420514 - add knowledge of edge names to cycle collector, ifdef DEBUG_CC

Status: RESOLVED FIXED

(Core :: XPCOM, defect)

Description

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Attachment: patch

For a bunch of cycle collector debugging stuff I've wanted names for the edges.  This adds them in a way that makes providing an edge name optional, makes it so that all the traversal macros provide edge names (which means two of them need to require edge names as a parameter, but that hits a total of four (?) callers outside of nsCycleCollectionParticipant.h), reports the edge names in some of the DEBUG_CC code, and adds edge name information to a few of the callers that I happened to care about today.

Comment 1

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Attachment: patch

Oops, that introduced an nsCStringArray leak (not memory, but ctor/dtor matching) since we constructed the PtrInfo twice.  This makes it so we allocate NodePool::Block with NS_Alloc/NS_Free instead of new/delete so we don't do that.

Comment 2

[Peter Van der Beken [:peterv]]

Comment on attachment 306814 [details] [diff] [review]
patch

>diff --git a/xpcom/glue/nsCycleCollectionParticipant.h b/xpcom/glue/nsCycleCollectionParticipant.h
>--- a/xpcom/glue/nsCycleCollectionParticipant.h
>+++ b/xpcom/glue/nsCycleCollectionParticipant.h

>-#define NS_IMPL_CYCLE_COLLECTION_TRAVERSE_NSTARRAY(_array, _element_class)     \
>+#define NS_IMPL_CYCLE_COLLECTION_TRAVERSE_NSTARRAY(_array, _element_class, _name) \

Maybe rewrap this.

Comment 3

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Comment on attachment 306814 [details] [diff] [review]
patch

This is mostly DEBUG_CC only, and helps quite a bit when debugging leaks, but it does add a bunch of calls to macros (that are empty when DEBUG_CC is not defined) to non-DEBUG_CC code, so I should probably request approval for it.

Comment 4

[Damon Sicore (:damons)]

Comment on attachment 306814 [details] [diff] [review]
patch

a1.9+=damons

Comment 5

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Checked in to trunk.

We can certainly add names for more edges in later patches, but I'll mark this bug fixed at this point.