LibWasm: Decouple ModuleInstance from the AbstractMachine

This fixes a FIXME and will allow linking only select modules together,
instead of linking every instantiated module into a big mess of exported
entities :P
This commit is contained in:
Ali Mohammad Pur 2021-05-10 15:40:49 +04:30 committed by Linus Groh
parent 24b2a6c93a
commit efb106069b
Notes: sideshowbarker 2024-07-18 17:39:46 +09:00
4 changed files with 55 additions and 47 deletions

View file

@ -31,18 +31,23 @@ class WebAssemblyModule final : public JS::Object {
JS_OBJECT(WebAssemblyModule, JS::Object); JS_OBJECT(WebAssemblyModule, JS::Object);
public: public:
// FIXME: This should only contain an instantiated module, not the entire abstract machine!
explicit WebAssemblyModule(JS::Object& prototype) explicit WebAssemblyModule(JS::Object& prototype)
: JS::Object(prototype) : JS::Object(prototype)
{ {
} }
static Wasm::AbstractMachine& machine() { return m_machine; }
Wasm::Module& module() { return *m_module; }
Wasm::ModuleInstance& module_instance() { return *m_module_instance; }
static WebAssemblyModule* create(JS::GlobalObject& global_object, Wasm::Module module) static WebAssemblyModule* create(JS::GlobalObject& global_object, Wasm::Module module)
{ {
auto instance = global_object.heap().allocate<WebAssemblyModule>(global_object, *global_object.object_prototype()); auto instance = global_object.heap().allocate<WebAssemblyModule>(global_object, *global_object.object_prototype());
instance->m_module = move(module); instance->m_module = move(module);
if (auto result = instance->m_machine.instantiate(*instance->m_module, {}); result.is_error()) if (auto result = machine().instantiate(*instance->m_module, {}); result.is_error())
global_object.vm().throw_exception<JS::TypeError>(global_object, result.release_error().error); global_object.vm().throw_exception<JS::TypeError>(global_object, result.release_error().error);
else
instance->m_module_instance = result.release_value();
return instance; return instance;
} }
void initialize(JS::GlobalObject&) override; void initialize(JS::GlobalObject&) override;
@ -53,10 +58,13 @@ private:
JS_DECLARE_NATIVE_FUNCTION(get_export); JS_DECLARE_NATIVE_FUNCTION(get_export);
JS_DECLARE_NATIVE_FUNCTION(wasm_invoke); JS_DECLARE_NATIVE_FUNCTION(wasm_invoke);
Wasm::AbstractMachine m_machine; static Wasm::AbstractMachine m_machine;
Optional<Wasm::Module> m_module; Optional<Wasm::Module> m_module;
Optional<Wasm::ModuleInstance> m_module_instance;
}; };
Wasm::AbstractMachine WebAssemblyModule::m_machine;
TESTJS_GLOBAL_FUNCTION(parse_webassembly_module, parseWebAssemblyModule) TESTJS_GLOBAL_FUNCTION(parse_webassembly_module, parseWebAssemblyModule)
{ {
auto object = vm.argument(0).to_object(global_object); auto object = vm.argument(0).to_object(global_object);
@ -123,7 +131,7 @@ JS_DEFINE_NATIVE_FUNCTION(WebAssemblyModule::get_export)
return {}; return {};
} }
auto instance = static_cast<WebAssemblyModule*>(object); auto instance = static_cast<WebAssemblyModule*>(object);
for (auto& entry : instance->m_machine.module_instance().exports()) { for (auto& entry : instance->module_instance().exports()) {
if (entry.name() == name) { if (entry.name() == name) {
auto& value = entry.value(); auto& value = entry.value();
if (auto ptr = value.get_pointer<Wasm::FunctionAddress>()) if (auto ptr = value.get_pointer<Wasm::FunctionAddress>())
@ -151,7 +159,7 @@ JS_DEFINE_NATIVE_FUNCTION(WebAssemblyModule::wasm_invoke)
} }
auto instance = static_cast<WebAssemblyModule*>(object); auto instance = static_cast<WebAssemblyModule*>(object);
Wasm::FunctionAddress function_address { address }; Wasm::FunctionAddress function_address { address };
auto function_instance = instance->m_machine.store().get(function_address); auto function_instance = WebAssemblyModule::machine().store().get(function_address);
if (!function_instance) { if (!function_instance) {
vm.throw_exception<JS::TypeError>(global_object, "Invalid function address"); vm.throw_exception<JS::TypeError>(global_object, "Invalid function address");
return {}; return {};
@ -194,7 +202,7 @@ JS_DEFINE_NATIVE_FUNCTION(WebAssemblyModule::wasm_invoke)
} }
} }
auto result = instance->m_machine.invoke(function_address, arguments); auto result = WebAssemblyModule::machine().invoke(function_address, arguments);
if (result.is_trap()) { if (result.is_trap()) {
vm.throw_exception<JS::TypeError>(global_object, "Execution trapped"); vm.throw_exception<JS::TypeError>(global_object, "Execution trapped");
return {}; return {};

