/
githubmirror
/
binutils-gold
Обзор
Документация
Войти
/
githubmirror
/
binutils-gold
Код
Запросы
0
Пакеты
0
Релизы
0
Аналитика
Безопасность
v2.39
gold/int_encoding.h
158 строк
5 KB
Ziyao
Import source from binutils
18 сен 2022, 18:55
18 сен 2022, 18:55
3605144
Код
Авторство
О чём код?
// int_encoding.h -- variable length and unaligned integers -*- C++ -*- // Copyright (C) 2009-2022 Free Software Foundation, Inc. // Written by Doug Kwan <dougkwan@google.com> by refactoring scattered // contents from other files in gold. Original code written by Ian // Lance Taylor <iant@google.com> and Caleb Howe <cshowe@google.com>. // This file is part of gold. // This program is free software; you can redistribute it and/or modify // it under the terms of the GNU General Public License as published by // the Free Software Foundation; either version 3 of the License, or // (at your option) any later version. // This program is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // You should have received a copy of the GNU General Public License // along with this program; if not, write to the Free Software // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, // MA 02110-1301, USA. #ifndef GOLD_INT_ENCODING_H #define GOLD_INT_ENCODING_H #include <vector> #include "elfcpp.h" #include "target.h" #include "parameters.h" namespace gold { // // LEB 128 encoding support. // // Read a ULEB 128 encoded integer from BUFFER. Return the length of the // encoded integer at the location PLEN. The common case of a single-byte // value is handled inline, and multi-byte values are processed by the _x // routine, where BYTE is the first byte of the value. uint64_t read_unsigned_LEB_128_x(const unsigned char* buffer, size_t* plen, unsigned char byte); inline uint64_t read_unsigned_LEB_128(const unsigned char* buffer, size_t* plen) { unsigned char byte = *buffer++; if ((byte & 0x80) != 0) return read_unsigned_LEB_128_x(buffer, plen, byte); *plen = 1; return static_cast<uint64_t>(byte); } // Read an SLEB 128 encoded integer from BUFFER. Return the length of the // encoded integer at the location PLEN. The common case of a single-byte // value is handled inline, and multi-byte values are processed by the _x // routine, where BYTE is the first byte of the value. int64_t read_signed_LEB_128_x(const unsigned char* buffer, size_t* plen, unsigned char byte); inline int64_t read_signed_LEB_128(const unsigned char* buffer, size_t* plen) { unsigned char byte = *buffer++; if ((byte & 0x80) != 0) return read_signed_LEB_128_x(buffer, plen, byte); *plen = 1; if (byte & 0x40) return -(static_cast<int64_t>(1) << 7) | static_cast<int64_t>(byte); return static_cast<int64_t>(byte); } // Write a ULEB 128 encoded VALUE to BUFFER. void write_unsigned_LEB_128(std::vector<unsigned char>* buffer, uint64_t value); // Return the ULEB 128 encoded size of VALUE. size_t get_length_as_unsigned_LEB_128(uint64_t value); // // Unaligned integer encoding support. // // Insert VALSIZE-bit integer VALUE into DESTINATION. template <int valsize> void insert_into_vector(std::vector<unsigned char>* destination, typename elfcpp::Valtype_base<valsize>::Valtype value) { unsigned char buffer[valsize / 8]; if (parameters->target().is_big_endian()) elfcpp::Swap_unaligned<valsize, true>::writeval(buffer, value); else elfcpp::Swap_unaligned<valsize, false>::writeval(buffer, value); destination->insert(destination->end(), buffer, buffer + valsize / 8); } // Read a possibly unaligned integer of SIZE from SOURCE. template <int valsize> typename elfcpp::Valtype_base<valsize>::Valtype read_from_pointer(const unsigned char* source) { typename elfcpp::Valtype_base<valsize>::Valtype return_value; if (parameters->target().is_big_endian()) return_value = elfcpp::Swap_unaligned<valsize, true>::readval(source); else return_value = elfcpp::Swap_unaligned<valsize, false>::readval(source); return return_value; } // Read a possibly unaligned integer of SIZE. Update SOURCE after read. template <int valsize> typename elfcpp::Valtype_base<valsize>::Valtype read_from_pointer(unsigned char** source) { typename elfcpp::Valtype_base<valsize>::Valtype return_value; if (parameters->target().is_big_endian()) return_value = elfcpp::Swap_unaligned<valsize, true>::readval(*source); else return_value = elfcpp::Swap_unaligned<valsize, false>::readval(*source); *source += valsize / 8; return return_value; } // Same as the above except for use with const unsigned char data. template <int valsize> typename elfcpp::Valtype_base<valsize>::Valtype read_from_pointer(const unsigned char** source) { typename elfcpp::Valtype_base<valsize>::Valtype return_value; if (parameters->target().is_big_endian()) return_value = elfcpp::Swap_unaligned<valsize, true>::readval(*source); else return_value = elfcpp::Swap_unaligned<valsize, false>::readval(*source); *source += valsize / 8; return return_value; } } // End namespace gold. #endif // !defined(GOLD_INT_ENCODING_H)