1086 lines
32 KiB
C++
1086 lines
32 KiB
C++
// symtab.h -- the gold symbol table -*- C++ -*-
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// Symbol_table
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// The symbol table.
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#include <string>
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#include <utility>
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#include <vector>
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#include "elfcpp.h"
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#include "parameters.h"
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#include "stringpool.h"
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#include "object.h"
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#ifndef GOLD_SYMTAB_H
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#define GOLD_SYMTAB_H
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namespace gold
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{
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class Object;
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class Relobj;
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template<int size, bool big_endian>
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class Sized_relobj;
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class Dynobj;
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template<int size, bool big_endian>
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class Sized_dynobj;
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class Versions;
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class Output_data;
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class Output_section;
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class Output_segment;
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class Output_file;
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class Target;
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// The base class of an entry in the symbol table. The symbol table
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// can have a lot of entries, so we don't want this class to big.
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// Size dependent fields can be found in the template class
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// Sized_symbol. Targets may support their own derived classes.
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class Symbol
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{
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public:
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// Because we want the class to be small, we don't use any virtual
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// functions. But because symbols can be defined in different
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// places, we need to classify them. This enum is the different
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// sources of symbols we support.
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enum Source
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{
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// Symbol defined in a relocatable or dynamic input file--this is
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// the most common case.
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FROM_OBJECT,
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// Symbol defined in an Output_data, a special section created by
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// the target.
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IN_OUTPUT_DATA,
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// Symbol defined in an Output_segment, with no associated
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// section.
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IN_OUTPUT_SEGMENT,
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// Symbol value is constant.
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CONSTANT
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};
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// When the source is IN_OUTPUT_SEGMENT, we need to describe what
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// the offset means.
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enum Segment_offset_base
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{
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// From the start of the segment.
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SEGMENT_START,
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// From the end of the segment.
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SEGMENT_END,
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// From the filesz of the segment--i.e., after the loaded bytes
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// but before the bytes which are allocated but zeroed.
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SEGMENT_BSS
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};
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// Return the symbol name.
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const char*
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name() const
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{ return this->name_; }
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// Return the symbol version. This will return NULL for an
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// unversioned symbol.
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const char*
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version() const
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{ return this->version_; }
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// Return the symbol source.
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Source
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source() const
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{ return this->source_; }
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// Return the object with which this symbol is associated.
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Object*
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object() const
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{
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gold_assert(this->source_ == FROM_OBJECT);
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return this->u_.from_object.object;
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}
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// Return the index of the section in the input relocatable or
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// dynamic object file.
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unsigned int
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shndx() const
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{
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gold_assert(this->source_ == FROM_OBJECT);
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return this->u_.from_object.shndx;
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}
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// Return the output data section with which this symbol is
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// associated, if the symbol was specially defined with respect to
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// an output data section.
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Output_data*
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output_data() const
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{
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gold_assert(this->source_ == IN_OUTPUT_DATA);
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return this->u_.in_output_data.output_data;
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}
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// If this symbol was defined with respect to an output data
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// section, return whether the value is an offset from end.
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bool
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offset_is_from_end() const
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{
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gold_assert(this->source_ == IN_OUTPUT_DATA);
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return this->u_.in_output_data.offset_is_from_end;
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}
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// Return the output segment with which this symbol is associated,
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// if the symbol was specially defined with respect to an output
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// segment.
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Output_segment*
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output_segment() const
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{
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gold_assert(this->source_ == IN_OUTPUT_SEGMENT);
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return this->u_.in_output_segment.output_segment;
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}
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// If this symbol was defined with respect to an output segment,
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// return the offset base.
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Segment_offset_base
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offset_base() const
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{
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gold_assert(this->source_ == IN_OUTPUT_SEGMENT);
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return this->u_.in_output_segment.offset_base;
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}
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// Return the symbol binding.
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elfcpp::STB
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binding() const
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{ return this->binding_; }
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// Return the symbol type.
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elfcpp::STT
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type() const
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{ return this->type_; }
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// Return the symbol visibility.
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elfcpp::STV
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visibility() const
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{ return this->visibility_; }
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// Return the non-visibility part of the st_other field.
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unsigned char
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nonvis() const
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{ return this->nonvis_; }
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// Return whether this symbol is a forwarder. This will never be
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// true of a symbol found in the hash table, but may be true of
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// symbol pointers attached to object files.
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bool
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is_forwarder() const
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{ return this->is_forwarder_; }
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// Mark this symbol as a forwarder.
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void
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set_forwarder()
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{ this->is_forwarder_ = true; }
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// Return whether this symbol needs an entry in the dynamic symbol
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// table.
