Changeset 206459 in webkit for trunk/Source/JavaScriptCore/API/JSObjectRef.cpp

Timestamp:

Sep 27, 2016, 1:32:13 PM (9 years ago)

Author:

[email protected]

Message:

Add some needed CatchScopes in code that should not throw.
​https://bugs.webkit.org/show_bug.cgi?id=162584

Reviewed by Keith Miller.

Re-landing minus the jsc.cpp and ExceptionHelpers.cpp changes. I'll address
those in a subsequent patch if the need manifests again in my testing.

• API/JSObjectRef.cpp:

(JSObjectSetProperty):

• This function already handles exceptions in its own way. We're honoring this contract and catching exceptions and passing it to the handler.

• interpreter/Interpreter.cpp:

(JSC::notifyDebuggerOfUnwinding):

• The debugger should not be throwing any exceptions.

• profiler/ProfilerDatabase.cpp:

(JSC::Profiler::Database::save):

• If an exception was thrown while saving the database, there's nothing we can really do about it anyway. Just fail nicely and return false. This is in line with existing error checking code in Database::save() that returns false if it's not able to open the file to save to.

• runtime/JSModuleLoader.cpp:

(JSC::JSModuleLoader::finishCreation):

• The existing code already RELEASE_ASSERT that no exception was thrown. Hence, it's appropriate to use a CatchScope here.

• runtime/SamplingProfiler.cpp:

(JSC::SamplingProfiler::StackFrame::nameFromCallee):

• The sampling profiler is doing a VMInquiry get here. It should never throw an exception. Hence, we'll just use a CatchScope and assert accordingly.

File:

• trunk/Source/JavaScriptCore/API/JSObjectRef.cpp (modified) (2 diffs)

trunk/Source/JavaScriptCore/API/JSObjectRef.cpp

@@ -310 +310 @@
     }
     ExecState* exec = toJS(ctx);
-    JSLockHolder locker(exec);
+    VM& vm = exec->vm();
+    JSLockHolder locker(vm);
+    auto scope = DECLARE_CATCH_SCOPE(vm);
 
     JSObject* jsObject = toJS(object);
@@ -316 +318 @@
     JSValue jsValue = toJS(exec, value);
 
-    if (attributes && !jsObject->hasProperty(exec, name)) {
-        PropertyDescriptor desc(jsValue, attributes);
-        jsObject->methodTable()->defineOwnProperty(jsObject, exec, name, desc, false);
-    } else {
-        PutPropertySlot slot(jsObject);
-        jsObject->methodTable()->put(jsObject, exec, name, jsValue, slot);
-    }
-
+    bool doesNotHaveProperty = attributes && !jsObject->hasProperty(exec, name);
+    if (LIKELY(!scope.exception())) {
+        if (doesNotHaveProperty) {
+            PropertyDescriptor desc(jsValue, attributes);
+            jsObject->methodTable()->defineOwnProperty(jsObject, exec, name, desc, false);
+        } else {
+            PutPropertySlot slot(jsObject);
+            jsObject->methodTable()->put(jsObject, exec, name, jsValue, slot);
+        }
+    }
     handleExceptionIfNeeded(exec, exception);
 }