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typing.rs
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typing.rs
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use ahash::AHashMap;
use crate::ast::parse_ast as untyp;
use crate::ast::typed_ast as typ;
use std::convert::TryFrom;
use untyp::Pos;
/*
This file aims to type the program.
This is mostly veryfying all operations are between expressions of the right size, and attributing a bus size
to every expression.
It also transforms the ast in a typed_ast, which is a lot simpler and without location information.
Scoping is also done in this file. It just means shared variables are particularized.
The compiler / interpreter must fail as little as possible after this point (as there are no more localisation info)
*/
#[derive(Debug)]
pub enum TypingError {
NegativeSizeBus(Pos, i32),
MismatchedBusSize(Token, Token), //expected X, got X
UnknownVar(String, Pos),
DuplicateVar(String, Pos, Pos),
UnknownState(String, Pos),
ExpectedSizeOne(Pos, usize),
IndexOutOfRange(Pos, i32, usize),
LocalVarInUnless(Pos, String), //unless is not fully implemented
NonSharedInLast(Pos, String),
ConflictingStateShared(Pos, String, Pos), //shared variables and states cannot have conflicting names
}
#[derive(Debug)]
pub struct Token {
pub loc: Pos,
pub name: Option<String>,
pub length: usize,
}
type Result<T> = std::result::Result<T, TypingError>;
//the main wrapper function
pub fn type_prog(
mut prog: untyp::Program,
mut type_constraints: AHashMap<String, (i32, Pos)>,
) -> Result<typ::Program> {
let mut shared_types: AHashMap<String, (usize, Pos)> = AHashMap::new();
let main_module = prog.automata.get_mut("main").unwrap();
//build the map of shared variables, and type them as well.
let mut shared_map = main_module
.shared
.drain(..)
.map(|untyp::VarAssign { var, expr }| {
let loc = expr.loc;
if let untyp::Expr::Const(c) = expr.value {
let v = match c {
untyp::ConstExpr::Known(vec) => vec,
untyp::ConstExpr::Unknown(b, c) => {
if let untyp::Const::Value(i) = c.value {
//try i into usize, if it fails then i is negative and an error is thrown
let j = usize::try_from(i)
.map_err(|_| TypingError::NegativeSizeBus(c.loc, i))?;
vec![b; j]
} else {
panic!("Should not happen : unknown const in typing");
}
}
};
if let Some((_, other_loc)) = shared_types.get(&var.value) {
return Err(TypingError::DuplicateVar(
var.value.clone(),
loc,
*other_loc,
));
}
shared_types.insert(var.value.clone(), (v.len(), loc));
Ok((var.value, v))
} else {
panic!("Should not happen : non-value constant encountered while typing")
}
})
.collect::<Result<AHashMap<String, Vec<bool>>>>()?;
//States name are shared variable which indicated the state of the state (running or not)
for (name, state) in main_module.states.iter() {
if shared_map.contains_key(name) {
let (_, loc) = shared_types.get(name).unwrap();
return Err(TypingError::ConflictingStateShared(
state.name.loc,
state.name.value.clone(),
*loc,
));
}
shared_types.insert(name.clone(), (1, state.name.loc));
}
//inputs are added as shared variables.
//the types are also added in a vector for module typing.
let mut in_types = Vec::new();
let inputs = main_module
.inputs
.drain(..)
.map(|arg| {
let loc = arg.size.loc;
if let untyp::Const::Value(i) = arg.size.value {
let j = usize::try_from(i).map_err(|_| TypingError::NegativeSizeBus(loc, i))?;
in_types.push((j, loc));
if let Some((_, other_loc)) = shared_types.get(&arg.name) {
return Err(TypingError::DuplicateVar(arg.name.clone(), loc, *other_loc));
}
shared_types.insert(arg.name.clone(), (j, loc));
Ok(typ::Sized {
value: arg.name,
size: j,
})
} else {
panic!("Should not happen : unknown const in typing");
}
})
.collect::<Result<Vec<typ::Sized<String>>>>()?;
//outputs can be shared variables or inputs.
//the types are also added in a vector for use in external module typing.
let mut out_types = Vec::new();
let outputs = main_module
.outputs
.drain(..)
