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<dl class="meta">
<dt>Revision</dt> <dd><a href="http://trac.webkit.org/projects/webkit/changeset/210634">210634</a></dd>
<dt>Author</dt> <dd>matthew_hanson@apple.com</dd>
<dt>Date</dt> <dd>2017-01-12 08:44:41 -0800 (Thu, 12 Jan 2017)</dd>
</dl>

<h3>Log Message</h3>
<pre>Merge <a href="http://trac.webkit.org/projects/webkit/changeset/210451">r210451</a>. rdar://problem/29909812</pre>

<h3>Modified Paths</h3>
<ul>
<li><a href="#branchessafari603branchJSTestsChangeLog">branches/safari-603-branch/JSTests/ChangeLog</a></li>
<li><a href="#branchessafari603branchJSTestsstressslowpathgeneratorupdatingcurrentnodedfgjs">branches/safari-603-branch/JSTests/stress/slow-path-generator-updating-current-node-dfg.js</a></li>
<li><a href="#branchessafari603branchJSTestsstressunshiftarraystoragejs">branches/safari-603-branch/JSTests/stress/unshift-array-storage.js</a></li>
<li><a href="#branchessafari603branchSourceJavaScriptCoreChangeLog">branches/safari-603-branch/Source/JavaScriptCore/ChangeLog</a></li>
<li><a href="#branchessafari603branchSourceJavaScriptCoreheapHeapcpp">branches/safari-603-branch/Source/JavaScriptCore/heap/Heap.cpp</a></li>
<li><a href="#branchessafari603branchSourceJavaScriptCoreheapHeaph">branches/safari-603-branch/Source/JavaScriptCore/heap/Heap.h</a></li>
<li><a href="#branchessafari603branchSourceJavaScriptCoreheapHeapInlinesh">branches/safari-603-branch/Source/JavaScriptCore/heap/HeapInlines.h</a></li>
<li><a href="#branchessafari603branchSourceJavaScriptCoreruntimeOptionscpp">branches/safari-603-branch/Source/JavaScriptCore/runtime/Options.cpp</a></li>
<li><a href="#branchessafari603branchSourceJavaScriptCoreruntimeOptionsh">branches/safari-603-branch/Source/JavaScriptCore/runtime/Options.h</a></li>
<li><a href="#branchessafari603branchSourceJavaScriptCoreruntimeScriptExecutablecpp">branches/safari-603-branch/Source/JavaScriptCore/runtime/ScriptExecutable.cpp</a></li>
</ul>

</div>
<div id="patch">
<h3>Diff</h3>
<a id="branchessafari603branchJSTestsChangeLog"></a>
<div class="modfile"><h4>Modified: branches/safari-603-branch/JSTests/ChangeLog (210633 => 210634)</h4>
<pre class="diff"><span>
<span class="info">--- branches/safari-603-branch/JSTests/ChangeLog        2017-01-12 16:44:36 UTC (rev 210633)
+++ branches/safari-603-branch/JSTests/ChangeLog        2017-01-12 16:44:41 UTC (rev 210634)
</span><span class="lines">@@ -1,3 +1,17 @@
</span><ins>+2017-01-11  Matthew Hanson  &lt;matthew_hanson@apple.com&gt;
+
+        Merge r210451. rdar://problem/29909812
+
+    2016-12-30  Filip Pizlo  &lt;fpizlo@apple.com&gt;
+
+            DeferGC::~DeferGC should be super cheap
+            https://bugs.webkit.org/show_bug.cgi?id=166626
+
+            Reviewed by Saam Barati.
