diff options
Diffstat (limited to 'tools/profiler/lul/LulDwarf.cpp')
| -rw-r--r-- | tools/profiler/lul/LulDwarf.cpp | 2180 |
1 files changed, 0 insertions, 2180 deletions
diff --git a/tools/profiler/lul/LulDwarf.cpp b/tools/profiler/lul/LulDwarf.cpp deleted file mode 100644 index 1bdbdabb6..000000000 --- a/tools/profiler/lul/LulDwarf.cpp +++ /dev/null @@ -1,2180 +0,0 @@ -/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ -/* vim: set ts=8 sts=2 et sw=2 tw=80: */ - -// Copyright (c) 2010 Google Inc. All Rights Reserved. -// -// Redistribution and use in source and binary forms, with or without -// modification, are permitted provided that the following conditions are -// met: -// -// * Redistributions of source code must retain the above copyright -// notice, this list of conditions and the following disclaimer. -// * Redistributions in binary form must reproduce the above -// copyright notice, this list of conditions and the following disclaimer -// in the documentation and/or other materials provided with the -// distribution. -// * Neither the name of Google Inc. nor the names of its -// contributors may be used to endorse or promote products derived from -// this software without specific prior written permission. -// -// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS -// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT -// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR -// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT -// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, -// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT -// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, -// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY -// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT -// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE -// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - -// CFI reader author: Jim Blandy <jimb@mozilla.com> <jimb@red-bean.com> -// Original author: Jim Blandy <jimb@mozilla.com> <jimb@red-bean.com> - -// Implementation of dwarf2reader::LineInfo, dwarf2reader::CompilationUnit, -// and dwarf2reader::CallFrameInfo. See dwarf2reader.h for details. - -// This file is derived from the following files in -// toolkit/crashreporter/google-breakpad: -// src/common/dwarf/bytereader.cc -// src/common/dwarf/dwarf2reader.cc -// src/common/dwarf_cfi_to_module.cc - -#include <stdint.h> -#include <stdio.h> -#include <string.h> -#include <stdlib.h> - -#include <map> -#include <stack> -#include <string> - -#include "mozilla/Assertions.h" -#include "mozilla/Sprintf.h" - -#include "LulCommonExt.h" -#include "LulDwarfInt.h" - - -// Set this to 1 for verbose logging -#define DEBUG_DWARF 0 - - -namespace lul { - -using std::string; - -ByteReader::ByteReader(enum Endianness endian) - :offset_reader_(NULL), address_reader_(NULL), endian_(endian), - address_size_(0), offset_size_(0), - have_section_base_(), have_text_base_(), have_data_base_(), - have_function_base_() { } - -ByteReader::~ByteReader() { } - -void ByteReader::SetOffsetSize(uint8 size) { - offset_size_ = size; - MOZ_ASSERT(size == 4 || size == 8); - if (size == 4) { - this->offset_reader_ = &ByteReader::ReadFourBytes; - } else { - this->offset_reader_ = &ByteReader::ReadEightBytes; - } -} - -void ByteReader::SetAddressSize(uint8 size) { - address_size_ = size; - MOZ_ASSERT(size == 4 || size == 8); - if (size == 4) { - this->address_reader_ = &ByteReader::ReadFourBytes; - } else { - this->address_reader_ = &ByteReader::ReadEightBytes; - } -} - -uint64 ByteReader::ReadInitialLength(const char* start, size_t* len) { - const uint64 initial_length = ReadFourBytes(start); - start += 4; - - // In DWARF2/3, if the initial length is all 1 bits, then the offset - // size is 8 and we need to read the next 8 bytes for the real length. - if (initial_length == 0xffffffff) { - SetOffsetSize(8); - *len = 12; - return ReadOffset(start); - } else { - SetOffsetSize(4); - *len = 4; - } - return initial_length; -} - -bool ByteReader::ValidEncoding(DwarfPointerEncoding encoding) const { - if (encoding == DW_EH_PE_omit) return true; - if (encoding == DW_EH_PE_aligned) return true; - if ((encoding & 0x7) > DW_EH_PE_udata8) - return false; - if ((encoding & 0x70) > DW_EH_PE_funcrel) - return false; - return true; -} - -bool ByteReader::UsableEncoding(DwarfPointerEncoding encoding) const { - switch (encoding & 0x70) { - case DW_EH_PE_absptr: return true; - case DW_EH_PE_pcrel: return have_section_base_; - case DW_EH_PE_textrel: return have_text_base_; - case DW_EH_PE_datarel: return have_data_base_; - case DW_EH_PE_funcrel: return have_function_base_; - default: return false; - } -} - -uint64 ByteReader::ReadEncodedPointer(const char *buffer, - DwarfPointerEncoding encoding, - size_t *len) const { - // UsableEncoding doesn't approve of DW_EH_PE_omit, so we shouldn't - // see it here. - MOZ_ASSERT(encoding != DW_EH_PE_omit); - - // The Linux Standards Base 4.0 does not make this clear, but the - // GNU tools (gcc/unwind-pe.h; readelf/dwarf.c; gdb/dwarf2-frame.c) - // agree that aligned pointers are always absolute, machine-sized, - // machine-signed pointers. - if (encoding == DW_EH_PE_aligned) { - MOZ_ASSERT(have_section_base_); - - // We don't need to align BUFFER in *our* address space. Rather, we - // need to find the next position in our buffer that would be aligned - // when the .eh_frame section the buffer contains is loaded into the - // program's memory. So align assuming that buffer_base_ gets loaded at - // address section_base_, where section_base_ itself may or may not be - // aligned. - - // First, find the offset to START from the closest prior aligned - // address. - uint64 skew = section_base_ & (AddressSize() - 1); - // Now find the offset from that aligned address to buffer. - uint64 offset = skew + (buffer - buffer_base_); - // Round up to the next boundary. - uint64 aligned = (offset + AddressSize() - 1) & -AddressSize(); - // Convert back to a pointer. - const char *aligned_buffer = buffer_base_ + (aligned - skew); - // Finally, store the length and actually fetch the pointer. - *len = aligned_buffer - buffer + AddressSize(); - return ReadAddress(aligned_buffer); - } - - // Extract the value first, ignoring whether it's a pointer or an - // offset relative to some base. - uint64 offset; - switch (encoding & 0x0f) { - case DW_EH_PE_absptr: - // DW_EH_PE_absptr is weird, as it is used as a meaningful value for - // both the high and low nybble of encoding bytes. When it appears in - // the high nybble, it means that the pointer is absolute, not an - // offset from some base address. When it appears in the low nybble, - // as here, it means that the pointer is stored as a normal - // machine-sized and machine-signed address. A low nybble of - // DW_EH_PE_absptr does not imply that the pointer is absolute; it is - // correct for us to treat the value as an offset from a base address - // if the upper nybble is not DW_EH_PE_absptr. - offset = ReadAddress(buffer); - *len = AddressSize(); - break; - - case DW_EH_PE_uleb128: - offset = ReadUnsignedLEB128(buffer, len); - break; - - case DW_EH_PE_udata2: - offset = ReadTwoBytes(buffer); - *len = 2; - break; - - case DW_EH_PE_udata4: - offset = ReadFourBytes(buffer); - *len = 4; - break; - - case DW_EH_PE_udata8: - offset = ReadEightBytes(buffer); - *len = 8; - break; - - case DW_EH_PE_sleb128: - offset = ReadSignedLEB128(buffer, len); - break; - - case DW_EH_PE_sdata2: - offset = ReadTwoBytes(buffer); - // Sign-extend from 16 bits. - offset = (offset ^ 0x8000) - 0x8000; - *len = 2; - break; - - case DW_EH_PE_sdata4: - offset = ReadFourBytes(buffer); - // Sign-extend from 32 bits. - offset = (offset ^ 0x80000000ULL) - 0x80000000ULL; - *len = 4; - break; - - case DW_EH_PE_sdata8: - // No need to sign-extend; this is the full width of our type. - offset = ReadEightBytes(buffer); - *len = 8; - break; - - default: - abort(); - } - - // Find the appropriate base address. - uint64 base; - switch (encoding & 0x70) { - case DW_EH_PE_absptr: - base = 0; - break; - - case DW_EH_PE_pcrel: - MOZ_ASSERT(have_section_base_); - base = section_base_ + (buffer - buffer_base_); - break; - - case DW_EH_PE_textrel: - MOZ_ASSERT(have_text_base_); - base = text_base_; - break; - - case DW_EH_PE_datarel: - MOZ_ASSERT(have_data_base_); - base = data_base_; - break; - - case DW_EH_PE_funcrel: - MOZ_ASSERT(have_function_base_); - base = function_base_; - break; - - default: - abort(); - } - - uint64 pointer = base + offset; - - // Remove inappropriate upper bits. - if (AddressSize() == 4) - pointer = pointer & 0xffffffff; - else - MOZ_ASSERT(AddressSize() == sizeof(uint64)); - - return pointer; -} - - -// A DWARF rule for recovering the address or value of a register, or -// computing the canonical frame address. There is one subclass of this for -// each '*Rule' member function in CallFrameInfo::Handler. -// -// It's annoying that we have to handle Rules using pointers (because -// the concrete instances can have an arbitrary size). They're small, -// so it would be much nicer if we could just handle them by value -// instead of fretting about ownership and destruction. -// -// It seems like all these could simply be instances of std::tr1::bind, -// except that we need instances to be EqualityComparable, too. -// -// This could logically be nested within State, but then the qualified names -// get horrendous. -class CallFrameInfo::Rule { - public: - virtual ~Rule() { } - - // Tell HANDLER that, at ADDRESS in the program, REGISTER can be - // recovered using this rule. If REGISTER is kCFARegister, then this rule - // describes how to compute the canonical frame address. Return what the - // HANDLER member function returned. - virtual bool Handle(Handler *handler, uint64 address, int register) const = 0; - - // Equality on rules. We use these to decide which rules we need - // to report after a DW_CFA_restore_state instruction. - virtual bool operator==(const Rule &rhs) const = 0; - - bool operator!