diff --git a/src/librustc_mir/interpret/eval_context.rs b/src/librustc_mir/interpret/eval_context.rs index 3375b6edf1a..020abbf94c5 100644 --- a/src/librustc_mir/interpret/eval_context.rs +++ b/src/librustc_mir/interpret/eval_context.rs @@ -148,14 +148,14 @@ type EvalSnapshot<'a, 'mir, 'tcx, M> pub(crate) struct InfiniteLoopDetector<'a, 'mir, 'tcx: 'a + 'mir, M: Machine<'mir, 'tcx>> { /// The set of all `EvalSnapshot` *hashes* observed by this detector. /// - /// Not a proper bloom filter. - bloom: FxHashSet, + /// When a collision occurs in this table, we store the full snapshot in `snapshots`. + hashes: FxHashSet, /// The set of all `EvalSnapshot`s observed by this detector. /// - /// An `EvalSnapshot` will only be fully cloned once it has caused a collision - /// in `bloom`. As a result, the detector must observe *two* full cycles of - /// an infinite loop before it triggers. + /// An `EvalSnapshot` will only be fully cloned once it has caused a collision in `hashes`. As + /// a result, the detector must observe at least *two* full cycles of an infinite loop before + /// it triggers. snapshots: FxHashSet>, } @@ -165,7 +165,7 @@ impl<'a, 'mir, 'tcx, M> Default for InfiniteLoopDetector<'a, 'mir, 'tcx, M> { fn default() -> Self { InfiniteLoopDetector { - bloom: FxHashSet::default(), + hashes: FxHashSet::default(), snapshots: FxHashSet::default(), } } @@ -177,7 +177,7 @@ impl<'a, 'mir, 'tcx, M> InfiniteLoopDetector<'a, 'mir, 'tcx, M> { /// Returns `true` if the loop detector has not yet observed a snapshot. pub fn is_empty(&self) -> bool { - self.bloom.is_empty() + self.hashes.is_empty() } pub fn observe_and_analyze( @@ -192,7 +192,7 @@ impl<'a, 'mir, 'tcx, M> InfiniteLoopDetector<'a, 'mir, 'tcx, M> snapshot.hash(&mut fx); let hash = fx.finish(); - if self.bloom.insert(hash) { + if self.hashes.insert(hash) { // No collision return Ok(()) } diff --git a/src/librustc_mir/interpret/step.rs b/src/librustc_mir/interpret/step.rs index b0c08304969..2025db48718 100644 --- a/src/librustc_mir/interpret/step.rs +++ b/src/librustc_mir/interpret/step.rs @@ -16,10 +16,10 @@ impl<'a, 'mir, 'tcx, M: Machine<'mir, 'tcx>> EvalContext<'a, 'mir, 'tcx, M> pub fn is_loop_detector_scheduled(&self) -> bool { /// The number of steps between loop detector snapshots. /// Should be a power of two for performance reasons. - const LOOP_SNAPSHOT_PERIOD: isize = 1 << 8; + const DETECTOR_SNAPSHOT_PERIOD: isize = 1 << 8; let steps = self.steps_until_detector_enabled; - steps <= 0 && steps % LOOP_SNAPSHOT_PERIOD == 0 + steps <= 0 && steps % DETECTOR_SNAPSHOT_PERIOD == 0 } pub fn inc_step_counter_and_detect_loops(&mut self, n: usize) -> EvalResult<'tcx, ()> {