Remove ECMA_LEXICAL_ENVIRONMENT_OBJECT_BOUND. (#2408)

Only the global object bound to the root node of the lexical environment
tree does not have a provideThis flag, and ecma_op_implicit_this_value()
falls back to the global object. Hence we get the same effect regardless
of provideThis.

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

6 files changed, 20 insertions, 69 deletions

diff --git a/jerry-core/ecma/base/ecma-globals.h b/jerry-core/ecma/base/ecma-globals.h
index 75d2a3e4..8194742e 100644
--- a/jerry-core/ecma/base/ecma-globals.h
+++ b/jerry-core/ecma/base/ecma-globals.h
@@ -613,9 +613,8 @@ typedef enum
   /* Types between 0 - 12 are ecma_object_type_t which can have a built-in flag. */
 
   ECMA_LEXICAL_ENVIRONMENT_DECLARATIVE = 13, /**< declarative lexical environment */
-  ECMA_LEXICAL_ENVIRONMENT_OBJECT_BOUND = 14, /**< object-bound lexical environment */
-  ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND = 15, /**< object-bound lexical environment
-                                                   *   with provideThis flag */
+  ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND = 14, /**< object-bound lexical environment
+                                                    *   with provideThis flag */
 
   ECMA_LEXICAL_ENVIRONMENT_TYPE_START = ECMA_LEXICAL_ENVIRONMENT_DECLARATIVE, /**< first lexical
                                                                                *    environment type */
diff --git a/jerry-core/ecma/base/ecma-helpers.c b/jerry-core/ecma/base/ecma-helpers.c
index 275c5496..0f10e7d8 100644
--- a/jerry-core/ecma/base/ecma-helpers.c
+++ b/jerry-core/ecma/base/ecma-helpers.c
@@ -140,24 +140,14 @@ ecma_create_decl_lex_env (ecma_object_t *outer_lexical_environment_p) /**< outer
  */
 ecma_object_t *
 ecma_create_object_lex_env (ecma_object_t *outer_lexical_environment_p, /**< outer lexical environment */
-                            ecma_object_t *binding_obj_p, /**< binding object */
-                            bool provide_this) /**< provideThis flag */
+                            ecma_object_t *binding_obj_p) /**< binding object */
 {
   JERRY_ASSERT (binding_obj_p != NULL
                 && !ecma_is_lexical_environment (binding_obj_p));
 
   ecma_object_t *new_lexical_environment_p = ecma_alloc_object ();
 
-  uint16_t type;
-
-  if (provide_this)
-  {
-    type = ECMA_OBJECT_FLAG_BUILT_IN_OR_LEXICAL_ENV | ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND;
-  }
-  else
-  {
-    type = ECMA_OBJECT_FLAG_BUILT_IN_OR_LEXICAL_ENV | ECMA_LEXICAL_ENVIRONMENT_OBJECT_BOUND;
-  }
+  uint16_t type = ECMA_OBJECT_FLAG_BUILT_IN_OR_LEXICAL_ENV | ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND;
 
   new_lexical_environment_p->type_flags_refs = type;
 
@@ -359,23 +349,6 @@ ecma_get_property_list (const ecma_object_t *object_p) /**< object or lexical en
 } /* ecma_get_property_list */
 
 /**
- * Get lexical environment's 'provideThis' property
- *
- * @return true  - if it has 'this' property
- *         false - otherwise
- */
-inline bool JERRY_ATTR_PURE
-ecma_get_lex_env_provide_this (const ecma_object_t *object_p) /**< object-bound lexical environment */
-{
-  JERRY_ASSERT (object_p != NULL);
-  JERRY_ASSERT (ecma_is_lexical_environment (object_p));
-  JERRY_ASSERT (ecma_get_lex_env_type (object_p) == ECMA_LEXICAL_ENVIRONMENT_OBJECT_BOUND
-                || ecma_get_lex_env_type (object_p) == ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND);
-
-  return ecma_get_lex_env_type (object_p) == ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND;
-} /* ecma_get_lex_env_provide_this */
-
-/**
  * Get lexical environment's bound object.
  *
  * @return pointer to ecma object
@@ -385,8 +358,7 @@ ecma_get_lex_env_binding_object (const ecma_object_t *object_p) /**< object-boun
 {
   JERRY_ASSERT (object_p != NULL);
   JERRY_ASSERT (ecma_is_lexical_environment (object_p));
-  JERRY_ASSERT (ecma_get_lex_env_type (object_p) == ECMA_LEXICAL_ENVIRONMENT_OBJECT_BOUND
-                || ecma_get_lex_env_type (object_p) == ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND);
+  JERRY_ASSERT (ecma_get_lex_env_type (object_p) == ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND);
 
