From bad1ed9921edf75c962e9df3f7fab898ddc0cebc Mon Sep 17 00:00:00 2001
From: Sam Clegg <sbc@chromium.org>
Date: Mon, 15 Jun 2026 23:43:28 -0700
Subject: [PATCH] Convert Browser.workers to HandleAllocator (using
 workerHandles global)

This avoids using a raw array and allows reusing IDs.
Remove Browser.workers and use a new global helper workerHandles instead.
---
 src/lib/libbrowser.js                         | 33 +++++++++++--------
 .../test_codesize_hello_dylink_all.json       |  4 +--
 2 files changed, 21 insertions(+), 16 deletions(-)

diff --git a/src/lib/libbrowser.js b/src/lib/libbrowser.js
index 8b064d4720bbb..fc5006c7ee2e8 100644
--- a/src/lib/libbrowser.js
+++ b/src/lib/libbrowser.js
@@ -6,6 +6,10 @@
 
 // Utilities for browser environments
 var LibraryBrowser = {
+  $workerHandles__internal: true,
+  $workerHandles__deps: ['$HandleAllocator'],
+  $workerHandles: 'new HandleAllocator();',
+
   $Browser__deps: [
     '$callUserCallback',
     '$getFullscreenElement',
@@ -24,7 +28,6 @@ var LibraryBrowser = {
     isFullscreen: false,
     pointerLock: false,
     moduleContextCreatedCallbacks: [],
-    workers: [],
     preloadedImages: {},
     preloadedAudios: {},
 
@@ -717,20 +720,21 @@ var LibraryBrowser = {
 
   // To avoid creating worker parent->child chains, always proxies to execute on the main thread.
   emscripten_create_worker__proxy: 'sync',
-  emscripten_create_worker__deps: ['$UTF8ToString', 'realloc'],
+  emscripten_create_worker__deps: ['$UTF8ToString', 'realloc', '$workerHandles'],
   emscripten_create_worker: (url) => {
     url = UTF8ToString(url);
-    var id = Browser.workers.length;
+    var worker = new Worker(url);
     var info = {
-      worker: new Worker(url),
+      worker,
       callbacks: [],
       awaited: 0,
       buffer: 0,
     };
-    info.worker.onmessage = (msg) => {
+    var id = workerHandles.allocate(info);
+    worker.onmessage = (msg) => {
       if (ABORT) return;
-      var info = Browser.workers[id];
-      if (!info) return; // worker was destroyed meanwhile
+      if (!workerHandles.has(id)) return; // worker was destroyed meanwhile
+      var info = workerHandles.get(id);
       var callbackId = msg.data['callbackId'];
       var callbackInfo = info.callbacks[callbackId];
       if (!callbackInfo) return; // no callback or callback removed meanwhile
@@ -750,23 +754,23 @@ var LibraryBrowser = {
         callbackInfo.func(0, 0, callbackInfo.arg);
       }
     };
-    Browser.workers.push(info);
     return id;
   },
 
-  emscripten_destroy_worker__deps: ['free'],
+  emscripten_destroy_worker__deps: ['free', '$workerHandles'],
   emscripten_destroy_worker__proxy: 'sync',
   emscripten_destroy_worker: (id) => {
-    var info = Browser.workers[id];
+    var info = workerHandles.get(id);
     info.worker.terminate();
     _free(info.buffer);
-    Browser.workers[id] = null;
+    workerHandles.free(id);
   },
 
+  emscripten_call_worker__deps: ['$workerHandles'],
   emscripten_call_worker__proxy: 'sync',
   emscripten_call_worker: (id, funcName, data, size, callback, arg) => {
     funcName = UTF8ToString(funcName);
-    var info = Browser.workers[id];
+    var info = workerHandles.get(id);
     var callbackId = -1;
     if (callback) {
       // If we are waiting for a response from the worker we need to keep
@@ -826,10 +830,11 @@ var LibraryBrowser = {
   },
 #endif
 
+  emscripten_get_worker_queue_size__deps: ['$workerHandles'],
   emscripten_get_worker_queue_size__proxy: 'sync',
   emscripten_get_worker_queue_size: (id) => {
-    var info = Browser.workers[id];
-    if (!info) return -1;
+    if (!workerHandles.has(id)) return -1;
+    var info = workerHandles.get(id);
     return info.awaited;
   },
 
diff --git a/test/codesize/test_codesize_hello_dylink_all.json b/test/codesize/test_codesize_hello_dylink_all.json
index 0edbd7132a11b..037a8bdea161d 100644
--- a/test/codesize/test_codesize_hello_dylink_all.json
+++ b/test/codesize/test_codesize_hello_dylink_all.json
@@ -1,7 +1,7 @@
 {
-  "a.out.js": 268247,
+  "a.out.js": 268245,
   "a.out.nodebug.wasm": 587640,
-  "total": 855887,
+  "total": 855885,
   "sent": [
     "IMG_Init",
     "IMG_Load",