void
ObjectGroupCycleCollectorTracer::onChild(const JS::GCCellPtr& thing)
{
if (thing.is<JSObject>() || thing.is<JSScript>()) {
// Invoke the inner cycle collector callback on this child. It will not
// recurse back into TraceChildren.
innerTracer->onChild(thing);
return;
}
if (thing.is<ObjectGroup>()) {
// If this group is required to be in an ObjectGroup chain, trace it
// via the provided worklist rather than continuing to recurse.
ObjectGroup& group = thing.as<ObjectGroup>();
if (group.maybeUnboxedLayout()) {
for (size_t i = 0; i < seen.length(); i++) {
if (seen[i] == &group)
return;
}
if (seen.append(&group) && worklist.append(&group)) {
return;
} else {
// If append fails, keep tracing normally. The worst that will
// happen is we end up overrecursing.
}
}
}
TraceChildren(this, thing.asCell(), thing.kind());
}
/*
* This function is called by EndVerifyBarriers for every heap edge. If the edge
* already existed in the original snapshot, we "cancel it out" by overwriting
* it with nullptr. EndVerifyBarriers later asserts that the remaining
* non-nullptr edges (i.e., the ones from the original snapshot that must have
* been modified) must point to marked objects.
*/
void
CheckEdgeTracer::onChild(const JS::GCCellPtr& thing)
{
/* Avoid n^2 behavior. */
if (node->count > MAX_VERIFIER_EDGES)
return;
for (uint32_t i = 0; i < node->count; i++) {
if (node->edges[i].thing == thing.asCell()) {
MOZ_ASSERT(node->edges[i].kind == thing.kind());
node->edges[i].thing = nullptr;
return;
}
}
}
void
nsScriptObjectTracer::NoteJSChild(JS::GCCellPtr aGCThing, const char* aName,
void* aClosure)
{
nsCycleCollectionTraversalCallback* cb =
static_cast<nsCycleCollectionTraversalCallback*>(aClosure);
NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(*cb, aName);
if (aGCThing.is<JSObject>()) {
cb->NoteJSObject(&aGCThing.as<JSObject>());
} else if (aGCThing.is<JSScript>()) {
cb->NoteJSScript(&aGCThing.as<JSScript>());
} else {
MOZ_ASSERT(!mozilla::AddToCCKind(aGCThing.kind()));
}
}
/*
* This function builds up the heap snapshot by adding edges to the current
* node.
*/
void
VerifyPreTracer::onChild(const JS::GCCellPtr& thing)
{
MOZ_ASSERT(!IsInsideNursery(thing.asCell()));
edgeptr += sizeof(EdgeValue);
if (edgeptr >= term) {
edgeptr = term;
return;
}
VerifyNode* node = curnode;
uint32_t i = node->count;
node->edges[i].thing = thing.asCell();
node->edges[i].kind = thing.kind();
node->edges[i].label = contextName();
node->count++;
}
Node::Node(const JS::GCCellPtr &thing)
{
DispatchTraceKindTyped(ConstructFunctor(), thing.asCell(), thing.kind(), this);
}
Node::Node(const JS::GCCellPtr &thing)
{
js::gc::CallTyped(ConstructFunctor(), thing.asCell(), thing.kind(), this);
}