bytecode/CallLinkInfo.cpp

   1 /*
   2  * Copyright (C) 2012, 2013, 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 "CallLinkInfo.h"
  28
  29 #include "DFGOperations.h"
  30 #include "DFGThunks.h"
  31 #include "JSCInlines.h"
  32 #include "Repatch.h"
  33 #include "RepatchBuffer.h"
  34 #include <wtf/ListDump.h>
  35 #include <wtf/NeverDestroyed.h>
  36
  37 #if ENABLE(JIT)
  38 namespace JSC {
  39
  40 void CallLinkInfo::clearStub()
  41 {
  42     if (!stub())
  43         return;
  44
  45     m_stub->clearCallNodesFor(this);
  46     m_stub = nullptr;
  47 }
  48
  49 void CallLinkInfo::unlink(RepatchBuffer& repatchBuffer)
  50 {
  51     if (!isLinked()) {
  52         // We could be called even if we're not linked anymore because of how polymorphic calls
  53         // work. Each callsite within the polymorphic call stub may separately ask us to unlink().
  54         RELEASE_ASSERT(!isOnList());
  55         return;
  56     }
  57
  58     unlinkFor(
  59         repatchBuffer, *this,
  60         (m_callType == Construct || m_callType == ConstructVarargs)? CodeForConstruct : CodeForCall,
  61         m_isFTL ? MustPreserveRegisters : RegisterPreservationNotRequired);
  62
  63     // It will be on a list if the callee has a code block.
  64     if (isOnList())
  65         remove();
  66 }
  67
  68 void CallLinkInfo::visitWeak(RepatchBuffer& repatchBuffer)
  69 {
  70     auto handleSpecificCallee = [&] (JSFunction* callee) {
  71         if (Heap::isMarked(callee->executable()))
  72             m_hasSeenClosure = true;
  73         else
  74             m_clearedByGC = true;
  75     };
  76
  77     if (isLinked()) {
  78         if (stub()) {
  79             if (!stub()->visitWeak(repatchBuffer)) {
  80                 if (Options::verboseOSR()) {
  81                     dataLog(
  82                         "Clearing closure call from ", *repatchBuffer.codeBlock(), " to ",
  83                         listDump(stub()->variants()), ", stub routine ", RawPointer(stub()),
  84                         ".\n");
  85                 }
  86                 unlink(repatchBuffer);
  87                 m_clearedByGC = true;
  88             }
  89         } else if (!Heap::isMarked(m_callee.get())) {
  90             if (Options::verboseOSR()) {
  91                 dataLog(
  92                     "Clearing call from ", *repatchBuffer.codeBlock(), " to ",
  93                     RawPointer(m_callee.get()), " (",
  94                     m_callee.get()->executable()->hashFor(specializationKind()),
  95                     ").\n");
  96             }
  97             handleSpecificCallee(m_callee.get());
  98             unlink(repatchBuffer);
  99         }
 100     }
 101     if (haveLastSeenCallee() && !Heap::isMarked(lastSeenCallee())) {
 102         handleSpecificCallee(lastSeenCallee());
 103         clearLastSeenCallee();
 104     }
 105 }
 106
 107 CallLinkInfo& CallLinkInfo::dummy()
 108 {
 109     static NeverDestroyed<CallLinkInfo> dummy;
 110     return dummy;
 111 }
 112
 113 } // namespace JSC
 114 #endif // ENABLE(JIT)
 115