Check reference count of objects

Throw an error if the object reference count reached the limit.
Related issue: #118

JerryScript-DCO-1.0-Signed-off-by: László Langó llango.u-szeged@partner.samsung.com

jerry-core/config.h

@@ -82,6 +82,8 @@
  */
 #define CONFIG_ECMA_REFERENCE_COUNTER_WIDTH (10)
 
+#define CONFIG_ECMA_REFERENCE_COUNTER_LIMIT ((1u << CONFIG_ECMA_REFERENCE_COUNTER_WIDTH) - 1u)
+
 /**
  * Maximum length of strings' concatenation
  */

jerry-core/ecma/base/ecma-gc.c

@@ -211,7 +211,16 @@ ecma_init_gc_info (ecma_object_t *object_p) /**< object */
 void
 ecma_ref_object (ecma_object_t *object_p) /**< object */
 {
-  ecma_gc_set_object_refs (object_p, ecma_gc_get_object_refs (object_p) + 1);
+  uint32_t ref_cnt = ecma_gc_get_object_refs (object_p);
+
+  if (ref_cnt < (uint32_t) CONFIG_ECMA_REFERENCE_COUNTER_LIMIT)
+  {
+    ecma_gc_set_object_refs (object_p, ref_cnt + 1);
+  }
+  else
+  {
+    jerry_fatal (ERR_REF_COUNT_LIMIT);
+  }
 } /* ecma_ref_object */
 
 /**

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

@@ -1334,11 +1334,10 @@ ecma_get_property_descriptor_from_property (ecma_property_t *prop_p) /**< proper
 void
 ecma_bytecode_ref (ecma_compiled_code_t *bytecode_p) /**< byte code pointer */
 {
-  /* Abort program if maximum reference number is reached.
-   * Note: This is not tested for objects. */
+  /* Abort program if maximum reference number is reached. */
   if ((bytecode_p->status_flags >> ECMA_BYTECODE_REF_SHIFT) >= 0x3ff)
   {
-    jerry_fatal (ERR_UNIMPLEMENTED_CASE);
+    jerry_fatal (ERR_REF_COUNT_LIMIT);
   }
 
   bytecode_p->status_flags = (uint16_t) (bytecode_p->status_flags + (1 << ECMA_BYTECODE_REF_SHIFT));

jerry-core/jerry.h

@@ -50,6 +50,7 @@ typedef enum
 {
   ERR_OUT_OF_MEMORY = 10,
   ERR_SYSCALL = 11,
+  ERR_REF_COUNT_LIMIT = 12,
   ERR_UNIMPLEMENTED_CASE = 118,
   ERR_FAILED_INTERNAL_ASSERTION = 120
 } jerry_fatal_code_t;

jerry-core/jrt/jrt-fatals.c

@@ -47,6 +47,11 @@ jerry_fatal (jerry_fatal_code_t code) /**< status code */
       /* print nothing as it may invoke syscall recursively */
       break;
     }
+    case ERR_REF_COUNT_LIMIT:
+    {
+      printf ("ERR_REF_COUNT_LIMIT\n");
+      break;
+    }
     case ERR_UNIMPLEMENTED_CASE:
     {
       printf ("ERR_UNIMPLEMENTED_CASE\n");