We don't want to check for exceptions after every single
line on our runtime methods. A better way to handle this
is to add the check in all methods that have direct side
effects (as e.g. writing to a property of the JS stack).
We also need to return whereever we throw an exception.
To simplify the code, ExecutionContext::throwXxx methods now
return a ReturnedValue (always undefined) for convenience.
Change-Id: Ide6c804f819c731a3f14c6c43121d08029c9fb90
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Replace all try/catch statements used when parsing
with checks for engine->hasException.
Change-Id: I4493cb600d5a3eb095c2003bb88bd031403e47c9
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Simplify the generated code. Add a special block to catch
exceptions thrown inside a catch() statement.
store the exception on the stack when entering finally and
rethrow it at the end. This ensure correct behavior for
break/continue/return statements inside finally.
Don't check for exceptions after calling push_catch_scope
and pop_scope in the JIT'ed code. This can lead to infinite
loops when throwing inside an exception handler.
Change-Id: I67e9325794e2fd25b0773b21e02fbaadb43faab0
Change-Id: Ic1ea9c0c43eec1d49177dc1ab4552a1da04e96fe
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Start the work to remove c++ exceptions from our JS
exception handling. Rather rely on engine->hasException.
Check the flag after we return from any runtime call in the
JIT.
Implement new try/catch handling code in qv4codegen and
for the JIT that doesn't rely on exceptions. As an added
bonus, we can remove the Try statement in the IR.
Change-Id: Ic95addd6ae03371c43c47e04cac26afdce23a061
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
QQmlError is public API and shouldn't expose an internal
method.
Change-Id: I7caf06af9340fefec5c96103395fe74acbf19497
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Avoid catch (...) with re-throw as it turns that this is very slow because it
throws a new exception and the unwinder starts from scratch. Instead use stack
allocated objects and cleaning destructors to restore state before continuing
with the propagation of exceptions.
Change-Id: I6d95026bcd60b58cb6258a9dae28623a46739532
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
It turns out that in QML it is not unusual that during early binding
evaluations due to the undefined order, the evaluation tries to look up
properties in objects that aren't initialized yet and thus exceptions are
thrown. Eeach thrown exception saves a stack trace, which is expensive to
generate when using the JIT, as it does full stack unwinding.
This patch implements a more light-weight approach by storing the instruction
pointer in the context before leaving JIT generated code.
Change-Id: I95e1cfd01179247dfc2c1df949828f474a23161b
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Properly protect them through Scoped values.
Change-Id: I5a0a1d5580d55ecff493419baa8959751a65f1d3
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
This makes pretty much all test cases pass with exact
garbage collection.
Change-Id: Ia874e3c17c3984afb7cfe370f9bd3ad8fe46699a
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
The code in the Exception class operates entirely on the engine's data,
so move it into ExecutionEngine instead. This eliminates the need for
a QV4::Exception class and catches and old code that tries to still do
catch (Exception &) instead of catch (...)
Change-Id: Ie608bec6af652038aca6c9423c225a4d7eb13b39
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
This patch changes the exception handling API in the engine slightly, encapsulating
any use of direct throw statements and catch blocks with concrete types. In the future
we need to be able to change the way these are implemented, in order to ensure that
the correct stack unwinding code is triggered for throw and re-throw.
This patch separates the C++ exception object thrown from the V4 exception
(that includes value, throwing context pointer) and stores the latter inside
the engine.
In order for that to compile, ExecutionEngine::StackTrace and StackFrame had to
move into the QV4 namespace directly.
In addition the syntax for catching exceptions changes from
try {
...
} catch (QV4::Exception &ex) {
ex.accept(context);
QV4::ScopedValue exceptionValue(scope, ex.value());
}
to
try {
...
} catch (...) {
QV4::ScopedValue exception(scope, context->catchException());
}
Context::catchException() checks if there's a "current" exception in the engine,
and if not assumes that we caught an unrelated exception and consequently re-throws.
partiallyUnwind() is also gone and replaced with rethrowException(), in order to
encapsulate the re-throw.
Lastly, in the future nesting try/catch blocks isn't going to be possible due to
limitations in the common C++ ABI with regards to foreign exceptions.
Change-Id: Ic81c75b057a2147e3176d8e0b4d326c14278b47d
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Fix some usages in qv4engine, and fix return types
in methods in qqmlxmlhttprequest.