=(const Rule &rhs) const { return ! (*this == rhs); } - - // Return a pointer to a copy of this rule. - virtual Rule *Copy() const = 0; - - // If this is a base+offset rule, change its base register to REG. - // Otherwise, do nothing. (Ugly, but required for DW_CFA_def_cfa_register.) - virtual void SetBaseRegister(unsigned reg) { } - - // If this is a base+offset rule, change its offset to OFFSET. Otherwise, - // do nothing. (Ugly, but required for DW_CFA_def_cfa_offset.) - virtual void SetOffset(long long offset) { } - - // A RTTI workaround, to make it possible to implement equality - // comparisons on classes derived from this one. - enum CFIRTag { - CFIR_UNDEFINED_RULE, - CFIR_SAME_VALUE_RULE, - CFIR_OFFSET_RULE, - CFIR_VAL_OFFSET_RULE, - CFIR_REGISTER_RULE, - CFIR_EXPRESSION_RULE, - CFIR_VAL_EXPRESSION_RULE - }; - - // Produce the tag that identifies the child class of this object. - virtual CFIRTag getTag() const = 0; -}; - -// Rule: the value the register had in the caller cannot be recovered. -class CallFrameInfo::UndefinedRule: public CallFrameInfo::Rule { - public: - UndefinedRule() { } - ~UndefinedRule() { } - CFIRTag getTag() const { return CFIR_UNDEFINED_RULE; } - bool Handle(Handler *handler, uint64 address, int reg) const { - return handler->UndefinedRule(address, reg); - } - bool operator==(const Rule &rhs) const { - if (rhs.getTag() != CFIR_UNDEFINED_RULE) return false; - return true; - } - Rule *Copy() const { return new UndefinedRule(*this); } -}; - -// Rule: the register's value is the same as that it had in the caller. -class CallFrameInfo::SameValueRule: public CallFrameInfo::Rule { - public: - SameValueRule() { } - ~SameValueRule() { } - CFIRTag getTag() const { return CFIR_SAME_VALUE_RULE; } - bool Handle(Handler *handler, uint64 address, int reg) const { - return handler->SameValueRule(address, reg); - } - bool operator==(const Rule &rhs) const { - if (rhs.getTag() != CFIR_SAME_VALUE_RULE) return false; - return true; - } - Rule *Copy() const { return new SameValueRule(*this); } -}; - -// Rule: the register is saved at OFFSET from BASE_REGISTER. BASE_REGISTER -// may be CallFrameInfo::Handler::kCFARegister. -class CallFrameInfo::OffsetRule: public CallFrameInfo::Rule { - public: - OffsetRule(int base_register, long offset) - : base_register_(base_register), offset_(offset) { } - ~OffsetRule() { } - CFIRTag getTag() const { return CFIR_OFFSET_RULE; } - bool Handle(Handler *handler, uint64 address, int reg) const { - return handler->OffsetRule(address, reg, base_register_, offset_); - } - bool operator==(const Rule &rhs) const { - if (rhs.getTag() != CFIR_OFFSET_RULE) return false; - const OffsetRule *our_rhs = static_cast<const OffsetRule *>(&rhs); - return (base_register_ == our_rhs->base_register_ && - offset_ == our_rhs->offset_); - } - Rule *Copy() const { return new OffsetRule(*this); } - // We don't actually need SetBaseRegister or SetOffset here, since they - // are only ever applied to CFA rules, for DW_CFA_def_cfa_offset, and it - // doesn't make sense to use OffsetRule for computing the CFA: it - // computes the address at which a register is saved, not a value. - private: - int base_register_; - long offset_; -}; - -// Rule: the value the register had in the caller is the value of -// BASE_REGISTER plus offset. BASE_REGISTER may be -// CallFrameInfo::Handler::kCFARegister. -class CallFrameInfo::ValOffsetRule: public CallFrameInfo::Rule { - public: - ValOffsetRule(int base_register, long offset) - : base_register_(base_register), offset_(offset) { } - ~ValOffsetRule() { } - CFIRTag getTag() const { return CFIR_VAL_OFFSET_RULE; } - bool Handle(Handler *handler, uint64 address, int reg) const { - return handler->ValOffsetRule(address, reg, base_register_, offset_); - } - bool operator==(const Rule &rhs) const { - if (rhs.getTag() != CFIR_VAL_OFFSET_RULE) return false; - const ValOffsetRule *our_rhs = static_cast<const ValOffsetRule *>(&rhs); - return (base_register_ == our_rhs->base_register_ && - offset_ == our_rhs->offset_); - } - Rule *Copy() const { return new ValOffsetRule(*this); } - void SetBaseRegister(unsigned reg) { base_register_ = reg; } - void SetOffset(long long offset) { offset_ = offset; } - private: - int base_register_; - long offset_; -}; - -// Rule: the register has been saved in another register REGISTER_NUMBER_. -class CallFrameInfo::RegisterRule: public CallFrameInfo::Rule { - public: - explicit RegisterRule(int register_number) - : register_number_(register_number) { } - ~RegisterRule() { } - CFIRTag getTag() const { return CFIR_REGISTER_RULE; } - bool Handle(Handler *handler, uint64 address, int reg) const { - return handler->RegisterRule(address, reg, register_number_); - } - bool operator==(const Rule &rhs) const { - if (rhs.getTag() != CFIR_REGISTER_RULE) return false; - const RegisterRule *our_rhs = static_cast<const RegisterRule *>(&rhs); - return (register_number_ == our_rhs->register_number_); - } - Rule *Copy() const { return new RegisterRule(*this); } - private: - int register_number_; -}; - -// Rule: EXPRESSION evaluates to the address at which the register is saved. -class CallFrameInfo::ExpressionRule: public CallFrameInfo::Rule { - public: - explicit ExpressionRule(const string &expression) - : expression_(expression) { } - ~ExpressionRule() { } - CFIRTag getTag() const { return CFIR_EXPRESSION_RULE; } - bool Handle(Handler *handler, uint64 address, int reg) const { - return handler->ExpressionRule(address, reg, expression_); - } - bool operator==(const Rule &rhs) const { - if (rhs.getTag() != CFIR_EXPRESSION_RULE) return false; - const ExpressionRule *our_rhs = static_cast<const ExpressionRule *>(&rhs); - return (expression_ == our_rhs->expression_); - } - Rule *Copy() const { return new ExpressionRule(*this); } - private: - string expression_; -}; - -// Rule: EXPRESSION evaluates to the previous value of the register. -class CallFrameInfo::ValExpressionRule: public CallFrameInfo::Rule { - public: - explicit ValExpressionRule(const string &expression) - : expression_(expression) { } - ~ValExpressionRule() { } - CFIRTag getTag() const { return CFIR_VAL_EXPRESSION_RULE; } - bool Handle(Handler *handler, uint64 address, int reg) const { - return handler->ValExpressionRule(address, reg, expression_); - } - bool operator==(const Rule &rhs) const { - if (rhs.getTag() != CFIR_VAL_EXPRESSION_RULE) return false; - const ValExpressionRule *our_rhs = - static_cast<const ValExpressionRule *>(&rhs); - return (expression_ == our_rhs->expression_); - } - Rule *Copy() const { return new ValExpressionRule(*this); } - private: - string expression_; -}; - -// A map from register numbers to rules. -class CallFrameInfo::RuleMap { - public: - RuleMap() : cfa_rule_(NULL) { } - RuleMap(const RuleMap &rhs) : cfa_rule_(NULL) { *this = rhs; } - ~RuleMap() { Clear(); } - - RuleMap &operator=(const RuleMap &rhs); - - // Set the rule for computing the CFA to RULE. Take ownership of RULE. - void SetCFARule(Rule *rule) { delete cfa_rule_; cfa_rule_ = rule; } - - // Return the current CFA rule. Unlike RegisterRule, this RuleMap retains - // ownership of the rule. We use this for DW_CFA_def_cfa_offset and - // DW_CFA_def_cfa_register, and for detecting references to the CFA before - // a rule for it has been established. - Rule *CFARule() const { return cfa_rule_; } - - // Return the rule for REG, or NULL if there is none. The caller takes - // ownership of the result. - Rule *RegisterRule(int reg) const; - - // Set the rule for computing