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- /* A type-safe hash table template.
- Copyright (C) 2012-2015 Free Software Foundation, Inc.
- Contributed by Lawrence Crowl <crowl@google.com>
- 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/>. */
- /* This file implements a typed hash table.
- The implementation borrows from libiberty's htab_t in hashtab.h.
- INTRODUCTION TO TYPES
- Users of the hash table generally need to be aware of three types.
- 1. The type being placed into the hash table. This type is called
- the value type.
- 2. The type used to describe how to handle the value type within
- the hash table. This descriptor type provides the hash table with
- several things.
- - A typedef named 'value_type' to the value type (from above).
- - A static member function named 'hash' that takes a value_type
- pointer and returns a hashval_t value.
- - A typedef named 'compare_type' that is used to test when an value
- is found. This type is the comparison type. Usually, it will be the
- same as value_type. If it is not the same type, you must generally
- explicitly compute hash values and pass them to the hash table.
- - A static member function named 'equal' that takes a value_type
- pointer and a compare_type pointer, and returns a bool.
- - A static function named 'remove' that takes an value_type pointer
- and frees the memory allocated by it. This function is used when
- individual elements of the table need to be disposed of (e.g.,
- when deleting a hash table, removing elements from the table, etc).
- 3. The type of the hash table itself. (More later.)
- In very special circumstances, users may need to know about a fourth type.
- 4. The template type used to describe how hash table memory
- is allocated. This type is called the allocator type. It is
- parameterized on the value type. It provides four functions.
- - A static member function named 'data_alloc'. This function
- allocates the data elements in the table.
- - A static member function named 'data_free'. This function
- deallocates the data elements in the table.
- Hash table are instantiated with two type arguments.
- * The descriptor type, (2) above.
- * The allocator type, (4) above. In general, you will not need to
- provide your own allocator type. By default, hash tables will use
- the class template xcallocator, which uses malloc/free for allocation.
- DEFINING A DESCRIPTOR TYPE
- The first task in using the hash table is to describe the element type.
- We compose this into a few steps.
- 1. Decide on a removal policy for values stored in the table.
- This header provides class templates for the two most common
- policies.
- * typed_free_remove implements the static 'remove' member function
- by calling free().
- * typed_noop_remove implements the static 'remove' member function
- by doing nothing.
- You can use these policies by simply deriving the descriptor type
- from one of those class template, with the appropriate argument.
- Otherwise, you need to write the static 'remove' member function
- in the descriptor class.
- 2. Choose a hash function. Write the static 'hash' member function.
- 3. Choose an equality testing function. In most cases, its two
- arguments will be value_type pointers. If not, the first argument must
- be a value_type pointer, and the second argument a compare_type pointer.
- AN EXAMPLE DESCRIPTOR TYPE
- Suppose you want to put some_type into the hash table. You could define
- the descriptor type as follows.
- struct some_type_hasher : typed_noop_remove <some_type>
- // Deriving from typed_noop_remove means that we get a 'remove' that does
- // nothing. This choice is good for raw values.
- {
- typedef some_type value_type;
- typedef some_type compare_type;
- static inline hashval_t hash (const value_type *);
- static inline bool equal (const value_type *, const compare_type *);
- };
- inline hashval_t
- some_type_hasher::hash (const value_type *e)
- { ... compute and return a hash value for E ... }
- inline bool
- some_type_hasher::equal (const value_type *p1, const compare_type *p2)
- { ... compare P1 vs P2. Return true if they are the 'same' ... }
- AN EXAMPLE HASH_TABLE DECLARATION
- To instantiate a hash table for some_type:
- hash_table <some_type_hasher> some_type_hash_table;
- There is no need to mention some_type directly, as the hash table will
- obtain it using some_type_hasher::value_type.
- You can then used any of the functions in hash_table's public interface.
- See hash_table for details. The interface is very similar to libiberty's
- htab_t.
- EASY DESCRIPTORS FOR POINTERS
- The class template pointer_hash provides everything you need to hash
- pointers (as opposed to what they point to). So, to instantiate a hash
- table over pointers to whatever_type,
- hash_table <pointer_hash <whatever_type>> whatever_type_hash_table;
- HASH TABLE ITERATORS
- The hash table provides standard C++ iterators. For example, consider a
- hash table of some_info. We wish to consume each element of the table:
- extern void consume (some_info *);
- We define a convenience typedef and the hash table:
- typedef hash_table <some_info_hasher> info_table_type;
- info_table_type info_table;
- Then we write the loop in typical C++ style:
- for (info_table_type::iterator iter = info_table.begin ();
- iter != info_table.end ();
- ++iter)
- if ((*iter).status == INFO_READY)
- consume (&*iter);
- Or with common sub-expression elimination:
- for (info_table_type::iterator iter = info_table.begin ();
- iter != info_table.end ();
- ++iter)
- {
- some_info &elem = *iter;
- if (elem.status == INFO_READY)
- consume (&elem);
- }
- One can also use a more typical GCC style:
- typedef some_info *some_info_p;
- some_info *elem_ptr;
- info_table_type::iterator iter;
- FOR_EACH_HASH_TABLE_ELEMENT (info_table, elem_ptr, some_info_p, iter)
- if (elem_ptr->status == INFO_READY)
- consume (elem_ptr);
- */
- #ifndef TYPED_HASHTAB_H
- #define TYPED_HASHTAB_H
- #include "ggc.h"
- #include "hashtab.h"
- #include <new>
- template<typename, typename, typename> class hash_map;
- template<typename, typename> class hash_set;
- /* The ordinary memory allocator. */
- /* FIXME (crowl): This allocator may be extracted for wider sharing later. */
- template <typename Type>
- struct xcallocator
- {
- static Type *data_alloc (size_t count);
- static void data_free (Type *memory);
- };
- /* Allocate memory for COUNT data blocks. */
- template <typename Type>
- inline Type *
- xcallocator <Type>::data_alloc (size_t count)
- {
- return static_cast <Type *> (xcalloc (count, sizeof (Type)));
- }
- /* Free memory for data blocks. */
- template <typename Type>
- inline void
- xcallocator <Type>::data_free (Type *memory)
- {
- return ::free (memory);
- }
- /* Helpful type for removing with free. */
- template <typename Type>
- struct typed_free_remove
- {
- static inline void remove (Type *p);
- };
- /* Remove with free. */
- template <typename Type>
- inline void
- typed_free_remove <Type>::remove (Type *p)
- {
- free (p);
- }
- /* Helpful type for a no-op remove. */
- template <typename Type>
- struct typed_noop_remove
- {
- static inline void remove (Type *p);
- };
- /* Remove doing nothing. */
- template <typename Type>
