deimos-lang/dmc-lib/src/ast/function.rs
2026-03-12 21:52:52 -05:00

283 lines
9.2 KiB
Rust

use crate::ast::ir_builder::IrBuilder;
use crate::ast::parameter::Parameter;
use crate::ast::statement::Statement;
use crate::ast::type_use::TypeUse;
use crate::diagnostic::Diagnostic;
use crate::ir::ir_function::IrFunction;
use crate::ir::ir_parameter::IrParameter;
use crate::source_range::SourceRange;
use crate::symbol::Symbol;
use crate::symbol::function_symbol::FunctionSymbol;
use crate::symbol_table::{SymbolInsertError, SymbolTable};
use crate::type_info::TypeInfo;
use std::cell::RefCell;
use std::ops::Neg;
use std::rc::Rc;
pub struct Function {
declared_name: String,
declared_name_source_range: SourceRange,
is_public: bool,
parameters: Vec<Parameter>,
return_type: Option<TypeUse>,
statements: Vec<Statement>,
function_symbol: Option<Rc<RefCell<FunctionSymbol>>>,
}
impl Function {
pub fn new(
declared_name: &str,
declared_name_source_range: SourceRange,
is_public: bool,
parameters: Vec<Parameter>,
return_type: Option<TypeUse>,
statements: Vec<Statement>,
) -> Self {
Self {
declared_name: declared_name.to_string(),
declared_name_source_range,
is_public,
parameters,
return_type,
statements,
function_symbol: None,
}
}
pub fn declared_name(&self) -> &str {
&self.declared_name
}
pub fn statements(&self) -> Vec<&Statement> {
self.statements.iter().collect()
}
pub fn gather_declared_names(
&mut self,
symbol_table: &mut SymbolTable,
) -> Result<(), Vec<Diagnostic>> {
let mut diagnostics = vec![];
if !diagnostics.is_empty() {
return Err(diagnostics);
}
// insert function symbol
let insert_result = symbol_table.insert_function_symbol(FunctionSymbol::new(
self.declared_name(),
self.declared_name_source_range.clone(),
false,
));
// get function symbol if successful
let function_symbol = match insert_result {
Ok(function_symbol) => function_symbol,
Err(symbol_insert_error) => {
return match symbol_insert_error {
SymbolInsertError::AlreadyDeclared(already_declared) => {
diagnostics.push(Diagnostic::new(
&format!(
"Function {} already declared in current scope",
already_declared.symbol().borrow().declared_name()
),
self.declared_name_source_range.start(),
self.declared_name_source_range.end(),
));
Err(diagnostics)
}
};
}
};
// save function symbol for later
self.function_symbol = Some(function_symbol.clone());
// handle parameters
symbol_table.push_function_scope(&format!("function_scope({})", self.declared_name));
let mut parameter_symbols = vec![];
for parameter in &mut self.parameters {
match parameter.gather_declared_names(symbol_table) {
Ok(parameter_symbol) => {
parameter_symbols.push(parameter_symbol);
}
Err(mut parameter_diagnostics) => {
diagnostics.append(&mut parameter_diagnostics);
}
}
}
function_symbol
.borrow_mut()
.set_parameters(parameter_symbols);
// return type
if let Some(type_use) = &mut self.return_type {
match type_use.gather_declared_names(symbol_table) {
Ok(_) => {}
Err(mut type_use_diagnostics) => {
diagnostics.append(&mut type_use_diagnostics);
}
}
}
symbol_table.push_block_scope(&format!("main_block_scope({})", self.declared_name));
for statement in &mut self.statements {
match statement.gather_declared_names(symbol_table) {
Ok(_) => {}
Err(mut statement_diagnostics) => {
diagnostics.append(&mut statement_diagnostics);
}
}
}
symbol_table.pop_scope(); // main block scope
symbol_table.pop_scope(); // function scope
if diagnostics.is_empty() {
Ok(())
} else {
Err(diagnostics)
}
}
pub fn check_name_usages(&mut self, symbol_table: &SymbolTable) -> Result<(), Vec<Diagnostic>> {
let mut diagnostics = vec![];
// parameters
diagnostics.append(
&mut self
.parameters
.iter_mut()
.map(|parameter| parameter.check_name_usages(symbol_table))
.filter_map(|result| result.err())
.flatten()
.collect(),
);
// return type
if let Some(type_use) = &mut self.return_type {
match type_use.check_name_usages(symbol_table) {
Ok(_) => {
// set return type info on function symbol
self.function_symbol
.as_mut()
.unwrap()
.borrow_mut()
.set_return_type_info(type_use.to_type_info());
}
Err(mut type_use_diagnostics) => {
diagnostics.append(&mut type_use_diagnostics);
}
}
} else {
// we don't have a given return type, so it's void
self.function_symbol
.as_mut()
.unwrap()
.borrow_mut()
.set_return_type_info(TypeInfo::Void);
}
// statements
for statement in &mut self.statements {
match statement.check_name_usages(symbol_table) {
Ok(_) => {}
Err(mut statement_diagnostics) => {
diagnostics.append(&mut statement_diagnostics);
}
}
}
if diagnostics.is_empty() {
Ok(())
} else {
Err(diagnostics)
}
}
pub fn type_check(&mut self, symbol_table: &SymbolTable) -> Result<(), Vec<Diagnostic>> {
let mut diagnostics = vec![];
// parameters
diagnostics.append(
&mut self
.parameters
.iter_mut()
.map(|parameter| parameter.type_check(symbol_table))
.filter_map(Result::err)
.flatten()
.collect(),
);
let function_symbol = self.function_symbol.as_ref().unwrap();
let return_type_info = function_symbol.borrow().return_type_info().clone();
let statements_len = self.statements.len();
// statements
diagnostics.append(
&mut self
.statements
.iter_mut()
.enumerate()
.map(|(i, statement)| {
let is_last = i == statements_len - 1;
if is_last {
statement.type_check(symbol_table, Some(&return_type_info))
} else {
statement.type_check(symbol_table, None)
}
})
.filter_map(Result::err)
.flatten()
.collect(),
);
if diagnostics.is_empty() {
Ok(())
} else {
Err(diagnostics)
}
}
pub fn to_ir(&self, symbol_table: &SymbolTable) -> IrFunction {
let mut builder = IrBuilder::new();
// parameters
for (i, parameter) in self.parameters.iter().enumerate() {
let parameter_symbol = parameter.parameter_symbol();
let stack_offset = (self.parameters.len() as isize).neg() + (i as isize);
let ir_parameter = IrParameter::new(
parameter_symbol.borrow().declared_name(),
parameter_symbol.borrow().type_info().clone(),
stack_offset,
);
let as_rc = Rc::new(ir_parameter);
builder.parameters_mut().push(as_rc.clone());
parameter_symbol.borrow_mut().set_ir_parameter(as_rc);
}
let entry_block_id = builder.new_block();
let function_symbol = self.function_symbol.as_ref().unwrap().borrow();
let return_type_info = function_symbol.return_type_info();
let should_return_value = !matches!(return_type_info, TypeInfo::Void);
for (i, statement) in self.statements.iter().enumerate() {
let is_last = i == self.statements.len() - 1;
statement.to_ir(&mut builder, symbol_table, should_return_value && is_last);
}
builder.finish_block();
let entry_block = builder.get_block(entry_block_id).clone();
IrFunction::new(
self.function_symbol
.as_ref()
.unwrap()
.borrow()
.declared_name_owned(), // ok for now... but we need to start using the fqn
builder.parameters(),
return_type_info,
entry_block,
)
}
}