// gc.cc -- garbage collection of unused sections
// Copyright (C) 2009-2024 Free Software Foundation, Inc.
// Written by Sriraman Tallam <
[email protected]>.
// 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.
#include "gold.h"
#include "object.h"
#include "gc.h"
#include "symtab.h"
namespace gold
{
// Garbage collection uses a worklist style algorithm to determine the
// transitive closure of all referenced sections.
void
Garbage_collection::do_transitive_closure()
{
while (!this->worklist().empty())
{
// Add elements from the work list to the referenced list
// one by one.
Section_id entry = this->worklist().back();
this->worklist().pop_back();
if (!this->referenced_list().insert(entry).second)
continue;
Garbage_collection::Section_ref::iterator find_it =
this->section_reloc_map().find(entry);
if (find_it == this->section_reloc_map().end())
continue;
const Garbage_collection::Sections_reachable &v = find_it->second;
// Scan the vector of references for each work_list entry.
for (Garbage_collection::Sections_reachable::const_iterator it_v =
v.begin();
it_v != v.end();
++it_v)
{
// Do not add already processed sections to the work_list.
if (this->referenced_list().find(*it_v)
== this->referenced_list().end())
{
this->worklist().push_back(*it_v);
}
}
}
this->worklist_ready();
}
} // End namespace gold.