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bool
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needs_dynsym_entry() const
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{
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return (this->needs_dynsym_entry_
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|| (this->in_reg() && this->in_dyn()));
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}
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// Mark this symbol as needing an entry in the dynamic symbol table.
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void
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set_needs_dynsym_entry()
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{ this->needs_dynsym_entry_ = true; }
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// Return whether this symbol has been seen in a regular object.
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bool
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in_reg() const
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{ return this->in_reg_; }
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// Mark this symbol as having been seen in a regular object.
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void
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set_in_reg()
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{ this->in_reg_ = true; }
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// Return whether this symbol has been seen in a dynamic object.
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bool
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in_dyn() const
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{ return this->in_dyn_; }
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// Mark this symbol as having been seen in a dynamic object.
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void
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set_in_dyn()
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{ this->in_dyn_ = true; }
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// Return the index of this symbol in the output file symbol table.
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// A value of -1U means that this symbol is not going into the
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// output file. This starts out as zero, and is set to a non-zero
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// value by Symbol_table::finalize. It is an error to ask for the
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// symbol table index before it has been set.
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unsigned int
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symtab_index() const
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{
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gold_assert(this->symtab_index_ != 0);
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return this->symtab_index_;
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}
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// Set the index of the symbol in the output file symbol table.
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void
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set_symtab_index(unsigned int index)
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{
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gold_assert(index != 0);
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this->symtab_index_ = index;
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}
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// Return whether this symbol already has an index in the output
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// file symbol table.
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bool
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has_symtab_index() const
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{ return this->symtab_index_ != 0; }
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// Return the index of this symbol in the dynamic symbol table. A
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// value of -1U means that this symbol is not going into the dynamic
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// symbol table. This starts out as zero, and is set to a non-zero
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// during Layout::finalize. It is an error to ask for the dynamic
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// symbol table index before it has been set.
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unsigned int
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dynsym_index() const
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{
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gold_assert(this->dynsym_index_ != 0);
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return this->dynsym_index_;
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}
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// Set the index of the symbol in the dynamic symbol table.
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void
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set_dynsym_index(unsigned int index)
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{
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gold_assert(index != 0);
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this->dynsym_index_ = index;
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}
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// Return whether this symbol already has an index in the dynamic
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// symbol table.
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bool
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has_dynsym_index() const
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{ return this->dynsym_index_ != 0; }
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// Return whether this symbol has an entry in the GOT section.
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bool
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has_got_offset() const
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{ return this->has_got_offset_; }
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// Return the offset into the GOT section of this symbol.
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unsigned int
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got_offset() const
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{
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gold_assert(this->has_got_offset());
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return this->got_offset_;
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}
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// Set the GOT offset of this symbol.
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void
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set_got_offset(unsigned int got_offset)
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{
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this->has_got_offset_ = true;
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this->got_offset_ = got_offset;
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}
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// Return whether this symbol has an entry in the PLT section.
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bool
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has_plt_offset() const
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{ return this->has_plt_offset_; }
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// Return the offset into the PLT section of this symbol.
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unsigned int
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plt_offset() const
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{
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gold_assert(this->has_plt_offset());
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return this->plt_offset_;
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}
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// Set the PLT offset of this symbol.
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void
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set_plt_offset(unsigned int plt_offset)
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{
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this->has_plt_offset_ = true;
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this->plt_offset_ = plt_offset;
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}
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// Return true if the final value of this symbol is known at link
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// time.
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bool
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final_value_is_known() const
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{
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if (parameters->output_is_shared())
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return false;
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return this->source_ != FROM_OBJECT || !this->object()->is_dynamic();
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}
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// Return whether this is a defined symbol (not undefined or
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// common).
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bool
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is_defined() const
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{
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return (this->source_ != FROM_OBJECT
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|| (this->shndx() != elfcpp::SHN_UNDEF
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&& this->shndx() != elfcpp::SHN_COMMON));
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}
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// Return true if this symbol is from a dynamic object.
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bool
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is_from_dynobj() const
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{
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return this->source_ == FROM_OBJECT && this->object()->is_dynamic();
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}
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// Return whether this is an undefined symbol.
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bool
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is_undefined() const
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{
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return this->source_ == FROM_OBJECT && this->shndx() == elfcpp::SHN_UNDEF;
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}
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// Return whether this is a common symbol.
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bool
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is_common() const
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{
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return (this->source_ == FROM_OBJECT
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&& (this->shndx() == elfcpp::SHN_COMMON
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|| this->type_ == elfcpp::STT_COMMON));
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}
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// Return whether this symbol can be seen outside this object.
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bool
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is_externally_visible() const
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{
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return (this->visibility_ == elfcpp::STV_DEFAULT
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|| this->visibility_ == elfcpp::STV_PROTECTED);
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}
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// Return whether there should be a warning for references to this
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// symbol.
