runtime/FunctionHasExecutedCache.cpp

   1 /*
   2  * Copyright (C) 2014 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 #include "config.h"
  27 #include "FunctionHasExecutedCache.h"
  28
  29 #include <limits.h>
  30
  31 namespace JSC {
  32
  33 bool FunctionHasExecutedCache::hasExecutedAtOffset(intptr_t id, unsigned offset)
  34 {
  35     if (m_rangeMap.find(id) == m_rangeMap.end())
  36         return false;
  37
  38     RangeMap& map = m_rangeMap.find(id)->second;
  39     unsigned distance = UINT_MAX;
  40     bool hasExecuted = false;
  41     for (auto iter = map.begin(), end = map.end(); iter != end; ++iter) {
  42         const FunctionRange& range = iter->first;
  43         if (range.m_start <= offset && offset <= range.m_end && range.m_end - range.m_start < distance) {
  44             hasExecuted = iter->second;
  45             distance = range.m_end - range.m_start;
  46         }
  47     }
  48
  49     return hasExecuted;
  50 }
  51
  52 void FunctionHasExecutedCache::insertUnexecutedRange(intptr_t id, unsigned start, unsigned end)
  53 {
  54     if (m_rangeMap.find(id) == m_rangeMap.end()) {
  55         RangeMap map;
  56         m_rangeMap[id] = map;
  57     }
  58
  59     RangeMap& map = m_rangeMap.find(id)->second;
  60     FunctionRange range;
  61     range.m_start = start;
  62     range.m_end = end;
  63     // Only insert unexecuted ranges once for a given sourceID because we may run into a situation where an executable executes, then is GCed, and then is allocated again,
  64     // and tries to reinsert itself, claiming it has never run, but this is false because it indeed already executed.
  65     if (map.find(range) == map.end())
  66         map[range] = false;
  67 }
  68
  69 void FunctionHasExecutedCache::removeUnexecutedRange(intptr_t id, unsigned start, unsigned end)
  70 {
  71     // FIXME: We should never have an instance where we return here, but currently do in some situations. Find out why.
  72     if (m_rangeMap.find(id) == m_rangeMap.end())
  73         return;
  74
  75     RangeMap& map = m_rangeMap.find(id)->second;
  76
  77     FunctionRange range;
  78     range.m_start = start;
  79     range.m_end = end;
  80     map[range] = true;
  81 }
  82
  83 Vector<std::tuple<bool, unsigned, unsigned>> FunctionHasExecutedCache::getFunctionRanges(intptr_t id)
  84 {
  85     Vector<std::tuple<bool, unsigned, unsigned>> ranges(0);
  86     auto findResult = m_rangeMap.find(id);
  87     if (findResult == m_rangeMap.end())
  88         return ranges;
  89
  90     RangeMap& map = m_rangeMap.find(id)->second;
  91     for (auto iter = map.begin(), end = map.end(); iter != end; ++iter) {
  92         const FunctionRange& range = iter->first;
  93         bool hasExecuted = iter->second;
  94         ranges.append(std::tuple<bool, unsigned, unsigned>(hasExecuted, range.m_start, range.m_end));
  95     }
  96
  97     return ranges;
  98 }
  99
 100 } // namespace JSC