View file

@ -85,10 +85,11 @@ GlobalInstance* Store::get(GlobalAddress address)
InstantiationResult AbstractMachine::instantiate(const Module& module, Vector<ExternValue> externs) InstantiationResult AbstractMachine::instantiate(const Module& module, Vector<ExternValue> externs)
{ {
ModuleInstance main_module_instance;
Optional<InstantiationResult> instantiation_result; Optional<InstantiationResult> instantiation_result;
module.for_each_section_of_type<TypeSection>([&](const TypeSection& section) { module.for_each_section_of_type<TypeSection>([&](const TypeSection& section) {
m_module_instance.types() = section.types(); main_module_instance.types() = section.types();
}); });
// FIXME: Validate stuff // FIXME: Validate stuff
@ -121,8 +122,8 @@ InstantiationResult AbstractMachine::instantiate(const Module& module, Vector<Ex
} }
}); });
if (auto result = allocate_all(module, externs, global_values); result.is_error()) { if (auto result = allocate_all(module, main_module_instance, externs, global_values); result.has_value()) {
return result.error(); return result.release_value();
} }
module.for_each_section_of_type<ElementSection>([&](const ElementSection&) { module.for_each_section_of_type<ElementSection>([&](const ElementSection&) {
@ -136,7 +137,7 @@ InstantiationResult AbstractMachine::instantiate(const Module& module, Vector<Ex
segment.value().visit( segment.value().visit(
[&](const DataSection::Data::Active& data) { [&](const DataSection::Data::Active& data) {
auto frame = make<Frame>( auto frame = make<Frame>(
m_module_instance, main_module_instance,
Vector<Value> {}, Vector<Value> {},
data.offset, data.offset,
1); 1);
@ -150,11 +151,11 @@ InstantiationResult AbstractMachine::instantiate(const Module& module, Vector<Ex
[&](const ExternAddress&) { instantiation_result = InstantiationError { "Data segment offset returned an address" }; }); [&](const ExternAddress&) { instantiation_result = InstantiationError { "Data segment offset returned an address" }; });
if (instantiation_result.has_value() && instantiation_result->is_error()) if (instantiation_result.has_value() && instantiation_result->is_error())
return; return;
if (m_module_instance.memories().size() <= data.index.value()) { if (main_module_instance.memories().size() <= data.index.value()) {
instantiation_result = InstantiationError { String::formatted("Data segment referenced out-of-bounds memory ({}) of max {} entries", data.index.value(), m_module_instance.memories().size()) }; instantiation_result = InstantiationError { String::formatted("Data segment referenced out-of-bounds memory ({}) of max {} entries", data.index.value(), main_module_instance.memories().size()) };
return; return;
} }
auto address = m_module_instance.memories()[data.index.value()]; auto address = main_module_instance.memories()[data.index.value()];
if (auto instance = m_store.get(address)) { if (auto instance = m_store.get(address)) {
if (instance->type().limits().max().value_or(data.init.size() + offset + 1) <= data.init.size() + offset) { if (instance->type().limits().max().value_or(data.init.size() + offset + 1) <= data.init.size() + offset) {
instantiation_result = InstantiationError { String::formatted("Data segment attempted to write to out-of-bounds memory ({}) of max {} bytes", data.init.size() + offset, instance->type().limits().max().value()) }; instantiation_result = InstantiationError { String::formatted("Data segment attempted to write to out-of-bounds memory ({}) of max {} bytes", data.init.size() + offset, instance->type().limits().max().value()) };
@ -171,7 +172,7 @@ InstantiationResult AbstractMachine::instantiate(const Module& module, Vector<Ex
}); });
module.for_each_section_of_type<StartSection>([&](const StartSection& section) { module.for_each_section_of_type<StartSection>([&](const StartSection& section) {
