JavaScriptCore/parser/ParserArena.h
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/JavaScriptCore/parser/ParserArena.h	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,130 @@
+/*
+ * Copyright (C) 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 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 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 ParserArena_h
+#define ParserArena_h
+
+#include "Identifier.h"
+#include <wtf/SegmentedVector.h>
+
+namespace JSC {
+
+    class ParserArenaDeletable;
+    class ParserArenaRefCounted;
+
+    class IdentifierArena : public FastAllocBase {
+    public:
+        ALWAYS_INLINE const Identifier& makeIdentifier(JSGlobalData*, const UChar* characters, size_t length);
+        const Identifier& makeNumericIdentifier(JSGlobalData*, double number);
+
+        void clear() { m_identifiers.clear(); }
+        bool isEmpty() const { return m_identifiers.isEmpty(); }
+
+    private:
+        typedef SegmentedVector<Identifier, 64> IdentifierVector;
+        IdentifierVector m_identifiers;
+    };
+
+    ALWAYS_INLINE const Identifier& IdentifierArena::makeIdentifier(JSGlobalData* globalData, const UChar* characters, size_t length)
+    {
+        m_identifiers.append(Identifier(globalData, characters, length));
+        return m_identifiers.last();
+    }
+
+    inline const Identifier& IdentifierArena::makeNumericIdentifier(JSGlobalData* globalData, double number)
+    {
+        m_identifiers.append(Identifier(globalData, UString::from(number)));
+        return m_identifiers.last();
+    }
+
+    class ParserArena : Noncopyable {
+    public:
+        ParserArena();
+        ~ParserArena();
+
+        void swap(ParserArena& otherArena)
+        {
+            std::swap(m_freeableMemory, otherArena.m_freeableMemory);
+            std::swap(m_freeablePoolEnd, otherArena.m_freeablePoolEnd);
+            m_identifierArena.swap(otherArena.m_identifierArena);
+            m_freeablePools.swap(otherArena.m_freeablePools);
+            m_deletableObjects.swap(otherArena.m_deletableObjects);
+            m_refCountedObjects.swap(otherArena.m_refCountedObjects);
+        }
+
+        void* allocateFreeable(size_t size)
+        {
+            ASSERT(size);
+            ASSERT(size <= freeablePoolSize);
+            size_t alignedSize = alignSize(size);
+            ASSERT(alignedSize <= freeablePoolSize);
+            if (UNLIKELY(static_cast<size_t>(m_freeablePoolEnd - m_freeableMemory) < alignedSize))
+                allocateFreeablePool();
+            void* block = m_freeableMemory;
+            m_freeableMemory += alignedSize;
+            return block;
+        }
+
+        void* allocateDeletable(size_t size)
+        {
+            ParserArenaDeletable* deletable = static_cast<ParserArenaDeletable*>(fastMalloc(size));
+            m_deletableObjects.append(deletable);
+            return deletable;
+        }
+
+        void derefWithArena(PassRefPtr<ParserArenaRefCounted>);
+        bool contains(ParserArenaRefCounted*) const;
+        ParserArenaRefCounted* last() const;
+        void removeLast();
+
+        bool isEmpty() const;
+        void reset();
+
+        IdentifierArena& identifierArena() { return *m_identifierArena; }
+
+    private:
+        static const size_t freeablePoolSize = 8000;
+
+        static size_t alignSize(size_t size)
+        {
+            return (size + sizeof(WTF::AllocAlignmentInteger) - 1) & ~(sizeof(WTF::AllocAlignmentInteger) - 1);
+        }
+
+        void* freeablePool();
+        void allocateFreeablePool();
+        void deallocateObjects();
+
+        char* m_freeableMemory;
+        char* m_freeablePoolEnd;
+
+        OwnPtr<IdentifierArena> m_identifierArena;
+        Vector<void*> m_freeablePools;
+        Vector<ParserArenaDeletable*> m_deletableObjects;
+        Vector<RefPtr<ParserArenaRefCounted> > m_refCountedObjects;
+    };
+
+}
+
+#endif