LibWeb: Port WebAssembly.Memory to IDL

Author: https://github.com/trflynn89
Commit: https://github.com/SerenityOS/serenity/commit/ca96f8e364
Pull-request: https://github.com/SerenityOS/serenity/pull/17878
Reviewed-by: https://github.com/alimpfard ✅

Meta/Lagom/Tools/CodeGenerators/LibWeb/BindingsGenerator/IDLGenerators.cpp

@@ -38,6 +38,7 @@ static bool is_platform_object(Type const& type)
         "FormData"sv,
         "ImageData"sv,
         "Instance"sv,
+        "Memory"sv,
         "Module"sv,
         "MutationRecord"sv,
         "NamedNodeMap"sv,

Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateWindowOrWorkerInterfaces.cpp

@@ -103,7 +103,6 @@ class @legacy_constructor_class@;)~~~");
     // FIXME: Special case WebAssembly. We should convert WASM to use IDL.
     {
         auto gen = generator.fork();
-        add_interface(gen, "WebAssemblyMemoryPrototype"sv, "WebAssemblyMemoryConstructor"sv, {});
         add_interface(gen, "WebAssemblyTablePrototype"sv, "WebAssemblyTableConstructor"sv, {});
     }
 
@@ -153,8 +152,6 @@ static ErrorOr<void> generate_intrinsic_definitions(StringView output_path, Vect
 
     // FIXME: Special case WebAssembly. We should convert WASM to use IDL.
     generator.append(R"~~~(
-#include <LibWeb/WebAssembly/WebAssemblyMemoryConstructor.h>
-#include <LibWeb/WebAssembly/WebAssemblyMemoryPrototype.h>
 #include <LibWeb/WebAssembly/WebAssemblyTableConstructor.h>
 #include <LibWeb/WebAssembly/WebAssemblyTablePrototype.h>)~~~");
 
@@ -225,7 +222,6 @@ void Intrinsics::create_web_prototype_and_constructor<@prototype_class@>(JS::Rea
     // FIXME: Special case WebAssembly. We should convert WASM to use IDL.
     {
         auto gen = generator.fork();
-        add_interface(gen, "WebAssembly.Memory"sv, "WebAssemblyMemoryPrototype"sv, "WebAssemblyMemoryConstructor"sv, {});
         add_interface(gen, "WebAssembly.Table"sv, "WebAssemblyTablePrototype"sv, "WebAssemblyTableConstructor"sv, {});
     }
 

Userland/Libraries/LibWeb/CMakeLists.txt

@@ -443,9 +443,8 @@ set(SOURCES
     URL/URLSearchParams.cpp
     URL/URLSearchParamsIterator.cpp
     WebAssembly/Instance.cpp
+    WebAssembly/Memory.cpp
     WebAssembly/Module.cpp
-    WebAssembly/WebAssemblyMemoryConstructor.cpp
-    WebAssembly/WebAssemblyMemoryPrototype.cpp
     WebAssembly/WebAssemblyObject.cpp
     WebAssembly/WebAssemblyTableConstructor.cpp
     WebAssembly/WebAssemblyTableObject.cpp

Userland/Libraries/LibWeb/Forward.h

@@ -483,6 +483,7 @@ class ResourceLoader;
 
 namespace Web::WebAssembly {
 class Instance;
+class Memory;
 class Module;
 }
 

Userland/Libraries/LibWeb/WebAssembly/Instance.cpp

@@ -13,6 +13,7 @@
 #include <LibWeb/Bindings/InstancePrototype.h>
 #include <LibWeb/Bindings/Intrinsics.h>
 #include <LibWeb/WebAssembly/Instance.h>
+#include <LibWeb/WebAssembly/Memory.h>
 #include <LibWeb/WebAssembly/Module.h>
 #include <LibWeb/WebAssembly/WebAssemblyObject.h>
 #include <LibWeb/WebAssembly/WebAssemblyTableObject.h>
@@ -60,9 +61,9 @@ JS::ThrowCompletionOr<void> Instance::initialize(JS::Realm& realm)
                 return {};
             },
             [&](Wasm::MemoryAddress const& address) -> JS::ThrowCompletionOr<void> {
-                Optional<JS::GCPtr<Bindings::WebAssemblyMemoryObject>> object = cache.memory_instances.get(address);
+                Optional<JS::GCPtr<Memory>> object = cache.memory_instances.get(address);
                 if (!object.has_value()) {
-                    object = MUST_OR_THROW_OOM(heap().allocate<Web::Bindings::WebAssemblyMemoryObject>(realm, realm, address));
+                    object = MUST_OR_THROW_OOM(heap().allocate<Memory>(realm, realm, address));
                     cache.memory_instances.set(address, *object);
                 }
 

