// dwarf_reader.h -- parse dwarf2/3 debug information for gold -*- C++ -*-
-// Copyright 2007 Free Software Foundation, Inc.
+// Copyright 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.
// This file is part of gold.
#include <vector>
#include <map>
+#include <limits.h>
#include "elfcpp.h"
#include "elfcpp_swap.h"
#include "dwarf.h"
+#include "reloc.h"
namespace gold
{
class Track_relocs;
struct LineStateMachine;
+// 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)
+ // A pointer into files_.
+ unsigned int file_num : sizeof(int) * CHAR_BIT - 1;
+ // True if this was the last entry for the current offset, meaning
+ // it's the line that actually applies.
+ unsigned int last_line_for_offset : 1;
+ // The line number in the source file. -1 to indicate end-of-function.
+ int line_num;
+
+ // This sorts by offsets first, and then puts the correct line to
+ // report for a given offset at the beginning of the run of equal
+ // offsets (so that asking for 1 line gives the best answer). This
+ // is not a total ordering.
+ bool operator<(const Offset_to_lineno_entry& that) const
+ {
+ if (this->offset != that.offset)
+ return this->offset < that.offset;
+ // Note the '>' which makes this sort 'true' first.
+ return this->last_line_for_offset > that.last_line_for_offset;
+ }
+};
+
// This class is used to read the line information from the debugging
// section of an object file.
-template<int size, bool big_endian>
class Dwarf_line_info
{
public:
- // Initializes a .debug_line reader. Buffer and buffer length point
- // to the beginning and length of the line information to read.
- // Reader is a ByteReader class that has the endianness set
- // properly.
- Dwarf_line_info(const unsigned char* buffer, off_t buffer_length,
- Track_relocs<size, big_endian>* track_relocs,
- const unsigned char* symtab_buffer,
- off_t symtab_buffer_length)
- : data_valid_(true),
- buffer_(buffer), buffer_end_(buffer + buffer_length),
- track_relocs_(track_relocs),
- symtab_buffer_(symtab_buffer),
- symtab_buffer_end_(symtab_buffer + symtab_buffer_length),
- directories_(1), files_(1)
+ Dwarf_line_info()
{ }
- // Start processing line info, and populates the offset_map_.
- void
- read_line_mappings();
+ 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.
+ // read_line_mappings() before calling this function. If
+ // 'other_lines' is non-NULL, fills that in with other line
+ // numbers assigned to the same offset.
std::string
- addr2line(unsigned int shndx, off_t offset);
+ addr2line(unsigned int shndx, off_t offset,
+ std::vector<std::string>* other_lines)
+ { return this->do_addr2line(shndx, offset, other_lines); }
+
+ // 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, std::vector<std::string>* other_lines);
+
+ // 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,
+ std::vector<std::string>* other_lines) = 0;
+};
+
+template<int size, bool big_endian>
+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,
+ std::vector<std::string>* other_lines);
+
+ // Formats a file and line number to a string like "dirname/filename:lineno".
+ std::string
+ format_file_lineno(const Offset_to_lineno_entry& lineno) const;
+
+ // 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();
+ read_relocs(Object*);
// Looks in the symtab to see what section a symbol is in.
unsigned int
- symbol_section(unsigned int sym,
- typename elfcpp::Elf_types<size>::Elf_Addr* value);
+ symbol_section(Object*, unsigned int sym,
+ typename elfcpp::Elf_types<size>::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_tables(const unsigned char* lineptr);
- // Reads the DWARF2/3 line information.
+ // 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);
+ 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
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).
// 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* const buffer_end_;
+ const unsigned char* buffer_end_;
// This has relocations that point into buffer.
- Track_relocs<size, big_endian>* track_relocs_;
+ Track_relocs<size, big_endian> track_relocs_;
+ // The type of the reloc section in track_relocs_--SHT_REL or SHT_RELA.
+ unsigned int track_relocs_type_;
// This is used to figure out what section to apply a relocation to.
- const unsigned char* const symtab_buffer_;
- const unsigned char* const symtab_buffer_end_;
+ const unsigned char* symtab_buffer_;
+ section_size_type symtab_buffer_size_;
- // Holds the directories and files as we see them.
- std::vector<std::string> directories_;
+ // 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<std::vector<std::string> > directories_;
// The first part is an index into directories_, the second the filename.
- std::vector< std::pair<int, std::string> > files_;
+ std::vector<std::vector< std::pair<int, std::string> > > files_;
+
+ // An index into the current directories_ and files_ vectors.
+ int current_header_index_;
- // A map from offset of the relocation target to the shndx and
- // addend for the relocation.
+ // A sorted map from offset of the relocation target to the shndx
+ // and addend for the relocation.
typedef std::map<typename elfcpp::Elf_types<size>::Elf_Addr,
std::pair<unsigned int,
typename elfcpp::Elf_types<size>::Elf_Swxword> >
Reloc_map;
Reloc_map reloc_map_;
- // 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 file_num; // a pointer into files_
- int line_num;
- // 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; }
- };
// We have a vector of offset->lineno entries for every input section.
typedef Unordered_map<unsigned int, std::vector<Offset_to_lineno_entry> >
Lineno_map;
projects / deliverable / binutils-gdb.git / blobdiff