Remove ordering traits from HirId

Use indexmap where necessary to maintain ordering

Author: pierwill

Cargo.lock

@@ -3654,6 +3654,7 @@ name = "rustc_borrowck"
 version = "0.0.0"
 dependencies = [
  "either",
+ "indexmap",
  "itertools 0.9.0",
  "polonius-engine",
  "rustc_const_eval",
@@ -4568,6 +4569,7 @@ dependencies = [
 name = "rustc_typeck"
 version = "0.0.0"
 dependencies = [
+ "indexmap",
  "rustc_arena",
  "rustc_ast",
  "rustc_attr",

compiler/rustc_borrowck/Cargo.toml

@@ -28,3 +28,4 @@ rustc_target = { path = "../rustc_target" }
 rustc_trait_selection = { path = "../rustc_trait_selection" }
 rustc_traits = { path = "../rustc_traits" }
 rustc_span = { path = "../rustc_span" }
+indexmap = "1.7.0"

compiler/rustc_borrowck/src/constraints/mod.rs

@@ -13,7 +13,7 @@ crate mod graph;
 /// constraints of the form `R1: R2`. Each constraint is identified by
 /// a unique `OutlivesConstraintIndex` and you can index into the set
 /// (`constraint_set[i]`) to access the constraint details.
-#[derive(Clone, Default)]
+#[derive(Clone, Default, Hash)]
 crate struct OutlivesConstraintSet<'tcx> {
     outlives: IndexVec<OutlivesConstraintIndex, OutlivesConstraint<'tcx>>,
 }
@@ -72,7 +72,7 @@ impl<'tcx> Index<OutlivesConstraintIndex> for OutlivesConstraintSet<'tcx> {
     }
 }
 
-#[derive(Clone, PartialEq, Eq, PartialOrd, Ord)]
+#[derive(Clone, PartialEq, Eq, Hash)]
 pub struct OutlivesConstraint<'tcx> {
     // NB. The ordering here is not significant for correctness, but
     // it is for convenience. Before we dump the constraints in the

compiler/rustc_borrowck/src/region_infer/dump_mir.rs

@@ -71,8 +71,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
             }
         }
 
-        let mut constraints: Vec<_> = self.constraints.outlives().iter().collect();
-        constraints.sort();
+        let constraints: indexmap::IndexSet<_> = self.constraints.outlives().iter().collect();
         for constraint in &constraints {
             let OutlivesConstraint { sup, sub, locations, category, variance_info: _ } = constraint;
             let (name, arg) = match locations {

compiler/rustc_borrowck/src/region_infer/mod.rs

@@ -611,8 +611,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     #[instrument(skip(self, _body), level = "debug")]
     fn propagate_constraints(&mut self, _body: &Body<'tcx>) {
         debug!("constraints={:#?}", {
-            let mut constraints: Vec<_> = self.constraints.outlives().iter().collect();
-            constraints.sort();
+            let constraints: indexmap::IndexSet<_> = self.constraints.outlives().iter().collect();
             constraints
                 .into_iter()
                 .map(|c| (c, self.constraint_sccs.scc(c.sup), self.constraint_sccs.scc(c.sub)))
@@ -2006,7 +2005,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
             .unwrap_or_else(|| ObligationCauseCode::MiscObligation);
 
         // Classify each of the constraints along the path.
-        let mut categorized_path: Vec<BlameConstraint<'tcx>> = path
+        let mut categorized_path: indexmap::IndexSet<BlameConstraint<'tcx>> = path
             .iter()
             .map(|constraint| {
                 if constraint.category == ConstraintCategory::ClosureBounds {
@@ -2130,7 +2129,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
         );
 
         if let Some(i) = best_choice {
-            if let Some(next) = categorized_path.get(i + 1) {
+            if let Some(next) = categorized_path.get_index(i + 1) {
                 if matches!(categorized_path[i].category, ConstraintCategory::Return(_))
                     && next.category == ConstraintCategory::OpaqueType
                 {
@@ -2151,22 +2150,19 @@ impl<'tcx> RegionInferenceContext<'tcx> {
                 });
 
                 if let Some(field) = field {
-                    categorized_path[i].category =
+                    let mut blame_vec: Vec<_> = categorized_path.into_iter().collect();
+                    blame_vec[i].category =
                         ConstraintCategory::Return(ReturnConstraint::ClosureUpvar(field));
+                    let updated_categorized_path: indexmap::IndexSet<_> =
+                        blame_vec.into_iter().collect();
+                    categorized_path = updated_categorized_path
                 }
             }
 
             return categorized_path[i].clone();
         }
 
-        // If that search fails, that is.. unusual. Maybe everything
-        // is in the same SCC or something. In that case, find what
-        // appears to be the most interesting point to report to the
-        // user via an even more ad-hoc guess.
-        categorized_path.sort_by(|p0, p1| p0.category.cmp(&p1.category));
-        debug!("best_blame_constraint: sorted_path={:#?}", categorized_path);
-
-        categorized_path.remove(0)
+        categorized_path.shift_remove_index(0).unwrap()
     }
 
     crate fn universe_info(&self, universe: ty::UniverseIndex) -> UniverseInfo<'tcx> {
@@ -2266,7 +2262,7 @@ impl<'tcx> ClosureRegionRequirementsExt<'tcx> for ClosureRegionRequirements<'tcx
     }
 }
 
