From 0236db0130c6e9b9e5313a080332acb060824264 Mon Sep 17 00:00:00 2001
From: Sam Clegg <sbc@chromium.org>
Date: Mon, 15 Jun 2026 16:07:10 -0700
Subject: [PATCH] Simplify async behaviour of `run` function. NFC

The async/await handling was added in #27059S.  This change simplifies
things by making it the only way to do things.
---
 src/lib/libbrowser.js                            |  4 ++--
 src/lib/libcore.js                               |  3 +++
 src/postamble.js                                 | 16 +++-------------
 test/codesize/test_codesize_cxx_ctors1.json      |  4 ++--
 test/codesize/test_codesize_cxx_ctors2.json      |  8 ++++----
 test/codesize/test_codesize_cxx_except.json      |  8 ++++----
 test/codesize/test_codesize_cxx_except_wasm.json |  8 ++++----
 .../test_codesize_cxx_except_wasm_legacy.json    |  4 ++--
 test/codesize/test_codesize_cxx_lto.json         |  8 ++++----
 test/codesize/test_codesize_cxx_mangle.json      |  8 ++++----
 test/codesize/test_codesize_cxx_noexcept.json    |  4 ++--
 .../test_codesize_file_preload.expected.js       | 10 +++++-----
 test/codesize/test_codesize_file_preload.json    |  8 ++++----
 test/codesize/test_codesize_files_js_fs.json     |  8 ++++----
 test/codesize/test_codesize_hello_dylink.json    |  8 ++++----
 .../codesize/test_codesize_hello_dylink_all.json |  4 ++--
 16 files changed, 53 insertions(+), 60 deletions(-)

diff --git a/src/lib/libbrowser.js b/src/lib/libbrowser.js
index e28324bdb7819..dd33e9fa994a0 100644
--- a/src/lib/libbrowser.js
+++ b/src/lib/libbrowser.js
@@ -614,7 +614,7 @@ var LibraryBrowser = {
   },
 
   // TODO: currently not callable from a pthread, but immediately calls onerror() if not on main thread.
-  emscripten_async_load_script__deps: ['$UTF8ToString', '$runDependencies', '$dependenciesFulfilled'],
+  emscripten_async_load_script__deps: ['$UTF8ToString', '$runDependencies', '$resolveRunDeps'],
   emscripten_async_load_script: async (url, onload, onerror) => {
     url = UTF8ToString(url);
 #if PTHREADS
@@ -634,7 +634,7 @@ var LibraryBrowser = {
       if (onload) {
         var onloadCallback = () => callUserCallback({{{ makeDynCall('v', 'onload') }}});
         if (runDependencies > 0) {
-          dependenciesFulfilled = onloadCallback;
+          resolveRunDeps().then(onloadCallback);
         } else {
           onloadCallback();
         }
diff --git a/src/lib/libcore.js b/src/lib/libcore.js
index e12adf857b47f..81bf30d01a969 100644
--- a/src/lib/libcore.js
+++ b/src/lib/libcore.js
@@ -2266,11 +2266,14 @@ addToLibrary({
   // Note that you can add dependencies in preRun, even though
   // it happens right before run - run will be postponed until
   // the dependencies are met.
+  $runDependencies__deps: ['$resolveRunDeps'],
   $runDependencies__internal: true,
   $runDependencies: 0,
   // overridden to take different actions when all run dependencies are fulfilled
   $dependenciesFulfilled__internal: true,
   $dependenciesFulfilled: null,
+  $resolveRunDeps__internal: true,
+  $resolveRunDeps: () => new Promise((resolve) => dependenciesFulfilled = resolve),
 #if ASSERTIONS
   $runDependencyTracking__internal: true,
   $runDependencyTracking: {},
diff --git a/src/postamble.js b/src/postamble.js
index 430ce3358e150..0dc4e66a2cc07 100644
--- a/src/postamble.js
+++ b/src/postamble.js
@@ -114,19 +114,14 @@ function stackCheckInit() {
 }
 #endif
 
-{{{ asyncIf(MODULARIZE) }}}function run({{{ MAIN_READS_PARAMS ? 'args = programArgs' : '' }}}) {
+{{{ asyncIf(MODULARIZE || '$runDependencies' in addedLibraryItems) }}}function run({{{ MAIN_READS_PARAMS ? 'args = programArgs' : '' }}}) {
 
 #if '$runDependencies' in addedLibraryItems
   if (runDependencies > 0) {
 #if RUNTIME_DEBUG
     dbg('run() called, but dependencies remain, so not running');
 #endif
-#if MODULARIZE
-    await new Promise((resolve) => dependenciesFulfilled = resolve);
-#else
-    dependenciesFulfilled = run;
-    return;
-#endif
+    await resolveRunDeps();
   }
 #endif
 
