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//@ test-mir-pass: EarlyOtherwiseBranch
//@ compile-flags: -Zmir-enable-passes=+UnreachableEnumBranching
// Tests various cases that the `early_otherwise_branch` opt should *not* optimize
// From #78496
enum E<'a> {
Empty,
Some(&'a E<'a>),
}
// EMIT_MIR early_otherwise_branch_soundness.no_downcast.EarlyOtherwiseBranch.diff
fn no_downcast(e: &E) -> u32 {
// CHECK-LABEL: fn no_downcast(
// CHECK: bb0: {
// CHECK: [[LOCAL1:_.*]] = discriminant({{.*}});
// CHECK-NOT: Ne
// CHECK-NOT: discriminant
// CHECK: switchInt(move [[LOCAL1]]) -> [
// CHECK-NEXT: }
if let E::Some(E::Some(_)) = e { 1 } else { 2 }
}
// SAFETY: if `a` is `Some`, `b` must point to a valid, initialized value
// EMIT_MIR early_otherwise_branch_soundness.no_deref_ptr.EarlyOtherwiseBranch.diff
unsafe fn no_deref_ptr(a: Option<i32>, b: *const Option<i32>) -> i32 {
// CHECK-LABEL: fn no_deref_ptr(
// CHECK: bb0: {
// CHECK: [[LOCAL1:_.*]] = discriminant({{.*}});
// CHECK-NOT: Ne
// CHECK-NOT: discriminant
// CHECK: switchInt(move [[LOCAL1]]) -> [
// CHECK-NEXT: }
match a {
// `*b` being correct depends on `a == Some(_)`
Some(_) => match *b {
Some(v) => v,
_ => 0,
},
_ => 0,
}
}
fn main() {
no_downcast(&E::Empty);
unsafe { no_deref_ptr(None, std::ptr::null()) };
}
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