+
+            * stress/slow-path-generator-updating-current-node-dfg.js:
+            * stress/unshift-array-storage.js:
+
</ins><span class="cx"> 2017-01-10  Matthew Hanson  &lt;matthew_hanson@apple.com&gt;
</span><span class="cx"> 
</span><span class="cx">         Rollout r210336. rdar://problem/29912353
</span></span></pre></div>
<a id="branchessafari603branchJSTestsstressslowpathgeneratorupdatingcurrentnodedfgjs"></a>
<div class="modfile"><h4>Modified: branches/safari-603-branch/JSTests/stress/slow-path-generator-updating-current-node-dfg.js (210633 => 210634)</h4>
<pre class="diff"><span>
<span class="info">--- branches/safari-603-branch/JSTests/stress/slow-path-generator-updating-current-node-dfg.js        2017-01-12 16:44:36 UTC (rev 210633)
+++ branches/safari-603-branch/JSTests/stress/slow-path-generator-updating-current-node-dfg.js        2017-01-12 16:44:41 UTC (rev 210634)
</span><span class="lines">@@ -1,4 +1,7 @@
</span><del>-//@ runFTLNoCJIT(&quot;--deferGCShouldCollectWithProbability=true&quot;, &quot;--deferGCProbability=1.0&quot;)
</del><ins>+// FIXME: Bring back something like the deferGC probability mode.
+// https://bugs.webkit.org/show_bug.cgi?id=166627
+//@ skip
+// //@ runFTLNoCJIT(&quot;--deferGCShouldCollectWithProbability=true&quot;, &quot;--deferGCProbability=1.0&quot;)
</ins><span class="cx"> 
</span><span class="cx"> function foo(a) {
</span><span class="cx">     return a.push(25);
</span></span></pre></div>
<a id="branchessafari603branchJSTestsstressunshiftarraystoragejs"></a>
<div class="modfile"><h4>Modified: branches/safari-603-branch/JSTests/stress/unshift-array-storage.js (210633 => 210634)</h4>
<pre class="diff"><span>
<span class="info">--- branches/safari-603-branch/JSTests/stress/unshift-array-storage.js        2017-01-12 16:44:36 UTC (rev 210633)
+++ branches/safari-603-branch/JSTests/stress/unshift-array-storage.js        2017-01-12 16:44:41 UTC (rev 210634)
</span><span class="lines">@@ -1,4 +1,7 @@
</span><del>-//@ runFTLNoCJIT(&quot;--scribbleFreeCells=true&quot;, &quot;--deferGCShouldCollectWithProbability=true&quot;, &quot;--deferGCProbability=1&quot;)
</del><ins>+// FIXME: Bring back something like the deferGC probability mode.
+// https://bugs.webkit.org/show_bug.cgi?id=166627
+//@ skip
+// //@ runFTLNoCJIT(&quot;--scribbleFreeCells=true&quot;, &quot;--deferGCShouldCollectWithProbability=true&quot;, &quot;--deferGCProbability=1&quot;)
</ins><span class="cx"> 
</span><span class="cx"> // Create some array storage.
</span><span class="cx"> var array = [];
</span></span></pre></div>
<a id="branchessafari603branchSourceJavaScriptCoreChangeLog"></a>
<div class="modfile"><h4>Modified: branches/safari-603-branch/Source/JavaScriptCore/ChangeLog (210633 => 210634)</h4>
<pre class="diff"><span>
<span class="info">--- branches/safari-603-branch/Source/JavaScriptCore/ChangeLog        2017-01-12 16:44:36 UTC (rev 210633)
+++ branches/safari-603-branch/Source/JavaScriptCore/ChangeLog        2017-01-12 16:44:41 UTC (rev 210634)
</span><span class="lines">@@ -1,5 +1,52 @@
</span><span class="cx"> 2017-01-11  Matthew Hanson  &lt;matthew_hanson@apple.com&gt;
</span><span class="cx"> 
</span><ins>+        Merge r210451. rdar://problem/29909812
+
+    2016-12-30  Filip Pizlo  &lt;fpizlo@apple.com&gt;
+
+            DeferGC::~DeferGC should be super cheap
+            https://bugs.webkit.org/show_bug.cgi?id=166626
+
+            Reviewed by Saam Barati.