REG to RULE. Take ownership of RULE. - void SetRegisterRule(int reg, Rule *rule); - - // Make all the appropriate calls to HANDLER as if we were changing from - // this RuleMap to NEW_RULES at ADDRESS. We use this to implement - // DW_CFA_restore_state, where lots of rules can change simultaneously. - // Return true if all handlers returned true; otherwise, return false. - bool HandleTransitionTo(Handler *handler, uint64 address, - const RuleMap &new_rules) const; - - private: - // A map from register numbers to Rules. - typedef std::map<int, Rule *> RuleByNumber; - - // Remove all register rules and clear cfa_rule_. - void Clear(); - - // The rule for computing the canonical frame address. This RuleMap owns - // this rule. - Rule *cfa_rule_; - - // A map from register numbers to postfix expressions to recover - // their values. This RuleMap owns the Rules the map refers to. - RuleByNumber registers_; -}; - -CallFrameInfo::RuleMap &CallFrameInfo::RuleMap::operator=(const RuleMap &rhs) { - Clear(); - // Since each map owns the rules it refers to, assignment must copy them. - if (rhs.cfa_rule_) cfa_rule_ = rhs.cfa_rule_->Copy(); - for (RuleByNumber::const_iterator it = rhs.registers_.begin(); - it != rhs.registers_.end(); it++) - registers_[it->first] = it->second->Copy(); - return *this; -} - -CallFrameInfo::Rule *CallFrameInfo::RuleMap::RegisterRule(int reg) const { - MOZ_ASSERT(reg != Handler::kCFARegister); - RuleByNumber::const_iterator it = registers_.find(reg); - if (it != registers_.end()) - return it->second->Copy(); - else - return NULL; -} - -void CallFrameInfo::RuleMap::SetRegisterRule(int reg, Rule *rule) { - MOZ_ASSERT(reg != Handler::kCFARegister); - MOZ_ASSERT(rule); - Rule **slot = ®isters_[reg]; - delete *slot; - *slot = rule; -} - -bool CallFrameInfo::RuleMap::HandleTransitionTo( - Handler *handler, - uint64 address, - const RuleMap &new_rules) const { - // Transition from cfa_rule_ to new_rules.cfa_rule_. - if (cfa_rule_ && new_rules.cfa_rule_) { - if (*cfa_rule_ != *new_rules.cfa_rule_ && - !new_rules.cfa_rule_->Handle(handler, address, Handler::kCFARegister)) - return false; - } else if (cfa_rule_) { - // this RuleMap has a CFA rule but new_rules doesn't. - // CallFrameInfo::Handler has no way to handle this --- and shouldn't; - // it's garbage input. The instruction interpreter should have - // detected this and warned, so take no action here. - } else if (new_rules.cfa_rule_) { - // This shouldn't be possible: NEW_RULES is some prior state, and - // there's no way to remove entries. - MOZ_ASSERT(0); - } else { - // Both CFA rules are empty. No action needed. - } - - // Traverse the two maps in order by register number, and report - // whatever differences we find. - RuleByNumber::const_iterator old_it = registers_.begin(); - RuleByNumber::const_iterator new_it = new_rules.registers_.begin(); - while (old_it != registers_.end() && new_it != new_rules.registers_.end()) { - if (old_it->first < new_it->first) { - // This RuleMap has an entry for old_it->first, but NEW_RULES - // doesn't. - // - // This isn't really the right thing to do, but since CFI generally - // only mentions callee-saves registers, and GCC's convention for - // callee-saves registers is that they are unchanged, it's a good - // approximation. - if (!handler->SameValueRule(address, old_it->first)) - return false; - old_it++; - } else if (old_it->first > new_it->first) { - // NEW_RULES has entry for new_it->first, but this RuleMap - // doesn't. This shouldn't be possible: NEW_RULES is some prior - // state, and there's no way to remove entries. - MOZ_ASSERT(0); - } else { - // Both maps have an entry for this register. Report the new - // rule if it is different. - if (*old_it->second != *new_it->second && - !new_it->second->Handle(handler, address, new_it->first)) - return false; - new_it++, old_it++; - } - } - // Finish off entries from this RuleMap with no counterparts in new_rules. - while (old_it != registers_.end()) { - if (!handler->SameValueRule(address, old_it->first)) - return false; - old_it++; - } - // Since we only make transitions from a rule set to some previously - // saved rule set, and we can only add rules to the map, NEW_RULES - // must have fewer rules than *this. - MOZ_ASSERT(new_it == new_rules.registers_.end()); - - return true; -} - -// Remove all register rules and clear cfa_rule_. -void CallFrameInfo::RuleMap::Clear() { - delete cfa_rule_; - cfa_rule_ = NULL; - for (RuleByNumber::iterator it = registers_.begin(); - it != registers_.end(); it++) - delete it->second; - registers_.clear(); -} - -// The state of the call frame information interpreter as it processes -// instructions from a CIE and FDE. -class CallFrameInfo::State { - public: - // Create a call frame information interpreter state with the given - // reporter, reader, handler, and initial call frame info address. - State(ByteReader *reader, Handler *handler, Reporter *reporter, - uint64 address) - : reader_(reader), handler_(handler), reporter_(reporter), - address_(address), entry_(NULL), cursor_(NULL), - saved_rules_(NULL) { } - - ~State() { - if (saved_rules_) - delete saved_rules_; - } - - // Interpret instructions from CIE, save the resulting rule set for - // DW_CFA_restore instructions, and return true. On error, report - // the problem to reporter_ and return false. - bool InterpretCIE(const CIE &cie); - - // Interpret instructions from FDE, and return true. On error, - // report the problem to reporter_ and return false. - bool InterpretFDE(const FDE &fde); - - private: - // The operands of a CFI instruction, for ParseOperands. - struct Operands { - unsigned register_number; // A register number. - uint64 offset; // An offset or address. - long signed_offset; // A signed offset. - string expression; // A DWARF expression. - }; - - // Parse CFI instruction operands from STATE's instruction stream as - // described by FORMAT. On success, populate OPERANDS with the - // results, and return true. On failure, report the problem and - // return false. - // - // Each character of FORMAT should be one of the following: - // - // 'r' unsigned LEB128 register number (OPERANDS->register_number) - // 'o' unsigned LEB128 offset (OPERANDS->offset) - // 's' signed LEB128 offset (OPERANDS->signed_offset) - // 'a' machine-size address (OPERANDS->offset) - // (If the CIE has a 'z' augmentation string, 'a' uses the - // encoding specified by the 'R' argument.) - // '1' a one-byte offset (OPERANDS->offset) - // '2' a two-byte offset (OPERANDS->offset) - // '4' a four-byte offset (OPERANDS->offset) - // '8' an eight-byte offset (OPERANDS->offset) - // 'e' a DW_FORM_block holding a (OPERANDS->expression) - // DWARF expression - bool ParseOperands(const char *format, Operands *operands); - - // Interpret one CFI instruction from STATE's instruction stream, update - // STATE, report any rule changes to handler_, and return true. On - // failure, report the problem and return false. - bool DoInstruction(); - - // The following Do* member functions are subroutines of DoInstruction, - // factoring out the actual work of operations that have several - // different encodings. - - // Set the CFA rule to be the value of BASE_REGISTER plus OFFSET, and - // return true. On failure, report and return false. (Used for - // DW_CFA_def_cfa and DW_CFA_def_cfa_sf.) - bool DoDefCFA(unsigned base_register, long offset); - - // Change the offset of the CFA rule to OFFSET, and return true. On - // failure, report and return false. (Subroutine for - // DW_CFA_def_cfa_offset and DW_CFA_def_cfa_offset_sf.) - bool DoDefCFAOffset(long offset); - - // Specify that REG can be recovered using RULE, and return true. On - // failure, report and return false. - bool DoRule(unsigned reg, Rule *rule); - - // Specify that REG can be found at OFFSET from the CFA, and return true. - // On failure, report and return false. (Subroutine for DW_CFA_offset, - // DW_CFA_offset_extended, and DW_CFA_offset_extended_sf.) - bool DoOffset(unsigned reg, long offset); - - // Specify that the caller's value for REG is the CFA plus OFFSET, - // and return true. On failure, report and return false. (Subroutine - // for DW_CFA_val_offset and DW_CFA_val_offset_sf.) - bool DoValOffset(unsigned reg, long offset); - - // Restore REG to the rule established in the CIE, and return true. On - // failure, report and return false. (Subroutine for DW_CFA_restore and - // DW_CFA_restore_extended.) - bool DoRestore(unsigned reg); - - // Return the section offset of the instruction at cursor. For use - // in error messages. - uint64 CursorOffset() { return entry_->offset + (cursor_ - entry_->start); } - - // Report that entry_ is incomplete, and return false. For brevity. - bool