JavaScriptCore/runtime/StructureTransitionTable.h
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/JavaScriptCore/runtime/StructureTransitionTable.h	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2008, 2009 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ */
+
+#ifndef StructureTransitionTable_h
+#define StructureTransitionTable_h
+
+#include "UString.h"
+#include <wtf/HashFunctions.h>
+#include <wtf/HashMap.h>
+#include <wtf/HashTraits.h>
+#include <wtf/OwnPtr.h>
+#include <wtf/RefPtr.h>
+
+namespace JSC {
+
+    class Structure;
+
+    struct StructureTransitionTableHash {
+        typedef std::pair<RefPtr<UString::Rep>, unsigned> Key;
+        static unsigned hash(const Key& p)
+        {
+            return p.first->existingHash();
+        }
+
+        static bool equal(const Key& a, const Key& b)
+        {
+            return a == b;
+        }
+
+        static const bool safeToCompareToEmptyOrDeleted = true;
+    };
+
+    struct StructureTransitionTableHashTraits {
+        typedef WTF::HashTraits<RefPtr<UString::Rep> > FirstTraits;
+        typedef WTF::GenericHashTraits<unsigned> SecondTraits;
+        typedef std::pair<FirstTraits::TraitType, SecondTraits::TraitType > TraitType;
+
+        static const bool emptyValueIsZero = FirstTraits::emptyValueIsZero && SecondTraits::emptyValueIsZero;
+        static TraitType emptyValue() { return std::make_pair(FirstTraits::emptyValue(), SecondTraits::emptyValue()); }
+
+        static const bool needsDestruction = FirstTraits::needsDestruction || SecondTraits::needsDestruction;
+
+        static void constructDeletedValue(TraitType& slot) { FirstTraits::constructDeletedValue(slot.first); }
+        static bool isDeletedValue(const TraitType& value) { return FirstTraits::isDeletedValue(value.first); }
+    };
+
+} // namespace JSC
+
+#endif // StructureTransitionTable_h