Bug 1132706 - Lazify hashing for insertions into the NewObjectCache; r=jonco

--HG--
extra : rebase_source : 9435fdbada6cc43d6e59cddef93d17572f423cba

js/src/jsarray.cpp

@@ -3329,6 +3329,14 @@ EnsureNewArrayElements(ExclusiveContext *cx, ArrayObject *obj, uint32_t length)
     return true;
 }
 
+static bool
+NewArrayIsCachable(ExclusiveContext *cxArg, NewObjectKind newKind)
+{
+    return cxArg->isJSContext() &&
+           newKind == GenericObject &&
+           !cxArg->asJSContext()->compartment()->hasObjectMetadataCallback();
+}
+
 template <uint32_t maxLength>
 static MOZ_ALWAYS_INLINE ArrayObject *
 NewArray(ExclusiveContext *cxArg, uint32_t length,
@@ -3338,15 +3346,13 @@ NewArray(ExclusiveContext *cxArg, uint32_t length,
     MOZ_ASSERT(CanBeFinalizedInBackground(allocKind, &ArrayObject::class_));
     allocKind = GetBackgroundAllocKind(allocKind);
 
-    NewObjectCache::EntryIndex entry = -1;
-    uint64_t gcNumber = 0;
-    if (JSContext *cx = cxArg->maybeJSContext()) {
+    bool isCachable = NewArrayIsCachable(cxArg, newKind);
+    if (isCachable) {
+        JSContext *cx = cxArg->asJSContext();
         JSRuntime *rt = cx->runtime();
         NewObjectCache &cache = rt->newObjectCache;
-        if (newKind == GenericObject &&
-            !cx->compartment()->hasObjectMetadataCallback() &&
-            cache.lookupGlobal(&ArrayObject::class_, cx->global(), allocKind, &entry))
-        {
+        NewObjectCache::EntryIndex entry = -1;
+        if (cache.lookupGlobal(&ArrayObject::class_, cx->global(), allocKind, &entry)) {
             gc::InitialHeap heap = GetInitialHeap(newKind, &ArrayObject::class_);
             JSObject *obj = cache.newObjectFromHit(cx, entry, heap);
             if (obj) {
@@ -3361,8 +3367,6 @@ NewArray(ExclusiveContext *cxArg, uint32_t length,
                 }
                 return arr;
             }
-        } else {
-            gcNumber = rt->gc.gcNumber();
         }
     }
 
@@ -3405,11 +3409,11 @@ NewArray(ExclusiveContext *cxArg, uint32_t length,
     if (newKind == SingletonObject && !JSObject::setSingleton(cxArg, arr))
         return nullptr;
 
-    if (entry != -1 &&
-        cxArg->asJSContext()->runtime()->gc.gcNumber() == gcNumber)
-    {
-        cxArg->asJSContext()->runtime()->newObjectCache.fillGlobal(entry, &ArrayObject::class_,
-                                                                   cxArg->global(), allocKind, arr);
+    if (isCachable) {
+        NewObjectCache &cache = cxArg->asJSContext()->runtime()->newObjectCache;
+        NewObjectCache::EntryIndex entry = -1;
+        cache.lookupGlobal(&ArrayObject::class_, cxArg->global(), allocKind, &entry);
+        cache.fillGlobal(entry, &ArrayObject::class_, cxArg->global(), allocKind, arr);
     }
 
     if (maxLength > 0 && !EnsureNewArrayElements(cxArg, arr, std::min(maxLength, length)))

js/src/jsobj.cpp

@@ -1218,6 +1218,20 @@ NewObjectCache::fillProto(EntryIndex entry, const Class *clasp, js::TaggedProto
     return fill(entry, clasp, proto.raw(), kind, obj);
 }
 
+static bool
+NewObjectWithTaggedProtoIsCachable(ExclusiveContext *cxArg, Handle<TaggedProto> proto,
+                                   NewObjectKind newKind, const Class *clasp,
+                                   HandleObject parentArg)
+{
+    return cxArg->isJSContext() &&
+           proto.isObject() &&
+           newKind == GenericObject &&
+           clasp->isNative() &&
+           !cxArg->asJSContext()->compartment()->hasObjectMetadataCallback() &&
+           (!parentArg || parentArg == proto.toObject()->getParent()) &&
+           !proto.toObject()->is<GlobalObject>();
+}
+
 JSObject *
 js::NewObjectWithGivenTaggedProto(ExclusiveContext *cxArg, const Class *clasp,
                                   Handle<TaggedProto> proto, HandleObject parentArg,
@@ -1226,25 +1240,16 @@ js::NewObjectWithGivenTaggedProto(ExclusiveContext *cxArg, const Class *clasp,
     if (CanBeFinalizedInBackground(allocKind, clasp))
         allocKind = GetBackgroundAllocKind(allocKind);
 
