runtime/RegExpCache.h

   1 /*
   2  * Copyright (C) 2010 University of Szeged
   3  * Copyright (C) 2010 Renata Hodovan (hodovan@inf.u-szeged.hu)
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY UNIVERSITY OF SZEGED ``AS IS'' AND ANY
  16  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  18  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL UNIVERSITY OF SZEGED OR
  19  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  20  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  21  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  22  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  23  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  25  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #include "RegExp.h"
  29 #include "RegExpKey.h"
  30 #include "Strong.h"
  31 #include "Weak.h"
  32 #include "WeakInlines.h"
  33 #include <array>
  34 #include <wtf/HashMap.h>
  35
  36 #ifndef RegExpCache_h
  37 #define RegExpCache_h
  38
  39 namespace JSC {
  40
  41 class RegExpCache : private WeakHandleOwner {
  42     WTF_MAKE_FAST_ALLOCATED;
  43
  44     friend class RegExp;
  45     typedef HashMap<RegExpKey, Weak<RegExp>> RegExpCacheMap;
  46
  47 public:
  48     RegExpCache(VM* vm);
  49     void invalidateCode();
  50
  51 private:
  52
  53     static const unsigned maxStrongCacheablePatternLength = 256;
  54
  55     static const int maxStrongCacheableEntries = 32;
  56
  57     virtual void finalize(Handle<Unknown>, void* context) override;
  58
  59     RegExp* lookupOrCreate(const WTF::String& patternString, RegExpFlags);
  60     void addToStrongCache(RegExp*);
  61     RegExpCacheMap m_weakCache; // Holds all regular expressions currently live.
  62     int m_nextEntryInStrongCache;
  63     std::array<Strong<RegExp>, maxStrongCacheableEntries> m_strongCache; // Holds a select few regular expressions that have compiled and executed
  64     VM* m_vm;
  65 };
  66
  67 } // namespace JSC
  68
  69 #endif // RegExpCache_h