MurmurHash3のJava実装。32ビットと128ビットを求めるやつ。x86とx64で結果は異なる

EncodeUtils.java

public class EncodeUtils {
	
	public static int toIntBE(byte[] b, int i) {
		return ((b[i+0] << 24) + (b[i+1] << 16) + (b[i+2] << 8) + (b[i+3] << 0));
	}

	public static int toIntLE(byte[] b, int i) {
		return ((b[i+3] << 24) + (b[i+2] << 16) + (b[i+1] << 8) + (b[i+0] << 0));
	}
	
	public static long toLongBE(byte[] b, int offset) {
		
		return (((long)b[offset+0] << 56) +
				((long)(b[offset+1] & 255) << 48) +
				((long)(b[offset+2] & 255) << 40) +
				((long)(b[offset+3] & 255) << 32) +
				((long)(b[offset+4] & 255) << 24) +
				((b[offset+5] & 255) << 16) +
				((b[offset+6] & 255) <<  8) +
				((b[offset+7] & 255) <<  0));
		
	}

	public static long toLongLE(byte[] b, int offset) {
		
		return (((long)b[offset+7] << 56) +
				((long)(b[offset+6] & 255) << 48) +
				((long)(b[offset+5] & 255) << 40) +
				((long)(b[offset+4] & 255) << 32) +
				((long)(b[offset+3] & 255) << 24) +
				((b[offset+2] & 255) << 16) +
				((b[offset+1] & 255) <<  8) +
				((b[offset+0] & 255) <<  0));
		
	}
	
}

MurmurHash3.java

public class MurmurHash3 {
	
	private static int fmix(int h) {
		h ^= h >>> 16;
		h *= 0x85ebca6b;
		h ^= h >>> 13;
		h *= 0xc2b2ae35;
		h ^= h >>> 16;
		return h;
	}
	
	private static long fmix(long k) {
		k ^= k >>> 33;
		k *= 0xff51afd7ed558ccdL;
		k ^= k >>> 33;
		k *= 0xc4ceb9fe1a85ec53L;
		k ^= k >>> 33;
		return k;
	}
	
	public static int digest32_x86(byte[] data, int seed, boolean bigendian) {

		final int len = data.length;
		final int block_remain = len % 4;
		final int block_size = len - block_remain;

		int h1 = seed;
		int c1 = 0xcc9e2d51;
		int c2 = 0x1b873593;
		
		int i = 0;
		for (i = 0; i < block_size; i += 4) {
			int k1 = bigendian ? EncodeUtils.toIntBE(data, i) : EncodeUtils.toIntLE(data, i);
			
			k1 *= c1;
			k1 = Integer.rotateLeft(k1, 15);
			k1 *= c2;
			
			h1 ^= k1;
			h1 = Integer.rotateLeft(h1, 13);
			h1 = h1 * 5 + 0xe6546b64;
		}

		int k1 = 0;
		switch (block_remain) {
		case 3: k1 ^= data[i+2] << 16;
		case 2: k1 ^= data[i+1] << 8;
		case 1: k1 ^= data[i+0];
			k1 *= c1;
			k1 = Integer.rotateLeft(k1, 15);
			k1 *= c2;
			h1 ^=k1;
		}

		h1 ^= len;
		h1 = fmix(h1);
		
		return h1;
	}
	
	
	private static int updateK(int k, int cx1, int rnum, int cx2) {
		k *= cx1;
		k = Integer.rotateLeft(k, rnum);
		k *= cx2;
		return k;
	}
	
	private static int updateH(int h, int kx, int rnum, int hx, int cc) {
		h ^= kx;
		h = Integer.rotateLeft(h, rnum);
		h += hx;
		h = h * 5 + cc;
		return h;
	}

	private static long updateK(long k, long cx1, int rnum, long cx2) {
		k *= cx1;
		k = Long.rotateLeft(k, rnum);
		k *= cx2;
		return k;
	}
	
	private static long updateH(long h, long kx, int rnum, long hx, long cc) {
		h ^= kx;
		h = Long.rotateLeft(h, rnum);
		h += hx;
		h = h * 5 + cc;
		return h;
	}
	
	
	public static int[] digest128_x86(byte[] data, int seed, boolean bigendian) {
		
		final int c1 = 0x239b961b;
		final int c2 = 0xab0e9789;
		final int c3 = 0x38b34ae5;
		final int c4 = 0xa1e38b93;

		final int len = data.length;
		final int block_remain = len % 16;
		final int block_size = len - block_remain;

		int h1 = seed;
		int h2 = seed;
		int h3 = seed;
		int h4 = seed;
		
		int i = 0;
		for (i = 0; i < block_size; i += 16) {
			int k1 = bigendian ? EncodeUtils.toIntBE(data, i+0)  : EncodeUtils.toIntLE(data, i+0);
			int k2 = bigendian ? EncodeUtils.toIntBE(data, i+4)  : EncodeUtils.toIntLE(data, i+4);
			int k3 = bigendian ? EncodeUtils.toIntBE(data, i+8)  : EncodeUtils.toIntLE(data, i+8);
			int k4 = bigendian ? EncodeUtils.toIntBE(data, i+12) : EncodeUtils.toIntLE(data, i+12);
			