-    NewObjectCache::EntryIndex entry = -1;
-    uint64_t gcNumber = 0;
-    if (JSContext *cx = cxArg->maybeJSContext()) {
+    bool isCachable = NewObjectWithTaggedProtoIsCachable(cxArg, proto, newKind, clasp, parentArg);
+    if (isCachable) {
+        JSContext *cx = cxArg->asJSContext();
         JSRuntime *rt = cx->runtime();
         NewObjectCache &cache = rt->newObjectCache;
-        if (proto.isObject() &&
-            newKind == GenericObject &&
-            clasp->isNative() &&
-            !cx->compartment()->hasObjectMetadataCallback() &&
-            (!parentArg || parentArg == proto.toObject()->getParent()) &&
-            !proto.toObject()->is<GlobalObject>())
-        {
-            if (cache.lookupProto(clasp, proto.toObject(), allocKind, &entry)) {
-                JSObject *obj = cache.newObjectFromHit(cx, entry, GetInitialHeap(newKind, clasp));
-                if (obj)
-                    return obj;
-            } else {
-                gcNumber = rt->gc.gcNumber();
-            }
+        NewObjectCache::EntryIndex entry = -1;
+        if (cache.lookupProto(clasp, proto.toObject(), allocKind, &entry)) {
+            JSObject *obj = cache.newObjectFromHit(cx, entry, GetInitialHeap(newKind, clasp));
+            if (obj)
+                return obj;
         }
     }
 
@@ -1264,12 +1269,11 @@ js::NewObjectWithGivenTaggedProto(ExclusiveContext *cxArg, const Class *clasp,
     if (!obj)
         return nullptr;
 
-    if (entry != -1 && !obj->as<NativeObject>().hasDynamicSlots() &&
-        cxArg->asJSContext()->runtime()->gc.gcNumber() == gcNumber)
-    {
-        cxArg->asJSContext()->runtime()->newObjectCache.fillProto(entry, clasp,
-                                                                  proto, allocKind,
-                                                                  &obj->as<NativeObject>());
+    if (isCachable && !obj->as<NativeObject>().hasDynamicSlots()) {
+        NewObjectCache &cache = cxArg->asJSContext()->runtime()->newObjectCache;
+        NewObjectCache::EntryIndex entry = -1;
+        cache.lookupProto(clasp, proto.toObject(), allocKind, &entry);
+        cache.fillProto(entry, clasp, proto, allocKind, &obj->as<NativeObject>());
     }
 
     return obj;
@@ -1369,6 +1373,17 @@ FindProto(ExclusiveContext *cx, const js::Class *clasp, MutableHandleObject prot
     return true;
 }
 
+static bool
+NewObjectWithClassProtoIsCachable(ExclusiveContext *cxArg, HandleObject parent,
+                                  JSProtoKey protoKey, NewObjectKind newKind, const Class *clasp)
+{
+    return cxArg->isJSContext() &&
+           parent->is<GlobalObject>() &&
+           protoKey != JSProto_Null &&
+           newKind == GenericObject &&
+           clasp->isNative() &&
+           !cxArg->asJSContext()->compartment()->hasObjectMetadataCallback();
+}
 
 JSObject *
 js::NewObjectWithClassProtoCommon(ExclusiveContext *cxArg, const Class *clasp,
@@ -1396,24 +1411,16 @@ js::NewObjectWithClassProtoCommon(ExclusiveContext *cxArg, const Class *clasp,
      */
     JSProtoKey protoKey = ClassProtoKeyOrAnonymousOrNull(clasp);
 
-    NewObjectCache::EntryIndex entry = -1;
-    uint64_t gcNumber = 0;
-    if (JSContext *cx = cxArg->maybeJSContext()) {
+    bool isCachable = NewObjectWithClassProtoIsCachable(cxArg, parent, protoKey, newKind, clasp);
+    if (isCachable) {
+        JSContext *cx = cxArg->asJSContext();
         JSRuntime *rt = cx->runtime();
         NewObjectCache &cache = rt->newObjectCache;
-        if (parent->is<GlobalObject>() &&
-            protoKey != JSProto_Null &&
-            newKind == GenericObject &&
-            clasp->isNative() &&
-            !cx->compartment()->hasObjectMetadataCallback())
-        {
-            if (cache.lookupGlobal(clasp, &parent->as<GlobalObject>(), allocKind, &entry)) {
-                JSObject *obj = cache.newObjectFromHit(cx, entry, GetInitialHeap(newKind, clasp));
-                if (obj)
-                    return obj;
-            } else {
-                gcNumber = rt->gc.gcNumber();
-            }
+        NewObjectCache::EntryIndex entry = -1;
+        if (cache.lookupGlobal(clasp, &parent->as<GlobalObject>(), allocKind, &entry)) {
+            JSObject *obj = cache.newObjectFromHit(cx, entry, GetInitialHeap(newKind, clasp));
+            if (obj)
+                return obj;
         }
     }
 
