mirror of
https://github.com/RGBCube/serenity
synced 2025-05-20 14:25:08 +00:00
LibJS: Generate bytecode in basic blocks instead of one big block
This limits the size of each block (currently set to 1K), and gets us
closer to a canonical, more easily analysable bytecode format.
As a result of this, "Labels" are now simply entries to basic blocks.
Since there is no more 'conditional' jump (as all jumps are always
taken), JumpIf{True,False} are unified to JumpConditional, and
JumpIfNullish is renamed to JumpNullish.
Also fixes #7914 as a result of reimplementing the loop logic.
This commit is contained in:
Ali Mohammad Pur
Andreas Kling
parent
d7a25cdb82
commit
01e8f0889a
16 changed files with 392 additions and 174 deletions
|
|
@ -119,23 +119,43 @@ void LogicalExpression::generate_bytecode(Bytecode::Generator& generator) const
|
|||
{
|
||||
m_lhs->generate_bytecode(generator);
|
||||
|
||||
Bytecode::Op::Jump* test_instr;
|
||||
// lhs
|
||||
// jump op (true) end (false) rhs
|
||||
// rhs
|
||||
// jump always (true) end
|
||||
// end
|
||||
|
||||
auto& rhs_block = generator.make_block();
|
||||
auto& end_block = generator.make_block();
|
||||
|
||||
switch (m_op) {
|
||||
case LogicalOp::And:
|
||||
test_instr = &generator.emit<Bytecode::Op::JumpIfFalse>();
|
||||
generator.emit<Bytecode::Op::JumpConditional>().set_targets(
|
||||
Bytecode::Label { rhs_block },
|
||||
Bytecode::Label { end_block });
|
||||
break;
|
||||
case LogicalOp::Or:
|
||||
test_instr = &generator.emit<Bytecode::Op::JumpIfTrue>();
|
||||
generator.emit<Bytecode::Op::JumpConditional>().set_targets(
|
||||
Bytecode::Label { end_block },
|
||||
Bytecode::Label { rhs_block });
|
||||
break;
|
||||
case LogicalOp::NullishCoalescing:
|
||||
test_instr = &generator.emit<Bytecode::Op::JumpIfNotNullish>();
|
||||
generator.emit<Bytecode::Op::JumpNullish>().set_targets(
|
||||
Bytecode::Label { rhs_block },
|
||||
Bytecode::Label { end_block });
|
||||
break;
|
||||
default:
|
||||
VERIFY_NOT_REACHED();
|
||||
}
|
||||
|
||||
generator.switch_to_basic_block(rhs_block);
|
||||
m_rhs->generate_bytecode(generator);
|
||||
test_instr->set_target(generator.make_label());
|
||||
|
||||
generator.emit<Bytecode::Op::Jump>().set_targets(
|
||||
Bytecode::Label { end_block },
|
||||
{});
|
||||
|
||||
generator.switch_to_basic_block(end_block);
|
||||
}
|
||||
|
||||
void UnaryExpression::generate_bytecode(Bytecode::Generator& generator) const
|
||||
|
|
@ -279,58 +299,154 @@ void AssignmentExpression::generate_bytecode(Bytecode::Generator& generator) con
|
|||
|
||||
void WhileStatement::generate_bytecode(Bytecode::Generator& generator) const
|
||||
{
|
||||
// test
|
||||
// jump if_false (true) end (false) body
|
||||
// body
|
||||
// jump always (true) test
|
||||
// end
|
||||
auto& test_block = generator.make_block();
|
||||
auto& body_block = generator.make_block();
|
||||
auto& end_block = generator.make_block();
|
||||
|
||||
// Init result register
|
||||
generator.emit<Bytecode::Op::LoadImmediate>(js_undefined());
|
||||
generator.begin_continuable_scope();
|
||||
auto test_label = generator.make_label();
|
||||
