diff options
| -rw-r--r-- | src/librustc_mir/transform/generator.rs | 23 |
1 files changed, 12 insertions, 11 deletions
diff --git a/src/librustc_mir/transform/generator.rs b/src/librustc_mir/transform/generator.rs index 00caa06a6c0..24b77a7fdd6 100644 --- a/src/librustc_mir/transform/generator.rs +++ b/src/librustc_mir/transform/generator.rs @@ -467,12 +467,13 @@ fn locals_live_across_suspend_points( dataflow::ResultsCursor::new(body_ref, &requires_storage_results); // Calculate the liveness of MIR locals ignoring borrows. - let mut live_locals = liveness::LiveVarSet::new_empty(body.local_decls.len()); let mut liveness = liveness::liveness_of_locals(body); liveness::dump_mir(tcx, "generator_liveness", source, body_ref, &liveness); let mut storage_liveness_map = IndexVec::from_elem(None, body.basic_blocks()); let mut live_locals_at_suspension_points = Vec::new(); + let mut live_locals_at_any_suspension_point = + liveness::LiveVarSet::new_empty(body.local_decls.len()); for (block, data) in body.basic_blocks().iter_enumerated() { if let TerminatorKind::Yield { .. } = data.terminator().kind { @@ -509,39 +510,39 @@ fn locals_live_across_suspend_points( // Locals live are live at this point only if they are used across // suspension points (the `liveness` variable) // and their storage is required (the `storage_required` variable) - let mut live_locals_here = storage_required; - live_locals_here.intersect(&liveness.outs[block]); + let mut live_locals = storage_required; + live_locals.intersect(&liveness.outs[block]); // The generator argument is ignored. - live_locals_here.remove(SELF_ARG); + live_locals.remove(SELF_ARG); - debug!("loc = {:?}, live_locals_here = {:?}", loc, live_locals_here); + debug!("loc = {:?}, live_locals = {:?}", loc, live_locals); // Add the locals live at this suspension point to the set of locals which live across // any suspension points - live_locals.union(&live_locals_here); + live_locals_at_any_suspension_point.union(&live_locals); - live_locals_at_suspension_points.push(live_locals_here); + live_locals_at_suspension_points.push(live_locals); } } - debug!("live_locals = {:?}", live_locals); + debug!("live_locals_anywhere = {:?}", live_locals_at_any_suspension_point); // Renumber our liveness_map bitsets to include only the locals we are // saving. let live_locals_at_suspension_points = live_locals_at_suspension_points .iter() - .map(|live_here| renumber_bitset(&live_here, &live_locals)) + .map(|live_here| renumber_bitset(&live_here, &live_locals_at_any_suspension_point)) .collect(); let storage_conflicts = compute_storage_conflicts( body_ref, - &live_locals, + &live_locals_at_any_suspension_point, always_live_locals.clone(), requires_storage_results, ); LivenessInfo { - live_locals, + live_locals: live_locals_at_any_suspension_point, live_locals_at_suspension_points, storage_conflicts, storage_liveness: storage_liveness_map, |