auto& functions = m_module_instance.functions(); auto& functions = main_module_instance.functions();
auto index = section.function().index(); auto index = section.function().index();
if (functions.size() <= index.value()) { if (functions.size() <= index.value()) {
instantiation_result = InstantiationError { String::formatted("Start section function referenced invalid index {} of max {} entries", index.value(), functions.size()) }; instantiation_result = InstantiationError { String::formatted("Start section function referenced invalid index {} of max {} entries", index.value(), functions.size()) };
@ -180,34 +181,34 @@ InstantiationResult AbstractMachine::instantiate(const Module& module, Vector<Ex
invoke(functions[index.value()], {}); invoke(functions[index.value()], {});
}); });
return instantiation_result.value_or({}); return instantiation_result.value_or(move(main_module_instance));
} }
InstantiationResult AbstractMachine::allocate_all(const Module& module, Vector<ExternValue>& externs, Vector<Value>& global_values) Optional<InstantiationError> AbstractMachine::allocate_all(const Module& module, ModuleInstance& module_instance, Vector<ExternValue>& externs, Vector<Value>& global_values)
{ {
Optional<InstantiationResult> result; Optional<InstantiationError> result;
for (auto& entry : externs) { for (auto& entry : externs) {
entry.visit( entry.visit(
[&](const FunctionAddress& address) { m_module_instance.functions().append(address); }, [&](const FunctionAddress& address) { module_instance.functions().append(address); },
[&](const TableAddress& address) { m_module_instance.tables().append(address); }, [&](const TableAddress& address) { module_instance.tables().append(address); },
[&](const MemoryAddress& address) { m_module_instance.memories().append(address); }, [&](const MemoryAddress& address) { module_instance.memories().append(address); },
[&](const GlobalAddress& address) { m_module_instance.globals().append(address); }); [&](const GlobalAddress& address) { module_instance.globals().append(address); });
} }
// FIXME: What if this fails? // FIXME: What if this fails?
for (auto& func : module.functions()) { for (auto& func : module.functions()) {
auto address = m_store.allocate(m_module_instance, func); auto address = m_store.allocate(module_instance, func);
VERIFY(address.has_value()); VERIFY(address.has_value());
m_module_instance.functions().append(*address); module_instance.functions().append(*address);
} }
module.for_each_section_of_type<TableSection>([&](const TableSection& section) { module.for_each_section_of_type<TableSection>([&](const TableSection& section) {
for (auto& table : section.tables()) { for (auto& table : section.tables()) {
auto table_address = m_store.allocate(table.type()); auto table_address = m_store.allocate(table.type());
VERIFY(table_address.has_value()); VERIFY(table_address.has_value());
m_module_instance.tables().append(*table_address); module_instance.tables().append(*table_address);
} }
}); });
@ -215,7 +216,7 @@ InstantiationResult AbstractMachine::allocate_all(const Module& module, Vector<E
for (auto& memory : section.memories()) { for (auto& memory : section.memories()) {
auto memory_address = m_store.allocate(memory.type()); auto memory_address = m_store.allocate(memory.type());
VERIFY(memory_address.has_value()); VERIFY(memory_address.has_value());
m_module_instance.memories().append(*memory_address); module_instance.memories().append(*memory_address);
} }
}); });
@ -224,7 +225,7 @@ InstantiationResult AbstractMachine::allocate_all(const Module& module, Vector<E
for (auto& entry : section.entries()) { for (auto& entry : section.entries()) {
auto address = m_store.allocate(entry.type(), global_values[index]); auto address = m_store.allocate(entry.type(), global_values[index]);
VERIFY(address.has_value()); VERIFY(address.has_value());
