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diff --git a/src/main/java/org/linaro/benchmarks/algorithm/BitopsNSieve.java b/src/main/java/org/linaro/benchmarks/algorithm/BitopsNSieve.java
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+++ b/src/main/java/org/linaro/benchmarks/algorithm/BitopsNSieve.java
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+/*
+ * Copyright (C) 2015 Linaro Limited. Ported to Java from:
+ *  https://github.com/WebKit/webkit/blob/master/PerformanceTests/SunSpider/tests/sunspider-1.0.2/bitops-nsieve-bits.js
+ *
+ * Description:     Bitops prime number sieve, used for finding prime numbers.
+ * Main Focus:      Bitwise operations.
+ *
+ */
+
+// The Great Computer Language Shootout
+//  http://shootout.alioth.debian.org/
+//
+//  Contributed by Ian Osgood
+
+// http://benchmarksgame.alioth.debian.org/license.html  (BSD 3-clause license)
+// See NOTICE file for the license
+
+package org.linaro.benchmarks.algorithm;
+
+import java.lang.Integer;
+import java.lang.System;
+import org.openjdk.jmh.annotations.*;
+import java.util.concurrent.TimeUnit;
+
+@BenchmarkMode(Mode.AverageTime)
+@OutputTimeUnit(TimeUnit.MICROSECONDS)
+@State(Scope.Benchmark)
+
+public class BitopsNSieve {
+  private static final int BITOPS_NSIEVE_EXPECTED = -1431657430;
+
+  // As per the original, this function is not used.
+  private String pad(int n, int width) {
+    String s = Integer.toString(n);
+    while (s.length() < width) {
+      s = ' ' + s;
+    }
+    return s;
+  }
+
+  private void primes(int[] isPrime, int n) {
+    // As per the original, this variable can be optimised out.
+    int count = 0;
+    final int m = 10000 << n;
+    final int size = m + 31 >> 5;
+
+    for (int i = 0; i < size; i++) {
+      isPrime[i] = 0xffffffff;
+    }
+
+    for (int i = 2; i < m; i++) {
+      if ((isPrime[i >> 5] & 1 << (i & 31)) != 0) {
+        for (int j = i + 1; j < m; j += i) {
+          isPrime[j >> 5] &= ~ (1 << (j & 31));
+        }
+        count++;
+      }
+    }
+  }
+
+  private int[] sieve() {
+    int[] isPrime = null;
+    // As per the original, this loop will have just one iteration.
+    for (int i = 4; i <= 4; i++) {
+      isPrime = new int[(10000 << i) + 31 >> 5];
+      primes(isPrime, i);
+    }
+    return isPrime;
+  }
+
+  @Benchmark
+  public void jmhTimeBitopsNSieve() {
+    sieve();
+  }
+}