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- /* A type-safe hash set.
- Copyright (C) 2014-2020 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
-
- /* Class hash_set is a hash-value based container for objects of
- KeyId type.
- KeyId may be a non-trivial (non-POD) type provided a suitabe Traits
- class. Default Traits specializations are provided for basic types
- such as integers, pointers, and std::pair. Inserted elements are
- value-initialized either to zero for POD types or by invoking their
- default ctor. Removed elements are destroyed by invoking their dtor.
- On hash_set destruction all elements are removed. Objects of
- hash_set type are copy-constructible but not assignable. */
-
- template<typename KeyId, bool Lazy = false,
- typename Traits = default_hash_traits<KeyId> >
- class hash_set
- {
- public:
- typedef typename Traits::value_type Key;
- explicit hash_set (size_t n = 13, bool ggc = false CXX_MEM_STAT_INFO)
- : m_table (n, ggc, true, GATHER_STATISTICS, 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)
- new (e) Key (k);
-
- return existed;
- }
-
- /* if the passed in key is in the map return its value otherwise NULL. */
-
- bool contains (const Key &k)
- {
- if (Lazy)
- return (m_table.find_slot_with_hash (k, Traits::hash (k), NO_INSERT)
- != NULL);
- 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 typename Traits::value_type &, Arg)>
- void traverse (Arg a) const
- {
- for (typename hash_table<Traits, Lazy>::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 (); }
-
- /* Clear the hash table. */
-
- void empty () { m_table.empty (); }
-
- /* Return true when there are no elements in this hash set. */
- bool is_empty () const { return m_table.is_empty (); }
-
- class iterator
- {
- public:
- explicit iterator (const typename hash_table<Traits,
- Lazy>::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, Lazy>::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, false, U> *);
- template<typename T, typename U>
- friend void gt_pch_nx (hash_set<T, false, U> *);
- template<typename T, typename U>
- friend void gt_pch_nx (hash_set<T, false, U> *, gt_pointer_operator, void *);
-
- hash_table<Traits, Lazy> m_table;
- };
-
- /* Generic hash_set<TYPE> debug helper.
-
- This needs to be instantiated for each hash_set<TYPE> used throughout
- the compiler like this:
-
- DEFINE_DEBUG_HASH_SET (TYPE)
-
- The reason we have a debug_helper() is because GDB can't
- disambiguate a plain call to debug(some_hash), and it must be called
- like debug<TYPE>(some_hash). */
- template<typename T>
- void
- debug_helper (hash_set<T> &ref)
- {
- for (typename hash_set<T>::iterator it = ref.begin ();
- it != ref.end (); ++it)
- {
- debug_slim (*it);
- fputc ('\n', stderr);
- }
- }
-
- #define DEFINE_DEBUG_HASH_SET(T) \
- template void debug_helper (hash_set<T> &); \
- DEBUG_FUNCTION void \
- debug (hash_set<T> &ref) \
- { \
- debug_helper <T> (ref); \
- } \
- DEBUG_FUNCTION void \
- debug (hash_set<T> *ptr) \
- { \
- if (ptr) \
- debug (*ptr); \
- else \
- fprintf (stderr, "<nil>\n"); \
- }
-
- /* ggc marking routines. */
-
- template<typename K, typename H>
- static inline void
- gt_ggc_mx (hash_set<K, false, H> *h)
- {
- gt_ggc_mx (&h->m_table);
- }
-
- template<typename K, typename H>
- static inline void
- gt_pch_nx (hash_set<K, false, H> *h)
- {
- gt_pch_nx (&h->m_table);
- }
-
- template<typename K, typename H>
- static inline void
- gt_pch_nx (hash_set<K, false, H> *h, gt_pointer_operator op, void *cookie)
- {
- op (&h->m_table.m_entries, cookie);
- }
-
- #endif
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