Move emscripten_proxy_main.c to crt1_proxy_main.c. NFC (#17195)

This really is the crt1.o for applications built with PROXY_TO_PTHREAD.

Author: sbc100

embuilder.py

@@ -56,6 +56,7 @@
     'struct_info',
     'libstandalonewasm',
     'crt1',
+    'crt1_proxy_main',
     'libunwind-except',
     'libnoexit',
 ]

emcc.py

@@ -1547,9 +1547,6 @@ def setup_pthreads(target):
   if settings.MINIMAL_RUNTIME:
     building.user_requested_exports.add('exit')
 
-  if settings.PROXY_TO_PTHREAD:
-    settings.REQUIRED_EXPORTS += ['emscripten_proxy_main']
-
   # All proxying async backends will need this.
   if settings.WASMFS:
     settings.REQUIRED_EXPORTS += ['emscripten_proxy_finish']
@@ -1744,8 +1741,7 @@ def phase_linker_setup(options, state, newargs, user_settings):
         settings.EXPECT_MAIN = 0
     else:
       assert not settings.EXPORTED_FUNCTIONS
-      # With PROXY_TO_PTHREAD we don't export `main` at all but instead
-      # we export `emscripten_proxy_main` (elsewhwere).
+      # With PROXY_TO_PTHREAD we don't export `main` at all but instead `_emscripten_proxy_main`.
       if not settings.PROXY_TO_PTHREAD:
         settings.EXPORTED_FUNCTIONS = ['_main']
 

src/postamble.js

@@ -131,7 +131,7 @@ function callMain(args) {
 #if PROXY_TO_PTHREAD
   // User requested the PROXY_TO_PTHREAD option, so call a stub main which pthread_create()s a new thread
   // that will call the user's real main() for the application.
-  var entryFunction = Module['_emscripten_proxy_main'];
+  var entryFunction = Module['__emscripten_proxy_main'];
 #else
   var entryFunction = Module['_main'];
 #endif

src/postamble_minimal.js

@@ -19,7 +19,7 @@ function run() {
   // User requested the PROXY_TO_PTHREAD option, so call a stub main which
   // pthread_create()s a new thread that will call the user's real main() for
   // the application.
-  var ret = _emscripten_proxy_main();
+  var ret = __emscripten_proxy_main();
 #else
   var ret = _main();
 

system/lib/pthread/emscripten_proxy_main.c renamed to system/lib/libc/crt1_proxy_main.c

@@ -33,7 +33,7 @@ static void* _main_thread(void* param) {
   return NULL;
 }
 
-int emscripten_proxy_main(int argc, char** argv) {
+EMSCRIPTEN_KEEPALIVE int _emscripten_proxy_main(int argc, char** argv) {
   pthread_attr_t attr;
   pthread_attr_init(&attr);
   pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);

tests/other/metadce/test_metadce_minimal_pthreads.funcs

@@ -10,13 +10,14 @@ $__pthread_setcancelstate
 $__set_thread_state
 $__stdio_write
 $__timedwait
-$__wake.2
+$__wake
 $__wasi_syscall_ret
 $__wasm_call_ctors
 $__wasm_init_memory
 $__wasm_init_tls
 $_do_call
 $_emscripten_proxy_execute_task_queue
+$_emscripten_proxy_main
 $_emscripten_thread_crashed
 $_emscripten_thread_exit
 $_emscripten_thread_free_data
@@ -27,7 +28,7 @@ $_main_thread
 $a_cas
 $a_cas_p.1
 $a_dec
-$a_fetch_add.1
+$a_fetch_add
 $a_inc
 $a_swap
 $add
@@ -37,17 +38,16 @@ $dlmalloc
 $do_dispatch_to_thread
 $em_queued_call_malloc
 $emscripten_async_run_in_main_thread
+$emscripten_current_thread_process_queued_calls
 $emscripten_futex_wait
 $emscripten_futex_wake
-$emscripten_proxy_execute_queue
-$emscripten_proxy_main
 $emscripten_run_in_main_runtime_thread_js
 $emscripten_stack_set_limits
 $get_tasks_for_thread
 $init_file_lock
 $init_mparams
 $memset
-$pthread_mutexattr_destroy
+$pthread_attr_destroy
 $sbrk
 $stackAlloc
 $stackRestore

tests/other/metadce/test_metadce_minimal_pthreads.jssize

@@ -1 +1 @@
-16048
+16051

tests/other/metadce/test_metadce_minimal_pthreads.size

@@ -1 +1 @@
-18318
+18289

tools/building.py

@@ -336,11 +336,14 @@ def lld_flags_for_executable(external_symbols):
       if not settings.EXPECT_MAIN:
         cmd += ['--entry=_initialize']
     else:
-      # TODO(sbc): Avoid passing --no-entry when we know we have an entry point.
-      # For now we need to do this sice the entry point can be either `main` or
-      # `__main_argv_argc`, but we should address that by using a single `_start`
-      # function like we do in STANDALONE_WASM mode.
-      cmd += ['--no-entry']
+      if settings.PROXY_TO_PTHREAD:
+        cmd += ['--entry=_emscripten_proxy_main']
+      else:
+        # TODO(sbc): Avoid passing --no-entry when we know we have an entry point.
+        # For now we need to do this sice the entry point can be either `main` or
+        # `__main_argv_argc`, but we should address that by using a single `_start`
+        # function like we do in STANDALONE_WASM mode.
+        cmd += ['--no-entry']
     if not settings.ALLOW_MEMORY_GROWTH:
       cmd.append('--max-memory=%d' % settings.INITIAL_MEMORY)
     elif settings.MAXIMUM_MEMORY != -1:

tools/system_libs.py

@@ -834,7 +834,6 @@ def get_files(self):
           'proxying.c',
           'pthread_create.c',
           'pthread_kill.c',
-          'emscripten_proxy_main.c',
           'emscripten_thread_init.c',
           'emscripten_thread_state.S',
           'emscripten_futex_wait.c',
@@ -1170,6 +1169,20 @@ def can_use(self):
     return super().can_use() and settings.STANDALONE_WASM
 
 
+class crt1_proxy_main(MuslInternalLibrary):
+  name = 'crt1_proxy_main'
+  src_dir = 'system/lib/libc'
+  src_files = ['crt1_proxy_main.c']
+
+  force_object_files = True
+
+  def get_ext(self):
+    return '.o'
+
+  def can_use(self):
+    return super().can_use() and settings.PROXY_TO_PTHREAD
+
+
 class crtbegin(MuslInternalLibrary):
   name = 'crtbegin'
   cflags = ['-sUSE_PTHREADS']
@@ -1825,11 +1838,14 @@ def add_library(libname):
     if settings.SHARED_MEMORY:
       add_library('crtbegin')
 
-    if settings.STANDALONE_WASM:
-      if settings.EXPECT_MAIN:
-        add_library('crt1')
-      else:
-        add_library('crt1_reactor')
+    if not settings.SIDE_MODULE:
+      if settings.STANDALONE_WASM:
+        if settings.EXPECT_MAIN:
+          add_library('crt1')
+        else:
+          add_library('crt1_reactor')
+      elif settings.PROXY_TO_PTHREAD:
+        add_library('crt1_proxy_main')
 
   if settings.SIDE_MODULE:
     return libs_to_link