- inline void
- typed_noop_remove <Type>::remove (Type *p ATTRIBUTE_UNUSED)
- {
- }
- /* Pointer hash with a no-op remove method. */
- template <typename Type>
- struct pointer_hash : typed_noop_remove <Type>
- {
- typedef Type *value_type;
- typedef Type *compare_type;
- typedef int store_values_directly;
- static inline hashval_t hash (const value_type &);
- static inline bool equal (const value_type &existing,
- const compare_type &candidate);
- };
- template <typename Type>
- inline hashval_t
- pointer_hash <Type>::hash (const value_type &candidate)
- {
- /* This is a really poor hash function, but it is what the current code uses,
- so I am reusing it to avoid an additional axis in testing. */
- return (hashval_t) ((intptr_t)candidate >> 3);
- }
- template <typename Type>
- inline bool
- pointer_hash <Type>::equal (const value_type &existing,
- const compare_type &candidate)
- {
- return existing == candidate;
- }
- /* Hasher for entry in gc memory. */
- template<typename T>
- struct ggc_hasher
- {
- typedef T value_type;
- typedef T compare_type;
- typedef int store_values_directly;
- static void remove (T) {}
- static void
- ggc_mx (T p)
- {
- extern void gt_ggc_mx (T &);
- gt_ggc_mx (p);
- }
- static void
- pch_nx (T &p)
- {
- extern void gt_pch_nx (T &);
- gt_pch_nx (p);
- }
- static void
- pch_nx (T &p, gt_pointer_operator op, void *cookie)
- {
- op (&p, cookie);
- }
- };
- /* Hasher for cache entry in gc memory. */
- template<typename T>
- struct ggc_cache_hasher
- {
- typedef T value_type;
- typedef T compare_type;
- typedef int store_values_directly;
- static void remove (T &) {}
- /* Entries are weakly held because this is for caches. */
- static void ggc_mx (T &) {}
- static void
- pch_nx (T &p)
- {
- extern void gt_pch_nx (T &);
- gt_pch_nx (p);
- }
- static void
- pch_nx (T &p, gt_pointer_operator op, void *cookie)
- {
- op (&p, cookie);
- }
- /* Clear out entries if they are about to be gc'd. */
- static void
- handle_cache_entry (T &e)
- {
- if (e != HTAB_EMPTY_ENTRY && e != HTAB_DELETED_ENTRY && !ggc_marked_p (e))
- e = static_cast<T> (HTAB_DELETED_ENTRY);
- }
- };
- /* Table of primes and their inversion information. */
- struct prime_ent
- {
- hashval_t prime;
- hashval_t inv;
- hashval_t inv_m2; /* inverse of prime-2 */
- hashval_t shift;
- };
- extern struct prime_ent const prime_tab[];
- /* Functions for computing hash table indexes. */
- extern unsigned int hash_table_higher_prime_index (unsigned long n)
- ATTRIBUTE_PURE;
- /* Return X % Y using multiplicative inverse values INV and SHIFT.
- The multiplicative inverses computed above are for 32-bit types,
- and requires that we be able to compute a highpart multiply.
- FIX: I am not at all convinced that
- 3 loads, 2 multiplications, 3 shifts, and 3 additions
- will be faster than
- 1 load and 1 modulus
- on modern systems running a compiler. */
- inline hashval_t
- mul_mod (hashval_t x, hashval_t y, hashval_t inv, int shift)
- {
- hashval_t t1, t2, t3, t4, q, r;
- t1 = ((uint64_t)x * inv) >> 32;
- t2 = x - t1;
- t3 = t2 >> 1;
- t4 = t1 + t3;
- q = t4 >> shift;
- r = x - (q * y);
- return r;
- }
- /* Compute the primary table index for HASH given current prime index. */
- inline hashval_t
- hash_table_mod1 (hashval_t hash, unsigned int index)
- {
- const struct prime_ent *p = &prime_tab[index];
- gcc_checking_assert (sizeof (hashval_t) * CHAR_BIT <= 32);
- return mul_mod (hash, p->prime, p->inv, p->shift);
- }
- /* Compute the secondary table index for HASH given current prime index. */
- inline hashval_t
- hash_table_mod2 (hashval_t hash, unsigned int index)
- {
- const struct prime_ent *p = &prime_tab[index];
- gcc_checking_assert (sizeof (hashval_t) * CHAR_BIT <= 32);
- return 1 + mul_mod (hash, p->prime - 2, p->inv_m2, p->shift);
- }
- /* The below is some template meta programming to decide if we should use the
- hash table partial specialization that directly stores value_type instead of
- pointers to value_type. If the Descriptor type defines the type
- Descriptor::store_values_directly then values are stored directly otherwise
- pointers to them are stored. */
- template<typename T> struct notype { typedef void type; };
- template<typename T, typename = void>
- struct storage_tester
- {
- static const bool value = false;
- };
- template<typename T>
- struct storage_tester<T, typename notype<typename
- T::store_values_directly>::type>
- {
- static const bool value = true;
- };
- template<typename Traits>
- struct has_is_deleted
- {
- template<typename U, bool (*)(U &)> struct helper {};
- template<typename U> static char test (helper<U, U::is_deleted> *);
- template<typename U> static int test (...);
- static const bool value = sizeof (test<Traits> (0)) == sizeof (char);
- };
- template<typename Type, typename Traits, bool = has_is_deleted<Traits>::value>
- struct is_deleted_helper
- {
- static inline bool
- call (Type &v)
- {
- return Traits::is_deleted (v);
- }
- };
- template<typename Type, typename Traits>
- struct is_deleted_helper<Type *, Traits, false>
- {
- static inline bool
- call (Type *v)
- {
- return v == HTAB_DELETED_ENTRY;
- }
- };
- template<typename Traits>
- struct has_is_empty
- {
- template<typename U, bool (*)(U &)> struct helper {};
- template<typename U> static char test (helper<U, U::is_empty> *);
- template<typename U> static int test (...);
- static const bool value = sizeof (test<Traits> (0)) == sizeof (char);
- };
- template<typename Type, typename Traits, bool = has_is_deleted<Traits>::value>
- struct is_empty_helper
- {
- static inline bool
- call (Type &v)
- {
- return Traits::is_empty (v);
- }
- };
- template<typename Type, typename Traits>
- struct is_empty_helper<Type *, Traits, false>
- {
- static inline bool
- call (Type *v)
- {
- return v == HTAB_EMPTY_ENTRY;
- }
- };
- template<typename Traits>
- struct has_mark_deleted
- {
- template<typename U, void (*)(U &)> struct helper {};
- template<typename U> static char test (helper<U, U::mark_deleted> *);
- template<typename U> static int test (...);
- static const bool value = sizeof (test<Traits> (0)) == sizeof (char);
- };
- template<typename Type, typename Traits, bool = has_is_deleted<Traits>::value>
- struct mark_deleted_helper
- {
- static inline void
- call (Type &v)
- {
- Traits::mark_deleted (v);
- }
- };
- template<typename Type, typename Traits>
- struct mark_deleted_helper<Type *, Traits, false>
- {
- static inline void
- call (Type *&v)
- {
- v = static_cast<Type *> (HTAB_DELETED_ENTRY);
- }
- };
- template<typename Traits>
- struct has_mark_empty
- {
- template<typename U, void (*)(U &)> struct helper {};
- template<typename U> static char test (helper<U, U::mark_empty> *);
- template<typename U> static int test (...);
- static const bool value = sizeof (test<Traits> (0)) == sizeof (char);
- };
- template<typename Type, typename Traits, bool = has_is_deleted<Traits>::value>
- struct mark_empty_helper
- {
- static inline void
- call (Type &v)
- {
- Traits::mark_empty (v);
- }
- };
- template<typename Type, typename Traits>
- struct mark_empty_helper<Type *, Traits, false>
- {
- static inline void
- call (Type *&v)
- {
- v = static_cast<Type *> (HTAB_EMPTY_ENTRY);
- }
- };
- /* User-facing hash table type.
