Support caching of next method in generators. (#3937)

JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg zherczeg.u-szeged@partner.samsung.com

jerry-core/ecma/operations/ecma-async-generator-object.c

@@ -203,7 +203,9 @@ ecma_async_generator_run (vm_executable_object_t *async_generator_object_p) /**<
     {
       case ECMA_ASYNC_GENERATOR_DO_NEXT:
       {
-        result = ecma_op_iterator_next (async_generator_object_p->frame_ctx.block_result, task_p->operation_value);
+        result = ecma_op_iterator_next (async_generator_object_p->frame_ctx.block_result,
+                                        async_generator_object_p->frame_ctx.stack_top_p[-1],
+                                        task_p->operation_value);
 
         if (ECMA_IS_VALUE_ERROR (result))
         {
@@ -256,6 +258,10 @@ ecma_async_generator_run (vm_executable_object_t *async_generator_object_p) /**<
     async_generator_object_p->frame_ctx.block_result = ECMA_VALUE_UNDEFINED;
     async_generator_object_p->frame_ctx.byte_code_p = opfunc_resume_executable_object_with_throw;
 
+    JERRY_ASSERT (async_generator_object_p->frame_ctx.stack_top_p[-1] == ECMA_VALUE_UNDEFINED
+                  || ecma_is_value_object (async_generator_object_p->frame_ctx.stack_top_p[-1]));
+    async_generator_object_p->frame_ctx.stack_top_p--;
+
     result = jcontext_take_exception ();
   }
   else

jerry-core/ecma/operations/ecma-container-object.c

@@ -439,7 +439,7 @@ ecma_op_container_create (const ecma_value_t *arguments_list_p, /**< arguments l
 
   ecma_object_t *adder_func_p = ecma_get_object_from_value (result);
 
-  result = ecma_op_get_iterator (iterable, ECMA_VALUE_SYNC_ITERATOR);
+  result = ecma_op_get_iterator (iterable, ECMA_VALUE_SYNC_ITERATOR, NULL);
 
   if (ECMA_IS_VALUE_ERROR (result))
   {

jerry-core/ecma/operations/ecma-iterator-object.c

@@ -163,7 +163,7 @@ ecma_op_create_iterator_object (ecma_value_t iterated_value, /**< value from cre
 /**
  * GetIterator operation
  *
- * See also: ECMA-262 v6, 7.4.1
+ * See also: ECMA-262 v10, 7.4.1
  *
  * Note:
  *      Returned value must be freed with ecma_free_value.
@@ -173,21 +173,28 @@ ecma_op_create_iterator_object (ecma_value_t iterated_value, /**< value from cre
  */
 ecma_value_t
 ecma_op_get_iterator (ecma_value_t value, /**< value to get iterator from */
-                      ecma_value_t method) /**< provided method argument */
+                      ecma_value_t method, /**< provided method argument */
+                      ecma_value_t *next_method_p) /**< [out] next method */
 {
+  if (next_method_p != NULL)
+  {
+    /* TODO: NULL support should be removed after all functions support next method caching. */
+    *next_method_p = ECMA_VALUE_UNDEFINED;
+  }
+
   /* 1. */
   if (ECMA_IS_VALUE_ERROR (value))
   {
     return value;
   }
 
-  bool has_method = false;
+  bool use_default_method = false;
 
   /* 2. */
   if (method == ECMA_VALUE_SYNC_ITERATOR)
   {
     /* 2.a */
-    has_method = true;
+    use_default_method = true;
     method = ecma_op_get_method_by_symbol_id (value, LIT_GLOBAL_SYMBOL_ITERATOR);
 
     /* 2.b */
@@ -199,7 +206,7 @@ ecma_op_get_iterator (ecma_value_t value, /**< value to get iterator from */
   else if (method == ECMA_VALUE_ASYNC_ITERATOR)
   {
     /* TODO: CreateAsyncFromSyncIterator should be supported. */
-    has_method = true;
+    use_default_method = true;
     method = ecma_op_get_method_by_symbol_id (value, LIT_GLOBAL_SYMBOL_ASYNC_ITERATOR);
 
     if (ECMA_IS_VALUE_ERROR (method))
@@ -212,13 +219,13 @@ ecma_op_get_iterator (ecma_value_t value, /**< value to get iterator from */
   if (!ecma_is_value_object (method) || !ecma_op_is_callable (method))
   {
     ecma_free_value (method);
-    return ecma_raise_type_error (ECMA_ERR_MSG ("object is not iterable"));
+    return ecma_raise_type_error (ECMA_ERR_MSG ("Iterator is not function"));
   }
 
   ecma_object_t *method_obj_p = ecma_get_object_from_value (method);
   ecma_value_t iterator = ecma_op_function_call (method_obj_p, value, NULL, 0);
 
