Prime lang item queries

Author: Veykril

src/tools/rust-analyzer/crates/hir/src/lib.rs

@@ -133,7 +133,7 @@ pub use {
         attr::{AttrSourceMap, Attrs, AttrsWithOwner},
         find_path::PrefixKind,
         import_map,
-        lang_item::LangItem,
+        lang_item::{LangItem, crate_lang_items},
         nameres::{DefMap, ModuleSource, crate_def_map},
         per_ns::Namespace,
         type_ref::{Mutability, TypeRef},

src/tools/rust-analyzer/crates/ide-db/src/prime_caches.rs

@@ -83,7 +83,12 @@ pub fn parallel_prime_caches(
                         crate_name,
                     })?;
 
-                    let cancelled = Cancelled::catch(|| _ = hir::crate_def_map(&db, crate_id));
+                    let cancelled = Cancelled::catch(|| {
+                        _ = hir::crate_def_map(&db, crate_id);
+                        // we compute the lang items here as the work for them is also highly recursive and will be trigger by the module symbols query
+                        // slowing down leaf crate analysis tremendously as we go back to being blocked on a single thread
+                        _ = hir::crate_lang_items(&db, crate_id);
+                    });
 
                     match cancelled {
                         Ok(()) => progress_sender