Import WebIDL/Function.idl where TimerHandler uses Function, and let the
bindings generator handle it through the normal callback-function path.
This removes the special C++ mapping for Function and makes TimerHandler
use GC::Root<CallbackType>, matching the generated binding type when IDL
files are parsed together.
Previously, the LibWeb bindings generator would output multiple per
interface files like Prototype/Constructor/Namespace/GlobalMixin
depending on the contents of that IDL file.
This complicates the build system as it means that it does not know
what files will be generated without knowledge of the contents of that
IDL file.
Instead, for each IDL file only generate a single Bindings/<IDLFile>.h
and Bindings/<IDLFile>.cpp.
Split JS::ErrorData out of JS::Error so that it can be used both
by JS::Error and WebIDL::DOMException. This adds support for
Error.isError to DOMException, also letting us report DOMException
stack information to the console.
Use dedicated Packed branches in GetByValue and PutByValue so
in-bounds indexed accesses can skip hole checks and slot
reloads.
Keep Holey writes on the guarded arm, and keep append writes on
the C++ slow path so PutByValue still respects non-extensible
indexed objects and arrays with a non-writable length.
Add a bytecode regression that exercises both append failure
cases through the real js binary path.
Replace the OwnPtr<IndexedPropertyStorage> indirection with inline
indexed element storage directly on Object. This eliminates virtual
dispatch and reduces indirection for indexed property access.
The new system uses three storage kinds tracked by IndexedStorageKind:
- Packed: Dense array, no holes. Elements stored in a malloced Value*
array with capacity header (same layout as named properties).
- Holey: Dense array with possible holes marked by empty sentinel.
Same physical layout as Packed.
- Dictionary: Sparse storage using GenericIndexedPropertyStorage,
type-punned into the m_indexed_elements pointer.
Transitions: None->Packed->Holey->Dictionary (mostly monotonic).
Dictionary mode triggers on non-default attributes or sparse arrays.
Object keeps the same 48-byte size since m_indexed_elements (8 bytes)
replaces IndexedProperties (8 bytes), and the storage kind + array
size fit in existing padding alongside m_flags.
The asm interpreter benefits from one fewer indirection: it now reads
the element pointer and array size directly from Object fields instead
of chasing through OwnPtr -> IndexedPropertyStorage -> Vector.
Removes: IndexedProperties, SimpleIndexedPropertyStorage,
IndexedPropertyStorage, IndexedPropertyIterator.
Keeps: GenericIndexedPropertyStorage (for Dictionary mode).
By making use of the WEB_PLATFORM_OBJECT macro we can remove
the boilerplate of needing to add this override for every
serializable platform object so that we can check whether they
are exposed or not.
While this does cost us an extra byte to serialize as it
contains _all_ interface names instead of the set of serializable
types, doing this will allow us to remove to use the same
enum for checking whether that interface is exposed in a future
commit.
Remove 11 heavy includes from Document.h that were only needed for
pointer/reference types (already forward-declared in Forward.h), and
extract the nested ViewportClient interface to a standalone header.
This reduces Document.h's recompilation cascade from ~1228 files to
~717 files (42% reduction). Headers like BrowsingContext.h that were
previously transitively included see even larger improvements (from
~1228 down to ~73 dependents).
The C round differs from the web standard if the value lies exactly at
the middle point. C rounds away from 0 while the web moves to the even
value of the 2 extremes.
This fixes at least 5 tests :)
We already had IC support in PutById for the following cases:
- Changing an existing own property
- Calling a setter located in the prototype chain
This was enough to speed up code where structurally identical objects
(same shape) are processed in a loop:
```js
const arr = [{ a: 1 }, { a: 2 }, { a: 3 }];
for (let obj of arr) {
obj.a += 1;
}
```
However, creating structurally identical objects in a loop was still
slow:
```js
for (let i = 0; i < 10_000_000; i++) {
const o = {};
o.a = 1;
o.b = 2;
o.c = 3;
}
```
This change addresses that by adding a new IC type that caches both the
source and target shapes, allowing property additions to be fast-pathed
by directly jumping to the shape that already includes the new property.
Adds inline implementation for the most common case when `Value` is
already an object.
1.47x improvement on the following benchmark:
```js
const o = {};
for (let i = 0; i < 10_000_000; i++) {
o.a = 1;
o.b = 2;
o.c = 3;
}
```
This has quite a lot of fall out. But the majority of it is just type or
UDL substitution, where the changes just fall through to other function
calls.
