[Wasm] Revert swift_once body workarounds in SILGen

Author: kateinoigakukun

lib/SILGen/SILGen.cpp

@@ -1651,19 +1651,7 @@ SILFunction *SILGenModule::emitLazyGlobalInitializer(StringRef funcName,
       cast<FuncDecl>(getBuiltinValueDecl(C, C.getIdentifier("once")));
   auto blockParam = onceBuiltin->getParameters()->get(1);
   auto *type = blockParam->getType()->castTo<FunctionType>();
-  SmallVector<AnyFunctionType::Param, 1> params;
-  // wasm: Lazy global init is used with swift_once which passes a context
-  // pointer parameter. If lazy global init doesn't take a context argument,
-  // caller and callee signatures are mismatched and it causes runtime
-  // exception on WebAssembly runtime. So we need to add dummy argument
-  // to consume the context pointer.
-  // See also: emitLazyGlobalInitializer
-  if (C.LangOpts.Target.isOSBinFormatWasm()) {
-    auto dummyParam = AnyFunctionType::Param(C.getUnsafeRawPointerDecl()->getDeclaredInterfaceType()
-                                             ->getCanonicalType());
-    params.push_back(dummyParam);
-  }
-  Type initType = FunctionType::get(params, TupleType::getEmpty(C),
+  Type initType = FunctionType::get({}, TupleType::getEmpty(C),
                                     type->getExtInfo());
   auto initSILType = cast<SILFunctionType>(
       Types.getLoweredRValueType(TypeExpansionContext::minimal(), initType));

lib/SILGen/SILGenGlobalVariable.cpp

@@ -228,19 +228,6 @@ void SILGenFunction::emitLazyGlobalInitializer(PatternBindingDecl *binding,
                                                unsigned pbdEntry) {
   MagicFunctionName = SILGenModule::getMagicFunctionName(binding->getDeclContext());
 
-  ASTContext &C = getASTContext();
-  // wasm: Lazy global init is used with swift_once which passes a context
-  // pointer parameter. If lazy global init doesn't take a context argument,
-  // caller and callee signatures are mismatched and it causes runtime
-  // exception on WebAssembly runtime. So we need to add dummy argument
-  // to consume the context pointer.
-  // See also: emitLazyGlobalInitializer
-  if (C.LangOpts.Target.isOSBinFormatWasm()) {
-    auto UnsafeRawPointer = C.getUnsafeRawPointerDecl();
-    auto UnsafeRawPtrTy = getLoweredType(UnsafeRawPointer->getDeclaredInterfaceType());
-    F.front().createFunctionArgument(UnsafeRawPtrTy);
-  }
-
   {
     Scope scope(Cleanups, binding);