ReportIncomplete() { - reporter_->Incomplete(entry_->offset, entry_->kind); - return false; - } - - // For reading multi-byte values with the appropriate endianness. - ByteReader *reader_; - - // The handler to which we should report the data we find. - Handler *handler_; - - // For reporting problems in the info we're parsing. - Reporter *reporter_; - - // The code address to which the next instruction in the stream applies. - uint64 address_; - - // The entry whose instructions we are currently processing. This is - // first a CIE, and then an FDE. - const Entry *entry_; - - // The next instruction to process. - const char *cursor_; - - // The current set of rules. - RuleMap rules_; - - // The set of rules established by the CIE, used by DW_CFA_restore - // and DW_CFA_restore_extended. We set this after interpreting the - // CIE's instructions. - RuleMap cie_rules_; - - // A stack of saved states, for DW_CFA_remember_state and - // DW_CFA_restore_state. - std::stack<RuleMap>* saved_rules_; -}; - -bool CallFrameInfo::State::InterpretCIE(const CIE &cie) { - entry_ = &cie; - cursor_ = entry_->instructions; - while (cursor_ < entry_->end) - if (!DoInstruction()) - return false; - // Note the rules established by the CIE, for use by DW_CFA_restore - // and DW_CFA_restore_extended. - cie_rules_ = rules_; - return true; -} - -bool CallFrameInfo::State::InterpretFDE(const FDE &fde) { - entry_ = &fde; - cursor_ = entry_->instructions; - while (cursor_ < entry_->end) - if (!DoInstruction()) - return false; - return true; -} - -bool CallFrameInfo::State::ParseOperands(const char *format, - Operands *operands) { - size_t len; - const char *operand; - - for (operand = format; *operand; operand++) { - size_t bytes_left = entry_->end - cursor_; - switch (*operand) { - case 'r': - operands->register_number = reader_->ReadUnsignedLEB128(cursor_, &len); - if (len > bytes_left) return ReportIncomplete(); - cursor_ += len; - break; - - case 'o': - operands->offset = reader_->ReadUnsignedLEB128(cursor_, &len); - if (len > bytes_left) return ReportIncomplete(); - cursor_ += len; - break; - - case 's': - operands->signed_offset = reader_->ReadSignedLEB128(cursor_, &len); - if (len > bytes_left) return ReportIncomplete(); - cursor_ += len; - break; - - case 'a': - operands->offset = - reader_->ReadEncodedPointer(cursor_, entry_->cie->pointer_encoding, - &len); - if (len > bytes_left) return ReportIncomplete(); - cursor_ += len; - break; - - case '1': - if (1 > bytes_left) return ReportIncomplete(); - operands->offset = static_cast<unsigned char>(*cursor_++); - break; - - case '2': - if (2 > bytes_left) return ReportIncomplete(); - operands->offset = reader_->ReadTwoBytes(cursor_); - cursor_ += 2; - break; - - case '4': - if (4 > bytes_left) return ReportIncomplete(); - operands->offset = reader_->ReadFourBytes(cursor_); - cursor_ += 4; - break; - - case '8': - if (8 > bytes_left) return ReportIncomplete(); - operands->offset = reader_->ReadEightBytes(cursor_); - cursor_ += 8; - break; - - case 'e': { - size_t expression_length = reader_->ReadUnsignedLEB128(cursor_, &len); - if (len > bytes_left || expression_length > bytes_left - len) - return ReportIncomplete(); - cursor_ += len; - operands->expression = string(cursor_, expression_length); - cursor_ += expression_length; - break; - } - - default: - MOZ_ASSERT(0); - } - } - - return true; -} - -bool CallFrameInfo::State::DoInstruction() { - CIE *cie = entry_->cie; - Operands ops; - - // Our entry's kind should have been set by now. - MOZ_ASSERT(entry_->kind != kUnknown); - - // We shouldn't have been invoked unless there were more - // instructions to parse. - MOZ_ASSERT(cursor_ < entry_->end); - - unsigned opcode = *cursor_++; - if ((opcode & 0xc0) != 0) { - switch (opcode & 0xc0) { - // Advance the address. - case DW_CFA_advance_loc: { - size_t code_offset = opcode & 0x3f; - address_ += code_offset * cie->code_alignment_factor; - break; - } - - // Find a register at an offset from the CFA. - case DW_CFA_offset: - if (!ParseOperands("o", &ops) || - !DoOffset(opcode & 0x3f, ops.offset * cie->data_alignment_factor)) - return false; - break; - - // Restore the rule established for a register by the CIE. - case DW_CFA_restore: - if (!DoRestore(opcode & 0x3f)) return false; - break; - - // The 'if' above should have excluded this possibility. - default: - MOZ_ASSERT(0); - } - - // Return here, so the big switch below won't be indented. - return true; - } - - switch (opcode) { - // Set the address. - case DW_CFA_set_loc: - if (!ParseOperands("a", &ops)) return false; - address_ = ops.offset; - break; - - // Advance the address. - case DW_CFA_advance_loc1: - if (!ParseOperands("1", &ops)) return false; - address_ += ops.offset * cie->code_alignment_factor; - break; - - // Advance the address. - case DW_CFA_advance_loc2: - if (!ParseOperands("2", &ops)) return false; - address_ += ops.offset * cie->code_alignment_factor; - break; - - // Advance the address. - case DW_CFA_advance_loc4: - if (!ParseOperands("4", &ops)) return false; - address_ += ops.offset * cie->code_alignment_factor; - break; - - // Advance the address. - case DW_CFA_MIPS_advance_loc8: - if (!ParseOperands("8", &ops)) return false; - address_ += ops.offset * cie->code_alignment_factor; - break; - - // Compute the CFA by adding an offset to a register. - case DW_CFA_def_cfa: - if (!ParseOperands("ro", &ops) || - !DoDefCFA(ops.register_number, ops.offset)) - return false; - break; - - // Compute the CFA by adding an offset to a register. - case DW_CFA_def_cfa_sf: - if (!ParseOperands("rs", &ops) || - !DoDefCFA(ops.register_number, - ops.signed_offset * cie->data_alignment_factor)) - return false; - break; - - // Change the base register used to compute the CFA. - case DW_CFA_def_cfa_register: { - Rule *cfa_rule = rules_.CFARule(); - if (!cfa_rule) { - reporter_->NoCFARule(entry_->offset, entry_->kind, CursorOffset()); - return false; - } - if (!ParseOperands("r", &ops)) return false; - cfa_rule->SetBaseRegister(ops.register_number); - if (!cfa_rule->Handle(handler_, address_, Handler::kCFARegister)) - return false; - break; - } - - // Change the offset used to compute the CFA. - case DW_CFA_def_cfa_offset: - if (!ParseOperands("o", &ops) || - !DoDefCFAOffset(ops.offset)) - return false; - break; - - // Change the offset used to compute the CFA. - case DW_CFA_def_cfa_offset_sf: - if (!ParseOperands("s", &ops) || - !DoDefCFAOffset(ops.signed_offset * cie->data_alignment_factor)) - return false; - break; - - // Specify an expression whose value is the CFA. - case DW_CFA_def_cfa_expression: { - if (!ParseOperands("e", &ops)) - return false; - Rule *rule = new ValExpressionRule(ops.expression); - rules_.SetCFARule(rule); - if (!rule->Handle(handler_, address_, Handler::kCFARegister)) - return false; - break; - } - - // The register's value cannot be recovered. - case DW_CFA_undefined: { - if (!ParseOperands("r", &ops) || - !DoRule(ops.register_number, new UndefinedRule())) - return false; - break; - } - - // The register's value is unchanged from its value in the caller. - case DW_CFA_same_value: { - if (!ParseOperands("r", &ops) || - !DoRule(ops.register_number, new SameValueRule())) - return false; - break; - } - - // Find a register at an offset from the CFA. - case DW_CFA_offset_extended: - if (!ParseOperands("ro", &ops) || - !DoOffset(ops.register_number, - ops.offset * cie->data_alignment_factor)) - return false; - break; - - // The register is saved at an offset from the CFA. - case DW_CFA_offset_extended_sf: - if (!ParseOperands("rs", &ops) || - !DoOffset(ops.register_number, - ops.signed_offset * cie->data_alignment_factor)) - return false; - break; - - // The register is saved at an offset from the CFA. - case DW_CFA_GNU_negative_offset_extended: - if (!ParseOperands("ro", &ops) || - !DoOffset(ops.register_number, - -ops.offset * cie->data_alignment_factor)) - return false; - break; - - // The register's value is the sum of the CFA plus an offset. - case DW_CFA_val_offset: - if (!ParseOperands("ro", &ops) || - !DoValOffset(ops.register_number, - ops.offset * cie->data_alignment_factor)) - return false; - break; - - // The register's value is the sum of the CFA plus an offset. - case DW_CFA_val_offset_sf: - if (!ParseOperands("rs", &ops) || - !DoValOffset(ops.register_number, - ops.signed_offset * cie->data_alignment_factor)) - return false; - break; - - // The register has been saved in another register. - case DW_CFA_register: { - if (!ParseOperands("ro", &ops) || - !DoRule(ops.register_number, new RegisterRule(ops.offset))) - return false; - break; - } - - // An expression yields the address at which the register is saved. - case DW_CFA_expression: { - if (!ParseOperands("re", &ops) || - !DoRule(ops.register_number, new ExpressionRule(ops.expression))) - return