- The table stores elements of type Descriptor::value_type, or pointers to
- objects of type value_type if the descriptor does not define the type
- store_values_directly.
- It hashes values with the hash member function.
- The table currently works with relatively weak hash functions.
- Use typed_pointer_hash <Value> when hashing pointers instead of objects.
- It compares elements with the equal member function.
- Two elements with the same hash may not be equal.
- Use typed_pointer_equal <Value> when hashing pointers instead of objects.
- It removes elements with the remove member function.
- This feature is useful for freeing memory.
- Derive from typed_null_remove <Value> when not freeing objects.
- Derive from typed_free_remove <Value> when doing a simple object free.
- Specify the template Allocator to allocate and free memory.
- The default is xcallocator.
- Storage is an implementation detail and should not be used outside the
- hash table code.
- */
- template <typename Descriptor,
- template<typename Type> class Allocator= xcallocator,
- bool Storage = storage_tester<Descriptor>::value>
- class hash_table
- {
- };
- template <typename Descriptor,
- template<typename Type> class Allocator>
- class hash_table<Descriptor, Allocator, false>
- {
- typedef typename Descriptor::value_type value_type;
- typedef typename Descriptor::compare_type compare_type;
- public:
- hash_table (size_t);
- ~hash_table ();
- /* Current size (in entries) of the hash table. */
- size_t size () const { return m_size; }
- /* Return the current number of elements in this hash table. */
- size_t elements () const { return m_n_elements - m_n_deleted; }
- /* Return the current number of elements in this hash table. */
- size_t elements_with_deleted () const { return m_n_elements; }
- /* This function clears all entries in the given hash table. */
- void empty ();
- /* This function clears a specified SLOT in a hash table. It is
- useful when you've already done the lookup and don't want to do it
- again. */
- void clear_slot (value_type **);
- /* This function searches for a hash table entry equal to the given
- COMPARABLE element starting with the given HASH value. It cannot
- be used to insert or delete an element. */
- value_type *find_with_hash (const compare_type *, hashval_t);
- /* Like find_slot_with_hash, but compute the hash value from the element. */
- value_type *find (const value_type *value)
- {
- return find_with_hash (value, Descriptor::hash (value));
- }
- value_type **find_slot (const value_type *value, insert_option insert)
- {
- return find_slot_with_hash (value, Descriptor::hash (value), insert);
- }
- /* This function searches for a hash table slot containing an entry
- equal to the given COMPARABLE element and starting with the given
- HASH. To delete an entry, call this with insert=NO_INSERT, then
- call clear_slot on the slot returned (possibly after doing some
- checks). To insert an entry, call this with insert=INSERT, then
- write the value you want into the returned slot. When inserting an
- entry, NULL may be returned if memory allocation fails. */
- value_type **find_slot_with_hash (const compare_type *comparable,
- hashval_t hash, enum insert_option insert);
- /* This function deletes an element with the given COMPARABLE value
- from hash table starting with the given HASH. If there is no
- matching element in the hash table, this function does nothing. */
- void remove_elt_with_hash (const compare_type *, hashval_t);
- /* Like remove_elt_with_hash, but compute the hash value from the element. */
- void remove_elt (const value_type *value)
- {
- remove_elt_with_hash (value, Descriptor::hash (value));
- }
- /* This function scans over the entire hash table calling CALLBACK for
- each live entry. If CALLBACK returns false, the iteration stops.