auto result_reg = generator.allocate_register();
|
||||
generator.emit<Bytecode::Op::Store>(result_reg);
|
||||
|
||||
// jump to the test block
|
||||
generator.emit<Bytecode::Op::Jump>().set_targets(
|
||||
Bytecode::Label { test_block },
|
||||
{});
|
||||
|
||||
generator.switch_to_basic_block(test_block);
|
||||
m_test->generate_bytecode(generator);
|
||||
auto& test_jump = generator.emit<Bytecode::Op::JumpIfFalse>();
|
||||
generator.emit<Bytecode::Op::JumpConditional>().set_targets(
|
||||
Bytecode::Label { body_block },
|
||||
Bytecode::Label { end_block });
|
||||
|
||||
generator.switch_to_basic_block(body_block);
|
||||
generator.begin_continuable_scope(Bytecode::Label { test_block });
|
||||
m_body->generate_bytecode(generator);
|
||||
generator.emit<Bytecode::Op::Jump>(test_label);
|
||||
test_jump.set_target(generator.make_label());
|
||||
generator.emit<Bytecode::Op::Jump>().set_targets(
|
||||
Bytecode::Label { test_block },
|
||||
{});
|
||||
generator.end_continuable_scope();
|
||||
|
||||
generator.switch_to_basic_block(end_block);
|
||||
generator.emit<Bytecode::Op::Load>(result_reg);
|
||||
}
|
||||
|
||||
void DoWhileStatement::generate_bytecode(Bytecode::Generator& generator) const
|
||||
{
|
||||
// jump always (true) body
|
||||
// test
|
||||
// jump if_false (true) end (false) body
|
||||
// body
|
||||
// jump always (true) test
|
||||
// end
|
||||
auto& test_block = generator.make_block();
|
||||
auto& body_block = generator.make_block();
|
||||
auto& end_block = generator.make_block();
|
||||
|
||||
// Init result register
|
||||
generator.emit<Bytecode::Op::LoadImmediate>(js_undefined());
|
||||
generator.begin_continuable_scope();
|
||||
auto head_label = generator.make_label();
|
||||
m_body->generate_bytecode(generator);
|
||||
generator.end_continuable_scope();
|
||||
auto result_reg = generator.allocate_register();
|
||||
generator.emit<Bytecode::Op::Store>(result_reg);
|
||||
|
||||
// jump to the body block
|
||||
generator.emit<Bytecode::Op::Jump>().set_targets(
|
||||
Bytecode::Label { body_block },
|
||||
{});
|
||||
|
||||
generator.switch_to_basic_block(test_block);
|
||||
m_test->generate_bytecode(generator);
|
||||
generator.emit<Bytecode::Op::JumpIfTrue>(head_label);
|
||||
generator.emit<Bytecode::Op::JumpConditional>().set_targets(
|
||||
Bytecode::Label { body_block },
|
||||
Bytecode::Label { end_block });
|
||||
|
||||
generator.switch_to_basic_block(body_block);
|
||||
generator.begin_continuable_scope(Bytecode::Label { test_block });
|
||||
m_body->generate_bytecode(generator);
|
||||
generator.emit<Bytecode::Op::Jump>().set_targets(
|
||||
Bytecode::Label { test_block },
|
||||
{});
|
||||
generator.end_continuable_scope();
|
||||
|
||||
generator.switch_to_basic_block(end_block);
|
||||
generator.emit<Bytecode::Op::Load>(result_reg);
|
||||
}
|
||||
|
||||
void ForStatement::generate_bytecode(Bytecode::Generator& generator) const
|
||||
{
|
||||
Bytecode::Op::Jump* test_jump { nullptr };
|
||||
// init
|
||||
// jump always (true) test
|
||||
// test
|
||||
// jump if_true (true) body (false) end
|
||||
// body
|
||||
// jump always (true) update
|
||||
// update
|
