in src/main/scala/kotlin/AnalyzingKotlinCompiler.scala [237:243]
private[this] def timed[T](label: String, log: Logger)(t: => T): T = {
val start = System.nanoTime
val result = t
val elapsed = System.nanoTime - start
log.debug(label + " took " + (elapsed / 1e9) + " s")
result
}