Extract pthreadDetection helper. NFC (emscripten-core#26323)

For parity with emscripten-core#26320

Author: sbc100

src/modularize.js

@@ -64,7 +64,7 @@ if (typeof exports === 'object' && typeof module === 'object') {
 // when running in MODULARIZE mode we need use this to know if we should
 // run the module constructor on startup (true only for pthreads).
 #if ENVIRONMENT_MAY_BE_WEB || ENVIRONMENT_MAY_BE_WORKER
-var isPthread = globalThis.self?.name?.startsWith('em-pthread');
+var isPthread = {{{ pthreadDetection() }}};
 #if ENVIRONMENT_MAY_BE_NODE
 // In order to support both web and node we also need to detect node here.
 var isNode = {{{ nodeDetectionCode() }}};

src/parseTools.mjs

@@ -1167,6 +1167,14 @@ function wasmWorkerDetection() {
   }
 }
 
+function pthreadDetection() {
+  if (ASSERTIONS) {
+    return "globalThis.name?.startsWith('em-pthread')";
+  } else {
+    return "globalThis.name == 'em-pthread'";
+  }
+}
+
 function makeExportAliases() {
   var res = ''
   for (var [alias, ex] of Object.entries(nativeAliases)) {
@@ -1253,4 +1261,5 @@ addToCompileTimeContext({
   nodePthreadDetection,
   nodeWWDetection,
   wasmWorkerDetection,
+  pthreadDetection,
 });

src/shell.js

@@ -97,7 +97,7 @@ var ENVIRONMENT_IS_SHELL = !ENVIRONMENT_IS_WEB && !ENVIRONMENT_IS_NODE && !ENVIR
 
 // The way we signal to a worker that it is hosting a pthread is to construct
 // it with a specific name.
-var ENVIRONMENT_IS_PTHREAD = ENVIRONMENT_IS_WORKER && self.name?.startsWith('em-pthread');
+var ENVIRONMENT_IS_PTHREAD = ENVIRONMENT_IS_WORKER && {{{ pthreadDetection() }}}
 
 #if MODULARIZE && ASSERTIONS
 if (ENVIRONMENT_IS_PTHREAD) {

src/shell_minimal.js

@@ -143,7 +143,7 @@ var ENVIRONMENT_IS_WORKER = !!globalThis.WorkerGlobalScope;
 #if PTHREADS
 // MINIMAL_RUNTIME does not support --proxy-to-worker option, so Worker and Pthread environments
 // coincide.
-var ENVIRONMENT_IS_PTHREAD = ENVIRONMENT_IS_WORKER && self.name?.startsWith('em-pthread');
+var ENVIRONMENT_IS_PTHREAD = ENVIRONMENT_IS_WORKER && {{{ pthreadDetection() }}};
 
 #if !MODULARIZE
 // In MODULARIZE mode _scriptName needs to be captured already at the very top of the page immediately when the page is parsed, so it is generated there

test/codesize/test_codesize_minimal_pthreads.json

@@ -1,10 +1,10 @@
 {
-  "a.out.js": 7894,
-  "a.out.js.gz": 3862,
+  "a.out.js": 7888,
+  "a.out.js.gz": 3857,
   "a.out.nodebug.wasm": 19726,
   "a.out.nodebug.wasm.gz": 9135,
-  "total": 27620,
-  "total_gz": 12997,
+  "total": 27614,
+  "total_gz": 12992,
   "sent": [
     "a (memory)",
     "b (emscripten_get_now)",

test/codesize/test_codesize_minimal_pthreads_memgrowth.json

@@ -1,10 +1,10 @@
 {
-  "a.out.js": 8316,
-  "a.out.js.gz": 4063,
+  "a.out.js": 8310,
+  "a.out.js.gz": 4061,
   "a.out.nodebug.wasm": 19727,
   "a.out.nodebug.wasm.gz": 9137,
-  "total": 28043,
-  "total_gz": 13200,
+  "total": 28037,
+  "total_gz": 13198,
   "sent": [
     "a (memory)",
     "b (emscripten_get_now)",