+
+            Right now, ~DeferGC requires running the collector's full collectIfNecessaryOrDefer()
+            hook, which is super big. Normally, that hook would only be called from GC slow paths,
+            so it ought to be possible to add complex logic to it. It benefits the GC algorithm to
+            make that code smart, not necessarily fast.
+
+            The right thing for it to do is to have ~DeferGC check a boolean to see if
+            collectIfNecessaryOrDefer() had previously deferred anything, and only call it if that
+            is true. That's what this patch does.
+
+            Unfortunately, this means that we lose the collectAccordingToDeferGCProbability mode,
+            which we used for two tests. Since I could only see two tests that used this mode, I
+            felt that it was better to enhance the GC than to keep the tests. I filed bug 166627 to
+            bring back something like that mode.
+
+            Although this patch does make some paths faster, its real goal is to ensure that bug
+            165963 can add more logic to collectIfNecessaryOrDefer() without introducing a big
+            regression. Until then, I wouldn't be surprised if this patch was a progression, but I'm
+            not betting on it.
+
+            * heap/Heap.cpp:
+            (JSC::Heap::collectIfNecessaryOrDefer):
+            (JSC::Heap::decrementDeferralDepthAndGCIfNeededSlow):
+            (JSC::Heap::canCollect): Deleted.
+            (JSC::Heap::shouldCollectHeuristic): Deleted.
+            (JSC::Heap::shouldCollect): Deleted.
+            (JSC::Heap::collectAccordingToDeferGCProbability): Deleted.
+            (JSC::Heap::decrementDeferralDepthAndGCIfNeeded): Deleted.
+            * heap/Heap.h:
+            * heap/HeapInlines.h:
+            (JSC::Heap::incrementDeferralDepth):
+            (JSC::Heap::decrementDeferralDepth):
+            (JSC::Heap::decrementDeferralDepthAndGCIfNeeded):
+            (JSC::Heap::mayNeedToStop):
+            (JSC::Heap::stopIfNecessary):
+            * runtime/Options.h:
+
+2017-01-11  Matthew Hanson  &lt;matthew_hanson@apple.com&gt;
+
</ins><span class="cx">         Merge r210398. rdar://problem/29229439
</span><span class="cx"> 
</span><span class="cx">     2017-01-05  Filip Pizlo  &lt;fpizlo@apple.com&gt;
</span></span></pre></div>
<a id="branchessafari603branchSourceJavaScriptCoreheapHeapcpp"></a>
<div class="modfile"><h4>Modified: branches/safari-603-branch/Source/JavaScriptCore/heap/Heap.cpp (210633 => 210634)</h4>
<pre class="diff"><span>
<span class="info">--- branches/safari-603-branch/Source/JavaScriptCore/heap/Heap.cpp        2017-01-12 16:44:36 UTC (rev 210633)
+++ branches/safari-603-branch/Source/JavaScriptCore/heap/Heap.cpp        2017-01-12 16:44:41 UTC (rev 210634)
</span><span class="lines">@@ -1,5 +1,5 @@
</span><span class="cx"> /*
</span><del>- *  Copyright (C) 2003-2009, 2011, 2013-2016 Apple Inc. All rights reserved.
</del><ins>+ *  Copyright (C) 2003-2017 Apple Inc. All rights reserved.