.map(|arg| {
let loc = arg.size.loc;
if let untyp::Const::Value(i) = arg.size.value {
let j = usize::try_from(i).map_err(|_| TypingError::NegativeSizeBus(loc, i))?;
out_types.push((j, loc));
if let Some((i_decl, loc_decl)) = shared_types.get(&arg.name) {
if *i_decl != j {
let token1 = Token {
loc: *loc_decl,
name: Some(format_var(arg.name.clone())),
length: *i_decl,
};
let token2 = Token {
loc,
name: Some(format_var(arg.name.clone())),
length: j,
};
Err(TypingError::MismatchedBusSize(token1, token2))
} else {
Ok(typ::Sized {
value: arg.name,
size: j,
})
}
} else {
shared_map.insert(arg.name.clone(), vec![false; j]);
shared_types.insert(arg.name.clone(), (j, loc));
Ok(typ::Sized {
value: arg.name,
size: j,
})
}
} else {
panic!("Should not happen : unknown const in typing");
}
})
.collect::<Result<Vec<typ::Sized<String>>>>()?;
let states_map = main_module
.states
.iter()
.map(|(_, state)| (state.name.to_string(), state.name.loc))
.collect::<AHashMap<String, Pos>>();
//If init states were specified, use them. Else, use the first state.
let init_states = main_module
.init_states
.drain(..)
.map(|s| {
if states_map.contains_key(&s.value) {
Ok(s.value)
} else {
Err(TypingError::UnknownState(s.value, s.loc))
}
})
.collect::<Result<Vec<String>>>()?;
let states = main_module
.states
.drain()
.map(|(_, state)| {
Ok((
state.name.value.clone(),
type_state(state, &states_map, &shared_types, &mut type_constraints)?,
))
})
.collect::<Result<AHashMap<typ::Name, typ::State>>>()?;
Ok(typ::Program {
inputs,
outputs,
states,
shared: shared_map,
init_states,
})
}
//type a state. It has to type all the statements and transitions
fn type_state(
mut state: untyp::State,
states_map: &AHashMap<String, Pos>,
shared_types: &AHashMap<String, (usize, Pos)>,
type_constraints: &mut AHashMap<String, (i32, Pos)>,
) -> Result<typ::State> {
let mut var_types: AHashMap<String, (usize, Pos)> = AHashMap::new();
let statements = state
.statements
.drain(..)
.map(|s| {
Ok(type_statement(
s,
&mut var_types,
&shared_types,
type_constraints,
)?)
})
.collect::<Result<AHashMap<typ::Var, typ::Expr>>>()?;
let weak = state.weak;
let transitions = state
.transitions
.drain(..)
.map(|transition| {
if let untyp::Expr::Var(s) = transition.condition.unwrap_ref() {
if transition.state.is_some()
&& !states_map.contains_key(transition.state.as_ref().unwrap())
{
return Err(TypingError::UnknownState(
transition.state.value.unwrap(),
transition.state.loc,
));
}
if let Some((size, _loc)) = var_types.get(&s.value) {
if weak == false {
return Err(TypingError::LocalVarInUnless(s.loc, s.value.clone()));
}
if *size != 1 {
return Err(TypingError::ExpectedSizeOne(s.loc, *size));
}
Ok((
typ::Var::Local(s.value.clone()),
transition.state.value,
transition.reset,
))
} else {
if let Some((size, _loc)) = shared_types.get(&s.value) {
if *size != 1 {
return Err(TypingError::ExpectedSizeOne(s.loc, *size));
}
Ok((
typ::Var::Shared(s.value.clone()),
transition.state.value,
transition.reset,
))
} else {
Err(TypingError::UnknownVar(s.value.clone(), s.loc))
}
}
} else {
panic!("Should not happen : Expected a variable in transition")
}
})
.collect::<Result<Vec<(typ::Var, Option<typ::Name>, bool)>>>()?;
Ok(typ::State {
transitions,
name: state.name.value,
weak: state.weak,
statements,
})
}
//type a statement, not much to say here.
