Changeset 28108 in webkit for trunk/JavaScriptCore

Timestamp:

Nov 28, 2007, 3:03:10 AM (18 years ago)

Author:

[email protected]

Message:

JavaScriptCore:

Add files missing from previous commit.

• kjs/MarkStack.h: Added.

LayoutTests:

add files missing from previous commit.

• fast/js/gc-breadth-2-expected.txt: Added.
• fast/js/gc-breadth-2.html: Added.
• fast/js/gc-breadth-expected.txt: Added.
• fast/js/gc-breadth.html: Added.
• fast/js/gc-depth-expected.txt: Added.
• fast/js/gc-depth.html: Added.
• fast/js/resources/gc-breadth-2.js: Added.
• fast/js/resources/gc-breadth.js: Added.
• fast/js/resources/gc-depth.js: Added.

Location:

trunk/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• kjs/MarkStack.h (added)

trunk/JavaScriptCore/ChangeLog

@@ +1 @@
+2007-11-28  Maciej Stachowiak  <[email protected]>
+
+        Add files missing from previous commit.
+
+        * kjs/MarkStack.h: Added.
+
+2007-11-28  Maciej Stachowiak  <[email protected]>
+
+        Not reviewed.
+
+        - Fixed "Stack overflow crash in JavaScript garbage collector mark pass"
+        http://bugs.webkit.org/show_bug.cgi?id=12216
+        
+        Implement mark stack. This version is not suitable for prime time because it makes a
+        huge allocation on every collect, and potentially makes marking of detached subtrees
+        slow. But it is a .2% - .4% speedup even without much tweaking.
+        
+        The basic approach is to replace mark() methods with
+        markChildren(MarkStack&) methods. Reachable references are pushed
+        onto a mark stack (which encapsulates ignoring already-marked
+        references). 
+        
+        Objects are no longer responsible for actually setting their own
+        mark bits, the collector does that. This means that for objects on
+        the number heap we don't have to call markChildren() at all since
+        we know there aren't any.
+        
+        The mark phase of collect pushes roots onto the mark stack
+        and drains it as often as possible.
+        
+        To make this approach viable requires a constant-size mark stack
+        and a slow fallback approach for when the stack size is exceeded,
+        plus optimizations to make the required stack small in common
+        cases. This should be doable.
+
+        * JavaScriptCore.exp: Export new symbols.
+        * JavaScriptCore.xcodeproj/project.pbxproj: Add new file.
+        * kjs/collector.cpp:
+        (KJS::Collector::heapAllocate):
+        (KJS::drainMarkStack): Helper for all of the below.
+        (KJS::Collector::markStackObjectsConservatively): Use mark stack.
+        (KJS::Collector::markCurrentThreadConservatively): ditto
+        (KJS::Collector::markOtherThreadConservatively): ditto
+        (KJS::Collector::markProtectedObjects): ditto
+        (KJS::Collector::markMainThreadOnlyObjects): ditto
+        (KJS::Collector::collect): ditto
+        * kjs/collector.h:
+        (KJS::Collector::cellMayHaveRefs): Helper for MarkStack.
+
+        * kjs/MarkStack.h: Added. The actual mark stack implementation.
+        (KJS::MarkStack::push):
+        (KJS::MarkStack::pushAtom):
+        (KJS::MarkStack::pop):
+        (KJS::MarkStack::isEmpty):
+        (KJS::MarkStack::reserveCapacity):
+
+        Changed mark() methods to markChildren() methods:
+        
+        * kjs/ExecState.cpp:
+        (KJS::ExecState::markChildren):
+        * kjs/ExecState.h:
+        * kjs/JSWrapperObject.cpp:
+        (KJS::JSWrapperObject::markChildren):
+        * kjs/JSWrapperObject.h:
+        * kjs/array_instance.cpp:
+        (KJS::ArrayInstance::markChildren):
+        * kjs/array_instance.h:
+        * kjs/bool_object.cpp:
+        (BooleanInstance::markChildren):
+        * kjs/bool_object.h:
+        * kjs/error_object.cpp:
+        * kjs/error_object.h:
+        * kjs/function.cpp:
+        (KJS::FunctionImp::markChildren):
+        (KJS::Arguments::Arguments):
+        (KJS::Arguments::markChildren):
+        (KJS::ActivationImp::markChildren):
+        * kjs/function.h:
+        * kjs/internal.cpp:
+        (KJS::GetterSetterImp::markChildren):
+        * kjs/interpreter.cpp:
+        (KJS::Interpreter::markRoots):
+        * kjs/interpreter.h:
+        * kjs/list.cpp:
+        (KJS::List::markProtectedListsSlowCase):
+        * kjs/list.h:
+        (KJS::List::markProtectedLists):
+        * kjs/object.cpp:
+        (KJS::JSObject::markChildren):
+        * kjs/object.h:
+        (KJS::ScopeChain::markChildren):
+        * kjs/property_map.cpp:
+        (KJS::PropertyMap::markChildren):
+        * kjs/property_map.h:
+        * kjs/scope_chain.h:
+        * kjs/string_object.cpp:
+        (KJS::StringInstance::markChildren):
+        * kjs/string_object.h:
+
 2007-11-28  Maciej Stachowiak  <[email protected]>