jerryscript/src/libecmaoperations/ecma-comparison.c

/* Copyright 2014 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.
 */

#include "ecma-comparison.h"
#include "ecma-conversion.h"
#include "ecma-globals.h"
#include "ecma-try-catch-macro.h"
#include "globals.h"

/** \addtogroup ecma ---TODO---
 * @{
 * 
 * \addtogroup ecmacomparison ECMA comparison
 * @{
 */

/**
 * ECMA abstract equality comparison routine.
 *
 * See also: ECMA-262 v5, 11.9.3
 *
 * @return true - if values are equal,
 *         false - otherwise.
 */
bool
ecma_op_abstract_equality_compare(ecma_value_t x, /**< first operand */
                                  ecma_value_t y) /**< second operand */
{
  const bool is_x_undefined = ecma_is_value_undefined( x);
  const bool is_x_null = ecma_is_value_null( x);
  const bool is_x_boolean = ecma_is_value_boolean( x);
  const bool is_x_number = ( x.value_type == ECMA_TYPE_NUMBER );
  const bool is_x_string = ( x.value_type == ECMA_TYPE_STRING );
  const bool is_x_object = ( x.value_type == ECMA_TYPE_OBJECT );

  const bool is_y_undefined = ecma_is_value_undefined( y);
  const bool is_y_null = ecma_is_value_null( y);
  const bool is_y_boolean = ecma_is_value_boolean( y);
  const bool is_y_number = ( y.value_type == ECMA_TYPE_NUMBER );
  const bool is_y_string = ( y.value_type == ECMA_TYPE_STRING );
  const bool is_y_object = ( y.value_type == ECMA_TYPE_OBJECT );

  const bool is_types_equal = ( ( is_x_undefined && is_y_undefined )
                                || ( is_x_null && is_y_null )
                                || ( is_x_boolean && is_y_boolean )
                                || ( is_x_number && is_y_number )
                                || ( is_x_string && is_y_string )
                                || ( is_x_object && is_y_object ) );

  if ( is_types_equal )
  {
    // 1.

    if ( is_x_undefined
         || is_x_null )
    {
      // a., b.
      return true;
    } else if ( is_x_number )
    { // c.
      ecma_number_t x_num = *(ecma_number_t*)( ecma_get_pointer(x.value) );
      ecma_number_t y_num = *(ecma_number_t*)( ecma_get_pointer(y.value) );

      TODO( Implement according to ECMA );

      return (x_num == y_num);
    } else if ( is_x_string )
    { // d.
      ecma_array_first_chunk_t* x_str = (ecma_array_first_chunk_t*)( ecma_get_pointer(x.value) );
      ecma_array_first_chunk_t* y_str = (ecma_array_first_chunk_t*)( ecma_get_pointer(y.value) );

      return ecma_compare_ecma_string_to_ecma_string( x_str, y_str);
    } else if ( is_x_boolean )
    { // e.
      return ( x.value == y.value );
    } else
    { // f.
      JERRY_ASSERT( is_x_object );
      
      return ( x.value == y.value );
    }
  } else if ( ( is_x_null && is_y_undefined )
              || ( is_x_undefined && is_y_null ) )
  { // 2., 3.
    return true;
  } else
  {
    JERRY_UNIMPLEMENTED();
  }
} /* ecma_op_abstract_equality_compare */

/**
 * ECMA abstract relational comparison routine.
 *
 * See also: ECMA-262 v5, 11.8.5
 *
 * @return completion value
 *         Returned value must be freed with ecma_free_completion_value
 */
ecma_completion_value_t
ecma_op_abstract_relational_compare(ecma_value_t x, /**< first operand */
                                    ecma_value_t y, /**< second operand */
                                    bool left_first) /**< 'LeftFirst' flag */
{
  ecma_completion_value_t ret_value, px, py;

  ecma_value_t first_converted_value = left_first ? x : y;
  ecma_value_t second_converted_value = left_first ? y : x;

  // 1., 2.
  ECMA_TRY_CATCH( prim_first_converted_value, ecma_op_to_primitive( first_converted_value, ECMA_PREFERRED_TYPE_NUMBER), ret_value);
  ECMA_TRY_CATCH( prim_second_converted_value, ecma_op_to_primitive( second_converted_value, ECMA_PREFERRED_TYPE_NUMBER), ret_value);

  px = left_first ? prim_first_converted_value : prim_second_converted_value;
  py = left_first ? prim_second_converted_value : prim_first_converted_value;

  const bool is_px_string = ( px.value.value_type == ECMA_TYPE_STRING );
  const bool is_py_string = ( py.value.value_type == ECMA_TYPE_STRING );

  if ( !( is_px_string && is_py_string ) )
    { // 3.
      // a.
      ECMA_TRY_CATCH( nx, ecma_op_to_number( px.value), ret_value);

      // b.
      ECMA_TRY_CATCH( ny, ecma_op_to_number( py.value), ret_value);

      ecma_number_t* num_x_p = (ecma_number_t*)ecma_get_pointer( nx.value.value);
      ecma_number_t* num_y_p = (ecma_number_t*)ecma_get_pointer( ny.value.value);

      TODO( /* Implement according to ECMA */ );

      if ( *num_x_p >= *num_y_p )
        {
          ret_value = ecma_make_completion_value (ECMA_COMPLETION_TYPE_NORMAL,
                                                  ecma_make_simple_value( ECMA_SIMPLE_VALUE_FALSE),
                                                  ECMA_TARGET_ID_RESERVED);
        }
      else
        {
          ret_value = ecma_make_completion_value (ECMA_COMPLETION_TYPE_NORMAL,
                                                  ecma_make_simple_value( ECMA_SIMPLE_VALUE_TRUE),
                                                  ECMA_TARGET_ID_RESERVED);
        }

      ECMA_FINALIZE( ny);
      ECMA_FINALIZE( nx);
    }
  else
    { // 4.
      JERRY_UNIMPLEMENTED();
    }

  ECMA_FINALIZE( prim_second_converted_value);
  ECMA_FINALIZE( prim_first_converted_value);

  return ret_value;
} /* ecma_op_abstract_relational_compare */

/**
 * @}
 * @}
 */