@@ -1430,17 +1437,29 @@ js::NewObjectWithClassProtoCommon(ExclusiveContext *cxArg, const Class *clasp,
     if (!obj)
         return nullptr;
 
-    if (entry != -1 && !obj->as<NativeObject>().hasDynamicSlots() &&
-        cxArg->asJSContext()->runtime()->gc.gcNumber() == gcNumber)
-    {
-        cxArg->asJSContext()->runtime()->newObjectCache.fillGlobal(entry, clasp,
-                                                                   &parent->as<GlobalObject>(),
-                                                                   allocKind, &obj->as<NativeObject>());
+    if (isCachable && !obj->as<NativeObject>().hasDynamicSlots()) {
+        NewObjectCache &cache = cxArg->asJSContext()->runtime()->newObjectCache;
+        NewObjectCache::EntryIndex entry = -1;
+        cache.lookupGlobal(clasp, &parent->as<GlobalObject>(), allocKind, &entry);
+        cache.fillGlobal(entry, clasp, &parent->as<GlobalObject>(), allocKind,
+                         &obj->as<NativeObject>());
     }
 
     return obj;
 }
 
+static bool
+NewObjectWithGroupIsCachable(JSContext *cx, HandleObjectGroup group, HandleObject parent,
+                             NewObjectKind newKind)
+{
+    return group->proto().isObject() &&
+           parent == group->proto().toObject()->getParent() &&
+           newKind == GenericObject &&
+           group->clasp()->isNative() &&
+           (!group->newScript() || group->newScript()->analyzed()) &&
+           !cx->compartment()->hasObjectMetadataCallback();
+}
+
 /*
  * Create a plain object with the specified group. This bypasses getNewGroup to
  * avoid losing creation site information for objects made by scripted 'new'.
@@ -1455,24 +1474,15 @@ js::NewObjectWithGroupCommon(JSContext *cx, HandleObjectGroup group, HandleObjec
     if (CanBeFinalizedInBackground(allocKind, group->clasp()))
         allocKind = GetBackgroundAllocKind(allocKind);
 
-    NewObjectCache &cache = cx->runtime()->newObjectCache;
-
-    NewObjectCache::EntryIndex entry = -1;
-    uint64_t gcNumber = 0;
-    if (group->proto().isObject() &&
-        parent == group->proto().toObject()->getParent() &&
-        newKind == GenericObject &&
-        group->clasp()->isNative() &&
-        (!group->newScript() || group->newScript()->analyzed()) &&
-        !cx->compartment()->hasObjectMetadataCallback())
-    {
+    bool isCachable = NewObjectWithGroupIsCachable(cx, group, parent, newKind);
+    if (isCachable) {
+        NewObjectCache &cache = cx->runtime()->newObjectCache;
+        NewObjectCache::EntryIndex entry = -1;
         if (cache.lookupGroup(group, allocKind, &entry)) {
             JSObject *obj = cache.newObjectFromHit(cx, entry,
                                                    GetInitialHeap(newKind, group->clasp()));
             if (obj)
                 return obj;
-        } else {
-            gcNumber = cx->runtime()->gc.gcNumber();
         }
     }
 
@@ -1480,9 +1490,10 @@ js::NewObjectWithGroupCommon(JSContext *cx, HandleObjectGroup group, HandleObjec
     if (!obj)
         return nullptr;
 
-    if (entry != -1 && !obj->as<NativeObject>().hasDynamicSlots() &&
-        cx->runtime()->gc.gcNumber() == gcNumber)
-    {
+    if (isCachable && !obj->as<NativeObject>().hasDynamicSlots()) {
+        NewObjectCache &cache = cx->runtime()->newObjectCache;
+        NewObjectCache::EntryIndex entry = -1;
+        cache.lookupGroup(group, allocKind, &entry);
         cache.fillGroup(entry, group, allocKind, &obj->as<NativeObject>());
     }