Bug 1164042 - Log weak map entries in DumpHeapComplete. r=terrence

js/src/jsfriendapi.cpp

@@ -886,14 +886,31 @@ JS::FormatStackDump(JSContext* cx, char* buf, bool showArgs, bool showLocals, bo
     return buf;
 }
 
-struct DumpHeapTracer : public JS::CallbackTracer
+struct DumpHeapTracer : public JS::CallbackTracer, public WeakMapTracer
 {
     FILE*  output;
 
-    DumpHeapTracer(FILE* fp, JSRuntime* rt, JSTraceCallback callback,
-                   WeakMapTraceKind weakTraceKind)
-      : JS::CallbackTracer(rt, callback, weakTraceKind), output(fp)
+    DumpHeapTracer(FILE* fp, JSRuntime* rt, JSTraceCallback callback)
+      : JS::CallbackTracer(rt, callback, DoNotTraceWeakMaps),
+        js::WeakMapTracer(rt, DumpWeakMap), output(fp)
     {}
+
+private:
+    static void
+    DumpWeakMap(js::WeakMapTracer* trc, JSObject* map,
+                JS::GCCellPtr key, JS::GCCellPtr value)
+    {
+        DumpHeapTracer* tracer =
+            static_cast<DumpHeapTracer*>(trc);
+
+        JSObject* kdelegate = nullptr;
+        if (key.isObject()) {
+            kdelegate = js::GetWeakmapKeyDelegate(key.toObject());
+        }
+
+        fprintf(tracer->output, "WeakMapEntry map=%p key=%p keyDelegate=%p value=%p\n",
+                map, key.asCell(), kdelegate, value.asCell());
+    }
 };
 
 static char
@@ -976,9 +993,13 @@ js::DumpHeapComplete(JSRuntime* rt, FILE* fp, js::DumpHeapNurseryBehaviour nurse
     if (nurseryBehaviour == js::CollectNurseryBeforeDump)
         rt->gc.evictNursery(JS::gcreason::API);
 
-    DumpHeapTracer dtrc(fp, rt, DumpHeapVisitRoot, TraceWeakMapKeysValues);
+    DumpHeapTracer dtrc(fp, rt, DumpHeapVisitRoot);
+    fprintf(dtrc.output, "# Roots.\n");
     TraceRuntime(&dtrc);
 
+    fprintf(dtrc.output, "# Weak maps.\n");
+    WeakMapBase::traceAllMappings(&dtrc);
+
     fprintf(dtrc.output, "==========\n");
 
     dtrc.setTraceCallback(DumpHeapVisitChild);

js/src/jsweakmap.cpp

@@ -48,9 +48,9 @@ WeakMapBase::trace(JSTracer* tracer)
     MOZ_ASSERT(isInList());
     if (tracer->isMarkingTracer()) {
         // We don't trace any of the WeakMap entries at this time, just record
-        // record the fact that the WeakMap has been marked. Enties are marked
+        // record the fact that the WeakMap has been marked. Entries are marked
         // in the iterative marking phase by markAllIteratively(), which happens
-        // when many keys as possible have been marked already.
+        // when as many keys as possible have been marked already.
         MOZ_ASSERT(tracer->eagerlyTraceWeakMaps() == DoNotTraceWeakMaps);
         marked = true;
     } else {