m_module_instance.globals().append(*address); module_instance.globals().append(*address);
index++; index++;
} }
}); });
@ -234,28 +235,28 @@ InstantiationResult AbstractMachine::allocate_all(const Module& module, Vector<E
Variant<FunctionAddress, TableAddress, MemoryAddress, GlobalAddress, Empty> address { Empty {} }; Variant<FunctionAddress, TableAddress, MemoryAddress, GlobalAddress, Empty> address { Empty {} };
entry.description().visit( entry.description().visit(
[&](const FunctionIndex& index) { [&](const FunctionIndex& index) {
if (m_module_instance.functions().size() > index.value()) if (module_instance.functions().size() > index.value())
address = FunctionAddress { m_module_instance.functions()[index.value()] }; address = FunctionAddress { module_instance.functions()[index.value()] };
else else
dbgln("Failed to export '{}', the exported address ({}) was out of bounds (min: 0, max: {})", entry.name(), index.value(), m_module_instance.functions().size()); dbgln("Failed to export '{}', the exported address ({}) was out of bounds (min: 0, max: {})", entry.name(), index.value(), module_instance.functions().size());
}, },
[&](const TableIndex& index) { [&](const TableIndex& index) {
if (m_module_instance.tables().size() > index.value()) if (module_instance.tables().size() > index.value())
address = TableAddress { m_module_instance.tables()[index.value()] }; address = TableAddress { module_instance.tables()[index.value()] };
else else
dbgln("Failed to export '{}', the exported address ({}) was out of bounds (min: 0, max: {})", entry.name(), index.value(), m_module_instance.tables().size()); dbgln("Failed to export '{}', the exported address ({}) was out of bounds (min: 0, max: {})", entry.name(), index.value(), module_instance.tables().size());
}, },
[&](const MemoryIndex& index) { [&](const MemoryIndex& index) {
if (m_module_instance.memories().size() > index.value()) if (module_instance.memories().size() > index.value())
address = MemoryAddress { m_module_instance.memories()[index.value()] }; address = MemoryAddress { module_instance.memories()[index.value()] };
else else
dbgln("Failed to export '{}', the exported address ({}) was out of bounds (min: 0, max: {})", entry.name(), index.value(), m_module_instance.memories().size()); dbgln("Failed to export '{}', the exported address ({}) was out of bounds (min: 0, max: {})", entry.name(), index.value(), module_instance.memories().size());
}, },
[&](const GlobalIndex& index) { [&](const GlobalIndex& index) {
if (m_module_instance.globals().size() > index.value()) if (module_instance.globals().size() > index.value())
address = GlobalAddress { m_module_instance.globals()[index.value()] }; address = GlobalAddress { module_instance.globals()[index.value()] };
else else
dbgln("Failed to export '{}', the exported address ({}) was out of bounds (min: 0, max: {})", entry.name(), index.value(), m_module_instance.globals().size()); dbgln("Failed to export '{}', the exported address ({}) was out of bounds (min: 0, max: {})", entry.name(), index.value(), module_instance.globals().size());
}); });
if (address.has<Empty>()) { if (address.has<Empty>()) {
@ -263,14 +264,14 @@ InstantiationResult AbstractMachine::allocate_all(const Module& module, Vector<E
continue; continue;
} }
m_module_instance.exports().append(ExportInstance { module_instance.exports().append(ExportInstance {
entry.name(), entry.name(),
move(address).downcast<FunctionAddress, TableAddress, MemoryAddress, GlobalAddress>(), move(address).downcast<FunctionAddress, TableAddress, MemoryAddress, GlobalAddress>(),
}); });
} }
}); });
return result.value_or({}); return result;
} }
Result AbstractMachine::invoke(FunctionAddress address, Vector<Value> arguments) Result AbstractMachine::invoke(FunctionAddress address, Vector<Value> arguments)