Userland/Libraries/LibWeb/WebAssembly/Memory.cpp

@@ -0,0 +1,77 @@
+/*
+ * Copyright (c) 2021, Ali Mohammad Pur <mpfard@serenityos.org>
+ * Copyright (c) 2023, Tim Flynn <trflynn89@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibJS/Runtime/Realm.h>
+#include <LibJS/Runtime/VM.h>
+#include <LibWasm/Types.h>
+#include <LibWeb/Bindings/Intrinsics.h>
+#include <LibWeb/WebAssembly/Memory.h>
+#include <LibWeb/WebAssembly/WebAssemblyObject.h>
+
+namespace Web::WebAssembly {
+
+WebIDL::ExceptionOr<JS::NonnullGCPtr<Memory>> Memory::construct_impl(JS::Realm& realm, MemoryDescriptor& descriptor)
+{
+    auto& vm = realm.vm();
+
+    Wasm::Limits limits { descriptor.initial, move(descriptor.maximum) };
+    Wasm::MemoryType memory_type { move(limits) };
+
+    auto address = Bindings::WebAssemblyObject::s_abstract_machine.store().allocate(memory_type);
+    if (!address.has_value())
+        return vm.throw_completion<JS::TypeError>("Wasm Memory allocation failed"sv);
+
+    return MUST_OR_THROW_OOM(vm.heap().allocate<Memory>(realm, realm, *address));
+}
+
+Memory::Memory(JS::Realm& realm, Wasm::MemoryAddress address)
+    : Bindings::PlatformObject(realm)
+    , m_address(address)
+{
+}
+
+JS::ThrowCompletionOr<void> Memory::initialize(JS::Realm& realm)
+{
+    MUST_OR_THROW_OOM(Base::initialize(realm));
+    set_prototype(&Bindings::ensure_web_prototype<Bindings::MemoryPrototype>(realm, "WebAssembly.Memory"sv));
+
+    return {};
+}
+
+// https://webassembly.github.io/spec/js-api/#dom-memory-grow
+WebIDL::ExceptionOr<u32> Memory::grow(u32 delta)
+{
+    auto& vm = this->vm();
+
+    auto* memory = Bindings::WebAssemblyObject::s_abstract_machine.store().get(address());
+    if (!memory)
+        return vm.throw_completion<JS::RangeError>("Could not find the memory instance to grow"sv);
+
+    auto previous_size = memory->size() / Wasm::Constants::page_size;
+    if (!memory->grow(delta * Wasm::Constants::page_size))
+        return vm.throw_completion<JS::RangeError>("Memory.grow() grows past the stated limit of the memory instance"sv);
+
+    return previous_size;
+}
+
+// https://webassembly.github.io/spec/js-api/#dom-memory-buffer
+WebIDL::ExceptionOr<JS::NonnullGCPtr<JS::ArrayBuffer>> Memory::buffer() const
+{
+    auto& vm = this->vm();
+    auto& realm = *vm.current_realm();
+
+    auto* memory = Bindings::WebAssemblyObject::s_abstract_machine.store().get(address());
+    if (!memory)
+        return vm.throw_completion<JS::RangeError>("Could not find the memory instance"sv);
+
+    auto array_buffer = JS::ArrayBuffer::create(realm, &memory->data());
+    array_buffer->set_detach_key(MUST_OR_THROW_OOM(JS::PrimitiveString::create(vm, "WebAssembly.Memory"sv)));
+
+    return array_buffer;
+}
+
+}