||||
// jump always (true) test
|
||||
// end
|
||||
|
||||
// If 'test' is missing, fuse the 'test' and 'body' basic blocks
|
||||
// If 'update' is missing, fuse the 'body' and 'update' basic blocks
|
||||
|
||||
Bytecode::BasicBlock* test_block_ptr { nullptr };
|
||||
Bytecode::BasicBlock* body_block_ptr { nullptr };
|
||||
Bytecode::BasicBlock* update_block_ptr { nullptr };
|
||||
|
||||
auto& end_block = generator.make_block();
|
||||
|
||||
if (m_init)
|
||||
m_init->generate_bytecode(generator);
|
||||
|
||||
body_block_ptr = &generator.make_block();
|
||||
|
||||
if (m_test)
|
||||
test_block_ptr = &generator.make_block();
|
||||
else
|
||||
test_block_ptr = body_block_ptr;
|
||||
|
||||
if (m_update)
|
||||
update_block_ptr = &generator.make_block();
|
||||
else
|
||||
update_block_ptr = body_block_ptr;
|
||||
|
||||
generator.emit<Bytecode::Op::LoadImmediate>(js_undefined());
|
||||
generator.begin_continuable_scope();
|
||||
auto jump_label = generator.make_label();
|
||||
auto result_reg = generator.allocate_register();
|
||||
generator.emit<Bytecode::Op::Store>(result_reg);
|
||||
|
||||
generator.emit<Bytecode::Op::Jump>().set_targets(
|
||||
Bytecode::Label { *test_block_ptr },
|
||||
{});
|
||||
|
||||
if (m_test) {
|
||||
generator.switch_to_basic_block(*test_block_ptr);
|
||||
m_test->generate_bytecode(generator);
|
||||
test_jump = &generator.emit<Bytecode::Op::JumpIfFalse>();
|
||||
generator.emit<Bytecode::Op::JumpConditional>().set_targets(
|
||||
Bytecode::Label { *body_block_ptr },
|
||||
Bytecode::Label { end_block });
|
||||
}
|
||||
|
||||
generator.switch_to_basic_block(*body_block_ptr);
|
||||
generator.begin_continuable_scope(Bytecode::Label { *update_block_ptr });
|
||||
m_body->generate_bytecode(generator);
|
||||
if (m_update)
|
||||
m_update->generate_bytecode(generator);
|
||||
generator.emit<Bytecode::Op::Jump>(jump_label);
|
||||
if (m_test)
|
||||
test_jump->set_target(generator.make_label());
|
||||
generator.end_continuable_scope();
|
||||
|
||||
if (m_update) {
|
||||
generator.emit<Bytecode::Op::Jump>().set_targets(
|
||||
Bytecode::Label { *update_block_ptr },
|
||||
{});
|
||||
|
||||
generator.switch_to_basic_block(*update_block_ptr);
|
||||
m_update->generate_bytecode(generator);
|
||||
}
|
||||
|
||||
generator.emit<Bytecode::Op::Jump>().set_targets(
|
||||
Bytecode::Label { *test_block_ptr },
|
||||
{});
|
||||
|
||||
generator.switch_to_basic_block(end_block);
|
||||
generator.emit<Bytecode::Op::Load>(result_reg);
|
||||
}
|
||||
|
||||
|
|
@ -408,23 +524,60 @@ void ReturnStatement::generate_bytecode(Bytecode::Generator& generator) const
|
|||
|
||||
void IfStatement::generate_bytecode(Bytecode::Generator& generator) const
|
||||
{
|
||||
m_predicate->generate_bytecode(generator);
|
||||
auto& else_jump = generator.emit<Bytecode::Op::JumpIfFalse>();
|
||||
// test
|
||||
// jump if_true (true) true (false) false
|
||||
// true
|
||||
// jump always (true) end
|
||||
// false
|
||||
// jump always (true) end
|
||||
// end
|
||||
|
||||
// If the 'false' branch doesn't exist, we're just gonna substitute it for 'end' and elide the last two entries above.
