X-Git-Url: https://oss.titaniummirror.com/gitweb?p=msp430-binutils.git;a=blobdiff_plain;f=gold%2Fdwarf_reader.h;fp=gold%2Fdwarf_reader.h;h=c18ed8951b0312139710cb2288089921bc24a1f0;hp=0000000000000000000000000000000000000000;hb=88750007d7869f178f0ba528f41efd3b74c424cf;hpb=6df9443a374e2b81278c61b8afc0a1eef7db280b diff --git a/gold/dwarf_reader.h b/gold/dwarf_reader.h new file mode 100644 index 0000000..c18ed89 --- /dev/null +++ b/gold/dwarf_reader.h @@ -0,0 +1,219 @@ +// dwarf_reader.h -- parse dwarf2/3 debug information for gold -*- C++ -*- + +// Copyright 2007, 2008, 2009 Free Software Foundation, Inc. +// Written by Ian Lance Taylor . + +// 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_DWARF_READER_H +#define GOLD_DWARF_READER_H + +#include +#include + +#include "elfcpp.h" +#include "elfcpp_swap.h" +#include "dwarf.h" +#include "reloc.h" + +namespace gold +{ + +template +class Track_relocs; +struct LineStateMachine; + +uint64_t +read_unsigned_LEB_128(const unsigned char* buffer, size_t* len); + +int64_t +read_signed_LEB_128(const unsigned char* buffer, size_t* len); + +// We can't do better than to keep the offsets in a sorted vector. +// Here, offset is the key, and file_num/line_num is the value. +struct Offset_to_lineno_entry +{ + off_t offset; + int header_num; // which file-list to use (i.e. which .o file are we in) + int file_num; // a pointer into files_ + int line_num; // the line number in the source file + // Offsets are unique within a section, so that's a sufficient sort key. + bool operator<(const Offset_to_lineno_entry& that) const + { return this->offset < that.offset; } +}; + +// This class is used to read the line information from the debugging +// section of an object file. + +class Dwarf_line_info +{ + public: + Dwarf_line_info() + { } + + virtual + ~Dwarf_line_info() + { } + + // Given a section number and an offset, returns the associated + // file and line-number, as a string: "file:lineno". If unable + // to do the mapping, returns the empty string. You must call + // read_line_mappings() before calling this function. + std::string + addr2line(unsigned int shndx, off_t offset) + { return do_addr2line(shndx, offset); } + + // A helper function for a single addr2line lookup. It also keeps a + // cache of the last CACHE_SIZE Dwarf_line_info objects it created; + // set to 0 not to cache at all. The larger CACHE_SIZE is, the more + // chance this routine won't have to re-create a Dwarf_line_info + // object for its addr2line computation; such creations are slow. + // NOTE: Not thread-safe, so only call from one thread at a time. + static std::string + one_addr2line(Object* object, unsigned int shndx, off_t offset, + size_t cache_size); + + // This reclaims all the memory that one_addr2line may have cached. + // Use this when you know you will not be calling one_addr2line again. + static void + clear_addr2line_cache(); + + private: + virtual std::string + do_addr2line(unsigned int shndx, off_t offset) = 0; +}; + +template +class Sized_dwarf_line_info : public Dwarf_line_info +{ + public: + // Initializes a .debug_line reader for a given object file. + // If SHNDX is specified and non-negative, only read the debug + // information that pertains to the specified section. + Sized_dwarf_line_info(Object* object, unsigned int read_shndx = -1U); + + private: + std::string + do_addr2line(unsigned int shndx, off_t offset); + + // Start processing line info, and populates the offset_map_. + // If SHNDX is non-negative, only store debug information that + // pertains to the specified section. + void + read_line_mappings(Object*, unsigned int shndx); + + // Reads the relocation section associated with .debug_line and + // stores relocation information in reloc_map_. + void + read_relocs(Object*); + + // Looks in the symtab to see what section a symbol is in. + unsigned int + symbol_section(Object*, unsigned int sym, + typename elfcpp::Elf_types::Elf_Addr* value, + bool* is_ordinary); + + // Reads the DWARF2/3 header for this line info. Each takes as input + // a starting buffer position, and returns the ending position. + const unsigned char* + read_header_prolog(const unsigned char* lineptr); + + const unsigned char* + read_header_tables(const unsigned char* lineptr); + + // Reads the DWARF2/3 line information. If shndx is non-negative, + // discard all line information that doesn't pertain to the given + // section. + const unsigned char* + read_lines(const unsigned char* lineptr, unsigned int shndx); + + // Process a single line info opcode at START using the state + // machine at LSM. Return true if we should define a line using the + // current state of the line state machine. Place the length of the + // opcode in LEN. + bool + process_one_opcode(const unsigned char* start, + struct LineStateMachine* lsm, size_t* len); + + // Some parts of processing differ depending on whether the input + // was a .o file or not. + bool input_is_relobj(); + + // If we saw anything amiss while parsing, we set this to false. + // Then addr2line will always fail (rather than return possibly- + // corrupt data). + bool data_valid_; + + // A DWARF2/3 line info header. This is not the same size as in the + // actual file, as the one in the file may have a 32 bit or 64 bit + // lengths. + + struct Dwarf_line_infoHeader + { + off_t total_length; + int version; + off_t prologue_length; + int min_insn_length; // insn stands for instructin + bool default_is_stmt; // stmt stands for statement + signed char line_base; + int line_range; + unsigned char opcode_base; + std::vector std_opcode_lengths; + int offset_size; + } header_; + + // buffer is the buffer for our line info, starting at exactly where + // the line info to read is. + const unsigned char* buffer_; + const unsigned char* buffer_end_; + + // This has relocations that point into buffer. + Track_relocs track_relocs_; + + // This is used to figure out what section to apply a relocation to. + const unsigned char* symtab_buffer_; + section_size_type symtab_buffer_size_; + + // Holds the directories and files as we see them. We have an array + // of directory-lists, one for each .o file we're reading (usually + // there will just be one, but there may be more if input is a .so). + std::vector > directories_; + // The first part is an index into directories_, the second the filename. + std::vector > > files_; + + // An index into the current directories_ and files_ vectors. + int current_header_index_; + + // A sorted map from offset of the relocation target to the shndx + // and addend for the relocation. + typedef std::map::Elf_Addr, + std::pair::Elf_Swxword> > + Reloc_map; + Reloc_map reloc_map_; + + // We have a vector of offset->lineno entries for every input section. + typedef Unordered_map > + Lineno_map; + + Lineno_map line_number_map_; +}; + +} // End namespace gold. + +#endif // !defined(GOLD_DWARF_READER_H)