JavaScriptCore/parser/ParserArena.cpp
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/JavaScriptCore/parser/ParserArena.cpp	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,125 @@
+/*
+ * Copyright (C) 2009, 2010 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. 
+ */
+
+#include "config.h"
+#include "ParserArena.h"
+
+#include "Nodes.h"
+#include <wtf/PassOwnPtr.h>
+
+namespace JSC {
+
+ParserArena::ParserArena()
+    : m_freeableMemory(0)
+    , m_freeablePoolEnd(0)
+    , m_identifierArena(adoptPtr(new IdentifierArena))
+{
+}
+
+inline void* ParserArena::freeablePool()
+{
+    ASSERT(m_freeablePoolEnd);
+    return m_freeablePoolEnd - freeablePoolSize;
+}
+
+inline void ParserArena::deallocateObjects()
+{
+    if (m_freeablePoolEnd)
+        fastFree(freeablePool());
+
+    size_t size = m_freeablePools.size();
+    for (size_t i = 0; i < size; ++i)
+        fastFree(m_freeablePools[i]);
+
+    size = m_deletableObjects.size();
+    for (size_t i = 0; i < size; ++i) {
+        ParserArenaDeletable* object = m_deletableObjects[i];
+        object->~ParserArenaDeletable();
+        fastFree(object);
+    }
+}
+
+ParserArena::~ParserArena()
+{
+    deallocateObjects();
+}
+
+bool ParserArena::contains(ParserArenaRefCounted* object) const
+{
+    return m_refCountedObjects.find(object) != notFound;
+}
+
+ParserArenaRefCounted* ParserArena::last() const
+{
+    return m_refCountedObjects.last().get();
+}
+
+void ParserArena::removeLast()
+{
+    m_refCountedObjects.removeLast();
+}
+
+void ParserArena::reset()
+{
+    // Since this code path is used only when parsing fails, it's not bothering to reuse
+    // any of the memory the arena allocated. We could improve that later if we want to
+    // efficiently reuse the same arena.
+
+    deallocateObjects();
+
+    m_freeableMemory = 0;
+    m_freeablePoolEnd = 0;
+    m_identifierArena->clear();
+    m_freeablePools.clear();
+    m_deletableObjects.clear();
+    m_refCountedObjects.clear();
+}
+
+void ParserArena::allocateFreeablePool()
+{
+    if (m_freeablePoolEnd)
+        m_freeablePools.append(freeablePool());
+
+    char* pool = static_cast<char*>(fastMalloc(freeablePoolSize));
+    m_freeableMemory = pool;
+    m_freeablePoolEnd = pool + freeablePoolSize;
+    ASSERT(freeablePool() == pool);
+}
+
+bool ParserArena::isEmpty() const
+{
+    return !m_freeablePoolEnd
+        && m_identifierArena->isEmpty()
+        && m_freeablePools.isEmpty()
+        && m_deletableObjects.isEmpty()
+        && m_refCountedObjects.isEmpty();
+}
+
+void ParserArena::derefWithArena(PassRefPtr<ParserArenaRefCounted> object)
+{
+    m_refCountedObjects.append(object);
+}
+
+}