Change-Id: I3d6225ca01bf7ea77fcc424914c8392bb6c3a454
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Remove Value::fromString(String *), and make
Encode safe against encoding raw Managed * pointers.
Change-Id: Ibca4668e1cbeaf85c78169d14386281659d33ef6
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
This will simplify finding the remaining direct usages of
QV4::Value that need fixing.
Change-Id: I223099727436d5748027c84c53d9dfc4028e38ed
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Don't use unprotected Values in the API anymore.
Change-Id: I8851628227fca374de24701bc8ee0908b5ae3923
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
While objects are being constructed, we don't have a reference to them
on the JS stack yet. So the constructor needs to protect itself against
being collected by putting the this object onto the JS stack.
Added an environment switch MM_EXACT_GC to test exact garbage
collection.
Change-Id: Ie37665a954de800359c272ffbebbe1488e7a8ace
Reviewed-by: Gunnar Sletta <gunnar.sletta@digia.com>
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Change-Id: I4fda83a0832760c277e629d4e658da718c0bf92b
Reviewed-by: Gunnar Sletta <gunnar.sletta@digia.com>
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
also store "toString" and "valueOf" as identifiers
in the engine and fix two places where we compared
strings the wrong way.
Change-Id: I70612221e72d43ed0e3c496e4209681bf254cded
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Added some convenience typedefs (StringRef, ObjectRef, ReturnedString,
ScopedString, ...)
Used StringRef in newBuiltinFunction() for testing.
Cleaned up the duplicated code for thrower functions.
Change-Id: I7b7676690cbe70d9eabb0a5afd0d922f0be3aefd
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Add some more convenience in the helper classes
in qscopedvalue_p.h
Make accesses to CallData safer, and change
ExecutionEngine::newObject() to return a safe
pointer.
Change-Id: I980909754ce9681cf6faa1355bab3a1e5d6dd186
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Now that we store them per QML file, they live in the type cache and
can outlive the engine. Therefore the engine needs to free to unlink
any remaining units upon destruction. This needs to be done after the
"death" of the memory manager, which is likely to sweep away any
function objects that also hold a reference to the compilation units.
Change-Id: I3968d5995289e8d2bc1e3abbb1f8be88a0ab4e03
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Add a Returned<T> that we can return instead of raw pointers
to Managed objects.
Start using the Returned<T> for a few methods.
Also clean up all our classes to use the Q_MANAGED macro instead
of manually defining their vtable.
Change-Id: I0a2962e47f3de955cd2cd8474f8f3fcc9e36d084
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
This is the correct abstraction for a builtin method.
Time to get rid of the 'old' in the name.
Change-Id: Ia386d2cc8ef0e6c269ab24da6fc8ebfac52d7f69
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Surround all calls into generated code with a
try {} catch {} statement that resets the jstack
to the correct position.
Like this we properly unwind the js stack in all cases, and
can also use stricter assertions in our ScopedCallData, etc.
classes to check that the stack is healthy.
Change-Id: I7ca03e06ea55007be683305d9c2a6898cf5fc689
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
First step towards being able to do an exact GC.
Create a stack for JS Values that is separate from the C++
stack.
Use the stack for generated methods (masm and moth).
Change-Id: I80ac0e5b5d86439dda5e9ea2b21fa0c57d8aef22
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
By setting this variable, the interpreter will always be used, even when
the JIT is available.
Change-Id: I66a439b649fd22e0d10be4f07f1e7be392b012f5
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
This speeds up the v8 regexp benchmark by a factor 2.5 :)
Change-Id: Ibd6b18ee28181aa712429cbec4598984e0c69820
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Rather use the correct internalClass directly when constructing
the objects.
Change-Id: I8e916f1ce8f83d291c08ca6332fe85b1f57b90b5
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
The prototype is actually the same for most objects. By
moving it into the internal class, we can save 8 bytes
per object, as well as allowing for some future
optimizations.
Also fix a bug in the implementation of the Error
prototype objects.
Change-Id: I4d4b641055f644a9b088f27be34bfdb0446279b7
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
This avoids one indirection when calling the methods and cleans up
the engine a bit.
Change-Id: I426f41e23f6a7262af95b9807b00920530fef642
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Choose whether we use a stack based context for a function, when
the actual closure is generated, not at call time. This speeds up
function calling for leaf functions.
Change-Id: Ibcbf3acb5610a7f59b6474e982122df03c1c5298
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>