| /* Functions to support a pool of allocatable objects |
| Copyright (C) 1997-2022 Free Software Foundation, Inc. |
| Contributed by Daniel Berlin <dan@cgsoftware.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/>. */ |
| #ifndef ALLOC_POOL_H |
| #define ALLOC_POOL_H |
| |
| #include "memory-block.h" |
| #include "options.h" // for flag_checking |
| |
| extern void dump_alloc_pool_statistics (void); |
| |
| /* Flag indicates whether memory statistics are gathered any longer. */ |
| extern bool after_memory_report; |
| |
| typedef unsigned long ALLOC_POOL_ID_TYPE; |
| |
| /* Last used ID. */ |
| extern ALLOC_POOL_ID_TYPE last_id; |
| |
| /* Pool allocator memory usage. */ |
| class pool_usage: public mem_usage |
| { |
| public: |
| /* Default contructor. */ |
| pool_usage (): m_element_size (0), m_pool_name ("") {} |
| /* Constructor. */ |
| pool_usage (size_t allocated, size_t times, size_t peak, |
| size_t instances, size_t element_size, |
| const char *pool_name) |
| : mem_usage (allocated, times, peak, instances), |
| m_element_size (element_size), |
| m_pool_name (pool_name) {} |
| |
| /* Sum the usage with SECOND usage. */ |
| pool_usage |
| operator+ (const pool_usage &second) |
| { |
| return pool_usage (m_allocated + second.m_allocated, |
| m_times + second.m_times, |
| m_peak + second.m_peak, |
| m_instances + second.m_instances, |
| m_element_size, m_pool_name); |
| } |
| |
| /* Dump usage coupled to LOC location, where TOTAL is sum of all rows. */ |
| inline void |
| dump (mem_location *loc, const mem_usage &total) const |
| { |
| char *location_string = loc->to_string (); |
| |
| fprintf (stderr, "%-32s%-48s " PRsa(5) PRsa(9) ":%5.1f%%" |
| PRsa(9) PRsa(9) ":%5.1f%%%12" PRIu64 "\n", |
| m_pool_name, location_string, |
| SIZE_AMOUNT (m_instances), |
| SIZE_AMOUNT (m_allocated), |
| get_percent (m_allocated, total.m_allocated), |
| SIZE_AMOUNT (m_peak), |
| SIZE_AMOUNT (m_times), |
| get_percent (m_times, total.m_times), |
| (uint64_t)m_element_size); |
| |
| free (location_string); |
| } |
| |
| /* Dump header with NAME. */ |
| static inline void |
| dump_header (const char *name) |
| { |
| fprintf (stderr, "%-32s%-48s %6s%11s%16s%17s%12s\n", "Pool name", name, |
| "Pools", "Leak", "Peak", "Times", "Elt size"); |
| } |
| |
| /* Dump footer. */ |
| inline void |
| dump_footer () |
| { |
| fprintf (stderr, "%s" PRsa(82) PRsa(10) "\n", "Total", |
| SIZE_AMOUNT (m_instances), SIZE_AMOUNT (m_allocated)); |
| } |
| |
| /* Element size. */ |
| size_t m_element_size; |
| /* Pool name. */ |
| const char *m_pool_name; |
| }; |
| |
| extern mem_alloc_description<pool_usage> pool_allocator_usage; |
| |
| #if 0 |
| /* If a pool with custom block size is needed, one might use the following |
| template. An instance of this template can be used as a parameter for |
| instantiating base_pool_allocator template: |
| |
| typedef custom_block_allocator <128*1024> huge_block_allocator; |
| ... |
| static base_pool_allocator <huge_block_allocator> |
| value_pool ("value", 16384); |
| |
| Right now it's not used anywhere in the code, and is given here as an |
| example). */ |
| |
| template <size_t BlockSize> |
| class custom_block_allocator |
| { |
| public: |
| static const size_t block_size = BlockSize; |
| |
| static inline void * |
| allocate () ATTRIBUTE_MALLOC |
| { |
| return XNEWVEC (char, BlockSize); |
| } |
| |
| static inline void |
| release (void *block) |
| { |
| XDELETEVEC (block); |
| } |
| }; |
| #endif |
| |
| /* Generic pool allocator. */ |
| |
| template <typename TBlockAllocator> |
| class base_pool_allocator |
| { |
| public: |
| /* Default constructor for pool allocator called NAME. */ |
| base_pool_allocator (const char *name, size_t size CXX_MEM_STAT_INFO); |
| ~base_pool_allocator (); |
| void release (); |
| void release_if_empty (); |
| void *allocate () ATTRIBUTE_MALLOC; |
| void remove (void *object); |
| size_t num_elts_current (); |
| |
| private: |
| struct allocation_pool_list |
| { |