</ins><span class="cx">  *  Copyright (C) 2007 Eric Seidel &lt;eric@webkit.org&gt;
</span><span class="cx">  *
</span><span class="cx">  *  This library is free software; you can redistribute it and/or
</span><span class="lines">@@ -2023,29 +2023,6 @@
</span><span class="cx">     addToRememberedSet(from);
</span><span class="cx"> }
</span><span class="cx"> 
</span><del>-bool Heap::canCollect()
-{
-    if (isDeferred())
-        return false;
-    if (!m_isSafeToCollect)
-        return false;
-    if (mutatorState() == MutatorState::HelpingGC)
-        return false;
-    return true;
-}
-
-bool Heap::shouldCollectHeuristic()
-{
-    if (Options::gcMaxHeapSize())
-        return m_bytesAllocatedThisCycle &gt; Options::gcMaxHeapSize();
-    return m_bytesAllocatedThisCycle &gt; m_maxEdenSize;
-}
-
-bool Heap::shouldCollect()
-{
-    return canCollect() &amp;&amp; shouldCollectHeuristic();
-}
-
</del><span class="cx"> bool Heap::isCurrentThreadBusy()
</span><span class="cx"> {
</span><span class="cx">     return mayBeGCThread() || mutatorState() != MutatorState::Running;
</span><span class="lines">@@ -2077,49 +2054,55 @@
</span><span class="cx"> 
</span><span class="cx"> bool Heap::collectIfNecessaryOrDefer(GCDeferralContext* deferralContext)
</span><span class="cx"> {
</span><del>-    if (!canCollect())
</del><ins>+    ASSERT(!DisallowGC::isGCDisallowedOnCurrentThread());
+
+    if (!m_isSafeToCollect)
</ins><span class="cx">         return false;
</span><ins>+    if (mutatorState() == MutatorState::HelpingGC)
+        return false;
+    if (!Options::useGC())
+        return false;
</ins><span class="cx">     
</span><del>-    if (deferralContext) {
-        deferralContext-&gt;m_shouldGC |=
-            !!(m_worldState.load() &amp; (shouldStopBit | needFinalizeBit | gcDidJITBit));
-    } else
-        stopIfNecessary();
</del><ins>+    if (mayNeedToStop()) {
+        if (deferralContext)
+            deferralContext-&gt;m_shouldGC = true;
+        else if (isDeferred())
+            m_didDeferGCWork = true;
+        else
+            stopIfNecessary();
+    }
</ins><span class="cx">     
</span><del>-    if (!shouldCollectHeuristic())
-        return false;
</del><ins>+    if (UNLIKELY(Options::gcMaxHeapSize())) {
+        if (m_bytesAllocatedThisCycle &lt;= Options::gcMaxHeapSize())
+            return false;
+    } else {
+        if (m_bytesAllocatedThisCycle &lt;= m_maxEdenSize)
+            return false;
+    }
</ins><span class="cx"> 
</span><span class="cx">     if (deferralContext)
</span><span class="cx">         deferralContext-&gt;m_shouldGC = true;
</span><ins>+    else if (isDeferred())
+        m_didDeferGCWork = true;
</ins><span class="cx">     else
</span><span class="cx">         collectAsync();
</span><span class="cx">     return true;
</span><span class="cx"> }
</span><span class="cx"> 
</span><del>-void Heap::collectAccordingToDeferGCProbability()
</del><ins>+void Heap::decrementDeferralDepthAndGCIfNeededSlow()
</ins><span class="cx"> {
</span><del>-    if (isDeferred() || !m_isSafeToCollect || collectionScope() || mutatorState() == MutatorState::HelpingGC)
</del><ins>+    // Can't do anything if we're still deferred.
+    if (m_deferralDepth)
</ins><span class="cx">         return;
</span><del>-
-    if (randomNumber() &lt; Options::deferGCProbability()) {
-        collectAsync();
-        return;
-    }
-
-    // If our coin flip told us not to GC, we still might GC,
-    // but we GC according to our memory pressure markers.
</del><ins>+    
+    ASSERT(!isDeferred());
+    
+    m_didDeferGCWork = false;
+    // FIXME: Bring back something like the DeferGCProbability mode.
