 4: http://http://dwarfstd.org/doc/DWARF4.pdf // See section 6.4.2.1 for a description of the DW_CFA_xxx values. class DwarfCfaInfo { public: enum DisplayType : uint8_t { DWARF_DISPLAY_NONE = 0, DWARF_DISPLAY_REGISTER, DWARF_DISPLAY_NUMBER, DWARF_DISPLAY_SIGNED_NUMBER, DWARF_DISPLAY_EVAL_BLOCK, DWARF_DISPLAY_ADDRESS, DWARF_DISPLAY_SET_LOC, DWARF_DISPLAY_ADVANCE_LOC, }; struct Info { // It may seem cleaner to just change the type of 'name' to 'const char *'. // However, having a pointer here would require relocation at runtime, // causing 'kTable' to be placed in data.rel.ro section instead of rodata // section, adding memory pressure to the system. Note that this is only // safe because this is only used in C++ code. C++ standard, unlike C // standard, mandates the array size to be large enough to hold the NULL // terminator when initialized with a string literal. const char name[36]; uint8_t supported_version; uint8_t num_operands; uint8_t operands[2]; uint8_t display_operands[2]; }; const static Info kTable[64]; }; template class DwarfCfa { // Signed version of AddressType typedef typename std::make_signed::type SignedType; public: DwarfCfa(DwarfMemory* memory, const DwarfFde* fde) : memory_(memory), fde_(fde) {} virtual ~DwarfCfa() = default; bool GetLocationInfo(uint64_t pc, uint64_t start_offset, uint64_t end_offset, dwarf_loc_regs_t* loc_regs); bool Log(uint32_t indent, uint64_t pc, uint64_t start_offset, uint64_t end_offset); const DwarfErrorData& last_error() { return last_error_; } DwarfErrorCode LastErrorCode() { return last_error_.code; } uint64_t LastErrorAddress() { return last_error_.address; } AddressType cur_pc() { return cur_pc_; } void set_cie_loc_regs(const dwarf_loc_regs_t* cie_loc_regs) { cie_loc_regs_ = cie_loc_regs; } protected: std::string GetOperandString(uint8_t operand, uint64_t value, uint64_t* cur_pc); bool LogOffsetRegisterString(uint32_t indent, uint64_t cfa_offset, uint8_t reg); bool LogInstruction(uint32_t indent, uint64_t cfa_offset, uint8_t op, uint64_t* cur_pc); private: DwarfErrorData last_error_; DwarfMemory* memory_; const DwarfFde* fde_; AddressType cur_pc_; const dwarf_loc_regs_t* cie_loc_regs_ = nullptr; std::vector operands_; std::stack loc_reg_state_; // CFA processing functions. bool cfa_nop(dwarf_loc_regs_t*); bool cfa_set_loc(dwarf_loc_regs_t*); bool cfa_advance_loc(dwarf_loc_regs_t*); bool cfa_offset(dwarf_loc_regs_t*); bool cfa_restore(dwarf_loc_regs_t*); bool cfa_undefined(dwarf_loc_regs_t*); bool cfa_same_value(dwarf_loc_regs_t*); bool cfa_register(dwarf_loc_regs_t*); bool cfa_remember_state(dwarf_loc_regs_t*); bool cfa_restore_state(dwarf_loc_regs_t*); bool cfa_def_cfa(dwarf_loc_regs_t*); bool cfa_def_cfa_register(dwarf_loc_regs_t*); bool cfa_def_cfa_offset(dwarf_loc_regs_t*); bool cfa_def_cfa_expression(dwarf_loc_regs_t*); bool cfa_expression(dwarf_loc_regs_t*); bool cfa_offset_extended_sf(dwarf_loc_regs_t*); bool cfa_def_cfa_sf(dwarf_loc_regs_t*); bool cfa_def_cfa_offset_sf(dwarf_loc_regs_t*); bool