diff options
Diffstat (limited to 'compiler/rustc_borrowck/src/nll.rs')
| -rw-r--r-- | compiler/rustc_borrowck/src/nll.rs | 207 |
1 files changed, 40 insertions, 167 deletions
diff --git a/compiler/rustc_borrowck/src/nll.rs b/compiler/rustc_borrowck/src/nll.rs index 0ea4401a8..6781c6a75 100644 --- a/compiler/rustc_borrowck/src/nll.rs +++ b/compiler/rustc_borrowck/src/nll.rs @@ -2,16 +2,17 @@ #![deny(rustc::diagnostic_outside_of_impl)] //! The entry point of the NLL borrow checker. +use polonius_engine::{Algorithm, Output}; use rustc_data_structures::fx::FxIndexMap; use rustc_hir::def_id::LocalDefId; use rustc_index::IndexSlice; use rustc_middle::mir::{create_dump_file, dump_enabled, dump_mir, PassWhere}; -use rustc_middle::mir::{ - Body, ClosureOutlivesSubject, ClosureRegionRequirements, LocalKind, Location, Promoted, - START_BLOCK, -}; +use rustc_middle::mir::{Body, ClosureOutlivesSubject, ClosureRegionRequirements, Promoted}; use rustc_middle::ty::print::with_no_trimmed_paths; use rustc_middle::ty::{self, OpaqueHiddenType, TyCtxt}; +use rustc_mir_dataflow::impls::MaybeInitializedPlaces; +use rustc_mir_dataflow::move_paths::MoveData; +use rustc_mir_dataflow::ResultsCursor; use rustc_span::symbol::sym; use std::env; use std::io; @@ -19,25 +20,18 @@ use std::path::PathBuf; use std::rc::Rc; use std::str::FromStr; -use polonius_engine::{Algorithm, Output}; - -use rustc_mir_dataflow::impls::MaybeInitializedPlaces; -use rustc_mir_dataflow::move_paths::{InitKind, InitLocation, MoveData}; -use rustc_mir_dataflow::ResultsCursor; - use crate::{ borrow_set::BorrowSet, - constraint_generation, consumers::ConsumerOptions, diagnostics::RegionErrors, facts::{AllFacts, AllFactsExt, RustcFacts}, - invalidation, location::LocationTable, + polonius, region_infer::{values::RegionValueElements, RegionInferenceContext}, renumber, type_check::{self, MirTypeckRegionConstraints, MirTypeckResults}, universal_regions::UniversalRegions, - BorrowckInferCtxt, Upvar, + BorrowckInferCtxt, }; pub type PoloniusOutput = Output<RustcFacts>; @@ -78,81 +72,6 @@ pub(crate) fn replace_regions_in_mir<'tcx>( universal_regions } -// This function populates an AllFacts instance with base facts related to -// MovePaths and needed for the move analysis. -fn populate_polonius_move_facts( - all_facts: &mut AllFacts, - move_data: &MoveData<'_>, - location_table: &LocationTable, - body: &Body<'_>, -) { - all_facts - .path_is_var - .extend(move_data.rev_lookup.iter_locals_enumerated().map(|(l, r)| (r, l))); - - for (child, move_path) in move_data.move_paths.iter_enumerated() { - if let Some(parent) = move_path.parent { - all_facts.child_path.push((child, parent)); - } - } - - let fn_entry_start = - location_table.start_index(Location { block: START_BLOCK, statement_index: 0 }); - - // initialized_at - for init in move_data.inits.iter() { - match init.location { - InitLocation::Statement(location) => { - let block_data = &body[location.block]; - let is_terminator = location.statement_index == block_data.statements.len(); - - if is_terminator && init.kind == InitKind::NonPanicPathOnly { - // We are at the terminator of an init that has a panic path, - // and where the init should not happen on panic - - for successor in block_data.terminator().successors() { - if body[successor].is_cleanup { - continue; - } - - // The initialization happened in (or rather, when arriving at) - // the successors, but not in the unwind block. - let first_statement = Location { block: successor, statement_index: 0 }; - all_facts - .path_assigned_at_base - .push((init.path, location_table.start_index(first_statement))); - } - } else { - // In all other cases, the initialization just happens at the - // midpoint, like any other effect. - all_facts - .path_assigned_at_base - .push((init.path, location_table.mid_index(location))); - } - } - // Arguments are initialized on function entry - InitLocation::Argument(local) => { - assert!