+    // https://bugs.webkit.org/show_bug.cgi?id=166627
</ins><span class="cx">     collectIfNecessaryOrDefer();
</span><span class="cx"> }
</span><span class="cx"> 
</span><del>-void Heap::decrementDeferralDepthAndGCIfNeeded()
-{
-    decrementDeferralDepth();
-    if (UNLIKELY(Options::deferGCShouldCollectWithProbability()))
-        collectAccordingToDeferGCProbability();
-    else
-        collectIfNecessaryOrDefer();
-}
-
</del><span class="cx"> void Heap::registerWeakGCMap(void* weakGCMap, std::function&lt;void()&gt; pruningCallback)
</span><span class="cx"> {
</span><span class="cx">     m_weakGCMaps.add(weakGCMap, WTFMove(pruningCallback));
</span></span></pre></div>
<a id="branchessafari603branchSourceJavaScriptCoreheapHeaph"></a>
<div class="modfile"><h4>Modified: branches/safari-603-branch/Source/JavaScriptCore/heap/Heap.h (210633 => 210634)</h4>
<pre class="diff"><span>
<span class="info">--- branches/safari-603-branch/Source/JavaScriptCore/heap/Heap.h        2017-01-12 16:44:36 UTC (rev 210633)
+++ branches/safari-603-branch/Source/JavaScriptCore/heap/Heap.h        2017-01-12 16:44:41 UTC (rev 210634)
</span><span class="lines">@@ -1,7 +1,7 @@
</span><span class="cx"> /*
</span><span class="cx">  *  Copyright (C) 1999-2000 Harri Porten (porten@kde.org)
</span><span class="cx">  *  Copyright (C) 2001 Peter Kelly (pmk@post.com)
</span><del>- *  Copyright (C) 2003-2009, 2013-2016 Apple Inc. All rights reserved.
</del><ins>+ *  Copyright (C) 2003-2017 Apple Inc. All rights reserved.
</ins><span class="cx">  *
</span><span class="cx">  *  This library is free software; you can redistribute it and/or
</span><span class="cx">  *  modify it under the terms of the GNU Lesser General Public
</span><span class="lines">@@ -185,9 +185,7 @@
</span><span class="cx">     JS_EXPORT_PRIVATE void collectAllGarbageIfNotDoneRecently();
</span><span class="cx">     JS_EXPORT_PRIVATE void collectAllGarbage();
</span><span class="cx"> 
</span><del>-    bool canCollect();
</del><span class="cx">     bool shouldCollectHeuristic();
</span><del>-    bool shouldCollect();
</del><span class="cx">     
</span><span class="cx">     // Queue up a collection. Returns immediately. This will not queue a collection if a collection
</span><span class="cx">     // of equal or greater strength exists. Full collections are stronger than std::nullopt collections
</span><span class="lines">@@ -204,7 +202,6 @@
</span><span class="cx">     JS_EXPORT_PRIVATE void collectSync(std::optional&lt;CollectionScope&gt; = std::nullopt);
</span><span class="cx">     
</span><span class="cx">     bool collectIfNecessaryOrDefer(GCDeferralContext* = nullptr); // Returns true if it did collect.
</span><del>-    void collectAccordingToDeferGCProbability();
</del><span class="cx"> 
</span><span class="cx">     void completeAllJITPlans();
</span><span class="cx">     
</span><span class="lines">@@ -268,7 +265,7 @@
</span><span class="cx">     
</span><span class="cx">     void addReference(JSCell*, ArrayBuffer*);
</span><span class="cx">     
</span><del>-    bool isDeferred() const { return !!m_deferralDepth || !Options::useGC(); }
</del><ins>+    bool isDeferred() const { return !!m_deferralDepth; }
</ins><span class="cx"> 
</span><span class="cx">     StructureIDTable&amp; structureIDTable() { return m_structureIDTable; }
</span><span class="cx"> 
</span><span class="lines">@@ -341,6 +338,8 @@
</span><span class="cx">     // already be called for you at the right times.
