RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-05-28 16:25:06 +00:00
Code Issues Activity Actions

LibJS/Bytecode: Cache object own property accesses

Browse source 
The instructions GetById and GetByIdWithThis now remember the last-seen
Shape, and if we see the same object again, we reuse the property offset
from last time without doing a new lookup.

This allows us to use Object::get_direct(), bypassing the entire lookup
machinery and saving lots of time.

~23% speed-up on Kraken/ai-astar.js :^)
This commit is contained in:
Andreas Kling 2023-07-08 17:43:26 +02:00
parent 52cd671163
commit de8e4b1853
8 changed files with 76 additions and 26 deletions
Download patch file Download diff file Expand all files Collapse all files

18
Userland/Libraries/LibJS/Bytecode/Generator.cpp
View file

@ -54,8 +54,12 @@ CodeGenerationErrorOr<NonnullOwnPtr<Executable>> Generator::generate(ASTNode con
else if (is<FunctionExpression>(node))
is_strict_mode = static_cast<FunctionExpression const&>(node).is_strict_mode();
Vector<PropertyLookupCache> property_lookup_caches;
property_lookup_caches.resize(generator.m_next_property_lookup_cache);
return adopt_own(*new Executable {
.name = {},
.property_lookup_caches = move(property_lookup_caches),
.basic_blocks = move(generator.m_root_basic_blocks),
.string_table = move(generator.m_string_table),
.identifier_table = move(generator.m_identifier_table),
@ -199,7 +203,7 @@ CodeGenerationErrorOr<void> Generator::emit_load_from_reference(JS::ASTNode cons
} else {
// 3. Let propertyKey be StringValue of IdentifierName.
auto identifier_table_ref = intern_identifier(verify_cast<Identifier>(expression.property()).string());
emit<Bytecode::Op::GetByIdWithThis>(identifier_table_ref, super_reference.this_value);
emit_get_by_id_with_this(identifier_table_ref, super_reference.this_value);
}
} else {
TRY(expression.object().generate_bytecode(*this));
@ -212,7 +216,7 @@ CodeGenerationErrorOr<void> Generator::emit_load_from_reference(JS::ASTNode cons
emit<Bytecode::Op::GetByValue>(object_reg);
} else if (expression.property().is_identifier()) {
auto identifier_table_ref = intern_identifier(verify_cast<Identifier>(expression.property()).string());
emit<Bytecode::Op::GetById>(identifier_table_ref);
emit_get_by_id(identifier_table_ref);
} else if (expression.property().is_private_identifier()) {
auto identifier_table_ref = intern_identifier(verify_cast<PrivateIdentifier>(expression.property()).string());
emit<Bytecode::Op::GetPrivateById>(identifier_table_ref);
@ -543,4 +547,14 @@ CodeGenerationErrorOr<void> Generator::emit_named_evaluation_if_anonymous_functi
return {};
}
void Generator::emit_get_by_id(IdentifierTableIndex id)
{
emit<Op::GetById>(id, m_next_property_lookup_cache++);
}
void Generator::emit_get_by_id_with_this(IdentifierTableIndex id, Register this_reg)
{
emit<Op::GetByIdWithThis>(id, this_reg, m_next_property_lookup_cache++);
}
}