test/loops/LoopHelpers.java

/*
 * Written by Doug Lea with assistance from members of JCP JSR-166
 * Expert Group and released to the public domain, as explained at
 * http://creativecommons.org/publicdomain/zero/1.0/
 */

import java.util.concurrent.*;
import java.util.concurrent.atomic.*;

/**
 * Misc utilities in JSR166 performance tests
 */
class LoopHelpers {

    static final SimpleRandom staticRNG = new SimpleRandom();

    // Some mindless computation to do between synchronizations...

    /**
     * generates 32 bit pseudo-random numbers.
     * Adapted from http://www.snippets.org
     */
    public static int compute1(int x) {
        int lo = 16807 * (x & 0xFFFF);
        int hi = 16807 * (x >>> 16);
        lo += (hi & 0x7FFF) << 16;
        if ((lo & 0x80000000) != 0) {
            lo &= 0x7fffffff;
            ++lo;
        }
        lo += hi >>> 15;
        if (lo == 0 || (lo & 0x80000000) != 0) {
            lo &= 0x7fffffff;
            ++lo;
        }
        return lo;
    }

    /**
     *  Computes a linear congruential random number a random number
     *  of times.
     */
    public static int compute2(int x) {
        int loops = (x >>> 4) & 7;
        while (loops-- > 0) {
            x = (x * 2147483647) % 16807;
        }
        return x;
    }

    /**
     * Yet another random number generator
     */
    public static int compute3(int x) {
        int t = (x % 127773) * 16807 - (x / 127773) * 2836;
        return (t > 0) ? t : t + 0x7fffffff;
    }

    /**
     * Yet another random number generator
     */
    public static int compute4(int x) {
        return x * 134775813 + 1;
    }

    /**
     * Yet another random number generator
     */
    public static int compute5(int x) {
        return 36969 * (x & 65535) + (x >> 16);
    }

    /**
     * Marsaglia xorshift (1, 3, 10)
     */
    public static int compute6(int seed) {
        seed ^= seed << 1;
        seed ^= seed >>> 3;
        seed ^= (seed << 10);
        return seed;
    }

    /**
     * Marsaglia xorshift (6, 21, 7)
     */
    public static int compute7(int y) {
        y ^= y << 6;
        y ^= y >>> 21;
        y ^= (y << 7);
        return y;
    }

    // FNV: (x ^ 0x811c9dc5) * 0x01000193;  15485863;

    /**
     * Marsaglia xorshift for longs
     */
    public static long compute8(long x) {
        x ^= x << 13;
        x ^= x >>> 7;
        x ^= (x << 17);
        return x;
    }

    public static final class XorShift32Random {
        static final AtomicInteger seq = new AtomicInteger(8862213);
        int x = -1831433054;
        public XorShift32Random(int seed) { x = seed; }
        public XorShift32Random() {
            this((int) System.nanoTime() + seq.getAndAdd(129));
        }
        public int next() {
            x ^= x << 6;
            x ^= x >>> 21;
            x ^= (x << 7);
            return x;
        }
    }

    /** Multiplication-free RNG from Marsaglia "Xorshift RNGs" paper */
    public static final class MarsagliaRandom {
        static final AtomicInteger seq = new AtomicInteger(3122688);
        int x;
        int y = 842502087;
        int z = -715159705;
        int w = 273326509;
        public MarsagliaRandom(int seed) { x = seed; }
        public MarsagliaRandom() {
            this((int) System.nanoTime() + seq.getAndAdd(129));
        }
        public int next() {
            int t = x ^ (x << 11);
            x = y;
            y = z;
            z = w;
            return w = (w ^ (w >>> 19) ^ (t ^ (t >>> 8)));
        }
    }

    /**
     * Unsynchronized version of java.util.Random algorithm.
     */
    public static final class SimpleRandom {
        private static final long multiplier = 0x5DEECE66DL;
        private static final long addend = 0xBL;
        private static final long mask = (1L << 48) - 1;
        static final AtomicLong seq = new AtomicLong( -715159705);
        private long seed;

