This patch merges nsAtom into nsIAtom. For the moment, both names can be used
interchangeably due to a typedef. The patch also devirtualizes nsIAtom, by
making it not inherit from nsISupports, removing NS_DECL_NSIATOM, and dropping
the use of NS_IMETHOD_. It also removes nsIAtom's IIDs.
These changes trigger knock-on changes throughout the codebase, changing the
types of lots of things as follows.
- nsCOMPtr<nsIAtom> --> RefPtr<nsIAtom>
- nsCOMArray<nsIAtom> --> nsTArray<RefPtr<nsIAtom>>
- Count() --> Length()
- ObjectAt() --> ElementAt()
- AppendObject() --> AppendElement()
- RemoveObjectAt() --> RemoveElementAt()
- ns*Hashtable<nsISupportsHashKey, ...> -->
ns*Hashtable<nsRefPtrHashKey<nsIAtom>, ...>
- nsInterfaceHashtable<T, nsIAtom> --> nsRefPtrHashtable<T, nsIAtom>
- This requires adding a Get() method to nsRefPtrHashtable that it lacks but
nsInterfaceHashtable has.
- nsCOMPtr<nsIMutableArray> --> nsTArray<RefPtr<nsIAtom>>
- nsArrayBase::Create() --> nsTArray()
- GetLength() --> Length()
- do_QueryElementAt() --> operator[]
The patch also has some changes to Rust code that manipulates nsIAtom.
MozReview-Commit-ID: DykOl8aEnUJ
This also introduces JS::GetObjectRealmOrNull, which returns an object's realm,
or null if the object is a cross-compartment wrapper. In the new order,
wrappers can't have realms, since they must be shared across all realms in a
compartment. We're introducing this new function early (even though it's
*currently* possible to assign a realm to wrappers) in order to see in
advance if the possibility of returning null will cause problems.
(It looks like it won't.)
This is a purely non-functional plumbing change. Instead of passing a
SizeOfState and an nsStyleSizes a bunch of places, we pass an nsWindowSizes,
which contains both of them.
This is a necessary precursor for the next patch.
MozReview-Commit-ID: Ek03wDM50rB
nsINode::GetSelectionRootContent() uses nsIEditor since nsContentUtils::GetHTMLEditor() returned nsIEditor. Therefore, it needed to use GetEditorRootContent() to retrieve the editor root element as nsIContent*.
Now, it can use HTMLEditor and HTMLEditor::GetRoot() returns the editor root element as nsIContent* directly. So, it should use HTMLEditor instead.
MozReview-Commit-ID: I937a5TuxVD
This patch moves measurement of ComputedValues objects from Rust to C++.
Measurement now happens (a) via DOM elements and (b) remaining elements via
the frame tree. Likewise for the style structs hanging off ComputedValues
objects.
Here is an example of the output.
> ├──27,600,448 B (26.49%) -- active/window(https://en.wikipedia.org/wiki/Barack_Obama)
> │ ├──12,772,544 B (12.26%) -- layout
> │ │ ├───4,483,744 B (04.30%) -- frames
> │ │ │ ├──1,653,552 B (01.59%) ── nsInlineFrame
> │ │ │ ├──1,415,760 B (01.36%) ── nsTextFrame
> │ │ │ ├────431,376 B (00.41%) ── nsBlockFrame
> │ │ │ ├────340,560 B (00.33%) ── nsHTMLScrollFrame
> │ │ │ ├────302,544 B (00.29%) ── nsContinuingTextFrame
> │ │ │ ├────156,408 B (00.15%) ── nsBulletFrame
> │ │ │ ├─────73,024 B (00.07%) ── nsPlaceholderFrame
> │ │ │ ├─────27,656 B (00.03%) ── sundries
> │ │ │ ├─────23,520 B (00.02%) ── nsTableCellFrame
> │ │ │ ├─────16,704 B (00.02%) ── nsImageFrame
> │ │ │ ├─────15,488 B (00.01%) ── nsTableRowFrame
> │ │ │ ├─────13,776 B (00.01%) ── nsTableColFrame
> │ │ │ └─────13,376 B (00.01%) ── nsTableFrame
> │ │ ├───3,412,192 B (03.28%) -- servo-style-structs
> │ │ │ ├──1,288,224 B (01.24%) ── Display
> │ │ │ ├────742,400 B (00.71%) ── Position
> │ │ │ ├────308,736 B (00.30%) ── Font
> │ │ │ ├────226,512 B (00.22%) ── Background
> │ │ │ ├────218,304 B (00.21%) ── TextReset
> │ │ │ ├────214,896 B (00.21%) ── Text
> │ │ │ ├────130,560 B (00.13%) ── Border
> │ │ │ ├─────81,408 B (00.08%) ── UIReset
> │ │ │ ├─────61,440 B (00.06%) ── Padding
> │ │ │ ├─────38,176 B (00.04%) ── UserInterface
> │ │ │ ├─────29,232 B (00.03%) ── Margin
> │ │ │ ├─────21,824 B (00.02%) ── sundries
> │ │ │ ├─────20,080 B (00.02%) ── Color
> │ │ │ ├─────20,080 B (00.02%) ── Column
> │ │ │ └─────10,320 B (00.01%) ── Effects
> │ │ ├───2,227,680 B (02.14%) -- computed-values
> │ │ │ ├──1,182,928 B (01.14%) ── non-dom
> │ │ │ └──1,044,752 B (01.00%) ── dom
> │ │ ├───1,500,016 B (01.44%) ── text-runs
> │ │ ├─────492,640 B (00.47%) ── line-boxes
> │ │ ├─────326,688 B (00.31%) ── frame-properties
> │ │ ├─────301,760 B (00.29%) ── pres-shell
> │ │ ├──────27,648 B (00.03%) ── pres-contexts
> │ │ └─────────176 B (00.00%) ── style-sets
The 'servo-style-structs' and 'computed-values' sub-trees are new. (Prior to
this patch, ComputedValues under DOM elements were tallied under the the
'dom/element-nodes' sub-tree, and ComputedValues not under DOM element were
ignored.) 'servo-style-structs/sundries' aggregates all the style structs that
are smaller than 8 KiB.
