Implement the core of let/const statement. (#3239)

This patch implements the core part of let/const statements. Redeclarations are correctly detected and separate contexts are correctly created for these statements. Register optimizations are also emplyed whenever possible. Lots of features are still missing: - checking the var statements in eval - const are treated as lets - single statement checks are missing - export declarations are exported as vars, let/const export is not supported JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg zherczeg.u-szeged@partner.samsung.com
2019-10-25 18:08:10 +02:00
parent 4b352758c1
commit 3d797b8836
33 changed files with 1997 additions and 217 deletions
@@ -57,12 +57,18 @@ typedef enum
 {
  PARSER_STATEMENT_START,
  PARSER_STATEMENT_BLOCK,
+#if ENABLED (JERRY_ES2015)
+  PARSER_STATEMENT_BLOCK_CONTEXT,
+#endif /* ENABLED (JERRY_ES2015) */
  PARSER_STATEMENT_LABEL,
  PARSER_STATEMENT_IF,
  PARSER_STATEMENT_ELSE,
  /* From switch -> for-in : break target statements */
  PARSER_STATEMENT_SWITCH,
  PARSER_STATEMENT_SWITCH_NO_DEFAULT,
+#if ENABLED (JERRY_ES2015)
+  PARSER_STATEMENT_SWITCH_BLOCK_CONTEXT,
+#endif /* ENABLED (JERRY_ES2015) */
  /* From do-while -> for->in : continue target statements */
  PARSER_STATEMENT_DO_WHILE,
  PARSER_STATEMENT_WHILE,
@@ -78,6 +84,40 @@ typedef enum
  PARSER_STATEMENT_TRY,
 } parser_statement_type_t;

+#if !ENABLED (JERRY_ES2015)
+
+/**
+ * Get the expected depth of a function call.
+ */
+#define JERRY_GET_EXPECTED_DEPTH(context_p) 0
+
+#else /* ENABLED (JERRY_ES2015) */
+
+/**
+ * Get the expected depth of a function call.
+ */
+#define JERRY_GET_EXPECTED_DEPTH(context_p) \
+  (((context_p)->status_flags & PARSER_INSIDE_BLOCK) ? PARSER_BLOCK_CONTEXT_STACK_ALLOCATION : 0)
+
+/**
+ * Block statement.
+ */
+typedef struct
+{
+  uint16_t scope_stack_top;               /**< preserved top of scope stack */
+  uint16_t scope_stack_reg_top;           /**< preserved top register of scope stack */
+} parser_block_statement_t;
+
+/**
+ * Context of block statement.
+ */
+typedef struct
+{
+  parser_branch_t branch;                 /**< branch to the end */
+} parser_block_context_t;
+
+#endif /* !ENABLED (JERRY_ES2015) */
+
 /**
 * Loop statement.
 */
@@ -110,6 +150,10 @@ typedef struct
 {
  parser_branch_t default_branch;         /**< branch to the default case */
  parser_branch_node_t *branch_list_p;    /**< branches of case statements */
+#if ENABLED (JERRY_ES2015)
+  uint16_t scope_stack_top;               /**< preserved top of scope stack */
+  uint16_t scope_stack_reg_top;           /**< preserved top register of scope stack */
+#endif /* ENABLED (JERRY_ES2015) */
 } parser_switch_statement_t;

