New upstream version 1.57.0+dfsg1

[rustc.git] / compiler / rustc_mir / src / borrow_check / type_check / liveness / polonius.rs

diff --git a/compiler/rustc_mir/src/borrow_check/type_check/liveness/polonius.rs b/compiler/rustc_mir/src/borrow_check/type_check/liveness/polonius.rs
deleted file mode 100644 (file)
index d285098..0000000
--- a/compiler/rustc_mir/src/borrow_check/type_check/liveness/polonius.rs
+++ /dev/null
@@ -1,141 +0,0 @@
-use crate::borrow_check::def_use::{self, DefUse};
-use crate::borrow_check::location::{LocationIndex, LocationTable};
-use crate::dataflow::indexes::MovePathIndex;
-use crate::dataflow::move_paths::{LookupResult, MoveData};
-use rustc_middle::mir::visit::{MutatingUseContext, PlaceContext, Visitor};
-use rustc_middle::mir::{Body, Local, Location, Place};
-use rustc_middle::ty::subst::GenericArg;
-
-use super::TypeChecker;
-
-type VarPointRelation = Vec<(Local, LocationIndex)>;
-type PathPointRelation = Vec<(MovePathIndex, LocationIndex)>;
-
-struct UseFactsExtractor<'me> {
-    var_defined_at: &'me mut VarPointRelation,
-    var_used_at: &'me mut VarPointRelation,
-    location_table: &'me LocationTable,
-    var_dropped_at: &'me mut VarPointRelation,
-    move_data: &'me MoveData<'me>,
-    path_accessed_at_base: &'me mut PathPointRelation,
-}
-
-// A Visitor to walk through the MIR and extract point-wise facts
-impl UseFactsExtractor<'_> {
-    fn location_to_index(&self, location: Location) -> LocationIndex {
-        self.location_table.mid_index(location)
-    }
-
-    fn insert_def(&mut self, local: Local, location: Location) {
-        debug!("UseFactsExtractor::insert_def()");
-        self.var_defined_at.push((local, self.location_to_index(location)));
-    }
-
-    fn insert_use(&mut self, local: Local, location: Location) {
-        debug!("UseFactsExtractor::insert_use()");
-        self.var_used_at.push((local, self.location_to_index(location)));
-    }
-
-    fn insert_drop_use(&mut self, local: Local, location: Location) {
-        debug!("UseFactsExtractor::insert_drop_use()");
-        self.var_dropped_at.push((local, self.location_to_index(location)));
-    }
-
-    fn insert_path_access(&mut self, path: MovePathIndex, location: Location) {
-        debug!("UseFactsExtractor::insert_path_access({:?}, {:?})", path, location);
-        self.path_accessed_at_base.push((path, self.location_to_index(location)));
-    }
-
-    fn place_to_mpi(&self, place: &Place<'_>) -> Option<MovePathIndex> {
-        match self.move_data.rev_lookup.find(place.as_ref()) {
-            LookupResult::Exact(mpi) => Some(mpi),
-            LookupResult::Parent(mmpi) => mmpi,
-        }
-    }
-}
-
-impl Visitor<'tcx> for UseFactsExtractor<'_> {
-    fn visit_local(&mut self, &local: &Local, context: PlaceContext, location: Location) {
-        match def_use::categorize(context) {
-            Some(DefUse::Def) => self.insert_def(local, location),
-            Some(DefUse::Use) => self.insert_use(local, location),
-            Some(DefUse::Drop) => self.insert_drop_use(local, location),
-            _ => (),
-        }
-    }
-
-    fn visit_place(&mut self, place: &Place<'tcx>, context: PlaceContext, location: Location) {
-        self.super_place(place, context, location);
-        match context {
-            PlaceContext::NonMutatingUse(_) => {
-                if let Some(mpi) = self.place_to_mpi(place) {
-                    self.insert_path_access(mpi, location);
-                }
-            }
-
-            PlaceContext::MutatingUse(MutatingUseContext::Borrow) => {
-                if let Some(mpi) = self.place_to_mpi(place) {
-                    self.insert_path_access(mpi, location);
-                }
-            }
-            _ => (),
-        }
-    }
-}
-
-pub(super) fn populate_access_facts(
-    typeck: &mut TypeChecker<'_, 'tcx>,
-    body: &Body<'tcx>,
-    location_table: &LocationTable,
-    move_data: &MoveData<'_>,
-    dropped_at: &mut Vec<(Local, Location)>,
-) {
-    debug!("populate_access_facts()");
-
-    if let Some(facts) = typeck.borrowck_context.all_facts.as_mut() {
-        let mut extractor = UseFactsExtractor {
-            var_defined_at: &mut facts.var_defined_at,
-            var_used_at: &mut facts.var_used_at,
-            var_dropped_at: &mut facts.var_dropped_at,
-            path_accessed_at_base: &mut facts.path_accessed_at_base,
-            location_table,
-            move_data,
-        };
-        extractor.visit_body(&body);
-
-        facts.var_dropped_at.extend(
-            dropped_at.iter().map(|&(local, location)| (local, location_table.mid_index(location))),
-        );
-
-        for (local, local_decl) in body.local_decls.iter_enumerated() {
-            debug!(
-                "add use_of_var_derefs_origin facts - local={:?}, type={:?}",
-                local, local_decl.ty
-            );
-            let _prof_timer = typeck.infcx.tcx.prof.generic_activity("polonius_fact_generation");
-            let universal_regions = &typeck.borrowck_context.universal_regions;
-            typeck.infcx.tcx.for_each_free_region(&local_decl.ty, |region| {
-                let region_vid = universal_regions.to_region_vid(region);
-                facts.use_of_var_derefs_origin.push((local, region_vid));
-            });
-        }
-    }
-}
-
-// For every potentially drop()-touched region `region` in `local`'s type
-// (`kind`), emit a Polonius `use_of_var_derefs_origin(local, origin)` fact.
-pub(super) fn add_drop_of_var_derefs_origin(
-    typeck: &mut TypeChecker<'_, 'tcx>,
-    local: Local,
-    kind: &GenericArg<'tcx>,
-) {
-    debug!("add_drop_of_var_derefs_origin(local={:?}, kind={:?}", local, kind);
-    if let Some(facts) = typeck.borrowck_context.all_facts.as_mut() {
-        let _prof_timer = typeck.infcx.tcx.prof.generic_activity("polonius_fact_generation");
-        let universal_regions = &typeck.borrowck_context.universal_regions;
-        typeck.infcx.tcx.for_each_free_region(kind, |drop_live_region| {
-            let region_vid = universal_regions.to_region_vid(drop_live_region);
-            facts.drop_of_var_derefs_origin.push((local, region_vid));
-        });
-    }
-}