By changing property key storage to UTF-16, the main affected areas are:
* NativeFunction names must now be UTF-16
* Bytecode identifiers must now be UTF-16
* Module/binding names must now be UTF-16
Our structured serialization implementation had its own bespoke encoder
and decoder to serialize JS values. It also used a u32 buffer under the
hood, which made using its structures a bit awkward. We had previously
worked around its data structures in transferable streams, which nested
transfers of MessagePort instances. We basically had to add hooks into
the MessagePort to route to the correct transfer receiving steps, and
we could not invoke the correct AOs directly as the spec dictates.
We now use IPC mechanics to encode and decode data. This works because,
although we are encoding JS values, we are only ultimately encoding
primitive and basic AK types. The resulting data structures actually
enforce that we implement transferable streams exactly as the spec is
worded (I had planned to do that in a separate commit, but the fallout
of this patch actually required that change).
Our currently implementation of structured serialization has a design
flaw, where if the serialized/transferred type was not used in the
destination realm, it would not be seen as exposed and thus we would
not re-create the type on the other side.
This is very common, for example, transferring a MessagePort to a just
inserted iframe, or the just inserted iframe transferring a MessagePort
to it's parent. This is what Google reCAPTCHA does.
This flaw occurred due to relying on lazily populated HashMaps of
constructors, namespaces and interfaces. This commit changes it so that
per-type "is exposed" implementations are generated.
Since it no longer relies on interface name strings, this commit
changes serializable types to indicate their type with an enum,
in line with how transferrable types indicate their type.
This makes Google reCAPTCHA work on https://www.google.com/recaptcha/api2/demo
It currently doesn't work on non-Google origins due to a separate
same-origin policy bug.
...when Array.prototype and Object.prototype are intact.
If `internal_set()` is called on an array exotic object with a numeric
PropertyKey, and:
- the prototype chain has not been modified (i.e., there are no getters
or setters for indexed properties), and
- the array is not the target of a Proxy object,
then we can directly store the value in the receiver's indexed
properties, without checking whether it already exists somewhere in the
prototype chain.
1.7x improvement on the following program:
```js
function f() {
let a = [];
let i = 0;
while (i < 10_000_000) {
a.push(i);
i++;
}
}
f();
```
This is *extremely* common on the web, but barely shows up at all in
JavaScript benchmarks.
A typical example is setting Element.innerHTML on a HTMLDivElement.
HTMLDivElement doesn't have innerHTML, so it has to travel up the
prototype chain until it finds it.
Before this change, we didn't cache this at all, so we had to travel
the prototype chain every time a setter like this was used.
We now use the same mechanism we already had for GetBydId and cache
PutById setter accesses in the prototype chain as well.
1.74x speedup on MicroBench/setter-in-prototype-chain.js
For attributes like Element.ariaControlsElements, which are a reflection
of FrozenArray<Element>, we must return the same JS::Array object every
time the attribute is invoked - until its contents have changed. This
patch implements caching of the reflected array in accordance with the
spec.
Before this change, we were going through the chain of base classes for
each IDL interface object and having them set the prototype to their
prototype.
Instead of doing that, reorder things so that we set the right prototype
immediately in Foo::initialize(), and then don't bother in all the base
class overrides.
This knocks off a ~1% profile item on Speedometer 3.
These callbacks are evaluated synchronously via JS::Call. We do not need
to construct an expensive RootVector container just to immediately
invoke the callbacks.
Stylistically, this also helps indicate where the actual arguments start
at the call sites, by wrapping the arguments in braces.
When we need the callback to return a promise, we can use this alternate
invoker to construct the WebIDL::Promise for us. Currently, the Streams
API will use WebIDL::invoke_callback to create a JS::Promise, and then
wrap that result in a resolved WebIDL::Promise. This results in rejected
JS::Promise instances not being propagated.
This adds support for async iterators of the form:
async iterable<value_type>;
async iterable<value_type>(/* arguments... */);
It does not yet support the value pairs of the form:
async iterable<key_type, value_type>;
async iterable<key_type, value_type>(/* arguments... */);
Async iterators have an optional `return` data property. There's not a
particularly good way to know what interfaces implement this property.
So this adds a new extended attribute, DefinesAsyncIteratorReturn, which
interfaces can use to declare their support.
Our existing implementation of stream piping was extremely ad-hoc. It
did nothing to handle closed/errored streams, and did not read from or
write to streams in a way required by the spec.
This new implementation uses a custom JS::Cell to drive the read/write
loop.