bytecode/ConstantStructureCheck.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 "ConstantStructureCheck.h"
  28
  29 #include "JSCInlines.h"
  30
  31 namespace JSC {
  32
  33 void ConstantStructureCheck::dumpInContext(PrintStream& out, DumpContext* context) const
  34 {
  35     out.print(
  36         "(Check if ", inContext(JSValue(m_constant), context), " has structure ",
  37         pointerDumpInContext(m_structure, context), ")");
  38 }
  39
  40 void ConstantStructureCheck::dump(PrintStream& out) const
  41 {
  42     dumpInContext(out, nullptr);
  43 }
  44
  45 Structure* structureFor(const ConstantStructureCheckVector& vector, JSCell* constant)
  46 {
  47     for (unsigned i = vector.size(); i--;) {
  48         if (vector[i].constant() == constant)
  49             return vector[i].structure();
  50     }
  51     return nullptr;
  52 }
  53
  54 bool areCompatible(const ConstantStructureCheckVector& a, const ConstantStructureCheckVector& b)
  55 {
  56     for (unsigned i = a.size(); i--;) {
  57         Structure* otherStructure = structureFor(b, a[i].constant());
  58         if (!otherStructure)
  59             continue;
  60         if (a[i].structure() != otherStructure)
  61             return false;
  62     }
  63     return true;
  64 }
  65
  66 void mergeInto(const ConstantStructureCheckVector& source, ConstantStructureCheckVector& target)
  67 {
  68     for (unsigned i = source.size(); i--;) {
  69         if (structureFor(target, source[i].constant()))
  70             continue;
  71         target.append(source[i]);
  72     }
  73 }
  74
  75 } // namespace JSC
  76