Optimize LCache entrys keys (#2767)

JerryScript-DCO-1.0-Signed-off-by: Robert Fancsik frobert@inf.u-szeged.hu

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

@@ -1489,6 +1489,14 @@ typedef struct
 } ecma_lit_storage_item_t;
 
 #ifndef CONFIG_ECMA_LCACHE_DISABLE
+/**
+ * Container of an LCache entry identifier
+ */
+#ifdef JERRY_CPOINTER_32_BIT
+typedef uint64_t ecma_lcache_hash_entry_id_t;
+#else /* !JERRY_CPOINTER_32_BIT */
+typedef uint32_t ecma_lcache_hash_entry_id_t;
+#endif /* JERRY_CPOINTER_32_BIT */
 
 /**
  * Entry of LCache hash table
@@ -1498,11 +1506,8 @@ typedef struct
   /** Pointer to a property of the object */
   ecma_property_t *prop_p;
 
-  /** Compressed pointer to object (ECMA_NULL_POINTER marks record empty) */
+  /** Entry identifier in LCache */
-  jmem_cpointer_t object_cp;
+  ecma_lcache_hash_entry_id_t id;
-
-  /** Compressed pointer to property's name */
-  jmem_cpointer_t prop_name_cp;
 } ecma_lcache_hash_entry_t;
 
 /**

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

@@ -33,6 +33,17 @@
  */
 #define ECMA_LCACHE_HASH_MASK (ECMA_LCACHE_HASH_ROWS_COUNT - 1)
 
+/**
+ * Bitshift index for creating property identifier
+ */
+#define ECMA_LCACHE_HASH_ENTRY_ID_SHIFT (8 * sizeof (jmem_cpointer_t))
+
+/**
+ * Create property identifier
+ */
+#define ECMA_LCACHE_CREATE_ID(object_cp, name_cp) \
+  (((ecma_lcache_hash_entry_id_t) (object_cp) << ECMA_LCACHE_HASH_ENTRY_ID_SHIFT) | (name_cp))
+
 /**
  * Invalidate specified LCache entry
  */
@@ -40,10 +51,10 @@ static inline void JERRY_ATTR_ALWAYS_INLINE
 ecma_lcache_invalidate_entry (ecma_lcache_hash_entry_t *entry_p) /**< entry to invalidate */
 {
   JERRY_ASSERT (entry_p != NULL);
-  JERRY_ASSERT (entry_p->object_cp != ECMA_NULL_POINTER);
+  JERRY_ASSERT (entry_p->id != 0);
   JERRY_ASSERT (entry_p->prop_p != NULL);
 
-  entry_p->object_cp = ECMA_NULL_POINTER;
+  entry_p->id = 0;
   ecma_set_property_lcached (entry_p->prop_p, false);
 } /* ecma_lcache_invalidate_entry */
 
@@ -54,11 +65,11 @@ ecma_lcache_invalidate_entry (ecma_lcache_hash_entry_t *entry_p) /**< entry to i
  */
 static inline size_t JERRY_ATTR_ALWAYS_INLINE
 ecma_lcache_row_index (jmem_cpointer_t object_cp, /**< compressed pointer to object */
-                       lit_string_hash_t name_hash) /**< property name hash */
+                       jmem_cpointer_t name_cp) /**< compressed pointer to property name */
 {
-  /* Randomize the hash of the property name with the object pointer using a xor operation,
+  /* Randomize the property name with the object pointer using a xor operation,
    * so properties of different objects with the same name can be cached effectively. */
-  return (size_t) ((name_hash ^ object_cp) & ECMA_LCACHE_HASH_MASK);
+  return (size_t) ((name_cp ^ object_cp) & ECMA_LCACHE_HASH_MASK);
 } /* ecma_lcache_row_index */
 
 /**
@@ -79,14 +90,13 @@ ecma_lcache_insert (ecma_object_t *object_p, /**< object */
 
   ECMA_SET_NON_NULL_POINTER (object_cp, object_p);
 
-  lit_string_hash_t name_hash = ecma_string_get_property_name_hash (*prop_p, name_cp);
+  size_t row_index = ecma_lcache_row_index (object_cp, name_cp);
-  size_t row_index = ecma_lcache_row_index (object_cp, name_hash);
   ecma_lcache_hash_entry_t *entries_p = JERRY_CONTEXT (lcache) [row_index];
 
   uint32_t entry_index;
   for (entry_index = 0; entry_index < ECMA_LCACHE_HASH_ROW_LENGTH; entry_index++)
   {
-    if (entries_p[entry_index].object_cp == ECMA_NULL_POINTER)
+    if (entries_p[entry_index].id == 0)
     {
       break;
     }
@@ -102,14 +112,12 @@ ecma_lcache_insert (ecma_object_t *object_p, /**< object */
     {
       entries_p[i] = entries_p[i - 1];
     }
-
     entry_index = 0;
   }
 
