dfg/DFGDesiredWatchpoints.h

   1 /*
   2  * Copyright (C) 2013 Apple Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
  14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
  17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #ifndef DFGDesiredWatchpoints_h
  27 #define DFGDesiredWatchpoints_h
  28
  29 #if ENABLE(DFG_JIT)
  30
  31 #include "CodeOrigin.h"
  32 #include "DFGCommonData.h"
  33 #include "JSArrayBufferView.h"
  34 #include "Watchpoint.h"
  35 #include <wtf/HashMap.h>
  36 #include <wtf/HashSet.h>
  37 #include <wtf/Noncopyable.h>
  38 #include <wtf/Vector.h>
  39
  40 namespace JSC { namespace DFG {
  41
  42 template<typename WatchpointSetType>
  43 struct WatchpointForGenericWatchpointSet {
  44     WatchpointForGenericWatchpointSet()
  45         : m_exitKind(ExitKindUnset)
  46         , m_set(0)
  47     {
  48     }
  49
  50     WatchpointForGenericWatchpointSet(
  51         CodeOrigin codeOrigin, ExitKind exitKind, WatchpointSetType* set)
  52         : m_codeOrigin(codeOrigin)
  53         , m_exitKind(exitKind)
  54         , m_set(set)
  55     {
  56     }
  57
  58     CodeOrigin m_codeOrigin;
  59     ExitKind m_exitKind;
  60     WatchpointSetType* m_set;
  61 };
  62
  63 template<typename T>
  64 struct GenericSetAdaptor {
  65     static void add(CodeBlock*, T* set, Watchpoint* watchpoint)
  66     {
  67         return set->add(watchpoint);
  68     }
  69     static bool hasBeenInvalidated(T* set) { return set->hasBeenInvalidated(); }
  70 };
  71
  72 struct ArrayBufferViewWatchpointAdaptor {
  73     static void add(CodeBlock*, JSArrayBufferView*, Watchpoint*);
  74     static bool hasBeenInvalidated(JSArrayBufferView* view)
  75     {
  76         bool result = !view->length();
  77         WTF::loadLoadFence();
  78         return result;
  79     }
  80 };
  81
  82 template<typename WatchpointSetType, typename Adaptor = GenericSetAdaptor<WatchpointSetType>>
  83 class GenericDesiredWatchpoints {
  84 #if !ASSERT_DISABLED
  85     typedef HashMap<WatchpointSetType*, bool> StateMap;
  86 #endif
  87 public:
  88     GenericDesiredWatchpoints()
  89         : m_reallyAdded(false)
  90     {
  91     }
  92
  93     void addLazily(WatchpointSetType* set)
  94     {
  95         m_sets.add(set);
  96     }
  97
  98     void addLazily(CodeOrigin codeOrigin, ExitKind exitKind, WatchpointSetType* set)
  99     {
 100         m_profiledWatchpoints.append(
 101             WatchpointForGenericWatchpointSet<WatchpointSetType>(codeOrigin, exitKind, set));
 102     }
 103
 104     void reallyAdd(CodeBlock* codeBlock, CommonData& common)
 105     {
 106         RELEASE_ASSERT(!m_reallyAdded);
 107
 108         typename HashSet<WatchpointSetType*>::iterator iter = m_sets.begin();
 109         typename HashSet<WatchpointSetType*>::iterator end = m_sets.end();
 110         for (; iter != end; ++iter) {
 111             common.watchpoints.append(CodeBlockJettisoningWatchpoint(codeBlock));
 112             Adaptor::add(codeBlock, *iter, &common.watchpoints.last());
 113         }
 114
 115         for (unsigned i = m_profiledWatchpoints.size(); i--;) {
 116             WatchpointForGenericWatchpointSet<WatchpointSetType> watchpoint =
 117                 m_profiledWatchpoints[i];
 118             common.profiledWatchpoints.append(
 119                 ProfiledCodeBlockJettisoningWatchpoint(watchpoint.m_codeOrigin, watchpoint.m_exitKind, codeBlock));
 120             Adaptor::add(codeBlock, watchpoint.m_set, &common.profiledWatchpoints.last());
 121         }
 122
 123         m_reallyAdded = true;
 124     }
 125
 126     bool areStillValid() const
 127     {
 128         typename HashSet<WatchpointSetType*>::iterator iter = m_sets.begin();
