diff options
Diffstat (limited to 'compiler/rustc_mir_dataflow/src/framework/direction.rs')
| -rw-r--r-- | compiler/rustc_mir_dataflow/src/framework/direction.rs | 130 |
1 files changed, 34 insertions, 96 deletions
diff --git a/compiler/rustc_mir_dataflow/src/framework/direction.rs b/compiler/rustc_mir_dataflow/src/framework/direction.rs index 9d943ebe327..45b1023e795 100644 --- a/compiler/rustc_mir_dataflow/src/framework/direction.rs +++ b/compiler/rustc_mir_dataflow/src/framework/direction.rs @@ -1,8 +1,6 @@ use std::ops::RangeInclusive; -use rustc_middle::mir::{ - self, BasicBlock, CallReturnPlaces, Location, SwitchTargets, TerminatorEdges, -}; +use rustc_middle::mir::{self, BasicBlock, CallReturnPlaces, Location, TerminatorEdges}; use super::visitor::ResultsVisitor; use super::{Analysis, Effect, EffectIndex, Results, SwitchIntTarget}; @@ -115,18 +113,18 @@ impl Direction for Backward { } mir::TerminatorKind::SwitchInt { targets: _, ref discr } => { - let mut applier = BackwardSwitchIntEdgeEffectsApplier { - body, - pred, - exit_state, - block, - propagate: &mut propagate, - effects_applied: false, - }; - - analysis.apply_switch_int_edge_effects(pred, discr, &mut applier); - - if !applier.effects_applied { + if let Some(mut data) = analysis.get_switch_int_data(block, discr) { + let values = &body.basic_blocks.switch_sources()[&(block, pred)]; + let targets = + values.iter().map(|&value| SwitchIntTarget { value, target: block }); + + let mut tmp = None; + for target in targets { + let tmp = opt_clone_from_or_clone(&mut tmp, exit_state); + analysis.apply_switch_int_edge_effect(&mut data, tmp, target); + propagate(pred, tmp); + } + } else { propagate(pred, exit_state) } } @@ -245,37 +243,6 @@ impl Direction for Backward { } } -struct BackwardSwitchIntEdgeEffectsApplier<'mir, 'tcx, D, F> { - body: &'mir mir::Body<'tcx>, - pred: BasicBlock, - exit_state: &'mir mut D, - block: BasicBlock, - propagate: &'mir mut F, - effects_applied: bool, -} - -impl<D, F> super::SwitchIntEdgeEffects<D> for BackwardSwitchIntEdgeEffectsApplier<'_, '_, D, F> -where - D: Clone, - F: FnMut(BasicBlock, &D), -{ - fn apply(&mut self, mut apply_edge_effect: impl FnMut(&mut D, SwitchIntTarget)) { - assert!(!self.effects_applied); - - let values = &self.body.basic_blocks.switch_sources()[&(self.block, self.pred)]; - let targets = values.iter().map(|&value| SwitchIntTarget { value, target: self.block }); - - let mut tmp = None; - for target in targets { - let tmp = opt_clone_from_or_clone(&mut tmp, self.exit_state); - apply_edge_effect(tmp, target); - (self.propagate)(self.pred, tmp); - } - - self.effects_applied = true; - } -} - /// Dataflow that runs from the entry of a block (the first statement), to its exit (terminator). pub struct Forward; @@ -324,23 +291,27 @@ impl Direction for Forward { } } TerminatorEdges::SwitchInt { targets, discr } => { - let mut applier = ForwardSwitchIntEdgeEffectsApplier { - exit_state, - targets, - propagate, - effects_applied: false, - }; - - analysis.apply_switch_int_edge_effects(block, discr, &mut applier); - - let ForwardSwitchIntEdgeEffectsApplier { - exit_state, - mut propagate, - effects_applied, - .. - } = applier; - - if !effects_applied { + if let Some(mut data) = analysis.get_switch_int_data(block, discr) { + let mut tmp = None; + for (value, target) in targets.iter() { + let tmp = opt_clone_from_or_clone(&mut tmp, exit_state); + analysis.apply_switch_int_edge_effect(&mut data, tmp, SwitchIntTarget { + value: Some(value), + target, + }); + propagate(target, tmp); + } + + // Once we get to the final, "otherwise" branch, there is no need to preserve + // `exit_state`, so pass it directly to `apply_switch_int_edge_effect` to save + // a clone of the dataflow state. + let otherwise = targets.otherwise(); + analysis.apply_switch_int_edge_effect(&mut data, exit_state, SwitchIntTarget { + value: None, + target: otherwise, + }); + propagate(otherwise, exit_state); + } else { for target in targets.all_targets() { propagate(*target, exit_state); } @@ -455,39 +426,6 @@ impl Direction for Forward { } } -struct ForwardSwitchIntEdgeEffectsApplier<'mir, D, F> { - exit_state: &'mir mut D, - targets: &'mir SwitchTargets, - propagate: F, - - effects_applied: bool, -} - -impl<D, F> super::SwitchIntEdgeEffects<D> for ForwardSwitchIntEdgeEffectsApplier<'_, D, F> -where - D: Clone, - F: FnMut(BasicBlock, &D), -{ - fn apply(&mut self, mut apply_edge_effect: impl FnMut(&mut D, SwitchIntTarget)) { - assert!(!self.effects_applied); - - let mut tmp = None; - for (value, target) in self.targets.iter() { - let tmp = opt_clone_from_or_clone(&mut tmp, self.exit_state); - apply_edge_effect(tmp, SwitchIntTarget { value: Some(value), target }); - (self.propagate)(target, tmp); - } - - // Once we get to the final, "otherwise" branch, there is no need to preserve `exit_state`, - // so pass it directly to `apply_edge_effect` to save a clone of the dataflow state. - let otherwise = self.targets.otherwise(); - apply_edge_effect(self.exit_state, SwitchIntTarget { value: None, target: otherwise }); - (self.propagate)(otherwise, self.exit_state); - - self.effects_applied = true; - } -} - /// An analogue of `Option::get_or_insert_with` that stores a clone of `val` into `opt`, but uses /// the more efficient `clone_from` if `opt` was `Some`. /// |