Generate builtin getters for Date object

[szledan]

The Date Prototype Object (15.9.5) has some getters (around 26), that are very similar. For now, I implemented most of them separately in [1]. Maybe we could generate them. The most different parts are in a try-catch block.
Could you give some ideas how I should generate these getter functions.

Some typically differences:

• the helper functions return value is: int or ecma_number_t
• Every getter function has a simple and an UTC version.

CC: @egavrin @ruben-ayrapetyan @galpeter @zherczeg @LaszloLango

[1] szledan@51275ff

[egavrin]

Maybe we can use the dark magic of macros?

[szledan]

That was my first idea.. :)

[ruben-ayrapetyan]

To reduce amount of source code, we could use something like in the following example.

But, in the case, very similar binary code of the functions would be repeated for each function. Maybe, this should be considered during optimization stage.

/**
 * Helper macro, converting value that would be returned
 * from a Data.prototype built-in's getter routine (ecma_number_t case)
 */
#define CONV_GETTER_RETVAL_ecma_number_t(value) (value)

/**
 * Helper macro, converting value that would be returned
 * from a Data.prototype built-in's getter routine (int32_t case)
 */
#define CONV_GETTER_RETVAL_int32_t(value) ecma_int32_to_number (value)

/**
 * Implementation of Data.prototype built-in's getter routines
 *
 * @return completion value
 *         Returned value must be freed with ecma_free_completion_value.
 */
#define DEFINE_GETTER(_ecma_paragraph, _routine_name, _getter_name, _type) \
 static ecma_completion_value_t \
 ecma_builtin_date_prototype_get_utc_minutes (ecma_value_t this_arg) /**< this argument */ \
 { \
   ecma_completion_value_t ret_value = ecma_make_empty_completion_value (); \
 \
/* 1. */ \
 ECMA_TRY_CATCH (value, ecma_builtin_date_prototype_get_time (_this_arg), _ret_value); \
 ecma_number_t *this_num = ecma_get_number_from_value (_value); \
 /* 2. */ \
 if (ecma_number_is_nan (*this_num)) \
 { \
   ecma_string_t *nan_str_p = ecma_get_magic_string (ECMA_MAGIC_STRING_NAN); \
   _ret_value = ecma_make_normal_completion_value (ecma_make_string_value (nan_str_p)); \
 } \
 else \
 { \
   /* 3. */ \
   _type utc_minutes = _getter_name (*this_num); \
   ecma_number_t *ret_num_p = ecma_alloc_number (); \
   *ret_num_p = CONV_GETTER_RETVAL ## _type (_utc_minutes); \
   _ret_value = ecma_make_normal_completion_value (ecma_make_number_value (ret_num_p)); \
 } \
 ECMA_FINALIZE (value); \
\
 return ret_value; \
}

DEFINE_GETTER (ECMA-262 v5 15.9.5.10,
               ecma_builtin_date_prototype_get_utc_minutes,
               ecma_date_min_from_time,
               ecma_number_t);
...

#undef CONV_GETTER_RETVAL_int32_t
#undef CONV_GETTER_RETVAL_ecma_number_t
#undef DEFINE_GETTER

Please, also look at similar technique in jerry-core/ecma/base/ecma-alloc.cpp.

[galpeter]

Closing issue, as this was implemented in #334 and landed in: 8d7cdeb