rust/tests/mir-opt/early_otherwise_branch_3_element_tuple.rs

50 lines
1.6 KiB
Rust

//@ test-mir-pass: EarlyOtherwiseBranch
//@ compile-flags: -Zmir-enable-passes=+UnreachableEnumBranching
enum Option2<T> {
Some(T),
None,
Other,
}
// FIXME: `switchInt` will have three targets after `UnreachableEnumBranching`,
// otherwise is unreachable. We can consume the UB fact to transform back to if else pattern.
// EMIT_MIR early_otherwise_branch_3_element_tuple.opt1.EarlyOtherwiseBranch.diff
fn opt1(x: Option<u32>, y: Option<u32>, z: Option<u32>) -> u32 {
// CHECK-LABEL: fn opt1(
// CHECK: bb0: {
// CHECK: [[LOCAL1:_.*]] = discriminant({{.*}});
// CHECK-NOT: Ne
// CHECK-NOT: discriminant
// CHECK: switchInt(move [[LOCAL1]]) -> [
// CHECK-NEXT: }
match (x, y, z) {
(Some(a), Some(b), Some(c)) => 0,
(None, None, None) => 2,
_ => 1,
}
}
// EMIT_MIR early_otherwise_branch_3_element_tuple.opt2.EarlyOtherwiseBranch.diff
fn opt2(x: Option2<u32>, y: Option2<u32>, z: Option2<u32>) -> u32 {
// CHECK-LABEL: fn opt2(
// CHECK: let mut [[CMP_LOCAL:_.*]]: bool;
// CHECK: bb0: {
// CHECK: [[LOCAL1:_.*]] = discriminant({{.*}});
// CHECK: [[LOCAL2:_.*]] = discriminant({{.*}});
// CHECK: [[CMP_LOCAL]] = Ne([[LOCAL1]], move [[LOCAL2]]);
// CHECK: switchInt(move [[CMP_LOCAL]]) -> [
// CHECK-NEXT: }
match (x, y, z) {
(Option2::Some(a), Option2::Some(b), Option2::Some(c)) => 0,
(Option2::None, Option2::None, Option2::None) => 2,
(Option2::Other, Option2::Other, Option2::Other) => 3,
_ => 1,
}
}
fn main() {
opt1(None, Some(0), None);
opt2(Option2::None, Option2::Some(0), Option2::None);
}