			k1 = updateK(k1, c1, 15, c2);
			h1 = updateH(h1, k1, 19, h2, 0x561ccd1b);
			
			k2 = updateK(k2, c2, 16, c3);
			h2 = updateH(h2, k2, 17, h3, 0x0bcaa747);
			
			k3 = updateK(k3, c3, 17, c4);
			h3 = updateH(h3, k3, 15, h4, 0x96cd1c35);
			
			k4 = updateK(k4, c4, 18, c1);
			h4 = updateH(h4, k4, 13, h1, 0x32ac3b17);
		}
		
		int k1 = 0;
		int k2 = 0;
		int k3 = 0;
		int k4 = 0;
		
		switch (block_remain) {
		case 15: k4 ^= data[i+14] << 16;
		case 14: k4 ^= data[i+13] << 8;
		case 13: k4 ^= data[i+12] << 0;
			k4 = updateK(k4, c4, 18, c1);
			h4 ^= k4;
		case 12: k3 ^= data[i+11] << 24;
		case 11: k3 ^= data[i+10] << 16;
		case 10: k3 ^= data[i+9] << 8;
		case 9: k3 ^= data[i+8] << 0;
			k3 = updateK(k3, c3, 17, c4);
			h3 ^= k3;
		case 8: k2 ^= data[i+7] << 24;
		case 7: k2 ^= data[i+6] << 16;
		case 6: k2 ^= data[i+5] << 8;
		case 5: k2 ^= data[i+4] << 0;
			k2 = updateK(k2, c2, 16, c3);
			h2 ^= k2;
		case 4: k1 ^= data[i+3] << 24;
		case 3: k1 ^= data[i+2] << 16;
		case 2: k1 ^= data[i+1] << 8;
		case 1: k1 ^= data[i+0] << 0;
			k1 = updateK(k1, c1, 15, c2);
			h1 ^= k1;
		}
		
		// finalization
		h1 ^= len;
		h2 ^= len;
		h3 ^= len;
		h4 ^= len;
		
		h1 += h2; h1 += h3; h1 += h4;
		h2 += h1; h3 += h1; h4 += h1;
		
		h1 = fmix(h1);
		h2 = fmix(h2);
		h3 = fmix(h3);
		h4 = fmix(h4);
		
		h1 += h2; h1 += h3; h1 += h4;
		h2 += h1; h3 += h1; h4 += h1;
		
		return new int[]{ h1, h2, h3, h4 };
		
	}
	
	public static long[] digest128_x64(byte[] data, int seed, boolean bigendian) {

		final long c1 = 0x87c37b91114253d5L;
		final long c2 = 0x4cf5ad432745937fL;

		final int len = data.length;
		final int block_remain = len % 16;
		final int block_size = len - block_remain;
		
		long h1 = seed;
		long h2 = seed;
		
		// body
		int i = 0;
		for (i = 0; i < block_size; i += 16) {
			long k1 = bigendian ? EncodeUtils.toLongBE(data, i + 0) : EncodeUtils.toLongLE(data, i + 0);
			long k2 = bigendian ? EncodeUtils.toLongBE(data, i + 8) : EncodeUtils.toLongLE(data, i + 8);
			
			k1 = updateK(k1, c1, 31, c2);
			h1 = updateH(h1, k1, 27, h2, 0x52dce729L);
			
			k2 = updateK(k2, c2, 33, c1);
			h2 = updateH(h2, k2, 31, h1, 0x38495ab5L);
		}
		
		// tail
		long k1 = 0;
		long k2 = 0;

		switch (block_remain) {
		case 15: k2 ^= (long)data[i+14] << 48;
		case 14: k2 ^= (long)data[i+13] << 40;
		case 13: k2 ^= (long)data[i+12] << 32;
		case 12: k2 ^= (long)data[i+11] << 24;
		case 11: k2 ^=       data[i+10] << 16;
		case 10: k2 ^=       data[i+9] << 8;
		case 9:  k2 ^=       data[i+8] << 0;
			k2 = updateK(k2, c2, 33, k2);
			h2 ^= k2;
		case 8: k1 ^= (long)data[i+7] << 56;
		case 7: k1 ^= (long)data[i+6] << 48;
		case 6: k1 ^= (long)data[i+5] << 40;
		case 5: k1 ^= (long)data[i+4] << 32;
		case 4: k1 ^= (long)data[i+3] << 24;
		case 3: k1 ^=       data[i+2] << 16;
		case 2: k1 ^=       data[i+1] << 8;
		case 1: k1 ^=       data[i+0] << 0;
			k1 = updateK(k1, c1, 31, c2);
			h1 ^= k1;
		}
		
		// finalization
		h1 ^= len;
		h2 ^= len;
		
		h1 += h2;
		h2 += h1;
		
		h1 = fmix(h1);
		h2 = fmix(h2);
		
		h1 += h2;
		h2 += h1;
		
		return new long[]{ h1, h2 };
		
	}
	
}