-#[derive(Clone, Debug)]
+#[derive(Clone, Debug, Hash, PartialEq, Eq)]
 pub struct BlameConstraint<'tcx> {
     pub category: ConstraintCategory,
     pub from_closure: bool,

compiler/rustc_hir/src/hir_id.rs

@@ -44,18 +44,6 @@ impl fmt::Display for HirId {
     }
 }
 
-impl Ord for HirId {
-    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
-        (self.index()).cmp(&(other.index()))
-    }
-}
-
-impl PartialOrd for HirId {
-    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
-        Some(self.cmp(&other))
-    }
-}
-
 rustc_data_structures::define_id_collections!(HirIdMap, HirIdSet, HirId);
 rustc_data_structures::define_id_collections!(ItemLocalMap, ItemLocalSet, ItemLocalId);
 

compiler/rustc_middle/src/mir/query.rs

@@ -318,7 +318,7 @@ rustc_data_structures::static_assert_size!(ConstraintCategory, 12);
 /// order of the category, thereby influencing diagnostic output.
 ///
 /// See also `rustc_const_eval::borrow_check::constraints`.
-#[derive(Copy, Clone, Debug, Eq, PartialEq, PartialOrd, Ord, Hash)]
+#[derive(Copy, Clone, Debug, Eq, PartialEq, Hash)]
 #[derive(TyEncodable, TyDecodable, HashStable)]
 pub enum ConstraintCategory {
     Return(ReturnConstraint),
@@ -358,7 +358,7 @@ pub enum ConstraintCategory {
     Internal,
 }
 
-#[derive(Copy, Clone, Debug, Eq, PartialEq, PartialOrd, Ord, Hash)]
+#[derive(Copy, Clone, Debug, Eq, PartialEq, Hash)]
 #[derive(TyEncodable, TyDecodable, HashStable)]
 pub enum ReturnConstraint {
     Normal,

compiler/rustc_middle/src/ty/sty.rs

@@ -2276,7 +2276,7 @@ impl<'tcx> TyS<'tcx> {
 /// a miscompilation or unsoundness.
 ///
 /// When in doubt, use `VarianceDiagInfo::default()`
-#[derive(Copy, Clone, Debug, Default, PartialEq, Eq, PartialOrd, Ord)]
+#[derive(Copy, Clone, Debug, Default, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub enum VarianceDiagInfo<'tcx> {
     /// No additional information - this is the default.
     /// We will not add any additional information to error messages.
@@ -2296,7 +2296,7 @@ pub enum VarianceDiagInfo<'tcx> {
     },
 }
 
-#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord)]
+#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub enum VarianceDiagMutKind {
     /// A mutable raw pointer (`*mut T`)
     RawPtr,

compiler/rustc_typeck/Cargo.toml

@@ -27,3 +27,4 @@ rustc_infer = { path = "../rustc_infer" }
 rustc_trait_selection = { path = "../rustc_trait_selection" }
 rustc_ty_utils = { path = "../rustc_ty_utils" }
 rustc_lint = { path = "../rustc_lint" }
+indexmap = "1.7.0"

compiler/rustc_typeck/src/check/upvar.rs

@@ -33,6 +33,7 @@
 use super::FnCtxt;
 
 use crate::expr_use_visitor as euv;
+use indexmap::IndexSet;
 use rustc_data_structures::fx::FxIndexMap;
 use rustc_errors::Applicability;
 use rustc_hir as hir;
@@ -86,7 +87,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 /// Intermediate format to store the hir_id pointing to the use that resulted in the
 /// corresponding place being captured and a String which contains the captured value's
 /// name (i.e: a.b.c)
-#[derive(Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
+#[derive(Clone, Debug, PartialEq, Eq, Hash)]
 enum UpvarMigrationInfo {
     /// We previously captured all of `x`, but now we capture some sub-path.
     CapturingPrecise { source_expr: Option<hir::HirId>, var_name: String },
@@ -1186,8 +1187,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 capture_diagnostic.insert(key.clone());
             }
 
-            let mut capture_diagnostic = capture_diagnostic.into_iter().collect::<Vec<_>>();
-            capture_diagnostic.sort();
+            let capture_diagnostic: IndexSet<_> = capture_diagnostic.into_iter().collect();
             for captures_info in capture_diagnostic {
                 // Get the auto trait reasons of why migration is needed because of that capture, if there are any
                 let capture_trait_reasons =