Update Props during pre-allocation avoiding re-updating the same props during mounting

Summary:
Update Props during pre-allocation avoiding re-updating the same props during mounting

MobileLab test showed an improvement of:
MARKETPLACE_YOU_TTI_SUCCESS: -3.34% = 58ms

Reviewed By: shergin

Differential Revision: D14252170

fbshipit-source-id: 1f4e9ad5dcecbc06651fa065135ffeed4892d984

ReactAndroid/src/main/java/com/facebook/react/fabric/FabricUIManager.java

@@ -21,7 +21,6 @@ import android.support.annotation.UiThread;
 import android.util.Log;
 import android.view.View;
 import com.facebook.common.logging.FLog;
-import com.facebook.infer.annotation.Assertions;
 import com.facebook.infer.annotation.ThreadConfined;
 import com.facebook.proguard.annotations.DoNotStrip;
 import com.facebook.react.bridge.LifecycleEventListener;
@@ -73,6 +72,7 @@ public class FabricUIManager implements UIManager, LifecycleEventListener {
   private static final Map<String, String> sComponentNames = new HashMap<>();
   private static final int FRAME_TIME_MS = 16;
   private static final int MAX_TIME_IN_FRAME_FOR_NON_BATCHED_OPERATIONS_MS = 8;
+  private static final int PRE_MOUNT_ITEMS_INITIAL_SIZE_ARRAY = 250;
 
   static {
     FabricSoLoader.staticInit();
@@ -105,7 +105,8 @@ public class FabricUIManager implements UIManager, LifecycleEventListener {
   private List<MountItem> mMountItems = new ArrayList<>();
 
   @GuardedBy("mPreMountItemsLock")
-  private ArrayDeque<MountItem> mPreMountItems = new ArrayDeque<>();
+  private ArrayDeque<MountItem> mPreMountItems = new ArrayDeque<>(
+    PRE_MOUNT_ITEMS_INITIAL_SIZE_ARRAY);
 
   @ThreadConfined(UI)
   private final DispatchUIFrameCallback mDispatchUIFrameCallback;
@@ -165,7 +166,7 @@ public class FabricUIManager implements UIManager, LifecycleEventListener {
   @DoNotStrip
   @SuppressWarnings("unused")
   private MountItem createMountItem(
-      String componentName, int reactRootTag, int reactTag, boolean isVirtual) {
+      String componentName, int reactRootTag, int reactTag, boolean isVirtual, ReadableMap props) {
     String component = sComponentNames.get(componentName);
     if (component == null) {
       throw new IllegalArgumentException("Unable to find component with name " + componentName);
@@ -174,7 +175,7 @@ public class FabricUIManager implements UIManager, LifecycleEventListener {
     if (reactContext == null) {
       throw new IllegalArgumentException("Unable to find ReactContext for root: " + reactRootTag);
     }
-    return new CreateMountItem(reactContext, component, reactTag, isVirtual);
+    return new CreateMountItem(reactContext, component, reactTag, isVirtual, props);
   }
 
   @Override
@@ -197,11 +198,10 @@ public class FabricUIManager implements UIManager, LifecycleEventListener {
       // There is no reason to allocate views ahead of time on the main thread.
       return;
     }
+
+    ThemedReactContext context = mReactContextForRootTag.get(rootTag);
+    String component = sComponentNames.get(componentName);
     synchronized (mPreMountItemsLock) {
-      ThemedReactContext context =
-        Assertions.assertNotNull(mReactContextForRootTag.get(rootTag));
-      String component = sComponentNames.get(componentName);
-      Assertions.assertNotNull(component);
       mPreMountItems.add(new PreAllocateViewMountItem(context, rootTag, reactTag, component, props));
     }
   }
@@ -315,6 +315,9 @@ public class FabricUIManager implements UIManager, LifecycleEventListener {
     mRunStartTime = SystemClock.uptimeMillis();
     List<MountItem> mountItemsToDispatch;
     synchronized (mMountItemsLock) {
+      if (mMountItems.isEmpty()) {
+        return;
+      }
       mountItemsToDispatch = mMountItems;
       mMountItems = new ArrayList<>();
     }

ReactAndroid/src/main/java/com/facebook/react/fabric/jsi/jni/Binding.cpp

@@ -173,7 +173,7 @@ local_ref<JMountItem::javaobject> createCreateMountItem(
     const Tag rootTag) {
   static auto createJavaInstruction =
       jni::findClassStatic(UIManagerJavaDescriptor)
-          ->getMethod<alias_ref<JMountItem>(jstring, jint, jint, jboolean)>(
+          ->getMethod<alias_ref<JMountItem>(jstring, jint, jint, jboolean, ReadableMap::javaobject)>(
               "createMountItem");
 
   auto newChildShadowView = mutation.newChildShadowView;
@@ -183,12 +183,16 @@ local_ref<JMountItem::javaobject> createCreateMountItem(
 
   jboolean isVirtual = newChildShadowView.layoutMetrics == EmptyLayoutMetrics;
 
