From 59e487d30cf7855ce6540c5562b723591280049f Mon Sep 17 00:00:00 2001
From: Aarni Koskela <akx@iki.fi>
Date: Tue, 30 May 2023 04:39:19 +0300
Subject: [PATCH] Optimize frontend's is_dep calls (#4334)

* Optimize is_dep (36 to 12 msec)

* Call is_dep less (12 msec to 9 msec)

* Changelog

---------

Co-authored-by: pngwn <hello@pngwn.io>
---
 CHANGELOG.md             |  2 +-
 js/app/src/Blocks.svelte | 40 ++++++++++++++--------------------------
 2 files changed, 15 insertions(+), 27 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e472419714..09e5538fbe 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,7 +10,7 @@ No changes to highlight.
 
 ## Other Changes:
 
-No changes to highlight.
+- Performance optimization in the frontend's Blocks code by [@akx](https://github.com/akx) in [PR 4334](https://github.com/gradio-app/gradio/pull/4334)
 
 ## Breaking Changes:
 
diff --git a/js/app/src/Blocks.svelte b/js/app/src/Blocks.svelte
index 303de144a1..0fc328764b 100644
--- a/js/app/src/Blocks.svelte
+++ b/js/app/src/Blocks.svelte
@@ -94,38 +94,26 @@
 		type: "inputs" | "outputs",
 		deps: Array<Dependency>
 	) {
-		let dep_index = 0;
-		for (;;) {
-			const dep = deps[dep_index];
-			if (dep === undefined) break;
-
-			let dep_item_index = 0;
-			for (;;) {
-				const dep_item = dep[type][dep_item_index];
-				if (dep_item === undefined) break;
+		for (const dep of deps) {
+			for (const dep_item of dep[type]) {
 				if (dep_item === id) return true;
-				dep_item_index++;
 			}
-
-			dep_index++;
 		}
-
 		return false;
 	}
 
-	const dynamic_ids: Set<number> = components.reduce<Set<number>>(
-		(acc, { id, props }) => {
-			const is_input = is_dep(id, "inputs", dependencies);
-			const is_output = is_dep(id, "outputs", dependencies);
-
-			if (!is_input && !is_output && has_no_default_value(props?.value))
-				acc.add(id); // default dynamic
-			if (is_input) acc.add(id);
-
-			return acc;
-		},
-		new Set()
-	);
+	const dynamic_ids: Set<number> = new Set();
+	for (const comp of components) {
+		const { id, props } = comp;
+		const is_input = is_dep(id, "inputs", dependencies);
+		if (
+			is_input ||
+			(!is_dep(id, "outputs", dependencies) &&
+				has_no_default_value(props?.value))
+		) {
+			dynamic_ids.add(id);
+		}
+	}
 
 	function has_no_default_value(value: any) {
 		return (