UnwindCursor.hpp revision 1.3.8.2
1 1.3.8.2 tls //===------------------------- UnwindCursor.hpp ---------------------------===// 2 1.3.8.2 tls // 3 1.3.8.2 tls // The LLVM Compiler Infrastructure 4 1.3.8.2 tls // 5 1.3.8.2 tls // This file is dual licensed under the MIT and the University of Illinois Open 6 1.3.8.2 tls // Source Licenses. See LICENSE.TXT for details. 7 1.3.8.2 tls // 8 1.3.8.2 tls // 9 1.3.8.2 tls // C++ interface to lower levels of libuwind 10 1.3.8.2 tls //===----------------------------------------------------------------------===// 11 1.3.8.2 tls 12 1.3.8.2 tls #ifndef __UNWINDCURSOR_HPP__ 13 1.3.8.2 tls #define __UNWINDCURSOR_HPP__ 14 1.3.8.2 tls 15 1.3.8.2 tls #include <stdint.h> 16 1.3.8.2 tls #include <stdlib.h> 17 1.3.8.2 tls #include <pthread.h> 18 1.3.8.2 tls 19 1.3.8.2 tls #include "AddressSpace.hpp" 20 1.3.8.2 tls #include "DwarfInstructions.hpp" 21 1.3.8.2 tls #include "Registers.hpp" 22 1.3.8.2 tls 23 1.3.8.2 tls namespace _Unwind { 24 1.3.8.2 tls 25 1.3.8.2 tls template <typename A, typename R> class UnwindCursor { 26 1.3.8.2 tls public: 27 1.3.8.2 tls UnwindCursor(R ®s, A &as) 28 1.3.8.2 tls : fRegisters(regs), fAddressSpace(as), fUnwindInfoMissing(false), 29 1.3.8.2 tls fIsSignalFrame(false) { 30 1.3.8.2 tls memset(&fInfo, 0, sizeof(fInfo)); 31 1.3.8.2 tls } 32 1.3.8.2 tls 33 1.3.8.2 tls uint64_t getIP() const { return fRegisters.getIP(); } 34 1.3.8.2 tls 35 1.3.8.2 tls void setIP(uint64_t value) { return fRegisters.setIP(value); } 36 1.3.8.2 tls 37 1.3.8.2 tls uint64_t getSP() const { return fRegisters.getSP(); } 38 1.3.8.2 tls 39 1.3.8.2 tls void setSP(uint64_t value) { return fRegisters.setSP(value); } 40 1.3.8.2 tls 41 1.3.8.2 tls bool validReg(int regNum) { return fRegisters.validRegister(regNum); } 42 1.3.8.2 tls 43 1.3.8.2 tls uint64_t getReg(int regNum) { return fRegisters.getRegister(regNum); } 44 1.3.8.2 tls 45 1.3.8.2 tls void setReg(int regNum, uint64_t value) { 46 1.3.8.2 tls fRegisters.setRegister(regNum, value); 47 1.3.8.2 tls } 48 1.3.8.2 tls 49 1.3.8.2 tls step_result step() { 50 1.3.8.2 tls // Bottom of stack is defined as having no more unwind info. 51 1.3.8.2 tls if (fUnwindInfoMissing) 52 1.3.8.2 tls return UNW_STEP_END; 53 1.3.8.2 tls 54 1.3.8.2 tls // Apply unwinding to register set. 55 1.3.8.2 tls switch (this->stepWithDwarfFDE()) { 56 1.3.8.2 tls case UNW_STEP_FAILED: 57 1.3.8.2 tls return UNW_STEP_FAILED; 58 1.3.8.2 tls case UNW_STEP_END: 59 1.3.8.2 tls return UNW_STEP_END; 60 1.3.8.2 tls case UNW_STEP_SUCCESS: 61 1.3.8.2 tls this->setInfoBasedOnIPRegister(true); 62 1.3.8.2 tls if (fUnwindInfoMissing) 63 1.3.8.2 tls return UNW_STEP_END; 64 1.3.8.2 tls 65 1.3.8.2 tls if (fInfo.extra_args) 66 1.3.8.2 tls setSP(getSP() + fInfo.extra_args); 67 1.3.8.2 tls return UNW_STEP_SUCCESS; 68 1.3.8.2 tls } 69 1.3.8.2 tls __builtin_unreachable(); 70 1.3.8.2 tls } 71 1.3.8.2 tls 72 1.3.8.2 tls void getInfo(unw_proc_info_t *info) { *info = fInfo; } 73 1.3.8.2 tls 74 1.3.8.2 tls bool