Userland/Libraries/LibWeb/WebAssembly/Memory.h

@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2021, Ali Mohammad Pur <mpfard@serenityos.org>
+ * Copyright (c) 2023, Tim Flynn <trflynn89@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Optional.h>
+#include <LibJS/Forward.h>
+#include <LibJS/Heap/GCPtr.h>
+#include <LibJS/Runtime/ArrayBuffer.h>
+#include <LibWasm/AbstractMachine/AbstractMachine.h>
+#include <LibWeb/Bindings/ExceptionOrUtils.h>
+#include <LibWeb/Bindings/PlatformObject.h>
+
+namespace Web::WebAssembly {
+
+struct MemoryDescriptor {
+    u32 initial { 0 };
+    Optional<u32> maximum;
+};
+
+class Memory : public Bindings::PlatformObject {
+    WEB_PLATFORM_OBJECT(Memory, Bindings::PlatformObject);
+
+public:
+    static WebIDL::ExceptionOr<JS::NonnullGCPtr<Memory>> construct_impl(JS::Realm&, MemoryDescriptor& descriptor);
+
+    WebIDL::ExceptionOr<u32> grow(u32 delta);
+    WebIDL::ExceptionOr<JS::NonnullGCPtr<JS::ArrayBuffer>> buffer() const;
+
+    Wasm::MemoryAddress address() const { return m_address; }
+
+private:
+    Memory(JS::Realm&, Wasm::MemoryAddress);
+
+    virtual JS::ThrowCompletionOr<void> initialize(JS::Realm&) override;
+
+    Wasm::MemoryAddress m_address;
+};
+
+}

Userland/Libraries/LibWeb/WebAssembly/Memory.idl

@@ -0,0 +1,14 @@
+dictionary MemoryDescriptor {
+    required [EnforceRange] unsigned long initial;
+    [EnforceRange] unsigned long maximum;
+};
+
+// https://webassembly.github.io/spec/js-api/#memories
+[LegacyNamespace=WebAssembly, Exposed=*]
+interface Memory {
+    constructor(MemoryDescriptor descriptor);
+
+    unsigned long grow([EnforceRange] unsigned long delta);
+
+    readonly attribute ArrayBuffer buffer;
+};

Userland/Libraries/LibWeb/WebAssembly/WebAssemblyMemoryConstructor.cpp

@@ -1,63 +0,0 @@
-/*
- * Copyright (c) 2021, Ali Mohammad Pur <mpfard@serenityos.org>
- *
- * SPDX-License-Identifier: BSD-2-Clause
- */
-
-#include <LibWeb/Bindings/Intrinsics.h>
-#include <LibWeb/WebAssembly/WebAssemblyMemoryConstructor.h>
-#include <LibWeb/WebAssembly/WebAssemblyMemoryPrototype.h>
-#include <LibWeb/WebAssembly/WebAssemblyObject.h>
-
-namespace Web::Bindings {
-
-WebAssemblyMemoryConstructor::WebAssemblyMemoryConstructor(JS::Realm& realm)
-    : NativeFunction(*realm.intrinsics().function_prototype())
-{
-}
-
-WebAssemblyMemoryConstructor::~WebAssemblyMemoryConstructor() = default;
-
-JS::ThrowCompletionOr<JS::Value> WebAssemblyMemoryConstructor::call()
-{
-    return vm().throw_completion<JS::TypeError>(JS::ErrorType::ConstructorWithoutNew, "WebAssembly.Memory");
-}
-
-JS::ThrowCompletionOr<JS::NonnullGCPtr<JS::Object>> WebAssemblyMemoryConstructor::construct(FunctionObject&)
-{
-    auto& vm = this->vm();
-    auto& realm = *vm.current_realm();
-
-    auto descriptor = TRY(vm.argument(0).to_object(vm));
-    auto initial_value = TRY(descriptor->get("initial"));
-    auto maximum_value = TRY(descriptor->get("maximum"));
-
-    if (!initial_value.is_number())
-        return vm.throw_completion<JS::TypeError>(JS::ErrorType::NotAnObjectOfType, "Number");
-
-    u32 initial = TRY(initial_value.to_u32(vm));
-
-    Optional<u32> maximum;
-
-    if (!maximum_value.is_undefined())
-        maximum = TRY(maximum_value.to_u32(vm));
-
-    auto address = WebAssemblyObject::s_abstract_machine.store().allocate(Wasm::MemoryType { Wasm::Limits { initial, maximum } });
-    if (!address.has_value())
-        return vm.throw_completion<JS::TypeError>("Wasm Memory allocation failed"sv);
-
-    return MUST_OR_THROW_OOM(vm.heap().allocate<WebAssemblyMemoryObject>(realm, realm, *address));
-}
-
-JS::ThrowCompletionOr<void> WebAssemblyMemoryConstructor::initialize(JS::Realm& realm)
-{
-    auto& vm = this->vm();
-
-    MUST_OR_THROW_OOM(NativeFunction::initialize(realm));
-    define_direct_property(vm.names.prototype, &Bindings::ensure_web_prototype<WebAssemblyMemoryPrototype>(realm, "WebAssembly.Memory"), 0);
-    define_direct_property(vm.names.length, JS::Value(1), JS::Attribute::Configurable);
-
-    return {};
-}
-
-}

