fix List.map2

This commit is contained in:
Folkert 2021-05-19 16:07:50 +02:00
parent 87b9f866d3
commit d2b0ecdd04
6 changed files with 77 additions and 88 deletions

View file

@ -242,9 +242,41 @@ pub fn listMapWithIndex(
}
}
pub fn listMap2(list1: RocList, list2: RocList, transform: Opaque, caller: Caller2, alignment: usize, a_width: usize, b_width: usize, c_width: usize, dec_a: Dec, dec_b: Dec) callconv(.C) RocList {
fn decrementTail(list: RocList, start_index: usize, element_width: usize, dec: Dec) void {
if (list.bytes) |source| {
var i = start_index;
while (i < list.len()) : (i += 1) {
const element = source + i * element_width;
dec(element);
}
}
}
pub fn listMap2(
list1: RocList,
list2: RocList,
caller: Caller2,
data: Opaque,
inc_n_data: IncN,
data_is_owned: bool,
alignment: usize,
a_width: usize,
b_width: usize,
c_width: usize,
dec_a: Dec,
dec_b: Dec,
) callconv(.C) RocList {
const output_length = std.math.min(list1.len(), list2.len());
// if the lists don't have equal length, we must consume the remaining elements
// In this case we consume by (recursively) decrementing the elements
decrementTail(list1, output_length, a_width, dec_a);
decrementTail(list2, output_length, b_width, dec_b);
if (data_is_owned) {
inc_n_data(data, output_length);
}
if (list1.bytes) |source_a| {
if (list2.bytes) |source_b| {
const output = RocList.allocate(std.heap.c_allocator, alignment, output_length, c_width);
@ -255,49 +287,14 @@ pub fn listMap2(list1: RocList, list2: RocList, transform: Opaque, caller: Calle
const element_a = source_a + i * a_width;
const element_b = source_b + i * b_width;
const target = target_ptr + i * c_width;
caller(transform, element_a, element_b, target);
caller(data, element_a, element_b, target);
}
// if the lists don't have equal length, we must consume the remaining elements
// In this case we consume by (recursively) decrementing the elements
if (list1.len() > output_length) {
while (i < list1.len()) : (i += 1) {
const element_a = source_a + i * a_width;
dec_a(element_a);
}
} else if (list2.len() > output_length) {
while (i < list2.len()) : (i += 1) {
const element_b = source_b + i * b_width;
dec_b(element_b);
}
}
utils.decref(std.heap.c_allocator, alignment, list1.bytes, list1.len() * a_width);
utils.decref(std.heap.c_allocator, alignment, list2.bytes, list2.len() * b_width);
return output;
} else {
// consume list1 elements (we know there is at least one because the list1.bytes pointer is non-null
var i: usize = 0;
while (i < list1.len()) : (i += 1) {
const element_a = source_a + i * a_width;
dec_a(element_a);
}
utils.decref(std.heap.c_allocator, alignment, list1.bytes, list1.len() * a_width);
return RocList.empty();
}
} else {
// consume list2 elements (if any)
if (list2.bytes) |source_b| {
var i: usize = 0;
while (i < list2.len()) : (i += 1) {
const element_b = source_b + i * b_width;
dec_b(element_b);
}
utils.decref(std.heap.c_allocator, alignment, list2.bytes, list2.len() * b_width);
}
return RocList.empty();
}
}

View file

@ -930,7 +930,7 @@ fn strConcat(allocator: *Allocator, result_in_place: InPlace, arg1: RocStr, arg2
return RocStr.clone(allocator, result_in_place, arg2);
} else if (arg2.isEmpty()) {
// the first argument is owned, so we can return it without cloning
return RocStr.clone(allocator, result_in_place, arg1);
return arg1;
} else {
const combined_length = arg1.len() + arg2.len();