|
||||
|
||||
auto& true_block = generator.make_block();
|
||||
auto& false_block = generator.make_block();
|
||||
|
||||
m_predicate->generate_bytecode(generator);
|
||||
generator.emit<Bytecode::Op::JumpConditional>().set_targets(
|
||||
Bytecode::Label { true_block },
|
||||
Bytecode::Label { false_block });
|
||||
|
||||
Bytecode::Op::Jump* true_block_jump { nullptr };
|
||||
|
||||
generator.switch_to_basic_block(true_block);
|
||||
m_consequent->generate_bytecode(generator);
|
||||
if (!generator.is_current_block_terminated())
|
||||
true_block_jump = &generator.emit<Bytecode::Op::Jump>();
|
||||
|
||||
generator.switch_to_basic_block(false_block);
|
||||
if (m_alternate) {
|
||||
auto& if_jump = generator.emit<Bytecode::Op::Jump>();
|
||||
else_jump.set_target(generator.make_label());
|
||||
auto& end_block = generator.make_block();
|
||||
|
||||
m_alternate->generate_bytecode(generator);
|
||||
if_jump.set_target(generator.make_label());
|
||||
if (!generator.is_current_block_terminated())
|
||||
generator.emit<Bytecode::Op::Jump>().set_targets(
|
||||
Bytecode::Label { end_block },
|
||||
{});
|
||||
|
||||
if (true_block_jump)
|
||||
true_block_jump->set_targets(
|
||||
Bytecode::Label { end_block },
|
||||
{});
|
||||
|
||||
generator.switch_to_basic_block(end_block);
|
||||
} else {
|
||||
else_jump.set_target(generator.make_label());
|
||||
if (true_block_jump)
|
||||
true_block_jump->set_targets(
|
||||
Bytecode::Label { false_block },
|
||||
{});
|
||||
}
|
||||
}
|
||||
|
||||
void ContinueStatement::generate_bytecode(Bytecode::Generator& generator) const
|
||||
{
|
||||
generator.emit<Bytecode::Op::Jump>(generator.nearest_continuable_scope());
|
||||
generator.emit<Bytecode::Op::Jump>().set_targets(
|
||||
generator.nearest_continuable_scope(),
|
||||
{});
|
||||
}
|
||||
|
||||
void DebuggerStatement::generate_bytecode(Bytecode::Generator&) const
|
||||
|
|
@ -433,16 +586,36 @@ void DebuggerStatement::generate_bytecode(Bytecode::Generator&) const
|
|||
|
||||
void ConditionalExpression::generate_bytecode(Bytecode::Generator& generator) const
|
||||
{
|
||||
// test
|
||||
// jump if_true (true) true (false) false
|
||||
// true
|
||||
// jump always (true) end
|
||||
// false
|
||||
// jump always (true) end
|
||||
// end
|
||||
|
||||
auto& true_block = generator.make_block();
|
||||
auto& false_block = generator.make_block();
|
||||
auto& end_block = generator.make_block();
|
||||
|
||||
m_test->generate_bytecode(generator);
|
||||
auto& alternate_jump = generator.emit<Bytecode::Op::JumpIfFalse>();
|
||||
generator.emit<Bytecode::Op::JumpConditional>().set_targets(
|
||||
Bytecode::Label { true_block },
|
||||
Bytecode::Label { false_block });
|
||||
|
||||
generator.switch_to_basic_block(true_block);
|
||||
m_consequent->generate_bytecode(generator);
|
||||
auto& end_jump = generator.emit<Bytecode::Op::Jump>();
|
||||
generator.emit<Bytecode::Op::Jump>().set_targets(
|
||||
Bytecode::Label { end_block },
|
||||
{});
|
||||
|
||||
alternate_jump.set_target(generator.make_label());
|
||||
generator.switch_to_basic_block(false_block);
|
||||
m_alternate->generate_bytecode(generator);
|
||||
generator.emit<Bytecode::Op::Jump>().set_targets(
|
||||
Bytecode::Label { end_block },
|
||||
{});
|
||||
|
||||
end_jump.set_target(generator.make_label());
|
||||
generator.switch_to_basic_block(end_block);
|
||||
}
|
||||
|
||||
void SequenceExpression::generate_bytecode(Bytecode::Generator& generator) const
|
||||
|
|
@ -464,5 +637,4 @@ void TemplateLiteral::generate_bytecode(Bytecode::Generator& generator) const
|
|||
}
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue