Extract startWorker helper. NFC (#18313)

Author: RReverser

src/closure-externs/closure-externs.js

@@ -18,6 +18,12 @@ var EMSCRIPTEN$AWAIT$IMPORT;
 // Don't minify createRequire
 var createRequire;
 
+// Don't minify startWorker which we use to start workers once the runtime is ready.
+/**
+ * @param {Object} Module
+ */
+var startWorker = function(Module) {};
+
 // Closure externs used by library_sockfs.js
 
 /**

src/postamble.js

@@ -292,7 +292,7 @@ function run(args) {
     readyPromiseResolve(Module);
 #endif // MODULARIZE
     initRuntime();
-    postMessage({ 'cmd': 'loaded' });
+    startWorker(Module);
     return;
   }
 #endif

src/postamble_minimal.js

@@ -246,13 +246,6 @@ WebAssembly.instantiate(Module['wasm'], imports).then(function(output) {
 #else
   ready();
 #endif
-
-#if USE_PTHREADS
-  // This Worker is now ready to host pthreads, tell the main thread we can proceed.
-  if (ENVIRONMENT_IS_PTHREAD) {
-    postMessage({ 'cmd': 'loaded' });
-  }
-#endif
 }
 
 #if ASSERTIONS || WASM == 2

src/shell_minimal.js

@@ -119,6 +119,12 @@ function ready() {
 #elif ASSERTIONS
   out('ready() called, and INVOKE_RUN=0. The runtime is now ready for you to call run() to invoke application _main(). You can also override ready() in a --pre-js file to get this signal as a callback')
 #endif
+#if USE_PTHREADS
+  // This Worker is now ready to host pthreads, tell the main thread we can proceed.
+  if (ENVIRONMENT_IS_PTHREAD) {
+    startWorker(Module);
+  }
+#endif
 }
 
 #if POLYFILL

src/worker.js

@@ -114,6 +114,15 @@ self.onunhandledrejection = (e) => {
   throw e.reason ?? e;
 };
 
+// Add a callback for when the runtime is initialized.
+self.startWorker = (instance) => {
+#if MODULARIZE
+  Module = instance;
+#endif
+  // Notify the main thread that this thread has loaded.
+  postMessage({ 'cmd': 'loaded' });
+};
+
 self.onmessage = (e) => {
   try {
     if (e.data.cmd === 'load') { // Preload command that is called once per worker to parse and load the Emscripten code.
@@ -167,11 +176,8 @@ self.onmessage = (e) => {
 #endif
 
 #if MODULARIZE && EXPORT_ES6
-      (e.data.urlOrBlob ? import(e.data.urlOrBlob) : import('./{{{ TARGET_JS_NAME }}}')).then(function(exports) {
-        return exports.default(Module);
-      }).then(function(instance) {
-        Module = instance;
-      });
+      (e.data.urlOrBlob ? import(e.data.urlOrBlob) : import('./{{{ TARGET_JS_NAME }}}'))
+      .then(exports => exports.default(Module));
 #else
       if (typeof e.data.urlOrBlob == 'string') {
 #if TRUSTED_TYPES
@@ -194,13 +200,9 @@ self.onmessage = (e) => {
       }
 #if MODULARIZE
 #if MINIMAL_RUNTIME
-      {{{ EXPORT_NAME }}}(imports).then(function (instance) {
-        Module = instance;
-      });
+      {{{ EXPORT_NAME }}}(imports);
 #else
-      {{{ EXPORT_NAME }}}(Module).then(function (instance) {
-        Module = instance;
-      });
+      {{{ EXPORT_NAME }}}(Module);
 #endif
 #endif
 #endif // MODULARIZE && EXPORT_ES6