Other notable things done by the patch are as follows.
- It significantly changes the signatures of the methods measuring nsINode and
its subclasses, in order to handle the tallying of style structs separately
from element-nodes. Likewise for nsIFrame.
- It renames the 'layout/style-structs' sub-tree as
'layout/gecko-style-structs', to clearly distinguish it from the new
'layout/servo-style-structs' sub-tree.
- It adds some FFI functions to access various Rust-side data structures from
C++ code.
- There is a nasty hack used twice to measure Arcs, by stepping backwards from
an interior pointer to a base pointer. It works, but I want to replace it
with something better eventually. The "XXX WARNING" comments have details.
- It makes DMD print a line to the console if it sees a pointer it doesn't
recognise. This is useful for detecting when we are measuring an interior
pointer instead of a base pointer, which is bad but easy to do when Arcs are
involved.
- It removes the Rust code for measuring CVs, because it's now all done on the
C++ side.
MozReview-Commit-ID: BKebACLKtCi
All the SizeOf{In,Ex}cludingThis() functions take a MallocSizeOf function
which measures memory blocks. This patch introduces a new type, SizeOfState,
which includes a MallocSizeOf function *and* a table of already-measured
pointers, called SeenPtrs. This gives us a general mechanism to measure
graph-like data structures, by recording which nodes have already been
measured. (This approach is used in a number of existing reporters, but not in
a uniform fashion.)
The patch also converts the window memory reporting to use SizeOfState in a lot
of places, all the way through to the measurement of Elements. This is a
precursor for bug 1383977 which will measure Stylo elements, which involve
Arcs.
The patch also converts the existing mAlreadyMeasuredOrphanTrees table in the
OrphanReporter to use the new mechanism.
Unfortunately, nsGenericHTMLElement::GetAssociatedEditor() cannot use concrete classes because it may return nsIEditor which is set via nsIDocShell.editor. The editor set to nsIDocShell may be implemented by JS since nsIEditor isn't marked as builtinclass.
MozReview-Commit-ID: 6GY9LOYp4hM
In our current setup, in which links with an href attribute always match either
:link or :visited, no matter whether that attribute's value is a valid URI,
changes to the attribute always put the element into either the "match nothing"
state or the "match :link" state, via calls to Link::ResetLinkState.
The only thing FlushPendingLinkUpdates is needed for is (lazily, in case it
turns out to not be needed because the element got removed from the DOM anyway)
registering a history observer to switch the link state to :visited as needed.
This means that selector matching consumers that would never expose :visited
state to start with don't need to worry about calling FlushPendingLinkUpdates.
Internally, doRemoveChildAt does quite a bit of cleanup, and that includes some
calls to nsIDocument::GetRootElement(). Before this patch, those calls will
misleadingly return the still-present mCachedRootElement member-var. We'd
really like those invocations to find an empty cached variable, and fall back
to checking the actual updated child list.
MozReview-Commit-ID: 8hhKcWyUVYQ
I wasn't able to measure any performance improvement on talos. I
haven't tried to measure anything more specific.
However, it seems like avoiding a hashtable lookup should be worthwhile.
(At one point I thought I saw nsINode::GetProperty show up as
significant in a profile, but then I concluded I was mislead, I think
because I had focused on a very small slice of the profile and the
numbers weren't significant. I don't entirely remember since this was a
while ago.)
MozReview-Commit-ID: A9OoL9qV02D
Doing QI from nsIEditor to nsIEditorIMESupport doesn't make sense because editor should always support all methods and attributes of nsIEditorIMESupport (it does NOT mean that all nsIEditor implementation need to support IME).
This patch moves all of them to nsIEditor for avoiding redundant QIs.
MozReview-Commit-ID: DzIKuGHG4iy
