Changeset 27093 in webkit for trunk/JavaScriptCore/wtf/HashTable.h

Timestamp:

Oct 25, 2007, 11:55:36 PM (18 years ago)

Author:

ggaren

Message:

Reviewed by Maciej Stachowiak.

Tweaked the inner hashtable lookup loop to remove a branch in the "not
found" case. .5% speedup on SunSpider.

• JavaScriptCore.xcodeproj/project.pbxproj:
• wtf/HashTable.h: (WTF::::lookup):

File:

• trunk/JavaScriptCore/wtf/HashTable.h (modified) (2 diffs)

trunk/JavaScriptCore/wtf/HashTable.h

@@ -397 +397 @@
 #endif
 
-        ValueType *table = m_table;
-        ValueType *entry;
-        ValueType *deletedEntry = 0;
-        while (!isEmptyBucket(*(entry = table + i))) {
+        ValueType* table = m_table;
+        ValueType* deletedEntry = 0;
+
+        while (1) {
+            ValueType* entry = table + i;
+
+            if (isEmptyBucket(*entry))
+                return makeLookupResult(deletedEntry ? deletedEntry : entry, false, h);
+            
             if (isDeletedBucket(*entry))
                 deletedEntry = entry;
             else if (HashTranslator::equal(Extractor::extract(*entry), key))
                 return makeLookupResult(entry, true, h);
+
 #if DUMP_HASHTABLE_STATS
             ++probeCount;
@@ -413 +419 @@
             i = (i + k) & sizeMask;
         }
-
-        return makeLookupResult(deletedEntry ? deletedEntry : entry, false, h);
-    }
-
+    }
 
     template<typename Key, typename Value, typename Extractor, typename HashFunctions, typename Traits, typename KeyTraits>