Userland/Libraries/LibWeb/WebAssembly/WebAssemblyMemoryConstructor.h

@@ -1,28 +0,0 @@
-/*
- * Copyright (c) 2021, Ali Mohammad Pur <mpfard@serenityos.org>
- *
- * SPDX-License-Identifier: BSD-2-Clause
- */
-
-#pragma once
-
-#include <LibJS/Runtime/NativeFunction.h>
-
-namespace Web::Bindings {
-
-class WebAssemblyMemoryConstructor : public JS::NativeFunction {
-    JS_OBJECT(WebAssemblyMemoryConstructor, JS::NativeFunction);
-
-public:
-    explicit WebAssemblyMemoryConstructor(JS::Realm&);
-    virtual JS::ThrowCompletionOr<void> initialize(JS::Realm&) override;
-    virtual ~WebAssemblyMemoryConstructor() override;
-
-    virtual JS::ThrowCompletionOr<JS::Value> call() override;
-    virtual JS::ThrowCompletionOr<JS::NonnullGCPtr<JS::Object>> construct(JS::FunctionObject& new_target) override;
-
-private:
-    virtual bool has_constructor() const override { return true; }
-};
-
-}

Userland/Libraries/LibWeb/WebAssembly/WebAssemblyMemoryPrototype.cpp

@@ -1,60 +0,0 @@
-/*
- * Copyright (c) 2021, Ali Mohammad Pur <mpfard@serenityos.org>
- *
- * SPDX-License-Identifier: BSD-2-Clause
- */
-
-#include <AK/TypeCasts.h>
-#include <LibJS/Runtime/TypedArray.h>
-#include <LibWeb/WebAssembly/WebAssemblyMemoryPrototype.h>
-#include <LibWeb/WebAssembly/WebAssemblyObject.h>
-
-namespace Web::Bindings {
-
-JS::ThrowCompletionOr<void> WebAssemblyMemoryPrototype::initialize(JS::Realm& realm)
-{
-    MUST_OR_THROW_OOM(Object::initialize(realm));
-    define_native_accessor(realm, "buffer", buffer_getter, {}, JS::Attribute::Enumerable | JS::Attribute::Configurable);
-    define_native_function(realm, "grow", grow, 1, JS::Attribute::Writable | JS::Attribute::Enumerable | JS::Attribute::Configurable);
-
-    return {};
-}
-
-JS_DEFINE_NATIVE_FUNCTION(WebAssemblyMemoryPrototype::grow)
-{
-    auto page_count = TRY(vm.argument(0).to_u32(vm));
-    auto* this_object = TRY(vm.this_value().to_object(vm));
-    if (!is<WebAssemblyMemoryObject>(this_object))
-        return vm.throw_completion<JS::TypeError>(JS::ErrorType::NotAnObjectOfType, "WebAssembly.Memory");
-    auto* memory_object = static_cast<WebAssemblyMemoryObject*>(this_object);
-    auto address = memory_object->address();
-    auto* memory = WebAssemblyObject::s_abstract_machine.store().get(address);
-    if (!memory)
-        return JS::js_undefined();
-
-    auto previous_size = memory->size() / Wasm::Constants::page_size;
-    if (!memory->grow(page_count * Wasm::Constants::page_size))
-        return vm.throw_completion<JS::TypeError>("Memory.grow() grows past the stated limit of the memory instance"sv);
-
-    return JS::Value(static_cast<u32>(previous_size));
-}
-
-JS_DEFINE_NATIVE_FUNCTION(WebAssemblyMemoryPrototype::buffer_getter)
-{
-    auto& realm = *vm.current_realm();
-
-    auto* this_object = TRY(vm.this_value().to_object(vm));
-    if (!is<WebAssemblyMemoryObject>(this_object))
-        return vm.throw_completion<JS::TypeError>(JS::ErrorType::NotAnObjectOfType, "WebAssembly.Memory");
-    auto* memory_object = static_cast<WebAssemblyMemoryObject*>(this_object);
-    auto address = memory_object->address();
-    auto* memory = WebAssemblyObject::s_abstract_machine.store().get(address);
-    if (!memory)
-        return JS::js_undefined();
-
-    auto array_buffer = JS::ArrayBuffer::create(realm, &memory->data());
-    array_buffer->set_detach_key(MUST_OR_THROW_OOM(JS::PrimitiveString::create(vm, "WebAssembly.Memory"sv)));
-    return array_buffer;
-}
-
-}