| allocation_pool_list *next; |
| }; |
| |
| /* Initialize a pool allocator. */ |
| void initialize (); |
| |
| struct allocation_object |
| { |
| #if CHECKING_P |
| /* The ID of alloc pool which the object was allocated from. */ |
| ALLOC_POOL_ID_TYPE id; |
| #endif |
| |
| union |
| { |
| /* The data of the object. */ |
| char data[1]; |
| |
| /* Because we want any type of data to be well aligned after the ID, |
| the following elements are here. They are never accessed so |
| the allocated object may be even smaller than this structure. |
| We do not care about alignment for floating-point types. */ |
| char *align_p; |
| int64_t align_i; |
| } u; |
| |
| #if CHECKING_P |
| static inline allocation_object* |
| get_instance (void *data_ptr) |
| { |
| return (allocation_object *)(((char *)(data_ptr)) |
| - offsetof (allocation_object, |
| u.data)); |
| } |
| #endif |
| |
| static inline void* |
| get_data (void *instance_ptr) |
| { |
| return (void*)(((allocation_object *) instance_ptr)->u.data); |
| } |
| }; |
| |
| /* Align X to 8. */ |
| static inline size_t |
| align_eight (size_t x) |
| { |
| return (((x+7) >> 3) << 3); |
| } |
| |
| const char *m_name; |
| ALLOC_POOL_ID_TYPE m_id; |
| size_t m_elts_per_block; |
| |
| /* These are the elements that have been allocated at least once |
| and freed. */ |
| allocation_pool_list *m_returned_free_list; |
| |
| /* These are the elements that have not yet been allocated out of |
| the last block obtained from XNEWVEC. */ |
| char* m_virgin_free_list; |
| |
| /* The number of elements in the virgin_free_list that can be |
| allocated before needing another block. */ |
| size_t m_virgin_elts_remaining; |
| /* The number of elements that are allocated. */ |
| size_t m_elts_allocated; |
| /* The number of elements that are released. */ |
| size_t m_elts_free; |
| /* The number of allocated blocks. */ |
| size_t m_blocks_allocated; |
| /* List of blocks that are used to allocate new objects. */ |
| allocation_pool_list *m_block_list; |
| /* Size of a pool elements in bytes. */ |
| size_t m_elt_size; |
| /* Size in bytes that should be allocated for each element. */ |
| size_t m_size; |
| /* Flag if a pool allocator is initialized. */ |
| bool m_initialized; |
| /* Memory allocation location. */ |
| mem_location m_location; |
| }; |
| |
| template <typename TBlockAllocator> |
| inline |
| base_pool_allocator <TBlockAllocator>::base_pool_allocator ( |
| const char *name, size_t size MEM_STAT_DECL): |
| m_name (name), m_id (0), m_elts_per_block (0), m_returned_free_list (NULL), |
| m_virgin_free_list (NULL), m_virgin_elts_remaining (0), m_elts_allocated (0), |
| m_elts_free (0), m_blocks_allocated (0), m_block_list (NULL), m_elt_size (0), |
| m_size (size), m_initialized (false), |
| m_location (ALLOC_POOL_ORIGIN, false PASS_MEM_STAT) {} |
| |
| /* Initialize a pool allocator. */ |
| |
| template <typename TBlockAllocator> |
| inline void |
| base_pool_allocator <TBlockAllocator>::initialize () |
| { |
| gcc_checking_assert (!m_initialized); |
| m_initialized = true; |
| |
| size_t size = m_size; |
| |
| gcc_checking_assert (m_name); |
| gcc_checking_assert (m_size); |
| |
| /* Make size large enough to store the list header. */ |
| if (size < sizeof (allocation_pool_list*)) |
| size = sizeof (allocation_pool_list*); |
| |
| /* Now align the size to a multiple of 8. */ |
| size = align_eight (size); |
| |
| /* Add the aligned size of ID. */ |
| size += offsetof (allocation_object, u.data); |
| |
| m_elt_size = size; |
| |
| if (GATHER_STATISTICS) |
| { |
| pool_usage *u = pool_allocator_usage.register_descriptor |
| (this, new mem_location (m_location)); |
| |
| u->m_element_size = m_elt_size; |
| u->m_pool_name = m_name; |
| } |
| |
| /* List header size should be a multiple of 8. */ |
| size_t header_size = align_eight (sizeof (allocation_pool_list)); |
| |
| m_elts_per_block = (TBlockAllocator::block_size - header_size) / size; |
| gcc_checking_assert (m_elts_per_block != 0); |