isSignalFrame() { return fIsSignalFrame; } 75 1.3.8.2 tls void setInfoBasedOnIPRegister(bool isReturnAddress = false); 76 1.3.8.2 tls 77 1.3.8.2 tls void jumpto() { fRegisters.jumpto(); } 78 1.3.8.2 tls 79 1.3.8.2 tls private: 80 1.3.8.2 tls typedef typename A::pint_t pint_t; 81 1.3.8.2 tls typedef uint32_t EncodedUnwindInfo; 82 1.3.8.2 tls 83 1.3.8.2 tls bool getInfoFromDwarfSection(pint_t, pint_t, uint32_t, uint32_t); 84 1.3.8.2 tls 85 1.3.8.2 tls step_result stepWithDwarfFDE() { 86 1.3.8.2 tls return DwarfInstructions<A, R>::stepWithDwarf( 87 1.3.8.2 tls fAddressSpace, this->getIP(), fInfo.unwind_info, fRegisters, &fInfo); 88 1.3.8.2 tls } 89 1.3.8.2 tls 90 1.3.8.2 tls unw_proc_info_t fInfo; 91 1.3.8.2 tls R fRegisters; 92 1.3.8.2 tls A &fAddressSpace; 93 1.3.8.2 tls bool fUnwindInfoMissing; 94 1.3.8.2 tls bool fIsSignalFrame; 95 1.3.8.2 tls }; 96 1.3.8.2 tls 97 1.3.8.2 tls template <typename A, typename R> 98 1.3.8.2 tls void UnwindCursor<A, R>::setInfoBasedOnIPRegister(bool isReturnAddress) { 99 1.3.8.2 tls pint_t pc = this->getIP(); 100 1.3.8.2 tls 101 1.3.8.2 tls // If the last line of a function is a "throw", the compiler sometimes 102 1.3.8.2 tls // emits no instructions after the call to __cxa_throw. This means 103 1.3.8.2 tls // the return address is actually the start of the next function. 104 1.3.8.2 tls // To disambiguate this, back up the PC when we know it is a return 105 1.3.8.2 tls // address. 106 1.3.8.2 tls if (isReturnAddress) 107 1.3.8.2 tls --pc; 108 1.3.8.2 tls 109 1.3.8.2 tls pint_t fdeStart, data_base; 110 1.3.8.2 tls if (!fAddressSpace.findFDE(pc, fdeStart, data_base)) { 111 1.3.8.2 tls fUnwindInfoMissing = true; 112 1.3.8.2 tls return; 113 1.3.8.2 tls } 114 1.3.8.2 tls fInfo.data_base = data_base; 115 1.3.8.2 tls 116 1.3.8.2 tls typename CFI_Parser<A, R>::FDE_Info fdeInfo; 117 1.3.8.2 tls typename CFI_Parser<A, R>::CIE_Info cieInfo; 118 1.3.8.2 tls CFI_Parser<A, R>::decodeFDE(fAddressSpace, fdeStart, &fdeInfo, &cieInfo, 119 1.3.8.2 tls &fInfo); 120 1.3.8.2 tls if (pc < fdeInfo.pcStart || pc > fdeInfo.pcEnd) { 121 1.3.8.2 tls fUnwindInfoMissing = true; 122 1.3.8.2 tls return; 123 1.3.8.2 tls } 124 1.3.8.2 tls fInfo.start_ip = fdeInfo.pcStart; 125 1.3.8.2 tls 126 1.3.8.2 tls typename CFI_Parser<A, R>::PrologInfo prolog; 127 1.3.8.2 tls if (!CFI_Parser<A, R>::parseFDEInstructions(fAddressSpace, fdeInfo, cieInfo, 128 1.3.8.2 tls pc, &prolog, &fInfo)) { 129 1.3.8.2 tls fUnwindInfoMissing = true; 130 1.3.8.2 tls return; 131 1.3.8.2 tls } 132 1.3.8.2 tls // Save off parsed FDE info 133 1.3.8.2 tls fInfo.end_ip = fdeInfo.pcEnd; 134 1.3.8.2 tls fInfo.lsda = fdeInfo.lsda; 135 1.3.8.2 tls fInfo.handler = cieInfo.personality; 136 1.3.8.2 tls fInfo.extra_args = prolog.spExtraArgSize; 137 1.3.8.2 tls fInfo.unwind_info = fdeInfo.fdeStart; 138 1.3.8.2 tls } 139 1.3.8.2 tls 140 1.3.8.2 tls }; // namespace _Unwind 141 1.3.8.2 tls 142 1.3.8.2 tls #endif // __UNWINDCURSOR_HPP__ 143
Indexes created Wed Sep 24 22:09:59 GMT 2025