false; - break; - } - - // An expression yields the caller's value for the register. - case DW_CFA_val_expression: { - if (!ParseOperands("re", &ops) || - !DoRule(ops.register_number, new ValExpressionRule(ops.expression))) - return false; - break; - } - - // Restore the rule established for a register by the CIE. - case DW_CFA_restore_extended: - if (!ParseOperands("r", &ops) || - !DoRestore( ops.register_number)) - return false; - break; - - // Save the current set of rules on a stack. - case DW_CFA_remember_state: - if (!saved_rules_) { - saved_rules_ = new std::stack<RuleMap>(); - } - saved_rules_->push(rules_); - break; - - // Pop the current set of rules off the stack. - case DW_CFA_restore_state: { - if (!saved_rules_ || saved_rules_->empty()) { - reporter_->EmptyStateStack(entry_->offset, entry_->kind, - CursorOffset()); - return false; - } - const RuleMap &new_rules = saved_rules_->top(); - if (rules_.CFARule() && !new_rules.CFARule()) { - reporter_->ClearingCFARule(entry_->offset, entry_->kind, - CursorOffset()); - return false; - } - rules_.HandleTransitionTo(handler_, address_, new_rules); - rules_ = new_rules; - saved_rules_->pop(); - break; - } - - // No operation. (Padding instruction.) - case DW_CFA_nop: - break; - - // A SPARC register window save: Registers 8 through 15 (%o0-%o7) - // are saved in registers 24 through 31 (%i0-%i7), and registers - // 16 through 31 (%l0-%l7 and %i0-%i7) are saved at CFA offsets - // (0-15 * the register size). The register numbers must be - // hard-coded. A GNU extension, and not a pretty one. - case DW_CFA_GNU_window_save: { - // Save %o0-%o7 in %i0-%i7. - for (int i = 8; i < 16; i++) - if (!DoRule(i, new RegisterRule(i + 16))) - return false; - // Save %l0-%l7 and %i0-%i7 at the CFA. - for (int i = 16; i < 32; i++) - // Assume that the byte reader's address size is the same as - // the architecture's register size. !@#%*^ hilarious. - if (!DoRule(i, new OffsetRule(Handler::kCFARegister, - (i - 16) * reader_->AddressSize()))) - return false; - break; - } - - // I'm not sure what this is. GDB doesn't use it for unwinding. - case DW_CFA_GNU_args_size: - if (!ParseOperands("o", &ops)) return false; - break; - - // An opcode we don't recognize. - default: { - reporter_->BadInstruction(entry_->offset, entry_->kind, CursorOffset()); - return false; - } - } - - return true; -} - -bool CallFrameInfo::State::DoDefCFA(unsigned base_register, long offset) { - Rule *rule = new ValOffsetRule(base_register, offset); - rules_.SetCFARule(rule); - return rule->Handle(handler_, address_, Handler::kCFARegister); -} - -bool CallFrameInfo::State::DoDefCFAOffset(long offset) { - Rule *cfa_rule = rules_.CFARule(); - if (!cfa_rule) { - reporter_->NoCFARule(entry_->offset, entry_->kind, CursorOffset()); - return false; - } - cfa_rule->SetOffset(offset); - return cfa_rule->Handle(handler_, address_, Handler::kCFARegister); -} - -bool CallFrameInfo::State::DoRule(unsigned reg, Rule *rule) { - rules_.SetRegisterRule(reg, rule); - return rule->Handle(handler_, address_, reg); -} - -bool CallFrameInfo::State::DoOffset(unsigned reg, long offset) { - if (!rules_.CFARule()) { - reporter_->NoCFARule(entry_->offset, entry_->kind, CursorOffset()); - return false; - } - return DoRule(reg, - new OffsetRule(Handler::kCFARegister, offset)); -} - -bool CallFrameInfo::State::DoValOffset(unsigned reg, long offset) { - if (!rules_.CFARule()) { - reporter_->NoCFARule(entry_->offset, entry_->kind, CursorOffset()); - return false; - } - return DoRule(reg, - new ValOffsetRule(Handler::kCFARegister, offset)); -} - -bool CallFrameInfo::State::DoRestore(unsigned reg) { - // DW_CFA_restore and DW_CFA_restore_extended don't make sense in a CIE. - if (entry_->kind == kCIE) { - reporter_->RestoreInCIE(entry_->offset, CursorOffset()); - return false; - } - Rule *rule = cie_rules_.RegisterRule(reg); - if (!rule) { - // This isn't really the right thing to do, but since CFI generally - // only mentions callee-saves registers, and GCC's convention for - // callee-saves registers is that they are unchanged, it's a good - // approximation. - rule = new SameValueRule(); - } - return DoRule(reg, rule); -} - -bool CallFrameInfo::ReadEntryPrologue(const char *cursor, Entry *entry) { - const char *buffer_end = buffer_ + buffer_length_; - - // Initialize enough of ENTRY for use in error reporting. - entry->offset = cursor - buffer_; - entry->start = cursor; - entry->kind = kUnknown; - entry->end = NULL; - - // Read the initial length. This sets reader_'s offset size. - size_t length_size; - uint64 length = reader_->ReadInitialLength(cursor, &length_size); - if (length_size > size_t(buffer_end - cursor)) - return ReportIncomplete(entry); - cursor += length_size; - - // In a .eh_frame section, a length of zero marks the end of the series - // of entries. - if (length == 0 && eh_frame_) { - entry->kind = kTerminator; - entry->end = cursor; - return true; - } - - // Validate the length. - if (length > size_t(buffer_end - cursor)) - return ReportIncomplete(entry); - - // The length is the number of bytes after the initial length field; - // we have that position handy at this point, so compute the end - // now. (If we're parsing 64-bit-offset DWARF on a 32-bit machine, - // and the length didn't fit in a size_t, we would have rejected it - // above.) - entry->end = cursor + length; - - // Parse the next field: either the offset of a CIE or a CIE id. - size_t offset_size = reader_->OffsetSize(); - if (offset_size > size_t(entry->end - cursor)) return ReportIncomplete(entry); - entry->id = reader_->ReadOffset(cursor); - - // Don't advance cursor past id field yet; in .eh_frame data we need - // the id's position to compute the section offset of an FDE's CIE. - - // Now we can decide what kind of entry this is. - if (eh_frame_) { - // In .eh_frame data, an ID of zero marks the entry as a CIE, and - // anything else is an offset from the id field of the FDE to the start - // of the CIE. - if (entry->id == 0) { - entry->kind = kCIE; - } else { - entry->kind = kFDE; - // Turn the offset from the id into an offset from the buffer's start. - entry->id = (cursor - buffer_) - entry->id; - } - } else { - // In DWARF CFI data, an ID of ~0 (of the appropriate width, given the - // offset size for the entry) marks the entry as a CIE, and anything - // else is the offset of the CIE from the beginning of the section. - if (offset_size == 4) - entry->kind = (entry->id == 0xffffffff) ? kCIE : kFDE; - else { - MOZ_ASSERT(offset_size == 8); - entry->kind = (entry->id == 0xffffffffffffffffULL) ? kCIE : kFDE; - } - } - - // Now advance cursor past the id. - cursor += offset_size; - - // The fields specific to this kind of entry start here. - entry->fields = cursor; - - entry->cie = NULL; - - return true; -} - -bool CallFrameInfo::ReadCIEFields(CIE *cie) { - const char *cursor = cie->fields; - size_t len; - - MOZ_ASSERT(cie->kind == kCIE); - - // Prepare for early exit. - cie->version = 0; - cie->augmentation.clear(); - cie->code_alignment_factor = 0; - cie->data_alignment_factor = 0; - cie->return_address_register = 0; - cie->has_z_augmentation = false; - cie->pointer_encoding = DW_EH_PE_absptr; - cie->instructions = 0; - - // Parse the version number. - if (cie->end - cursor < 1) - return ReportIncomplete(cie); - cie->version = reader_->ReadOneByte(cursor); - cursor++; - - // If we don't recognize the version, we can't parse any more fields of the - // CIE. For DWARF CFI, we handle versions 1 through 3 (there was never a - // version 2 of CFI data). For .eh_frame, we handle versions 1 and 3 as well; - // the difference between those versions seems to be the same as for - // .debug_frame. - if (cie->version < 1 || cie->version > 3) { - reporter_->UnrecognizedVersion(cie->offset, cie->version); - return false; - } - - const char *augmentation_start = cursor; - const void *augmentation_end = - memchr(augmentation_start, '\0', cie->end - augmentation_start); - if (! augmentation_end) return ReportIncomplete(cie); - cursor = static_cast<const char *>(augmentation_end); - cie->augmentation = string(augmentation_start, - cursor - augmentation_start); - // Skip the terminating '\0'. - cursor++; - - // Is this CFI augmented? - if (!cie->augmentation.empty()) { - // Is it an augmentation we recognize? - if (cie->augmentation[0] == DW_Z_augmentation_start) { - // Linux C++ ABI 'z' augmentation, used for exception handling data. - cie->has_z_augmentation = true; - } else { - // Not an augmentation we recognize. Augmentations can have arbitrary - // effects on the form of rest of the content, so we have to give up. - reporter_->UnrecognizedAugmentation(cie->offset, cie->augmentation); - return false; - } - } - - // Parse the code alignment