1  /*
 2   * Copyright (C) 2018 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  #pragma once
27  
28  #include "BytecodeIndex.h"
29  #include "ExitFlag.h"
30  
31  namespace JSC {
32  
33  class CodeBlock;
34  class StructureSet;
35  
36  template<typename VariantVectorType, typename VariantType>
37  bool appendICStatusVariant(VariantVectorType& variants, const VariantType& variant)
38  {
39      // Attempt to merge this variant with an already existing variant.
40      for (unsigned i = 0; i < variants.size(); ++i) {
41          VariantType& mergedVariant = variants[i];
42          if (mergedVariant.attemptToMerge(variant)) {
43              for (unsigned j = 0; j < variants.size(); ++j) {
44                  if (i == j)
45                      continue;
46                  if (variants[j].overlaps(mergedVariant))
47                      return false;
48              }
49              return true;
50          }
51      }
52      
53      // Make sure there is no overlap. We should have pruned out opportunities for
54      // overlap but it's possible that an inline cache got into a weird state. We are
55      // defensive and bail if we detect crazy.
56      for (unsigned i = 0; i < variants.size(); ++i) {
57          if (variants[i].overlaps(variant))
58              return false;
59      }
60      
61      variants.append(variant);
62      return true;
63  }
64  
65  template<typename VariantVectorType>
66  void filterICStatusVariants(VariantVectorType& variants, const StructureSet& set)
67  {
68      variants.removeAllMatching(
69          [&] (auto& variant) -> bool {
70              variant.structureSet().filter(set);
71              return variant.structureSet().isEmpty();
72          });
73  }
74  
75  ExitFlag hasBadCacheExitSite(CodeBlock* profiledBlock, BytecodeIndex);
76  
77  } // namespace JSC
78