Minor TLS init refactoring. NFC (#17002)

Preparing for #16948

Author: sbc100

emcc.py

@@ -1514,7 +1514,7 @@ def setup_pthreads(target):
     '__emscripten_thread_init',
     '__emscripten_thread_exit',
     '__emscripten_thread_crashed',
-    '_emscripten_tls_init',
+    '__emscripten_tls_init',
     '_pthread_self',
     'executeNotifiedProxyingQueue',
   ]
@@ -1858,7 +1858,7 @@ def phase_linker_setup(options, state, newargs, user_settings):
 
   if settings.USE_PTHREADS:
     settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE += [
-        '$registerTlsInit',
+        '$registerTLSInit',
     ]
 
   if settings.RELOCATABLE:

src/library_dylink.js

@@ -72,7 +72,7 @@ var LibraryDylink = {
       '__tls_size',
       '__tls_align',
       '__set_stack_limits',
-      'emscripten_tls_init',
+      '_emscripten_tls_init',
       '__wasm_init_tls',
       '__wasm_call_ctors',
     ].includes(symName)
@@ -593,8 +593,8 @@ var LibraryDylink = {
         // initialize the module
 #if USE_PTHREADS
         // Only one thread (currently The main thread) should call
-        // __wasm_call_ctors, but all threads need to call emscripten_tls_init
-        registerTlsInit(moduleExports['emscripten_tls_init'], instance.exports, metadata)
+        // __wasm_call_ctors, but all threads need to call _emscripten_tls_init
+        registerTLSInit(moduleExports['_emscripten_tls_init'], instance.exports, metadata)
         if (!ENVIRONMENT_IS_PTHREAD) {
 #endif
           var init = moduleExports['__wasm_call_ctors'];

src/library_pthread.js

@@ -94,7 +94,7 @@ var LibraryPThread = {
       // worker.js is not compiled together with us, and must access certain
       // things.
       PThread['receiveObjectTransfer'] = PThread.receiveObjectTransfer;
-      PThread['threadInit'] = PThread.threadInit;
+      PThread['threadInitTLS'] = PThread.threadInitTLS;
 #if !MINIMAL_RUNTIME
       PThread['setExitStatus'] = PThread.setExitStatus;
 #endif
@@ -212,11 +212,11 @@ var LibraryPThread = {
 #endif
     },
     // Called by worker.js each time a thread is started.
-    threadInit: function() {
+    threadInitTLS: function() {
 #if PTHREADS_DEBUG
-      err('threadInit.');
+      err('threadInitTLS.');
 #endif
-      // Call thread init functions (these are the emscripten_tls_init for each
+      // Call thread init functions (these are the _emscripten_tls_init for each
       // module loaded.
       for (var i in PThread.tlsInitFunctions) {
         if (PThread.tlsInitFunctions.hasOwnProperty(i)) PThread.tlsInitFunctions[i]();
@@ -475,12 +475,12 @@ var LibraryPThread = {
   },
 
 #if MAIN_MODULE
-  $registerTlsInit: function(tlsInitFunc, moduleExports, metadata) {
+  $registerTLSInit: function(tlsInitFunc, moduleExports, metadata) {
 #if DYLINK_DEBUG
-    err("registerTlsInit: " + tlsInitFunc);
+    err("registerTLSInit: " + tlsInitFunc);
 #endif
     // In relocatable builds, we use the result of calling tlsInitFunc
-    // (`emscripten_tls_init`) to relocate the TLS exports of the module
+    // (`_emscripten_tls_init`) to relocate the TLS exports of the module
     // according to this new __tls_base.
     function tlsInitWrapper() {
       var __tls_base = tlsInitFunc();
@@ -512,7 +512,7 @@ var LibraryPThread = {
     }
   },
 #else
-  $registerTlsInit: function(tlsInitFunc) {
+  $registerTLSInit: function(tlsInitFunc) {
     PThread.tlsInitFunctions.push(tlsInitFunc);
   },
 #endif
@@ -599,7 +599,7 @@ var LibraryPThread = {
       /*start_profiling=*/true
 #endif
     );
-    PThread.threadInit();
+    PThread.threadInitTLS();
   },
 
   $pthreadCreateProxied__internal: true,

src/postamble_minimal.js

@@ -85,7 +85,7 @@ function initRuntime(asm) {
 #endif
 
 #if USE_PTHREADS
-  PThread.tlsInitFunctions.push(asm['emscripten_tls_init']);
+  PThread.tlsInitFunctions.push(asm['_emscripten_tls_init']);
 #endif
 
