RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-05-20 13:25:08 +00:00
Code Issues Activity Actions

LibJS/JIT: Compile the GetGlobal bytecode instruction

Browse source
This commit is contained in:
Andreas Kling 2023-10-20 12:56:12 +02:00
parent 12898f5aef
commit 3974ce2069
6 changed files with 81 additions and 50 deletions
Download patch file Download diff file Expand all files Collapse all files

53
Userland/Libraries/LibJS/Bytecode/CommonImplementations.cpp
View file

@ -6,6 +6,9 @@
#include <LibJS/Bytecode/CommonImplementations.h>
#include <LibJS/Bytecode/Interpreter.h>
#include <LibJS/Runtime/DeclarativeEnvironment.h>
#include <LibJS/Runtime/GlobalEnvironment.h>
#include <LibJS/Runtime/ObjectEnvironment.h>
namespace JS::Bytecode {
@ -86,4 +89,54 @@ ThrowCompletionOr<Value> get_by_value(Bytecode::Interpreter& interpreter, Value
return TRY(object->internal_get(property_key, base_value));
}
ThrowCompletionOr<Value> get_global(Bytecode::Interpreter& interpreter, IdentifierTableIndex identifier, u32 cache_index)
{
auto& vm = interpreter.vm();
auto& realm = *vm.current_realm();
auto& cache = interpreter.current_executable().global_variable_caches[cache_index];
auto& binding_object = realm.global_environment().object_record().binding_object();
auto& declarative_record = realm.global_environment().declarative_record();
// OPTIMIZATION: If the shape of the object hasn't changed, we can use the cached property offset.
// NOTE: Unique shapes don't change identity, so we compare their serial numbers instead.
auto& shape = binding_object.shape();
if (cache.environment_serial_number == declarative_record.environment_serial_number()
&& &shape == cache.shape
&& (!shape.is_unique() || shape.unique_shape_serial_number() == cache.unique_shape_serial_number)) {
return binding_object.get_direct(cache.property_offset.value());
}
cache.environment_serial_number = declarative_record.environment_serial_number();
auto const& name = interpreter.current_executable().get_identifier(identifier);
if (vm.running_execution_context().script_or_module.has<NonnullGCPtr<Module>>()) {
// NOTE: GetGlobal is used to access variables stored in the module environment and global environment.
// The module environment is checked first since it precedes the global environment in the environment chain.
auto& module_environment = *vm.running_execution_context().script_or_module.get<NonnullGCPtr<Module>>()->environment();
if (TRY(module_environment.has_binding(name))) {
// TODO: Cache offset of binding value
return TRY(module_environment.get_binding_value(vm, name, vm.in_strict_mode()));
}
}
if (TRY(declarative_record.has_binding(name))) {
// TODO: Cache offset of binding value
return TRY(declarative_record.get_binding_value(vm, name, vm.in_strict_mode()));
}
if (TRY(binding_object.has_property(name))) {
CacheablePropertyMetadata cacheable_metadata;
auto value = TRY(binding_object.internal_get(name, js_undefined(), &cacheable_metadata));
if (cacheable_metadata.type == CacheablePropertyMetadata::Type::OwnProperty) {
cache.shape = shape;
cache.property_offset = cacheable_metadata.property_offset.value();
cache.unique_shape_serial_number = shape.unique_shape_serial_number();
}
return value;
}
return vm.throw_completion<ReferenceError>(ErrorType::UnknownIdentifier, name);
}
}