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bool
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has_warning() const
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{ return this->has_warning_; }
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// Mark this symbol as having a warning.
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void
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set_has_warning()
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{ this->has_warning_ = true; }
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protected:
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// Instances of this class should always be created at a specific
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// size.
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Symbol()
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{ memset(this, 0, sizeof *this); }
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// Initialize the general fields.
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void
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init_fields(const char* name, const char* version,
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elfcpp::STT type, elfcpp::STB binding,
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elfcpp::STV visibility, unsigned char nonvis);
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// Initialize fields from an ELF symbol in OBJECT.
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template<int size, bool big_endian>
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void
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init_base(const char *name, const char* version, Object* object,
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const elfcpp::Sym<size, big_endian>&);
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// Initialize fields for an Output_data.
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void
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init_base(const char* name, Output_data*, elfcpp::STT, elfcpp::STB,
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elfcpp::STV, unsigned char nonvis, bool offset_is_from_end);
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// Initialize fields for an Output_segment.
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void
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init_base(const char* name, Output_segment* os, elfcpp::STT type,
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elfcpp::STB binding, elfcpp::STV visibility,
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unsigned char nonvis, Segment_offset_base offset_base);
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// Initialize fields for a constant.
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void
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init_base(const char* name, elfcpp::STT type, elfcpp::STB binding,
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elfcpp::STV visibility, unsigned char nonvis);
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// Override existing symbol.
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template<int size, bool big_endian>
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void
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override_base(const elfcpp::Sym<size, big_endian>&, Object* object,
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const char* version);
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// Override existing symbol with a special symbol.
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void
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override_base_with_special(const Symbol* from);
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private:
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Symbol(const Symbol&);
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Symbol& operator=(const Symbol&);
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// Symbol name (expected to point into a Stringpool).
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const char* name_;
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// Symbol version (expected to point into a Stringpool). This may
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// be NULL.
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const char* version_;
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union
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{
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// This struct is used if SOURCE_ == FROM_OBJECT.
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struct
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{
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// Object in which symbol is defined, or in which it was first
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// seen.
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Object* object;
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// Section number in object_ in which symbol is defined.
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unsigned int shndx;
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} from_object;
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// This struct is used if SOURCE_ == IN_OUTPUT_DATA.
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struct
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{
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// Output_data in which symbol is defined. Before
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// Layout::finalize the symbol's value is an offset within the
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// Output_data.
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Output_data* output_data;
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// True if the offset is from the end, false if the offset is
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// from the beginning.
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bool offset_is_from_end;
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} in_output_data;
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// This struct is used if SOURCE_ == IN_OUTPUT_SEGMENT.
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struct
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{
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// Output_segment in which the symbol is defined. Before
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// Layout::finalize the symbol's value is an offset.
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Output_segment* output_segment;
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// The base to use for the offset before Layout::finalize.
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Segment_offset_base offset_base;
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} in_output_segment;
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} u_;
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// The index of this symbol in the output file. If the symbol is
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// not going into the output file, this value is -1U. This field
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// starts as always holding zero. It is set to a non-zero value by
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// Symbol_table::finalize.
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unsigned int symtab_index_;
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// The index of this symbol in the dynamic symbol table. If the
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// symbol is not going into the dynamic symbol table, this value is
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// -1U. This field starts as always holding zero. It is set to a
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// non-zero value during Layout::finalize.
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unsigned int dynsym_index_;
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// If this symbol has an entry in the GOT section (has_got_offset_
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// is true), this is the offset from the start of the GOT section.
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unsigned int got_offset_;
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// If this symbol has an entry in the PLT section (has_plt_offset_
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// is true), then this is the offset from the start of the PLT
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// section.
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unsigned int plt_offset_;
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// Symbol type.
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elfcpp::STT type_ : 4;
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// Symbol binding.
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elfcpp::STB binding_ : 4;
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// Symbol visibility.
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elfcpp::STV visibility_ : 2;
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// Rest of symbol st_other field.
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unsigned int nonvis_ : 6;
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// The type of symbol.
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Source source_ : 3;
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// True if this symbol always requires special target-specific
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// handling.
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bool is_target_special_ : 1;
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// True if this is the default version of the symbol.
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bool is_def_ : 1;
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// True if this symbol really forwards to another symbol. This is
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// used when we discover after the fact that two different entries
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// in the hash table really refer to the same symbol. This will
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// never be set for a symbol found in the hash table, but may be set
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// for a symbol found in the list of symbols attached to an Object.
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// It forwards to the symbol found in the forwarders_ map of
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// Symbol_table.
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bool is_forwarder_ : 1;
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// True if this symbol needs to be in the dynamic symbol table.
