diff options
| -rw-r--r-- | compiler/rustc_mir/src/transform/early_otherwise_branch.rs | 9 |
1 files changed, 4 insertions, 5 deletions
diff --git a/compiler/rustc_mir/src/transform/early_otherwise_branch.rs b/compiler/rustc_mir/src/transform/early_otherwise_branch.rs index 5829c522935..f28a4b46715 100644 --- a/compiler/rustc_mir/src/transform/early_otherwise_branch.rs +++ b/compiler/rustc_mir/src/transform/early_otherwise_branch.rs @@ -283,7 +283,7 @@ impl<'a, 'tcx> Helper<'a, 'tcx> { return None; } - // when one place is the projection of the other, it's not safe to calculate their discriminant values sequentially. + // when the second place is a projection of the first one, it's not safe to calculate their discriminant values sequentially. // for example, this should not be optimized: // // ```rust @@ -294,18 +294,17 @@ impl<'a, 'tcx> Helper<'a, 'tcx> { // ```mir // bb0: { // _2 = discriminant(*_1) - // switchInt(move _2) -> [...] + // switchInt(_2) -> [...] // } // bb1: { // _3 = discriminant(*(((*_1) as Some).0: &E)) - // switchInt(move _3) -> [...] + // switchInt(_3) -> [...] // } // ``` let discr_place = discr_info.place_of_adt_discr_read; let this_discr_place = this_bb_discr_info.place_of_adt_discr_read; if discr_place.local == this_discr_place.local - && (discr_place.projection.starts_with(this_discr_place.projection) - || this_discr_place.projection.starts_with(discr_place.projection)) + && this_discr_place.projection.starts_with(discr_place.projection) { trace!("NO: one target is the projection of another"); return None; |