jit/GCAwareJITStubRoutine.cpp

   1 /*
   2  * Copyright (C) 2012 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 "GCAwareJITStubRoutine.h"
  28
  29 #if ENABLE(JIT)
  30
  31 #include "Heap.h"
  32 #include "VM.h"
  33 #include "JSCInlines.h"
  34 #include "SlotVisitor.h"
  35 #include "Structure.h"
  36
  37 namespace JSC {
  38
  39 GCAwareJITStubRoutine::GCAwareJITStubRoutine(
  40     const MacroAssemblerCodeRef& code, VM& vm)
  41     : JITStubRoutine(code)
  42     , m_mayBeExecuting(false)
  43     , m_isJettisoned(false)
  44 {
  45     vm.heap.m_jitStubRoutines.add(this);
  46 }
  47
  48 GCAwareJITStubRoutine::~GCAwareJITStubRoutine() { }
  49
  50 void GCAwareJITStubRoutine::observeZeroRefCount()
  51 {
  52     if (m_isJettisoned) {
  53         // This case is needed for when the system shuts down. It may be that
  54         // the JIT stub routine set gets deleted before we get around to deleting
  55         // this guy. In that case the GC informs us that we're jettisoned already
  56         // and that we should delete ourselves as soon as the ref count reaches
  57         // zero.
  58         delete this;
  59         return;
  60     }
  61
  62     RELEASE_ASSERT(!m_refCount);
  63
  64     m_isJettisoned = true;
  65 }
  66
  67 void GCAwareJITStubRoutine::deleteFromGC()
  68 {
  69     ASSERT(m_isJettisoned);
  70     ASSERT(!m_refCount);
  71     ASSERT(!m_mayBeExecuting);
  72
  73     delete this;
  74 }
  75
  76 void GCAwareJITStubRoutine::markRequiredObjectsInternal(SlotVisitor&)
  77 {
  78 }
  79
  80 MarkingGCAwareJITStubRoutineWithOneObject::MarkingGCAwareJITStubRoutineWithOneObject(
  81     const MacroAssemblerCodeRef& code, VM& vm, const JSCell* owner,
  82     JSCell* object)
  83     : GCAwareJITStubRoutine(code, vm)
  84     , m_object(vm, owner, object)
  85 {
  86 }
  87
  88 MarkingGCAwareJITStubRoutineWithOneObject::~MarkingGCAwareJITStubRoutineWithOneObject()
  89 {
  90 }
  91
  92 void MarkingGCAwareJITStubRoutineWithOneObject::markRequiredObjectsInternal(SlotVisitor& visitor)
  93 {
  94     visitor.append(&m_object);
  95 }
  96
  97 PassRefPtr<JITStubRoutine> createJITStubRoutine(
  98     const MacroAssemblerCodeRef& code,
  99     VM& vm,
 100     const JSCell* owner,
 101     bool makesCalls,
 102     JSCell* object)
 103 {
 104     if (!makesCalls)
 105         return adoptRef(new JITStubRoutine(code));
 106
 107     if (!object) {
 108         return static_pointer_cast<JITStubRoutine>(
 109             adoptRef(new GCAwareJITStubRoutine(code, vm)));
 110     }
 111
 112     return static_pointer_cast<JITStubRoutine>(
 113         adoptRef(new MarkingGCAwareJITStubRoutineWithOneObject(code, vm, owner, object)));
 114 }
 115
 116 } // namespace JSC
 117
 118 #endif // ENABLE(JIT)
 119