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bool needs_dynsym_entry_ : 1;
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// True if we've seen this symbol in a regular object.
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bool in_reg_ : 1;
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// True if we've seen this symbol in a dynamic object.
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bool in_dyn_ : 1;
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// True if the symbol has an entry in the GOT section.
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bool has_got_offset_ : 1;
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// True if the symbol has an entry in the PLT section.
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bool has_plt_offset_ : 1;
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// True if there is a warning for this symbol.
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bool has_warning_ : 1;
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};
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// The parts of a symbol which are size specific. Using a template
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// derived class like this helps us use less space on a 32-bit system.
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template<int size>
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class Sized_symbol : public Symbol
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{
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public:
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typedef typename elfcpp::Elf_types<size>::Elf_Addr Value_type;
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typedef typename elfcpp::Elf_types<size>::Elf_WXword Size_type;
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Sized_symbol()
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{ }
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// Initialize fields from an ELF symbol in OBJECT.
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template<bool big_endian>
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void
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init(const char *name, const char* version, Object* object,
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const elfcpp::Sym<size, big_endian>&);
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// Initialize fields for an Output_data.
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void
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init(const char* name, Output_data*, Value_type value, Size_type symsize,
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elfcpp::STT, elfcpp::STB, elfcpp::STV, unsigned char nonvis,
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bool offset_is_from_end);
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// Initialize fields for an Output_segment.
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void
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init(const char* name, Output_segment*, Value_type value, Size_type symsize,
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elfcpp::STT, elfcpp::STB, elfcpp::STV, unsigned char nonvis,
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Segment_offset_base offset_base);
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|
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// Initialize fields for a constant.
|
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void
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init(const char* name, Value_type value, Size_type symsize,
|
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elfcpp::STT, elfcpp::STB, elfcpp::STV, unsigned char nonvis);
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|
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// Override existing symbol.
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template<bool big_endian>
|
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void
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override(const elfcpp::Sym<size, big_endian>&, Object* object,
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const char* version);
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|
|
|
// Override existing symbol with a special symbol.
|
|
void
|
|
override_with_special(const Sized_symbol<size>*);
|
|
|
|
// Return the symbol's value.
|
|
Value_type
|
|
value() const
|
|
{ return this->value_; }
|
|
|
|
// Return the symbol's size (we can't call this 'size' because that
|
|
// is a template parameter).
|
|
Size_type
|
|
symsize() const
|
|
{ return this->symsize_; }
|
|
|
|
// Set the symbol size. This is used when resolving common symbols.
|
|
void
|
|
set_symsize(Size_type symsize)
|
|
{ this->symsize_ = symsize; }
|
|
|
|
// Set the symbol value. This is called when we store the final
|
|
// values of the symbols into the symbol table.
|
|
void
|
|
set_value(Value_type value)
|
|
{ this->value_ = value; }
|
|
|
|
private:
|
|
Sized_symbol(const Sized_symbol&);
|
|
Sized_symbol& operator=(const Sized_symbol&);
|
|
|
|
// Symbol value. Before Layout::finalize this is the offset in the
|
|
// input section. This is set to the final value during
|
|
// Layout::finalize.
|
|
Value_type value_;
|
|
// Symbol size.
|
|
Size_type symsize_;
|
|
};
|
|
|
|
// A struct describing a symbol defined by the linker, where the value
|
|
// of the symbol is defined based on an output section. This is used
|
|
// for symbols defined by the linker, like "_init_array_start".
|
|
|
|
struct Define_symbol_in_section
|
|
{
|
|
// The symbol name.
|
|
const char* name;
|
|
// The name of the output section with which this symbol should be
|
|
// associated. If there is no output section with that name, the
|
|
// symbol will be defined as zero.
|
|
const char* output_section;
|
|
// The offset of the symbol within the output section. This is an
|
|
// offset from the start of the output section, unless start_at_end
|
|
// is true, in which case this is an offset from the end of the
|
|
// output section.
|
|
uint64_t value;
|
|
// The size of the symbol.
|
|
uint64_t size;
|
|
// The symbol type.
|
|
elfcpp::STT type;
|
|
// The symbol binding.
|
|
elfcpp::STB binding;
|
|
// The symbol visibility.
|
|
elfcpp::STV visibility;
|
|
// The rest of the st_other field.
|
|
unsigned char nonvis;
|
|
// If true, the value field is an offset from the end of the output
|
|
// section.
|
|
bool offset_is_from_end;
|
|
// If true, this symbol is defined only if we see a reference to it.