- ARGUMENT is passed as CALLBACK's second argument. */
- template <typename Argument,
- int (*Callback) (value_type **slot, Argument argument)>
- void traverse_noresize (Argument argument);
- /* Like traverse_noresize, but does resize the table when it is too empty
- to improve effectivity of subsequent calls. */
- template <typename Argument,
- int (*Callback) (value_type **slot, Argument argument)>
- void traverse (Argument argument);
- class iterator
- {
- public:
- iterator () : m_slot (NULL), m_limit (NULL) {}
- iterator (value_type **slot, value_type **limit) :
- m_slot (slot), m_limit (limit) {}
- inline value_type *operator * () { return *m_slot; }
- void slide ();
- inline iterator &operator ++ ();
- bool operator != (const iterator &other) const
- {
- return m_slot != other.m_slot || m_limit != other.m_limit;
- }
- private:
- value_type **m_slot;
- value_type **m_limit;
- };
- iterator begin () const
- {
- iterator iter (m_entries, m_entries + m_size);
- iter.slide ();
- return iter;
- }
- iterator end () const { return iterator (); }
- double collisions () const
- {
- return m_searches ? static_cast <double> (m_collisions) / m_searches : 0;
- }
- private:
- value_type **find_empty_slot_for_expand (hashval_t);
- void expand ();
- /* Table itself. */
- typename Descriptor::value_type **m_entries;
- size_t m_size;
- /* Current number of elements including also deleted elements. */
- size_t m_n_elements;
- /* Current number of deleted elements in the table. */
- size_t m_n_deleted;
- /* The following member is used for debugging. Its value is number
- of all calls of `htab_find_slot' for the hash table. */
- unsigned int m_searches;
- /* The following member is used for debugging. Its value is number
- of collisions fixed for time of work with the hash table. */
- unsigned int m_collisions;
- /* Current size (in entries) of the hash table, as an index into the
- table of primes. */
- unsigned int m_size_prime_index;
- };
- template<typename Descriptor, template<typename Type> class Allocator>
- hash_table<Descriptor, Allocator, false>::hash_table (size_t size) :
- m_n_elements (0), m_n_deleted (0), m_searches (0), m_collisions (0)
- {
- unsigned int size_prime_index;
- size_prime_index = hash_table_higher_prime_index (size);
- size = prime_tab[size_prime_index].prime;
- m_entries = Allocator <value_type*> ::data_alloc (size);
- gcc_assert (m_entries != NULL);
- m_size = size;
- m_size_prime_index = size_prime_index;
- }
- template<typename Descriptor, template<typename Type> class Allocator>
- hash_table<Descriptor, Allocator, false>::~hash_table ()
- {
- for (size_t i = m_size - 1; i < m_size; i--)
- if (m_entries[i] != HTAB_EMPTY_ENTRY && m_entries[i] != HTAB_DELETED_ENTRY)
- Descriptor::remove (m_entries[i]);
- Allocator <value_type *> ::data_free (m_entries);
- }
- /* Similar to find_slot, but without several unwanted side effects:
- - Does not call equal when it finds an existing entry.
- - Does not change the count of elements/searches/collisions in the
- hash table.
- This function also assumes there are no deleted entries in the table.
- HASH is the hash value for the element to be inserted. */
- template<typename Descriptor, template<typename Type> class Allocator>
- typename hash_table<Descriptor, Allocator, false>::value_type **
- hash_table<Descriptor, Allocator, false>
- ::find_empty_slot_for_expand (hashval_t hash)
- {
- hashval_t index = hash_table_mod1 (hash, m_size_prime_index);
- size_t size = m_size;
- value_type **slot = m_entries + index;
- hashval_t hash2;
- if (*slot == HTAB_EMPTY_ENTRY)
- return slot;
- gcc_checking_assert (*slot != HTAB_DELETED_ENTRY);
- hash2 = hash_table_mod2 (hash, m_size_prime_index);
- for (;;)
- {
- index += hash2;
- if (index >= size)
- index -= size;
- slot = m_entries + index;
- if (*slot == HTAB_EMPTY_ENTRY)
- return slot;
- gcc_checking_assert (*slot != HTAB_DELETED_ENTRY);
- }
- }
- /* The following function changes size of memory allocated for the
- entries and repeatedly inserts the table elements. The occupancy
- of the table after the call will be about 50%. Naturally the hash
- table must already exist. Remember also that the place of the
- table entries is changed. If memory allocation fails, this function
- will abort. */
- template<typename Descriptor, template<typename Type> class Allocator>
- void
- hash_table<Descriptor, Allocator, false>::expand ()
- {
- value_type **oentries = m_entries;
- unsigned int oindex = m_size_prime_index;
- size_t osize = size ();
- value_type **olimit = oentries + osize;
- size_t elts = elements ();
- /* Resize only when table after removal of unused elements is either
- too full or too empty. */
- unsigned int nindex;
- size_t nsize;
- if (elts * 2 > osize || (elts * 8 < osize && osize > 32))
- {
- nindex = hash_table_higher_prime_index (elts * 2);
- nsize = prime_tab[nindex].prime;
- }
- else
- {
- nindex = oindex;
- nsize = osize;
- }
- value_type **nentries = Allocator <value_type *> ::data_alloc (nsize);
- gcc_assert (nentries != NULL);
- m_entries = nentries;
- m_size = nsize;
- m_size_prime_index = nindex;
- m_n_elements -= m_n_deleted;
- m_n_deleted = 0;
- value_type **p = oentries;
- do
- {
- value_type *x = *p;
- if (x != HTAB_EMPTY_ENTRY && x != HTAB_DELETED_ENTRY)
- {
- value_type **q = find_empty_slot_for_expand (Descriptor::hash (x));
- *q = x;
- }
- p++;
- }
- while (p < olimit);
- Allocator <value_type *> ::data_free (oentries);
- }
- template<typename Descriptor, template<typename Type> class Allocator>
- void
- hash_table<Descriptor, Allocator, false>::empty ()
- {
- size_t size = m_size;
- value_type **entries = m_entries;
- int i;
- for (i = size - 1; i >= 0; i--)
- if (entries[i] != HTAB_EMPTY_ENTRY && entries[i] != HTAB_DELETED_ENTRY)
- Descriptor::remove (entries[i]);
- /* Instead of clearing megabyte, downsize the table. */
- if (size > 1024*1024 / sizeof (PTR))
- {
- int nindex = hash_table_higher_prime_index (1024 / sizeof (PTR));
- int nsize = prime_tab[nindex].prime;
- Allocator <value_type *> ::data_free (m_entries);
- m_entries = Allocator <value_type *> ::data_alloc (nsize);
- m_size = nsize;
- m_size_prime_index = nindex;
- }
- else
- memset (entries, 0, size * sizeof (value_type *));
- m_n_deleted = 0;
- m_n_elements = 0;
- }
- /* This function clears a specified SLOT in a hash table. It is
- useful when you've already done the lookup and don't want to do it
- again. */
- template<typename Descriptor, template<typename Type> class Allocator>
- void
- hash_table<Descriptor, Allocator, false>::clear_slot (value_type **slot)
- {
- gcc_checking_assert (!(slot < m_entries || slot >= m_entries + size ()
