Introduce UnordMap, UnordSet, and UnordBag (see MCP 533)

MCP 533: https://github.com/rust-lang/compiler-team/issues/533

Also, as an example, substitute UnordMap for FxHashMap in
used_trait_imports query result.

1 files changed, 3 insertions, 2 deletions

diff --git a/compiler/rustc_query_impl/src/on_disk_cache.rs b/compiler/rustc_query_impl/src/on_disk_cache.rs
index a5921650112..8b14ce210a2 100644
--- a/compiler/rustc_query_impl/src/on_disk_cache.rs
+++ b/compiler/rustc_query_impl/src/on_disk_cache.rs
@@ -1,8 +1,9 @@
 use crate::QueryCtxt;
-use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexSet};
+use rustc_data_structures::fx::{FxHashMap, FxIndexSet};
 use rustc_data_structures::memmap::Mmap;
 use rustc_data_structures::sync::{HashMapExt, Lock, Lrc, RwLock};
 use rustc_data_structures::unhash::UnhashMap;
+use rustc_data_structures::unord::UnordSet;
 use rustc_hir::def_id::{CrateNum, DefId, DefIndex, LocalDefId, StableCrateId, LOCAL_CRATE};
 use rustc_hir::definitions::DefPathHash;
 use rustc_index::vec::{Idx, IndexVec};
@@ -792,7 +793,7 @@ impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for DefId {
     }
 }
 
-impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for &'tcx FxHashSet<LocalDefId> {
+impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for &'tcx UnordSet<LocalDefId> {
     fn decode(d: &mut CacheDecoder<'a, 'tcx>) -> Self {
         RefDecodable::decode(d)
     }