shared mem opts, part 5

Summary:
Sig contexts have a bunch of fields that are not really needed for type checking
dependencies. Clearing out a few that are especially fat.

Reviewed By: samwgoldman

Differential Revision: D3935132

fbshipit-source-id: 4721c02b5afed0f16b1fe37ae013fdce6a5a6110

src/services/inference/merge_service.ml

@@ -168,6 +168,7 @@ let merge_strict_component ~options (component: filename list) =
     let cx = List.hd component_cxs in
     let errors = Context.errors cx in
     Context.remove_all_errors cx;
+    Context.clear_intermediates cx;
     Context_cache.add_sig ~audit:Expensive.ok cx;
     file, errors
   )

src/typing/context.ml

@@ -263,6 +263,11 @@ let set_type_graph cx type_graph =
 let set_tvar cx id node =
   cx.graph <- IMap.add id node cx.graph
 
+let clear_intermediates cx =
+  Hashtbl.clear cx.type_table;
+  Hashtbl.clear cx.annot_table;
+  cx.all_unresolved <- IMap.empty
+
 (* constructors *)
 let make_property_map cx pmap =
   let id = Reason.mk_id () in

src/typing/context.mli

@@ -116,5 +116,7 @@ val set_module_exports_type: t -> module_exports_type -> unit
 val set_property_maps: t -> Type.properties IMap.t -> unit
 val set_tvar: t -> Constraint.ident -> Constraint.node -> unit
 
+val clear_intermediates: t -> unit
+
 (* constructors *)
 val make_property_map: t -> Type.properties -> Constraint.ident