</span><span class="cx">     void stopIfNecessary();
</span><span class="cx">     
</span><ins>+    bool mayNeedToStop();
+    
</ins><span class="cx">     // This is a much stronger kind of stopping of the collector, and it may require waiting for a
</span><span class="cx">     // while. This is meant to be a legacy API for clients of collectAllGarbage that expect that there
</span><span class="cx">     // is no GC before or after that function call. After calling this, you are free to start GCs
</span><span class="lines">@@ -488,7 +487,8 @@
</span><span class="cx"> 
</span><span class="cx">     void incrementDeferralDepth();
</span><span class="cx">     void decrementDeferralDepth();
</span><del>-    JS_EXPORT_PRIVATE void decrementDeferralDepthAndGCIfNeeded();
</del><ins>+    void decrementDeferralDepthAndGCIfNeeded();
+    JS_EXPORT_PRIVATE void decrementDeferralDepthAndGCIfNeededSlow();
</ins><span class="cx"> 
</span><span class="cx">     size_t threadVisitCount();
</span><span class="cx">     size_t threadBytesVisited();
</span><span class="lines">@@ -579,6 +579,7 @@
</span><span class="cx">     Vector&lt;HeapObserver*&gt; m_observers;
</span><span class="cx"> 
</span><span class="cx">     unsigned m_deferralDepth;
</span><ins>+    bool m_didDeferGCWork { false };
</ins><span class="cx"> 
</span><span class="cx">     std::unique_ptr&lt;HeapVerifier&gt; m_verifier;
</span><span class="cx"> 
</span></span></pre></div>
<a id="branchessafari603branchSourceJavaScriptCoreheapHeapInlinesh"></a>
<div class="modfile"><h4>Modified: branches/safari-603-branch/Source/JavaScriptCore/heap/HeapInlines.h (210633 => 210634)</h4>
<pre class="diff"><span>
<span class="info">--- branches/safari-603-branch/Source/JavaScriptCore/heap/HeapInlines.h        2017-01-12 16:44:36 UTC (rev 210633)
+++ branches/safari-603-branch/Source/JavaScriptCore/heap/HeapInlines.h        2017-01-12 16:44:41 UTC (rev 210634)
</span><span class="lines">@@ -1,5 +1,5 @@
</span><span class="cx"> /*
</span><del>- * Copyright (C) 2014-2016 Apple Inc. All rights reserved.
</del><ins>+ * Copyright (C) 2014-2017 Apple Inc. All rights reserved.
</ins><span class="cx">  *
</span><span class="cx">  * Redistribution and use in source and binary forms, with or without
</span><span class="cx">  * modification, are permitted provided that the following conditions
</span><span class="lines">@@ -315,16 +315,47 @@
</span><span class="cx"> 
</span><span class="cx"> inline void Heap::incrementDeferralDepth()
</span><span class="cx"> {
</span><del>-    RELEASE_ASSERT(m_deferralDepth &lt; 100); // Sanity check to make sure this doesn't get ridiculous.
</del><ins>+    ASSERT(!mayBeGCThread() || m_collectorBelievesThatTheWorldIsStopped);
</ins><span class="cx">     m_deferralDepth++;
</span><span class="cx"> }
</span><span class="cx"> 
</span><span class="cx"> inline void Heap::decrementDeferralDepth()
</span><span class="cx"> {
</span><del>-    RELEASE_ASSERT(m_deferralDepth &gt;= 1);
</del><ins>+    ASSERT(!mayBeGCThread() || m_collectorBelievesThatTheWorldIsStopped);
</ins><span class="cx">     m_deferralDepth--;
</span><span class="cx"> }
</span><span class="cx"> 
</span><ins>+inline void Heap::decrementDeferralDepthAndGCIfNeeded()
+{
+    ASSERT(!mayBeGCThread() || m_collectorBelievesThatTheWorldIsStopped);
+    m_deferralDepth--;
+    
+    if (UNLIKELY(m_didDeferGCWork)) {
+        decrementDeferralDepthAndGCIfNeededSlow();
+        
+        // Here are the possible relationships between m_deferralDepth and m_didDeferGCWork.
