Merge #3584

3584: Switch to dynamic dispatch r=matklad a=matklad

Benches are in https://github.com/rust-analyzer/rust-analyzer/issues/1987#issuecomment-598807185

TL;DR: 

* 33% faster release build
* slightly worse/same perf
* no changes for debug build
* slightly smaller binary

cc @flodiebold I genuinely don't know if it is a good idea or not.

Co-authored-by: Aleksey Kladov <[email protected]>

1 files changed, 2 insertions, 2 deletions

diff --git a/crates/ra_hir_ty/src/db.rs b/crates/ra_hir_ty/src/db.rs
index 74b309005..11fc2ac3d 100644
--- a/crates/ra_hir_ty/src/db.rs
+++ b/crates/ra_hir_ty/src/db.rs
@@ -7,7 +7,7 @@ use hir_def::{
     VariantId,
 };
 use ra_arena::map::ArenaMap;
-use ra_db::{impl_intern_key, salsa, CrateId};
+use ra_db::{impl_intern_key, salsa, CrateId, Upcast};
 use ra_prof::profile;
 
 use crate::{
@@ -20,7 +20,7 @@ use hir_expand::name::Name;
 
 #[salsa::query_group(HirDatabaseStorage)]
 #[salsa::requires(salsa::Database)]
-pub trait HirDatabase: DefDatabase {
+pub trait HirDatabase: DefDatabase + Upcast<dyn DefDatabase> {
     #[salsa::invoke(infer_wait)]
     fn infer(&self, def: DefWithBodyId) -> Arc<InferenceResult>;