type 'a by_copying_function_body = env:Inline_and_simplify_aux.Env.t -> r:Inline_and_simplify_aux.Result.t -> clos:Flambda.function_declarations -> lfunc:Flambda.t -> fun_id:Closure_id.t -> func:Flambda.function_declaration -> args:Flambda.t list -> Flambda.t * Inline_and_simplify_aux.Result.t
type 'a by_copying_function_declaration = env:Inline_and_simplify_aux.Env.t -> r:Inline_and_simplify_aux.Result.t -> funct:Flambda.t -> clos:Flambda.function_declarations -> fun_id:Closure_id.t -> func:Flambda.function_declaration -> args_with_approxs:(Flambda.t list * Simple_value_approx.t list) -> invariant_params:Variable.Set.t -> specialised_args:Variable.Set.t -> dbg:Debuginfo.t -> (Flambda.t * Inline_and_simplify_aux.Result.t) option