language-servers/roc
1
0
Fork 0
mirror of https://github.com/roc-lang/roc.git synced 2025-09-28 22:34:45 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 6

make instantiate_rigids_help use a loop/stack

Browse source
This commit is contained in:
Folkert 2021-11-20 00:24:46 +01:00
parent 991420731d
commit 497bc2db02
2 changed files with 69 additions and 91 deletions
Download patch file Download diff file Expand all files Collapse all files

154
compiler/solve/src/solve.rs
View file

@ -1259,122 +1259,100 @@ pub fn instantiate_rigids(subs: &mut Subs, var: Variable) {
subs.restore(var);
}
fn instantiate_rigids_help(subs: &mut Subs, max_rank: Rank, var: Variable) {
use roc_types::subs::Content::*;
use roc_types::subs::FlatType::*;
fn instantiate_rigids_help(subs: &mut Subs, max_rank: Rank, initial: Variable) {
let mut stack = vec![initial];
let desc = subs.get_without_compacting(var);
if desc.copy.is_some() {
return;
macro_rules! var_slice {
($variable_subs_slice:expr) => {{
&subs.variables[$variable_subs_slice.slice.start as usize..]
[..$variable_subs_slice.slice.length as usize]
}};
}
// Link the original variable to the new variable. This lets us
// avoid making multiple copies of the variable we are instantiating.
//
// Need to do this before recursively copying to avoid looping.
subs.set(
var,
Descriptor {
content: desc.content.clone(),
rank: desc.rank,
mark: Mark::NONE,
copy: var.into(),
},
);
while let Some(var) = stack.pop() {
if subs.get_ref(var).copy.is_some() {
continue;
}
// Now we recursively copy the content of the variable.
// We have already marked the variable as copied, so we
// will not repeat this work or crawl this variable again.
match desc.content {
Structure(flat_type) => {
match flat_type {
subs.modify(var, |desc| {
desc.rank = Rank::NONE;
desc.mark = Mark::NONE;
desc.copy = OptVariable::from(var);
});
use Content::*;
use FlatType::*;
let desc = subs.get_ref(var);
match &desc.content {
RigidVar(name) => {
// what it's all about: convert the rigid var into a flex var
let name = name.clone();
subs.set(
var,
Descriptor {
content: FlexVar(Some(name)),
rank: max_rank,
mark: Mark::NONE,
copy: OptVariable::NONE,
},
);
}
FlexVar(_) | Error => (),
RecursionVar { structure, .. } => {
stack.push(*structure);
}
Structure(flat_type) => match flat_type {
Apply(_, args) => {
for var_index in args.into_iter() {
let var = subs[var_index];
instantiate_rigids_help(subs, max_rank, var);
}
stack.extend(var_slice!(*args));
}
Func(arg_vars, closure_var, ret_var) => {
instantiate_rigids_help(subs, max_rank, ret_var);
instantiate_rigids_help(subs, max_rank, closure_var);
stack.extend(var_slice!(*arg_vars));
for index in arg_vars.into_iter() {
let var = subs[index];
instantiate_rigids_help(subs, max_rank, var);
}
stack.push(*ret_var);
stack.push(*closure_var);
}
EmptyRecord | EmptyTagUnion | Erroneous(_) => {}
EmptyRecord => (),
EmptyTagUnion => (),
Record(fields, ext_var) => {
for index in fields.iter_variables() {
let var = subs[index];
instantiate_rigids_help(subs, max_rank, var);
}
stack.extend(var_slice!(fields.variables()));
instantiate_rigids_help(subs, max_rank, ext_var);
stack.push(*ext_var);
}
TagUnion(tags, ext_var) => {
for (_, index) in tags.iter_all() {
let slice = subs[index];
for var_index in slice {
let var = subs[var_index];
instantiate_rigids_help(subs, max_rank, var);
}
for slice_index in tags.variables() {
let slice = subs.variable_slices[slice_index.start as usize];
stack.extend(var_slice!(slice));
}
instantiate_rigids_help(subs, max_rank, ext_var);
stack.push(*ext_var);
}
FunctionOrTagUnion(_tag_name, _symbol, ext_var) => {
instantiate_rigids_help(subs, max_rank, ext_var);
FunctionOrTagUnion(_, _, ext_var) => {
stack.push(*ext_var);
}
RecursiveTagUnion(rec_var, tags, ext_var) => {
instantiate_rigids_help(subs, max_rank, rec_var);
for (_, index) in tags.iter_all() {
let slice = subs[index];
for var_index in slice {
let var = subs[var_index];
instantiate_rigids_help(subs, max_rank, var);
}
for slice_index in tags.variables() {
let slice = subs.variable_slices[slice_index.start as usize];
stack.extend(var_slice!(slice));
}
instantiate_rigids_help(subs, max_rank, ext_var);
stack.push(*ext_var);
stack.push(*rec_var);
}
};
}
FlexVar(_) | Error => {}
Erroneous(_) => (),
},
Alias(_, args, var) => {
stack.extend(var_slice!(args.variables()));
RecursionVar { structure, .. } => {
instantiate_rigids_help(subs, max_rank, structure);
}
RigidVar(name) => {
// what it's all about: convert the rigid var into a flex var
subs.set(
var,
Descriptor {
content: FlexVar(Some(name)),
rank: max_rank,
mark: Mark::NONE,
copy: OptVariable::NONE,
},
);
}
Alias(_symbol, args, real_type_var) => {
for var_index in args.variables().into_iter() {
let var = subs[var_index];
instantiate_rigids_help(subs, max_rank, var);
stack.push(*var);
}
instantiate_rigids_help(subs, max_rank, real_type_var);
}
}
}