Changeset 118269 in webkit for trunk/Source/JavaScriptCore/heap/WeakBlock.h

Timestamp:

May 23, 2012, 4:55:27 PM (13 years ago)

Author:

[email protected]

Message:

Refactored WeakBlock to use malloc, clarify behavior
​https://bugs.webkit.org/show_bug.cgi?id=87318

Reviewed by Filip Pizlo.

We want to use malloc so we can make these smaller than 4KB,
since an individual MarkedBlock will usually have fewer than
4KB worth of weak pointers.

• heap/Heap.cpp:

(JSC::Heap::markRoots): Renamed visitLiveWeakImpls to visit, since
we no longer need to distinguish from "visitDeadWeakImpls".

Renamed "visitDeadWeakImpls" to "reap" because we're not actually
doing any visiting -- we're just tagging things as dead.

• heap/WeakBlock.cpp:

(JSC::WeakBlock::create):
(JSC::WeakBlock::destroy):
(JSC::WeakBlock::WeakBlock): Malloc!

(JSC::WeakBlock::visit):
(JSC::WeakBlock::reap): Renamed as above.

• heap/WeakBlock.h:

(WeakBlock): Reduced to 3KB, as explained above.

• heap/WeakSet.cpp:

(JSC::WeakSet::visit):
(JSC::WeakSet::reap):

• heap/WeakSet.h:

(WeakSet): Updated for renames, and to match WebKit style.

File:

• trunk/Source/JavaScriptCore/heap/WeakBlock.h (modified) (6 diffs)

trunk/Source/JavaScriptCore/heap/WeakBlock.h

@@ -31 +31 @@
 #include "WeakImpl.h"
 #include <wtf/DoublyLinkedList.h>
-#include <wtf/PageAllocation.h>
 #include <wtf/StdLibExtras.h>
 
@@ -43 +42 @@
 public:
     friend class WTF::DoublyLinkedListNode<WeakBlock>;
-    static const size_t blockSize = 4 * KB;
+    static const size_t blockSize = 3 * KB; // 5% of MarkedBlock size
 
     struct FreeCell {
@@ -65 +64 @@
 
     void sweep();
-    const SweepResult& sweepResult();
     SweepResult takeSweepResult();
 
-    void visitLiveWeakImpls(HeapRootVisitor&);
-    void visitDeadWeakImpls(HeapRootVisitor&);
+    void visit(HeapRootVisitor&);
+    void reap();
 
     void lastChanceToFinalize();
@@ -76 +74 @@
     static FreeCell* asFreeCell(WeakImpl*);
 
-    WeakBlock(PageAllocation&);
+    WeakBlock();
     WeakImpl* firstWeakImpl();
     void finalize(WeakImpl*);
@@ -83 +81 @@
     void addToFreeList(FreeCell**, WeakImpl*);
 
-    PageAllocation m_allocation;
     WeakBlock* m_prev;
     WeakBlock* m_next;
@@ -112 +109 @@
     ASSERT(m_sweepResult.isNull());
     return tmp;
-}
-
-inline const WeakBlock::SweepResult& WeakBlock::sweepResult()
-{
-    return m_sweepResult;
 }