X-Git-Url: http://git.cascardo.eti.br/?a=blobdiff_plain;f=lib%2Fhash.c;h=aa898a3b8f864b194128e60c8cc1797077f83707;hb=d0a46cb4608e632f5028034762f0adde2ce947a0;hp=f1daa6ba782389a956cd5ae508927546d637f3b0;hpb=34e63086edddcae06d7c1a4fa84fec0861e50758;p=cascardo%2Fovs.git

diff --git a/lib/hash.c b/lib/hash.c
index f1daa6ba7..aa898a3b8 100644
--- a/lib/hash.c
+++ b/lib/hash.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008, 2009 Nicira Networks.
+ * Copyright (c) 2008, 2009, 2010, 2012, 2013, 2014 Nicira, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,70 +16,322 @@
 #include <config.h>
 #include "hash.h"
 #include <string.h>
+#include "unaligned.h"
 
-/* Returns the hash of the 'n' 32-bit words at 'p', starting from 'basis'.
- * 'p' must be properly aligned. */
+/* Returns the hash of 'a', 'b', and 'c'. */
 uint32_t
-hash_words(const uint32_t *p, size_t n, uint32_t basis)
+hash_3words(uint32_t a, uint32_t b, uint32_t c)
 {
-    uint32_t a, b, c;
+    return hash_finish(hash_add(hash_add(hash_add(a, 0), b), c), 12);
+}
 
-    a = b = c = 0xdeadbeef + (((uint32_t) n) << 2) + basis;
+/* Returns the hash of the 'n' bytes at 'p', starting from 'basis'. */
+uint32_t
+hash_bytes(const void *p_, size_t n, uint32_t basis)
+{
+    const uint32_t *p = p_;
+    size_t orig_n = n;
+    uint32_t hash;
 
-    while (n > 3) {
-        a += p[0];
-        b += p[1];
-        c += p[2];
-        HASH_MIX(a, b, c);
-        n -= 3;
-        p += 3;
+    hash = basis;
+    while (n >= 4) {
+        hash = hash_add(hash, get_unaligned_u32(p));
+        n -= 4;
+        p += 1;
     }
 
-    switch (n) {
-    case 3:
-        c += p[2];
-        /* fall through */
-    case 2:
-        b += p[1];
-        /* fall through */
-    case 1:
-        a += p[0];
-        HASH_FINAL(a, b, c);
-        /* fall through */
-    case 0:
-        break;
+    if (n) {
+        uint32_t tmp = 0;
+
+        memcpy(&tmp, p, n);
+        hash = hash_add(hash, tmp);
     }
-    return c;
+
+    return hash_finish(hash, orig_n);
 }
 
