Changeset 2769 in webkit for trunk/JavaScriptCore/kjs/property_map.cpp

Timestamp:

Nov 19, 2002, 5:23:02 PM (23 years ago)

Author:

darin

Message:

• another step towards atomic identifiers; storing hash in the string rep. gives about a 1.5% speedup in the JavaScript iBench

• kjs/ustring.h: Add a hash field to UString::Rep.
• kjs/ustring.cpp: (UString::Rep::create): Set hash to uninitialized value. (UString::Rep::destroy): Do the deleting in her, and call Identifier if needed. (UString::Rep::computeHash): Added. (UString::append): Set hash to 0 when modifying the string in place. (UString::operator=): Ditto.

• kjs/property_map.cpp: Use the hash from UString.

• kjs/identifier.h: Added aboutToDestroyUStringRep.
• kjs/identifier.cpp: (Identifier::aboutToDestroyUStringRep): Added.

File:

• trunk/JavaScriptCore/kjs/property_map.cpp (modified) (1 diff)

trunk/JavaScriptCore/kjs/property_map.cpp

@@ -65 +65 @@
 }
 
-int PropertyMap::hash(const UString::Rep *s) const
-{
-    int h = 0;
-    int length = s->len;
-    int prefixLength = length < 8 ? length : 8;
-    for (int i = 0; i < prefixLength; i++)
-        h = (127 * h + s->dat[i].unicode()) & _tableSizeHashMask;
-    int suffixPosition = length < 16 ? 8 : length - 8;
-    for (int i = suffixPosition; i < length; i++)
-        h = (127 * h + s->dat[i].unicode()) & _tableSizeHashMask;
-    return h;
+inline int PropertyMap::hash(const UString::Rep *s) const
+{
+    return s->hash() & _tableSizeHashMask;
 }