 /**
@@ -190,8 +234,15 @@ parser_statement_length (uint8_t type) /**< type of statement */
 {
  static const uint8_t statement_lengths[] =
  {
+#if ENABLED (JERRY_ES2015)
+    /* PARSER_STATEMENT_BLOCK */
+    (uint8_t) (sizeof (parser_block_statement_t) + 1),
+    /* PARSER_STATEMENT_BLOCK_CONTEXT */
+    (uint8_t) (sizeof (parser_block_statement_t) + sizeof (parser_block_context_t) + 1),
+#else /* !ENABLED (JERRY_ES2015) */
    /* PARSER_STATEMENT_BLOCK */
    1,
+#endif /* ENABLED (JERRY_ES2015) */
    /* PARSER_STATEMENT_LABEL */
    (uint8_t) (sizeof (parser_label_statement_t) + 1),
    /* PARSER_STATEMENT_IF */
@@ -202,6 +253,10 @@ parser_statement_length (uint8_t type) /**< type of statement */
    (uint8_t) (sizeof (parser_switch_statement_t) + sizeof (parser_loop_statement_t) + 1),
    /* PARSER_STATEMENT_SWITCH_NO_DEFAULT */
    (uint8_t) (sizeof (parser_switch_statement_t) + sizeof (parser_loop_statement_t) + 1),
+#if ENABLED (JERRY_ES2015)
+    /* PARSER_STATEMENT_SWITCH_BLOCK_CONTEXT */
+    (uint8_t) (sizeof (parser_block_context_t) + 1),
+#endif /* ENABLED (JERRY_ES2015) */
    /* PARSER_STATEMENT_DO_WHILE */
    (uint8_t) (sizeof (parser_do_while_statement_t) + sizeof (parser_loop_statement_t) + 1),
    /* PARSER_STATEMENT_WHILE */
@@ -293,7 +348,9 @@ parser_parse_enclosed_expr (parser_context_t *context_p) /**< context */
 static void
 parser_parse_var_statement (parser_context_t *context_p) /**< context */
 {
-  JERRY_ASSERT (context_p->token.type == LEXER_KEYW_VAR);
+  JERRY_ASSERT (context_p->token.type == LEXER_KEYW_VAR
+                || context_p->token.type == LEXER_KEYW_LET
+                || context_p->token.type == LEXER_KEYW_CONST);

  while (true)
  {
@@ -313,6 +370,14 @@ parser_parse_var_statement (parser_context_t *context_p) /**< context */
    }
 #endif /* ENABLED (JERRY_ES2015_MODULE_SYSTEM) */

+#if ENABLED (JERRY_ES2015)
+    if (context_p->next_scanner_info_p->source_p == context_p->source_p)
+    {
+      JERRY_ASSERT (context_p->next_scanner_info_p->type == SCANNER_TYPE_ERR_REDECLARED);
+      parser_raise_error (context_p, PARSER_ERR_VARIABLE_REDECLARED);
+    }
+#endif /* ENABLED (JERRY_ES2015) */
+
    lexer_next_token (context_p);

    if (context_p->token.type == LEXER_ASSIGN)
@@ -368,6 +433,14 @@ parser_parse_function_statement (parser_context_t *context_p) /**< context */
  JERRY_ASSERT (context_p->token.type == LEXER_LITERAL
                && context_p->token.lit_location.type == LEXER_IDENT_LITERAL);

+#if ENABLED (JERRY_ES2015)
+  if (context_p->next_scanner_info_p->source_p == context_p->source_p)
+  {
+    JERRY_ASSERT (context_p->next_scanner_info_p->type == SCANNER_TYPE_ERR_REDECLARED);
+    parser_raise_error (context_p, PARSER_ERR_VARIABLE_REDECLARED);
+  }
+#endif /* ENABLED (JERRY_ES2015) */
+
  if (context_p->lit_object.type == LEXER_LITERAL_OBJECT_ARGUMENTS)
  {
    context_p->status_flags |= PARSER_ARGUMENTS_NOT_NEEDED;
@@ -1185,6 +1258,33 @@ parser_parse_switch_statement_start (parser_context_t *context_p) /**< context *
    parser_raise_error (context_p, PARSER_ERR_LEFT_BRACE_EXPECTED);
  }

+#if ENABLED (JERRY_ES2015)
+  switch_statement.scope_stack_top = context_p->scope_stack_top;
+  switch_statement.scope_stack_reg_top = context_p->scope_stack_reg_top;
+
+  if (context_p->next_scanner_info_p->source_p == context_p->source_p - 1)
+  {
+    JERRY_ASSERT (context_p->next_scanner_info_p->type == SCANNER_TYPE_BLOCK);
+
+    if (scanner_is_context_needed (context_p))
+    {
+      parser_block_context_t block_context;
+
+#ifndef JERRY_NDEBUG
+      PARSER_PLUS_EQUAL_U16 (context_p->context_stack_depth, PARSER_BLOCK_CONTEXT_STACK_ALLOCATION);
+#endif /* !JERRY_NDEBUG */
+
+      parser_emit_cbc_forward_branch (context_p,
+                                      CBC_BLOCK_CREATE_CONTEXT,
+                                      &block_context.branch);
+      parser_stack_push (context_p, &block_context, sizeof (parser_block_context_t));
+      parser_stack_push_uint8 (context_p, PARSER_STATEMENT_SWITCH_BLOCK_CONTEXT);
+    }
+
+    scanner_create_variables (context_p, sizeof (scanner_info_t));
+  }
+#endif /* ENABLED (JERRY_ES2015) */
+
  JERRY_ASSERT (context_p->next_scanner_info_p->source_p == context_p->source_p
                && context_p->next_scanner_info_p->type == SCANNER_TYPE_SWITCH);

