gcc/gcc/hash-set.h
Martin Liska ce7bc090cd hash_set: add iterator and remove method.
* hash-set.h (remove): New function.
	(iterator): New iteration class for hash_set.

From-SVN: r225885
2015-07-16 14:11:52 +00:00

149 lines
3.5 KiB
C++

/* A type-safe hash set.
Copyright (C) 2014-2015 Free Software Foundation, Inc.
This file is part of GCC.
GCC 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, or (at your option) any later
version.
GCC 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 GCC; see the file COPYING3. If not see
<http://www.gnu.org/licenses/>. */
#ifndef hash_set_h
#define hash_set_h
template<typename Key, typename Traits = default_hash_traits<Key> >
class hash_set
{
public:
explicit hash_set (size_t n = 13, bool ggc = false CXX_MEM_STAT_INFO)
: m_table (n, ggc, true, HASH_SET_ORIGIN PASS_MEM_STAT) {}
/* Create a hash_set in gc memory with space for at least n elements. */
static hash_set *
create_ggc (size_t n)
{
hash_set *set = ggc_alloc<hash_set> ();
new (set) hash_set (n, true);
return set;
}
/* If key k isn't already in the map add it to the map, and
return false. Otherwise return true. */
bool add (const Key &k)
{
Key *e = m_table.find_slot_with_hash (k, Traits::hash (k), INSERT);
bool existed = !Traits::is_empty (*e);
if (!existed)
*e = k;
return existed;
}
/* if the passed in key is in the map return its value otherwise NULL. */
bool contains (const Key &k)
{
Key &e = m_table.find_with_hash (k, Traits::hash (k));
return !Traits::is_empty (e);
}
void remove (const Key &k)
{
m_table.remove_elt_with_hash (k, Traits::hash (k));
}
/* Call the call back on each pair of key and value with the passed in
arg. */
template<typename Arg, bool (*f)(const Key &, Arg)>
void traverse (Arg a) const
{
for (typename hash_table<Traits>::iterator iter = m_table.begin ();
iter != m_table.end (); ++iter)
f (*iter, a);
}
/* Return the number of elements in the set. */
size_t elements () const { return m_table.elements (); }
class iterator
{
public:
explicit iterator (const typename hash_table<Traits>::iterator &iter) :
m_iter (iter) {}
iterator &operator++ ()
{
++m_iter;
return *this;
}
Key
operator* ()
{
return *m_iter;
}
bool
operator != (const iterator &other) const
{
return m_iter != other.m_iter;
}
private:
typename hash_table<Traits>::iterator m_iter;
};
/* Standard iterator retrieval methods. */
iterator begin () const { return iterator (m_table.begin ()); }
iterator end () const { return iterator (m_table.end ()); }
private:
template<typename T, typename U> friend void gt_ggc_mx (hash_set<T, U> *);
template<typename T, typename U> friend void gt_pch_nx (hash_set<T, U> *);
template<typename T, typename U> friend void gt_pch_nx (hash_set<T, U> *, gt_pointer_operator, void *);
hash_table<Traits> m_table;
};
/* ggc marking routines. */
template<typename K, typename H>
static inline void
gt_ggc_mx (hash_set<K, H> *h)
{
gt_ggc_mx (&h->m_table);
}
template<typename K, typename H>
static inline void
gt_pch_nx (hash_set<K, H> *h)
{
gt_pch_nx (&h->m_table);
}
template<typename K, typename H>
static inline void
gt_pch_nx (hash_set<K, H> *h, gt_pointer_operator op, void *cookie)
{
op (&h->m_table.m_entries, cookie);
}
#endif