Remove some unnecessary use of EMSCRIPTEN_KEEPALIVE. NFC (#20604)

Author: sbc100

emcc.py

@@ -1767,6 +1767,8 @@ def setup_pthreads(target):
     '_pthread_self',
     'checkMailbox',
   ]
+  if settings.EMBIND:
+    worker_imports.append('__embind_initialize_bindings')
   settings.EXPORTED_FUNCTIONS += worker_imports
   building.user_requested_exports.update(worker_imports)
 
@@ -2497,6 +2499,9 @@ def phase_linker_setup(options, state, newargs):
     # overrides that.
     default_setting('ABORTING_MALLOC', 0)
 
+  if '-lembind' in [x for _, x in state.link_flags]:
+    settings.EMBIND = 1
+
   if settings.PTHREADS:
     setup_pthreads(target)
     settings.JS_LIBRARIES.append((0, 'library_pthread.js'))
@@ -2615,9 +2620,6 @@ def check_memory_setting(setting):
   if not settings.DECLARE_ASM_MODULE_EXPORTS or '-lexports.js' in [x for _, x in state.link_flags]:
     settings.MINIFY_WASM_EXPORT_NAMES = 0
 
-  if '-lembind' in [x for _, x in state.link_flags]:
-    settings.EMBIND = 1
-
   # Enable minification of wasm imports and exports when appropriate, if we
   # are emitting an optimized JS+wasm combo (then the JS knows how to load the minified names).
   # Things that process the JS after this operation would be done must disable this.

src/library_pthread.js

@@ -1243,6 +1243,7 @@ var LibraryPThread = {
 #endif // MAIN_MODULE
 
   $checkMailbox__deps: ['$callUserCallback',
+                        '_emscripten_check_mailbox',
                         '_emscripten_thread_mailbox_await'],
   $checkMailbox: () => {
     // Only check the mailbox if we have a live pthread runtime. We implement

system/lib/embind/bind.cpp

@@ -20,7 +20,8 @@ using namespace emscripten;
 using namespace internal;
 
 extern "C" {
-const char* EMSCRIPTEN_KEEPALIVE __getTypeName(const std::type_info* ti) {
+
+const char* __getTypeName(const std::type_info* ti) {
   if (has_unbound_type_names) {
 #ifdef USE_CXA_DEMANGLE
     int stat;
@@ -51,7 +52,7 @@ const char* EMSCRIPTEN_KEEPALIVE __getTypeName(const std::type_info* ti) {
 
 static InitFunc* init_funcs = nullptr;
 
-EMSCRIPTEN_KEEPALIVE void _embind_initialize_bindings() {
+void _embind_initialize_bindings() {
   for (auto* f = init_funcs; f; f = f->next) {
     f->init_func();
   }

system/lib/gl/webgl1.c

@@ -73,7 +73,7 @@ EMSCRIPTEN_WEBGL_CONTEXT_HANDLE emscripten_webgl_get_current_context(void) {
   return (EMSCRIPTEN_WEBGL_CONTEXT_HANDLE)pthread_getspecific(currentActiveWebGLContext);
 }
 
-EMSCRIPTEN_RESULT EMSCRIPTEN_KEEPALIVE emscripten_webgl_commit_frame(void) {
+EMSCRIPTEN_RESULT emscripten_webgl_commit_frame(void) {
   GL_FUNCTION_TRACE(__func__);
   if (pthread_getspecific(currentThreadOwnsItsWebGLContext))
     return emscripten_webgl_do_commit_frame();

system/lib/pthread/thread_mailbox.c

@@ -71,7 +71,6 @@ void _emscripten_thread_mailbox_init(pthread_t thread) {
 }
 
 // Exported for use in worker.js, but otherwise an internal function.
-EMSCRIPTEN_KEEPALIVE
 void _emscripten_check_mailbox() {
   // Before we attempt to execute a request from another thread make sure we
   // are in sync with all the loaded code.

test/code_size/embind_val_wasm.json

@@ -3,8 +3,8 @@
   "a.html.gz": 431,
   "a.js": 7498,
   "a.js.gz": 3142,
-  "a.wasm": 9669,
-  "a.wasm.gz": 4962,
-  "total": 17840,
-  "total_gz": 8535
+  "a.wasm": 9628,
+  "a.wasm.gz": 4938,
+  "total": 17799,
+  "total_gz": 8511
 }

test/other/metadce/test_metadce_minimal_pthreads.jssize

@@ -1 +1 @@
-14110
+14052