Pass constraints to RegionInferenceContext::new.

Instead of destructuring it in advance and passing all the components
individually. It's less code that way.

Author: nnethercote

Diff for: compiler/rustc_borrowck/src/nll.rs

@@ -30,7 +30,7 @@ use crate::diagnostics::RegionErrors;
 use crate::facts::{AllFacts, AllFactsExt, RustcFacts};
 use crate::location::LocationTable;
 use crate::region_infer::RegionInferenceContext;
-use crate::type_check::{self, MirTypeckRegionConstraints, MirTypeckResults};
+use crate::type_check::{self, MirTypeckResults};
 use crate::universal_regions::UniversalRegions;
 use crate::{BorrowckInferCtxt, polonius, renumber};
 
@@ -117,15 +117,6 @@ pub(crate) fn compute_regions<'a, 'tcx>(
     // region inference data that was contained in `infcx`, and the
     // base constraints generated by the type-check.
     let var_origins = infcx.get_region_var_origins();
-    let MirTypeckRegionConstraints {
-        placeholder_indices,
-        placeholder_index_to_region: _,
-        liveness_constraints,
-        mut outlives_constraints,
-        mut member_constraints,
-        universe_causes,
-        type_tests,
-    } = constraints;
 
     // If requested, emit legacy polonius facts.
     polonius::emit_facts(
@@ -138,26 +129,11 @@ pub(crate) fn compute_regions<'a, 'tcx>(
         &universal_region_relations,
     );
 
-    if let Some(guar) = universal_region_relations.universal_regions.tainted_by_errors() {
-        // Suppress unhelpful extra errors in `infer_opaque_types` by clearing out all
-        // outlives bounds that we may end up checking.
-        outlives_constraints = Default::default();
-        member_constraints = Default::default();
-
-        // Also taint the entire scope.
-        infcx.set_tainted_by_errors(guar);
-    }
-
     let mut regioncx = RegionInferenceContext::new(
         infcx,
         var_origins,
-        placeholder_indices,
+        constraints,
         universal_region_relations,
-        outlives_constraints,
-        member_constraints,
-        universe_causes,
-        type_tests,
-        liveness_constraints,
         elements,
     );
 

Diff for: compiler/rustc_borrowck/src/region_infer/mod.rs

@@ -31,11 +31,9 @@ use crate::diagnostics::{RegionErrorKind, RegionErrors, UniverseInfo};
 use crate::member_constraints::{MemberConstraintSet, NllMemberConstraintIndex};
 use crate::nll::PoloniusOutput;
 use crate::region_infer::reverse_sccs::ReverseSccGraph;
-use crate::region_infer::values::{
-    LivenessValues, PlaceholderIndices, RegionElement, RegionValues, ToElementIndex,
-};
-use crate::type_check::Locations;
+use crate::region_infer::values::{LivenessValues, RegionElement, RegionValues, ToElementIndex};
 use crate::type_check::free_region_relations::UniversalRegionRelations;
+use crate::type_check::{Locations, MirTypeckRegionConstraints};
 use crate::universal_regions::UniversalRegions;
 
 mod dump_mir;
@@ -395,22 +393,36 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     pub(crate) fn new(
         infcx: &BorrowckInferCtxt<'tcx>,
         var_infos: VarInfos,
-        placeholder_indices: PlaceholderIndices,
+        constraints: MirTypeckRegionConstraints<'tcx>,
         universal_region_relations: Frozen<UniversalRegionRelations<'tcx>>,
-        mut outlives_constraints: OutlivesConstraintSet<'tcx>,
-        member_constraints_in: MemberConstraintSet<'tcx, RegionVid>,
-        universe_causes: FxIndexMap<ty::UniverseIndex, UniverseInfo<'tcx>>,
-        type_tests: Vec<TypeTest<'tcx>>,
-        liveness_constraints: LivenessValues,
         elements: Rc<DenseLocationMap>,
     ) -> Self {
         let universal_regions = &universal_region_relations.universal_regions;
+        let MirTypeckRegionConstraints {
+            placeholder_indices,
+            placeholder_index_to_region: _,
+            liveness_constraints,
+            mut outlives_constraints,
+            mut member_constraints,
+            universe_causes,
+            type_tests,
+        } = constraints;
 
         debug!("universal_regions: {:#?}", universal_region_relations.universal_regions);
         debug!("outlives constraints: {:#?}", outlives_constraints);
         debug!("placeholder_indices: {:#?}", placeholder_indices);
         debug!("type tests: {:#?}", type_tests);
 
+        if let Some(guar) = universal_region_relations.universal_regions.tainted_by_errors() {
+            // Suppress unhelpful extra errors in `infer_opaque_types` by clearing out all
+            // outlives bounds that we may end up checking.
+            outlives_constraints = Default::default();
+            member_constraints = Default::default();
+
+            // Also taint the entire scope.
+            infcx.set_tainted_by_errors(guar);
+        }
+
         // Create a RegionDefinition for each inference variable.
         let definitions: IndexVec<_, _> = var_infos
             .iter()
@@ -435,7 +447,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
         }
 
         let member_constraints =
-            Rc::new(member_constraints_in.into_mapped(|r| constraint_sccs.scc(r)));
+            Rc::new(member_constraints.into_mapped(|r| constraint_sccs.scc(r)));
 
         let mut result = Self {
             var_infos,