Mercurial > hg > graal-compiler
diff graal/com.oracle.max.base/src/com/sun/max/profile/Clock.java @ 3733:e233f5660da4
Added Java files from Maxine project.
author | Thomas Wuerthinger <thomas.wuerthinger@oracle.com> |
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date | Sat, 17 Dec 2011 19:59:18 +0100 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/graal/com.oracle.max.base/src/com/sun/max/profile/Clock.java Sat Dec 17 19:59:18 2011 +0100 @@ -0,0 +1,89 @@ +/* + * Copyright (c) 2007, 2011, 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. + */ +package com.sun.max.profile; + +/** + * The {@code Clock} class represents a clock source that has a continuously increasing tick + * count. A clock can be used to produce a relative timing between events by comparing the + * number of ticks between events. This can be used to implement time-based profiling + * by using a clock based on the system time. + */ +public abstract class Clock { + + public abstract long getTicks(); + + /** + * Gets the resolution of this clock as the number of {@linkplain #getTicks() ticks} per second. + * @return the resolution of the clock + */ + public abstract long getHZ(); + + public static final Clock SYSTEM_NANOSECONDS = new SystemNS(); + public static final Clock SYSTEM_MILLISECONDS = new SystemMS(); + + private static class SystemMS extends Clock { + @Override + public long getTicks() { + return System.currentTimeMillis(); + } + @Override + public long getHZ() { + return 1000; + } + } + + private static class SystemNS extends Clock { + @Override + public long getTicks() { + return System.nanoTime(); + } + @Override + public long getHZ() { + return 1000000000; + } + } + + public static int[] sampleDeltas(Clock clock, int numberOfSamples) { + final int[] result = new int[numberOfSamples]; + long sample = clock.getTicks(); + for (int i = 0; i < numberOfSamples; i++) { + final long newSample = clock.getTicks(); + result[i] = (int) (newSample - sample); + sample = newSample; + } + return result; + } + + public static void sample5(Clock clock, long[] samples) { + final long sample0 = clock.getTicks(); + final long sample1 = clock.getTicks(); + final long sample2 = clock.getTicks(); + final long sample3 = clock.getTicks(); + final long sample4 = clock.getTicks(); + samples[0] = sample0; + samples[1] = sample1; + samples[2] = sample2; + samples[3] = sample3; + samples[4] = sample4; + } +}