+        // Note that prior to the call to decrementDeferralDepthAndGCIfNeededSlow,
+        // m_didDeferGCWork had to have been true. Now it can be either false or true. There is
+        // nothing we can reliably assert.
+        //
+        // Possible arrangements of m_didDeferGCWork and !!m_deferralDepth:
+        //
+        // Both false: We popped out of all DeferGCs and we did whatever work was deferred.
+        //
+        // Only m_didDeferGCWork is true: We stopped for GC and the GC did DeferGC. This is
+        // possible because of how we handle the baseline JIT's worklist. It's also perfectly
+        // safe because it only protects reportExtraMemory. We can just ignore this.
+        //
+        // Only !!m_deferralDepth is true: m_didDeferGCWork had been set spuriously. It is only
+        // cleared by decrementDeferralDepthAndGCIfNeededSlow(). So, if we had deferred work but
+        // then decrementDeferralDepth()'d, then we might have the bit set even if we GC'd since
+        // then.
+        //
+        // Both true: We're in a recursive ~DeferGC. We wanted to do something about the
+        // deferred work, but were unable to.
+    }
+}
+
</ins><span class="cx"> inline HashSet&lt;MarkedArgumentBuffer*&gt;&amp; Heap::markListSet()
</span><span class="cx"> {
</span><span class="cx">     if (!m_markListSet)
</span><span class="lines">@@ -363,11 +394,15 @@
</span><span class="cx">     releaseAccessSlow();
</span><span class="cx"> }
</span><span class="cx"> 
</span><ins>+inline bool Heap::mayNeedToStop()
+{
+    return m_worldState.loadRelaxed() != hasAccessBit;
+}
+
</ins><span class="cx"> inline void Heap::stopIfNecessary()
</span><span class="cx"> {
</span><del>-    if (m_worldState.loadRelaxed() == hasAccessBit)
-        return;
-    stopIfNecessarySlow();
</del><ins>+    if (mayNeedToStop())
+        stopIfNecessarySlow();
</ins><span class="cx"> }
</span><span class="cx"> 
</span><span class="cx"> inline void Heap::writeBarrierOpaqueRoot(void* root)
</span></span></pre></div>
<a id="branchessafari603branchSourceJavaScriptCoreruntimeOptionscpp"></a>
<div class="modfile"><h4>Modified: branches/safari-603-branch/Source/JavaScriptCore/runtime/Options.cpp (210633 => 210634)</h4>
<pre class="diff"><span>
<span class="info">--- branches/safari-603-branch/Source/JavaScriptCore/runtime/Options.cpp        2017-01-12 16:44:36 UTC (rev 210633)
+++ branches/safari-603-branch/Source/JavaScriptCore/runtime/Options.cpp        2017-01-12 16:44:41 UTC (rev 210634)
</span><span class="lines">@@ -1,5 +1,5 @@
</span><span class="cx"> /*
</span><del>- * Copyright (C) 2011-2012, 2014-2016 Apple Inc. All rights reserved.
</del><ins>+ * Copyright (C) 2011-2017 Apple Inc. All rights reserved.