@@ -1201,6 +1301,14 @@ parser_parse_switch_statement_start (parser_context_t *context_p) /**< context *

      parser_emit_cbc (context_p, CBC_POP);
      parser_flush_cbc (context_p);
+
+#if ENABLED (JERRY_ES2015)
+      parser_block_statement_t block_statement;
+      block_statement.scope_stack_top = context_p->scope_stack_top;
+      block_statement.scope_stack_reg_top = context_p->scope_stack_reg_top;
+      parser_stack_push (context_p, &block_statement, sizeof (parser_block_statement_t));
+#endif /* ENABLED (JERRY_ES2015) */
+
      parser_stack_push_uint8 (context_p, PARSER_STATEMENT_BLOCK);
      parser_stack_iterator_init (context_p, &context_p->last_statement);
      return;
@@ -1349,6 +1457,11 @@ parser_parse_try_statement_end (parser_context_t *context_p) /**< context */
  parser_stack_iterator_skip (&iterator, 1);
  parser_stack_iterator_read (&iterator, &try_statement, sizeof (parser_try_statement_t));

+#if ENABLED (JERRY_ES2015)
+  context_p->scope_stack_top = try_statement.scope_stack_top;
+  context_p->scope_stack_reg_top = try_statement.scope_stack_reg_top;
+#endif /* ENABLED (JERRY_ES2015) */
+
  lexer_next_token (context_p);

  if (try_statement.type == parser_finally_block)
@@ -1368,8 +1481,10 @@ parser_parse_try_statement_end (parser_context_t *context_p) /**< context */

    if (try_statement.type == parser_catch_block)
    {
+#if !ENABLED (JERRY_ES2015)
      context_p->scope_stack_top = try_statement.scope_stack_top;
      context_p->scope_stack_reg_top = try_statement.scope_stack_reg_top;
+#endif /* !ENABLED (JERRY_ES2015) */

      if (context_p->token.type != LEXER_KEYW_FINALLY)
      {
@@ -1423,12 +1538,18 @@ parser_parse_try_statement_end (parser_context_t *context_p) /**< context */
    bool block_found = false;
 #endif /* !JERRY_NDEBUG */

-    if (context_p->next_scanner_info_p->source_p == context_p->source_p
-        && context_p->next_scanner_info_p->type == SCANNER_TYPE_BLOCK)
+    if (context_p->next_scanner_info_p->source_p == context_p->source_p)
    {
+      JERRY_ASSERT (context_p->next_scanner_info_p->type == SCANNER_TYPE_BLOCK);
 #ifndef JERRY_NDEBUG
      block_found = true;
 #endif /* !JERRY_NDEBUG */
+
+      if (scanner_is_context_needed (context_p))
+      {
+        parser_emit_cbc_ext (context_p, CBC_EXT_TRY_CREATE_ENV);
+      }
+
      scanner_create_variables (context_p, sizeof (scanner_info_t));
    }

@@ -1474,6 +1595,20 @@ parser_parse_try_statement_end (parser_context_t *context_p) /**< context */
    parser_emit_cbc_ext_forward_branch (context_p,
                                        CBC_EXT_FINALLY,
                                        &try_statement.branch);
+
+#if ENABLED (JERRY_ES2015)
+    if (context_p->next_scanner_info_p->source_p == context_p->source_p)
+    {
+      JERRY_ASSERT (context_p->next_scanner_info_p->type == SCANNER_TYPE_BLOCK);
+
+      if (scanner_is_context_needed (context_p))
+      {
+        parser_emit_cbc_ext (context_p, CBC_EXT_TRY_CREATE_ENV);
+      }
+
+      scanner_create_variables (context_p, sizeof (scanner_info_t));
+    }
+#endif /* ENABLED (JERRY_ES2015) */
  }

