[wasm] Remove obsolete {GetWasmFunctionForExport} helper.

R=titzer@chromium.org

Change-Id: I2de3bef1753669c7a9f653ece14f168930392180
Reviewed-on: https://chromium-review.googlesource.com/997692Reviewed-by: Ben Titzer <titzer@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52394}

src/wasm/wasm-js.cc

@@ -854,11 +854,8 @@ void WebAssemblyTableSet(const v8::FunctionCallbackInfo<v8::Value>& args) {
 
   // Parameter 1.
   i::Handle<i::Object> value = Utils::OpenHandle(*args[1]);
-  // TODO(titzer): use WasmExportedFunction::IsWasmExportedFunction() here.
   if (!value->IsNull(i_isolate) &&
-      (!value->IsJSFunction() ||
-       i::Handle<i::JSFunction>::cast(value)->code()->kind() !=
-           i::Code::JS_TO_WASM_FUNCTION)) {
+      !i::WasmExportedFunction::IsWasmExportedFunction(*value)) {
     thrower.TypeError("Argument 1 must be null or a WebAssembly function");
     return;
   }

src/wasm/wasm-module.cc

@@ -138,20 +138,6 @@ std::ostream& operator<<(std::ostream& os, const WasmFunctionName& name) {
 WasmModule::WasmModule(std::unique_ptr<Zone> owned)
     : signature_zone(std::move(owned)) {}
 
-WasmFunction* GetWasmFunctionForExport(Isolate* isolate,
-                                       Handle<Object> target) {
-  if (target->IsJSFunction()) {
-    Handle<JSFunction> func = Handle<JSFunction>::cast(target);
-    if (func->code()->kind() == Code::JS_TO_WASM_FUNCTION) {
-      auto exported = Handle<WasmExportedFunction>::cast(func);
-      Handle<WasmInstanceObject> other_instance(exported->instance(), isolate);
-      int func_index = exported->function_index();
-      return &other_instance->module()->functions[func_index];
-    }
-  }
-  return nullptr;
-}
-
 bool IsWasmCodegenAllowed(Isolate* isolate, Handle<Context> context) {
   // TODO(wasm): Once wasm has its own CSP policy, we should introduce a
   // separate callback that includes information about the module about to be

src/wasm/wasm-module.h

@@ -262,13 +262,6 @@ V8_EXPORT_PRIVATE Handle<JSArray> GetCustomSections(
 // function index, the inner one by the local index.
 Handle<FixedArray> DecodeLocalNames(Isolate*, Handle<WasmSharedModuleData>);
 
-// If the target is an export wrapper, return the {WasmFunction*} corresponding
-// to the wrapped wasm function; in all other cases, return nullptr.
-// The returned pointer is owned by the wasm instance target belongs to. The
-// result is alive as long as the instance exists.
-// TODO(titzer): move this to WasmExportedFunction.
-WasmFunction* GetWasmFunctionForExport(Isolate* isolate, Handle<Object> target);
-
 void UnpackAndRegisterProtectedInstructions(
     Isolate* isolate, const wasm::NativeModule* native_module);
 

src/wasm/wasm-objects.cc

@@ -285,8 +285,11 @@ void WasmTableObject::Set(Isolate* isolate, Handle<WasmTableObject> table,
   }
 
   // TODO(titzer): Change this to MaybeHandle<WasmExportedFunction>
+  DCHECK(WasmExportedFunction::IsWasmExportedFunction(*function));
   auto exported_function = Handle<WasmExportedFunction>::cast(function);
-  auto* wasm_function = wasm::GetWasmFunctionForExport(isolate, function);
+  Handle<WasmInstanceObject> other_instance(exported_function->instance());
+  int func_index = exported_function->function_index();
+  auto* wasm_function = &other_instance->module()->functions[func_index];
   DCHECK_NOT_NULL(wasm_function);
   DCHECK_NOT_NULL(wasm_function->sig);
   wasm::WasmCode* wasm_code = exported_function->GetWasmCode();