// merge.h -- handle section merging for gold -*- C++ -*-
-// Copyright 2006, 2007, 2008 Free Software Foundation, Inc.
+// Copyright (C) 2006-2020 Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.
// This file is part of gold.
namespace gold
{
-class Merge_map;
-
// For each object with merge sections, we store an Object_merge_map.
// This is used to map locations in input sections to a merged output
// section. The output section itself is not recorded here--it can be
{
public:
Object_merge_map()
- : first_shnum_(-1U), first_map_(),
- second_shnum_(-1U), second_map_(),
- section_merge_maps_()
+ : section_merge_maps_()
{ }
~Object_merge_map();
// discarded. OUTPUT_OFFSET is relative to the start of the merged
// data in the output section.
void
- add_mapping(const Merge_map*, unsigned int shndx, section_offset_type offset,
- section_size_type length, section_offset_type output_offset);
+ add_mapping(const Output_section_data*, unsigned int shndx,
+ section_offset_type offset, section_size_type length,
+ section_offset_type output_offset);
// Get the output offset for an input address. MERGE_MAP is the map
// we are looking for, or NULL if we don't care. The input address
// mapping is known, false otherwise. *OUTPUT_OFFSET is relative to
// the start of the merged data in the output section.
bool
- get_output_offset(const Merge_map*, unsigned int shndx,
+ get_output_offset(unsigned int shndx,
section_offset_type offset,
- section_offset_type *output_offset);
+ section_offset_type* output_offset);
- // Return whether this is the merge map for section SHNDX.
- bool
- is_merge_section_for(const Merge_map*, unsigned int shndx);
+ const Output_section_data*
+ find_merge_section(unsigned int shndx) const;
// Initialize an mapping from input offsets to output addresses for
// section SHNDX. STARTING_ADDRESS is the output address of the
Unordered_map<section_offset_type,
typename elfcpp::Elf_types<size>::Elf_Addr>*);
- private:
// Map input section offsets to a length and an output section
// offset. An output section offset of -1 means that this part of
// the input section is being discarded.
section_offset_type output_offset;
};
- // A less-than comparison routine for Input_merge_entry.
- struct Input_merge_compare
- {
- bool
- operator()(const Input_merge_entry& i1, const Input_merge_entry& i2) const
- { return i1.input_offset < i2.input_offset; }
- };
-
// A list of entries for a particular input section.
struct Input_merge_map
{
+ void add_mapping(section_offset_type input_offset, section_size_type length,
+ section_offset_type output_offset);
+
typedef std::vector<Input_merge_entry> Entries;
// We store these with the Relobj, and we look them up by input
// look up information for a different Merge_map, we report that
// we don't have it, rather than trying a lookup and returning an
// answer which will receive the wrong offset.
- const Merge_map* merge_map;
+ const Output_section_data* output_data;
// The list of mappings.
Entries entries;
// Whether the ENTRIES field is sorted by input_offset.
bool sorted;
Input_merge_map()
- : merge_map(NULL), entries(), sorted(true)
+ : output_data(NULL), entries(), sorted(true)
{ }
};
- // Map input section indices to merge maps.
- typedef std::map<unsigned int, Input_merge_map*> Section_merge_maps;
-
- // Return a pointer to the Input_merge_map to use for the input
- // section SHNDX, or NULL.
- Input_merge_map*
- get_input_merge_map(unsigned int shndx);
-
- // Get or make the the Input_merge_map to use for the section SHNDX
+ // Get or make the Input_merge_map to use for the section SHNDX
// with MERGE_MAP.
Input_merge_map*
- get_or_make_input_merge_map(const Merge_map* merge_map, unsigned int shndx);
-
- // Any given object file will normally only have a couple of input
- // sections with mergeable contents. So we keep the first two input
- // section numbers inline, and push any further ones into a map. A
- // value of -1U in first_shnum_ or second_shnum_ means that we don't
- // have a corresponding entry.
- unsigned int first_shnum_;
- Input_merge_map first_map_;
- unsigned int second_shnum_;
- Input_merge_map second_map_;
- Section_merge_maps section_merge_maps_;
-};
+ get_or_make_input_merge_map(const Output_section_data* merge_map,
+ unsigned int shndx);
-// This class manages mappings from input sections to offsets in an
-// output section. This is used where input sections are merged. The
-// actual data is stored in fields in Object.
+ private:
+ // A less-than comparison routine for Input_merge_entry.