 129         typename HashSet<WatchpointSetType*>::iterator end = m_sets.end();
 130         for (; iter != end; ++iter) {
 131             if (Adaptor::hasBeenInvalidated(*iter))
 132                 return false;
 133         }
 134
 135         for (unsigned i = m_profiledWatchpoints.size(); i--;) {
 136             if (Adaptor::hasBeenInvalidated(m_profiledWatchpoints[i].m_set))
 137                 return false;
 138         }
 139
 140         return true;
 141     }
 142
 143 #if ASSERT_DISABLED
 144     bool isStillValid(WatchpointSetType* set)
 145     {
 146         return !Adaptor::hasBeenInvalidated(set);
 147     }
 148
 149     bool shouldAssumeMixedState(WatchpointSetType*)
 150     {
 151         return true;
 152     }
 153 #else
 154     bool isStillValid(WatchpointSetType* set)
 155     {
 156         bool result = !Adaptor::hasBeenInvalidated(set);
 157         m_firstKnownState.add(set, result);
 158         return result;
 159     }
 160
 161     bool shouldAssumeMixedState(WatchpointSetType* set)
 162     {
 163         typename StateMap::iterator iter = m_firstKnownState.find(set);
 164         if (iter == m_firstKnownState.end())
 165             return false;
 166
 167         return iter->value != !Adaptor::hasBeenInvalidated(set);
 168     }
 169 #endif
 170
 171     bool isValidOrMixed(WatchpointSetType* set)
 172     {
 173         return isStillValid(set) || shouldAssumeMixedState(set);
 174     }
 175
 176 private:
 177     Vector<WatchpointForGenericWatchpointSet<WatchpointSetType>> m_profiledWatchpoints;
 178     HashSet<WatchpointSetType*> m_sets;
 179 #if !ASSERT_DISABLED
 180     StateMap m_firstKnownState;
 181 #endif
 182     bool m_reallyAdded;
 183 };
 184
 185 class DesiredWatchpoints {
 186 public:
 187     DesiredWatchpoints();
 188     ~DesiredWatchpoints();
 189
 190     void addLazily(WatchpointSet*);
 191     void addLazily(InlineWatchpointSet&);
 192     void addLazily(JSArrayBufferView*);
 193     void addLazily(CodeOrigin, ExitKind, WatchpointSet*);
 194     void addLazily(CodeOrigin, ExitKind, InlineWatchpointSet&);
 195
 196     void reallyAdd(CodeBlock*, CommonData&);
 197
 198     bool areStillValid() const;
 199
 200     bool isStillValid(WatchpointSet* set)
 201     {
 202         return m_sets.isStillValid(set);
 203     }
 204     bool isStillValid(InlineWatchpointSet& set)
 205     {
 206         return m_inlineSets.isStillValid(&set);
 207     }
 208     bool isStillValid(JSArrayBufferView* view)
 209     {
 210         return m_bufferViews.isStillValid(view);
 211     }
 212     bool shouldAssumeMixedState(WatchpointSet* set)
 213     {
 214         return m_sets.shouldAssumeMixedState(set);
 215     }
 216     bool shouldAssumeMixedState(InlineWatchpointSet& set)
 217     {
 218         return m_inlineSets.shouldAssumeMixedState(&set);
 219     }
 220     bool shouldAssumeMixedState(JSArrayBufferView* view)
 221     {
 222         return m_bufferViews.shouldAssumeMixedState(view);
 223     }
 224     bool isValidOrMixed(WatchpointSet* set)
 225     {
 226         return m_sets.isValidOrMixed(set);
 227     }
 228     bool isValidOrMixed(InlineWatchpointSet& set)
 229     {
 230         return m_inlineSets.isValidOrMixed(&set);
 231     }
 232     bool isValidOrMixed(JSArrayBufferView* view)
 233     {
 234         return m_bufferViews.isValidOrMixed(view);
 235     }
 236
 237 private:
 238     GenericDesiredWatchpoints<WatchpointSet> m_sets;
 239     GenericDesiredWatchpoints<InlineWatchpointSet> m_inlineSets;
 240     GenericDesiredWatchpoints<JSArrayBufferView, ArrayBufferViewWatchpointAdaptor> m_bufferViews;
 241 };
 242
 243 } } // namespace JSC::DFG
 244
 245 #endif // ENABLE(DFG_JIT)
 246
 247 #endif // DFGDesiredWatchpoints_h
 248