Oilpan: introduce sticky forcedForTesting flag to ensure that a precise

Source/heap/ThreadState.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 217 matching lines @@
 
 ThreadState::ThreadState()
     : m_thread(currentThread())
     , m_persistents(adoptPtr(new PersistentAnchor()))
     , m_startOfStack(reinterpret_cast<intptr_t*>(getStackStart()))
     , m_endOfStack(reinterpret_cast<intptr_t*>(getStackStart()))
     , m_safePointScopeMarker(0)
     , m_atSafePoint(false)
     , m_interruptors()
     , m_gcRequested(false)
+    , m_forcedForTesting(false)
     , m_sweepRequested(0)
     , m_sweepInProgress(false)
     , m_noAllocationCount(0)
     , m_inGC(false)
     , m_heapContainsCache(adoptPtr(new HeapContainsCache()))
     , m_isCleaningUp(false)
 {
     ASSERT(!**s_threadSpecific);
     **s_threadSpecific = this;
 
@@ skipping 242 matching lines @@
     checkThread();
     m_gcRequested = true;
 }
 
 void ThreadState::clearGCRequested()
 {
     checkThread();
     m_gcRequested = false;
 }
 
+void ThreadState::performPendingGC(StackState stackState)
+{
+    if (stackState == NoHeapPointersOnStack && (gcRequested() || forcedForTesting())) {
+        setForcedForTesting(false);
+        Heap::collectGarbage(NoHeapPointersOnStack);
+    }
+}
+
+void ThreadState::setForcedForTesting(bool value)
+{
+    checkThread();
+    m_forcedForTesting = value;
+}
+
+bool ThreadState::forcedForTesting()
+{
+    checkThread();
+    return m_forcedForTesting;
+}
+
 bool ThreadState::isConsistentForGC()
 {
     for (int i = 0; i < NumberOfHeaps; i++) {
         if (!m_heaps[i]->isConsistentForGC())
             return false;
     }
     return true;
 }
 
 void ThreadState::makeConsistentForGC()
@@ skipping 72 matching lines @@
 }
 
 void ThreadState::resumeThreads()
 {
     s_safePointBarrier->resumeOthers();
 }
 
 void ThreadState::safePoint(StackState stackState)
 {
     checkThread();
-    if (stackState == NoHeapPointersOnStack && gcRequested())
-        Heap::collectGarbage(NoHeapPointersOnStack);
+    performPendingGC(stackState);
     m_stackState = stackState;
     s_safePointBarrier->checkAndPark(this);
     m_stackState = HeapPointersOnStack;
 }
 
 #ifdef ADDRESS_SANITIZER
 // When we are running under AddressSanitizer with detect_stack_use_after_return=1
 // then stack marker obtained from SafePointScope will point into a fake stack.
 // Detect this case by checking if it falls in between current stack frame
 // and stack start and use an arbitrary high enough value for it.
@@ skipping 17 matching lines @@
 }
 #endif
 
 void ThreadState::enterSafePoint(StackState stackState, void* scopeMarker)
 {
 #ifdef ADDRESS_SANITIZER
     if (stackState == HeapPointersOnStack)
         scopeMarker = adjustScopeMarkerForAdressSanitizer(scopeMarker);
 #endif
     ASSERT(stackState == NoHeapPointersOnStack || scopeMarker);
-    if (stackState == NoHeapPointersOnStack && gcRequested())
-        Heap::collectGarbage(NoHeapPointersOnStack);
+    performPendingGC(stackState);
     checkThread();
     ASSERT(!m_atSafePoint);
     m_atSafePoint = true;
     m_stackState = stackState;
     m_safePointScopeMarker = scopeMarker;
     s_safePointBarrier->enterSafePoint(this);
 }
 
 void ThreadState::leaveSafePoint()
 {
@@ skipping 75 matching lines @@
     state->safePoint(HeapPointersOnStack);
 }
 
 ThreadState::AttachedThreadStateSet& ThreadState::attachedThreads()
 {
     DEFINE_STATIC_LOCAL(AttachedThreadStateSet, threads, ());
     return threads;
 }
 
 }