Changeset 275648 in webkit for trunk/Source/JavaScriptCore/API/JSContext.mm

Timestamp:

Apr 7, 2021, 5:30:15 PM (4 years ago)

Author:

[email protected]

Message:

Rename and make the TerminationException a singleton.
​https://bugs.webkit.org/show_bug.cgi?id=224295

Reviewed by Keith Miller.

Source/JavaScriptCore:

We previously call it the TerminatedExecutionException, which is a mouthful but
adds no meaningful information. It's now renamed to TerminationException.

We can make it a singleton because the TerminationException is just a VM internal
mechanism for implementing the termination of the current execution stack. It
should never be exposed to user JS code, and therefore, there is no value in
making it a JS object. Making it a singleton simplifies the code.

A TerminationException is now implemented as an Exception cell which holds a
Symbol with the name "TerminationError". The TerminationException is only created
if needed e.g. if the JSC watchdog is created, or if the VM is for a Worker thread
which needs to be able to handle termination requests.

We'll also stop notifying the debugger when we throw the TerminationException.
This is because the TerminationException is not like ordinary exceptions that
should be reported to the debugger. The fact that the TerminationException uses
the exception handling mechanism is just a VM internal implementation detail.
It is not meaningful to report it to the debugger as an exception.

• API/JSContext.mm:

(-[JSContext evaluateJSScript:]):

• API/tests/ExecutionTimeLimitTest.cpp:

(testExecutionTimeLimit):

• bindings/ScriptFunctionCall.cpp:

(Deprecated::ScriptFunctionCall::call):

• heap/Heap.cpp:

(JSC::Heap::addCoreConstraints):

• inspector/InjectedScriptManager.cpp:

(Inspector::InjectedScriptManager::injectedScriptFor):

• inspector/JSGlobalObjectInspectorController.cpp:

(Inspector::JSGlobalObjectInspectorController::reportAPIException):

• interpreter/Interpreter.cpp:

(JSC::Interpreter::unwind):
(JSC::Interpreter::notifyDebuggerOfExceptionToBeThrown):

• jit/JITOperations.cpp:

(JSC::JSC_DEFINE_JIT_OPERATION):

• jsc.cpp:

(checkException):

• llint/LLIntSlowPaths.cpp:

(JSC::LLInt::LLINT_SLOW_PATH_DECL):

• runtime/ExceptionHelpers.cpp:

(JSC::TerminatedExecutionError::defaultValue): Deleted.
(JSC::createTerminatedExecutionException): Deleted.
(JSC::isTerminatedExecutionException): Deleted.
(JSC::throwTerminatedExecutionException): Deleted.

• runtime/ExceptionHelpers.h:

(): Deleted.

• runtime/JSObject.h:

(JSC::JSObject::get const):

• runtime/JSPromise.cpp:

(JSC::JSPromise::rejectWithCaughtException):

• runtime/VM.cpp:

(JSC::VM::VM):
(JSC::VM::ensureWatchdog):
(JSC::VM::ensureTerminationException):
(JSC::VM::throwTerminationException):
(JSC::VM::throwException):

• runtime/VM.h:

(JSC::VM::terminationException const):
(JSC::VM::isTerminationException const):

• runtime/VMTraps.cpp:

(JSC::VMTraps::handleTraps):

Source/WebCore:

In the WorkerOrWorkletScriptController constructor, we ensure the TerminationException
because workers need to support termination requests.

• bindings/js/JSDOMExceptionHandling.cpp:

(WebCore::reportException):

• bindings/js/JSDOMGlobalObject.cpp:

(WebCore::JSC_DEFINE_HOST_FUNCTION):
(WebCore::handleResponseOnStreamingAction):

• bindings/js/JSDOMPromise.cpp:

(WebCore::DOMPromise::whenPromiseIsSettled):

• bindings/js/JSDOMPromiseDeferred.cpp:

(WebCore::DeferredPromise::reject):

• bindings/js/JSEventListener.cpp:

(WebCore::JSEventListener::handleEvent):

• bindings/js/ReadableStream.cpp:

(WebCore::invokeReadableStreamFunction):
(WebCore::ReadableStream::lock):
(WebCore::checkReadableStream):

• bindings/js/ReadableStreamDefaultController.cpp:

(WebCore::invokeReadableStreamDefaultControllerFunction):
(WebCore::ReadableStreamDefaultController::error):
(WebCore::ReadableStreamDefaultController::enqueue):

• workers/WorkerOrWorkletScriptController.cpp:

(WebCore::WorkerOrWorkletScriptController::WorkerOrWorkletScriptController):
(WebCore::WorkerOrWorkletScriptController::evaluate):
(WebCore::WorkerOrWorkletScriptController::linkAndEvaluateModule):
(WebCore::WorkerOrWorkletScriptController::loadAndEvaluateModule):

File:

• trunk/Source/JavaScriptCore/API/JSContext.mm (modified) (2 diffs)

trunk/Source/JavaScriptCore/API/JSContext.mm

@@ -1 +1 @@
 /*
- * Copyright (C) 2013-2019 Apple Inc. All rights reserved.
+ * Copyright (C) 2013-2021 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -141 +141 @@
         JSValueRef exceptionValue = toRef(apiGlobalObject, scope.exception()->value());
         scope.clearException();
-        // FIXME: We should not clearException if it is TerminatedExecutionError.
+        // FIXME: We should not clearException if it is the TerminationException.
         // https://bugs.webkit.org/show_bug.cgi?id=220821
         return [JSValue valueWithNewPromiseRejectedWithReason:[JSValue valueWithJSValueRef:exceptionValue inContext:self] inContext:self];