(body.local_kind(local) == LocalKind::Arg); - all_facts.path_assigned_at_base.push((init.path, fn_entry_start)); - } - } - } - - for (local, path) in move_data.rev_lookup.iter_locals_enumerated() { - if body.local_kind(local) != LocalKind::Arg { - // Non-arguments start out deinitialised; we simulate this with an - // initial move: - all_facts.path_moved_at_base.push((path, fn_entry_start)); - } - } - - // moved_out_at - // deinitialisation is assumed to always happen! - all_facts - .path_moved_at_base - .extend(move_data.moves.iter().map(|mo| (mo.path, location_table.mid_index(mo.source)))); -} - /// Computes the (non-lexical) regions from the input MIR. /// /// This may result in errors being reported. @@ -166,7 +85,7 @@ pub(crate) fn compute_regions<'cx, 'tcx>( flow_inits: &mut ResultsCursor<'cx, 'tcx, MaybeInitializedPlaces<'cx, 'tcx>>, move_data: &MoveData<'tcx>, borrow_set: &BorrowSet<'tcx>, - upvars: &[Upvar<'tcx>], + upvars: &[&ty::CapturedPlace<'tcx>], consumer_options: Option<ConsumerOptions>, ) -> NllOutput<'tcx> { let is_polonius_legacy_enabled = infcx.tcx.sess.opts.unstable_opts.polonius.is_legacy_enabled(); @@ -179,70 +98,26 @@ pub(crate) fn compute_regions<'cx, 'tcx>( let universal_regions = Rc::new(universal_regions); - let elements = &Rc::new(RegionValueElements::new(&body)); + let elements = &Rc::new(RegionValueElements::new(body)); // Run the MIR type-checker. - let MirTypeckResults { - constraints, - universal_region_relations, - opaque_type_values, - live_loans, - } = type_check::type_check( - infcx, - param_env, - body, - promoted, - &universal_regions, - location_table, - borrow_set, - &mut all_facts, - flow_inits, - move_data, - elements, - upvars, - polonius_input, - ); - - if let Some(all_facts) = &mut all_facts { - let _prof_timer = infcx.tcx.prof.generic_activity("polonius_fact_generation"); - all_facts.universal_region.extend(universal_regions.universal_regions()); - populate_polonius_move_facts(all_facts, move_data, location_table, &body); - - // Emit universal regions facts, and their relations, for Polonius. - // - // 1: universal regions are modeled in Polonius as a pair: - // - the universal region vid itself. - // - a "placeholder loan" associated to this universal region. Since they don't exist in - // the `borrow_set`, their `BorrowIndex` are synthesized as the universal region index - // added to the existing number of loans, as if they succeeded them in the set. - // - let borrow_count = borrow_set.len(); - debug!( - "compute_regions: polonius placeholders, num_universals={}, borrow_count={}", - universal_regions.len(), - borrow_count + let MirTypeckResults { constraints, universal_region_relations, opaque_type_values } = + type_check::type_check( + infcx, + param_env, + body, + promoted, + &universal_regions, + location_table, + borrow_set, + &mut all_facts, + flow_inits, + move_data, + elements, + upvars, + polonius_input, ); - for universal_region in universal_regions.universal_regions() { - let universal_region_idx = universal_region.index(); - let placeholder_loan_idx = borrow_count + universal_region_idx; - all_facts.placeholder.push((universal_region, placeholder_loan_idx.into())); - } - - // 2: the universal region relations `outlives` constraints are emitted as - // `known_placeholder_subset` facts. - for (fr1, fr2) in universal_region_relations.known_outlives() { - if fr1 != fr2 { - debug!