855145 - DeMACROize (some of) the JS tracing interface

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Terrence Cole [:terrence]]

Attachment: v0: js half

This demacroizes all of the CALL_TRACER routines. It also uses the statically known type of the traced thing to call the right function immediately, rather than casting it away, looking it up in the arena, then switching to get the right function.

One noticeable exception is that ccParticipant marking still requires a generic void* for tracing. I'm not sure if it will be necessary (or possible) to fix this for GGC yet; I will look into it more later.

Comment 1

[Terrence Cole [:terrence]]

Attachment: v0: browser half

And this is the browser half. It is almost completely mechanical.

Comment 2

[Andrew McCreight [:mccr8]]

Comment on attachment 729904 [details] [diff] [review]
v0: browser half

Review of attachment 729904 [details] [diff] [review]:
-----------------------------------------------------------------

Please make sure you can do a cycle collector dump at least once without crashing with this patch in place.

https://wiki.mozilla.org/Performance:Leak_Tools#Cycle_collector_heap_dump

Comment 3

[Bill McCloskey [inactive unless it's an emergency] (:billm)]

Comment on attachment 729903 [details] [diff] [review]
v0: js half

Review of attachment 729903 [details] [diff] [review]:
-----------------------------------------------------------------

::: js/src/jsapi.cpp
@@ +2441,5 @@
>  JS_PUBLIC_API(void)
> +JS_CallValueTracer(JSTracer *trc, Value valueArg, const char *name)
> +{
> +    Value value = valueArg;
> +    MarkValueUnbarriered(trc, &value, name);

Can you add assertions in each one of these that the thing hasn't moved?

@@ +2479,5 @@
> +    void *gcthing = gcthingArg;
> +    Cell *cell = static_cast<gc::Cell *>(gcthing);
> +    JSGCTraceKind kind = gc::IsInsideNursery(cell->runtime(), gcthing)
> +                         ? JSTRACE_OBJECT
> +                         : gc::MapAllocToTraceKind(cell->tenuredGetAllocKind());

Just use GetGCThingTraceKind here.

Comment 4

[Terrence Cole [:terrence]]

Try run at:
https://tbpl.mozilla.org/?tree=Try&rev=844973a2cdd4
Pushed at:
https://hg.mozilla.org/integration/mozilla-inbound/rev/2cb5ad80203e

Comment 5

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/2cb5ad80203e