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//@ test-mir-pass: EarlyOtherwiseBranch
//@ compile-flags: -Zmir-enable-passes=+UnreachableEnumBranching
enum Option2<T> {
Some(T),
None,
Other,
}
// We can't optimize it because y may be an invalid value.
// EMIT_MIR early_otherwise_branch.opt1.EarlyOtherwiseBranch.diff
fn opt1(x: Option<u32>, y: 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) {
(Some(a), Some(b)) => 0,
_ => 1,
}
}
// 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.opt2.EarlyOtherwiseBranch.diff
fn opt2(x: Option<u32>, y: Option<u32>) -> u32 {
// CHECK-LABEL: fn opt2(
// CHECK: bb0: {
// CHECK: [[LOCAL1:_.*]] = discriminant({{.*}});
// CHECK-NOT: Ne
// CHECK-NOT: discriminant
// CHECK: switchInt(move [[LOCAL1]]) -> [
// CHECK-NEXT: }
match (x, y) {
(Some(a), Some(b)) => 0,
(None, None) => 2,
_ => 1,
}
}
// optimize despite different types
// EMIT_MIR early_otherwise_branch.opt3.EarlyOtherwiseBranch.diff
fn opt3(x: Option2<u32>, y: Option2<bool>) -> u32 {
// CHECK-LABEL: fn opt3(
// CHECK: let mut [[CMP_LOCAL:_.*]]: bool;
// CHECK: bb0: {
// CHECK: [[LOCAL1:_.*]] = discriminant({{.*}});
// CHECK: [[LOCAL2:_.*]] = discriminant({{.*}});
// CHECK: [[CMP_LOCAL]] = Ne(copy [[LOCAL1]], move [[LOCAL2]]);
// CHECK: switchInt(move [[CMP_LOCAL]]) -> [
// CHECK-NEXT: }
match (x, y) {
(Option2::Some(a), Option2::Some(b)) => 0,
(Option2::None, Option2::None) => 2,
(Option2::Other, Option2::Other) => 3,
_ => 1,
}
}
// EMIT_MIR early_otherwise_branch.opt4.EarlyOtherwiseBranch.diff
fn opt4(x: Option2<u32>, y: Option2<u32>) -> u32 {
// CHECK-LABEL: fn opt4(
// CHECK: let mut [[CMP_LOCAL:_.*]]: bool;
// CHECK: bb0: {
// CHECK: [[LOCAL1:_.*]] = discriminant({{.*}});
// CHECK: [[LOCAL2:_.*]] = discriminant({{.*}});
// CHECK: [[CMP_LOCAL]] = Ne(copy [[LOCAL1]], move [[LOCAL2]]);
// CHECK: switchInt(move [[CMP_LOCAL]]) -> [
// CHECK-NEXT: }
match (x, y) {
(Option2::Some(a), Option2::Some(b)) => 0,
(Option2::None, Option2::None) => 2,
(Option2::Other, Option2::Other) => 3,
_ => 1,
}
}
// EMIT_MIR early_otherwise_branch.opt5.EarlyOtherwiseBranch.diff
fn opt5(x: u32, y: u32) -> u32 {
// CHECK-LABEL: fn opt5(
// CHECK: let mut [[CMP_LOCAL:_.*]]: bool;
// CHECK: bb0: {
// CHECK: [[CMP_LOCAL]] = Ne(
// CHECK: switchInt(move [[CMP_LOCAL]]) -> [
// CHECK-NEXT: }
match (x, y) {
(1, 1) => 4,
(2, 2) => 5,
(3, 3) => 6,
_ => 0,
}
}
// EMIT_MIR early_otherwise_branch.opt5_failed.EarlyOtherwiseBranch.diff
fn opt5_failed(x: u32, y: u32) -> u32 {
// CHECK-LABEL: fn opt5_failed(
// CHECK: bb0: {
// CHECK-NOT: Ne(
// CHECK: switchInt(
// CHECK-NEXT: }
match (x, y) {
(1, 1) => 4,
(2, 2) => 5,
(3, 2) => 6,
_ => 0,
}
}
// EMIT_MIR early_otherwise_branch.opt5_failed_type.EarlyOtherwiseBranch.diff
fn opt5_failed_type(x: u32, y: u64) -> u32 {
// CHECK-LABEL: fn opt5_failed_type(
// CHECK: bb0: {
// CHECK-NOT: Ne(
// CHECK: switchInt(
// CHECK-NEXT: }
match (x, y) {
(1, 1) => 4,
(2, 2) => 5,
(3, 3) => 6,
_ => 0,
}
}
fn main() {
opt1(None, Some(0));
opt2(None, Some(0));
opt3(Option2::None, Option2::Some(false));
opt4(Option2::None, Option2::Some(0));
opt5(0, 0);
opt5_failed(0, 0);
}
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