runtime/RegExpCache.cpp

   1 /*
   2  * Copyright (C) 2010 University of Szeged
   3  * Copyright (C) 2010 Renata Hodovan (hodovan@inf.u-szeged.hu)
   4  * Copyright (C) 2012 Apple Inc. All rights reserved.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY UNIVERSITY OF SZEGED ``AS IS'' AND ANY
  17  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL UNIVERSITY OF SZEGED OR
  20  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  21  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  22  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  23  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  24  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #include "config.h"
  30 #include "RegExpCache.h"
  31
  32 #include "JSCInlines.h"
  33 #include "RegExpObject.h"
  34 #include "StrongInlines.h"
  35
  36 namespace JSC {
  37
  38 RegExp* RegExpCache::lookupOrCreate(const String& patternString, RegExpFlags flags)
  39 {
  40     RegExpKey key(flags, patternString);
  41     if (RegExp* regExp = m_weakCache.get(key))
  42         return regExp;
  43
  44     RegExp* regExp = RegExp::createWithoutCaching(*m_vm, patternString, flags);
  45 #if ENABLE(REGEXP_TRACING)
  46     m_vm->addRegExpToTrace(regExp);
  47 #endif
  48
  49     weakAdd(m_weakCache, key, Weak<RegExp>(regExp, this));
  50     return regExp;
  51 }
  52
  53 RegExpCache::RegExpCache(VM* vm)
  54     : m_nextEntryInStrongCache(0)
  55     , m_vm(vm)
  56 {
  57 }
  58
  59 void RegExpCache::finalize(Handle<Unknown> handle, void*)
  60 {
  61     RegExp* regExp = static_cast<RegExp*>(handle.get().asCell());
  62     weakRemove(m_weakCache, regExp->key(), regExp);
  63     regExp->invalidateCode();
  64 }
  65
  66 void RegExpCache::addToStrongCache(RegExp* regExp)
  67 {
  68     String pattern = regExp->pattern();
  69     if (pattern.length() > maxStrongCacheablePatternLength)
  70         return;
  71     m_strongCache[m_nextEntryInStrongCache].set(*m_vm, regExp);
  72     m_nextEntryInStrongCache++;
  73     if (m_nextEntryInStrongCache == maxStrongCacheableEntries)
  74         m_nextEntryInStrongCache = 0;
  75 }
  76
  77 void RegExpCache::invalidateCode()
  78 {
  79     for (int i = 0; i < maxStrongCacheableEntries; i++)
  80         m_strongCache[i].clear();
  81     m_nextEntryInStrongCache = 0;
  82
  83     RegExpCacheMap::iterator end = m_weakCache.end();
  84     for (RegExpCacheMap::iterator it = m_weakCache.begin(); it != end; ++it) {
  85         RegExp* regExp = it->value.get();
  86         if (!regExp) // Skip zombies.
  87             continue;
  88         regExp->invalidateCode();
  89     }
  90 }
  91
  92 }