/* Copyright 2014-2015 Samsung Electronics Co., Ltd.
 *
 * 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.
 */

#ifndef BYTECODE_DATA_H
#define BYTECODE_DATA_H

#include "opcodes.h"
#include "lit-id-hash-table.h"
#include "mem-allocator.h"

/*
 * All literals are kept in the 'literals' array.
 * Literal structure doesn't hold real string. All program-specific strings
 * are kept in the 'strings_buffer' and literal has pointer to this buffer.
 *
 * Literal id is its index in 'literals' array of bytecode_data_t structure.
 *
 * Bytecode, which is kept in the 'instrs' field, is divided into blocks
 * of 'BLOCK_SIZE' operands. Every block has its own numbering of literals.
 * Literal uid could be in range [0, 127] in every block.
 *
 * To map uid to literal id 'lit_id_hash' table is used.
 */
#define BLOCK_SIZE 64

/**
 * Header of byte-code memory region, containing byte-code array and literal identifiers hash table
 */
typedef struct __attribute__ ((aligned (MEM_ALIGNMENT)))
{
  mem_cpointer_t lit_id_hash_cp; /**< pointer to literal identifiers hash table
                                  *   See also: lit_id_hash_table_init */
  mem_cpointer_t next_instrs_cp; /**< pointer to next byte-code memory region */
  vm_instr_counter_t instructions_number; /**< number of instructions in the byte-code array */
} insts_data_header_t;

typedef struct
{
  const ecma_char_t *strings_buffer;
  const vm_instr_t *instrs_p;
  vm_instr_counter_t instrs_count;
} bytecode_data_t;

/**
 * Macros to get a pointer to bytecode header by pointer to instructions array start
 */
#define GET_BYTECODE_HEADER(instrs) ((insts_data_header_t *) (((uint8_t *) (instrs)) - sizeof (insts_data_header_t)))

/**
 * Macros to get a hash table corresponding to a bytecode region
 */
#define GET_HASH_TABLE_FOR_BYTECODE(instrs) (MEM_CP_GET_POINTER (lit_id_hash_table, \
                                                                 GET_BYTECODE_HEADER (instrs)->lit_id_hash_cp))


#endif // BYTECODE_DATA_H