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Diffstat (limited to 'gold/icf.h')
-rw-r--r-- | gold/icf.h | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/gold/icf.h b/gold/icf.h new file mode 100644 index 0000000..965964d --- /dev/null +++ b/gold/icf.h @@ -0,0 +1,140 @@ +// icf.h -- Identical Code Folding + +// Copyright 2009 Free Software Foundation, Inc. +// Written by Sriraman Tallam <tmsriram@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_ICF_H +#define GOLD_ICF_H + +#include <vector> + +#include "elfcpp.h" +#include "symtab.h" + +namespace gold +{ + +class Object; +class Input_objects; +class Symbol_table; + +typedef std::pair<Object*, unsigned int> Section_id; + +class Icf +{ + public: + struct Section_id_hash + { + size_t operator()(const Section_id& loc) const + { return reinterpret_cast<uintptr_t>(loc.first) ^ loc.second; } + }; + + typedef std::vector<Section_id> Sections_reachable_list; + typedef std::vector<Symbol*> Symbol_info; + typedef std::vector<std::pair<long long, long long> > Addend_info; + typedef Unordered_map<Section_id, + Sections_reachable_list, + Section_id_hash> Section_list; + typedef Unordered_map<Section_id, Symbol_info, Section_id_hash> Symbol_list; + typedef Unordered_map<Section_id, Addend_info, Section_id_hash> Addend_list; + typedef Unordered_map<Section_id, + unsigned int, + Section_id_hash> Uniq_secn_id_map; + + Icf() + : id_section_(), section_id_(), kept_section_id_(), + num_tracked_relocs(NULL), icf_ready_(false), + section_reloc_list_(), symbol_reloc_list_(), + addend_reloc_list_() + { } + + // Returns the kept folded identical section corresponding to + // dup_obj and dup_shndx. + Section_id + get_folded_section(Object* dup_obj, unsigned int dup_shndx); + + // Forms groups of identical sections where the first member + // of each group is the kept section during folding. + void + find_identical_sections(const Input_objects* input_objects, + Symbol_table* symtab); + + // This is set when ICF has been run and the groups of + // identical sections have been formed. + void + icf_ready() + { this->icf_ready_ = true; } + + // Returns true if ICF has been run. + bool + is_icf_ready() + { return this->icf_ready_; } + + // Returns the kept section corresponding to the + // given section. + bool + is_section_folded(Object* obj, unsigned int shndx); + + // Returns a map of a section to a list of all sections referenced + // by its relocations. + Section_list& + section_reloc_list() + { return this->section_reloc_list_; } + + // Returns a map of a section to a list of all symbols referenced + // by its relocations. + Symbol_list& + symbol_reloc_list() + { return this->symbol_reloc_list_; } + + // Returns a maps of a section to a list of symbol values and addends + // of its relocations. + Addend_list& + addend_reloc_list() + { return this->addend_reloc_list_; } + + // Returns a mapping of each section to a unique integer. + Uniq_secn_id_map& + section_to_int_map() + { return this->section_id_; } + + private: + + // Maps integers to sections. + std::vector<Section_id> id_section_; + // Does the reverse. + Uniq_secn_id_map section_id_; + // Given a section id, this maps it to the id of the kept + // section. If the id's are the same then this section is + // not folded. + std::vector<unsigned int> kept_section_id_; + unsigned int* num_tracked_relocs; + // Flag to indicate if ICF has been run. + bool icf_ready_; + + // These lists are populated by gc_process_relocs in gc.h. + Section_list section_reloc_list_; + Symbol_list symbol_reloc_list_; + Addend_list addend_reloc_list_; +}; + +} // End of namespace gold. + +#endif |