factor. - cie->code_alignment_factor = reader_->ReadUnsignedLEB128(cursor, &len); - if (size_t(cie->end - cursor) < len) return ReportIncomplete(cie); - cursor += len; - - // Parse the data alignment factor. - cie->data_alignment_factor = reader_->ReadSignedLEB128(cursor, &len); - if (size_t(cie->end - cursor) < len) return ReportIncomplete(cie); - cursor += len; - - // Parse the return address register. This is a ubyte in version 1, and - // a ULEB128 in version 3. - if (cie->version == 1) { - if (cursor >= cie->end) return ReportIncomplete(cie); - cie->return_address_register = uint8(*cursor++); - } else { - cie->return_address_register = reader_->ReadUnsignedLEB128(cursor, &len); - if (size_t(cie->end - cursor) < len) return ReportIncomplete(cie); - cursor += len; - } - - // If we have a 'z' augmentation string, find the augmentation data and - // use the augmentation string to parse it. - if (cie->has_z_augmentation) { - uint64_t data_size = reader_->ReadUnsignedLEB128(cursor, &len); - if (size_t(cie->end - cursor) < len + data_size) - return ReportIncomplete(cie); - cursor += len; - const char *data = cursor; - cursor += data_size; - const char *data_end = cursor; - - cie->has_z_lsda = false; - cie->has_z_personality = false; - cie->has_z_signal_frame = false; - - // Walk the augmentation string, and extract values from the - // augmentation data as the string directs. - for (size_t i = 1; i < cie->augmentation.size(); i++) { - switch (cie->augmentation[i]) { - case DW_Z_has_LSDA: - // The CIE's augmentation data holds the language-specific data - // area pointer's encoding, and the FDE's augmentation data holds - // the pointer itself. - cie->has_z_lsda = true; - // Fetch the LSDA encoding from the augmentation data. - if (data >= data_end) return ReportIncomplete(cie); - cie->lsda_encoding = DwarfPointerEncoding(*data++); - if (!reader_->ValidEncoding(cie->lsda_encoding)) { - reporter_->InvalidPointerEncoding(cie->offset, cie->lsda_encoding); - return false; - } - // Don't check if the encoding is usable here --- we haven't - // read the FDE's fields yet, so we're not prepared for - // DW_EH_PE_funcrel, although that's a fine encoding for the - // LSDA to use, since it appears in the FDE. - break; - - case DW_Z_has_personality_routine: - // The CIE's augmentation data holds the personality routine - // pointer's encoding, followed by the pointer itself. - cie->has_z_personality = true; - // Fetch the personality routine pointer's encoding from the - // augmentation data. - if (data >= data_end) return ReportIncomplete(cie); - cie->personality_encoding = DwarfPointerEncoding(*data++); - if (!reader_->ValidEncoding(cie->personality_encoding)) { - reporter_->InvalidPointerEncoding(cie->offset, - cie->personality_encoding); - return false; - } - if (!reader_->UsableEncoding(cie->personality_encoding)) { - reporter_->UnusablePointerEncoding(cie->offset, - cie->personality_encoding); - return false; - } - // Fetch the personality routine's pointer itself from the data. - cie->personality_address = - reader_->ReadEncodedPointer(data, cie->personality_encoding, - &len); - if (len > size_t(data_end - data)) - return ReportIncomplete(cie); - data += len; - break; - - case DW_Z_has_FDE_address_encoding: - // The CIE's augmentation data holds the pointer encoding to use - // for addresses in the FDE. - if (data >= data_end) return ReportIncomplete(cie); - cie->pointer_encoding = DwarfPointerEncoding(*data++); - if (!reader_->ValidEncoding(cie->pointer_encoding)) { - reporter_->InvalidPointerEncoding(cie->offset, - cie->pointer_encoding); - return false; - } - if (!reader_->UsableEncoding(cie->pointer_encoding)) { - reporter_->UnusablePointerEncoding(cie->offset, - cie->pointer_encoding); - return false; - } - break; - - case DW_Z_is_signal_trampoline: - // Frames using this CIE are signal delivery frames. - cie->has_z_signal_frame = true; - break; - - default: - // An augmentation we don't recognize. - reporter_->UnrecognizedAugmentation(cie->offset, cie->augmentation); - return false; - } - } - } - - // The CIE's instructions start here. - cie->instructions = cursor; - - return true; -} - -bool CallFrameInfo::ReadFDEFields(FDE *fde) { - const char *cursor = fde->fields; - size_t size; - - fde->address = reader_->ReadEncodedPointer(cursor, fde->cie->pointer_encoding, - &size); - if (size > size_t(fde->end - cursor)) - return ReportIncomplete(fde); - cursor += size; - reader_->SetFunctionBase(fde->address); - - // For the length, we strip off the upper nybble of the encoding used for - // the starting address. - DwarfPointerEncoding length_encoding = - DwarfPointerEncoding(fde->cie->pointer_encoding & 0x0f); - fde->size = reader_->ReadEncodedPointer(cursor, length_encoding, &size); - if (size > size_t(fde->end - cursor)) - return ReportIncomplete(fde); - cursor += size; - - // If the CIE has a 'z' augmentation string, then augmentation data - // appears here. - if (fde->cie->has_z_augmentation) { - uint64_t data_size = reader_->ReadUnsignedLEB128(cursor, &size); - if (size_t(fde->end - cursor) < size + data_size) - return ReportIncomplete(fde); - cursor += size; - - // In the abstract, we should walk the augmentation string, and extract - // items from the FDE's augmentation data as we encounter augmentation - // string characters that specify their presence: the ordering of items - // in the augmentation string determines the arrangement of values in - // the augmentation data. - // - // In practice, there's only ever one value in FDE augmentation data - // that we support --- the LSDA pointer --- and we have to bail if we - // see any unrecognized augmentation string characters. So if there is - // anything here at all, we know what it is, and where it starts. - if (fde->cie->has_z_lsda) { - // Check whether the LSDA's pointer encoding is usable now: only once - // we've parsed the FDE's starting address do we call reader_-> - // SetFunctionBase, so that the DW_EH_PE_funcrel encoding becomes - // usable. - if (!reader_->UsableEncoding(fde->cie->lsda_encoding)) { - reporter_->UnusablePointerEncoding(fde->cie->offset, - fde->cie->lsda_encoding); - return false; - } - - fde->lsda_address = - reader_->ReadEncodedPointer(cursor, fde->cie->lsda_encoding, &size); - if (size > data_size) - return ReportIncomplete(fde); - // Ideally, we would also complain here if there were unconsumed - // augmentation data. - } - - cursor += data_size; - } - - // The FDE's instructions start after those. - fde->instructions = cursor; - - return true; -} - -bool CallFrameInfo::Start() { - const char *buffer_end = buffer_ + buffer_length_; - const char *cursor; - bool all_ok = true; - const char *entry_end; - bool ok; - - // Traverse all the entries in buffer_, skipping CIEs and offering - // FDEs to the handler. - for (cursor = buffer_; cursor < buffer_end; - cursor = entry_end, all_ok = all_ok && ok) { - FDE fde; - - // Make it easy to skip this entry with 'continue': assume that - // things are not okay until we've checked all the data, and - // prepare the address of the next entry. - ok = false; - - // Read the entry's prologue. - if (!ReadEntryPrologue(cursor, &fde)) { - if (!fde.end) { - // If we couldn't even figure out this entry's extent, then we - // must stop processing entries altogether. - all_ok = false; - break; - } - entry_end = fde.end; - continue; - } - - // The next iteration picks up after this entry. - entry_end = fde.end; - - // Did we see an .eh_frame terminating mark? - if (fde.kind == kTerminator) { - // If there appears to be more data left in the section after the - // terminating mark, warn the user. But this is just a warning; - // we leave all_ok true. - if (fde.end < buffer_end) reporter_->EarlyEHTerminator(fde.offset); - break; - } - - // In this loop, we skip CIEs. We only parse them fully when we - // parse an FDE that refers to them. This limits our memory - // consumption (beyond the buffer itself) to that needed to - // process the largest single entry. - if (fde.kind != kFDE) { - ok = true; - continue; - } - - // Validate the CIE pointer. - if (fde.id > buffer_length_) { - reporter_->CIEPointerOutOfRange(fde.offset, fde.id); - continue; - } - - CIE cie; - - // Parse this FDE's CIE header. - if (!ReadEntryPrologue(buffer_ + fde.id, &cie)) - continue; - // This had better be an actual CIE. - if (cie.kind != kCIE) { - reporter_->BadCIEId(fde.offset, fde.id); - continue; - } - if (!ReadCIEFields(&cie)) - continue; - - // We now have the values that govern both the CIE and the FDE. - cie.cie = &cie; - fde.cie = &cie; - - // Parse the FDE's header. - if (!ReadFDEFields(&fde)) - continue; - - // Call Entry to ask the consumer if they're interested. - if (!handler_->Entry(fde.offset, fde.address, fde.size, - cie.version, cie.augmentation, - cie.return_address_register)) { - // The handler isn't interested in this entry. That's not an error. - ok = true; - continue; - } - - if (cie.has_z_augmentation) { - // Report the personality routine address, if we have one. - if (cie.has_z_personality) { - if (!handler_ - ->PersonalityRoutine(cie.personality_address, - IsIndirectEncoding(cie.personality_encoding))) - continue; - } - - // Report the language-specific data area address, if we have one. - if (cie.has_z_lsda) { - if (!handler_ - ->LanguageSpecificDataArea(fde.lsda_address, - IsIndirectEncoding(cie.lsda_encoding))) - continue; - } - - // If this is a signal-handling frame, report that. - if (cie.has_z_signal_frame) { - if (!handler_->SignalHandler()) - continue; - } - } - - // Interpret the CIE's instructions, and then the FDE's instructions. - State state(reader_, handler_, reporter_, fde.address); - ok = state.InterpretCIE(cie) && state.InterpretFDE(fde); - - // Tell the ByteReader that the function start address from the - // FDE header is no longer valid. - reader_->ClearFunctionBase(); - - // Report the end of the entry. - handler_->End(); - } - - return all_ok; -} - -const char *CallFrameInfo::KindName(EntryKind kind) { - if (kind == CallFrameInfo::kUnknown) - return "entry"; - else if (kind == CallFrameInfo::kCIE) - return "common information entry"; - else if (kind == CallFrameInfo::kFDE) - return "frame description entry"; - else { - MOZ_ASSERT (kind == CallFrameInfo::kTerminator); - return ".eh_frame sequence terminator"; - } -} - -bool CallFrameInfo::ReportIncomplete(Entry *entry) { - reporter_->Incomplete(entry->offset, entry->kind); - return false; -} - -void CallFrameInfo::Reporter::Incomplete(uint64 offset, - CallFrameInfo::EntryKind kind) { - char buf[300]; - SprintfLiteral(buf, - "%s: CFI %s at offset 0x%llx in '%s': entry ends early\n", - filename_.c_str(), CallFrameInfo::KindName(kind), offset, - section_.c_str()); - log_(buf); -} - -void CallFrameInfo::Reporter::EarlyEHTerminator(uint64 offset) { - char buf[300]; - SprintfLiteral(buf, - "%s: CFI at offset 0x%llx in '%s': saw end-of-data marker" - " before end of section contents\n", - filename_.c_str(), offset, section_.c_str()); - log_(buf); -} - -void CallFrameInfo::Reporter::CIEPointerOutOfRange(uint64 offset, - uint64 cie_offset) { - char buf[300]; - SprintfLiteral(buf, - "%s: CFI frame description entry at offset 0x%llx in '%s':" - " CIE pointer is out of range: 0x%llx\n", - filename_.c_str(), offset, section_.c_str(), cie_offset); - log_(buf); -} - -void CallFrameInfo::Reporter::BadCIEId(uint64 offset, uint64 cie_offset) { - char buf[300]; - SprintfLiteral(buf, - "%s: CFI frame description entry at offset 0x%llx in '%s':" - " CIE pointer does not point to a CIE: 0x%llx\n", - filename_.c_str(), offset, section_.c_str(), cie_offset); - log_(buf); -} - -void CallFrameInfo::Reporter::UnrecognizedVersion(uint64 offset, int version) { - char buf[300]; - SprintfLiteral(buf, - "%s: CFI frame description entry at offset 0x%llx in '%s':" - " CIE specifies unrecognized version: %d\n", - filename_.c_str(), offset, section_.c_str(), version); - log_(buf); -} - -void CallFrameInfo::Reporter::UnrecognizedAugmentation(uint64 offset, - const string &aug) { - char buf[300]; - SprintfLiteral(buf, - "%s: CFI frame description entry at offset 0x%llx in '%s':" - " CIE specifies unrecognized augmentation: '%s'\n", - filename_.c_str(), offset, section_.c_str(), aug.c_str()); - log_(buf); -} - -void CallFrameInfo::Reporter::InvalidPointerEncoding(uint64 offset, - uint8 encoding) { - char buf[300]; - SprintfLiteral(buf, - "%s: CFI common information entry at offset 0x%llx in '%s':" - " 'z' augmentation specifies invalid pointer encoding: " - "0x%02x\n", - filename_.c_str(), offset, section_.c_str(), encoding); - log_(buf); -} - -void CallFrameInfo::Reporter::UnusablePointerEncoding(uint64 offset, - uint8 encoding) { - char buf[300]; - SprintfLiteral(buf, - "%s: CFI common information entry at offset 0x%llx in '%s':" - " 'z' augmentation specifies a pointer encoding for which" - " we have no base address: 0x%02x\n", - filename_.c_str(), offset, section_.c_str(), encoding); - log_(buf); -} - -void CallFrameInfo::Reporter::RestoreInCIE(uint64 offset, uint64 insn_offset) { - char buf[300]; - SprintfLiteral(buf, - "%s: CFI common information entry at offset 0x%llx in '%s':" - " the DW_CFA_restore instruction at offset 0x%llx" - " cannot be used in a common information entry\n", - filename_.c_str(), offset, section_.c_str(), insn_offset); - log_(buf); -} - -void CallFrameInfo::Reporter::BadInstruction(uint64 offset, - CallFrameInfo::EntryKind kind, - uint64 insn_offset) { - char buf[300]; - SprintfLiteral(buf, - "%s: CFI %s at offset 0x%llx in section '%s':" - " the instruction at offset 0x%llx is unrecognized\n", - filename_.c_str(), CallFrameInfo::KindName(kind), - offset, section_.c_str(), insn_offset); - log_(buf); -} - -void CallFrameInfo::Reporter::NoCFARule(uint64 offset, - CallFrameInfo::EntryKind kind, - uint64 insn_offset) { - char buf[300]; - SprintfLiteral(buf, - "%s: CFI %s at offset 0x%llx in section '%s':" - " the instruction at offset 0x%llx assumes that a CFA rule " - "has been set, but none has been set\n", - filename_.c_str(), CallFrameInfo::KindName(kind), offset, - section_.c_str(), insn_offset); - log_(buf); -} - -void CallFrameInfo::Reporter::EmptyStateStack(uint64 offset, - CallFrameInfo::EntryKind kind, - uint64 insn_offset) { - char buf[300]; - SprintfLiteral(buf, - "%s: CFI %s at offset 0x%llx in section '%s':" - " the DW_CFA_restore_state instruction at offset 0x%llx" - " should pop a saved state from the stack, but the stack " - "is empty\n", - filename_.c_str(), CallFrameInfo::KindName(kind), offset, - section_.c_str(), insn_offset); - log_(buf); -} - -void CallFrameInfo::Reporter::ClearingCFARule(uint64 offset, - CallFrameInfo::EntryKind kind, - uint64 insn_offset) { - char buf[300]; - SprintfLiteral(buf, - "%s: CFI %s at offset 0x%llx in section '%s':" - " the DW_CFA_restore_state instruction at offset 0x%llx" - " would clear the CFA rule in effect\n", - filename_.c_str(), CallFrameInfo::KindName(kind), offset, - section_.c_str(), insn_offset); - log_(buf); -} - - -unsigned int DwarfCFIToModule::RegisterNames::I386() { - /* - 8 "$eax", "$ecx", "$edx", "$ebx", "$esp", "$ebp", "$esi", "$edi", - 3 "$eip", "$eflags", "$unused1", - 8 "$st0", "$st1", "$st2", "$st3", "$st4", "$st5", "$st6", "$st7", - 2 "$unused2", "$unused3", - 8 "$xmm0", "$xmm1", "$xmm2", "$xmm3", "$xmm4", "$xmm5", "$xmm6", "$xmm7", - 8 "$mm0", "$mm1", "$mm2", "$mm3", "$mm4", "$mm5", "$mm6", "$mm7", - 3 "$fcw", "$fsw", "$mxcsr", - 8 "$es", "$cs", "$ss", "$ds", "$fs", "$gs", "$unused4", "$unused5", - 2 "$tr", "$ldtr" - */ - return 8 + 3 + 8 + 2 + 8 + 8 + 3 + 8 + 2; -} - -unsigned int DwarfCFIToModule::RegisterNames::X86_64() { - /* - 8 "$rax", "$rdx", "$rcx", "$rbx", "$rsi", "$rdi", "$rbp", "$rsp", - 8 "$r8", "$r9", "$r10", "$r11", "$r12", "$r13", "$r14", "$r15", - 1 "$rip", - 8 "$xmm0","$xmm1","$xmm2", "$xmm3", "$xmm4", "$xmm5", "$xmm6", "$xmm7", - 8 "$xmm8","$xmm9","$xmm10","$xmm11","$xmm12","$xmm13","$xmm14","$xmm15", - 8 "$st0", "$st1", "$st2", "$st3", "$st4", "$st5", "$st6", "$st7", - 8 "$mm0", "$mm1", "$mm2", "$mm3", "$mm4", "$mm5", "$mm6", "$mm7", - 1 "$rflags", - 8 "$es", "$cs", "$ss", "$ds", "$fs", "$gs", "$unused1", "$unused2", - 4 "$fs.base", "$gs.base", "$unused3", "$unused4", - 2 "$tr", "$ldtr", - 3 "$mxcsr", "$fcw", "$fsw" - */ - return 8 + 8 + 1 + 8 + 8 + 8 + 8 + 1 + 8 + 4 + 2 + 3; -} - -// Per ARM IHI 0040A, section 3.1 -unsigned int DwarfCFIToModule::RegisterNames::ARM() { - /* - 8 "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", - 8 "r8", "r9", "r10", "r11", "r12", "sp", "lr", "pc", - 8 "f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7", - 8 "fps", "cpsr", "", "", "", "", "", "", - 8 "", "", "", "", "", "", "", "", - 8 "", "", "", "", "", "", "", "", - 8 "", "", "", "", "", "", "", "", - 8 "", "", "", "", "", "", "", "", - 8 "s0", "s1", "s2", "s3", "s4", "s5", "s6", "s7", - 8 "s8", "s9", "s10", "s11", "s12", "s13", "s14", "s15", - 8 "s16", "s17", "s18", "s19", "s20", "s21", "s22", "s23", - 8 "s24", "s25", "s26", "s27", "s28", "s29", "s30", "s31", - 8 "f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7" - */ - return 13 * 8; -} - -// See prototype for comments. -int32_t parseDwarfExpr(Summariser* summ, const ByteReader* reader, - string expr, bool debug, - bool pushCfaAtStart, bool derefAtEnd) -{ - const char* cursor = expr.c_str(); - const char* end1 = cursor + expr.length(); - - char buf[100]; - if (debug) { - SprintfLiteral(buf, "LUL.DW << DwarfExpr, len is %d\n", - (int)(end1 - cursor)); - summ->Log(buf); - } - - // Add a marker for the start of this expression. In it, indicate - // whether or not the CFA should be pushed onto the stack prior to - // evaluation. - int32_t start_ix - = summ->AddPfxInstr(PfxInstr(PX_Start, pushCfaAtStart ? 