println!("[{:<30}: {}] start", tcx.crate_name(LOCAL_CRATE), name);
let before = std::time::Instant::now();
let res = tcx.sess.time(name, f);
let after = std::time::Instant::now();
println!("[{:<30}: {}] start", tcx.crate_name(LOCAL_CRATE), name);
let before = std::time::Instant::now();
let res = tcx.sess.time(name, f);
let after = std::time::Instant::now();