[Wasm64] Enable emescipten exceptions and SjLj (#19262)

Whatever was preventing this from working previously must have been
fixed by all the work we have done in the mean time on wasm64 support
more generally.

Author: sbc100

emcc.py

@@ -2424,8 +2424,6 @@ def phase_linker_setup(options, state, newargs):
   if settings.MEMORY64:
     if settings.ASYNCIFY and settings.MEMORY64 == 1:
       exit_with_error('MEMORY64=1 is not compatible with ASYNCIFY')
-    if not settings.DISABLE_EXCEPTION_CATCHING:
-      exit_with_error('MEMORY64 is not compatible with DISABLE_EXCEPTION_CATCHING=0')
     # Any "pointers" passed to JS will now be i64's, in both modes.
     settings.WASM_BIGINT = 1
 

emscripten.py

@@ -886,6 +886,8 @@ def create_wasm64_wrappers(metadata):
     'emscripten_stack_set_limits': '_pp',
     '__set_stack_limits': '_pp',
     '__cxa_can_catch': '_ppp',
+    '__cxa_increment_exception_refcount': '_p',
+    '__cxa_decrement_exception_refcount': '_p',
     '_wasmfs_write_file': '_ppp',
     '__dl_seterr': '_pp',
     '_emscripten_run_in_main_runtime_thread_js': '___p_',

src/library_exceptions.js

@@ -213,6 +213,7 @@ var LibraryExceptions = {
   },
 
   __cxa_current_primary_exception__deps: ['$exceptionCaught', '__cxa_increment_exception_refcount'],
+  __cxa_current_primary_exception__sig: 'p',
   __cxa_current_primary_exception: function() {
     if (!exceptionCaught.length) {
       return 0;
@@ -223,6 +224,7 @@ var LibraryExceptions = {
   },
 
   __cxa_rethrow_primary_exception__deps: ['$ExceptionInfo', '$exceptionCaught', '__cxa_rethrow'],
+  __cxa_rethrow_primary_exception__sig: 'vp',
   __cxa_rethrow_primary_exception: function(ptr) {
     if (!ptr) return;
     var info = new ExceptionInfo(ptr);
@@ -242,7 +244,11 @@ var LibraryExceptions = {
   // We'll do that here, instead, to keep things simpler.
   __cxa_find_matching_catch__deps: ['$exceptionLast', '$ExceptionInfo', '__resumeException', '__cxa_can_catch', 'setTempRet0'],
   __cxa_find_matching_catch: function() {
-    var thrown = 
+    // Here we use explicit calls to `from64`/`to64` rather then using the
+    // `__sig` attribute to perform these automatically.  This is because the
+    // `__sig` wrapper uses arrow function notation, which is not compatible
+    // with the use of `arguments` in this function.
+    var thrown =
 #if EXCEPTION_STACK_TRACES
       exceptionLast && exceptionLast.excPtr;
 #else
@@ -251,15 +257,15 @@ var LibraryExceptions = {
     if (!thrown) {
       // just pass through the null ptr
       setTempRet0(0);
-      return 0;
+      return {{{ to64(0) }}};
     }
     var info = new ExceptionInfo(thrown);
     info.set_adjusted_ptr(thrown);
     var thrownType = info.get_type();
     if (!thrownType) {
       // just pass through the thrown ptr
       setTempRet0(0);
-      return thrown;
+      return {{{ to64('thrown') }}};
     }
 
     // can_catch receives a **, add indirection
@@ -272,6 +278,8 @@ var LibraryExceptions = {
     // return the type of the catch block which should be called.
     for (var i = 0; i < arguments.length; i++) {
       var caughtType = arguments[i];
+      {{{ from64('caughtType') }}};
+
       if (caughtType === 0 || caughtType === thrownType) {
         // Catch all clause matched or exactly the same type is caught
         break;
@@ -282,11 +290,11 @@ var LibraryExceptions = {
         dbg("  __cxa_find_matching_catch found " + [ptrToString(info.get_adjusted_ptr()), caughtType]);
 #endif
         setTempRet0(caughtType);
-        return thrown;
+        return {{{ to64('thrown') }}};
       }
     }
     setTempRet0(thrownType);
-    return thrown;
+    return {{{ to64('thrown') }}};
   },
 
   __resumeException__deps: ['$exceptionLast'],

test/test_core.py

@@ -109,8 +109,6 @@ def metafunc(self, is_native):
       self.set_setting('SUPPORT_LONGJMP', 'wasm')
       f(self)
     else:
-      if self.get_setting('MEMORY64'):
-        self.skipTest('MEMORY64 does not yet support emscripten EH/SjLj')
       self.set_setting('DISABLE_EXCEPTION_CATCHING', 0)
       self.set_setting('SUPPORT_LONGJMP', 'emscripten')
       # DISABLE_EXCEPTION_CATCHING=0 exports __cxa_can_catch and
@@ -549,7 +547,6 @@ def test_i64_varargs(self):
     self.do_core_test('test_i64_varargs.c', args='waka fleefl asdfasdfasdfasdf'.split())
 
   @no_wasm2js('wasm_bigint')
-  @no_wasm64('MEMORY64 does not yet support exceptions')
   @requires_node
   def test_i64_invoke_bigint(self):
     self.set_setting('WASM_BIGINT')
@@ -1100,7 +1097,6 @@ def test_longjmp_standalone(self):
   def test_longjmp(self):
     self.do_core_test('test_longjmp.c')
 