|
|
bool only_if_ref;
|
|
};
|
|
|
|
// A struct describing a symbol defined by the linker, where the value
|
|
// of the symbol is defined based on a segment. This is used for
|
|
// symbols defined by the linker, like "_end". We describe the
|
|
// segment with which the symbol should be associated by its
|
|
// characteristics. If no segment meets these characteristics, the
|
|
// symbol will be defined as zero. If there is more than one segment
|
|
// which meets these characteristics, we will use the first one.
|
|
|
|
struct Define_symbol_in_segment
|
|
{
|
|
// The symbol name.
|
|
const char* name;
|
|
// The segment type where the symbol should be defined, typically
|
|
// PT_LOAD.
|
|
elfcpp::PT segment_type;
|
|
// Bitmask of segment flags which must be set.
|
|
elfcpp::PF segment_flags_set;
|
|
// Bitmask of segment flags which must be clear.
|
|
elfcpp::PF segment_flags_clear;
|
|
// The offset of the symbol within the segment. The offset is
|
|
// calculated from the position set by offset_base.
|
|
uint64_t value;
|
|
// The size of the symbol.
|
|
uint64_t size;
|
|
// The symbol type.
|
|
elfcpp::STT type;
|
|
// The symbol binding.
|
|
elfcpp::STB binding;
|
|
// The symbol visibility.
|
|
elfcpp::STV visibility;
|
|
// The rest of the st_other field.
|
|
unsigned char nonvis;
|
|
// The base from which we compute the offset.
|
|
Symbol::Segment_offset_base offset_base;
|
|
// If true, this symbol is defined only if we see a reference to it.
|
|
bool only_if_ref;
|
|
};
|
|
|
|
// This class manages warnings. Warnings are a GNU extension. When
|
|
// we see a section named .gnu.warning.SYM in an object file, and if
|
|
// we wind using the definition of SYM from that object file, then we
|
|
// will issue a warning for any relocation against SYM from a
|
|
// different object file. The text of the warning is the contents of
|
|
// the section. This is not precisely the definition used by the old
|
|
// GNU linker; the old GNU linker treated an occurrence of
|
|
// .gnu.warning.SYM as defining a warning symbol. A warning symbol
|
|
// would trigger a warning on any reference. However, it was
|
|
// inconsistent in that a warning in a dynamic object only triggered
|
|
// if there was no definition in a regular object. This linker is
|
|
// different in that we only issue a warning if we use the symbol
|
|
// definition from the same object file as the warning section.
|
|
|
|
class Warnings
|
|
{
|
|
public:
|
|
Warnings()
|
|
: warnings_()
|
|
{ }
|
|
|
|
// Add a warning for symbol NAME in section SHNDX in object OBJ.
|
|
void
|
|
add_warning(Symbol_table* symtab, const char* name, Object* obj,
|
|
unsigned int shndx);
|
|
|
|
// For each symbol for which we should give a warning, make a note
|
|
// on the symbol.
|
|
void
|
|
note_warnings(Symbol_table* symtab);
|
|
|
|
// Issue a warning for a reference to SYM at LOCATION.
|
|
void
|
|
issue_warning(const Symbol* sym, const std::string& location) const;
|
|
|
|
private:
|
|
Warnings(const Warnings&);
|
|
Warnings& operator=(const Warnings&);
|
|
|
|
// What we need to know to get the warning text.
|
|
struct Warning_location
|
|
{
|
|
// The object the warning is in.
|
|
Object* object;
|
|
// The index of the warning section.
|
|
unsigned int shndx;
|
|
// The warning text if we have already loaded it.
|
|
std::string text;
|
|
|
|
Warning_location()
|
|
: object(NULL), shndx(0), text()
|
|
{ }
|
|
|
|
void
|
|
set(Object* o, unsigned int s)
|
|
{
|
|
this->object = o;
|
|
this->shndx = s;
|
|
}
|
|
|
|
void
|
|
set_text(const char* t, off_t l)
|
|
{ this->text.assign(t, l); }
|
|
};
|
|
|
|
// A mapping from warning symbol names (canonicalized in
|
|
// Symbol_table's namepool_ field) to
|
|
typedef Unordered_map<const char*, Warning_location> Warning_table;
|
|
|
|
Warning_table warnings_;
|
|
};
|
|
|
|
// The main linker symbol table.
|
|
|
|
class Symbol_table
|
|
{
|
|
public:
|
|
Symbol_table();
|
|
|
|
~Symbol_table();
|
|
|
|
// Add COUNT external symbols from the relocatable object RELOBJ to
|
|
// the symbol table. SYMS is the symbols, SYM_NAMES is their names,
|
|
// SYM_NAME_SIZE is the size of SYM_NAMES. This sets SYMPOINTERS to
|
|
// point to the symbols in the symbol table.
