diff options
Diffstat (limited to 'compiler/rustc_mir_dataflow/src/framework/cursor.rs')
-rw-r--r-- | compiler/rustc_mir_dataflow/src/framework/cursor.rs | 112 |
1 files changed, 97 insertions, 15 deletions
diff --git a/compiler/rustc_mir_dataflow/src/framework/cursor.rs b/compiler/rustc_mir_dataflow/src/framework/cursor.rs index f3b5544aa..c978bddfe 100644 --- a/compiler/rustc_mir_dataflow/src/framework/cursor.rs +++ b/compiler/rustc_mir_dataflow/src/framework/cursor.rs @@ -1,18 +1,60 @@ //! Random access inspection of the results of a dataflow analysis. -use crate::framework::BitSetExt; +use crate::{framework::BitSetExt, CloneAnalysis}; -use std::borrow::Borrow; +use std::borrow::{Borrow, BorrowMut}; use std::cmp::Ordering; #[cfg(debug_assertions)] use rustc_index::bit_set::BitSet; use rustc_middle::mir::{self, BasicBlock, Location}; -use super::{Analysis, Direction, Effect, EffectIndex, Results}; +use super::{Analysis, Direction, Effect, EffectIndex, EntrySets, Results, ResultsCloned}; + +// `AnalysisResults` is needed as an impl such as the following has an unconstrained type +// parameter: +// ``` +// impl<'tcx, A, E, R> ResultsCursor<'_, 'tcx, A, R> +// where +// A: Analysis<'tcx>, +// E: Borrow<EntrySets<'tcx, A>>, +// R: Results<'tcx, A, E>, +// {} +// ``` + +/// A type representing the analysis results consumed by a `ResultsCursor`. +pub trait AnalysisResults<'tcx, A>: BorrowMut<Results<'tcx, A, Self::EntrySets>> +where + A: Analysis<'tcx>, +{ + /// The type containing the entry sets for this `Results` type. + /// + /// Should be either `EntrySets<'tcx, A>` or `&EntrySets<'tcx, A>`. + type EntrySets: Borrow<EntrySets<'tcx, A>>; +} +impl<'tcx, A, E> AnalysisResults<'tcx, A> for Results<'tcx, A, E> +where + A: Analysis<'tcx>, + E: Borrow<EntrySets<'tcx, A>>, +{ + type EntrySets = E; +} +impl<'a, 'tcx, A, E> AnalysisResults<'tcx, A> for &'a mut Results<'tcx, A, E> +where + A: Analysis<'tcx>, + E: Borrow<EntrySets<'tcx, A>>, +{ + type EntrySets = E; +} /// A `ResultsCursor` that borrows the underlying `Results`. -pub type ResultsRefCursor<'a, 'mir, 'tcx, A> = ResultsCursor<'mir, 'tcx, A, &'a Results<'tcx, A>>; +pub type ResultsRefCursor<'res, 'mir, 'tcx, A> = + ResultsCursor<'mir, 'tcx, A, &'res mut Results<'tcx, A>>; + +/// A `ResultsCursor` which uses a cloned `Analysis` while borrowing the underlying `Results`. This +/// allows multiple cursors over the same `Results`. +pub type ResultsClonedCursor<'res, 'mir, 'tcx, A> = + ResultsCursor<'mir, 'tcx, A, ResultsCloned<'res, 'tcx, A>>; /// Allows random access inspection of the results of a dataflow analysis. /// @@ -45,7 +87,38 @@ where impl<'mir, 'tcx, A, R> ResultsCursor<'mir, 'tcx, A, R> where A: Analysis<'tcx>, - R: Borrow<Results<'tcx, A>>, +{ + /// Returns the dataflow state at the current location. + pub fn get(&self) -> &A::Domain { + &self.state + } + + /// Returns the body this analysis was run on. + pub fn body(&self) -> &'mir mir::Body<'tcx> { + self.body + } + + /// Unwraps this cursor, returning the underlying `Results`. + pub fn into_results(self) -> R { + self.results + } +} + +impl<'res, 'mir, 'tcx, A> ResultsCursor<'mir, 'tcx, A, ResultsCloned<'res, 'tcx, A>> +where + A: Analysis<'tcx> + CloneAnalysis, +{ + /// Creates a new cursor over the same `Results`. Note that the cursor's position is *not* + /// copied. + pub fn new_cursor(&self) -> Self { + Self::new(self.body, self.results.reclone_analysis()) + } +} + +impl<'mir, 'tcx, A, R> ResultsCursor<'mir, 'tcx, A, R> +where + A: Analysis<'tcx>, + R: AnalysisResults<'tcx, A>, { /// Returns a new cursor that can inspect `results`. pub fn new(body: &'mir mir::Body<'tcx>, results: R) -> Self { @@ -74,8 +147,13 @@ where } /// Returns the underlying `Results`. - pub fn results(&self) -> &Results<'tcx, A> { - &self.results.borrow() + pub fn results(&mut self) -> &Results<'tcx, A, R::EntrySets> { + self.results.borrow() + } + + /// Returns the underlying `Results`. + pub fn mut_results(&mut self) -> &mut Results<'tcx, A, R::EntrySets> { + self.results.borrow_mut() } /// Returns the `Analysis` used to generate the underlying `Results`. @@ -83,9 +161,14 @@ where &self.results.borrow().analysis } - /// Returns the dataflow state at the current location. - pub fn get(&self) -> &A::Domain { - &self.state + /// Returns the `Analysis` used to generate the underlying `Results`. + pub fn mut_analysis(&mut self) -> &mut A { + &mut self.results.borrow_mut().analysis + } + + /// Returns both the dataflow state at the current location and the `Analysis`. + pub fn get_with_analysis(&mut self) -> (&A::Domain, &mut A) { + (&self.state, &mut self.results.borrow_mut().analysis) } /// Resets the cursor to hold the entry set for the given basic block. @@ -97,7 +180,7 @@ where #[cfg(debug_assertions)] assert!(self.reachable_blocks.contains(block)); - self.state.clone_from(&self.results.borrow().entry_set_for_block(block)); + self.state.clone_from(self.results.borrow().entry_set_for_block(block)); self.pos = CursorPosition::block_entry(block); self.state_needs_reset = false; } @@ -186,7 +269,7 @@ where ) }; - let analysis = &self.results.borrow().analysis; + let analysis = &mut self.results.borrow_mut().analysis; let target_effect_index = effect.at_index(target.statement_index); A::Direction::apply_effects_in_range( @@ -205,8 +288,8 @@ where /// /// This can be used, e.g., to apply the call return effect directly to the cursor without /// creating an extra copy of the dataflow state. - pub fn apply_custom_effect(&mut self, f: impl FnOnce(&A, &mut A::Domain)) { - f(&self.results.borrow().analysis, &mut self.state); + pub fn apply_custom_effect(&mut self, f: impl FnOnce(&mut A, &mut A::Domain)) { + f(&mut self.results.borrow_mut().analysis, &mut self.state); self.state_needs_reset = true; } } @@ -215,7 +298,6 @@ impl<'mir, 'tcx, A, R> ResultsCursor<'mir, 'tcx, A, R> where A: crate::GenKillAnalysis<'tcx>, A::Domain: BitSetExt<A::Idx>, - R: Borrow<Results<'tcx, A>>, { pub fn contains(&self, elem: A::Idx) -> bool { self.get().contains(elem) |