- || *slot == HTAB_EMPTY_ENTRY
- || *slot == HTAB_DELETED_ENTRY));
- Descriptor::remove (*slot);
- *slot = static_cast <value_type *> (HTAB_DELETED_ENTRY);
- m_n_deleted++;
- }
- /* This function searches for a hash table entry equal to the given
- COMPARABLE element starting with the given HASH value. It cannot
- be used to insert or delete an element. */
- template<typename Descriptor, template<typename Type> class Allocator>
- typename hash_table<Descriptor, Allocator, false>::value_type *
- hash_table<Descriptor, Allocator, false>
- ::find_with_hash (const compare_type *comparable, hashval_t hash)
- {
- m_searches++;
- size_t size = m_size;
- hashval_t index = hash_table_mod1 (hash, m_size_prime_index);
- value_type *entry = m_entries[index];
- if (entry == HTAB_EMPTY_ENTRY
- || (entry != HTAB_DELETED_ENTRY && Descriptor::equal (entry, comparable)))
- return entry;
- hashval_t hash2 = hash_table_mod2 (hash, m_size_prime_index);
- for (;;)
- {
- m_collisions++;
- index += hash2;
- if (index >= size)
- index -= size;
- entry = m_entries[index];
- if (entry == HTAB_EMPTY_ENTRY
- || (entry != HTAB_DELETED_ENTRY
- && Descriptor::equal (entry, comparable)))
- return entry;
- }
- }
- /* This function searches for a hash table slot containing an entry
- equal to the given COMPARABLE element and starting with the given
- HASH. To delete an entry, call this with insert=NO_INSERT, then
- call clear_slot on the slot returned (possibly after doing some
- checks). To insert an entry, call this with insert=INSERT, then
- write the value you want into the returned slot. When inserting an
- entry, NULL may be returned if memory allocation fails. */
- template<typename Descriptor, template<typename Type> class Allocator>
- typename hash_table<Descriptor, Allocator, false>::value_type **
- hash_table<Descriptor, Allocator, false>
- ::find_slot_with_hash (const compare_type *comparable, hashval_t hash,
- enum insert_option insert)
- {
- if (insert == INSERT && m_size * 3 <= m_n_elements * 4)
- expand ();
- m_searches++;
- value_type **first_deleted_slot = NULL;
- hashval_t index = hash_table_mod1 (hash, m_size_prime_index);
- hashval_t hash2 = hash_table_mod2 (hash, m_size_prime_index);
- value_type *entry = m_entries[index];
- size_t size = m_size;
- if (entry == HTAB_EMPTY_ENTRY)
- goto empty_entry;
- else if (entry == HTAB_DELETED_ENTRY)
- first_deleted_slot = &m_entries[index];
- else if (Descriptor::equal (entry, comparable))
- return &m_entries[index];
- for (;;)
- {
- m_collisions++;
- index += hash2;
- if (index >= size)
- index -= size;
- entry = m_entries[index];
- if (entry == HTAB_EMPTY_ENTRY)
- goto empty_entry;
- else if (entry == HTAB_DELETED_ENTRY)
- {
- if (!first_deleted_slot)
- first_deleted_slot = &m_entries[index];
- }
- else if (Descriptor::equal (entry, comparable))
- return &m_entries[index];
- }
- empty_entry:
- if (insert == NO_INSERT)
- return NULL;
- if (first_deleted_slot)
- {
- m_n_deleted--;
- *first_deleted_slot = static_cast <value_type *> (HTAB_EMPTY_ENTRY);
- return first_deleted_slot;
- }
- m_n_elements++;
- return &m_entries[index];
- }
- /* This function deletes an element with the given COMPARABLE value
- from hash table starting with the given HASH. If there is no
- matching element in the hash table, this function does nothing. */
- template<typename Descriptor, template<typename Type> class Allocator>
- void
- hash_table<Descriptor, Allocator, false>
- ::remove_elt_with_hash (const compare_type *comparable, hashval_t hash)
- {
- value_type **slot = find_slot_with_hash (comparable, hash, NO_INSERT);
- if (*slot == HTAB_EMPTY_ENTRY)
- return;
- Descriptor::remove (*slot);
- *slot = static_cast <value_type *> (HTAB_DELETED_ENTRY);
- m_n_deleted++;
- }
- /* This function scans over the entire hash table calling CALLBACK for
- each live entry. If CALLBACK returns false, the iteration stops.
- ARGUMENT is passed as CALLBACK's second argument. */
- template<typename Descriptor, template<typename Type> class Allocator>
- template<typename Argument,
- int (*Callback) (typename hash_table<Descriptor, Allocator,
- false>::value_type **slot,
- Argument argument)>
- void
- hash_table<Descriptor, Allocator, false>::traverse_noresize (Argument argument)
- {
- value_type **slot = m_entries;
- value_type **limit = slot + size ();
- do
- {
- value_type *x = *slot;
- if (x != HTAB_EMPTY_ENTRY && x != HTAB_DELETED_ENTRY)
- if (! Callback (slot, argument))
- break;
- }
- while (++slot < limit);
- }
- /* Like traverse_noresize, but does resize the table when it is too empty
- to improve effectivity of subsequent calls. */
- template <typename Descriptor,
- template <typename Type> class Allocator>
- template <typename Argument,
- int (*Callback) (typename hash_table<Descriptor, Allocator,
- false>::value_type **slot,
- Argument argument)>
- void
- hash_table<Descriptor, Allocator, false>::traverse (Argument argument)
- {
- size_t size = m_size;
- if (elements () * 8 < size && size > 32)
- expand ();
- traverse_noresize <Argument, Callback> (argument);
- }
- /* Slide down the iterator slots until an active entry is found. */
- template<typename Descriptor, template<typename Type> class Allocator>
- void
- hash_table<Descriptor, Allocator, false>::iterator::slide ()
- {
- for ( ; m_slot < m_limit; ++m_slot )
- {
- value_type *x = *m_slot;
- if (x != HTAB_EMPTY_ENTRY && x != HTAB_DELETED_ENTRY)
- return;
- }
- m_slot = NULL;
- m_limit = NULL;
- }
- /* Bump the iterator. */
- template<typename Descriptor, template<typename Type> class Allocator>
- inline typename hash_table<Descriptor, Allocator, false>::iterator &
- hash_table<Descriptor, Allocator, false>::iterator::operator ++ ()
- {
- ++m_slot;
- slide ();
- return *this;
- }
- /* A partial specialization used when values should be stored directly. */
- template <typename Descriptor,
- template<typename Type> class Allocator>
- class hash_table<Descriptor, Allocator, true>
- {
- typedef typename Descriptor::value_type value_type;
- typedef typename Descriptor::compare_type compare_type;
- public:
- explicit hash_table (size_t, bool ggc = false);
- ~hash_table ();
- /* Create a hash_table in gc memory. */
- static hash_table *
- create_ggc (size_t n)
- {
- hash_table *table = ggc_alloc<hash_table> ();
- new (table) hash_table (n, true);
- return table;
- }
- /* Current size (in entries) of the hash table. */
- size_t size () const { return m_size; }
- /* Return the current number of elements in this hash table. */
- size_t elements () const { return m_n_elements - m_n_deleted; }
- /* Return the current number of elements in this hash table. */
- size_t elements_with_deleted () const { return m_n_elements; }
