Tag don't unroll recursive types

This commit is contained in:
Folkert 2021-07-16 18:10:55 +02:00
parent 7dd440f642
commit 97f15bbb49

View File

@ -4180,6 +4180,18 @@ fn convert_tag_union<'a>(
let field_symbols;
let opt_tag_id_symbol;
// we must derive the union layout from the whole_var, building it up
// from `layouts` would unroll recursive tag unions, and that leads to
// problems down the line because we hash layouts and an unrolled
// version is not the same as the minimal version.
let union_layout = match return_on_layout_error!(
env,
layout_cache.from_var(env.arena, variant_var, env.subs)
) {
Layout::Union(ul) => ul,
_ => unreachable!(),
};
use WrappedVariant::*;
let (tag, union_layout) = match variant {
Recursive { sorted_tag_layouts } => {
@ -4201,19 +4213,6 @@ fn convert_tag_union<'a>(
layouts.push(arg_layouts);
}
// we must derive the union layout from the whole_var, building it up
// from `layouts` would unroll recursive tag unions, and that leads to
// problems down the line because we hash layouts and an unrolled
// version is not the same as the minimal version.
debug_assert!(layouts.len() > 1);
let union_layout = match return_on_layout_error!(
env,
layout_cache.from_var(env.arena, variant_var, env.subs)
) {
Layout::Union(ul) => ul,
_ => unreachable!(),
};
let tag = Expr::Tag {
tag_layout: union_layout,
tag_name,
@ -4225,8 +4224,8 @@ fn convert_tag_union<'a>(
(tag, union_layout)
}
NonNullableUnwrapped {
fields,
tag_name: wrapped_tag_name,
..
} => {
debug_assert_eq!(tag_name, wrapped_tag_name);
@ -4240,8 +4239,6 @@ fn convert_tag_union<'a>(
temp.into_bump_slice()
};
let union_layout = UnionLayout::NonNullableUnwrapped(fields);
let tag = Expr::Tag {
tag_layout: union_layout,
tag_name,
@ -4270,8 +4267,6 @@ fn convert_tag_union<'a>(
layouts.push(arg_layouts);
}
let union_layout = UnionLayout::NonRecursive(layouts.into_bump_slice());
let tag = Expr::Tag {
tag_layout: union_layout,
tag_name,
@ -4283,9 +4278,7 @@ fn convert_tag_union<'a>(
(tag, union_layout)
}
NullableWrapped {
nullable_id,
nullable_name: _,
sorted_tag_layouts,
sorted_tag_layouts, ..
} => {
opt_tag_id_symbol = None;
@ -4304,11 +4297,6 @@ fn convert_tag_union<'a>(
layouts.push(arg_layouts);
}
let union_layout = UnionLayout::NullableWrapped {
nullable_id,
other_tags: layouts.into_bump_slice(),
};
let tag = Expr::Tag {
tag_layout: union_layout,
tag_name,
@ -4319,12 +4307,7 @@ fn convert_tag_union<'a>(
(tag, union_layout)
}
NullableUnwrapped {
nullable_id,
nullable_name: _,
other_name: _,
other_fields,
} => {
NullableUnwrapped { .. } => {
// FIXME drop tag
let tag_id_symbol = env.unique_symbol();
opt_tag_id_symbol = Some(tag_id_symbol);
@ -4337,11 +4320,6 @@ fn convert_tag_union<'a>(
temp.into_bump_slice()
};
let union_layout = UnionLayout::NullableUnwrapped {
nullable_id,
other_fields,
};
let tag = Expr::Tag {
tag_layout: union_layout,
tag_name,