  lexer_next_token (context_p);
@@ -1585,6 +1720,9 @@ parser_parse_break_statement (parser_context_t *context_p) /**< context */
          || type == PARSER_STATEMENT_FOR_OF
 #endif /* ENABLED (JERRY_ES2015) */
          || type == PARSER_STATEMENT_WITH
+#if ENABLED (JERRY_ES2015)
+          || type == PARSER_STATEMENT_BLOCK_CONTEXT
+#endif /* ENABLED (JERRY_ES2015) */
          || type == PARSER_STATEMENT_TRY)
      {
        opcode = CBC_JUMP_FORWARD_EXIT_CONTEXT;
@@ -1629,6 +1767,9 @@ parser_parse_break_statement (parser_context_t *context_p) /**< context */
        || type == PARSER_STATEMENT_FOR_OF
 #endif /* ENABLED (JERRY_ES2015) */
        || type == PARSER_STATEMENT_WITH
+#if ENABLED (JERRY_ES2015)
+        || type == PARSER_STATEMENT_BLOCK_CONTEXT
+#endif /* ENABLED (JERRY_ES2015) */
        || type == PARSER_STATEMENT_TRY)
    {
      opcode = CBC_JUMP_FORWARD_EXIT_CONTEXT;
@@ -1723,6 +1864,9 @@ parser_parse_continue_statement (parser_context_t *context_p) /**< context */
 #endif /* ENABLED (JERRY_ES2015) */

      if (type == PARSER_STATEMENT_WITH
+#if ENABLED (JERRY_ES2015)
+          || type == PARSER_STATEMENT_BLOCK_CONTEXT
+#endif /* ENABLED (JERRY_ES2015) */
          || type == PARSER_STATEMENT_TRY
          || for_in_of_was_seen)
      {
@@ -1782,6 +1926,9 @@ parser_parse_continue_statement (parser_context_t *context_p) /**< context */
    }

    if (type == PARSER_STATEMENT_WITH
+#if ENABLED (JERRY_ES2015)
+        || type == PARSER_STATEMENT_BLOCK_CONTEXT
+#endif /* ENABLED (JERRY_ES2015) */
        || type == PARSER_STATEMENT_TRY)
    {
      opcode = CBC_JUMP_FORWARD_EXIT_CONTEXT;
@@ -1993,6 +2140,10 @@ parser_parse_export_statement (parser_context_t *context_p) /**< context */
      break;
    }
    case LEXER_KEYW_VAR:
+#if ENABLED (JERRY_ES2015)
+    case LEXER_KEYW_LET:
+    case LEXER_KEYW_CONST:
+#endif /* ENABLED (JERRY_ES2015) */
    {
      context_p->status_flags |= PARSER_MODULE_STORE_IDENT;
      parser_parse_var_statement (context_p);
@@ -2151,7 +2302,10 @@ parser_parse_statements (parser_context_t *context_p) /**< context */
    lexer_lit_location_t lit_location;
    uint32_t status_flags = context_p->status_flags;

-    JERRY_ASSERT (context_p->stack_depth == 0);
+    JERRY_ASSERT (context_p->stack_depth == JERRY_GET_EXPECTED_DEPTH (context_p));
+#ifndef JERRY_NDEBUG
+    JERRY_ASSERT (context_p->context_stack_depth == context_p->stack_depth);
+#endif /* !JERRY_NDEBUG */

    lit_location = context_p->token.lit_location;

@@ -2246,6 +2400,8 @@ parser_parse_statements (parser_context_t *context_p) /**< context */
        && context_p->token.type != LEXER_LEFT_BRACE
        && context_p->token.type != LEXER_RIGHT_BRACE
        && context_p->token.type != LEXER_KEYW_VAR
+        && context_p->token.type != LEXER_KEYW_LET
+        && context_p->token.type != LEXER_KEYW_CONST
        && context_p->token.type != LEXER_KEYW_FUNCTION
        && context_p->token.type != LEXER_KEYW_CASE
        && context_p->token.type != LEXER_KEYW_DEFAULT)
@@ -2265,6 +2421,8 @@ parser_parse_statements (parser_context_t *context_p) /**< context */
        && context_p->token.type != LEXER_LEFT_BRACE
        && context_p->token.type != LEXER_RIGHT_BRACE
        && context_p->token.type != LEXER_KEYW_VAR
+        && context_p->token.type != LEXER_KEYW_LET
+        && context_p->token.type != LEXER_KEYW_CONST
        && context_p->token.type != LEXER_KEYW_FUNCTION
        && context_p->token.type != LEXER_KEYW_CASE
        && context_p->token.type != LEXER_KEYW_DEFAULT)
@@ -2301,13 +2459,49 @@ parser_parse_statements (parser_context_t *context_p) /**< context */

