v3: preserve array map pointer result origins

Author: medvednikov

vlib/v3/tests/review_transform_regressions_test.v

@@ -5551,6 +5551,108 @@ fn main() {
 	assert out == 'four\nfour'
 }
 
+fn test_array_map_keeps_temporary_source_through_dump_result() {
+	v3_bin := build_v3_review_transform_ownership()
+	source := 'struct Item {
+	text string
+}
+
+fn make_items() []Item {
+	return [Item{
+		text: "four"
+	}]
+}
+
+fn main() {
+	values := make_items().map(dump(&it))
+	println(values[0].text)
+}
+'
+	c_source := gen_c_from_source_with_flags(v3_bin, 'array_map_dump_pointer_result_c',
+		'-ownership', source)
+	main_body := c_fn_body(c_source, 'int main(int argc, char** argv) {')
+	assert !main_body.contains('array__free(&(__map_source_'), main_body
+}
+
+fn test_array_map_keeps_temporary_source_through_inherited_struct_update_field() {
+	v3_bin := build_v3_review_transform_ownership()
+	source := 'struct Item {
+	text string
+}
+
+struct PointerBox {
+	value &Item
+	other int
+}
+
+fn make_items() []Item {
+	return [Item{
+		text: "four"
+	}]
+}
+
+fn main() {
+	values := make_items().map(PointerBox{
+		...PointerBox{
+			value: &it
+		}
+		other: 1
+	}.value)
+	println(values[0].text)
+}
+'
+	c_source := gen_c_from_source_with_flags(v3_bin, 'array_map_assoc_pointer_result_c',
+		'-ownership', source)
+	main_body := c_fn_body(c_source, 'int main(int argc, char** argv) {')
+	assert !main_body.contains('array__free(&(__map_source_'), main_body
+	out := run_good_with_flags(v3_bin, 'array_map_assoc_pointer_result', '-ownership', source)
+	assert out == 'four'
+}
+
+fn test_array_map_drops_source_for_unselected_helper_result_field() {
+	v3_bin := build_v3_review_transform_ownership()
+	source := 'struct Item {
+	text string
+}
+
+struct PointerPair {
+	source   &Item
+	external &Item
+}
+
+fn make_items() []Item {
+	return [Item{
+		text: "source"
+	}]
+}
+
+fn pair(source &Item, external &Item) PointerPair {
+	return unsafe {
+		PointerPair{
+			source: source
+			external: external
+		}
+	}
+}
+
+fn main() {
+	external := Item{
+		text: "external"
+	}
+	selected := make_items().map(pair(&it, &external).external)
+	println(selected[0].text)
+}
+'
+	c_source := gen_c_from_source_with_flags(v3_bin, 'array_map_helper_external_field_c',
+		'-ownership', source)
+	main_body := c_fn_body(c_source, 'int main(int argc, char** argv) {')
+	source_drop_pos := main_body.index('array__free(&(') or { -1 }
+	result_move_pos := main_body.index('Array selected = ') or { -1 }
+	assert source_drop_pos >= 0 && source_drop_pos < result_move_pos, main_body
+	out := run_good_with_flags(v3_bin, 'array_map_helper_external_field', '-ownership', source)
+	assert out == 'external'
+}
+
 fn test_array_map_drops_source_for_unrelated_pointer_result() {
 	v3_bin := build_v3_review_transform_ownership()
 	source := 'struct Item {

vlib/v3/transform/array.v

@@ -2801,7 +2801,7 @@ fn (mut t Transformer) array_map_expr_result_retains_element_address(id flat.Nod
 		return t.array_map_lvalue_is_rooted_at_ident(t.a.child(&node, 0), name)
 	}
 	match node.kind {
-		.paren, .cast_expr, .as_expr, .expr_stmt, .field_init {
+		.paren, .cast_expr, .as_expr, .dump_expr, .expr_stmt, .field_init {
 			return node.children_count > 0
 				&& t.array_map_expr_result_retains_element_address(t.a.child(&node, 0), name)
 		}
@@ -2827,9 +2827,16 @@ fn (mut t Transformer) array_map_expr_result_retains_element_address(id flat.Nod
 			return false
 		}
 		.selector {
-			return node.children_count > 0
-				&& t.array_map_selector_result_retains_element_address(t.a.child(&node, 0),
-					node.value, name)
+			if node.children_count == 0 {
+				return false
+			}
+			for source_arg in t.tc.ownership_call_result_source_args(id) {
+				if t.array_map_expr_result_retains_element_address(source_arg, name) {
+					return true
+				}
+			}
+			return t.array_map_selector_result_retains_element_address(t.a.child(&node, 0),
+				node.value, name)
 		}
 		.index {
 			return t.array_map_index_result_retains_element_address(node, name)
@@ -2897,6 +2904,10 @@ fn (mut t Transformer) array_map_selector_result_retains_element_address(base_id
 					elem_name)
 			}
 		}
+		if base.kind == .assoc && base.children_count > 0 {
+			return t.array_map_selector_result_retains_element_address(t.a.child(&base, 0),
+				field_name, elem_name)
+		}
 		return false
 	}
 	return t.array_map_expr_result_retains_element_address(base_id, elem_name)

vlib/v3/types/checker_ownership_d_ownership.v

@@ -10536,7 +10536,8 @@ pub fn (mut tc TypeChecker) ownership_call_result_source_args(id flat.NodeId) []
 	if tc.ownership == unsafe { nil } {
 		return []flat.NodeId{}
 	}
-	call_id := tc.ownership_unwrap_expr(id)
+	projection := tc.ownership_call_projection(id) or { return []flat.NodeId{} }
+	call_id := projection.call_id
 	if !tc.valid_node_id(call_id) {
 		return []flat.NodeId{}
 	}
@@ -10553,11 +10554,20 @@ pub fn (mut tc TypeChecker) ownership_call_result_source_args(id flat.NodeId) []
 		}
 	}
 	for slot in tc.ownership_state().ownership_fn_return_params[call_name] {
+		if projection.suffix.len > 0 && slot.slot_idx != 0 {
+			continue
+		}
 		if slot.param_idx !in param_indices {
 			param_indices << slot.param_idx
 		}
 	}
 	for desc in tc.ownership_state().ownership_fn_return_param_descs[call_name] {
+		if projection.suffix.len > 0
+			&& (desc.slot_idx != 0
+			|| (desc.target_suffix.len > 0
+			&& !ownership_storage_keys_overlap(desc.target_suffix, projection.suffix))) {
+			continue
+		}
 		if desc.param_idx !in param_indices {
 			param_indices << desc.param_idx
 		}