Auto merge of #102895 - Nilstrieb:query-cleanups, r=cjgillot

Get rid of `rustc_query_description!`

**I am not entirely sure whether this is an improvement and would like to get your feedback on it.**

Helps with #96524.

Queries can provide an arbitrary expression for their description and their caching behavior. Before, these expressions where stored in a `rustc_query_description` macro emitted by the `rustc_queries` macro, and then used in `rustc_query_impl` to fill out the methods for the `QueryDescription` trait.

Instead, we now emit two new modules from `rustc_queries` containing the functions with the expressions. `rustc_query_impl` calls these functions now instead of invoking the macro.

Since we are now defining some of the functions in `rustc_middle::query`, we now need all the imports for the key types mthere as well.

r? `@cjgillot`

2 files changed, 14 insertions, 2 deletions

diff --git a/compiler/rustc_middle/src/query/mod.rs b/compiler/rustc_middle/src/query/mod.rs
index 06eb10c9137..cfdc21ac234 100644
--- a/compiler/rustc_middle/src/query/mod.rs
+++ b/compiler/rustc_middle/src/query/mod.rs
@@ -4,6 +4,9 @@
 //! ["Queries: demand-driven compilation"](https://rustc-dev-guide.rust-lang.org/query.html).
 //! This chapter includes instructions for adding new queries.
 
+use crate::ty::{self, print::describe_as_module, TyCtxt};
+use rustc_span::def_id::LOCAL_CRATE;
+
 // Each of these queries corresponds to a function pointer field in the
 // `Providers` struct for requesting a value of that type, and a method
 // on `tcx: TyCtxt` (and `tcx.at(span)`) for doing that request in a way
@@ -1214,7 +1217,7 @@ rustc_queries! {
         desc { |tcx| "finding all vtable entries for trait {}", tcx.def_path_str(key.def_id()) }
     }
 
-    query vtable_trait_upcasting_coercion_new_vptr_slot(key: (ty::Ty<'tcx>, ty::Ty<'tcx>)) -> Option<usize> {
+    query vtable_trait_upcasting_coercion_new_vptr_slot(key: (Ty<'tcx>, Ty<'tcx>)) -> Option<usize> {
         desc { |tcx| "finding the slot within vtable for trait object {} vtable ptr during trait upcasting coercion from {} vtable",
             key.1, key.0 }
     }
diff --git a/compiler/rustc_middle/src/ty/print/mod.rs b/compiler/rustc_middle/src/ty/print/mod.rs
index e0a8d58f8a7..44b9548db89 100644
--- a/compiler/rustc_middle/src/ty/print/mod.rs
+++ b/compiler/rustc_middle/src/ty/print/mod.rs
@@ -3,7 +3,7 @@ use crate::ty::{self, DefIdTree, Ty, TyCtxt};
 
 use rustc_data_structures::fx::FxHashSet;
 use rustc_data_structures::sso::SsoHashSet;
-use rustc_hir::def_id::{CrateNum, DefId};
+use rustc_hir::def_id::{CrateNum, DefId, LocalDefId};
 use rustc_hir::definitions::{DefPathData, DisambiguatedDefPathData};
 
 // `pretty` is a separate module only for organization.
@@ -325,3 +325,12 @@ impl<'tcx, P: Printer<'tcx>> Print<'tcx, P> for ty::Const<'tcx> {
         cx.print_const(*self)
     }
 }
+
+// This is only used by query descriptions
+pub fn describe_as_module(def_id: LocalDefId, tcx: TyCtxt<'_>) -> String {
+    if def_id.is_top_level_module() {
+        "top-level module".to_string()
+    } else {
+        format!("module `{}`", tcx.def_path_str(def_id.to_def_id()))
+    }
+}