Avoid separate emval_call_void_method (#20368)

Author: RReverser

src/embind/emval.js

@@ -13,7 +13,7 @@
 
 // -- jshint doesn't understand library syntax, so we need to mark the symbols exposed here
 /*global getStringOrSymbol, emval_handles, Emval, __emval_unregister, count_emval_handles, emval_symbols, __emval_decref, emval_newers*/
-/*global craftEmvalAllocator, emval_addMethodCaller, emval_methodCallers, addToLibrary, emval_allocateDestructors, global, emval_lookupTypes, makeLegalFunctionName*/
+/*global craftEmvalAllocator, emval_addMethodCaller, emval_methodCallers, addToLibrary, global, emval_lookupTypes, makeLegalFunctionName*/
 /*global emval_get_global*/
 
 var LibraryEmVal = {
@@ -370,13 +370,6 @@ var LibraryEmVal = {
     return a;
   },
 
-  $emval_allocateDestructors__deps: ['$Emval'],
-  $emval_allocateDestructors: (destructorsRef) => {
-    var destructors = [];
-    {{{ makeSetValue('destructorsRef', '0', 'Emval.toHandle(destructors)', '*') }}};
-    return destructors;
-  },
-
   // Leave id 0 undefined.  It's not a big deal, but might be confusing
   // to have null be a valid method caller.
   $emval_methodCallers: [undefined],
@@ -414,9 +407,7 @@ var LibraryEmVal = {
           types[i].deleteObject(argN[i]);
         }
       }
-      if (!retType.isVoid) {
-        return retType['toWireType'](destructors, rv);
-      }
+      return retType['toWireType'](destructors, rv);
     };
 #else
     var params = ["retType"];
@@ -461,20 +452,18 @@ var LibraryEmVal = {
     return emval_addMethodCaller(invokerFunction);
   },
 
-  _emval_call_method__deps: ['$emval_allocateDestructors', '$getStringOrSymbol', '$emval_methodCallers', '$Emval'],
+  _emval_call_method__deps: ['$getStringOrSymbol', '$emval_methodCallers', '$Emval'],
   _emval_call_method: (caller, handle, methodName, destructorsRef, args) => {
     caller = emval_methodCallers[caller];
     handle = Emval.toValue(handle);
     methodName = getStringOrSymbol(methodName);
-    return caller(handle, methodName, emval_allocateDestructors(destructorsRef), args);
-  },
-
-  _emval_call_void_method__deps: ['$emval_allocateDestructors', '$getStringOrSymbol', '$emval_methodCallers', '$Emval'],
-  _emval_call_void_method: (caller, handle, methodName, args) => {
-    caller = emval_methodCallers[caller];
-    handle = Emval.toValue(handle);
-    methodName = getStringOrSymbol(methodName);
-    caller(handle, methodName, null, args);
+    var destructors = [];
+    var result = caller(handle, methodName, destructors, args);
+    // void and any other types w/o destructors don't need to allocate a handle
+    if (destructors.length) {
+      {{{ makeSetValue('destructorsRef', '0', 'Emval.toHandle(destructors)', '*') }}};
+    }
+    return result;
   },
 
   _emval_typeof__deps: ['$Emval'],

src/library_sigs.js

@@ -339,7 +339,6 @@ sigs = {
   _emval_await__sig: 'pp',
   _emval_call__sig: 'ppipp',
   _emval_call_method__sig: 'dppppp',
-  _emval_call_void_method__sig: 'vpppp',
   _emval_decref__sig: 'vp',
   _emval_delete__sig: 'ipp',
   _emval_equals__sig: 'ipp',

system/include/emscripten/val.h

@@ -99,11 +99,6 @@ EM_GENERIC_WIRE_TYPE _emval_call_method(
     const char* methodName,
     EM_DESTRUCTORS* destructors,
     EM_VAR_ARGS argv);
-void _emval_call_void_method(
-    EM_METHOD_CALLER caller,
-    EM_VAL handle,
-    const char* methodName,
-    EM_VAR_ARGS argv);
 EM_VAL _emval_typeof(EM_VAL value);
 bool _emval_instanceof(EM_VAL object, EM_VAL constructor);
 bool _emval_is_number(EM_VAL object);
@@ -145,7 +140,9 @@ struct DestructorsRunner {
       : destructors(d)
   {}
   ~DestructorsRunner() {
-    _emval_run_destructors(destructors);
+    if (destructors) {
+      _emval_run_destructors(destructors);
+    }
   }
 
   DestructorsRunner(const DestructorsRunner&) = delete;
@@ -170,12 +167,17 @@ struct GenericWireTypeConverter<Pointee*> {
 };
 
 template<typename T>
-T fromGenericWireType(double g) {
+T fromGenericWireType(EM_GENERIC_WIRE_TYPE g) {
   typedef typename BindingType<T>::WireType WireType;
   WireType wt = GenericWireTypeConverter<WireType>::from(g);
   return BindingType<T>::fromWireType(wt);
 }
 
+template<>
+inline void fromGenericWireType<void>(EM_GENERIC_WIRE_TYPE g) {
+  (void)g;
+}
+
 template<typename... Args>
 struct PackSize;
 
@@ -271,7 +273,7 @@ struct MethodCaller {
     auto caller = Signature<ReturnType, Args...>::get_method_caller();
 
     WireTypePack<Args...> argv(std::forward<Args>(args)...);
-    EM_DESTRUCTORS destructors;
+    EM_DESTRUCTORS destructors = nullptr;
     EM_GENERIC_WIRE_TYPE result = _emval_call_method(
       caller,
       handle,
@@ -283,20 +285,6 @@ struct MethodCaller {
   }
 };
 
-template<typename... Args>
-struct MethodCaller<void, Args...> {
-  static void call(EM_VAL handle, const char* methodName, Args&&... args) {
-    auto caller = Signature<void, Args...>::get_method_caller();
-
-    WireTypePack<Args...> argv(std::forward<Args>(args)...);
-    _emval_call_void_method(
-      caller,
-      handle,
-      methodName,
-      argv);
-  }
-};
-
 } // end namespace internal
 
 #define EMSCRIPTEN_SYMBOL(name)                                         \