+ struct Input_merge_compare
+ {
+ bool
+ operator()(const Input_merge_entry& i1, const Input_merge_entry& i2) const
+ { return i1.input_offset < i2.input_offset; }
+ };
-class Merge_map
-{
- public:
- Merge_map()
- { }
+ // Map input section indices to merge maps.
+ typedef std::vector<std::pair<unsigned int, Input_merge_map*> >
+ Section_merge_maps;
- // Add a mapping for the bytes from OFFSET to OFFSET + LENGTH in the
- // input section SHNDX in object OBJECT to OUTPUT_OFFSET in the
- // output section. An OUTPUT_OFFSET of -1 means that the bytes are
- // discarded. OUTPUT_OFFSET is not the offset from the start of the
- // output section, it is the offset from the start of the merged
- // data within the output section.
- void
- add_mapping(Relobj* object, unsigned int shndx,
- section_offset_type offset, section_size_type length,
- section_offset_type output_offset);
-
- // Return the output offset for an input address. The input address
- // is at offset OFFSET in section SHNDX in OBJECT. This sets
- // *OUTPUT_OFFSET to the offset in the output section; this will be
- // -1 if the bytes are not being copied to the output. This returns
- // true if the mapping is known, false otherwise. This returns the
- // value stored by add_mapping, namely the offset from the start of
- // the merged data within the output section.
- bool
- get_output_offset(const Relobj* object, unsigned int shndx,
- section_offset_type offset,
- section_offset_type *output_offset) const;
+ // Return a pointer to the Input_merge_map to use for the input
+ // section SHNDX, or NULL.
+ const Input_merge_map*
+ get_input_merge_map(unsigned int shndx) const;
- // Return whether this is the merge mapping for section SHNDX in
- // OBJECT. This should return true when get_output_offset would
- // return true for some input offset.
- bool
- is_merge_section_for(const Relobj* object, unsigned int shndx) const;
+ Input_merge_map *
+ get_input_merge_map(unsigned int shndx) {
+ return const_cast<Input_merge_map *>(static_cast<const Object_merge_map *>(
+ this)->get_input_merge_map(shndx));
+ }
+
+ Section_merge_maps section_merge_maps_;
};
// A general class for SHF_MERGE data, to hold functions shared by
{
public:
Output_merge_base(uint64_t entsize, uint64_t addralign)
- : Output_section_data(addralign), merge_map_(), entsize_(entsize)
+ : Output_section_data(addralign), entsize_(entsize),
+ keeps_input_sections_(false), first_relobj_(NULL), first_shndx_(-1),
+ input_sections_()
{ }
// Return the entry size.
is_string()
{ return this->do_is_string(); }
+ // Whether this keeps input sections.
+ bool
+ keeps_input_sections() const
+ { return this->keeps_input_sections_; }
+
+ // Set the keeps-input-sections flag. This is virtual so that sub-classes
+ // can perform additional checks.
+ void
+ set_keeps_input_sections()
+ { this->do_set_keeps_input_sections(); }
+
+ // Return the object of the first merged input section. This used
+ // for script processing. This is NULL if merge section is empty.
+ Relobj*
+ first_relobj() const
+ { return this->first_relobj_; }
+
+ // Return the section index of the first merged input section. This
+ // is used for script processing. This is valid only if merge section
+ // is not valid.
+ unsigned int
+ first_shndx() const
+ {
+ gold_assert(this->first_relobj_ != NULL);
+ return this->first_shndx_;
+ }
+
+ // Set of merged input sections.
+ typedef Unordered_set<Section_id, Section_id_hash> Input_sections;
+
+ // Beginning of merged input sections.
+ Input_sections::const_iterator
+ input_sections_begin() const
+ {
+ gold_assert(this->keeps_input_sections_);
+ return this->input_sections_.begin();
+ }
+
+ // Beginning of merged input sections.
+ Input_sections::const_iterator
+ input_sections_end() const
+ {
+ gold_assert(this->keeps_input_sections_);
+ return this->input_sections_.end();
+ }
+
protected:
// Return the output offset for an input offset.
bool
section_offset_type offset,
section_offset_type* poutput) const;
- // Return whether this is the merge section for an input section.
- bool
- do_is_merge_section_for(const Relobj*, unsigned int shndx) const;
-
- // Add a mapping from an OFFSET in input section SHNDX in object
- // OBJECT to an OUTPUT_OFFSET in the output section. OUTPUT_OFFSET
- // is the offset from the start of the merged data in the output
- // section.
