/*

 * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#include "precompiled.hpp"

#include "runtime/os.hpp"

#include "utilities/ticks.inline.hpp"

#ifdef ASSERT

 const jlong Ticks::invalid_time_stamp = -2; // 0xFFFF FFFF`FFFF FFFE

#endif

void Ticks::stamp() {

  _stamp_ticks = os::elapsed_counter();

}

const Ticks Ticks::now() {

  Ticks t;

  t.stamp();

  return t;

}

Tickspan::Tickspan(const Ticks& end, const Ticks& start) {

  assert(end.value() != Ticks::invalid_time_stamp, "end is unstamped!");

  assert(start.value() != Ticks::invalid_time_stamp, "start is unstamped!");

  assert(end >= start, "negative time!");

  _span_ticks = end.value() - start.value();

}

template <typename ReturnType>

static ReturnType time_conversion(const Tickspan& span, TicksToTimeHelper::Unit unit) {

  assert(TicksToTimeHelper::SECONDS == unit ||

         TicksToTimeHelper::MILLISECONDS == unit, "invalid unit!");

  ReturnType frequency_per_unit = (ReturnType)os::elapsed_frequency() / (ReturnType)unit;

  return (ReturnType) ((ReturnType)span.value() / frequency_per_unit);

}

double TicksToTimeHelper::seconds(const Tickspan& span) {

  return time_conversion<double>(span, SECONDS);

}

jlong TicksToTimeHelper::milliseconds(const Tickspan& span) {

  return time_conversion<jlong>(span, MILLISECONDS);

}