|
|
template<int size, bool big_endian>
|
|
void
|
|
add_from_relobj(Sized_relobj<size, big_endian>* relobj,
|
|
const unsigned char* syms, size_t count,
|
|
const char* sym_names, size_t sym_name_size,
|
|
Symbol** sympointers);
|
|
|
|
// Add COUNT dynamic symbols from the dynamic object DYNOBJ to the
|
|
// symbol table. SYMS is the symbols. SYM_NAMES is their names.
|
|
// SYM_NAME_SIZE is the size of SYM_NAMES. The other parameters are
|
|
// symbol version data.
|
|
template<int size, bool big_endian>
|
|
void
|
|
add_from_dynobj(Sized_dynobj<size, big_endian>* dynobj,
|
|
const unsigned char* syms, size_t count,
|
|
const char* sym_names, size_t sym_name_size,
|
|
const unsigned char* versym, size_t versym_size,
|
|
const std::vector<const char*>*);
|
|
|
|
// Define a special symbol based on an Output_data. It is a
|
|
// multiple definition error if this symbol is already defined.
|
|
Symbol*
|
|
define_in_output_data(const Target*, const char* name, const char* version,
|
|
Output_data*, uint64_t value, uint64_t symsize,
|
|
elfcpp::STT type, elfcpp::STB binding,
|
|
elfcpp::STV visibility, unsigned char nonvis,
|
|
bool offset_is_from_end, bool only_if_ref);
|
|
|
|
// Define a special symbol based on an Output_segment. It is a
|
|
// multiple definition error if this symbol is already defined.
|
|
Symbol*
|
|
define_in_output_segment(const Target*, const char* name,
|
|
const char* version, Output_segment*,
|
|
uint64_t value, uint64_t symsize,
|
|
elfcpp::STT type, elfcpp::STB binding,
|
|
elfcpp::STV visibility, unsigned char nonvis,
|
|
Symbol::Segment_offset_base, bool only_if_ref);
|
|
|
|
// Define a special symbol with a constant value. It is a multiple
|
|
// definition error if this symbol is already defined.
|
|
Symbol*
|
|
define_as_constant(const Target*, const char* name, const char* version,
|
|
uint64_t value, uint64_t symsize, elfcpp::STT type,
|
|
elfcpp::STB binding, elfcpp::STV visibility,
|
|
unsigned char nonvis, bool only_if_ref);
|
|
|
|
// Define a set of symbols in output sections.
|
|
void
|
|
define_symbols(const Layout*, const Target*, int count,
|
|
const Define_symbol_in_section*);
|
|
|
|
// Define a set of symbols in output segments.
|
|
void
|
|
define_symbols(const Layout*, const Target*, int count,
|
|
const Define_symbol_in_segment*);
|
|
|
|
// Look up a symbol.
|
|
Symbol*
|
|
lookup(const char*, const char* version = NULL) const;
|
|
|
|
// Return the real symbol associated with the forwarder symbol FROM.
|
|
Symbol*
|
|
resolve_forwards(const Symbol* from) const;
|
|
|
|
// Return the bitsize (32 or 64) of the symbols in the table.
|
|
int
|
|
get_size() const
|
|
{ return this->size_; }
|
|
|
|
// Return the sized version of a symbol in this table.
|
|
template<int size>
|
|
Sized_symbol<size>*
|
|
get_sized_symbol(Symbol* ACCEPT_SIZE) const;
|
|
|
|
template<int size>
|
|
const Sized_symbol<size>*
|
|
get_sized_symbol(const Symbol* ACCEPT_SIZE) const;
|
|
|
|
// Return the count of undefined symbols seen.
|
|
int
|
|
saw_undefined() const
|
|
{ return this->saw_undefined_; }
|
|
|
|
// Allocate the common symbols
|
|
void
|
|
allocate_commons(const General_options&, Layout*);
|
|
|
|
// Add a warning for symbol NAME in section SHNDX in object OBJ.
|
|
void
|
|
add_warning(const char* name, Object* obj, unsigned int shndx)
|
|
{ this->warnings_.add_warning(this, name, obj, shndx); }
|
|
|
|
// Canonicalize a symbol name for use in the hash table.
|
|
const char*
|
|
canonicalize_name(const char* name)
|
|
{ return this->namepool_.add(name, NULL); }
|
|
|
|
// Possibly issue a warning for a reference to SYM at LOCATION which
|
|
// is in OBJ.
|
|
void
|
|
issue_warning(const Symbol* sym, const std::string& location) const
|
|
{ this->warnings_.issue_warning(sym, location); }
|
|
|
|
// Set the dynamic symbol indexes. INDEX is the index of the first
|
|
// global dynamic symbol. Pointers to the symbols are stored into
|
|
// the vector. The names are stored into the Stringpool. This
|
|
// returns an updated dynamic symbol index.