cfa_val_offset(dwarf_loc_regs_t*); bool cfa_val_offset_sf(dwarf_loc_regs_t*); bool cfa_val_expression(dwarf_loc_regs_t*); bool cfa_gnu_negative_offset_extended(dwarf_loc_regs_t*); using process_func = bool (DwarfCfa::*)(dwarf_loc_regs_t*); constexpr static process_func kCallbackTable[64] = { // 0x00 DW_CFA_nop &DwarfCfa::cfa_nop, // 0x01 DW_CFA_set_loc &DwarfCfa::cfa_set_loc, // 0x02 DW_CFA_advance_loc1 &DwarfCfa::cfa_advance_loc, // 0x03 DW_CFA_advance_loc2 &DwarfCfa::cfa_advance_loc, // 0x04 DW_CFA_advance_loc4 &DwarfCfa::cfa_advance_loc, // 0x05 DW_CFA_offset_extended &DwarfCfa::cfa_offset, // 0x06 DW_CFA_restore_extended &DwarfCfa::cfa_restore, // 0x07 DW_CFA_undefined &DwarfCfa::cfa_undefined, // 0x08 DW_CFA_same_value &DwarfCfa::cfa_same_value, // 0x09 DW_CFA_register &DwarfCfa::cfa_register, // 0x0a DW_CFA_remember_state &DwarfCfa::cfa_remember_state, // 0x0b DW_CFA_restore_state &DwarfCfa::cfa_restore_state, // 0x0c DW_CFA_def_cfa &DwarfCfa::cfa_def_cfa, // 0x0d DW_CFA_def_cfa_register &DwarfCfa::cfa_def_cfa_register, // 0x0e DW_CFA_def_cfa_offset &DwarfCfa::cfa_def_cfa_offset, // 0x0f DW_CFA_def_cfa_expression &DwarfCfa::cfa_def_cfa_expression, // 0x10 DW_CFA_expression &DwarfCfa::cfa_expression, // 0x11 DW_CFA_offset_extended_sf &DwarfCfa::cfa_offset_extended_sf, // 0x12 DW_CFA_def_cfa_sf &DwarfCfa::cfa_def_cfa_sf, // 0x13 DW_CFA_def_cfa_offset_sf &DwarfCfa::cfa_def_cfa_offset_sf, // 0x14 DW_CFA_val_offset &DwarfCfa::cfa_val_offset, // 0x15 DW_CFA_val_offset_sf &DwarfCfa::cfa_val_offset_sf, // 0x16 DW_CFA_val_expression &DwarfCfa::cfa_val_expression, // 0x17 illegal cfa nullptr, // 0x18 illegal cfa nullptr, // 0x19 illegal cfa nullptr, // 0x1a illegal cfa nullptr, // 0x1b illegal cfa nullptr, // 0x1c DW_CFA_lo_user (Treat this as illegal) nullptr, // 0x1d illegal cfa nullptr, // 0x1e illegal cfa nullptr, // 0x1f illegal cfa nullptr, // 0x20 illegal cfa nullptr, // 0x21 illegal cfa nullptr, // 0x22 illegal cfa nullptr, // 0x23 illegal cfa nullptr, // 0x24 illegal cfa nullptr, // 0x25 illegal cfa nullptr, // 0x26 illegal cfa nullptr, // 0x27 illegal cfa nullptr, // 0x28 illegal cfa nullptr, // 0x29 illegal cfa nullptr, // 0x2a illegal cfa nullptr, // 0x2b illegal cfa nullptr, // 0x2c illegal cfa nullptr, // 0x2d DW_CFA_GNU_window_save (Treat this as illegal) nullptr, // 0x2e DW_CFA_GNU_args_size &DwarfCfa::cfa_nop, // 0x2f DW_CFA_GNU_negative_offset_extended &DwarfCfa::cfa_gnu_negative_offset_extended, // 0x30 illegal cfa nullptr, // 0x31 illegal cfa nullptr, // 0x32 illegal cfa nullptr, // 0x33 illegal cfa nullptr, // 0x34 illegal cfa nullptr, // 0x35 illegal cfa nullptr, // 0x36 illegal cfa nullptr, // 0x37 illegal cfa nullptr, // 0x38 illegal cfa nullptr, // 0x39 illegal cfa nullptr, // 0x3a illegal cfa nullptr, // 0x3b illegal cfa nullptr, // 0x3c illegal cfa nullptr, // 0x3d illegal cfa nullptr, // 0x3e illegal cfa nullptr, // 0x3f DW_CFA_hi_user (Treat this as illegal) nullptr, }; }; } // namespace unwindstack #endif // _LIBUNWINDSTACK_DWARF_CFA_H