-  if (has_method)
+  if (use_default_method)
   {
     ecma_deref_object (method_obj_p);
   }
@@ -236,6 +243,27 @@ ecma_op_get_iterator (ecma_value_t value, /**< value to get iterator from */
     return ecma_raise_type_error (ECMA_ERR_MSG ("Iterator is not an object."));
   }
 
+  if (next_method_p != NULL)
+  {
+    ecma_object_t *obj_p = ecma_get_object_from_value (iterator);
+    ecma_value_t next_method = ecma_op_object_get_by_magic_id (obj_p, LIT_MAGIC_STRING_NEXT);
+
+    if (ECMA_IS_VALUE_ERROR (next_method))
+    {
+      ecma_free_value (iterator);
+      return next_method;
+    }
+
+    if (ecma_is_value_object (next_method) && ecma_op_is_callable (next_method))
+    {
+      *next_method_p = next_method;
+    }
+    else
+    {
+      ecma_free_value (next_method);
+    }
+  }
+
   /* 6. */
   return iterator;
 } /* ecma_op_get_iterator */
@@ -251,9 +279,9 @@ ecma_op_get_iterator (ecma_value_t value, /**< value to get iterator from */
  * @return iterator result object - if success
  *         raised error - otherwise
  */
-ecma_value_t
-ecma_op_iterator_next (ecma_value_t iterator, /**< iterator value */
-                       ecma_value_t value) /**< the routines's value argument */
+static ecma_value_t
+ecma_op_iterator_next_old (ecma_value_t iterator, /**< iterator value */
+                           ecma_value_t value) /**< the routines's value argument */
 {
   JERRY_ASSERT (ecma_is_value_object (iterator));
 
@@ -291,6 +319,42 @@ ecma_op_iterator_next (ecma_value_t iterator, /**< iterator value */
 
   /* 5. */
   return result;
+} /* ecma_op_iterator_next_old */
+
+/**
+ * IteratorNext operation
+ *
+ * See also: ECMA-262 v10, 7.4.2
+ *
+ * Note:
+ *      Returned value must be freed with ecma_free_value.
+ *
+ * @return iterator result object - if success
+ *         raised error - otherwise
+ */
+ecma_value_t
+ecma_op_iterator_next (ecma_value_t iterator, /**< iterator value */
+                       ecma_value_t next_method, /**< next method */
+                       ecma_value_t value) /**< the routines's value argument */
+{
+  JERRY_ASSERT (ecma_is_value_object (iterator));
+
+  /* 1 - 2. */
+  if (next_method == ECMA_VALUE_UNDEFINED)
+  {
+    return ecma_raise_type_error (ECMA_ERR_MSG ("Iterator next() is not callable."));
+  }
+
+  ecma_object_t *next_method_obj_p = ecma_get_object_from_value (next_method);
+
+  bool has_value = !ecma_is_value_empty (value);
+
+  if (has_value)
+  {
+    return ecma_op_function_call (next_method_obj_p, iterator, &value, 1);
+  }
+
+  return ecma_op_function_call (next_method_obj_p, iterator, NULL, 0);
 } /* ecma_op_iterator_next */
 
 /**
@@ -518,7 +582,7 @@ ecma_value_t
 ecma_op_iterator_step (ecma_value_t iterator) /**< iterator value */
 {
   /* 1. */
-  ecma_value_t result = ecma_op_iterator_next (iterator, ECMA_VALUE_EMPTY);
+  ecma_value_t result = ecma_op_iterator_next_old (iterator, ECMA_VALUE_EMPTY);
 
   /* 2. */
   if (ECMA_IS_VALUE_ERROR (result))
@@ -569,6 +633,7 @@ ecma_op_iterator_step (ecma_value_t iterator) /**< iterator value */
 ecma_value_t
 ecma_op_iterator_do (ecma_iterator_command_type_t command, /**< command to be executed */
                      ecma_value_t iterator, /**< iterator object */
+                     ecma_value_t next_method, /**< next method */
                      ecma_value_t value, /**< the routines's value argument */
                      bool *done_p) /**< it contains the logical value of the done property */
 {
@@ -576,16 +641,16 @@ ecma_op_iterator_do (ecma_iterator_command_type_t command, /**< command to be ex
 