fn type_statement(
statement: untyp::Statement,
var_types: &mut AHashMap<String, (usize, Pos)>,
shared_types: &AHashMap<String, (usize, Pos)>,
type_constraints: &mut AHashMap<String, (i32, Pos)>,
) -> Result<(typ::Var, typ::Expr)> {
match statement {
untyp::Statement::Assign(mut var_assigns) => {
assert_eq!(
var_assigns.len(),
1,
"Should not happen : Var assign of size different from 1"
);
let untyp::VarAssign { var, expr } = var_assigns.drain(..).next().unwrap();
let sized_expr = type_expr(expr.value, var_types, shared_types, type_constraints)?;
if let Some((_, loc)) = var_types.get(&var.value) {
Err(TypingError::DuplicateVar(var.value, var.loc, *loc))
} else if let Some((size, loc)) = shared_types.get(&var.value) {
if *size == sized_expr.size {
Ok((typ::Var::Shared(var.value), sized_expr))
} else {
let token1 = Token {
loc: *loc,
name: Some(format_var(var.value.to_string())),
length: *size,
};
let token2 = Token {
loc: expr.loc,
name: None,
length: sized_expr.size,
};
Err(TypingError::MismatchedBusSize(token1, token2))
}
} else if let Some((size, loc)) = type_constraints.get(&var.value) {
let size_u = usize::try_from(*size)
.map_err(|_| TypingError::NegativeSizeBus(*loc, *size))?;
if size_u == sized_expr.size {
var_types.insert(var.value.clone(), (sized_expr.size, var.loc));
Ok((typ::Var::Local(var.value), sized_expr))
} else {
let token1 = Token {
loc: *loc,
name: Some(format_var(var.value.to_string())),
length: size_u,
};
let token2 = Token {
loc: expr.loc,
name: None,
length: sized_expr.size,
};
Err(TypingError::MismatchedBusSize(token1, token2))
}
} else {
var_types.insert(var.value.clone(), (sized_expr.size, var.loc));
Ok((typ::Var::Local(var.value), sized_expr))
}
}
_ => panic!(format!(
"Should not happen : Statement with fn call or if struct when typing {:?}",
statement
)),
}
}
//type and expression, same
fn type_expr(
expr: untyp::Expr,
var_types: &AHashMap<String, (usize, Pos)>,
shared_types: &AHashMap<String, (usize, Pos)>,
type_constraints: &mut AHashMap<String, (i32, Pos)>,
) -> Result<typ::Expr> {
match expr {
untyp::Expr::Const(_) | untyp::Expr::Var(_) => {
let sized_expr = type_expr_term(expr, var_types, shared_types, type_constraints)?;
Ok(typ::Sized {
size: sized_expr.size,
value: typ::ExprType::Term(sized_expr),
})
}
untyp::Expr::Last(v) => {
if let Some(s) = shared_types.get(&v.value) {
Ok(typ::Sized {
size: s.0,
value: typ::ExprType::Last(v.value),
})
} else {
Err(TypingError::NonSharedInLast(v.loc, v.value))
}
}
untyp::Expr::Not(expr_term) => {
let sized_expr = type_expr_term(*expr_term, var_types, shared_types, type_constraints)?;
Ok(typ::Sized {
size: sized_expr.size,
value: typ::ExprType::Not(sized_expr),
})
}
untyp::Expr::Slice(expr_term, c1, c2) => {
let sized_expr =
type_expr_term(expr_term.value, var_types, shared_types, type_constraints)?;
let c1 = c1.unwrap_or(untyp::Const::Value(0));
let c2 = c2.unwrap_or(untyp::Const::Value(sized_expr.size as i32));
if let (untyp::Const::Value(i1), untyp::Const::Value(i2)) = (c1, c2) {
let loc = expr_term.loc;
let j1 = usize::try_from(i1)
.map_err(|_| TypingError::IndexOutOfRange(loc, i1, sized_expr.size))?;
let j2 = usize::try_from(i2)
.map_err(|_| TypingError::IndexOutOfRange(loc, i2, sized_expr.size))?;
if j2 > sized_expr.size {
Err(TypingError::IndexOutOfRange(
loc,
j2 as i32,
sized_expr.size,
))
} else {
let mut new_size = j2 as i32 - j1 as i32;
if new_size < 0 {
new_size = 0
}
Ok(typ::Sized {
size: new_size as usize,
value: typ::ExprType::Slice(sized_expr, j1, j2),
})
}
} else {
panic!("Should not happen : unknown const in typing")
}
}
untyp::Expr::BiOp(op, e1, e2) => {
let loc1 = e1.loc;
let loc2 = e2.loc;
let sized_e1 = type_expr_term(e1.value, var_types, shared_types, type_constraints)?;
