Add a limit assert.

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

Author: zherczeg

jerry-core/ecma/base/ecma-globals.h

@@ -686,7 +686,8 @@ typedef enum
   ECMA_STRING_CONTAINER_UINT32_IN_DESC, /**< actual data is UInt32-represeneted Number
                                              stored locally in the string's descriptor */
   ECMA_STRING_CONTAINER_MAGIC_STRING, /**< the ecma-string is equal to one of ECMA magic strings */
-  ECMA_STRING_CONTAINER_MAGIC_STRING_EX /**< the ecma-string is equal to one of external magic strings */
+  ECMA_STRING_CONTAINER_MAGIC_STRING_EX, /**< the ecma-string is equal to one of external magic strings */
+  ECMA_STRING_CONTAINER__COUNT /** count of container types */
 } ecma_string_container_t;
 
 /**

jerry-core/ecma/base/ecma-helpers-string.c

@@ -52,6 +52,12 @@ JERRY_STATIC_ASSERT ((int32_t) ECMA_STRING_MAX_CONCATENATION_LENGTH ==
 JERRY_STATIC_ASSERT (ECMA_STRING_CONTAINER_MASK + 1 == ECMA_STRING_REF_ONE,
                      ecma_string_ref_counter_should_start_after_the_container_field);
 
+/**
+ * The ecma string container types must be lower than the container mask.
+ */
+JERRY_STATIC_ASSERT (ECMA_STRING_CONTAINER_MASK + 1 >= ECMA_STRING_CONTAINER__COUNT,
+                     ecma_string_container_types_must_be_lower_than_the_container_mask);
+
 /**
  * The ecma string ref and container fields should fill the 16 bit field.
  */
@@ -506,10 +512,14 @@ ecma_deref_ecma_string (ecma_string_t *string_p) /**< ecma-string */
     case ECMA_STRING_CONTAINER_MAGIC_STRING_EX:
     {
       /* only the string descriptor itself should be freed */
+      break;
+    }
+    case ECMA_STRING_CONTAINER__COUNT:
+    {
+      JERRY_UNREACHABLE ();
     }
   }
 
-
   ecma_dealloc_string (string_p);
 } /* ecma_deref_ecma_string */
 
@@ -565,6 +575,10 @@ ecma_string_to_number (const ecma_string_t *str_p) /**< ecma-string */
 
       return num;
     }
+    case ECMA_STRING_CONTAINER__COUNT:
+    {
+      JERRY_UNREACHABLE ();
+    }
   }
 
   JERRY_UNREACHABLE ();