   if (command == ECMA_ITERATOR_NEXT)
   {
-    result = ecma_op_iterator_next (iterator, value);
+    result = ecma_op_iterator_next (iterator, next_method, value);
   }
-  else if (command == ECMA_ITERATOR_RETURN)
+  else if (command == ECMA_ITERATOR_THROW)
   {
-    result = ecma_op_iterator_return (iterator, value);
+    result = ecma_op_iterator_throw (iterator, value);
   }
   else
   {
-    JERRY_ASSERT (command == ECMA_ITERATOR_THROW);
-    result = ecma_op_iterator_throw (iterator, value);
+    JERRY_ASSERT (command == ECMA_ITERATOR_RETURN);
+    result = ecma_op_iterator_return (iterator, value);
   }
 
   if (ECMA_IS_VALUE_ERROR (result))

jerry-core/ecma/operations/ecma-iterator-object.h

@@ -33,8 +33,8 @@
 typedef enum
 {
   ECMA_ITERATOR_NEXT, /**< generator should continue its execution */
-  ECMA_ITERATOR_RETURN, /**< generator should perform a return operation */
   ECMA_ITERATOR_THROW, /**< generator should perform a throw operation */
+  ECMA_ITERATOR_RETURN, /**< generator should perform a return operation */
 } ecma_iterator_command_type_t;
 
 /**
@@ -54,13 +54,13 @@ ecma_value_t
 ecma_create_array_from_iter_element (ecma_value_t value, ecma_value_t index_value);
 
 ecma_value_t
-ecma_op_get_iterator (ecma_value_t value, ecma_value_t method);
+ecma_op_get_iterator (ecma_value_t value, ecma_value_t method, ecma_value_t *next_method_p);
 
 ecma_value_t
 ecma_op_iterator_value (ecma_value_t iter_result);
 
 ecma_value_t
-ecma_op_iterator_next (ecma_value_t iterator, ecma_value_t value);
+ecma_op_iterator_next (ecma_value_t iterator, ecma_value_t next_method, ecma_value_t value);
 
 ecma_value_t
 ecma_op_iterator_close (ecma_value_t iterator);
@@ -70,7 +70,7 @@ ecma_op_iterator_step (ecma_value_t iterator);
 
 ecma_value_t
 ecma_op_iterator_do (ecma_iterator_command_type_t command, ecma_value_t iterator,
-                     ecma_value_t value, bool *done_p);
+                     ecma_value_t next_method, ecma_value_t value, bool *done_p);
 
 #endif /* ENABLED (JERRY_ESNEXT) */
 

jerry-core/ecma/operations/ecma-jobqueue.c

@@ -277,6 +277,10 @@ ecma_process_promise_async_reaction_job (ecma_job_promise_async_reaction_t *job_
       JERRY_ASSERT (ecma_is_value_object (executable_object_p->frame_ctx.block_result));
       executable_object_p->frame_ctx.block_result = ECMA_VALUE_UNDEFINED;
       executable_object_p->frame_ctx.byte_code_p = opfunc_resume_executable_object_with_throw;
+
+      JERRY_ASSERT (executable_object_p->frame_ctx.stack_top_p[-1] == ECMA_VALUE_UNDEFINED
+                    || ecma_is_value_object (executable_object_p->frame_ctx.stack_top_p[-1]));
+      executable_object_p->frame_ctx.stack_top_p--;
     }
   }
 
@@ -303,6 +307,10 @@ ecma_process_promise_async_reaction_job (ecma_job_promise_async_reaction_t *job_
 
     JERRY_ASSERT (ecma_is_value_object (executable_object_p->frame_ctx.block_result));
     executable_object_p->frame_ctx.block_result = ECMA_VALUE_UNDEFINED;
+
+    JERRY_ASSERT (executable_object_p->frame_ctx.stack_top_p[-1] == ECMA_VALUE_UNDEFINED
+                  || ecma_is_value_object (executable_object_p->frame_ctx.stack_top_p[-1]));
+    executable_object_p->frame_ctx.stack_top_p--;
   }
 
   ecma_value_t result = opfunc_resume_executable_object (executable_object_p, job_p->argument);

jerry-core/ecma/operations/ecma-typedarray-object.c

@@ -777,7 +777,7 @@ ecma_op_typedarray_from (ecma_value_t items_val, /**< the source array-like obje
   if (!ecma_is_value_undefined (using_iterator))
   {
     /* 8.a */
-    ecma_value_t iterator = ecma_op_get_iterator (items_val, using_iterator);
+    ecma_value_t iterator = ecma_op_get_iterator (items_val, using_iterator, NULL);
     ecma_free_value (using_iterator);
 
     /* 8.b */