let sized_e2 = type_expr_term(e2.value, var_types, shared_types, type_constraints)?;
if let untyp::BiOp::Concat = op {
Ok(typ::Sized {
size: sized_e1.size + sized_e2.size,
value: typ::ExprType::BiOp(op, sized_e1, sized_e2),
})
} else {
if sized_e1.size != sized_e2.size {
let token1 = Token {
loc: loc1,
name: None,
length: sized_e1.size,
};
let token2 = Token {
loc: loc2,
name: None,
length: sized_e2.size,
};
Err(TypingError::MismatchedBusSize(token1, token2))
} else {
Ok(typ::Sized {
size: sized_e1.size,
value: typ::ExprType::BiOp(op, sized_e1, sized_e2),
})
}
}
}
untyp::Expr::Mux(e1, e2, e3) => {
let loc1 = e1.loc;
let loc2 = e2.loc;
let loc3 = e3.loc;
let sized_e1 = type_expr_term(e1.value, var_types, shared_types, type_constraints)?;
let sized_e2 = type_expr_term(e2.value, var_types, shared_types, type_constraints)?;
let sized_e3 = type_expr_term(e3.value, var_types, shared_types, type_constraints)?;
if sized_e1.size != 1 {
Err(TypingError::ExpectedSizeOne(loc1, sized_e1.size))
} else if sized_e2.size != sized_e3.size {
let token1 = Token {
loc: loc2,
name: None,
length: sized_e2.size,
};
let token2 = Token {
loc: loc3,
name: None,
length: sized_e3.size,
};
Err(TypingError::MismatchedBusSize(token1, token2))
} else {
Ok(typ::Sized {
size: sized_e2.size,
value: typ::ExprType::Mux(sized_e1, sized_e2, sized_e3),
})
}
}
untyp::Expr::Reg(c, expr_term) => {
let loc1 = c.loc;
let loc2 = expr_term.loc;
let (size, expr) =
type_expr_term_reg(expr_term.value, var_types, shared_types, type_constraints)?;
if let untyp::Const::Value(i) = c.value {
let mut j =
usize::try_from(i).map_err(|_| TypingError::NegativeSizeBus(c.loc, i))?;
if let Some(size) = size {
if size != j && j != 1 {
let token1 = Token {
loc: loc1,
name: None,
length: j,
};
let token2 = Token {
loc: loc2,
name: None,
length: size,
};
return Err(TypingError::MismatchedBusSize(token1, token2));
}
//if the size of the reg is not specified (or is 1), but can be inferred by the compiler,
//it doen't fail, it infers the value
if j == 1 {
j = size
}
}
Ok(typ::Sized {
size: j,
value: typ::ExprType::Reg(typ::Sized {
size: j,
value: expr,
}),
})
} else {
panic!("Should not happen : unknown const while typing")
}
}
untyp::Expr::Ram(untyp::RamStruct {
read_addr: e1,
write_enable: e2,
write_addr: e3,
write_data: e4,
}) => {
let loc1 = e1.loc;
let loc2 = e2.loc;
let loc3 = e3.loc;
let sized_e1 = type_expr_term(e1.value, var_types, shared_types, type_constraints)?;
let sized_e2 = type_expr_term(e2.value, var_types, shared_types, type_constraints)?;
let sized_e3 = type_expr_term(e3.value, var_types, shared_types, type_constraints)?;
let sized_e4 = type_expr_term(e4.value, var_types, shared_types, type_constraints)?;
if sized_e2.size != 1 {
Err(TypingError::ExpectedSizeOne(loc2, sized_e2.size))
} else if sized_e1.size != sized_e3.size {
let token1 = Token {
loc: loc1,
name: None,
length: sized_e1.size,
};
let token2 = Token {
loc: loc3,
name: None,
length: sized_e3.size,
};
Err(TypingError::MismatchedBusSize(token1, token2))
} else {
Ok(typ::Sized {
size: sized_e4.size,
value: typ::ExprType::Ram(typ::RamStruct {
read_addr: sized_e1,
write_enable: sized_e2,
write_addr: sized_e3,
write_data: sized_e4,
}),
})
}
}
untyp::Expr::Rom(untyp::RomStruct {
word_size,
read_addr,
}) => {
let loc = read_addr.loc;
let sized_expr =
type_expr_term(read_addr.value, var_types, shared_types, type_constraints)?;
if let untyp::Const::Value(i) = word_size {
let j = usize::try_from(i).map_err(|_| TypingError::NegativeSizeBus(loc, i))?;
Ok(typ::Sized {
size: j,
value: typ::ExprType::Rom(sized_expr),
})
} else {
panic!("Should not happen : unknown const while typing")
}
}