1 : 0)); - MOZ_ASSERT(start_ix >= 0); - - while (cursor < end1) { - - uint8 opc = reader->ReadOneByte(cursor); - cursor++; - - const char* nm = nullptr; - PfxExprOp pxop = PX_End; - - switch (opc) { - - case DW_OP_lit0 ... DW_OP_lit31: { - int32_t simm32 = (int32_t)(opc - DW_OP_lit0); - if (debug) { - SprintfLiteral(buf, "LUL.DW DW_OP_lit%d\n", (int)simm32); - summ->Log(buf); - } - (void) summ->AddPfxInstr(PfxInstr(PX_SImm32, simm32)); - break; - } - - case DW_OP_breg0 ... DW_OP_breg31: { - size_t len; - int64_t n = reader->ReadSignedLEB128(cursor, &len); - cursor += len; - DW_REG_NUMBER reg = (DW_REG_NUMBER)(opc - DW_OP_breg0); - if (debug) { - SprintfLiteral(buf, "LUL.DW DW_OP_breg%d %lld\n", - (int)reg, (long long int)n); - summ->Log(buf); - } - // PfxInstr only allows a 32 bit signed offset. So we - // must fail if the immediate is out of range. - if (n < INT32_MIN || INT32_MAX < n) - goto fail; - (void) summ->AddPfxInstr(PfxInstr(PX_DwReg, reg)); - (void) summ->AddPfxInstr(PfxInstr(PX_SImm32, (int32_t)n)); - (void) summ->AddPfxInstr(PfxInstr(PX_Add)); - break; - } - - case DW_OP_const4s: { - uint64_t u64 = reader->ReadFourBytes(cursor); - cursor += 4; - // u64 is guaranteed by |ReadFourBytes| to be in the - // range 0 .. FFFFFFFF inclusive. But to be safe: - uint32_t u32 = (uint32_t)(u64 & 0xFFFFFFFF); - int32_t s32 = (int32_t)u32; - if (debug) { - SprintfLiteral(buf, "LUL.DW DW_OP_const4s %d\n", (int)s32); - summ->Log(buf); - } - (void) summ->AddPfxInstr(PfxInstr(PX_SImm32, s32)); - break; - } - - case DW_OP_deref: nm = "deref"; pxop = PX_Deref; goto no_operands; - case DW_OP_and: nm = "and"; pxop = PX_And; goto no_operands; - case DW_OP_plus: nm = "plus"; pxop = PX_Add; goto no_operands; - case DW_OP_minus: nm = "minus"; pxop = PX_Sub; goto no_operands; - case DW_OP_shl: nm = "shl"; pxop = PX_Shl; goto no_operands; - case DW_OP_ge: nm = "ge"; pxop = PX_CmpGES; goto no_operands; - no_operands: - MOZ_ASSERT(nm && pxop != PX_End); - if (debug) { - SprintfLiteral(buf, "LUL.DW DW_OP_%s\n", nm); - summ->Log(buf); - } - (void) summ->AddPfxInstr(PfxInstr(pxop)); - break; - - default: - if (debug) { - SprintfLiteral(buf, "LUL.DW unknown opc %d\n", (int)opc); - summ->Log(buf); - } - goto fail; - - } // switch (opc) - - } // while (cursor < end1) - - MOZ_ASSERT(cursor >= end1); - - if (cursor > end1) { - // We overran the Dwarf expression. Give up. - goto fail; - } - - // For DW_CFA_expression, what the expression denotes is the address - // of where the previous value is located. The caller of this routine - // may therefore request one last dereference before the end marker is - // inserted. - if (derefAtEnd) { - (void) summ->AddPfxInstr(PfxInstr(PX_Deref)); - } - - // Insert an end marker, and declare success. - (void) summ->AddPfxInstr(PfxInstr(PX_End)); - if (debug) { - SprintfLiteral(buf, "LUL.DW conversion of dwarf expression succeeded, " - "ix = %d\n", (int)start_ix); - summ->Log(buf); - summ->Log("LUL.DW >>\n"); - } - return start_ix; - - fail: - if (debug) { - summ->Log("LUL.DW conversion of dwarf expression failed\n"); - summ->Log("LUL.DW >>\n"); - } - return -1; -} - - -bool DwarfCFIToModule::Entry(size_t offset, uint64 address, uint64 length, - uint8 version, const string &augmentation, - unsigned return_address) { - if (DEBUG_DWARF) { - char buf[100]; - SprintfLiteral(buf, "LUL.DW DwarfCFIToModule::Entry 0x%llx,+%lld\n", - address, length); - summ_->Log(buf); - } - - summ_->Entry(address, length); - - // If dwarf2reader::CallFrameInfo can handle this version and - // augmentation, then we should be okay with that, so there's no - // need to check them here. - - // Get ready to collect entries. - return_address_ = return_address; - - // Breakpad STACK CFI records must provide a .ra rule, but DWARF CFI - // may not establish any rule for .ra if the return address column - // is an ordinary register, and that register holds the return - // address on entry to the function. So establish an initial .ra - // rule citing the return address register. - if (return_address_ < num_dw_regs_) { - summ_->Rule(address, return_address_, NODEREF, return_address, 0); - } - - return true; -} - -const UniqueString* DwarfCFIToModule::RegisterName(int i) { - if (i < 0) { - MOZ_ASSERT(i == kCFARegister); - return usu_->ToUniqueString(".cfa"); - } - unsigned reg = i; - if (reg == return_address_) - return usu_->ToUniqueString(".ra"); - - char buf[30]; - SprintfLiteral(buf, "dwarf_reg_%u", reg); - return usu_->ToUniqueString(buf); -} - -bool DwarfCFIToModule::UndefinedRule(uint64 address, int reg) { - reporter_->UndefinedNotSupported(entry_offset_, RegisterName(reg)); - // Treat this as a non-fatal error. - return true; -} - -bool DwarfCFIToModule::SameValueRule(uint64 address, int reg) { - if (DEBUG_DWARF) { - char buf[100]; - SprintfLiteral(buf, "LUL.DW 0x%llx: old r%d = Same\n", address, reg); - summ_->Log(buf); - } - // reg + 0 - summ_->Rule(address, reg, NODEREF, reg, 0); - return true; -} - -bool DwarfCFIToModule::OffsetRule(uint64 address, int reg, - int base_register, long offset) { - if (DEBUG_DWARF) { - char buf[100]; - SprintfLiteral(buf, "LUL.DW 0x%llx: old r%d = *(r%d + %ld)\n", - address, reg, base_register, offset); - summ_->Log(buf); - } - // *(base_register + offset) - summ_->Rule(address, reg, DEREF, base_register, offset); - return true; -} - -bool DwarfCFIToModule::ValOffsetRule(uint64 address, int reg, - int base_register, long offset) { - if (DEBUG_DWARF) { - char buf[100]; - SprintfLiteral(buf, "LUL.DW 0x%llx: old r%d = r%d + %ld\n", - address, reg, base_register, offset); - summ_->Log(buf); - } - // base_register + offset - summ_->Rule(address, reg, NODEREF, base_register, offset); - return true; -} - -bool DwarfCFIToModule::RegisterRule(uint64 address, int reg, - int base_register) { - if (DEBUG_DWARF) { - char buf[100]; - SprintfLiteral(buf, "LUL.DW 0x%llx: old r%d = r%d\n", - address, reg, base_register); - summ_->Log(buf); - } - // base_register + 0 - summ_->Rule(address, reg, NODEREF, base_register, 0); - return true; -} - -bool DwarfCFIToModule::ExpressionRule(uint64 address, int reg, - const string &expression) -{ - bool debug = !!DEBUG_DWARF; - int32_t start_ix = parseDwarfExpr(summ_, reader_, expression, debug, - true/*pushCfaAtStart*/, - true/*derefAtEnd*/); - if (start_ix >= 0) { - summ_->Rule(address, reg, PFXEXPR, 0, start_ix); - } else { - // Parsing of the Dwarf expression failed. Treat this as a - // non-fatal error, hence return |true| even on this path. - reporter_->ExpressionCouldNotBeSummarised(entry_offset_, RegisterName(reg)); - } - return true; -} - -bool DwarfCFIToModule::ValExpressionRule(uint64 address, int reg, - const string &expression) -{ - bool debug = !!DEBUG_DWARF; - int32_t start_ix = parseDwarfExpr(summ_, reader_, expression, debug, - true/*pushCfaAtStart*/, - false/*!derefAtEnd*/); - if (start_ix >= 0) { - summ_->Rule(address, reg, PFXEXPR, 0, start_ix); - } else { - // Parsing of the Dwarf expression failed. Treat this as a - // non-fatal error, hence return |true| even on this path. - reporter_->ExpressionCouldNotBeSummarised(entry_offset_, RegisterName(reg)); - } - return true; -} - -bool DwarfCFIToModule::End() { - //module_->AddStackFrameEntry(entry_); - if (DEBUG_DWARF) { - summ_->Log("LUL.DW DwarfCFIToModule::End()\n"); - } - summ_->End(); - return true; -} - -void DwarfCFIToModule::Reporter::UndefinedNotSupported( - size_t offset, - const UniqueString* reg) { - char buf[300]; - SprintfLiteral(buf, "DwarfCFIToModule::Reporter::UndefinedNotSupported()\n"); - log_(buf); - //BPLOG(INFO) << file_ << ", section '" << section_ - // << "': the call frame entry at offset 0x" - // << std::setbase(16) << offset << std::setbase(10) - // << " sets the rule for register '" << FromUniqueString(reg) - // << "' to 'undefined', but the Breakpad symbol file format cannot " - // << " express this"; -} - -// FIXME: move this somewhere sensible -static bool is_power_of_2(uint64_t n) -{ - int i, nSetBits = 0; - for (i = 0; i < 8*(int)sizeof(n); i++) { - if ((n & ((uint64_t)1) << i) != 0) - nSetBits++; - } - return nSetBits <= 1; -} - -void DwarfCFIToModule::Reporter::ExpressionCouldNotBeSummarised( - size_t offset, - const UniqueString* reg) { - static uint64_t n_complaints = 0; // This isn't threadsafe - n_complaints++; - if (!is_power_of_2(n_complaints)) - return; - char buf[300]; - SprintfLiteral(buf, - "DwarfCFIToModule::Reporter::" - "ExpressionCouldNotBeSummarised(shown %llu times)\n", - (unsigned long long int)n_complaints); - log_(buf); -} - -} // namespace lul |