jerryscript/jerry-core/jcontext/jcontext.h

/* Copyright JS Foundation and other contributors, http://js.foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * Memory context for JerryScript
 */
#ifndef JCONTEXT_H
#define JCONTEXT_H

#include "ecma-builtins.h"
#include "jmem-allocator.h"
#include "jmem-config.h"
#include "re-bytecode.h"
#include "vm-defines.h"

/** \addtogroup context Context
 * @{
 */

/**
 * First member of the jerry context
 */
#define JERRY_CONTEXT_FIRST_MEMBER ecma_builtin_objects

/**
 * JerryScript context
 *
 * The purpose of this header is storing
 * all global variables for Jerry
 */
typedef struct
{
  /* Update JERRY_CONTEXT_FIRST_MEMBER if the first member changes */
  ecma_object_t *ecma_builtin_objects[ECMA_BUILTIN_ID__COUNT]; /**< pointer to instances of built-in objects */
#ifndef CONFIG_DISABLE_REGEXP_BUILTIN
  const re_compiled_code_t *re_cache[RE_CACHE_SIZE]; /**< regex cache */
#endif /* !CONFIG_DISABLE_REGEXP_BUILTIN */
  ecma_object_t *ecma_gc_objects_lists[ECMA_GC_COLOR__COUNT]; /**< List of marked (visited during
                                                               *   current GC session) and umarked objects */
  jmem_heap_free_t *jmem_heap_list_skip_p; /**< This is used to speed up deallocation. */
  jmem_pools_chunk_t *jmem_free_8_byte_chunk_p; /**< list of free eight byte pool chunks */
#ifdef JERRY_CPOINTER_32_BIT
  jmem_pools_chunk_t *jmem_free_16_byte_chunk_p; /**< list of free sixteen byte pool chunks */
#endif /* JERRY_CPOINTER_32_BIT */
  jmem_free_unused_memory_callback_t jmem_free_unused_memory_callback; /**< Callback for freeing up memory. */
  const lit_utf8_byte_t **lit_magic_string_ex_array; /**< array of external magic strings */
  const lit_utf8_size_t *lit_magic_string_ex_sizes; /**< external magic string lengths */
  ecma_lit_storage_item_t *string_list_first_p; /**< first item of the literal string list */
  ecma_lit_storage_item_t *number_list_first_p; /**< first item of the literal number list */
  ecma_object_t *ecma_global_lex_env_p; /**< global lexical environment */
  vm_frame_ctx_t *vm_top_context_p; /**< top (current) interpreter context */
  size_t ecma_gc_objects_number; /**< number of currently allocated objects */
  size_t ecma_gc_new_objects; /**< number of newly allocated objects since last GC session */
  size_t jmem_heap_allocated_size; /**< size of allocated regions */
  size_t jmem_heap_limit; /**< current limit of heap usage, that is upon being reached,
                           *   causes call of "try give memory back" callbacks */
  uint32_t lit_magic_string_ex_count; /**< external magic strings count */
  uint32_t jerry_init_flags; /**< run-time configuration flags */
  uint8_t ecma_gc_visited_flip_flag; /**< current state of an object's visited flag */
  uint8_t is_direct_eval_form_call; /**< direct call from eval */
  uint8_t jerry_api_available; /**< API availability flag */

#ifndef CONFIG_ECMA_PROPERTY_HASHMAP_DISABLE
  uint8_t ecma_prop_hashmap_alloc_state; /**< property hashmap allocation state: 0-4,
                                          *   if !0 property hashmap allocation is disabled */
  bool ecma_prop_hashmap_alloc_last_is_hs_gc; /**< true, if and only if the last gc action was a high severity gc */
#endif /* !CONFIG_ECMA_PROPERTY_HASHMAP_DISABLE */

#ifndef CONFIG_DISABLE_REGEXP_BUILTIN
  uint8_t re_cache_idx; /**< evicted item index when regex cache is full (round-robin) */
#endif /* !CONFIG_DISABLE_REGEXP_BUILTIN */

#ifdef JMEM_STATS
  jmem_heap_stats_t jmem_heap_stats; /**< heap's memory usage statistics */
  jmem_pools_stats_t jmem_pools_stats; /**< pools' memory usage statistics */
#endif /* JMEM_STATS */

#ifdef JERRY_VALGRIND_FREYA
  uint8_t valgrind_freya_mempool_request; /**< Tells whether a pool manager
                                           *   allocator request is in progress */
#endif /* JERRY_VALGRIND_FREYA */
} jerry_context_t;

/**
 * Calculate heap area size, leaving space for a pointer to the free list
 */
#define JMEM_HEAP_AREA_SIZE (JMEM_HEAP_SIZE - JMEM_ALIGNMENT)

/**
 * Heap structure
 *
 * Memory blocks returned by the allocator must not start from the
 * beginning of the heap area because offset 0 is reserved for
 * JMEM_CP_NULL. This special constant is used in several places,
 * e.g. it marks the end of the property chain list, so it cannot
 * be eliminated from the project. Although the allocator cannot
 * use the first 8 bytes of the heap, nothing prevents to use it
 * for other purposes. Currently the free region start is stored
 * there.
 */
typedef struct
{
  jmem_heap_free_t first; /**< first node in free region list */
  uint8_t area[JMEM_HEAP_AREA_SIZE]; /**< heap area */
} jmem_heap_t;

#ifndef CONFIG_ECMA_LCACHE_DISABLE

/**
 * JerryScript global hash table for caching the last access of properties.
 */
typedef struct
{
  /**
   * Hash table
   */
  ecma_lcache_hash_entry_t table[ECMA_LCACHE_HASH_ROWS_COUNT][ECMA_LCACHE_HASH_ROW_LENGTH];
} jerry_hash_table_t;

#endif /* !CONFIG_ECMA_LCACHE_DISABLE */

/**
 * Global context.
 */
extern jerry_context_t jerry_global_context;

/**
 * Global heap.
 */
extern jmem_heap_t jerry_global_heap;

#ifndef CONFIG_ECMA_LCACHE_DISABLE

/**
 * Global hash table.
 */
extern jerry_hash_table_t jerry_global_hash_table;

#endif /* !CONFIG_ECMA_LCACHE_DISABLE */

/**
 * Provides a reference to a field in the current context.
 */
#define JERRY_CONTEXT(field) (jerry_global_context.field)

/**
 * Provides a reference to the area field of the heap.
 */
#define JERRY_HEAP_CONTEXT(field) (jerry_global_heap.field)

#ifndef CONFIG_ECMA_LCACHE_DISABLE

/**
 * Provides a reference to the global hash table.
 */
#define JERRY_HASH_TABLE_CONTEXT(field) (jerry_global_hash_table.field)

#endif /* !CONFIG_ECMA_LCACHE_DISABLE */

/**
 * @}
 */

#endif /* !JCONTEXT_H */