( - "compute_regions: emitting polonius `known_placeholder_subset` \ - fr1={:?}, fr2={:?}", - fr1, fr2 - ); - all_facts.known_placeholder_subset.push((fr1, fr2)); - } - } - } - // Create the region inference context, taking ownership of the // region inference data that was contained in `infcx`, and the // base constraints generated by the type-check. @@ -250,7 +125,7 @@ pub(crate) fn compute_regions<'cx, 'tcx>( let MirTypeckRegionConstraints { placeholder_indices, placeholder_index_to_region: _, - mut liveness_constraints, + liveness_constraints, outlives_constraints, member_constraints, universe_causes, @@ -258,13 +133,16 @@ pub(crate) fn compute_regions<'cx, 'tcx>( } = constraints; let placeholder_indices = Rc::new(placeholder_indices); - constraint_generation::generate_constraints( - infcx, - &mut liveness_constraints, + // If requested, emit legacy polonius facts. + polonius::emit_facts( &mut all_facts, + infcx.tcx, location_table, - &body, + body, borrow_set, + move_data, + &universal_regions, + &universal_region_relations, ); let mut regioncx = RegionInferenceContext::new( @@ -279,17 +157,12 @@ pub(crate) fn compute_regions<'cx, 'tcx>( type_tests, liveness_constraints, elements, - live_loans, ); - // Generate various additional constraints. - invalidation::generate_invalidates(infcx.tcx, &mut all_facts, location_table, body, borrow_set); - - let def_id = body.source.def_id(); - - // Dump facts if requested. + // If requested: dump NLL facts, and run legacy polonius analysis. let polonius_output = all_facts.as_ref().and_then(|all_facts| { if infcx.tcx.sess.opts.unstable_opts.nll_facts { + let def_id = body.source.def_id(); let def_path = infcx.tcx.def_path(def_id); let dir_path = PathBuf::from(&infcx.tcx.sess.opts.unstable_opts.nll_facts_dir) .join(def_path.to_filename_friendly_no_crate()); @@ -302,7 +175,7 @@ pub(crate) fn compute_regions<'cx, 'tcx>( let algorithm = Algorithm::from_str(&algorithm).unwrap(); debug!("compute_regions: using polonius algorithm {:?}", algorithm); let _prof_timer = infcx.tcx.prof.generic_activity("polonius_analysis"); - Some(Rc::new(Output::compute(&all_facts, algorithm, false))) + Some(Rc::new(Output::compute(all_facts, algorithm, false))) } else { None } @@ -310,17 +183,17 @@ pub(crate) fn compute_regions<'cx, 'tcx>( // Solve the region constraints. let (closure_region_requirements, nll_errors) = - regioncx.solve(infcx, param_env, &body, polonius_output.clone()); + regioncx.solve(infcx, param_env, body, polonius_output.clone()); if !nll_errors.is_empty() { // Suppress unhelpful extra errors in `infer_opaque_types`. - infcx.set_tainted_by_errors(infcx.tcx.sess.delay_span_bug( + infcx.set_tainted_by_errors(infcx.tcx.sess.span_delayed_bug( body.span, "`compute_regions` tainted `infcx` with errors but did not emit any errors", )); } - let remapped_opaque_tys = regioncx.infer_opaque_types(&infcx, opaque_type_values); + let remapped_opaque_tys = regioncx.infer_opaque_types(infcx, opaque_type_values); NllOutput { regioncx, @@ -407,7 +280,7 @@ pub(super) fn dump_annotation<'tcx>( let def_span = tcx.def_span(body.source.def_id()); let mut err = if let Some(closure_region_requirements) = closure_region_requirements { - let mut err = tcx.sess.diagnostic().span_note_diag(def_span, "external requirements"); + let mut err = tcx.sess.dcx().struct_span_note(def_span, "external requirements"); regioncx.annotate(tcx, &mut err); @@ -426,7 +299,7 @@ pub(super) fn dump_annotation<'tcx>( err } else { - let mut err = tcx.sess.diagnostic().span_note_diag(def_span, "no external requirements"); + let mut err = tcx.sess.dcx().struct_span_note(def_span, "no external requirements"); regioncx.annotate(tcx, &mut err); err |