@@ -149,12 +144,7 @@ function stackCheckInit() {
 #if RUNTIME_DEBUG
     dbg('run() called, but dependencies remain, so not running');
 #endif
-#if MODULARIZE
-    await new Promise((resolve) => dependenciesFulfilled = resolve);
-#else
-    dependenciesFulfilled = run;
-    return;
-#endif
+    await resolveRunDeps();
   }
 #endif
 
diff --git a/test/codesize/test_codesize_cxx_ctors1.json b/test/codesize/test_codesize_cxx_ctors1.json
index fe704633a5333..0150b0e93079c 100644
--- a/test/codesize/test_codesize_cxx_ctors1.json
+++ b/test/codesize/test_codesize_cxx_ctors1.json
@@ -1,9 +1,9 @@
 {
-  "a.out.js": 19192,
+  "a.out.js": 19198,
   "a.out.js.gz": 7944,
   "a.out.nodebug.wasm": 132666,
   "a.out.nodebug.wasm.gz": 49962,
-  "total": 151858,
+  "total": 151864,
   "total_gz": 57906,
   "sent": [
     "__cxa_throw",
diff --git a/test/codesize/test_codesize_cxx_ctors2.json b/test/codesize/test_codesize_cxx_ctors2.json
index abaec01958ad3..375d8dcff39ff 100644
--- a/test/codesize/test_codesize_cxx_ctors2.json
+++ b/test/codesize/test_codesize_cxx_ctors2.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 19169,
-  "a.out.js.gz": 7931,
+  "a.out.js": 19175,
+  "a.out.js.gz": 7932,
   "a.out.nodebug.wasm": 132092,
   "a.out.nodebug.wasm.gz": 49625,
-  "total": 151261,
-  "total_gz": 57556,
+  "total": 151267,
+  "total_gz": 57557,
   "sent": [
     "__cxa_throw",
     "_abort_js",
diff --git a/test/codesize/test_codesize_cxx_except.json b/test/codesize/test_codesize_cxx_except.json
index 539d488994e3c..4e19d807a27fa 100644
--- a/test/codesize/test_codesize_cxx_except.json
+++ b/test/codesize/test_codesize_cxx_except.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 23166,
-  "a.out.js.gz": 8928,
+  "a.out.js": 23172,
+  "a.out.js.gz": 8931,
   "a.out.nodebug.wasm": 172586,
   "a.out.nodebug.wasm.gz": 57501,
-  "total": 195752,
-  "total_gz": 66429,
+  "total": 195758,
+  "total_gz": 66432,
   "sent": [
     "__cxa_begin_catch",
     "__cxa_end_catch",
diff --git a/test/codesize/test_codesize_cxx_except_wasm.json b/test/codesize/test_codesize_cxx_except_wasm.json
index 9b062493420b1..dfe04efe1b0aa 100644
--- a/test/codesize/test_codesize_cxx_except_wasm.json
+++ b/test/codesize/test_codesize_cxx_except_wasm.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 18995,
-  "a.out.js.gz": 7862,
+  "a.out.js": 19000,
+  "a.out.js.gz": 7863,
   "a.out.nodebug.wasm": 147991,
   "a.out.nodebug.wasm.gz": 55370,
-  "total": 166986,
-  "total_gz": 63232,
+  "total": 166991,
+  "total_gz": 63233,
   "sent": [
     "_abort_js",
     "_tzset_js",
diff --git a/test/codesize/test_codesize_cxx_except_wasm_legacy.json b/test/codesize/test_codesize_cxx_except_wasm_legacy.json
index ff7f4134c2ad4..cb97d37c0f808 100644
--- a/test/codesize/test_codesize_cxx_except_wasm_legacy.json
+++ b/test/codesize/test_codesize_cxx_except_wasm_legacy.json
@@ -1,9 +1,9 @@
 {
-  "a.out.js": 19069,
+  "a.out.js": 19074,
   "a.out.js.gz": 7884,
   "a.out.nodebug.wasm": 145797,
   "a.out.nodebug.wasm.gz": 54992,
-  "total": 164866,
+  "total": 164871,
   "total_gz": 62876,
   "sent": [
     "_abort_js",
diff --git a/test/codesize/test_codesize_cxx_lto.json b/test/codesize/test_codesize_cxx_lto.json
index 6f6b2e32a7dbd..62d07de850976 100644
--- a/test/codesize/test_codesize_cxx_lto.json
+++ b/test/codesize/test_codesize_cxx_lto.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 18532,
-  "a.out.js.gz": 7634,
+  "a.out.js": 18538,
+  "a.out.js.gz": 7635,
   "a.out.nodebug.wasm": 102168,
   "a.out.nodebug.wasm.gz": 39572,
-  "total": 120700,
-  "total_gz": 47206,
+  "total": 120706,
+  "total_gz": 47207,
   "sent": [
     "a (emscripten_resize_heap)",
     "b (_setitimer_js)",
diff --git a/test/codesize/test_codesize_cxx_mangle.json b/test/codesize/test_codesize_cxx_mangle.json
index 51ef69417916e..5c23ad70756ea 100644
--- a/test/codesize/test_codesize_cxx_mangle.json
+++ b/test/codesize/test_codesize_cxx_mangle.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 23216,
-  "a.out.js.gz": 8947,
+  "a.out.js": 23222,
+  "a.out.js.gz": 8951,
   "a.out.nodebug.wasm": 239015,
   "a.out.nodebug.wasm.gz": 79854,
-  "total": 262231,
-  "total_gz": 88801,
+  "total": 262237,
+  "total_gz": 88805,
   "sent": [
     "__cxa_begin_catch",
     "__cxa_end_catch",
diff --git a/test/codesize/test_codesize_cxx_noexcept.json b/test/codesize/test_codesize_cxx_noexcept.json
index 8e421f324deb9..3d61a03f35854 100644
--- a/test/codesize/test_codesize_cxx_noexcept.json
+++ b/test/codesize/test_codesize_cxx_noexcept.json
@@ -1,9 +1,9 @@
 {
-  "a.out.js": 19192,
+  "a.out.js": 19198,
   "a.out.js.gz": 7944,
   "a.out.nodebug.wasm": 134666,
   "a.out.nodebug.wasm.gz": 50806,
-  "total": 153858,
+  "total": 153864,
   "total_gz": 58750,
   "sent": [
     "__cxa_throw",
diff --git a/test/codesize/test_codesize_file_preload.expected.js b/test/codesize/test_codesize_file_preload.expected.js
index dc412229c2187..e31edf81ddd55 100644
--- a/test/codesize/test_codesize_file_preload.expected.js
+++ b/test/codesize/test_codesize_file_preload.expected.js
@@ -1304,6 +1304,8 @@ var FS_createDataFile = (...args) => FS.createDataFile(...args);
 
