move QueryKeyStringCache from rustc_middle to rustc_query_impl, where it actually used

also allows to drop measureme dep on rustc_middle

Cargo.lock

@@ -4263,7 +4263,6 @@ dependencies = [
  "either",
  "field-offset",
  "gsgdt",
- "measureme",
  "polonius-engine",
  "rustc-rayon",
  "rustc-rayon-core",

compiler/rustc_middle/Cargo.toml

@@ -10,7 +10,6 @@ derivative = "2.2.0"
 either = "1.5.0"
 field-offset = "0.3.5"
 gsgdt = "0.1.2"
-measureme = "11"
 polonius-engine = "0.13.0"
 rustc-rayon = { version = "0.5.0", optional = true }
 rustc-rayon-core = { version = "0.5.0", optional = true }

compiler/rustc_middle/src/query/plumbing.rs

@@ -8,8 +8,6 @@
 };
 use crate::ty::TyCtxt;
 use field_offset::FieldOffset;
-use measureme::StringId;
-use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sync::AtomicU64;
 use rustc_data_structures::sync::WorkerLocal;
 use rustc_hir::def_id::{DefId, LocalDefId};
@@ -22,16 +20,6 @@
 use rustc_span::{ErrorGuaranteed, Span, DUMMY_SP};
 use std::ops::Deref;
 
-pub struct QueryKeyStringCache {
-    pub def_id_cache: FxHashMap<DefId, StringId>,
-}
-
-impl QueryKeyStringCache {
-    pub fn new() -> QueryKeyStringCache {
-        QueryKeyStringCache { def_id_cache: Default::default() }
-    }
-}
-
 pub struct DynamicQuery<'tcx, C: QueryCache> {
     pub name: &'static str,
     pub eval_always: bool,

compiler/rustc_query_impl/src/lib.rs

@@ -13,6 +13,7 @@
 extern crate rustc_middle;
 
 use crate::plumbing::{__rust_begin_short_backtrace, encode_all_query_results, try_mark_green};
+use crate::profiling_support::QueryKeyStringCache;
 use field_offset::offset_of;
 use rustc_data_structures::stable_hasher::HashStable;
 use rustc_data_structures::sync::AtomicU64;
@@ -21,9 +22,7 @@
 use rustc_middle::dep_graph::{self, DepKind, DepKindStruct};
 use rustc_middle::query::erase::{erase, restore, Erase};
 use rustc_middle::query::on_disk_cache::{CacheEncoder, EncodedDepNodeIndex, OnDiskCache};
-use rustc_middle::query::plumbing::{
-    DynamicQuery, QueryKeyStringCache, QuerySystem, QuerySystemFns,
-};
+use rustc_middle::query::plumbing::{DynamicQuery, QuerySystem, QuerySystemFns};
 use rustc_middle::query::AsLocalKey;
 use rustc_middle::query::{
     queries, DynamicQueries, ExternProviders, Providers, QueryCaches, QueryEngine, QueryStates,

compiler/rustc_query_impl/src/profiling_support.rs

@@ -1,13 +1,23 @@
 use measureme::{StringComponent, StringId};
+use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::profiling::SelfProfiler;
 use rustc_hir::def_id::{CrateNum, DefId, DefIndex, LocalDefId, LOCAL_CRATE};
 use rustc_hir::definitions::DefPathData;
-use rustc_middle::query::plumbing::QueryKeyStringCache;
 use rustc_middle::ty::TyCtxt;
 use rustc_query_system::query::QueryCache;
 use std::fmt::Debug;
 use std::io::Write;
 
+pub(crate) struct QueryKeyStringCache {
+    def_id_cache: FxHashMap<DefId, StringId>,
+}
+
+impl QueryKeyStringCache {
+    fn new() -> QueryKeyStringCache {
+        QueryKeyStringCache { def_id_cache: Default::default() }
+    }
+}
+
 struct QueryKeyStringBuilder<'p, 'tcx> {
     profiler: &'p SelfProfiler,
     tcx: TyCtxt<'tcx>,