      case LEXER_LEFT_BRACE:
      {
-        parser_stack_push_uint8 (context_p, PARSER_STATEMENT_BLOCK);
+        uint8_t block_type = PARSER_STATEMENT_BLOCK;
+
+#if ENABLED (JERRY_ES2015)
+        parser_block_statement_t block_statement;
+        block_statement.scope_stack_top = context_p->scope_stack_top;
+        block_statement.scope_stack_reg_top = context_p->scope_stack_reg_top;
+
+        if (context_p->next_scanner_info_p->source_p == context_p->source_p)
+        {
+          JERRY_ASSERT (context_p->next_scanner_info_p->type == SCANNER_TYPE_BLOCK);
+
+          if (scanner_is_context_needed (context_p))
+          {
+            parser_block_context_t block_context;
+
+#ifndef JERRY_NDEBUG
+            PARSER_PLUS_EQUAL_U16 (context_p->context_stack_depth, PARSER_BLOCK_CONTEXT_STACK_ALLOCATION);
+#endif /* !JERRY_NDEBUG */
+
+            parser_emit_cbc_forward_branch (context_p,
+                                            CBC_BLOCK_CREATE_CONTEXT,
+                                            &block_context.branch);
+            parser_stack_push (context_p, &block_context, sizeof (parser_block_context_t));
+            block_type = PARSER_STATEMENT_BLOCK_CONTEXT;
+          }
+
+          scanner_create_variables (context_p, sizeof (scanner_info_t));
+        }
+
+        parser_stack_push (context_p, &block_statement, sizeof (parser_block_statement_t));
+#endif /* ENABLED (JERRY_ES2015) */
+
+        parser_stack_push_uint8 (context_p, block_type);
        parser_stack_iterator_init (context_p, &context_p->last_statement);
        lexer_next_token (context_p);
        continue;
      }

      case LEXER_KEYW_VAR:
+#if ENABLED (JERRY_ES2015)
+      case LEXER_KEYW_LET:
+      case LEXER_KEYW_CONST:
+#endif /* ENABLED (JERRY_ES2015) */
      {
        parser_parse_var_statement (context_p);
        break;
@@ -2409,6 +2603,23 @@ parser_parse_statements (parser_context_t *context_p) /**< context */
                                            CBC_EXT_TRY_CREATE_CONTEXT,
                                            &try_statement.branch);

