LibJS: Move the GlobalEnvironment from GlobalObject to Realm

This is where the spec wants to have it. Requires a couple of hacks as
currently everything that needs a Realm actually has a GlobalObject, so
we need to go via the Interpreter.

Userland/Libraries/LibJS/Bytecode/Interpreter.cpp

@@ -12,6 +12,7 @@
 #include <LibJS/Bytecode/Op.h>
 #include <LibJS/Runtime/GlobalEnvironment.h>
 #include <LibJS/Runtime/GlobalObject.h>
+#include <LibJS/Runtime/Realm.h>
 
 namespace JS::Bytecode {
 
@@ -50,8 +51,8 @@ Value Interpreter::run(Executable const& executable, BasicBlock const* entry_poi
         execution_context.this_value = &global_object();
         static FlyString global_execution_context_name = "(*BC* global execution context)";
         execution_context.function_name = global_execution_context_name;
-        execution_context.lexical_environment = &global_object().environment();
+        execution_context.lexical_environment = &m_realm.global_environment();
-        execution_context.variable_environment = &global_object().environment();
+        execution_context.variable_environment = &m_realm.global_environment();
         VERIFY(!vm().exception());
         // FIXME: How do we know if we're in strict mode? Maybe the Bytecode::Block should know this?
         // execution_context.is_strict_mode = ???;

Userland/Libraries/LibJS/Interpreter.cpp

@@ -37,6 +37,8 @@ Interpreter::~Interpreter()
 
 void Interpreter::run(GlobalObject& global_object, const Program& program)
 {
+    // FIXME: Why does this receive a GlobalObject? Interpreter has one already, and this might not be in sync with the Realm's GlobalObject.
+
     auto& vm = this->vm();
     VERIFY(!vm.exception());
 
@@ -49,8 +51,8 @@ void Interpreter::run(GlobalObject& global_object, const Program& program)
     execution_context.this_value = &global_object;
     static FlyString global_execution_context_name = "(global execution context)";
     execution_context.function_name = global_execution_context_name;
-    execution_context.lexical_environment = &global_object.environment();
+    execution_context.lexical_environment = &realm().global_environment();
-    execution_context.variable_environment = &global_object.environment();
+    execution_context.variable_environment = &realm().global_environment();
     VERIFY(!vm.exception());
     execution_context.is_strict_mode = program.is_strict_mode();
     vm.push_execution_context(execution_context, global_object);

Userland/Libraries/LibJS/Runtime/AbstractOperations.cpp

@@ -399,7 +399,7 @@ Value perform_eval(Value x, GlobalObject& caller_realm, CallerMode strict_caller
     if (direct == EvalMode::Direct)
         return interpreter.execute_statement(caller_realm, program).value_or(js_undefined());
 
-    TemporaryChange scope_change(vm.running_execution_context().lexical_environment, static_cast<Environment*>(&caller_realm.environment()));
+    TemporaryChange scope_change(vm.running_execution_context().lexical_environment, static_cast<Environment*>(&interpreter.realm().global_environment()));
     TemporaryChange scope_change_strict(vm.running_execution_context().is_strict_mode, strict_caller == CallerMode::Strict);
     return interpreter.execute_statement(caller_realm, program).value_or(js_undefined());
 }

Userland/Libraries/LibJS/Runtime/GlobalObject.cpp

@@ -129,8 +129,6 @@ void GlobalObject::initialize_global_object()
     m_object_prototype = heap().allocate_without_global_object<ObjectPrototype>(*this);
     m_function_prototype = heap().allocate_without_global_object<FunctionPrototype>(*this);
 
-    m_environment = heap().allocate<GlobalEnvironment>(*this, *this, *this);
-
     m_new_object_shape = vm.heap().allocate_without_global_object<Shape>(*this);
     m_new_object_shape->set_prototype_without_transition(m_object_prototype);
 
@@ -293,7 +291,6 @@ void GlobalObject::visit_edges(Visitor& visitor)
     visitor.visit(m_new_ordinary_function_prototype_object_shape);
     visitor.visit(m_proxy_constructor);
     visitor.visit(m_generator_object_prototype);
-    visitor.visit(m_environment);
     visitor.visit(m_array_prototype_values_function);
     visitor.visit(m_eval_function);
     visitor.visit(m_temporal_time_zone_prototype_get_offset_nanoseconds_for_function);

Userland/Libraries/LibJS/Runtime/GlobalObject.h

@@ -21,8 +21,6 @@ public:
 
     virtual ~GlobalObject() override;
 
-    GlobalEnvironment& environment() { return *m_environment; }
-
     Console& console() { return *m_console; }
 
     Shape* empty_object_shape() { return m_empty_object_shape; }
@@ -100,8 +98,6 @@ private:
     // Not included in JS_ENUMERATE_NATIVE_OBJECTS due to missing distinct constructor
     GeneratorObjectPrototype* m_generator_object_prototype { nullptr };
 
-    GlobalEnvironment* m_environment { nullptr };
-
     FunctionObject* m_array_prototype_values_function { nullptr };
     FunctionObject* m_eval_function { nullptr };
     FunctionObject* m_temporal_time_zone_prototype_get_offset_nanoseconds_for_function { nullptr };

Userland/Libraries/LibJS/Runtime/VM.cpp

@@ -413,15 +413,15 @@ Reference VM::get_identifier_reference(Environment* environment, FlyString name,
 
     // FIXME: The remainder of this function is non-conforming.
 
-    auto& global_object = environment->global_object();
     for (; environment && environment->outer_environment(); environment = environment->outer_environment()) {
         auto possible_match = environment->get_from_environment(name);
         if (possible_match.has_value())
             return Reference { *environment, move(name), strict };
     }
 
-    if (global_object.environment().has_binding(name) || !in_strict_mode()) {
+    auto& global_environment = interpreter().realm().global_environment();
-        return Reference { global_object.environment(), move(name), strict };
+    if (global_environment.has_binding(name) || !in_strict_mode()) {
+        return Reference { global_environment, move(name), strict };
     }
 
     return Reference { Reference::BaseType::Unresolvable, move(name), strict };
@@ -646,7 +646,8 @@ void VM::ordinary_call_bind_this(FunctionObject& function, ExecutionContext& cal
     if (function.is_strict_mode()) {
         this_value = this_argument;
     } else if (this_argument.is_nullish()) {
-        auto& global_environment = callee_realm->environment();
+        // FIXME: Make function.realm() an actual Realm, then this will become less horrendous.
+        auto& global_environment = interpreter().realm().global_environment();
         this_value = &global_environment.global_this_value();
     } else {
         this_value = this_argument.to_object(function.global_object());