| |
| /* Increase the last used ID and use it for this pool. |
| ID == 0 is used for free elements of pool so skip it. */ |
| last_id++; |
| if (last_id == 0) |
| last_id++; |
| |
| m_id = last_id; |
| } |
| |
| /* Free all memory allocated for the given memory pool. */ |
| template <typename TBlockAllocator> |
| inline void |
| base_pool_allocator <TBlockAllocator>::release () |
| { |
| if (!m_initialized) |
| return; |
| |
| allocation_pool_list *block, *next_block; |
| |
| /* Free each block allocated to the pool. */ |
| for (block = m_block_list; block != NULL; block = next_block) |
| { |
| next_block = block->next; |
| TBlockAllocator::release (block); |
| } |
| |
| if (GATHER_STATISTICS && !after_memory_report) |
| { |
| pool_allocator_usage.release_instance_overhead |
| (this, (m_elts_allocated - m_elts_free) * m_elt_size); |
| } |
| |
| m_returned_free_list = NULL; |
| m_virgin_free_list = NULL; |
| m_virgin_elts_remaining = 0; |
| m_elts_allocated = 0; |
| m_elts_free = 0; |
| m_blocks_allocated = 0; |
| m_block_list = NULL; |
| } |
| |
| template <typename TBlockAllocator> |
| inline void |
| base_pool_allocator <TBlockAllocator>::release_if_empty () |
| { |
| if (m_elts_free == m_elts_allocated) |
| release (); |
| } |
| |
| template <typename TBlockAllocator> |
| inline base_pool_allocator <TBlockAllocator>::~base_pool_allocator () |
| { |
| release (); |
| } |
| |
| /* Allocates one element from the pool specified. */ |
| template <typename TBlockAllocator> |
| inline void* |
| base_pool_allocator <TBlockAllocator>::allocate () |
| { |
| if (!m_initialized) |
| initialize (); |
| |
| allocation_pool_list *header; |
| #ifdef ENABLE_VALGRIND_ANNOTATIONS |
| int size; |
| #endif |
| |
| if (GATHER_STATISTICS) |
| { |
| pool_allocator_usage.register_instance_overhead (m_elt_size, this); |
| } |
| |
| #ifdef ENABLE_VALGRIND_ANNOTATIONS |
| size = m_elt_size - offsetof (allocation_object, u.data); |
| #endif |
| |
| /* If there are no more free elements, make some more!. */ |
| if (!m_returned_free_list) |
| { |
| char *block; |
| if (!m_virgin_elts_remaining) |
| { |
| allocation_pool_list *block_header; |
| |
| /* Make the block. */ |
| block = reinterpret_cast<char *> (TBlockAllocator::allocate ()); |
| block_header = new (block) allocation_pool_list; |
| block += align_eight (sizeof (allocation_pool_list)); |
| |
| /* Throw it on the block list. */ |
| block_header->next = m_block_list; |
| m_block_list = block_header; |
| |
| /* Make the block available for allocation. */ |
| m_virgin_free_list = block; |
| m_virgin_elts_remaining = m_elts_per_block; |
| |
| /* Also update the number of elements we have free/allocated, and |
| increment the allocated block count. */ |
| m_elts_allocated += m_elts_per_block; |
| m_elts_free += m_elts_per_block; |
| m_blocks_allocated += 1; |
| } |
| |
| /* We now know that we can take the first elt off the virgin list and |
| put it on the returned list. */ |
| block = m_virgin_free_list; |
| header = (allocation_pool_list*) allocation_object::get_data (block); |
| header->next = NULL; |
| |
| /* Mark the element to be free. */ |
| #if CHECKING_P |
| ((allocation_object*) block)->id = 0; |
| #endif |
| VALGRIND_DISCARD (VALGRIND_MAKE_MEM_NOACCESS (header,size)); |
| m_returned_free_list = header; |
| m_virgin_free_list += m_elt_size; |
| m_virgin_elts_remaining--; |
| |
| } |
| |
| /* Pull the first free element from the free list, and return it. */ |
| header = m_returned_free_list; |
| VALGRIND_DISCARD (VALGRIND_MAKE_MEM_DEFINED (header, sizeof (*header))); |
| m_returned_free_list = header->next; |
| m_elts_free--; |
| |
| /* Set the ID for element. */ |
| #if CHECKING_P |
| allocation_object::get_instance (header)->id = m_id; |
| #endif |
| VALGRIND_DISCARD (VALGRIND_MAKE_MEM_UNDEFINED (header, size)); |
| |
| return (void *)(header); |
| } |
| |
| /* Puts PTR back on POOL's free list. */ |
| template <typename TBlockAllocator> |
| inline void |