</ins><span class="cx">  *
</span><span class="cx">  * Redistribution and use in source and binary forms, with or without
</span><span class="cx">  * modification, are permitted provided that the following conditions
</span><span class="lines">@@ -418,7 +418,6 @@
</span><span class="cx"> 
</span><span class="cx">     ASSERT((static_cast&lt;int64_t&gt;(Options::thresholdForOptimizeAfterLongWarmUp()) &lt;&lt; Options::reoptimizationRetryCounterMax()) &gt; 0);
</span><span class="cx">     ASSERT((static_cast&lt;int64_t&gt;(Options::thresholdForOptimizeAfterLongWarmUp()) &lt;&lt; Options::reoptimizationRetryCounterMax()) &lt;= static_cast&lt;int64_t&gt;(std::numeric_limits&lt;int32_t&gt;::max()));
</span><del>-    ASSERT(Options::deferGCProbability() &gt;= 0.0 &amp;&amp; Options::deferGCProbability() &lt;= 1.0);
</del><span class="cx"> 
</span><span class="cx"> #if ENABLE(LLINT_STATS)
</span><span class="cx">     LLInt::Data::loadStats();
</span></span></pre></div>
<a id="branchessafari603branchSourceJavaScriptCoreruntimeOptionsh"></a>
<div class="modfile"><h4>Modified: branches/safari-603-branch/Source/JavaScriptCore/runtime/Options.h (210633 => 210634)</h4>
<pre class="diff"><span>
<span class="info">--- branches/safari-603-branch/Source/JavaScriptCore/runtime/Options.h        2017-01-12 16:44:36 UTC (rev 210633)
+++ branches/safari-603-branch/Source/JavaScriptCore/runtime/Options.h        2017-01-12 16:44:41 UTC (rev 210634)
</span><span class="lines">@@ -1,5 +1,5 @@
</span><span class="cx"> /*
</span><del>- * Copyright (C) 2011-2016 Apple Inc. All rights reserved.
</del><ins>+ * Copyright (C) 2011-2017 Apple Inc. All rights reserved.
</ins><span class="cx">  *
</span><span class="cx">  * Redistribution and use in source and binary forms, with or without
</span><span class="cx">  * modification, are permitted provided that the following conditions
</span><span class="lines">@@ -330,8 +330,6 @@
</span><span class="cx">     v(double, minHeapUtilization, 0.8, Normal, nullptr) \
</span><span class="cx">     v(double, minMarkedBlockUtilization, 0.9, Normal, nullptr) \
</span><span class="cx">     v(unsigned, slowPathAllocsBetweenGCs, 0, Normal, &quot;force a GC on every Nth slow path alloc, where N is specified by this option&quot;) \
</span><del>-    v(bool, deferGCShouldCollectWithProbability, false, Normal, &quot;If true, we perform a collection based on flipping a coin according the probability in the 'deferGCProbability' option when DeferGC is destructed.&quot;) \
-    v(double, deferGCProbability, 1.0, Normal, &quot;Should be a number between 0 and 1. 1 means DeferGC always GCs when it's destructed and GCing is safe. 0.7 means we force GC 70% the time on DeferGC destruction.&quot;) \
</del><span class="cx">     \
</span><span class="cx">     v(double, percentCPUPerMBForFullTimer, 0.0003125, Normal, nullptr) \
</span><span class="cx">     v(double, percentCPUPerMBForEdenTimer, 0.0025, Normal, nullptr) \
</span></span></pre></div>
<a id="branchessafari603branchSourceJavaScriptCoreruntimeScriptExecutablecpp"></a>
<div class="modfile"><h4>Modified: branches/safari-603-branch/Source/JavaScriptCore/runtime/ScriptExecutable.cpp (210633 => 210634)</h4>
<pre class="diff"><span>
<span class="info">--- branches/safari-603-branch/Source/JavaScriptCore/runtime/ScriptExecutable.cpp        2017-01-12 16:44:36 UTC (rev 210633)
+++ branches/safari-603-branch/Source/JavaScriptCore/runtime/ScriptExecutable.cpp        2017-01-12 16:44:41 UTC (rev 210634)
</span><span class="lines">@@ -77,8 +77,6 @@
</span><span class="cx"> 
</span><span class="cx"> void ScriptExecutable::installCode(VM&amp; vm, CodeBlock* genericCodeBlock, CodeType codeType, CodeSpecializationKind kind)
</span><span class="cx"> {
</span><del>-    ASSERT(vm.heap.isDeferred());
-    
</del><span class="cx">     if (genericCodeBlock)
</span><span class="cx">         CODEBLOCK_LOG_EVENT(genericCodeBlock, &quot;installCode&quot;, ());
</span><span class="cx">     
</span></span></pre>
</div>
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