JavaScriptCore-1218.tar.gz

[apple/javascriptcore.git] / parser / ParserArena.cpp

diff --git a/parser/ParserArena.cpp b/parser/ParserArena.cpp
index 261750668efd779f14797ab6c3cabec5c4b24ef5..c53f30753f2f712bf9b751c0684cd6dee5a240a1 100644 (file)
--- a/parser/ParserArena.cpp
+++ b/parser/ParserArena.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009 Apple Inc. All rights reserved.
+ * 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
@@ -27,12 +27,39 @@
 #include "ParserArena.h"
 
 #include "Nodes.h"
+#include <wtf/PassOwnPtr.h>
 
 namespace JSC {
 
+ParserArena::ParserArena()
+    : m_freeableMemory(0)
+    , m_freeablePoolEnd(0)
+{
+}
+
+inline void* ParserArena::freeablePool()
+{
+    ASSERT(m_freeablePoolEnd);
+    return m_freeablePoolEnd - freeablePoolSize;
+}
+
+inline void ParserArena::deallocateObjects()
+{
+    size_t size = m_deletableObjects.size();
+    for (size_t i = 0; i < size; ++i)
+        m_deletableObjects[i]->~ParserArenaDeletable();
+
+    if (m_freeablePoolEnd)
+        fastFree(freeablePool());
+
+    size = m_freeablePools.size();
+    for (size_t i = 0; i < size; ++i)
+        fastFree(m_freeablePools[i]);
+}
+
 ParserArena::~ParserArena()
 {
-    deleteAllValues(m_deletableObjects);
+    deallocateObjects();
 }
 
 bool ParserArena::contains(ParserArenaRefCounted* object) const
@@ -52,9 +79,44 @@ void ParserArena::removeLast()
 
 void ParserArena::reset()
 {
-    deleteAllValues(m_deletableObjects);
-    m_deletableObjects.shrink(0);
-    m_refCountedObjects.shrink(0);
+    // 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;
+    if (m_identifierArena)
+        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 || m_identifierArena->isEmpty())
+        && m_freeablePools.isEmpty()
+        && m_deletableObjects.isEmpty()
+        && m_refCountedObjects.isEmpty();
+}
+
+void ParserArena::derefWithArena(PassRefPtr<ParserArenaRefCounted> object)
+{
+    m_refCountedObjects.append(object);
 }
 
 }