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LibJS: Don't add uncaptured parameter bindings to environment

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For parameters that exist strictly as "locals", we can save time and
space by not adding them to the function environment.

This is a speed-up across the board on basically every test.
For example, ~11% on Octane/typescript.js :^)
This commit is contained in:
Andreas Kling 2024-01-21 16:06:18 +01:00
parent 7e2308d290
commit bed78eb3cc
Notes: sideshowbarker 2024-07-17 05:13:53 +09:00
2 changed files with 19 additions and 11 deletions
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24
Userland/Libraries/LibJS/Runtime/ECMAScriptFunctionObject.cpp
View file

@ -125,7 +125,7 @@ ECMAScriptFunctionObject::ECMAScriptFunctionObject(DeprecatedFlyString name, Byt
parameter.binding.visit(
[&](Identifier const& identifier) {
if (m_parameter_names.set(identifier.string()) != AK::HashSetResult::InsertedNewEntry)
if (m_parameter_names.set(identifier.string(), identifier.is_local() ? ParameterIsLocal::Yes : ParameterIsLocal::No) != AK::HashSetResult::InsertedNewEntry)
m_has_duplicates = true;
},
[&](NonnullRefPtr<BindingPattern const> const& pattern) {
@ -134,7 +134,7 @@ ECMAScriptFunctionObject::ECMAScriptFunctionObject(DeprecatedFlyString name, Byt
// NOTE: Nothing in the callback throws an exception.
MUST(pattern->for_each_bound_identifier([&](auto& identifier) {
if (m_parameter_names.set(identifier.string()) != AK::HashSetResult::InsertedNewEntry)
if (m_parameter_names.set(identifier.string(), identifier.is_local() ? ParameterIsLocal::Yes : ParameterIsLocal::No) != AK::HashSetResult::InsertedNewEntry)
m_has_duplicates = true;
}));
});
@ -204,13 +204,13 @@ ECMAScriptFunctionObject::ECMAScriptFunctionObject(DeprecatedFlyString name, Byt
*environment_size += m_parameter_names.size();
HashTable<DeprecatedFlyString> parameter_bindings;
HashMap<DeprecatedFlyString, ParameterIsLocal> parameter_bindings;
// 22. If argumentsObjectNeeded is true, then
if (m_arguments_object_needed) {
// f. Let parameterBindings be the list-concatenation of parameterNames and « "arguments" ».
parameter_bindings = m_parameter_names;
parameter_bindings.set(vm().names.arguments.as_string());
parameter_bindings.set(vm().names.arguments.as_string(), ParameterIsLocal::No);
(*environment_size)++;
} else {
@ -218,7 +218,7 @@ ECMAScriptFunctionObject::ECMAScriptFunctionObject(DeprecatedFlyString name, Byt
// a. Let parameterBindings be parameterNames.
}
HashTable<DeprecatedFlyString> instantiated_var_names;
HashMap<DeprecatedFlyString, ParameterIsLocal> instantiated_var_names;
size_t* var_environment_size = nullptr;
@ -231,7 +231,7 @@ ECMAScriptFunctionObject::ECMAScriptFunctionObject(DeprecatedFlyString name, Byt
// c. For each element n of varNames, do
MUST(scope_body->for_each_var_declared_identifier([&](auto const& id) {
// i. If instantiatedVarNames does not contain n, then
if (instantiated_var_names.set(id.string()) == AK::HashSetResult::InsertedNewEntry) {
if (instantiated_var_names.set(id.string(), id.is_local() ? ParameterIsLocal::Yes : ParameterIsLocal::No) == AK::HashSetResult::InsertedNewEntry) {
// 1. Append n to instantiatedVarNames.
// Following steps will be executed in function_declaration_instantiation:
// 2. Perform ! env.CreateMutableBinding(n, false).
@ -266,7 +266,7 @@ ECMAScriptFunctionObject::ECMAScriptFunctionObject(DeprecatedFlyString name, Byt
// Following steps will be executed in function_declaration_instantiation:
// 2. Perform ! env.CreateMutableBinding(n, false).
// 3. Perform ! env.InitializeBinding(n, undefined).
if (instantiated_var_names.set(id.string()) == AK::HashSetResult::InsertedNewEntry) {
if (instantiated_var_names.set(id.string(), id.is_local() ? ParameterIsLocal::Yes : ParameterIsLocal::No) == AK::HashSetResult::InsertedNewEntry) {
m_var_names_to_initialize_binding.append({
.identifier = id,
.parameter_binding = parameter_bindings.contains(id.string()),
@ -290,7 +290,7 @@ ECMAScriptFunctionObject::ECMAScriptFunctionObject(DeprecatedFlyString name, Byt
if (!instantiated_var_names.contains(function_name) && function_name != vm().names.arguments.as_string()) {
m_function_names_to_initialize_binding.append(function_name);
instantiated_var_names.set(function_name);
instantiated_var_names.set(function_name, ParameterIsLocal::No);
(*var_environment_size)++;
}
@ -620,6 +620,10 @@ ThrowCompletionOr<void> ECMAScriptFunctionObject::function_declaration_instantia
// 21. For each String paramName of parameterNames, do
for (auto const& parameter_name : m_parameter_names) {
// OPTIMIZATION: Parameters that are locals don't need to be added to the environment.
if (parameter_name.value == ParameterIsLocal::Yes)
continue;
// a. Let alreadyDeclared be ! env.HasBinding(paramName).
// b. NOTE: Early errors ensure that duplicate parameter names can only occur in non-strict functions that do not have parameter default values or rest parameters.
@ -627,12 +631,12 @@ ThrowCompletionOr<void> ECMAScriptFunctionObject::function_declaration_instantia
// c. If alreadyDeclared is false, then
// NOTE: alreadyDeclared is always false because we use hash table for parameterNames
// i. Perform ! env.CreateMutableBinding(paramName, false).
MUST(environment->create_mutable_binding(vm, parameter_name, false));
MUST(environment->create_mutable_binding(vm, parameter_name.key, false));
// ii. If hasDuplicates is true, then
if (m_has_duplicates) {
// 1. Perform ! env.InitializeBinding(paramName, undefined).
MUST(environment->initialize_binding(vm, parameter_name, js_undefined(), Environment::InitializeBindingHint::Normal));
MUST(environment->initialize_binding(vm, parameter_name.key, js_undefined(), Environment::InitializeBindingHint::Normal));
}
}

6
Userland/Libraries/LibJS/Runtime/ECMAScriptFunctionObject.h
View file

@ -153,7 +153,11 @@ private:
bool m_has_parameter_expressions { false };
bool m_has_duplicates { false };
HashTable<DeprecatedFlyString> m_parameter_names;
enum class ParameterIsLocal {
No,
Yes,
};
HashMap<DeprecatedFlyString, ParameterIsLocal> m_parameter_names;
Vector<FunctionDeclaration const&> m_functions_to_initialize;
bool m_arguments_object_needed { false };
bool m_is_module_wrapper { false };