View file

@ -15,7 +15,6 @@ namespace Wasm {
struct InstantiationError { struct InstantiationError {
String error { "Unknown error" }; String error { "Unknown error" };
}; };
using InstantiationResult = Result<void, InstantiationError>;
TYPEDEF_DISTINCT_NUMERIC_GENERAL(u64, true, true, false, false, false, true, FunctionAddress); TYPEDEF_DISTINCT_NUMERIC_GENERAL(u64, true, true, false, false, false, true, FunctionAddress);
TYPEDEF_DISTINCT_NUMERIC_GENERAL(u64, true, true, false, false, false, true, ExternAddress); TYPEDEF_DISTINCT_NUMERIC_GENERAL(u64, true, true, false, false, false, true, ExternAddress);
@ -419,6 +418,8 @@ private:
Vector<EntryType> m_data; Vector<EntryType> m_data;
}; };
using InstantiationResult = AK::Result<ModuleInstance, InstantiationError>;
class AbstractMachine { class AbstractMachine {
public: public:
explicit AbstractMachine() = default; explicit AbstractMachine() = default;
@ -427,14 +428,11 @@ public:
InstantiationResult instantiate(const Module&, Vector<ExternValue>); InstantiationResult instantiate(const Module&, Vector<ExternValue>);
Result invoke(FunctionAddress, Vector<Value>); Result invoke(FunctionAddress, Vector<Value>);
auto& module_instance() const { return m_module_instance; }
auto& module_instance() { return m_module_instance; }
auto& store() const { return m_store; } auto& store() const { return m_store; }
auto& store() { return m_store; } auto& store() { return m_store; }
private: private:
InstantiationResult allocate_all(const Module&, Vector<ExternValue>&, Vector<Value>& global_values); Optional<InstantiationError> allocate_all(const Module&, ModuleInstance&, Vector<ExternValue>&, Vector<Value>& global_values);
ModuleInstance m_module_instance;
Store m_store; Store m_store;
}; };

View file

@ -70,6 +70,7 @@ int main(int argc, char* argv[])
warnln("Module instantiation failed: {}", result.error().error); warnln("Module instantiation failed: {}", result.error().error);
return 1; return 1;
} }
auto module_instance = result.release_value();
auto stream = Core::OutputFileStream::standard_output(); auto stream = Core::OutputFileStream::standard_output();
auto print_func = [&](const auto& address) { auto print_func = [&](const auto& address) {
@ -90,7 +91,7 @@ int main(int argc, char* argv[])
}; };
if (print) { if (print) {
// Now, let's dump the functions! // Now, let's dump the functions!
for (auto& address : machine.module_instance().functions()) { for (auto& address : module_instance.functions()) {
print_func(address); print_func(address);
} }
} }
@ -98,7 +99,7 @@ int main(int argc, char* argv[])
if (!exported_function_to_execute.is_empty()) { if (!exported_function_to_execute.is_empty()) {
Optional<Wasm::FunctionAddress> run_address; Optional<Wasm::FunctionAddress> run_address;
Vector<Wasm::Value> values; Vector<Wasm::Value> values;
for (auto& entry : machine.module_instance().exports()) { for (auto& entry : module_instance.exports()) {
if (entry.name() == exported_function_to_execute) { if (entry.name() == exported_function_to_execute) {
if (auto addr = entry.value().get_pointer<Wasm::FunctionAddress>()) if (auto addr = entry.value().get_pointer<Wasm::FunctionAddress>())
run_address = *addr; run_address = *addr;