Changeset 112624 in webkit for trunk/Source/JavaScriptCore/runtime/JSGlobalData.cpp

Timestamp:

Mar 29, 2012, 5:36:37 PM (13 years ago)

Author:

[email protected]

Message:

Refactor recompileAllJSFunctions() to be less expensive
​https://bugs.webkit.org/show_bug.cgi?id=80330

Reviewed by Filip Pizlo.

This change is performance neutral on the JS benchmarks we track. It's mostly to improve page
load performance, which currently does at least a couple full GCs per navigation.

• heap/Heap.cpp:

(JSC::Heap::discardAllCompiledCode): Rename recompileAllJSFunctions to discardAllCompiledCode
because the function doesn't actually recompile anything (and never did); it simply throws code
away for it to be recompiled later if we determine we should do so.
(JSC):
(JSC::Heap::collectAllGarbage):
(JSC::Heap::addFunctionExecutable): Adds a newly created FunctionExecutable to the Heap's list.
(JSC::Heap::removeFunctionExecutable): Removes the specified FunctionExecutable from the Heap's list.

• heap/Heap.h:

(JSC):
(Heap):

• runtime/Executable.cpp: Added next and prev fields to FunctionExecutables so that they can

be used in DoublyLinkedLists.
(JSC::FunctionExecutable::FunctionExecutable):
(JSC::FunctionExecutable::finalize): Removes the FunctionExecutable from the Heap's list.

• runtime/Executable.h:

(FunctionExecutable):
(JSC::FunctionExecutable::create): Adds the FunctionExecutable to the Heap's list.

• runtime/JSGlobalData.cpp: Remove recompileAllJSFunctions, as it's the Heap's job to own and manage

the list of FunctionExecutables.

• runtime/JSGlobalData.h:

(JSGlobalData):

• runtime/JSGlobalObject.cpp:

(JSC::DynamicGlobalObjectScope::DynamicGlobalObjectScope): Use the new discardAllCompiledCode.

File:

• trunk/Source/JavaScriptCore/runtime/JSGlobalData.cpp (modified) (2 diffs)

trunk/Source/JavaScriptCore/runtime/JSGlobalData.cpp

@@ -69 +69 @@
 using namespace WTF;
 
-namespace {
-
-using namespace JSC;
-
-class Recompiler : public MarkedBlock::VoidFunctor {
-public:
-    void operator()(JSCell*);
-};
-
-inline void Recompiler::operator()(JSCell* cell)
-{
-    if (!cell->inherits(&JSFunction::s_info))
-        return;
-    JSFunction* function = jsCast<JSFunction*>(cell);
-    if (!function->executable() || function->executable()->isHostFunction())
-        return;
-    function->jsExecutable()->discardCode();
-}
-
-} // namespace
-
 namespace JSC {
 
@@ -444 +423 @@
 }
 
-void JSGlobalData::recompileAllJSFunctions()
-{
-    // If JavaScript is running, it's not safe to recompile, since we'll end
-    // up throwing away code that is live on the stack.
-    ASSERT(!dynamicGlobalObject);
-    
-    heap.objectSpace().forEachCell<Recompiler>();
-}
-
 struct StackPreservingRecompiler : public MarkedBlock::VoidFunctor {
     HashSet<FunctionExecutable*> currentlyExecutingFunctions;