Userland/Libraries/LibWeb/WebAssembly/WebAssemblyMemoryPrototype.h

@@ -1,32 +0,0 @@
-/*
- * Copyright (c) 2021, Ali Mohammad Pur <mpfard@serenityos.org>
- *
- * SPDX-License-Identifier: BSD-2-Clause
- */
-
-#pragma once
-
-#include "WebAssemblyMemoryConstructor.h"
-#include <LibJS/Runtime/Object.h>
-#include <LibJS/Runtime/VM.h>
-#include <LibWeb/Forward.h>
-
-namespace Web::Bindings {
-
-class WebAssemblyMemoryPrototype final : public JS::Object {
-    JS_OBJECT(WebAssemblyMemoryPrototype, JS::Object);
-
-public:
-    explicit WebAssemblyMemoryPrototype(JS::Realm& realm)
-        : JS::Object(ConstructWithPrototypeTag::Tag, *realm.intrinsics().object_prototype())
-    {
-    }
-
-    virtual JS::ThrowCompletionOr<void> initialize(JS::Realm&) override;
-
-private:
-    JS_DECLARE_NATIVE_FUNCTION(grow);
-    JS_DECLARE_NATIVE_FUNCTION(buffer_getter);
-};
-
-}

Userland/Libraries/LibWeb/WebAssembly/WebAssemblyObject.cpp

@@ -4,7 +4,6 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
-#include "WebAssemblyMemoryPrototype.h"
 #include "WebAssemblyTableObject.h"
 #include "WebAssemblyTablePrototype.h"
 #include <AK/MemoryStream.h>
@@ -20,8 +19,10 @@
 #include <LibWasm/AbstractMachine/Validator.h>
 #include <LibWeb/Bindings/InstancePrototype.h>
 #include <LibWeb/Bindings/Intrinsics.h>
+#include <LibWeb/Bindings/MemoryPrototype.h>
 #include <LibWeb/Bindings/ModulePrototype.h>
 #include <LibWeb/WebAssembly/Instance.h>
+#include <LibWeb/WebAssembly/Memory.h>
 #include <LibWeb/WebAssembly/Module.h>
 #include <LibWeb/WebAssembly/WebAssemblyObject.h>
 
@@ -42,7 +43,7 @@ JS::ThrowCompletionOr<void> WebAssemblyObject::initialize(JS::Realm& realm)
     define_native_function(realm, "compile", compile, 1, attr);
     define_native_function(realm, "instantiate", instantiate, 1, attr);
 
