Changeset 162735 in webkit for trunk/Source/JavaScriptCore/debugger/Debugger.cpp

Timestamp:

Jan 24, 2014, 3:44:50 PM (11 years ago)

Author:

[email protected]

Message:

ASSERT(!m_markedSpace.m_currentDelayedReleaseScope) reloading page in inspector.
<​https://webkit.org/b/127582>

Reviewed by Mark Hahnenberg.

Source/JavaScriptCore:

1. We should not enter a HeapIterationScope when we iterate the CodeBlocks. Apparently, iterating the CodeBlocks does not count as heap iteration.

2. If we're detaching the debugger due to the JSGlobalObject destructing, then we don't need to clear the debugger requests in the associated CodeBlocks. The JSGlobalObject destructing would mean that those CodeBlocks would be destructing too, and it may not be safe to access them anyway at this point.

The assertion failure is because we had entered a HeapIterationScope
while the JSGlobalObject is destructing, which in turn means that GC
sweeping is in progress. It's not legal to iterate the heap while the GC
is sweeping. Once we fixed the above 2 issues, we will no longer have
the conditions that manifests this assertion failure.

• debugger/Debugger.cpp:

(JSC::Debugger::detach):
(JSC::Debugger::setSteppingMode):
(JSC::Debugger::toggleBreakpoint):
(JSC::Debugger::clearBreakpoints):
(JSC::Debugger::clearDebuggerRequests):

• debugger/Debugger.h:
• runtime/JSGlobalObject.cpp:

(JSC::JSGlobalObject::~JSGlobalObject):

Source/WebCore:

No new tests.

• bindings/js/ScriptController.cpp:

(WebCore::ScriptController::attachDebugger):

• bindings/js/WorkerScriptController.cpp:

(WebCore::WorkerScriptController::detachDebugger):

• Adding reasons for detaching a globalObject from the debugger.

File:

• trunk/Source/JavaScriptCore/debugger/Debugger.cpp (modified) (6 diffs)

trunk/Source/JavaScriptCore/debugger/Debugger.cpp

@@ -177 +177 @@
 }
 
-void Debugger::detach(JSGlobalObject* globalObject)
+void Debugger::detach(JSGlobalObject* globalObject, ReasonForDetach reason)
 {
     // If we're detaching from the currently executing global object, manually tear down our
@@ -191 +191 @@
     m_globalObjects.remove(globalObject);
 
-    clearDebuggerRequests(globalObject);
+    // If the globalObject is destructing, then its CodeBlocks will also be
+    // destructed. There is no need to do the debugger requests clean up, and
+    // it is not safe to access those CodeBlocks at this time anyway.
+    if (reason != GlobalObjectIsDestructing)
+        clearDebuggerRequests(globalObject);
+
     globalObject->setDebugger(0);
     if (!m_globalObjects.size())
@@ -229 +234 @@
     if (!m_vm)
         return;
-    HeapIterationScope iterationScope(m_vm->heap);
     SetSteppingModeFunctor functor(this, mode);
     m_vm->heap.forEachCodeBlock(functor);
@@ -314 +318 @@
     if (!m_vm)
         return;
-    HeapIterationScope iterationScope(m_vm->heap);
     ToggleBreakpointFunctor functor(this, breakpoint, enabledOrNot);
     m_vm->heap.forEachCodeBlock(functor);
@@ -494 +497 @@
     if (!m_vm)
         return;
-    HeapIterationScope iterationScope(m_vm->heap);
     ClearCodeBlockDebuggerRequestsFunctor functor(this);
     m_vm->heap.forEachCodeBlock(functor);
@@ -520 +522 @@
 {
     ASSERT(m_vm);
-    HeapIterationScope iterationScope(m_vm->heap);
     ClearDebuggerRequestsFunctor functor(globalObject);
     m_vm->heap.forEachCodeBlock(functor);