-/* Returns the hash of the 'n' bytes at 'p', starting from 'basis'. */
 uint32_t
-hash_bytes(const void *p_, size_t n, uint32_t basis)
+hash_double(double x, uint32_t basis)
+{
+    uint32_t value[2];
+    BUILD_ASSERT_DECL(sizeof x == sizeof value);
+
+    memcpy(value, &x, sizeof value);
+    return hash_3words(value[0], value[1], basis);
+}
+
+uint32_t
+hash_words__(const uint32_t p[], size_t n_words, uint32_t basis)
+{
+    return hash_words_inline(p, n_words, basis);
+}
+
+uint32_t
+hash_words64__(const uint64_t p[], size_t n_words, uint32_t basis)
 {
-    const uint8_t *p = p_;
-    uint32_t a, b, c;
-    uint32_t tmp[3];
-
-    a = b = c = 0xdeadbeef + n + basis;
-
-    while (n >= sizeof tmp) {
-        memcpy(tmp, p, sizeof tmp);
-        a += tmp[0];
-        b += tmp[1];
-        c += tmp[2];
-        HASH_MIX(a, b, c);
-        n -= sizeof tmp;
-        p += sizeof tmp;
+    return hash_words64_inline(p, n_words, basis);
+}
+
+#if !(defined(__x86_64__))
+void
+hash_bytes128(const void *p_, size_t len, uint32_t basis, ovs_u128 *out)
+{
+    const uint32_t c1 = 0x239b961b;
+    const uint32_t c2 = 0xab0e9789;
+    const uint32_t c3 = 0x38b34ae5;
+    const uint32_t c4 = 0xa1e38b93;
+    const uint8_t *tail, *data = (const uint8_t *)p_;
+    const uint32_t *blocks = (const uint32_t *)p_;
+    const int nblocks = len / 16;
+    uint32_t h1 = basis;
+    uint32_t h2 = basis;
+    uint32_t h3 = basis;
+    uint32_t h4 = basis;
+    uint32_t k1, k2, k3, k4;
+
+    /* Body */
+    for (int i = 0; i < nblocks; i++) {
+        uint32_t k1 = get_unaligned_u32(&blocks[i * 4 + 0]);
+        uint32_t k2 = get_unaligned_u32(&blocks[i * 4 + 1]);
+        uint32_t k3 = get_unaligned_u32(&blocks[i * 4 + 2]);
+        uint32_t k4 = get_unaligned_u32(&blocks[i * 4 + 3]);
+
+        k1 *= c1;
+        k1 = hash_rot(k1, 15);
+        k1 *= c2;
+        h1 ^= k1;
+
+        h1 = hash_rot(h1, 19);
+        h1 += h2;
+        h1 = h1 * 5 + 0x561ccd1b;
+
+        k2 *= c2;
+        k2 = hash_rot(k2, 16);
+        k2 *= c3;
+        h2 ^= k2;
+
+        h2 = hash_rot(h2, 17);
+        h2 += h3;
+        h2 = h2 * 5 + 0x0bcaa747;
+
+        k3 *= c3;
+        k3 = hash_rot(k3, 17);
+        k3 *= c4;
+        h3 ^= k3;
+
+        h3 = hash_rot(h3, 15);
+        h3 += h4;
+        h3 = h3 * 5 + 0x96cd1c35;
+
+        k4 *= c4;
+        k4 = hash_rot(k4, 18);
+        k4 *= c1;
+        h4 ^= k4;
+
+        h4 = hash_rot(h4, 13);
+        h4 += h1;
+        h4 = h4 * 5 + 0x32ac3b17;
     }
 
-    if (n) {
-        tmp[0] = tmp[1] = tmp[2] = 0;
-        memcpy(tmp, p, n);
-        a += tmp[0];
-        b += tmp[1];
-        c += tmp[2];
-        HASH_FINAL(a, b, c);
+    /* Tail */
+    k1 = k2 = k3 = k4 = 0;
+    tail = data + nblocks * 16;
+    switch (len & 15) {
+    case 15:
+        k4 ^= tail[14] << 16;
+    case 14:
+        k4 ^= tail[13] << 8;
+    case 13:
+        k4 ^= tail[12] << 0;
+        k4 *= c4;
+        k4 = hash_rot(k4, 18);
+        k4 *= c1;
+        h4 ^= k4;
+
+    case 12:
+        k3 ^= tail[11] << 24;
+    case 11:
+        k3 ^= tail[10] << 16;
+    case 10:
+        k3 ^= tail[9] << 8;
+    case 9:
+        k3 ^= tail[8] << 0;
+        k3 *= c3;
+        k3 = hash_rot(k3, 17);
+        k3 *= c4;
+        h3 ^= k3;
+
+    case 8:
+        k2 ^= tail[7] << 24;
+    case 7:
+        k2 ^= tail[6] << 16;
+    case 6:
+        k2 ^= tail[5] << 8;
+    case 5:
+        k2 ^= tail[4] << 0;
+        k2 *= c2;
+        k2 = hash_rot(k2, 16);
+        k2 *= c3;
+        h2 ^= k2;
+
+    case 4:
+        k1 ^= tail[3] << 24;
+    case 3:
+        k1 ^= tail[2] << 16;
+    case 2:
+        k1 ^= tail[1] << 8;
+    case 1:
+        k1 ^= tail[0] << 0;
+        k1 *= c1;
+        k1 = hash_rot(k1, 15);
+        k1 *= 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 = mhash_finish(h1);
+    h2 = mhash_finish(h2);
+    h3 = mhash_finish(h3);
+    h4 = mhash_finish(h4);
+
+    h1 += h2;
+    h1 += h3;
+    h1 += h4;
+    h2 += h1;
+    h3 += h1;
+    h4 += h1;
+
+    out->u32[0] = h1;
+    out->u32[1] = h2;
+    out->u32[2] = h3;
+    out->u32[3] = h4;
+}
+
+#else /* __x86_64__ */
+
+static inline uint64_t
+hash_rot64(uint64_t x, int8_t r)
+{
+    return (x << r) | (x >> (64 - r));
+}
+
+static inline uint64_t
+fmix64(uint64_t k)
+{
+    k ^= k >> 33;
+    k *= 0xff51afd7ed558ccdULL;
+    k ^= k >> 33;
+    k *= 0xc4ceb9fe1a85ec53ULL;
+    k ^= k >> 33;
+
+    return k;
+}
+
+void
+hash_bytes128(const void *p_, size_t len, uint32_t basis, ovs_u128 *out)
+{
+    const uint64_t c1 = 0x87c37b91114253d5ULL;
+    const uint64_t c2 = 0x4cf5ad432745937fULL;
+    const uint8_t *tail, *data = (const uint8_t *)p_;
+    const uint64_t *blocks = (const uint64_t *)p_;
+    const int nblocks = len / 16;
+    uint64_t h1 = basis;
+    uint64_t h2 = basis;
+    uint64_t k1, k2;
+
+    /* Body */
+    for (int i = 0; i < nblocks; i++) {
+        k1 = get_unaligned_u64(&blocks[i * 2 + 0]);
+        k2 = get_unaligned_u64(&blocks[i * 2 + 1]);
+
+        k1 *= c1;
+        k1 = hash_rot64(k1, 31);
+        k1 *= c2;
+        h1 ^= k1;
+
+        h1 = hash_rot64(h1, 27);
+        h1 += h2;
+        h1 = h1 * 5 + 0x52dce729;
+
+        k2 *= c2;
+        k2 = hash_rot64(k2, 33);
+        k2 *= c1;
+        h2 ^= k2;
+
+        h2 = hash_rot64(h2, 31);
+        h2 += h1;
+        h2 = h2 * 5 + 0x38495ab5;
     }
 
