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/* |
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* Written by Doug Lea with assistance from members of JCP JSR-166 |
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* Expert Group and released to the public domain, as explained at |
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* http://creativecommons.org/publicdomain/zero/1.0/ |
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*/ |
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|
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public class FinalLongTest { |
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static int npairs = 2; |
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static int iters = 10000000; |
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static int LEN = 2; |
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static final Long[] nums = new Long[LEN]; |
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static volatile boolean done; |
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static volatile long total; |
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static Long n0 = new Long(21); |
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static Long n1 = new Long(22); |
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static Long n2 = new Long(23); |
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static Long n3 = new Long(23); |
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|
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public static void main(String[] args) { |
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for (int i = 0; i < LEN; ++i) |
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nums[i] = new Long(i+1); |
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Thread[] ps = new Thread[npairs]; |
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Thread[] as = new Reader[npairs]; |
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for (int i = 0; i < npairs; ++i) { |
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ps[i] = new Writer(); |
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as[i] = new Reader(); |
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} |
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for (int i = 0; i < as.length; ++i) { |
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ps[i].start(); |
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as[i].start(); |
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} |
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} |
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|
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static long nextRandom(long seed) { |
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return (seed * 0x5DEECE66DL + 0xBL) & ((1L << 48) - 1); |
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} |
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|
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static long initialSeed(Object x) { |
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return (System.currentTimeMillis() + x.hashCode()) | 1; |
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} |
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|
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static class Writer extends Thread { |
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public void run() { |
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long s = initialSeed(this); |
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int n = iters / 2; |
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Long[] ns = nums; |
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|
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while (n-- > 0) { |
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// int k = (int) (s & (LEN-1)); |
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// if (k < 0 || k >= LEN) k = 1; |
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// int l = (k+1) & (LEN-1); |
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// if (l < 0 || l >= LEN) l = 0; |
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// int k = (s & 1) == 0 ? 0 : 1; |
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// int l = (k == 0) ? 1 : 0; |
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if ((s & (LEN-1)) == 0) { |
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n3 = n1; |
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n0 = new Long(s); |
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n2 = n1; |
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n1 = new Long(s); |
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} |
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else { |
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n3 = n0; |
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n1 = new Long(s); |
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n2 = n0; |
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n0 = new Long(s); |
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} |
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s = nextRandom(s); |
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if (s == 0) s = initialSeed(this); |
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} |
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done = true; |
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total += s; |
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} |
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} |
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|
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static class Reader extends Thread { |
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public void run() { |
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int n = iters; |
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long s = initialSeed(this); |
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while (s != 0 && n > 0) { |
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long nexts; // = nums[(int) (s & (LEN-1))].longValue(); |
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if ((s & (LEN-1)) == 0) |
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nexts = n0.longValue(); |
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else |
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nexts = n1.longValue(); |
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if (nexts != 0) { |
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if ((s & 4) == 0) |
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nexts = n2.longValue(); |
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else |
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nexts = n3.longValue(); |
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} |
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|
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if (nexts != s) |
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--n; |
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else if (done) |
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break; |
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s = nexts; |
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} |
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done = true; |
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total += s; |
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if (s == 0) |
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throw new Error("Saw uninitialized value"); |
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} |
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} |
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} |