untyp::Expr::FnCall(_) => panic!("Should not happen : fn call in typing"),
}
}
//type an expression that the compiler assume will be constant or a variable
fn type_expr_term(
expr: untyp::Expr,
var_types: &AHashMap<String, (usize, Pos)>,
shared_types: &AHashMap<String, (usize, Pos)>,
type_constraints: &mut AHashMap<String, (i32, Pos)>,
) -> Result<typ::ExprTerm> {
match expr {
untyp::Expr::Const(c) => match c {
untyp::ConstExpr::Known(v) => Ok(typ::Sized {
size: v.len(),
value: typ::ExprTermType::Const(v),
}),
untyp::ConstExpr::Unknown(b, c) => {
if let untyp::Const::Value(i) = c.value {
let j =
usize::try_from(i).map_err(|_| TypingError::NegativeSizeBus(c.loc, i))?;
Ok(typ::Sized {
size: j,
value: typ::ExprTermType::Const(vec![b; j]),
})
} else {
panic!("Should not happen : unknown const while typing")
}
}
},
untyp::Expr::Var(v) => {
if let Some((size, _loc)) = var_types.get(&v.value) {
Ok(typ::Sized {
size: *size,
value: typ::ExprTermType::Var(typ::Var::Local(v.value)),
})
} else if let Some((size, _loc)) = shared_types.get(&v.value) {
Ok(typ::Sized {
size: *size,
value: typ::ExprTermType::Var(typ::Var::Shared(v.value)),
})
} else if let Some((size, loc)) = type_constraints.get(&v.value) {
let size_u = usize::try_from(*size)
.map_err(|_| TypingError::NegativeSizeBus(*loc, *size))?;
Ok(typ::Sized {
size: size_u,
value: typ::ExprTermType::Var(typ::Var::Local(v.value)),
})
} else {
Err(TypingError::UnknownVar(v.value, v.loc))
}
}
e => panic!(format!(
"Should not happen : non terminal expr at depth 1 in typing {:#?}",
e
)),
}
}
//tries to type an expression inside a reg. If it can't, just returns none, as it is not an error
//(a = reg(a) is valid)
fn type_expr_term_reg(
expr: untyp::Expr,
var_types: &AHashMap<String, (usize, Pos)>,
shared_types: &AHashMap<String, (usize, Pos)>,
type_constraints: &mut AHashMap<String, (i32, Pos)>,
) -> Result<(Option<usize>, typ::ExprTermType)> {
match expr {
untyp::Expr::Const(c) => match c {
untyp::ConstExpr::Known(v) => Ok((Some(v.len()), typ::ExprTermType::Const(v))),
untyp::ConstExpr::Unknown(b, c) => {
if let untyp::Const::Value(i) = c.value {
let j =
usize::try_from(i).map_err(|_| TypingError::NegativeSizeBus(c.loc, i))?;
Ok((Some(j), typ::ExprTermType::Const(vec![b; j])))
} else {
panic!("Should not happen : unknown const while typing")
}
}
},
untyp::Expr::Var(v) => {
if let Some((size, _loc)) = var_types.get(&v.value) {
Ok((
Some(*size),
typ::ExprTermType::Var(typ::Var::Local(v.value)),
))
} else if let Some((size, _loc)) = shared_types.get(&v.value) {
Ok((
Some(*size),
typ::ExprTermType::Var(typ::Var::Shared(v.value)),
))
} else if let Some((size, loc)) = type_constraints.get(&v.value) {
let size_u = usize::try_from(*size)
.map_err(|_| TypingError::NegativeSizeBus(*loc, *size))?;
Ok((
Some(size_u),
typ::ExprTermType::Var(typ::Var::Local(v.value)),
))
} else {
Ok((None, typ::ExprTermType::Var(typ::Var::Local(v.value))))
}
}
_ => panic!("Should not happen : non terminal expr at depth 1 in typing"),
}
}
//from the variable name, it can retrace in which function with which arguments it was.
//TODO : make it work the same, but without the ugly hack.
fn format_var(var: String) -> String {
if var.starts_with('$') {
let vec: Vec<&str> = var.split('$').filter(|s| *s != "").collect();
let _typ = vec[0];
let fn_name = vec[1];
let args = vec[2];
let var_name = vec[3];
format!(
"\"{}\" in call of function \"{}\" with arguments{}",
var_name.split('#').next().unwrap(),
fn_name,
format_args(args)
)
} else {
var
}
}
fn format_args(args: &str) -> String {
args.split('|')
.filter(|s| *s != "")
.map(|v| v.split('_').collect::<Vec<&str>>())
.map(|v| format!(" {} = {},", v[0], v[1]))
.collect::<String>()
}