-  @no_wasm64('MEMORY64 does not yet support SJLJ')
   def test_longjmp_with_and_without_exceptions(self):
     # Emscripten SjLj with and without Emscripten EH support
     self.set_setting('SUPPORT_LONGJMP', 'emscripten')
@@ -1157,7 +1153,6 @@ def test_longjmp_stacked(self):
   def test_longjmp_exc(self):
     self.do_core_test('test_longjmp_exc.c', assert_returncode=NON_ZERO)
 
-  @no_wasm64('MEMORY64 does not yet support exception handling')
   def test_longjmp_throw(self):
     for disable_throw in [0, 1]:
       print(disable_throw)
@@ -1237,7 +1232,6 @@ def test_exceptions(self):
     self.maybe_closure()
     self.do_run_from_file(test_file('core/test_exceptions.cpp'), test_file('core/test_exceptions_caught.out'))
 
-  @no_wasm64('MEMORY64 does not yet support exceptions')
   def test_exceptions_with_and_without_longjmp(self):
     self.set_setting('EXCEPTION_DEBUG')
     self.maybe_closure()
@@ -1267,7 +1261,6 @@ def test_exceptions_off(self):
 
   @no_wasmfs('https://github.com/emscripten-core/emscripten/issues/16816')
   @no_asan('TODO: ASan support in minimal runtime')
-  @no_wasm64('MEMORY64 does not yet support exceptions')
   def test_exceptions_minimal_runtime(self):
     self.set_setting('EXIT_RUNTIME')
     self.maybe_closure()
@@ -1373,7 +1366,6 @@ def test_exceptions_3(self):
     print('2')
     self.do_run('src.js', 'Caught exception: Hello\nDone.', args=['2'], no_build=True)
 
-  @no_wasm64('MEMORY64 does not yet support exceptions')
   def test_exceptions_allowed(self):
     self.set_setting('EXCEPTION_CATCHING_ALLOWED', ["_Z12somefunctionv"])
     # otherwise it is inlined and not identified
@@ -1425,7 +1417,6 @@ def test_exceptions_allowed(self):
     if not any(o in self.emcc_args for o in ('-O3', '-Oz', '-Os')):
       self.assertLess(disabled_size, fake_size)
 
-  @no_wasm64('MEMORY64 does not yet support exceptions')
   def test_exceptions_allowed_2(self):
     self.set_setting('EXCEPTION_CATCHING_ALLOWED', ["main"])
     # otherwise it is inlined and not identified
@@ -1437,7 +1428,6 @@ def test_exceptions_allowed_2(self):
     self.emcc_args += ['-DMAIN_NO_SIGNATURE']
     self.do_core_test('test_exceptions_allowed_2.cpp')
 
-  @no_wasm64('MEMORY64 does not yet support exceptions')
   def test_exceptions_allowed_uncaught(self):
     self.emcc_args += ['-std=c++11']
     self.set_setting('EXCEPTION_CATCHING_ALLOWED', ["_Z4testv"])
@@ -1446,7 +1436,6 @@ def test_exceptions_allowed_uncaught(self):
 
     self.do_core_test('test_exceptions_allowed_uncaught.cpp')
 
-  @no_wasm64('MEMORY64 does not yet support exceptions')
   def test_exceptions_allowed_misuse(self):
     self.set_setting('EXCEPTION_CATCHING_ALLOWED', ['foo'])
 
@@ -1608,7 +1597,6 @@ def test_exceptions_rethrow_missing(self):
     create_file('main.cpp', 'int main() { throw; }')
     self.do_runf('main.cpp', None, assert_returncode=NON_ZERO)
 
-  @no_wasm64('MEMORY64 does not yet support exceptions')
   @with_both_eh_sjlj
   def test_EXPORT_EXCEPTION_HANDLING_HELPERS(self):
     self.set_setting('ASSERTIONS', 0)
@@ -2471,7 +2459,6 @@ def test_memorygrowth_3_force_fail_reallocBuffer(self):
   })
   @no_asan('requires more memory when growing')
   @no_lsan('requires more memory when growing')
-  @no_wasm64('does not fail under wasm64')
   def test_aborting_new(self, args):
     # test that C++ new properly errors if we fail to malloc when growth is
     # enabled, with or without growth
@@ -4636,7 +4623,6 @@ def test_dylink_i64_c(self):
 
   @needs_dylink
   @also_with_wasm_bigint
-  @no_wasm64('MEMORY64 does not yet support exceptions')
   def test_dylink_i64_invoke(self):
     self.set_setting('DISABLE_EXCEPTION_CATCHING', 0)
     self.dylink_test(r'''\
@@ -9350,7 +9336,6 @@ def test_pthread_create_embind_stack_check(self):
     self.do_run_in_out_file_test('core/pthread/create.cpp')
 
   @node_pthreads
-  @no_wasm64('MEMORY64 does not yet support exceptions')
   def test_pthread_exceptions(self):
     self.set_setting('PTHREAD_POOL_SIZE', 2)
     self.set_setting('EXIT_RUNTIME')
@@ -9469,7 +9454,6 @@ def test_pthread_dylink_entry_point(self, args):
 
   @needs_dylink
   @node_pthreads
-  @no_wasm64('MEMORY64 does not yet support exceptions')
   def test_pthread_dylink_exceptions(self):
     self.emcc_args += ['-Wno-experimental', '-pthread']
     self.emcc_args.append('-fexceptions')