[wasm] Implement the WebAssembly.Module.imports function.

src/wasm/wasm-js.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/api-natives.h"
 #include "src/api.h"
 #include "src/asmjs/asm-js.h"
 #include "src/asmjs/asm-typer.h"
 #include "src/asmjs/asm-wasm-builder.h"
 #include "src/assert-scope.h"
@@ skipping 214 matching lines @@
       i_isolate, thrower, i_module_obj, ffi, memory);
   if (instance.is_null()) {
     if (!thrower->error())
       thrower->RuntimeError("Could not instantiate module");
     return nothing;
   }
   DCHECK(!i_isolate->has_pending_exception());
   return Utils::ToLocal(instance.ToHandleChecked());
 }
 
+void WebAssemblyModuleImports(const v8::FunctionCallbackInfo<v8::Value>& args) {
+  HandleScope scope(args.GetIsolate());
+  v8::Isolate* isolate = args.GetIsolate();
+  i::Isolate* i_isolate = reinterpret_cast<i::Isolate*>(isolate);
+
+  ErrorThrower thrower(i_isolate, "WebAssembly.Instance()");
+
+  if (args.Length() < 1) {
+    thrower.TypeError("Argument 0 must be a WebAssembly.Module");
+    return;
+  }
+
+  Local<Context> context = isolate->GetCurrentContext();
+  i::Handle<i::Context> i_context = Utils::OpenHandle(*context);
+  if (!BrandCheck(isolate, Utils::OpenHandle(*args[0]),
+                  i::Handle<i::Symbol>(i_context->wasm_module_sym()),
+                  "Argument 0 must be a WebAssembly.Module")) {
+    return;
+  }
+
+  Local<Object> module_obj = Local<Object>::Cast(args[0]);
+  i::Handle<i::WasmModuleObject> i_module_obj =
+      i::Handle<i::WasmModuleObject>::cast(v8::Utils::OpenHandle(*module_obj));
+
+  i::Handle<i::JSArray> imports = i::wasm::GetImports(i_isolate, i_module_obj);
+
+  v8::ReturnValue<v8::Value> return_value = args.GetReturnValue();
+  return_value.Set(Utils::ToLocal(imports));
+}
+
 void WebAssemblyInstanceCtor(const v8::FunctionCallbackInfo<v8::Value>& args) {
   HandleScope scope(args.GetIsolate());
   v8::Isolate* isolate = args.GetIsolate();
   i::Isolate* i_isolate = reinterpret_cast<i::Isolate*>(isolate);
 
   ErrorThrower thrower(i_isolate, "WebAssembly.Instance()");
 
   if (args.Length() < 1) {
     thrower.TypeError("Argument 0 must be a WebAssembly.Module");
     return;
@@ skipping 469 matching lines @@
       InstallFunc(isolate, webassembly, "Module", WebAssemblyModule, 1);
   context->set_wasm_module_constructor(*module_constructor);
   Handle<JSObject> module_proto =
       factory->NewJSObject(module_constructor, TENURED);
   i::Handle<i::Map> map = isolate->factory()->NewMap(
       i::JS_OBJECT_TYPE, i::JSObject::kHeaderSize +
                              WasmModuleObject::kFieldCount * i::kPointerSize);
   JSFunction::SetInitialMap(module_constructor, map, module_proto);
   JSObject::AddProperty(module_proto, isolate->factory()->constructor_string(),
                         module_constructor, DONT_ENUM);
+  InstallFunc(isolate, module_constructor, "imports", WebAssemblyModuleImports,
+              1);
 
   // Setup Instance
   Handle<JSFunction> instance_constructor =
       InstallFunc(isolate, webassembly, "Instance", WebAssemblyInstanceCtor, 1);
   context->set_wasm_instance_constructor(*instance_constructor);
 
   // Setup Table
   Handle<JSFunction> table_constructor =
       InstallFunc(isolate, webassembly, "Table", WebAssemblyTable, 1);
   context->set_wasm_table_constructor(*table_constructor);
@@ skipping 98 matching lines @@
   i::Handle<i::Symbol> symbol(isolate->context()->wasm_memory_sym(), isolate);
   return HasBrand(value, symbol);
 }
 
 bool WasmJs::IsWasmTableObject(Isolate* isolate, Handle<Object> value) {
   i::Handle<i::Symbol> symbol(isolate->context()->wasm_table_sym(), isolate);
   return HasBrand(value, symbol);
 }
 }  // namespace internal
 }  // namespace v8