   return ECMA_GET_NON_NULL_POINTER (ecma_object_t,
                                     object_p->property_list_or_bound_object_cp);
diff --git a/jerry-core/ecma/base/ecma-helpers.h b/jerry-core/ecma/base/ecma-helpers.h
index 16a12456..7476d377 100644
--- a/jerry-core/ecma/base/ecma-helpers.h
+++ b/jerry-core/ecma/base/ecma-helpers.h
@@ -297,8 +297,7 @@ ecma_collection_iterator_next (ecma_value_t *iterator_p);
 /* ecma-helpers.c */
 ecma_object_t *ecma_create_object (ecma_object_t *prototype_object_p, size_t ext_object_size, ecma_object_type_t type);
 ecma_object_t *ecma_create_decl_lex_env (ecma_object_t *outer_lexical_environment_p);
-ecma_object_t *ecma_create_object_lex_env (ecma_object_t *outer_lexical_environment_p, ecma_object_t *binding_obj_p,
-                                           bool provide_this);
+ecma_object_t *ecma_create_object_lex_env (ecma_object_t *outer_lexical_environment_p, ecma_object_t *binding_obj_p);
 bool JERRY_ATTR_PURE ecma_is_lexical_environment (const ecma_object_t *object_p);
 bool JERRY_ATTR_PURE ecma_get_object_extensible (const ecma_object_t *object_p);
 void ecma_set_object_extensible (ecma_object_t *object_p, bool is_extensible);
@@ -311,7 +310,6 @@ ecma_lexical_environment_type_t JERRY_ATTR_PURE ecma_get_lex_env_type (const ecm
 ecma_object_t JERRY_ATTR_PURE *ecma_get_lex_env_outer_reference (const ecma_object_t *object_p);
 ecma_property_header_t JERRY_ATTR_PURE *ecma_get_property_list (const ecma_object_t *object_p);
 ecma_object_t JERRY_ATTR_PURE *ecma_get_lex_env_binding_object (const ecma_object_t *object_p);
-bool JERRY_ATTR_PURE ecma_get_lex_env_provide_this (const ecma_object_t *object_p);
 
 ecma_property_value_t *
 ecma_create_named_data_property (ecma_object_t *object_p, ecma_string_t *name_p, uint8_t prop_attributes,
diff --git a/jerry-core/ecma/operations/ecma-lex-env.c b/jerry-core/ecma/operations/ecma-lex-env.c
index b9438578..758055bd 100644
--- a/jerry-core/ecma/operations/ecma-lex-env.c
+++ b/jerry-core/ecma/operations/ecma-lex-env.c
@@ -41,7 +41,7 @@ ecma_init_global_lex_env (void)
 {
   ecma_object_t *glob_obj_p = ecma_builtin_get (ECMA_BUILTIN_ID_GLOBAL);
 
-  JERRY_CONTEXT (ecma_global_lex_env_p) = ecma_create_object_lex_env (NULL, glob_obj_p, false);
+  JERRY_CONTEXT (ecma_global_lex_env_p) = ecma_create_object_lex_env (NULL, glob_obj_p);
 
   ecma_deref_object (glob_obj_p);
 } /* ecma_init_global_lex_env */
@@ -94,8 +94,7 @@ ecma_op_has_binding (ecma_object_t *lex_env_p, /**< lexical environment */
   }
   else
   {
-    JERRY_ASSERT (ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_OBJECT_BOUND
-                  || ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND);
+    JERRY_ASSERT (ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND);
 
     ecma_object_t *binding_obj_p = ecma_get_lex_env_binding_object (lex_env_p);
 
@@ -136,8 +135,7 @@ ecma_op_create_mutable_binding (ecma_object_t *lex_env_p, /**< lexical environme
   }
   else
   {
-    JERRY_ASSERT (ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_OBJECT_BOUND
-                  || ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND);
+    JERRY_ASSERT (ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND);
 
     ecma_object_t *binding_obj_p = ecma_get_lex_env_binding_object (lex_env_p);
 