-    return c;
+    /* Tail */
+    k1 = 0;
+    k2 = 0;
+    tail = data + nblocks * 16;
+    switch (len & 15) {
+    case 15:
+        k2 ^= ((uint64_t) tail[14]) << 48;
+    case 14:
+        k2 ^= ((uint64_t) tail[13]) << 40;
+    case 13:
+        k2 ^= ((uint64_t) tail[12]) << 32;
+    case 12:
+        k2 ^= ((uint64_t) tail[11]) << 24;
+    case 11:
+        k2 ^= ((uint64_t) tail[10]) << 16;
+    case 10:
+        k2 ^= ((uint64_t) tail[9]) << 8;
+    case 9:
+        k2 ^= ((uint64_t) tail[8]) << 0;
+        k2 *= c2;
+        k2 = hash_rot64(k2, 33);
+        k2 *= c1;
+        h2 ^= k2;
+
+    case 8:
+        k1 ^= ((uint64_t) tail[7]) << 56;
+    case 7:
+        k1 ^= ((uint64_t) tail[6]) << 48;
+    case 6:
+        k1 ^= ((uint64_t) tail[5]) << 40;
+    case 5:
+        k1 ^= ((uint64_t) tail[4]) << 32;
+    case 4:
+        k1 ^= ((uint64_t) tail[3]) << 24;
+    case 3:
+        k1 ^= ((uint64_t) tail[2]) << 16;
+    case 2:
+        k1 ^= ((uint64_t) tail[1]) << 8;
+    case 1:
+        k1 ^= ((uint64_t) tail[0]) << 0;
+        k1 *= c1;
+        k1 = hash_rot64(k1, 31);
+        k1 *= c2;
+        h1 ^= k1;
+    };
+
+    /* Finalization */
+    h1 ^= len;
+    h2 ^= len;
+    h1 += h2;
+    h2 += h1;
+    h1 = fmix64(h1);
+    h2 = fmix64(h2);
+    h1 += h2;
+    h2 += h1;
+
+    out->u64.lo = h1;
+    out->u64.hi = h2;
 }
+#endif /* __x86_64__ */