optimize/src/visitor/constant_folder.rs
2021-05-19 18:34:26 +07:00

120 lines
3.6 KiB
Rust

mod expression_reducer;
mod scope;
use full_moon::ast::*;
use crate::visitor::Visitor;
pub struct ConstantFolder {
scope: scope::Scope,
}
impl ConstantFolder {
pub fn new() -> Self {
ConstantFolder {
scope: scope::Scope::new(),
}
}
fn register_local(&mut self, name: String, value: Option<Expression>) {
let var = expression_reducer::Variable::with_value(name, value, &self.scope);
self.scope.push_var(var);
}
fn assign(&mut self, name: String, value: Option<Expression>) {
let var = expression_reducer::Variable::with_value(name, value, &self.scope);
self.scope.set_var(var);
}
}
impl Visitor for ConstantFolder {
fn visit_assignment<'a>(&mut self, assignment: &Assignment<'a>) {
let mut names = assignment.variables().iter();
let mut expressions = assignment.expressions().iter();
loop {
let name = names.next().map(|x| match x {
Var::Expression(_var_expr) => {
panic!("assignment Var::Expression is not supported")
}
Var::Name(n) => n.token().to_string(),
_ => unreachable!(),
});
let expr = expressions.next().map(|x| x.clone() /* reduced */);
match name {
Some(name) => {
self.assign(name, expr);
}
None => {
break;
}
}
}
}
fn visit_do<'a>(&mut self, do_: &Do<'a>) {
println!("visit do {}", do_);
}
fn visit_function_call<'a>(&mut self, function_call: &FunctionCall<'a>) {
println!("visit function_call {}", function_call);
let reduced = expression_reducer::reduce_expression_value_function_call(
function_call.clone(),
&self.scope,
);
println!("{:?}", reduced);
}
fn visit_function_declaration<'a>(&mut self, function_declaration: &FunctionDeclaration<'a>) {
println!("visit function_declaration {}", function_declaration);
}
fn visit_generic_for<'a>(&mut self, generic_for: &GenericFor<'a>) {
println!("visit generic_for {}", generic_for);
}
fn visit_if<'a>(&mut self, if_: &If<'a>) {
println!("visit if {}", if_);
}
fn visit_local_assignment<'a>(&mut self, local_assignment: &LocalAssignment<'a>) {
let mut names = local_assignment.names().iter();
let mut expressions = local_assignment.expressions().iter();
loop {
let name = names.next().map(|x| x.token().to_string());
let expr = expressions.next().map(|x| x.clone() /* reduced */);
match name {
Some(name) => {
self.register_local(name, expr);
}
None => {
break;
}
}
}
}
fn visit_local_function<'a>(&mut self, local_function: &LocalFunction<'a>) {
println!("visit local_function {}", local_function);
}
fn visit_numeric_for<'a>(&mut self, numeric_for: &NumericFor<'a>) {
println!("visit numeric_for {}", numeric_for);
}
fn visit_repeat<'a>(&mut self, repeat: &Repeat<'a>) {
println!("visit repeat {}", repeat);
}
fn visit_while<'a>(&mut self, while_: &While<'a>) {
println!("visit while {}", while_);
}
fn visit_goto<'a>(&mut self, goto: &lua52::Goto<'a>) {
println!("visit goto {}", goto);
}
fn visit_label<'a>(&mut self, label: &lua52::Label<'a>) {
println!("visit label {}", label);
}
}