- /* This function clears all entries in the given hash table. */
- void empty ();
- /* This function clears a specified SLOT in a hash table. It is
- useful when you've already done the lookup and don't want to do it
- again. */
- void clear_slot (value_type *);
- /* This function searches for a hash table entry equal to the given
- COMPARABLE element starting with the given HASH value. It cannot
- be used to insert or delete an element. */
- value_type &find_with_hash (const compare_type &, hashval_t);
- /* Like find_slot_with_hash, but compute the hash value from the element. */
- value_type &find (const value_type &value)
- {
- return find_with_hash (value, Descriptor::hash (value));
- }
- value_type *find_slot (const value_type &value, insert_option insert)
- {
- return find_slot_with_hash (value, Descriptor::hash (value), insert);
- }
- /* This function searches for a hash table slot containing an entry
- equal to the given COMPARABLE element and starting with the given
- HASH. To delete an entry, call this with insert=NO_INSERT, then
- call clear_slot on the slot returned (possibly after doing some
- checks). To insert an entry, call this with insert=INSERT, then
- write the value you want into the returned slot. When inserting an
- entry, NULL may be returned if memory allocation fails. */
- value_type *find_slot_with_hash (const compare_type &comparable,
- hashval_t hash, enum insert_option insert);
- /* This function deletes an element with the given COMPARABLE value
- from hash table starting with the given HASH. If there is no
- matching element in the hash table, this function does nothing. */
- void remove_elt_with_hash (const compare_type &, hashval_t);
- /* Like remove_elt_with_hash, but compute the hash value from the element. */
- void remove_elt (const value_type &value)
- {
- remove_elt_with_hash (value, Descriptor::hash (value));
- }
- /* This function scans over the entire hash table calling CALLBACK for
- each live entry. If CALLBACK returns false, the iteration stops.
- ARGUMENT is passed as CALLBACK's second argument. */
- template <typename Argument,
- int (*Callback) (value_type *slot, Argument argument)>
- void traverse_noresize (Argument argument);
- /* Like traverse_noresize, but does resize the table when it is too empty
- to improve effectivity of subsequent calls. */
- template <typename Argument,
- int (*Callback) (value_type *slot, Argument argument)>
- void traverse (Argument argument);
- class iterator
- {
- public:
- iterator () : m_slot (NULL), m_limit (NULL) {}
- iterator (value_type *slot, value_type *limit) :
- m_slot (slot), m_limit (limit) {}
- inline value_type &operator * () { return *m_slot; }
- void slide ();
- inline iterator &operator ++ ();
- bool operator != (const iterator &other) const
- {
- return m_slot != other.m_slot || m_limit != other.m_limit;
- }
- private:
- value_type *m_slot;
- value_type *m_limit;
- };
- iterator begin () const
- {
- iterator iter (m_entries, m_entries + m_size);
- iter.slide ();
- return iter;
- }
- iterator end () const { return iterator (); }
- double collisions () const
- {
- return m_searches ? static_cast <double> (m_collisions) / m_searches : 0;
- }
- private:
- template<typename T> friend void gt_ggc_mx (hash_table<T> *);
- template<typename T> friend void gt_pch_nx (hash_table<T> *);
- template<typename T> friend void
- hashtab_entry_note_pointers (void *, void *, gt_pointer_operator, void *);
- template<typename T, typename U, typename V> friend void
- gt_pch_nx (hash_map<T, U, V> *, gt_pointer_operator, void *);
- template<typename T, typename U> friend void gt_pch_nx (hash_set<T, U> *,
- gt_pointer_operator,
- void *);
- template<typename T> friend void gt_pch_nx (hash_table<T> *,
- gt_pointer_operator, void *);
- value_type *alloc_entries (size_t n) const;
- value_type *find_empty_slot_for_expand (hashval_t);
- void expand ();
- static bool is_deleted (value_type &v)
- {
- return is_deleted_helper<value_type, Descriptor>::call (v);
- }
- static bool is_empty (value_type &v)
- {
- return is_empty_helper<value_type, Descriptor>::call (v);
- }
- static void mark_deleted (value_type &v)
- {
- return mark_deleted_helper<value_type, Descriptor>::call (v);
- }
- static void mark_empty (value_type &v)
- {
- return mark_empty_helper<value_type, Descriptor>::call (v);
- }
- /* Table itself. */
- typename Descriptor::value_type *m_entries;
- size_t m_size;
- /* Current number of elements including also deleted elements. */
- size_t m_n_elements;
- /* Current number of deleted elements in the table. */
- size_t m_n_deleted;
- /* The following member is used for debugging. Its value is number
- of all calls of `htab_find_slot' for the hash table. */
- unsigned int m_searches;
- /* The following member is used for debugging. Its value is number
- of collisions fixed for time of work with the hash table. */
- unsigned int m_collisions;
- /* Current size (in entries) of the hash table, as an index into the
- table of primes. */
- unsigned int m_size_prime_index;
- /* if m_entries is stored in ggc memory. */
- bool m_ggc;
- };
- template<typename Descriptor, template<typename Type> class Allocator>
- hash_table<Descriptor, Allocator, true>::hash_table (size_t size, bool ggc) :
- m_n_elements (0), m_n_deleted (0), m_searches (0), m_collisions (0),
- m_ggc (ggc)
- {
- unsigned int size_prime_index;
- size_prime_index = hash_table_higher_prime_index (size);
- size = prime_tab[size_prime_index].prime;
- m_entries = alloc_entries (size);
- m_size = size;
- m_size_prime_index = size_prime_index;
- }
- template<typename Descriptor, template<typename Type> class Allocator>
- hash_table<Descriptor, Allocator, true>::~hash_table ()
- {
- for (size_t i = m_size - 1; i < m_size; i--)
- if (!is_empty (m_entries[i]) && !is_deleted (m_entries[i]))
- Descriptor::remove (m_entries[i]);
- if (!m_ggc)
- Allocator <value_type> ::data_free (m_entries);
- else
- ggc_free (m_entries);
- }
- /* This function returns an array of empty hash table elements. */
- template<typename Descriptor, template<typename Type> class Allocator>
- inline typename hash_table<Descriptor, Allocator, true>::value_type *
- hash_table<Descriptor, Allocator, true>::alloc_entries (size_t n) const
- {
- value_type *nentries;
- if (!m_ggc)
- nentries = Allocator <value_type> ::data_alloc (n);
- else
- nentries = ::ggc_cleared_vec_alloc<value_type> (n);
- gcc_assert (nentries != NULL);
- for (size_t i = 0; i < n; i++)
- mark_empty (nentries[i]);
- return nentries;
- }
- /* Similar to find_slot, but without several unwanted side effects:
- - Does not call equal when it finds an existing entry.
- - Does not change the count of elements/searches/collisions in the
- hash table.
- This function also assumes there are no deleted entries in the table.
- HASH is the hash value for the element to be inserted. */
- template<typename Descriptor, template<typename Type> class Allocator>
- typename hash_table<Descriptor, Allocator, true>::value_type *
- hash_table<Descriptor, Allocator, true>
- ::find_empty_slot_for_expand (hashval_t hash)
- {
- hashval_t index = hash_table_mod1 (hash, m_size_prime_index);
- size_t size = m_size;
- value_type *slot = m_entries + index;
- hashval_t hash2;
- if (is_empty (*slot))
- return slot;
- #ifdef ENABLE_CHECKING
- gcc_checking_assert (!is_deleted (*slot));
- #endif
- hash2 = hash_table_mod2 (hash, m_size_prime_index);
- for (;;)
- {
- index += hash2;
- if (index >= size)
- index -= size;
- slot = m_entries + index;
- if (is_empty (*slot))
- return slot;
- #ifdef ENABLE_CHECKING
- gcc_checking_assert (!is_deleted (*slot));
- #endif
- }
- }
- /* The following function changes size of memory allocated for the
- entries and repeatedly inserts the table elements. The occupancy
- of the table after the call will be about 50%. Naturally the hash
- table must already exist. Remember also that the place of the
- table entries is changed. If memory allocation fails, this function
- will abort. */
- template<typename Descriptor, template<typename Type> class Allocator>
- void
- hash_table<Descriptor, Allocator, true>::expand ()
- {
- value_type *oentries = m_entries;
- unsigned int oindex = m_size_prime_index;
- size_t osize = size ();
- value_type *olimit = oentries + osize;
- size_t elts = elements ();
- /* Resize only when table after removal of unused elements is either
- too full or too empty. */
- unsigned int nindex;
- size_t nsize;
- if (elts * 2 > osize || (elts * 8 < osize && osize > 32))
- {
- nindex = hash_table_higher_prime_index (elts * 2);
- nsize = prime_tab[nindex].prime;
- }
- else
- {
- nindex = oindex;
- nsize = osize;
- }
- value_type *nentries = alloc_entries (nsize);
- m_entries = nentries;
- m_size = nsize;
- m_size_prime_index = nindex;
- m_n_elements -= m_n_deleted;
- m_n_deleted = 0;
- value_type *p = oentries;
- do
- {
- value_type &x = *p;
- if (!is_empty (x) && !is_deleted (x))
- {
- value_type *q = find_empty_slot_for_expand (Descriptor::hash (x));
- *q = x;
- }
- p++;
- }
- while (p < olimit);
- if (!m_ggc)
- Allocator <value_type> ::data_free (oentries);
- else
- ggc_free (oentries);
- }
- template<typename Descriptor, template<typename Type> class Allocator>
- void
- hash_table<Descriptor, Allocator, true>::empty ()
- {
- size_t size = m_size;
- value_type *entries = m_entries;
- int i;
- for (i = size - 1; i >= 0; i--)
- if (!is_empty (entries[i]) && !is_deleted (entries[i]))
- Descriptor::remove (entries[i]);
- /* Instead of clearing megabyte, downsize the table. */
- if (size > 1024*1024 / sizeof (PTR))
- {
- int nindex = hash_table_higher_prime_index (1024 / sizeof (PTR));
- int nsize = prime_tab[nindex].prime;
- if (!m_ggc)
- Allocator <value_type> ::data_free (m_entries);
- else
- ggc_free (m_entries);
- m_entries = alloc_entries (nsize);
- m_size = nsize;
- m_size_prime_index = nindex;
- }
- else
- memset (entries, 0, size * sizeof (value_type));
- m_n_deleted = 0;
- m_n_elements = 0;
- }
- /* This function clears a specified SLOT in a hash table. It is
- useful when you've already done the lookup and don't want to do it
- again. */
- template<typename Descriptor, template<typename Type> class Allocator>
- void
- hash_table<Descriptor, Allocator, true>::clear_slot (value_type *slot)
- {
- gcc_checking_assert (!(slot < m_entries || slot >= m_entries + size ()
- || is_empty (*slot) || is_deleted (*slot)));
- Descriptor::remove (*slot);
- mark_deleted (*slot);
- m_n_deleted++;
- }
- /* This function searches for a hash table entry equal to the given
- COMPARABLE element starting with the given HASH value. It cannot
- be used to insert or delete an element. */
- template<typename Descriptor, template<typename Type> class Allocator>
- typename hash_table<Descriptor, Allocator, true>::value_type &
- hash_table<Descriptor, Allocator, true>
- ::find_with_hash (const compare_type &comparable, hashval_t hash)
- {
- m_searches++;
- size_t size = m_size;
- hashval_t index = hash_table_mod1 (hash, m_size_prime_index);
- value_type *entry = &m_entries[index];
- if (is_empty (*entry)
- || (!is_deleted (*entry) && Descriptor::equal (*entry, comparable)))
- return *entry;
- hashval_t hash2 = hash_table_mod2 (hash, m_size_prime_index);
- for (;;)
- {
- m_collisions++;
- index += hash2;
- if (index >= size)
- index -= size;
- entry = &m_entries[index];
- if (is_empty (*entry)
- || (!is_deleted (*entry) && Descriptor::equal (*entry, comparable)))
- return *entry;
- }
- }
- /* This function searches for a hash table slot containing an entry
- equal to the given COMPARABLE element and starting with the given
- HASH. To delete an entry, call this with insert=NO_INSERT, then
- call clear_slot on the slot returned (possibly after doing some
- checks). To insert an entry, call this with insert=INSERT, then
- write the value you want into the returned slot. When inserting an
- entry, NULL may be returned if memory allocation fails. */
- template<typename Descriptor, template<typename Type> class Allocator>
- typename hash_table<Descriptor, Allocator, true>::value_type *
- hash_table<Descriptor, Allocator, true>
- ::find_slot_with_hash (const compare_type &comparable, hashval_t hash,
- enum insert_option insert)
- {
- if (insert == INSERT && m_size * 3 <= m_n_elements * 4)
- expand ();
- m_searches++;
- value_type *first_deleted_slot = NULL;
- hashval_t index = hash_table_mod1 (hash, m_size_prime_index);
- hashval_t hash2 = hash_table_mod2 (hash, m_size_prime_index);
- value_type *entry = &m_entries[index];
- size_t size = m_size;
- if (is_empty (*entry))
- goto empty_entry;
- else if (is_deleted (*entry))
- first_deleted_slot = &m_entries[index];
- else if (Descriptor::equal (*entry, comparable))
- return &m_entries[index];
- for (;;)
- {
- m_collisions++;
- index += hash2;
- if (index >= size)
- index -= size;
- entry = &m_entries[index];
- if (is_empty (*entry))
- goto empty_entry;
- else if (is_deleted (*entry))
- {
- if (!first_deleted_slot)
- first_deleted_slot = &m_entries[index];
- }
- else if (Descriptor::equal (*entry, comparable))
- return &m_entries[index];
- }
- empty_entry:
- if (insert == NO_INSERT)
- return NULL;
- if (first_deleted_slot)
- {
- m_n_deleted--;
- mark_empty (*first_deleted_slot);
- return first_deleted_slot;
- }
- m_n_elements++;
- return &m_entries[index];
- }
- /* This function deletes an element with the given COMPARABLE value
- from hash table starting with the given HASH. If there is no
- matching element in the hash table, this function does nothing. */
- template<typename Descriptor, template<typename Type> class Allocator>
- void
- hash_table<Descriptor, Allocator, true>
- ::remove_elt_with_hash (const compare_type &comparable, hashval_t hash)
- {
- value_type *slot = find_slot_with_hash (comparable, hash, NO_INSERT);
- if (is_empty (*slot))
- return;
- Descriptor::remove (*slot);
- mark_deleted (*slot);
- m_n_deleted++;
- }
- /* This function scans over the entire hash table calling CALLBACK for
- each live entry. If CALLBACK returns false, the iteration stops.
- ARGUMENT is passed as CALLBACK's second argument. */
- template<typename Descriptor,
- template<typename Type> class Allocator>
- template<typename Argument,
- int (*Callback) (typename hash_table<Descriptor, Allocator,
- true>::value_type *slot,
- Argument argument)>
- void
- hash_table<Descriptor, Allocator, true>::traverse_noresize (Argument argument)
- {
- value_type *slot = m_entries;
- value_type *limit = slot + size ();
- do
- {
- value_type &x = *slot;
- if (!is_empty (x) && !is_deleted (x))
- if (! Callback (slot, argument))
- break;
- }
- while (++slot < limit);
- }
- /* Like traverse_noresize, but does resize the table when it is too empty
- to improve effectivity of subsequent calls. */
- template <typename Descriptor,
- template <typename Type> class Allocator>
- template <typename Argument,
- int (*Callback) (typename hash_table<Descriptor, Allocator,
- true>::value_type *slot,
- Argument argument)>
- void
- hash_table<Descriptor, Allocator, true>::traverse (Argument argument)
- {
- size_t size = m_size;
- if (elements () * 8 < size && size > 32)
- expand ();
- traverse_noresize <Argument, Callback> (argument);
- }
- /* Slide down the iterator slots until an active entry is found. */
- template<typename Descriptor, template<typename Type> class Allocator>
- void
- hash_table<Descriptor, Allocator, true>::iterator::slide ()
- {
- for ( ; m_slot < m_limit; ++m_slot )
- {
- value_type &x = *m_slot;
- if (!is_empty (x) && !is_deleted (x))
- return;
- }
- m_slot = NULL;
- m_limit = NULL;
- }
- /* Bump the iterator. */
- template<typename Descriptor, template<typename Type> class Allocator>
- inline typename hash_table<Descriptor, Allocator, true>::iterator &
- hash_table<Descriptor, Allocator, true>::iterator::operator ++ ()
- {
- ++m_slot;
- slide ();
- return *this;
- }
- /* Iterate through the elements of hash_table HTAB,
- using hash_table <....>::iterator ITER,
- storing each element in RESULT, which is of type TYPE. */
- #define FOR_EACH_HASH_TABLE_ELEMENT(HTAB, RESULT, TYPE, ITER) \
- for ((ITER) = (HTAB).begin (); \
- (ITER) != (HTAB).end () ? (RESULT = *(ITER) , true) : false; \
- ++(ITER))
- /* ggc walking routines. */
- template<typename E>
- static inline void
- gt_ggc_mx (hash_table<E> *h)
- {
- typedef hash_table<E> table;
- if (!ggc_test_and_set_mark (h->m_entries))
- return;
- for (size_t i = 0; i < h->m_size; i++)
- {
- if (table::is_empty (h->m_entries[i])
- || table::is_deleted (h->m_entries[i]))
- continue;
- E::ggc_mx (h->m_entries[i]);
- }
- }
- template<typename D>
- static inline void
- hashtab_entry_note_pointers (void *obj, void *h, gt_pointer_operator op,
- void *cookie)
- {
- hash_table<D> *map = static_cast<hash_table<D> *> (h);
- gcc_checking_assert (map->m_entries == obj);
- for (size_t i = 0; i < map->m_size; i++)
- {
- typedef hash_table<D> table;
- if (table::is_empty (map->m_entries[i])
- || table::is_deleted (map->m_entries[i]))
- continue;
- D::pch_nx (map->m_entries[i], op, cookie);
- }
- }
- template<typename D>
- static void
- gt_pch_nx (hash_table<D> *h)
- {
- bool success
- = gt_pch_note_object (h->m_entries, h, hashtab_entry_note_pointers<D>);
- gcc_checking_assert (success);
- for (size_t i = 0; i < h->m_size; i++)
- {
- if (hash_table<D>::is_empty (h->m_entries[i])
- || hash_table<D>::is_deleted (h->m_entries[i]))
- continue;
- D::pch_nx (h->m_entries[i]);
- }
- }
- template<typename D>
- static inline void
- gt_pch_nx (hash_table<D> *h, gt_pointer_operator op, void *cookie)
- {
- op (&h->m_entries, cookie);
- }
- template<typename H>
- inline void
- gt_cleare_cache (hash_table<H> *h)
- {
- if (!h)
- return;
- for (typename hash_table<H>::iterator iter = h->begin (); iter != h->end ();
- ++iter)
- H::handle_cache_entry (*iter);
- }
- #endif /* TYPED_HASHTAB_H */
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