+  local_ref<ReadableMap::javaobject> props = isVirtual ? nullptr :
+        castReadableMap(ReadableNativeMap::newObjectCxxArgs(newChildShadowView.props->rawProps));
+
   return createJavaInstruction(
       javaUIManager,
       componentName.get(),
       rootTag,
       newChildShadowView.tag,
-      isVirtual);
+      isVirtual,
+      props != nullptr ? props.get() : nullptr);
 }
 
 local_ref<JMountItem::javaobject> createUpdateEventEmitterMountItem(
@@ -402,7 +406,7 @@ void Binding::schedulerDidFinishTransaction(
           mountItems[position++] =
               createInsertMountItem(javaUIManager_, mutation);
 
-          if (mutation.newChildShadowView.props->revision != 0) {
+          if (mutation.newChildShadowView.props->revision > 1) {
             mountItems[position++] =
                 createUpdatePropsMountItem(javaUIManager_, mutation);
           }
@@ -465,20 +469,16 @@ void Binding::schedulerDidRequestPreliminaryViewAllocation(
     const SurfaceId surfaceId,
     bool isLayoutable,
     const ShadowView &shadowView) {
+
   if (isLayoutable) {
     static auto preallocateView =
         jni::findClassStatic(UIManagerJavaDescriptor)
             ->getMethod<void(jint, jint, jstring, ReadableMap::javaobject)>("preallocateView");
 
-    if (shadowView.props->rawProps.isNull()) {
-      local_ref<ReadableMap::javaobject> readableMap =
-          castReadableMap(ReadableNativeMap::newObjectCxxArgs(shadowView.props->rawProps));
-      preallocateView(
-          javaUIManager_, surfaceId, shadowView.tag, make_jstring(shadowView.componentName).get(), readableMap.get());
-    } else {
-      preallocateView(
-          javaUIManager_, surfaceId, shadowView.tag, make_jstring(shadowView.componentName).get(), nullptr);
-    }
+    local_ref<ReadableMap::javaobject> readableMap =
+        castReadableMap(ReadableNativeMap::newObjectCxxArgs(shadowView.props->rawProps));
+    preallocateView(
+        javaUIManager_, surfaceId, shadowView.tag, make_jstring(shadowView.componentName).get(), readableMap.get());
   }
 }
 

ReactAndroid/src/main/java/com/facebook/react/fabric/mounting/MountingManager.java

@@ -168,8 +168,8 @@ public class MountingManager {
       ThemedReactContext themedReactContext,
       String componentName,
       int reactTag,
+
       boolean isVirtual) {
-    UiThreadUtil.assertOnUiThread();
     View view = null;
     ViewManager viewManager = null;
 
@@ -280,10 +280,11 @@ public class MountingManager {
     String componentName,
     int reactTag,
     ReadableMap props) {
+
+    if (mTagToViewState.get(reactTag) != null) return;
+
     createView(reactContext, componentName, reactTag, false);
-    if (props != null) {
-      updateProps(reactTag, props);
-    }
+    updateProps(reactTag, props);
   }
 
   @UiThread

ReactAndroid/src/main/java/com/facebook/react/fabric/mounting/mountitems/CreateMountItem.java

@@ -6,6 +6,7 @@
  */
 package com.facebook.react.fabric.mounting.mountitems;
 
+import com.facebook.react.bridge.ReadableMap;
 import com.facebook.react.fabric.mounting.MountingManager;
 import com.facebook.react.uimanager.ThemedReactContext;
 
@@ -15,21 +16,27 @@ public class CreateMountItem implements MountItem {
   private final int mReactTag;
   private final ThemedReactContext mThemedReactContext;
   private final boolean mIsVirtual;
+  private final ReadableMap mProps;
 
   public CreateMountItem(
       ThemedReactContext themedReactContext,
       String componentName,
       int reactTag,
-      boolean isVirtual) {
+      boolean isVirtual,
+      ReadableMap props) {
     mReactTag = reactTag;
     mThemedReactContext = themedReactContext;
     mComponentName = componentName;
     mIsVirtual = isVirtual;
+    mProps = props;
   }
 
   @Override
   public void execute(MountingManager mountingManager) {
     mountingManager.createView(mThemedReactContext, mComponentName, mReactTag, mIsVirtual);
+    if (mProps != null && !mIsVirtual) {
+      mountingManager.updateProps(mReactTag, mProps);
+    }
   }
 
   public String getComponentName() {