|
|
unsigned int
|
|
set_dynsym_indexes(const General_options*, const Target*, unsigned int index,
|
|
std::vector<Symbol*>*, Stringpool*, Versions*);
|
|
|
|
// Finalize the symbol table after we have set the final addresses
|
|
// of all the input sections. This sets the final symbol indexes,
|
|
// values and adds the names to *POOL. INDEX is the index of the
|
|
// first global symbol. OFF is the file offset of the global symbol
|
|
// table, DYNOFF is the offset of the globals in the dynamic symbol
|
|
// table, DYN_GLOBAL_INDEX is the index of the first global dynamic
|
|
// symbol, and DYNCOUNT is the number of global dynamic symbols.
|
|
// This records the parameters, and returns the new file offset.
|
|
off_t
|
|
finalize(unsigned int index, off_t off, off_t dynoff,
|
|
size_t dyn_global_index, size_t dyncount, Stringpool* pool);
|
|
|
|
// Write out the global symbols.
|
|
void
|
|
write_globals(const Target*, const Stringpool*, const Stringpool*,
|
|
Output_file*) const;
|
|
|
|
// Write out a section symbol. Return the updated offset.
|
|
void
|
|
write_section_symbol(const Target*, const Output_section*, Output_file*,
|
|
off_t) const;
|
|
|
|
private:
|
|
Symbol_table(const Symbol_table&);
|
|
Symbol_table& operator=(const Symbol_table&);
|
|
|
|
// Set the size (32 or 64) of the symbols in the table.
|
|
void
|
|
set_size(int size)
|
|
{ this->size_ = size; }
|
|
|
|
// Make FROM a forwarder symbol to TO.
|
|
void
|
|
make_forwarder(Symbol* from, Symbol* to);
|
|
|
|
// Add a symbol.
|
|
template<int size, bool big_endian>
|
|
Symbol*
|
|
add_from_object(Object*, const char *name, Stringpool::Key name_key,
|
|
const char *version, Stringpool::Key version_key,
|
|
bool def, const elfcpp::Sym<size, big_endian>& sym);
|
|
|
|
// Resolve symbols.
|
|
template<int size, bool big_endian>
|
|
static void
|
|
resolve(Sized_symbol<size>* to,
|
|
const elfcpp::Sym<size, big_endian>& sym,
|
|
Object*, const char* version);
|
|
|
|
template<int size, bool big_endian>
|
|
static void
|
|
resolve(Sized_symbol<size>* to, const Sized_symbol<size>* from,
|
|
const char* version ACCEPT_SIZE_ENDIAN);
|
|
|
|
// Whether we should override a symbol, based on flags in
|
|
// resolve.cc.
|
|
static bool
|
|
should_override(const Symbol*, unsigned int, bool*);
|
|
|
|
// Whether we should override a symbol with a special symbol which
|
|
// is automatically defined by the linker.
|
|
static bool
|
|
should_override_with_special(const Symbol*);
|
|
|
|
// Define a special symbol.
|
|
template<int size, bool big_endian>
|
|
Sized_symbol<size>*
|
|
define_special_symbol(const Target* target, const char* name,
|
|
const char* version, bool only_if_ref,
|
|
Sized_symbol<size>** poldsym ACCEPT_SIZE_ENDIAN);
|
|
|
|
// Define a symbol in an Output_data, sized version.
|
|
template<int size>
|
|
Sized_symbol<size>*
|
|
do_define_in_output_data(const Target*, const char* name,
|
|
const char* version, Output_data*,
|
|
typename elfcpp::Elf_types<size>::Elf_Addr value,
|
|
typename elfcpp::Elf_types<size>::Elf_WXword ssize,
|
|
elfcpp::STT type, elfcpp::STB binding,
|
|
elfcpp::STV visibility, unsigned char nonvis,
|
|
bool offset_is_from_end, bool only_if_ref);
|
|
|
|
// Define a symbol in an Output_segment, sized version.
|
|
template<int size>
|
|
Sized_symbol<size>*
|
|
do_define_in_output_segment(
|
|
const Target*, const char* name, const char* version, Output_segment* os,
|
|
typename elfcpp::Elf_types<size>::Elf_Addr value,
|
|
typename elfcpp::Elf_types<size>::Elf_WXword ssize,
|
|
elfcpp::STT type, elfcpp::STB binding,
|
|
elfcpp::STV visibility, unsigned char nonvis,
|
|
Symbol::Segment_offset_base offset_base, bool only_if_ref);
|
|
|
|
// Define a symbol as a constant, sized version.