-    auto& memory_constructor = Bindings::ensure_web_constructor<WebAssemblyMemoryPrototype>(realm, "WebAssembly.Memory"sv);
+    auto& memory_constructor = Bindings::ensure_web_constructor<MemoryPrototype>(realm, "WebAssembly.Memory"sv);
     define_direct_property("Memory", &memory_constructor, JS::Attribute::Writable | JS::Attribute::Configurable);
 
     auto& instance_constructor = Bindings::ensure_web_constructor<InstancePrototype>(realm, "WebAssembly.Instance"sv);
@@ -262,11 +263,11 @@ JS::ThrowCompletionOr<size_t> WebAssemblyObject::instantiate_module(JS::VM& vm,
                     return {};
                 },
                 [&](Wasm::MemoryType const&) -> JS::ThrowCompletionOr<void> {
-                    if (!import_.is_object() || !is<WebAssemblyMemoryObject>(import_.as_object())) {
+                    if (!import_.is_object() || !is<WebAssembly::Memory>(import_.as_object())) {
                         // FIXME: Throw a LinkError instead
                         return vm.throw_completion<JS::TypeError>("LinkError: Expected an instance of WebAssembly.Memory for a memory import"sv);
                     }
-                    auto address = static_cast<WebAssemblyMemoryObject const&>(import_.as_object()).address();
+                    auto address = static_cast<WebAssembly::Memory const&>(import_.as_object()).address();
                     resolved_imports.set(import_name, Wasm::ExternValue { address });
                     return {};
                 },
@@ -472,10 +473,4 @@ JS::NativeFunction* create_native_function(JS::VM& vm, Wasm::FunctionAddress add
     return function;
 }
 
-WebAssemblyMemoryObject::WebAssemblyMemoryObject(JS::Realm& realm, Wasm::MemoryAddress address)
-    : Object(ConstructWithPrototypeTag::Tag, Bindings::ensure_web_prototype<WebAssemblyMemoryPrototype>(realm, "WebAssembly.Memory"))
-    , m_address(address)
-{
-}
-
 }

Userland/Libraries/LibWeb/WebAssembly/WebAssemblyObject.h

@@ -12,7 +12,6 @@
 
 namespace Web::Bindings {
 
-class WebAssemblyMemoryObject;
 class WebAssemblyTableObject;
 JS::ThrowCompletionOr<size_t> parse_module(JS::VM&, JS::Object* buffer);
 JS::NativeFunction* create_native_function(JS::VM&, Wasm::FunctionAddress address, DeprecatedString const& name);
@@ -46,7 +45,7 @@ public:
     //        WebAssemblyModuleObject's and WebAssemblyInstantiatedModuleObject's.
     struct ModuleCache {
         HashMap<Wasm::FunctionAddress, JS::GCPtr<JS::FunctionObject>> function_instances;
-        HashMap<Wasm::MemoryAddress, JS::GCPtr<WebAssemblyMemoryObject>> memory_instances;
+        HashMap<Wasm::MemoryAddress, JS::GCPtr<WebAssembly::Memory>> memory_instances;
         HashMap<Wasm::TableAddress, JS::GCPtr<WebAssemblyTableObject>> table_instances;
     };
     struct GlobalModuleCache {
@@ -66,17 +65,4 @@ private:
     JS_DECLARE_NATIVE_FUNCTION(instantiate);
 };
 
-class WebAssemblyMemoryObject final : public JS::Object {
-    JS_OBJECT(WebAssemblyMemoryObject, JS::Object);
-
-public:
-    WebAssemblyMemoryObject(JS::Realm&, Wasm::MemoryAddress);
-    virtual ~WebAssemblyMemoryObject() override = default;
-
-    auto address() const { return m_address; }
-
-private:
-    Wasm::MemoryAddress m_address;
-};
-
 }

Userland/Libraries/LibWeb/idl_files.cmake

@@ -201,6 +201,7 @@ libweb_js_bindings(UIEvents/WheelEvent)
 libweb_js_bindings(URL/URL)
 libweb_js_bindings(URL/URLSearchParams ITERABLE)
 libweb_js_bindings(WebAssembly/Instance)
+libweb_js_bindings(WebAssembly/Memory)
 libweb_js_bindings(WebAssembly/Module)
 libweb_js_bindings(WebGL/WebGLContextEvent)
 libweb_js_bindings(WebGL/WebGLRenderingContext)