 var getUniqueRunDependency = id => id;
 
+var resolveRunDeps = () => new Promise(resolve => dependenciesFulfilled = resolve);
+
 var runDependencies = 0;
 
 var dependenciesFulfilled = null;
@@ -3177,16 +3179,14 @@ function callMain() {
   }
 }
 
-function run() {
+async function run() {
   if (runDependencies > 0) {
-    dependenciesFulfilled = run;
-    return;
+    await resolveRunDeps();
   }
   preRun();
   // a preRun added a dependency, run will be called later
   if (runDependencies > 0) {
-    dependenciesFulfilled = run;
-    return;
+    await resolveRunDeps();
   }
   function doRun() {
     // run may have just been called through dependencies being fulfilled just in this very frame,
diff --git a/test/codesize/test_codesize_file_preload.json b/test/codesize/test_codesize_file_preload.json
index d4e588abd444b..5651ce9b1412a 100644
--- a/test/codesize/test_codesize_file_preload.json
+++ b/test/codesize/test_codesize_file_preload.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 22108,
-  "a.out.js.gz": 9183,
+  "a.out.js": 22138,
+  "a.out.js.gz": 9194,
   "a.out.nodebug.wasm": 1666,
   "a.out.nodebug.wasm.gz": 945,
-  "total": 23774,
-  "total_gz": 10128,
+  "total": 23804,
+  "total_gz": 10139,
   "sent": [
     "a (fd_write)"
   ],
diff --git a/test/codesize/test_codesize_files_js_fs.json b/test/codesize/test_codesize_files_js_fs.json
index ab61cf55c9fa7..30bd03a070237 100644
--- a/test/codesize/test_codesize_files_js_fs.json
+++ b/test/codesize/test_codesize_files_js_fs.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 17840,
-  "a.out.js.gz": 7285,
+  "a.out.js": 17846,
+  "a.out.js.gz": 7286,
   "a.out.nodebug.wasm": 381,
   "a.out.nodebug.wasm.gz": 260,
-  "total": 18221,
-  "total_gz": 7545,
+  "total": 18227,
+  "total_gz": 7546,
   "sent": [
     "a (fd_write)",
     "b (fd_read)",
diff --git a/test/codesize/test_codesize_hello_dylink.json b/test/codesize/test_codesize_hello_dylink.json
index f654bb7291bba..f98e09a213ca2 100644
--- a/test/codesize/test_codesize_hello_dylink.json
+++ b/test/codesize/test_codesize_hello_dylink.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 26265,
-  "a.out.js.gz": 11182,
+  "a.out.js": 26271,
+  "a.out.js.gz": 11181,
   "a.out.nodebug.wasm": 17861,
   "a.out.nodebug.wasm.gz": 9019,
-  "total": 44126,
-  "total_gz": 20201,
+  "total": 44132,
+  "total_gz": 20200,
   "sent": [
     "__syscall_stat64",
     "emscripten_resize_heap",
diff --git a/test/codesize/test_codesize_hello_dylink_all.json b/test/codesize/test_codesize_hello_dylink_all.json
index 584a099573a66..2edf7acca41c7 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": 268274,
+  "a.out.js": 268334,
   "a.out.nodebug.wasm": 587640,
-  "total": 855914,
+  "total": 855974,
   "sent": [
     "IMG_Init",
     "IMG_Load",