|
|
template<int size>
|
|
Sized_symbol<size>*
|
|
do_define_as_constant(
|
|
const Target*, const char* name, const char* version,
|
|
typename elfcpp::Elf_types<size>::Elf_Addr value,
|
|
typename elfcpp::Elf_types<size>::Elf_WXword ssize,
|
|
elfcpp::STT type, elfcpp::STB binding,
|
|
elfcpp::STV visibility, unsigned char nonvis,
|
|
bool only_if_ref);
|
|
|
|
// Allocate the common symbols, sized version.
|
|
template<int size>
|
|
void
|
|
do_allocate_commons(const General_options&, Layout*);
|
|
|
|
// Finalize symbols specialized for size.
|
|
template<int size>
|
|
off_t
|
|
sized_finalize(unsigned int, off_t, Stringpool*);
|
|
|
|
// Write globals specialized for size and endianness.
|
|
template<int size, bool big_endian>
|
|
void
|
|
sized_write_globals(const Target*, const Stringpool*, const Stringpool*,
|
|
Output_file*) const;
|
|
|
|
// Write out a symbol to P.
|
|
template<int size, bool big_endian>
|
|
void
|
|
sized_write_symbol(Sized_symbol<size>*, unsigned int shndx,
|
|
const Stringpool*, unsigned char* p
|
|
ACCEPT_SIZE_ENDIAN) const;
|
|
|
|
// Write out a section symbol, specialized for size and endianness.
|
|
template<int size, bool big_endian>
|
|
void
|
|
sized_write_section_symbol(const Output_section*, Output_file*, off_t) const;
|
|
|
|
// The type of the symbol hash table.
|
|
|
|
typedef std::pair<Stringpool::Key, Stringpool::Key> Symbol_table_key;
|
|
|
|
struct Symbol_table_hash
|
|
{
|
|
size_t
|
|
operator()(const Symbol_table_key&) const;
|
|
};
|
|
|
|
struct Symbol_table_eq
|
|
{
|
|
bool
|
|
operator()(const Symbol_table_key&, const Symbol_table_key&) const;
|
|
};
|
|
|
|
typedef Unordered_map<Symbol_table_key, Symbol*, Symbol_table_hash,
|
|
Symbol_table_eq> Symbol_table_type;
|
|
|
|
// The type of the list of common symbols.
|
|
|
|
typedef std::vector<Symbol*> Commons_type;
|
|
|
|
// The size of the symbols in the symbol table (32 or 64).
|
|
int size_;
|
|
|
|
// We increment this every time we see a new undefined symbol, for
|
|
// use in archive groups.
|
|
int saw_undefined_;
|
|
|
|
// The index of the first global symbol in the output file.
|
|
unsigned int first_global_index_;
|
|
|
|
// The file offset within the output symtab section where we should
|
|
// write the table.
|
|
off_t offset_;
|
|
|
|
// The number of global symbols we want to write out.
|
|
size_t output_count_;
|
|
|
|
// The file offset of the global dynamic symbols, or 0 if none.
|
|
off_t dynamic_offset_;
|
|
|
|
// The index of the first global dynamic symbol.
|
|
unsigned int first_dynamic_global_index_;
|
|
|
|
// The number of global dynamic symbols, or 0 if none.
|
|
off_t dynamic_count_;
|
|
|
|
// The symbol hash table.
|
|
Symbol_table_type table_;
|
|
|
|
// A pool of symbol names. This is used for all global symbols.
|
|
// Entries in the hash table point into this pool.
|
|
Stringpool namepool_;
|
|
|
|
// Forwarding symbols.
|
|
Unordered_map<const Symbol*, Symbol*> forwarders_;
|
|
|
|
// We don't expect there to be very many common symbols, so we keep
|
|
// a list of them. When we find a common symbol we add it to this
|
|
// list. It is possible that by the time we process the list the
|
|
// symbol is no longer a common symbol. It may also have become a
|
|
// forwarder.
|
|
Commons_type commons_;
|
|
|
|
// Manage symbol warnings.
|
|
Warnings warnings_;
|
|
};
|
|
|
|
// We inline get_sized_symbol for efficiency.
|
|
|
|
template<int size>
|
|
Sized_symbol<size>*
|
|
Symbol_table::get_sized_symbol(Symbol* sym ACCEPT_SIZE) const
|
|
{
|
|
gold_assert(size == this->get_size());
|
|
return static_cast<Sized_symbol<size>*>(sym);
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|
}
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|
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template<int size>
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|
const Sized_symbol<size>*
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|
Symbol_table::get_sized_symbol(const Symbol* sym ACCEPT_SIZE) const
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|
{
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|
gold_assert(size == this->get_size());
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|
return static_cast<const Sized_symbol<size>*>(sym);
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|
}
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|
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} // End namespace gold.
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#endif // !defined(GOLD_SYMTAB_H)
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