- void
- add_mapping(Relobj* object, unsigned int shndx, section_offset_type offset,
- section_size_type length, section_offset_type output_offset)
- {
- this->merge_map_.add_mapping(object, shndx, offset, length, output_offset);
- }
-
- // This may be overriden by the child class.
+ // This may be overridden by the child class.
virtual bool
do_is_string()
{ return false; }
+ // This may be overridden by the child class.
+ virtual void
+ do_set_keeps_input_sections()
+ { this->keeps_input_sections_ = true; }
+
+ // Record the merged input section for script processing.
+ void
+ record_input_section(Relobj* relobj, unsigned int shndx);
+
private:
- // A mapping from input object/section/offset to offset in output
- // section.
- Merge_map merge_map_;
// The entry size. For fixed-size constants, this is the size of
// the constants. For strings, this is the size of a character.
uint64_t entsize_;
+ // Whether we keep input sections.
+ bool keeps_input_sections_;
+ // Object of the first merged input section. We use this for script
+ // processing.
+ Relobj* first_relobj_;
+ // Section index of the first merged input section.
+ unsigned int first_shndx_;
+ // Input sections. We only keep them is keeps_input_sections_ is true.
+ Input_sections input_sections_;
};
// Handle SHF_MERGE sections with fixed-size constant data.
void
do_print_merge_stats(const char* section_name);
+ // Set keeps-input-sections flag.
+ void
+ do_set_keeps_input_sections()
+ {
+ gold_assert(this->input_count_ == 0);
+ Output_merge_base::do_set_keeps_input_sections();
+ }
+
private:
// We build a hash table of the fixed-size constants. Each constant
// is stored as a pointer into the section data we are accumulating.
{
public:
Output_merge_string(uint64_t addralign)
- : Output_merge_base(sizeof(Char_type), addralign), stringpool_(),
- merged_strings_(), input_count_(0)
+ : Output_merge_base(sizeof(Char_type), addralign), stringpool_(addralign),
+ merged_strings_lists_(), input_count_(0), input_size_(0)
{
- gold_assert(addralign <= sizeof(Char_type));
this->stringpool_.set_no_zero_null();
}
do_is_string()
{ return true; }
+ // Set keeps-input-sections flag.
+ void
+ do_set_keeps_input_sections()
+ {
+ gold_assert(this->input_count_ == 0);
+ Output_merge_base::do_set_keeps_input_sections();
+ }
+
private:
// The name of the string type, for stats.
const char*
// index and offset to strings.
struct Merged_string
{
- // The input object where the string was found.
- Relobj* object;
- // The input section in the input object.
- unsigned int shndx;
// The offset in the input section.
section_offset_type offset;
- // The string itself, a pointer into a Stringpool.
- const Char_type* string;
- // The length of the string in bytes, including the null terminator.
- size_t length;
// The key in the Stringpool.
Stringpool::Key stringpool_key;
- Merged_string(Relobj *objecta, unsigned int shndxa,
- section_offset_type offseta, const Char_type* stringa,
- size_t lengtha, Stringpool::Key stringpool_keya)
- : object(objecta), shndx(shndxa), offset(offseta), string(stringa),
- length(lengtha), stringpool_key(stringpool_keya)
+ Merged_string(section_offset_type offseta, Stringpool::Key stringpool_keya)
+ : offset(offseta), stringpool_key(stringpool_keya)
{ }
};
typedef std::vector<Merged_string> Merged_strings;
+ struct Merged_strings_list
+ {
+ // The input object where the strings were found.
+ Relobj* object;
+ // The input section in the input object.
+ unsigned int shndx;
+ // The list of merged strings.
+ Merged_strings merged_strings;
+
+ Merged_strings_list(Relobj* objecta, unsigned int shndxa)
+ : object(objecta), shndx(shndxa), merged_strings()
+ { }
+ };
+
+ typedef std::vector<Merged_strings_list*> Merged_strings_lists;
+
// As we see the strings, we add them to a Stringpool.
Stringpool_template<Char_type> stringpool_;
// Map from a location in an input object to an entry in the
// Stringpool.
- Merged_strings merged_strings_;
+ Merged_strings_lists merged_strings_lists_;
// The number of entries seen in input files.
size_t input_count_;
+ // The total size of input sections.
+ size_t input_size_;
};
} // End namespace gold.