+#if ENABLED (JERRY_ES2015)
+        try_statement.scope_stack_top = context_p->scope_stack_top;
+        try_statement.scope_stack_reg_top = context_p->scope_stack_reg_top;
+
+        if (context_p->next_scanner_info_p->source_p == context_p->source_p)
+        {
+          JERRY_ASSERT (context_p->next_scanner_info_p->type == SCANNER_TYPE_BLOCK);
+
+          if (scanner_is_context_needed (context_p))
+          {
+            parser_emit_cbc_ext (context_p, CBC_EXT_TRY_CREATE_ENV);
+          }
+
+          scanner_create_variables (context_p, sizeof (scanner_info_t));
+        }
+#endif /* ENABLED (JERRY_ES2015) */
+
        parser_stack_push (context_p, &try_statement, sizeof (parser_try_statement_t));
        parser_stack_push_uint8 (context_p, PARSER_STATEMENT_TRY);
        parser_stack_iterator_init (context_p, &context_p->last_statement);
@@ -2575,9 +2786,43 @@ parser_parse_statements (parser_context_t *context_p) /**< context */
      if (context_p->stack_top_uint8 == PARSER_STATEMENT_BLOCK)
      {
        parser_stack_pop_uint8 (context_p);
+
+#if ENABLED (JERRY_ES2015)
+        parser_block_statement_t block_statement;
+
+        parser_stack_pop (context_p, &block_statement, sizeof (parser_block_statement_t));
+        context_p->scope_stack_top = block_statement.scope_stack_top;
+        context_p->scope_stack_reg_top = block_statement.scope_stack_reg_top;
+#endif /* ENABLED (JERRY_ES2015) */
+
        parser_stack_iterator_init (context_p, &context_p->last_statement);
        lexer_next_token (context_p);
      }
+#if ENABLED (JERRY_ES2015)
+      else if (context_p->stack_top_uint8 == PARSER_STATEMENT_BLOCK_CONTEXT)
+      {
+        parser_block_statement_t block_statement;
+        parser_block_context_t block_context;
+
+        parser_stack_pop_uint8 (context_p);
+        parser_stack_pop (context_p, &block_statement, sizeof (parser_block_statement_t));
+        parser_stack_pop (context_p, &block_context, sizeof (parser_block_context_t));
+
+        context_p->scope_stack_top = block_statement.scope_stack_top;
+        context_p->scope_stack_reg_top = block_statement.scope_stack_reg_top;
+
+        PARSER_MINUS_EQUAL_U16 (context_p->stack_depth, PARSER_BLOCK_CONTEXT_STACK_ALLOCATION);
+#ifndef JERRY_NDEBUG
+        PARSER_MINUS_EQUAL_U16 (context_p->context_stack_depth, PARSER_BLOCK_CONTEXT_STACK_ALLOCATION);
+#endif /* !JERRY_NDEBUG */
+
+        parser_emit_cbc (context_p, CBC_CONTEXT_END);
+        parser_set_branch_to_current_position (context_p, &block_context.branch);
+
+        parser_stack_iterator_init (context_p, &context_p->last_statement);
+        lexer_next_token (context_p);
+      }
+#endif /* ENABLED (JERRY_ES2015) */
      else if (context_p->stack_top_uint8 == PARSER_STATEMENT_SWITCH
               || context_p->stack_top_uint8 == PARSER_STATEMENT_SWITCH_NO_DEFAULT)
      {
@@ -2590,6 +2835,11 @@ parser_parse_statements (parser_context_t *context_p) /**< context */
        parser_stack_pop (context_p, &switch_statement, sizeof (parser_switch_statement_t));
        parser_stack_iterator_init (context_p, &context_p->last_statement);

+#if ENABLED (JERRY_ES2015)
+        context_p->scope_stack_top = switch_statement.scope_stack_top;
+        context_p->scope_stack_reg_top = switch_statement.scope_stack_reg_top;
+#endif /* ENABLED (JERRY_ES2015) */
+
        JERRY_ASSERT (switch_statement.branch_list_p == NULL);

        if (!has_default)
@@ -2599,6 +2849,26 @@ parser_parse_statements (parser_context_t *context_p) /**< context */

        parser_set_breaks_to_current_position (context_p, loop.branch_list_p);
        lexer_next_token (context_p);
+
+#if ENABLED (JERRY_ES2015)
+        if (context_p->stack_top_uint8 == PARSER_STATEMENT_SWITCH_BLOCK_CONTEXT)
+        {
+          parser_block_context_t block_context;
+
+          parser_stack_pop_uint8 (context_p);
+          parser_stack_pop (context_p, &block_context, sizeof (parser_block_context_t));
+
+          PARSER_MINUS_EQUAL_U16 (context_p->stack_depth, PARSER_BLOCK_CONTEXT_STACK_ALLOCATION);
+#ifndef JERRY_NDEBUG
+          PARSER_MINUS_EQUAL_U16 (context_p->context_stack_depth, PARSER_BLOCK_CONTEXT_STACK_ALLOCATION);
+#endif /* !JERRY_NDEBUG */
+
+          parser_emit_cbc (context_p, CBC_CONTEXT_END);
+          parser_set_branch_to_current_position (context_p, &block_context.branch);
+
+          parser_stack_iterator_init (context_p, &context_p->last_statement);
+        }
+#endif /* ENABLED (JERRY_ES2015) */
      }
      else if (context_p->stack_top_uint8 == PARSER_STATEMENT_TRY)
      {
@@ -2762,9 +3032,9 @@ consume_last_statement:
    }
  }

-  JERRY_ASSERT (context_p->stack_depth == 0);
+  JERRY_ASSERT (context_p->stack_depth == JERRY_GET_EXPECTED_DEPTH (context_p));
 #ifndef JERRY_NDEBUG
-  JERRY_ASSERT (context_p->context_stack_depth == 0);
+  JERRY_ASSERT (context_p->context_stack_depth == context_p->stack_depth);
 #endif /* !JERRY_NDEBUG */

  parser_stack_pop_uint8 (context_p);