JavaScriptCore-903.tar.gz

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

diff --git a/parser/ParserArena.h b/parser/ParserArena.h
index eef8e939394c1cff51222066000607f7d07284d7..1563e498f416cef00c3cb9fff3b6a52426ba3794 100644 (file)
--- a/parser/ParserArena.h
+++ b/parser/ParserArena.h
@@ -34,32 +34,53 @@ namespace JSC {
     class ParserArenaDeletable;
     class ParserArenaRefCounted;
 
-    class IdentifierArena : public FastAllocBase {
+    class IdentifierArena {
+        WTF_MAKE_FAST_ALLOCATED;
     public:
+        IdentifierArena()
+        {
+            clear();
+        }
+
         ALWAYS_INLINE const Identifier& makeIdentifier(JSGlobalData*, const UChar* characters, size_t length);
         const Identifier& makeNumericIdentifier(JSGlobalData*, double number);
 
-        void clear() { m_identifiers.clear(); }
+        void clear()
+        {
+            m_identifiers.clear();
+            for (unsigned  i = 0; i < 128; i++)
+                m_shortIdentifiers[i] = 0;
+        }
         bool isEmpty() const { return m_identifiers.isEmpty(); }
 
     private:
+        static const int MaximumCachableCharacter = 128;
         typedef SegmentedVector<Identifier, 64> IdentifierVector;
         IdentifierVector m_identifiers;
+        FixedArray<Identifier*, MaximumCachableCharacter> m_shortIdentifiers;
     };
 
     ALWAYS_INLINE const Identifier& IdentifierArena::makeIdentifier(JSGlobalData* globalData, const UChar* characters, size_t length)
     {
+        if (length == 1 && characters[0] < MaximumCachableCharacter) {
+            if (Identifier* ident = m_shortIdentifiers[characters[0]])
+                return *ident;
+            m_identifiers.append(Identifier(globalData, characters, length));
+            m_shortIdentifiers[characters[0]] = &m_identifiers.last();
+            return m_identifiers.last();
+        }
         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)));
+        m_identifiers.append(Identifier(globalData, UString::number(number)));
         return m_identifiers.last();
     }
 
-    class ParserArena : Noncopyable {
+    class ParserArena {
+        WTF_MAKE_NONCOPYABLE(ParserArena);
     public:
         ParserArena();
         ~ParserArena();