add recursive unions

This commit is contained in:
Folkert 2022-08-06 17:40:12 +02:00
parent 546b702740
commit be4e98e076
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GPG key ID: 1F17F6FFD112B97C
2 changed files with 149 additions and 19 deletions

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@ -536,7 +536,78 @@ fn build_clone_tag_help<'a, 'ctx, 'env>(
}
}
}
Recursive(_) => todo!(),
Recursive(tags) => {
let id = get_tag_id(env, parent, &union_layout, tag_value);
let switch_block = env.context.append_basic_block(parent, "switch_block");
env.builder.build_unconditional_branch(switch_block);
let mut cases = Vec::with_capacity_in(tags.len(), env.arena);
for (tag_id, field_layouts) in tags.iter().enumerate() {
let block = env.context.append_basic_block(parent, "tag_id_modify");
env.builder.position_at_end(block);
// write the "pointer" of the current offset
write_pointer_with_tag_id(env, ptr, offset, extra_offset, union_layout, tag_id);
let tag_value = tag_pointer_clear_tag_id(env, tag_value.into_pointer_value());
let raw_data_ptr = env
.builder
.build_struct_gep(tag_value, RocUnion::TAG_DATA_INDEX, "tag_data")
.unwrap();
let layout = Layout::struct_no_name_order(field_layouts);
let layout = if union_layout.stores_tag_id_in_pointer(env.target_info) {
layout
} else {
Layout::struct_no_name_order(
env.arena.alloc([layout, union_layout.tag_id_layout()]),
)
};
let basic_type = basic_type_from_layout(env, &layout);
let data_ptr = env.builder.build_pointer_cast(
raw_data_ptr,
basic_type.ptr_type(AddressSpace::Generic),
"data_ptr",
);
let data = env.builder.build_load(data_ptr, "load_data");
let (width, _) = union_layout.data_size_and_alignment(env.target_info);
let cursors = Cursors {
offset: extra_offset,
extra_offset: env.builder.build_int_add(
extra_offset,
env.ptr_int().const_int(width as _, false),
"new_offset",
),
};
let when_recursive = WhenRecursive::Loop(union_layout);
let answer =
build_clone(env, layout_ids, ptr, cursors, data, layout, when_recursive);
env.builder.build_return(Some(&answer));
cases.push((id.get_type().const_int(tag_id as u64, false), block));
}
env.builder.position_at_end(switch_block);
match cases.pop() {
Some((_, default)) => {
env.builder.build_switch(id, default, &cases);
}
None => {
// we're serializing an empty tag union; this code is effectively unreachable
env.builder.build_unreachable();
}
}
}
NonNullableUnwrapped(_) => todo!(),
NullableWrapped {
nullable_id,
@ -565,23 +636,8 @@ fn build_clone_tag_help<'a, 'ctx, 'env>(
let block = env.context.append_basic_block(parent, "tag_id_modify");
env.builder.position_at_end(block);
// write the "pointer" af the current offset
{
// first, store tag id as u32
let tag_id_intval = env.context.i32_type().const_int(i as _, false);
build_copy(env, ptr, offset, tag_id_intval.into());
// increment offset by 4
let four = env.ptr_int().const_int(4, false);
let offset = env.builder.build_int_add(offset, four, "");
// cast to u32
let extra_offset =
env.builder
.build_int_cast(extra_offset, env.context.i32_type(), "");
build_copy(env, ptr, offset, extra_offset.into());
}
// write the "pointer" of the current offset
write_pointer_with_tag_id(env, ptr, offset, extra_offset, union_layout, i);
let fields = if i >= nullable_id as _ {
other_tags[i - 1]
@ -715,6 +771,34 @@ fn build_clone_tag_help<'a, 'ctx, 'env>(
}
}
fn write_pointer_with_tag_id<'a, 'ctx, 'env>(
env: &Env<'a, 'ctx, 'env>,
ptr: PointerValue<'ctx>,
offset: IntValue<'ctx>,
extra_offset: IntValue<'ctx>,
union_layout: UnionLayout<'a>,
tag_id: usize,
) {
if union_layout.stores_tag_id_in_pointer(env.target_info) {
// first, store tag id as u32
let tag_id_intval = env.context.i32_type().const_int(tag_id as _, false);
build_copy(env, ptr, offset, tag_id_intval.into());
// increment offset by 4
let four = env.ptr_int().const_int(4, false);
let offset = env.builder.build_int_add(offset, four, "");
// cast to u32
let extra_offset = env
.builder
.build_int_cast(extra_offset, env.context.i32_type(), "");
build_copy(env, ptr, offset, extra_offset.into());
} else {
build_copy(env, ptr, offset, extra_offset.into());
}
}
fn build_copy<'a, 'ctx, 'env>(
env: &Env<'a, 'ctx, 'env>,
ptr: PointerValue<'ctx>,