   ecma_lcache_hash_entry_t *entry_p = entries_p + entry_index;
-  ECMA_SET_NON_NULL_POINTER (entry_p->object_cp, object_p);
-  entry_p->prop_name_cp = name_cp;
   entry_p->prop_p = prop_p;
+  entry_p->id = ECMA_LCACHE_CREATE_ID (object_cp, name_cp);
 
   ecma_set_property_lcached (entry_p->prop_p, true);
 } /* ecma_lcache_insert */
@@ -132,53 +140,32 @@ ecma_lcache_lookup (ecma_object_t *object_p, /**< object */
 
   ecma_property_t prop_name_type;
   jmem_cpointer_t prop_name_cp;
-  lit_string_hash_t name_hash;
 
   if (ECMA_IS_DIRECT_STRING (prop_name_p))
   {
     prop_name_type = (ecma_property_t) ECMA_GET_DIRECT_STRING_TYPE (prop_name_p);
-
+    prop_name_cp = (jmem_cpointer_t) ECMA_GET_DIRECT_STRING_VALUE (prop_name_p);
-    uintptr_t value = ECMA_GET_DIRECT_STRING_VALUE (prop_name_p);
-    prop_name_cp = (jmem_cpointer_t) value;
-    name_hash = (lit_string_hash_t) value;
-
-    if (prop_name_type == ECMA_DIRECT_STRING_MAGIC_EX)
-    {
-      name_hash = (lit_string_hash_t) (name_hash + LIT_MAGIC_STRING__COUNT);
-    }
   }
   else
   {
     prop_name_type = ECMA_DIRECT_STRING_PTR;
-
     ECMA_SET_NON_NULL_POINTER (prop_name_cp, prop_name_p);
-    name_hash = prop_name_p->hash;
   }
 
-  size_t row_index = ecma_lcache_row_index (object_cp, name_hash);
+  size_t row_index = ecma_lcache_row_index (object_cp, prop_name_cp);
 
   ecma_lcache_hash_entry_t *entry_p = JERRY_CONTEXT (lcache) [row_index];
   ecma_lcache_hash_entry_t *entry_end_p = entry_p + ECMA_LCACHE_HASH_ROW_LENGTH;
 
+  ecma_lcache_hash_entry_id_t id = ECMA_LCACHE_CREATE_ID (object_cp, prop_name_cp);
+
   while (entry_p < entry_end_p)
   {
-    if (entry_p->object_cp == object_cp
+    if (entry_p->id == id && ECMA_PROPERTY_GET_NAME_TYPE (*entry_p->prop_p) == prop_name_type)
-        && entry_p->prop_name_cp == prop_name_cp)
     {
-      ecma_property_t *prop_p = entry_p->prop_p;
+      JERRY_ASSERT (entry_p->prop_p != NULL && ecma_is_property_lcached (entry_p->prop_p));
-
+      return entry_p->prop_p;
-      JERRY_ASSERT (prop_p != NULL && ecma_is_property_lcached (prop_p));
-
-      if (ECMA_PROPERTY_GET_NAME_TYPE (*prop_p) == prop_name_type)
-      {
-        return prop_p;
-      }
     }
-    else
-    {
-      /* They can be equal, but generic string comparison is too costly. */
-    }
-
     entry_p++;
   }
 
@@ -202,8 +189,7 @@ ecma_lcache_invalidate (ecma_object_t *object_p, /**< object */
   jmem_cpointer_t object_cp;
   ECMA_SET_NON_NULL_POINTER (object_cp, object_p);
 
-  lit_string_hash_t name_hash = ecma_string_get_property_name_hash (*prop_p, name_cp);
+  size_t row_index = ecma_lcache_row_index (object_cp, name_cp);
-  size_t row_index = ecma_lcache_row_index (object_cp, name_hash);
   ecma_lcache_hash_entry_t *entry_p = JERRY_CONTEXT (lcache) [row_index];
 
   while (true)
@@ -211,9 +197,9 @@ ecma_lcache_invalidate (ecma_object_t *object_p, /**< object */
     /* The property must be present. */
     JERRY_ASSERT (entry_p - JERRY_CONTEXT (lcache) [row_index] < ECMA_LCACHE_HASH_ROW_LENGTH);
 
-    if (entry_p->object_cp != ECMA_NULL_POINTER && entry_p->prop_p == prop_p)
+    if (entry_p->id != 0 && entry_p->prop_p == prop_p)
     {
-      JERRY_ASSERT (entry_p->object_cp == object_cp);
+      JERRY_ASSERT (entry_p->id == ECMA_LCACHE_CREATE_ID (object_cp, name_cp));
 
       ecma_lcache_invalidate_entry (entry_p);
       return;