| base_pool_allocator <TBlockAllocator>::remove (void *object) |
| { |
| int size = m_elt_size - offsetof (allocation_object, u.data); |
| |
| if (flag_checking) |
| { |
| gcc_assert (m_initialized); |
| gcc_assert (object |
| /* Check if we free more than we allocated. */ |
| && m_elts_free < m_elts_allocated); |
| #if CHECKING_P |
| /* Check whether the PTR was allocated from POOL. */ |
| gcc_assert (m_id == allocation_object::get_instance (object)->id); |
| #endif |
| |
| memset (object, 0xaf, size); |
| } |
| |
| #if CHECKING_P |
| /* Mark the element to be free. */ |
| allocation_object::get_instance (object)->id = 0; |
| #endif |
| |
| allocation_pool_list *header = new (object) allocation_pool_list; |
| header->next = m_returned_free_list; |
| m_returned_free_list = header; |
| VALGRIND_DISCARD (VALGRIND_MAKE_MEM_NOACCESS (object, size)); |
| m_elts_free++; |
| |
| if (GATHER_STATISTICS) |
| { |
| pool_allocator_usage.release_instance_overhead (this, m_elt_size); |
| } |
| } |
| |
| /* Number of elements currently active (not returned to pool). Used for cheap |
| consistency checks. */ |
| template <typename TBlockAllocator> |
| inline size_t |
| base_pool_allocator <TBlockAllocator>::num_elts_current () |
| { |
| return m_elts_allocated - m_elts_free; |
| } |
| |
| /* Specialization of base_pool_allocator which should be used in most cases. |
| Another specialization may be needed, if object size is greater than |
| memory_block_pool::block_size (64 KB). */ |
| typedef base_pool_allocator <memory_block_pool> pool_allocator; |
| |
| /* Type based memory pool allocator. */ |
| template <typename T> |
| class object_allocator |
| { |
| public: |
| /* Default constructor for pool allocator called NAME. */ |
| object_allocator (const char *name CXX_MEM_STAT_INFO): |
| m_allocator (name, sizeof (T) PASS_MEM_STAT) {} |
| |
| inline void |
| release () |
| { |
| m_allocator.release (); |
| } |
| |
| inline void release_if_empty () |
| { |
| m_allocator.release_if_empty (); |
| } |
| |
| |
| /* Allocate memory for instance of type T and call a default constructor. */ |
| |
| inline T * |
| allocate () ATTRIBUTE_MALLOC |
| { |
| return ::new (m_allocator.allocate ()) T; |
| } |
| |
| /* Allocate memory for instance of type T and return void * that |
| could be used in situations where a default constructor is not provided |
| by the class T. */ |
| |
| inline void * |
| allocate_raw () ATTRIBUTE_MALLOC |
| { |
| return m_allocator.allocate (); |
| } |
| |
| inline void |
| remove (T *object) |
| { |
| /* Call destructor. */ |
| object->~T (); |
| |
| m_allocator.remove (object); |
| } |
| |
| inline void |
| remove_raw (void *object) |
| { |
| m_allocator.remove (object); |
| } |
| |
| inline size_t |
| num_elts_current () |
| { |
| return m_allocator.num_elts_current (); |
| } |
| |
| private: |
| pool_allocator m_allocator; |
| }; |
| |
| /* Store information about each particular alloc_pool. Note that this |
| will underestimate the amount the amount of storage used by a small amount: |
| 1) The overhead in a pool is not accounted for. |
| 2) The unallocated elements in a block are not accounted for. Note |
| that this can at worst case be one element smaller that the block |
| size for that pool. */ |
| struct alloc_pool_descriptor |
| { |
| /* Number of pools allocated. */ |
| unsigned long created; |
| /* Gross allocated storage. */ |
| unsigned long allocated; |
| /* Amount of currently active storage. */ |
| unsigned long current; |
| /* Peak amount of storage used. */ |
| unsigned long peak; |
| /* Size of element in the pool. */ |
| int elt_size; |
| }; |
| |
| /* Helper for classes that do not provide default ctor. */ |
| |
| template <typename T> |
| inline void * |
| operator new (size_t, object_allocator<T> &a) |
| { |
| return a.allocate_raw (); |
| } |
| |
| /* Hashtable mapping alloc_pool names to descriptors. */ |
| extern hash_map<const char *, alloc_pool_descriptor> *alloc_pool_hash; |
| |
| |
| #endif |