runtime/ControlFlowProfiler.h

   1 /*
   2  * Copyright (C) 2014 Apple Inc. All rights reserved.
   3  * Copyright (C) 2014 Saam Barati. <saambarati1@gmail.com>
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
  15  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  17  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
  18  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  19  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  20  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  21  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  22  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  24  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25  */
  26
  27 #ifndef ControlFlowProfiler_h
  28 #define ControlFlowProfiler_h
  29
  30 #include "BasicBlockLocation.h"
  31 #include <wtf/HashMap.h>
  32 #include <wtf/HashMethod.h>
  33
  34 namespace JSC {
  35
  36 class VM;
  37
  38 struct BasicBlockKey {
  39     BasicBlockKey()
  40         : m_startOffset(-3)
  41         , m_endOffset(-3)
  42     { }
  43
  44     BasicBlockKey(int startOffset, int endOffset)
  45         : m_startOffset(startOffset)
  46         , m_endOffset(endOffset)
  47     { }
  48
  49     BasicBlockKey(WTF::HashTableDeletedValueType)
  50         : m_startOffset(-2)
  51         , m_endOffset(-2)
  52     { }
  53
  54     bool isHashTableDeletedValue() const { return m_startOffset == -2 && m_endOffset == -2; }
  55     bool operator==(const BasicBlockKey& other) const { return m_startOffset == other.m_startOffset && m_endOffset == other.m_endOffset; }
  56     unsigned hash() const { return m_startOffset + m_endOffset + 1; }
  57
  58     int m_startOffset;
  59     int m_endOffset;
  60 };
  61
  62 struct BasicBlockKeyHash {
  63     static unsigned hash(const BasicBlockKey& key) { return key.hash(); }
  64     static bool equal(const BasicBlockKey& a, const BasicBlockKey& b) { return a == b; }
  65     static const bool safeToCompareToEmptyOrDeleted = true;
  66 };
  67
  68 } // namespace JSC
  69
  70 namespace WTF {
  71
  72 template<typename T> struct DefaultHash;
  73 template<> struct DefaultHash<JSC::BasicBlockKey> {
  74     typedef JSC::BasicBlockKeyHash Hash;
  75 };
  76
  77 template<typename T> struct HashTraits;
  78 template<> struct HashTraits<JSC::BasicBlockKey> : SimpleClassHashTraits<JSC::BasicBlockKey> {
  79     static const bool emptyValueIsZero = false;
  80 };
  81
  82 } // namespace WTF
  83
  84 namespace JSC {
  85
  86 struct BasicBlockRange {
  87     int m_startOffset;
  88     int m_endOffset;
  89     bool m_hasExecuted;
  90 };
  91
  92 class ControlFlowProfiler {
  93 public:
  94     ControlFlowProfiler();
  95     ~ControlFlowProfiler();
  96     BasicBlockLocation* getBasicBlockLocation(intptr_t sourceID, int startOffset, int endOffset);
  97     JS_EXPORT_PRIVATE void dumpData() const;
  98     Vector<BasicBlockRange> getBasicBlocksForSourceID(intptr_t sourceID, VM&) const;
  99     BasicBlockLocation* dummyBasicBlock() { return &m_dummyBasicBlock; }
 100     JS_EXPORT_PRIVATE bool hasBasicBlockAtTextOffsetBeenExecuted(int, intptr_t, VM&); // This function exists for testing.
 101
 102 private:
 103     typedef HashMap<BasicBlockKey, BasicBlockLocation*> BlockLocationCache;
 104     typedef HashMap<intptr_t, BlockLocationCache> SourceIDBuckets;
 105
 106     SourceIDBuckets m_sourceIDBuckets;
 107     BasicBlockLocation m_dummyBasicBlock;
 108 };
 109
 110 } // namespace JSC
 111
 112 #endif // ControlFlowProfiler_h