@@ -204,8 +202,7 @@ ecma_op_set_mutable_binding (ecma_object_t *lex_env_p, /**< lexical environment
   }
   else
   {
-    JERRY_ASSERT (ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_OBJECT_BOUND
-                  || ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND);
+    JERRY_ASSERT (ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND);
 
     ecma_object_t *binding_obj_p = ecma_get_lex_env_binding_object (lex_env_p);
 
@@ -218,10 +215,8 @@ ecma_op_set_mutable_binding (ecma_object_t *lex_env_p, /**< lexical environment
     {
       return completion;
     }
-    else
-    {
-      JERRY_ASSERT (ecma_is_value_boolean (completion));
-    }
+
+    JERRY_ASSERT (ecma_is_value_boolean (completion));
   }
 
   return ECMA_VALUE_EMPTY;
@@ -252,8 +247,7 @@ ecma_op_get_binding_value (ecma_object_t *lex_env_p, /**< lexical environment */
   }
   else
   {
-    JERRY_ASSERT (ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_OBJECT_BOUND
-                  || ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND);
+    JERRY_ASSERT (ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND);
 
     ecma_object_t *binding_obj_p = ecma_get_lex_env_binding_object (lex_env_p);
 
@@ -322,8 +316,7 @@ ecma_op_delete_binding (ecma_object_t *lex_env_p, /**< lexical environment */
   }
   else
   {
-    JERRY_ASSERT (ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_OBJECT_BOUND
-                  || ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND);
+    JERRY_ASSERT (ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND);
 
     ecma_object_t *binding_obj_p = ecma_get_lex_env_binding_object (lex_env_p);
 
@@ -351,20 +344,12 @@ ecma_op_implicit_this_value (ecma_object_t *lex_env_p) /**< lexical environment
   }
   else
   {
-    JERRY_ASSERT (ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_OBJECT_BOUND
-                  || ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND);
+    JERRY_ASSERT (ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND);
 
-    if (ecma_get_lex_env_provide_this (lex_env_p))
-    {
-      ecma_object_t *binding_obj_p = ecma_get_lex_env_binding_object (lex_env_p);
-      ecma_ref_object (binding_obj_p);
+    ecma_object_t *binding_obj_p = ecma_get_lex_env_binding_object (lex_env_p);
+    ecma_ref_object (binding_obj_p);
 
-      return ecma_make_object_value (binding_obj_p);
-    }
-    else
-    {
-      return ECMA_VALUE_UNDEFINED;
-    }
+    return ecma_make_object_value (binding_obj_p);
   }
 } /* ecma_op_implicit_this_value */
 
diff --git a/jerry-core/ecma/operations/ecma-reference.c b/jerry-core/ecma/operations/ecma-reference.c
index b64070e2..961e3c85 100644
--- a/jerry-core/ecma/operations/ecma-reference.c
+++ b/jerry-core/ecma/operations/ecma-reference.c
@@ -83,8 +83,7 @@ ecma_op_resolve_reference_value (ecma_object_t *lex_env_p, /**< starting lexical
     }
     else
     {
-      JERRY_ASSERT (ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_OBJECT_BOUND
-                    || ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND);
+      JERRY_ASSERT (ecma_get_lex_env_type (lex_env_p) == ECMA_LEXICAL_ENVIRONMENT_THIS_OBJECT_BOUND);
 
       ecma_object_t *binding_obj_p = ecma_get_lex_env_binding_object (lex_env_p);
 
diff --git a/jerry-core/vm/vm.c b/jerry-core/vm/vm.c
index 32aae2e3..5c62d087 100644
--- a/jerry-core/vm/vm.c
+++ b/jerry-core/vm/vm.c
@@ -2300,9 +2300,7 @@ vm_loop (vm_frame_ctx_t *frame_ctx_p) /**< frame context */
 
           object_p = ecma_get_object_from_value (result);
 
-          with_env_p = ecma_create_object_lex_env (frame_ctx_p->lex_env_p,
-                                                   object_p,
-                                                   true);
+          with_env_p = ecma_create_object_lex_env (frame_ctx_p->lex_env_p, object_p);
 
           ecma_deref_object (object_p);