        SimpleRandom(long s) {
            seed = s;
        }

        SimpleRandom() {
            seed = System.nanoTime() + seq.getAndAdd(129);
        }

        public void setSeed(long s) {
            seed = s;
        }

        public int next() {
            long nextseed = (seed * multiplier + addend) & mask;
            seed = nextseed;
            return ((int) (nextseed >>> 17)) & 0x7FFFFFFF;
        }
    }

    public static class BarrierTimer implements Runnable {
        volatile boolean started;
        volatile long startTime;
        volatile long endTime;
        public void run() {
            long t = System.nanoTime();
            if (!started) {
                started = true;
                startTime = t;
            } else
                endTime = t;
        }
        public void clear() {
            started = false;
        }
        public long getTime() {
            return endTime - startTime;
        }
    }

    public static String rightJustify(long n) {
        // There's probably a better way to do this...
        String field = "         ";
        String num = Long.toString(n);
        if (num.length() >= field.length())
            return num;
        StringBuffer b = new StringBuffer(field);
        b.replace(b.length()-num.length(), b.length(), num);
        return b.toString();
    }

}
Revision:	1.14
Committed:	Thu Jan 15 18:34:19 2015 UTC (9 years, 4 months ago) by jsr166
Branch:	MAIN
CVS Tags:	HEAD
Changes since 1.13:	+0 -2 lines
Log Message:	delete extraneous blank lines
#	User	Rev	Content
1	dl	1.2	/*
2			* Written by Doug Lea with assistance from members of JCP JSR-166
3			* Expert Group and released to the public domain, as explained at
4	jsr166	1.11	* http://creativecommons.org/publicdomain/zero/1.0/
5	dl	1.2	*/
6	dl	1.1
7			import java.util.concurrent.*;
8			import java.util.concurrent.atomic.*;
9
10	jsr166	1.13	/**
11			* Misc utilities in JSR166 performance tests
12			*/
13	dl	1.1	class LoopHelpers {
14
15			static final SimpleRandom staticRNG = new SimpleRandom();
16
17			// Some mindless computation to do between synchronizations...
18
19			/**
20	jsr166	1.7	* generates 32 bit pseudo-random numbers.
21	dl	1.1	* Adapted from http://www.snippets.org
22			*/
23	jsr166	1.7	public static int compute1(int x) {
24	dl	1.1	int lo = 16807 * (x & 0xFFFF);
25			int hi = 16807 * (x >>> 16);
26			lo += (hi & 0x7FFF) << 16;
27			if ((lo & 0x80000000) != 0) {
28			lo &= 0x7fffffff;
29			++lo;
30			}
31			lo += hi >>> 15;
32			if (lo == 0 \|\| (lo & 0x80000000) != 0) {
33			lo &= 0x7fffffff;
34			++lo;
35			}
36			return lo;
37			}
38
39			/**
40			* Computes a linear congruential random number a random number
41			* of times.
42			*/
43	jsr166	1.7	public static int compute2(int x) {
44	dl	1.1	int loops = (x >>> 4) & 7;
45			while (loops-- > 0) {
46			x = (x * 2147483647) % 16807;
47			}
48			return x;
49			}
50
51			/**
52			* Yet another random number generator
53			*/
54	jsr166	1.7	public static int compute3(int x) {
55	dl	1.1	int t = (x % 127773) * 16807 - (x / 127773) * 2836;
56	jsr166	1.8	return (t > 0) ? t : t + 0x7fffffff;
57	dl	1.1	}
58
59			/**
60			* Yet another random number generator
61			*/
62	jsr166	1.7	public static int compute4(int x) {
63	dl	1.1	return x * 134775813 + 1;
64			}
65
66			/**
67			* Yet another random number generator
68			*/
69	jsr166	1.7	public static int compute5(int x) {
70	dl	1.1	return 36969 * (x & 65535) + (x >> 16);
71			}
72
73	dl	1.3	/**
74			* Marsaglia xorshift (1, 3, 10)
