From d4d07233dcbac4228051f3345c72ab3309d0c606 Mon Sep 17 00:00:00 2001
From: Pawel Kozlowski <pkozlowski.opensource@gmail.com>
Date: Fri, 11 Oct 2019 16:38:07 +0200
Subject: [PATCH] perf(ivy): guard host binding execution with a TNode flag
 (#33102)

Based on the results of the `directive_instantiate` executing host
bindings logic (in creation mode) account for ~23% of time spent in
the directive instantiation, even if a directive doesn't have host
bindings! This is clearly wastful hence a new flag.

PR Close #33102
---
 .../src/render3/instructions/lview_debug.ts   |  1 +
 .../core/src/render3/instructions/shared.ts   |  9 ++++----
 packages/core/src/render3/interfaces/node.ts  | 23 ++++++++++++-------
 3 files changed, 21 insertions(+), 12 deletions(-)

diff --git a/packages/core/src/render3/instructions/lview_debug.ts b/packages/core/src/render3/instructions/lview_debug.ts
index 362e678c98..1b99765ad3 100644
--- a/packages/core/src/render3/instructions/lview_debug.ts
+++ b/packages/core/src/render3/instructions/lview_debug.ts
@@ -164,6 +164,7 @@ export const TNodeConstructor = class TNode implements ITNode {
     if (this.flags & TNodeFlags.hasContentQuery) flags.push('TNodeFlags.hasContentQuery');
     if (this.flags & TNodeFlags.hasStyleInput) flags.push('TNodeFlags.hasStyleInput');
     if (this.flags & TNodeFlags.hasInitialStyling) flags.push('TNodeFlags.hasInitialStyling');
+    if (this.flags & TNodeFlags.hasHostBindings) flags.push('TNodeFlags.hasHostBindings');
     if (this.flags & TNodeFlags.isComponentHost) flags.push('TNodeFlags.isComponentHost');
     if (this.flags & TNodeFlags.isDirectiveHost) flags.push('TNodeFlags.isDirectiveHost');
     if (this.flags & TNodeFlags.isDetached) flags.push('TNodeFlags.isDetached');
diff --git a/packages/core/src/render3/instructions/shared.ts b/packages/core/src/render3/instructions/shared.ts
index 2ca04d1a48..5d21b2ba90 100644
--- a/packages/core/src/render3/instructions/shared.ts
+++ b/packages/core/src/render3/instructions/shared.ts
@@ -536,7 +536,9 @@ export function createDirectivesInstances(
     tView: TView, lView: LView, tNode: TElementNode | TContainerNode | TElementContainerNode) {
   if (!getBindingsEnabled()) return;
   instantiateAllDirectives(tView, lView, tNode);
-  invokeDirectivesHostBindings(tView, lView, tNode);
+  if ((tNode.flags & TNodeFlags.hasHostBindings) === TNodeFlags.hasHostBindings) {
+    invokeDirectivesHostBindings(tView, lView, tNode);
+  }
   setActiveHostElement(null);
 }
 
@@ -1069,9 +1071,8 @@ export function resolveDirectives(
 
       saveNameToExportMap(tView.data !.length - 1, def, exportsMap);
 
-      if (def.contentQueries) {
-        tNode.flags |= TNodeFlags.hasContentQuery;
-      }
+      if (def.contentQueries !== null) tNode.flags |= TNodeFlags.hasContentQuery;
+      if (def.hostBindings !== null) tNode.flags |= TNodeFlags.hasHostBindings;
 
       // Init hooks are queued now so ngOnInit is called in host components before
       // any projected components.
diff --git a/packages/core/src/render3/interfaces/node.ts b/packages/core/src/render3/interfaces/node.ts
index 688784124c..a598252390 100644
--- a/packages/core/src/render3/interfaces/node.ts
+++ b/packages/core/src/render3/interfaces/node.ts
@@ -46,30 +46,37 @@ export const enum TNodeType {
  */
 export const enum TNodeFlags {
   /** This bit is set if the node is a host for any directive (including a component) */
-  isDirectiveHost = 0b00000001,
+  isDirectiveHost = 0b000000001,
 
   /**
    * This bit is set if the node is a host for a component. Setting this bit implies that the
    * isDirectiveHost bit is set as well. */
-  isComponentHost = 0b00000010,
+  isComponentHost = 0b000000010,
 
   /** This bit is set if the node has been projected */
-  isProjected = 0b00000100,
+  isProjected = 0b000000100,
 
   /** This bit is set if any directive on this node has content queries */
-  hasContentQuery = 0b00001000,
+  hasContentQuery = 0b000001000,
 
   /** This bit is set if the node has any "class" inputs */
-  hasClassInput = 0b00010000,
+  hasClassInput = 0b000010000,
 
   /** This bit is set if the node has any "style" inputs */
-  hasStyleInput = 0b00100000,
+  hasStyleInput = 0b000100000,
 
   /** This bit is set if the node has initial styling */
-  hasInitialStyling = 0b01000000,
+  hasInitialStyling = 0b001000000,
 
   /** This bit is set if the node has been detached by i18n */
-  isDetached = 0b10000000,
+  isDetached = 0b010000000,
+
+  /**
+   * This bit is set if the node has directives with host bindings. This flags allows us to guard
+   * host-binding logic and invoke it only on nodes that actually have directives with host
+   * bindings.
+   */
+  hasHostBindings = 0b100000000,
 }
 
 /**