 #if hasExportedFunction('___wasm_call_ctors')

src/preamble.js

@@ -1022,9 +1022,9 @@ function createWasm() {
 
 #if USE_PTHREADS
 #if MAIN_MODULE
-    registerTlsInit(Module['asm']['emscripten_tls_init'], instance.exports, metadata);
+    registerTLSInit(Module['asm']['_emscripten_tls_init'], instance.exports, metadata);
 #else
-    registerTlsInit(Module['asm']['emscripten_tls_init']);
+    registerTLSInit(Module['asm']['_emscripten_tls_init']);
 #endif
 #endif
 

src/worker.js

@@ -211,7 +211,7 @@ self.onmessage = (e) => {
       // Also call inside JS module to set up the stack frame for this pthread in JS module scope
       Module['establishStackSpace']();
       Module['PThread'].receiveObjectTransfer(e.data);
-      Module['PThread'].threadInit();
+      Module['PThread'].threadInitTLS();
 
       if (!initializedJS) {
 #if EMBIND

system/lib/libc/musl/src/thread/pthread_join.c

@@ -7,10 +7,6 @@ static void dummy1(pthread_t t)
 }
 weak_alias(dummy1, __tl_sync);
 
-#ifdef __EMSCRIPTEN__ // XXX Emscripten add extern for __emscripten_thread_cleanup
-extern void __emscripten_thread_cleanup(pthread_t thread);
-#endif
-
 static int __pthread_timedjoin_np(pthread_t t, void **res, const struct timespec *at)
 {
 #ifdef __EMSCRIPTEN__

system/lib/pthread/emscripten_thread_state.S

@@ -4,8 +4,6 @@
 #define PTR i32
 #endif
 
-.globaltype __tls_base, PTR
-
 .globaltype thread_ptr, PTR
 thread_ptr:
 
@@ -37,14 +35,6 @@ __set_thread_state:
   global.set supports_wait
   end_function
 
-# Accessor for `__tls_base` symbol which is a wasm global an not directly
-# accessible from C/C++.
-.globl _emscripten_tls_base
-_emscripten_tls_base:
-  .functype _emscripten_tls_base () -> (PTR)
-  global.get __tls_base
-  end_function
-
 # Semantically the same as testing "!ENVIRONMENT_IS_PTHREAD" in JS
 .globl emscripten_is_main_runtime_thread
 emscripten_is_main_runtime_thread:

system/lib/pthread/emscripten_tls_init.c

@@ -46,7 +46,7 @@ static int is_non_primary(void) {
   return val;
 }
 
-void emscripten_tls_free() {
+void _emscripten_tls_free() {
   void* tls_block = __builtin_wasm_tls_base();
   if (tls_block && is_non_primary()) {
 #ifdef DEBUG_TLS
@@ -56,7 +56,7 @@ void emscripten_tls_free() {
   }
 }
 
-void* emscripten_tls_init(void) {
+void* _emscripten_tls_init(void) {
   size_t tls_size = __builtin_wasm_tls_size();
   void* tls_block = __builtin_wasm_tls_base();
   if (is_non_primary() || (!tls_block && tls_size)) {

system/lib/pthread/pthread_create.c

@@ -22,10 +22,10 @@
 
 // See musl's pthread_create.c
 
-extern int __pthread_create_js(struct pthread *thread, const pthread_attr_t *attr, void *(*start_routine) (void *), void *arg);
-extern void __set_thread_state(pthread_t ptr, int is_main, int is_runtime, int can_block);
-extern int _emscripten_default_pthread_stack_size();
-extern void __emscripten_thread_cleanup(pthread_t thread);
+int __pthread_create_js(struct pthread *thread, const pthread_attr_t *attr, void *(*start_routine) (void *), void *arg);
+int _emscripten_default_pthread_stack_size();
+void __set_thread_state(pthread_t ptr, int is_main, int is_runtime, int can_block);
+
 extern int8_t __dso_handle;
 
 static void dummy_0()
@@ -196,8 +196,6 @@ void _emscripten_thread_free_data(pthread_t t) {
   emscripten_builtin_free(t);
 }
 
-void emscripten_tls_free(void);
-
 void _emscripten_thread_exit(void* result) {
   struct pthread *self = __pthread_self();
   assert(self);
@@ -212,7 +210,7 @@ void _emscripten_thread_exit(void* result) {
   // Call into the musl function that runs destructors of all thread-specific data.
   __pthread_tsd_run_dtors();
 
-  emscripten_tls_free();
+  _emscripten_tls_free();
 
   if (!--libc.threads_minus_1) libc.need_locks = 0;