75			*/
76	jsr166	1.7	public static int compute6(int seed) {
77			seed ^= seed << 1;
78			seed ^= seed >>> 3;
79	dl	1.4	seed ^= (seed << 10);
80			return seed;
81	dl	1.3	}
82
83			/**
84			* Marsaglia xorshift (6, 21, 7)
85			*/
86			public static int compute7(int y) {
87	jsr166	1.7	y ^= y << 6;
88			y ^= y >>> 21;
89	dl	1.3	y ^= (y << 7);
90			return y;
91			}
92
93	dl	1.6	// FNV: (x ^ 0x811c9dc5) * 0x01000193; 15485863;
94	dl	1.3
95			/**
96			* Marsaglia xorshift for longs
97			*/
98	jsr166	1.7	public static long compute8(long x) {
99			x ^= x << 13;
100			x ^= x >>> 7;
101	dl	1.3	x ^= (x << 17);
102			return x;
103			}
104
105	dl	1.4	public static final class XorShift32Random {
106			static final AtomicInteger seq = new AtomicInteger(8862213);
107			int x = -1831433054;
108	jsr166	1.12	public XorShift32Random(int seed) { x = seed; }
109	jsr166	1.7	public XorShift32Random() {
110	jsr166	1.9	this((int) System.nanoTime() + seq.getAndAdd(129));
111	dl	1.4	}
112			public int next() {
113	jsr166	1.7	x ^= x << 6;
114			x ^= x >>> 21;
115	dl	1.4	x ^= (x << 7);
116			return x;
117			}
118			}
119
120	dl	1.3	/** Multiplication-free RNG from Marsaglia "Xorshift RNGs" paper */
121	dl	1.4	public static final class MarsagliaRandom {
122			static final AtomicInteger seq = new AtomicInteger(3122688);
123	dl	1.3	int x;
124			int y = 842502087;
125	dl	1.4	int z = -715159705;
126	dl	1.3	int w = 273326509;
127	dl	1.4	public MarsagliaRandom(int seed) { x = seed; }
128	jsr166	1.7	public MarsagliaRandom() {
129	jsr166	1.9	this((int) System.nanoTime() + seq.getAndAdd(129));
130	dl	1.4	}
131	dl	1.3	public int next() {
132			int t = x ^ (x << 11);
133	jsr166	1.7	x = y;
134			y = z;
135	dl	1.3	z = w;
136	dl	1.4	return w = (w ^ (w >>> 19) ^ (t ^ (t >>> 8)));
137	dl	1.3	}
138			}
139	dl	1.1
140			/**
141	dl	1.4	* Unsynchronized version of java.util.Random algorithm.
142	dl	1.1	*/
143	dl	1.4	public static final class SimpleRandom {
144	jsr166	1.10	private static final long multiplier = 0x5DEECE66DL;
145			private static final long addend = 0xBL;
146			private static final long mask = (1L << 48) - 1;
147	dl	1.4	static final AtomicLong seq = new AtomicLong( -715159705);
148			private long seed;
149
150			SimpleRandom(long s) {
151			seed = s;
152			}
153
154			SimpleRandom() {
155			seed = System.nanoTime() + seq.getAndAdd(129);
156			}
157	dl	1.1
158			public void setSeed(long s) {
159			seed = s;
160			}
161
162			public int next() {
163			long nextseed = (seed * multiplier + addend) & mask;
164			seed = nextseed;
165	jsr166	1.9	return ((int) (nextseed >>> 17)) & 0x7FFFFFFF;
166	dl	1.1	}
167			}
168
169			public static class BarrierTimer implements Runnable {
170	dl	1.5	volatile boolean started;
171			volatile long startTime;
172			volatile long endTime;
173	dl	1.1	public void run() {
174			long t = System.nanoTime();
175	dl	1.5	if (!started) {
176			started = true;
177	dl	1.1	startTime = t;
178	dl	1.5	} else
179	dl	1.1	endTime = t;
180			}
181			public void clear() {
182	dl	1.5	started = false;
183	dl	1.1	}
184			public long getTime() {
185			return endTime - startTime;
186			}
187			}
188
189			public static String rightJustify(long n) {
190			// There's probably a better way to do this...
191			String field = " ";
192			String num = Long.toString(n);
193			if (num.length() >= field.length())
194			return num;
195			StringBuffer b = new StringBuffer(field);
196			b.replace(b.length()-num.length(), b.length(), num);
197			return b.toString();
198			}
199	jsr166	1.7
200	dl	1.1	}