message: Pre-allocate local_map
diff: @@ -47,7 +47,7 @@ pub(crate) fn trans_fn<'clif, 'tcx, B: Backend + 'static>(
  bcx,
  block_map,
  - local_map: FxHashMap::default(),
  + local_map: FxHashMap::with_capacity_and_hasher(mir.local_decls.len(), Default::default()),
  caller_location: None, // set by `codegen_fn_prelude`
  cold_blocks: EntitySet::new(),
  