feat(compiler): Add stack allocation information to small ints (#1780)

Author: ospencer

compiler/src/typed/builtin_types.re

@@ -281,12 +281,12 @@ let initial_env = (add_type, add_extension, empty_env) =>
   |> add_type(ident_result, decl_result)
   |> add_type(ident_list, decl_list)
   |> add_type(ident_range, decl_range)
-  |> add_type(ident_int8, decl_abstr(path_int8))
-  |> add_type(ident_int16, decl_abstr(path_int16))
+  |> add_type(ident_int8, decl_abstr_imm(WasmI32, path_int8))
+  |> add_type(ident_int16, decl_abstr_imm(WasmI32, path_int16))
   |> add_type(ident_int32, decl_abstr(path_int32))
   |> add_type(ident_int64, decl_abstr(path_int64))
-  |> add_type(ident_uint8, decl_abstr(path_uint8))
-  |> add_type(ident_uint16, decl_abstr(path_uint16))
+  |> add_type(ident_uint8, decl_abstr_imm(WasmI32, path_uint8))
+  |> add_type(ident_uint16, decl_abstr_imm(WasmI32, path_uint16))
   |> add_type(ident_uint32, decl_abstr(path_uint32))
   |> add_type(ident_uint64, decl_abstr(path_uint64))
   |> add_type(ident_float32, decl_abstr(path_float32))