From da76459dc21b5af2449af2d36eb95226cb186ce2 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 28 Apr 2024 11:35:11 +0200 Subject: Adding upstream version 2.6.12. Signed-off-by: Daniel Baumann --- tests/exp/test_hashes.c | 559 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 559 insertions(+) create mode 100644 tests/exp/test_hashes.c (limited to 'tests/exp/test_hashes.c') diff --git a/tests/exp/test_hashes.c b/tests/exp/test_hashes.c new file mode 100644 index 0000000..39cb965 --- /dev/null +++ b/tests/exp/test_hashes.c @@ -0,0 +1,559 @@ +/* + This file only show how many operations a hash is able to handle. + It don't show the distribution nor collisions. + + gcc -Wall -O3 -o test_hashes test_hashes.c + ./test_hashes |sort -k 3 -r + */ +#include +#include +#include +#include +#include +#include +//#include + + +static struct timeval timeval_current(void) +{ + struct timeval tv; + gettimeofday(&tv, NULL); + return tv; +} + +static double timeval_elapsed(struct timeval *tv) +{ + struct timeval tv2 = timeval_current(); + return (tv2.tv_sec - tv->tv_sec) + + (tv2.tv_usec - tv->tv_usec)*1.0e-6; +} + +#define HAPROXY_BACKENDS 4 + +unsigned long haproxy_uri_hash(char *uri, int uri_len){ + + unsigned long hash = 0; + int c; + + while (uri_len--) { + c = *uri++; + if (c == '?') + break; + hash = c + (hash << 6) + (hash << 16) - hash; + } + + return hash%HAPROXY_BACKENDS; /* I assume 4 active backends */ +} /* end haproxy_hash() */ + +/* + * http://eternallyconfuzzled.com/tuts/algorithms/jsw_tut_hashing.aspx + */ +unsigned sax_hash ( void *key, int len ) +{ + unsigned char *p = key; + unsigned h = 0; + int i; + + for ( i = 0; i < len; i++ ) + h ^= ( h << 5 ) + ( h >> 2 ) + p[i]; + + return h; +} + +#include +/* len 4 for ipv4 and 16 for ipv6 */ +unsigned int haproxy_server_hash(const char *addr, int len){ + unsigned int h, l; + l = h = 0; + + while ((l + sizeof (int)) <= len) { + h ^= ntohl(*(unsigned int *)(&addr[l])); + l += sizeof (int); + } + return h %= HAPROXY_BACKENDS; +}/* end haproxy_server_hash() */ + + +int hashpjw(const void *key) { + + const char *ptr; + unsigned int val; + /********************************************************************* + * * + * Hash the key by performing a number of bit operations on it. * + * * + *********************************************************************/ + + val = 0; + ptr = key; + + while (*ptr != '\0') { + + int tmp; + + val = (val << 4) + (*ptr); + + if((tmp = (val & 0xf0000000))) { + val = val ^ (tmp >> 24); + val = val ^ tmp; + } + ptr++; + }/* end while */ + + return val; +}/* end hashpjw */ + +static unsigned long +hash_djbx33( + register unsigned char *key, + register size_t len) +{ + register unsigned long hash = 5381; + + /* the hash unrolled eight times */ + for (; len >= 8; len -= 8) { + hash = ((hash << 5) + hash) + *key++; + hash = ((hash << 5) + hash) + *key++; + hash = ((hash << 5) + hash) + *key++; + hash = ((hash << 5) + hash) + *key++; + hash = ((hash << 5) + hash) + *key++; + hash = ((hash << 5) + hash) + *key++; + hash = ((hash << 5) + hash) + *key++; + hash = ((hash << 5) + hash) + *key++; + } + switch (len) { + case 7: hash = ((hash << 5) + hash) + *key++; /* fallthrough... */ + case 6: hash = ((hash << 5) + hash) + *key++; /* fallthrough... */ + case 5: hash = ((hash << 5) + hash) + *key++; /* fallthrough... */ + case 4: hash = ((hash << 5) + hash) + *key++; /* fallthrough... */ + case 3: hash = ((hash << 5) + hash) + *key++; /* fallthrough... */ + case 2: hash = ((hash << 5) + hash) + *key++; /* fallthrough... */ + case 1: hash = ((hash << 5) + hash) + *key++; break; + default: /* case 0: */ break; + } + return hash; +} + +typedef unsigned long int ub4; /* unsigned 4-byte quantities */ +typedef unsigned char ub1; /* unsigned 1-byte quantities */ + +ub4 bernstein(ub1 *key, ub4 len, ub4 level){ + ub4 hash = level; + ub4 i; + for (i=0; i>= 2; + + /* Main loop */ + for (;len > 0; len--) { + hash += get16bits (data); + tmp = (get16bits (data+2) << 11) ^ hash; + hash = (hash << 16) ^ tmp; + data += 2*sizeof (uint16_t); + hash += hash >> 11; + } + + /* Handle end cases */ + switch (rem) { + case 3: hash += get16bits (data); + hash ^= hash << 16; + hash ^= data[sizeof (uint16_t)] << 18; + hash += hash >> 11; + break; + case 2: hash += get16bits (data); + hash ^= hash << 11; + hash += hash >> 17; + break; + case 1: hash += *data; + hash ^= hash << 10; + hash += hash >> 1; + } + + /* Force "avalanching" of final 127 bits */ + hash ^= hash << 3; + hash += hash >> 5; + hash ^= hash << 4; + hash += hash >> 17; + hash ^= hash << 25; + hash += hash >> 6; + + return hash; +} + +/* + * This variant is about 15% faster. + */ +uint32_t SuperFastHash2 (const char * data, int len) { +uint32_t hash = len, tmp; +int rem; + + if (len <= 0 || data == NULL) return 0; + + rem = len & 3; + len >>= 2; + + /* Main loop */ + for (;len > 0; len--) { + register uint32_t next; + next = get16bits(data+2); + hash += get16bits(data); + tmp = (next << 11) ^ hash; + hash = (hash << 16) ^ tmp; + data += 2*sizeof (uint16_t); + hash += hash >> 11; + } + + /* Handle end cases */ + switch (rem) { + case 3: hash += get16bits (data); + hash ^= hash << 16; + hash ^= data[sizeof (uint16_t)] << 18; + hash += hash >> 11; + break; + case 2: hash += get16bits (data); + hash ^= hash << 11; + hash += hash >> 17; + break; + case 1: hash += *data; + hash ^= hash << 10; + hash += hash >> 1; + } + + /* Force "avalanching" of final 127 bits */ + hash ^= hash << 3; + hash += hash >> 5; + hash ^= hash << 4; + hash += hash >> 17; + hash ^= hash << 25; + hash += hash >> 6; + + return hash; +} + +/* + * 32 bit FNV-0 hash type + */ +typedef unsigned long Fnv32_t; + +/* + * fnv_32a_str - perform a 32 bit Fowler/Noll/Vo FNV-1a hash on a string + * + * input: + * str - string to hash + * hval - previous hash value or 0 if first call + * + * returns: + * 32 bit hash as a static hash type + * + * NOTE: To use the recommended 32 bit FNV-1a hash, use FNV1_32A_INIT as the + * hval arg on the first call to either fnv_32a_buf() or fnv_32a_str(). + */ +Fnv32_t +fnv_32a_str(char *str, Fnv32_t hval) +{ + unsigned char *s = (unsigned char *)str; /* unsigned string */ + + /* + * FNV-1a hash each octet in the buffer + */ + while (*s) { + + /* xor the bottom with the current octet */ + hval ^= (Fnv32_t)*s++; + +/* #define NO_FNV_GCC_OPTIMIZATION */ + /* multiply by the 32 bit FNV magic prime mod 2^32 */ +#if defined(NO_FNV_GCC_OPTIMIZATION) + /* + * 32 bit magic FNV-1a prime + */ +#define FNV_32_PRIME ((Fnv32_t)0x01000193) + hval *= FNV_32_PRIME; +#else + hval += (hval<<1) + (hval<<4) + (hval<<7) + (hval<<8) + (hval<<24); +#endif + } + + /* return our new hash value */ + return hval; +} + +/* + * from lookup3.c, by Bob Jenkins, May 2006, Public Domain. + */ + +#define rot(x,k) (((x)<<(k)) | ((x)>>(32-(k)))) + +/* +------------------------------------------------------------------------------- +mix -- mix 3 32-bit values reversibly. + +This is reversible, so any information in (a,b,c) before mix() is +still in (a,b,c) after mix(). + +If four pairs of (a,b,c) inputs are run through mix(), or through +mix() in reverse, there are at least 32 bits of the output that +are sometimes the same for one pair and different for another pair. +This was tested for: +* pairs that differed by one bit, by two bits, in any combination + of top bits of (a,b,c), or in any combination of bottom bits of + (a,b,c). +* "differ" is defined as +, -, ^, or ~^. For + and -, I transformed + the output delta to a Gray code (a^(a>>1)) so a string of 1's (as + is commonly produced by subtraction) look like a single 1-bit + difference. +* the base values were pseudorandom, all zero but one bit set, or + all zero plus a counter that starts at zero. + +Some k values for my "a-=c; a^=rot(c,k); c+=b;" arrangement that +satisfy this are + 4 6 8 16 19 4 + 9 15 3 18 27 15 + 14 9 3 7 17 3 +Well, "9 15 3 18 27 15" didn't quite get 32 bits diffing +for "differ" defined as + with a one-bit base and a two-bit delta. I +used http://burtleburtle.net/bob/hash/avalanche.html to choose +the operations, constants, and arrangements of the variables. + +This does not achieve avalanche. There are input bits of (a,b,c) +that fail to affect some output bits of (a,b,c), especially of a. The +most thoroughly mixed value is c, but it doesn't really even achieve +avalanche in c. + +This allows some parallelism. Read-after-writes are good at doubling +the number of bits affected, so the goal of mixing pulls in the opposite +direction as the goal of parallelism. I did what I could. Rotates +seem to cost as much as shifts on every machine I could lay my hands +on, and rotates are much kinder to the top and bottom bits, so I used +rotates. +------------------------------------------------------------------------------- +*/ +#define mix(a,b,c) \ +{ \ + a -= c; a ^= rot(c, 4); c += b; \ + b -= a; b ^= rot(a, 6); a += c; \ + c -= b; c ^= rot(b, 8); b += a; \ + a -= c; a ^= rot(c,16); c += b; \ + b -= a; b ^= rot(a,19); a += c; \ + c -= b; c ^= rot(b, 4); b += a; \ +} + +/* +------------------------------------------------------------------------------- +final -- final mixing of 3 32-bit values (a,b,c) into c + +Pairs of (a,b,c) values differing in only a few bits will usually +produce values of c that look totally different. This was tested for +* pairs that differed by one bit, by two bits, in any combination + of top bits of (a,b,c), or in any combination of bottom bits of + (a,b,c). +* "differ" is defined as +, -, ^, or ~^. For + and -, I transformed + the output delta to a Gray code (a^(a>>1)) so a string of 1's (as + is commonly produced by subtraction) look like a single 1-bit + difference. +* the base values were pseudorandom, all zero but one bit set, or + all zero plus a counter that starts at zero. + +These constants passed: + 14 11 25 16 4 14 24 + 12 14 25 16 4 14 24 +and these came close: + 4 8 15 26 3 22 24 + 10 8 15 26 3 22 24 + 11 8 15 26 3 22 24 +------------------------------------------------------------------------------- +*/ +#define final(a,b,c) \ +{ \ + c ^= b; c -= rot(b,14); \ + a ^= c; a -= rot(c,11); \ + b ^= a; b -= rot(a,25); \ + c ^= b; c -= rot(b,16); \ + a ^= c; a -= rot(c,4); \ + b ^= a; b -= rot(a,14); \ + c ^= b; c -= rot(b,24); \ +} + +/* +-------------------------------------------------------------------- + This works on all machines. To be useful, it requires + -- that the key be an array of uint32_t's, and + -- that the length be the number of uint32_t's in the key + + The function hashword() is identical to hashlittle() on little-endian + machines, and identical to hashbig() on big-endian machines, + except that the length has to be measured in uint32_ts rather than in + bytes. hashlittle() is more complicated than hashword() only because + hashlittle() has to dance around fitting the key bytes into registers. +-------------------------------------------------------------------- +*/ +uint32_t hashword( +const uint32_t *k, /* the key, an array of uint32_t values */ +size_t length, /* the length of the key, in uint32_ts */ +uint32_t initval) /* the previous hash, or an arbitrary value */ +{ + uint32_t a,b,c; + + /* Set up the internal state */ + a = b = c = 0xdeadbeef + (((uint32_t)length)<<2) + initval; + + /*------------------------------------------------- handle most of the key */ + while (length > 3) + { + a += k[0]; + b += k[1]; + c += k[2]; + mix(a,b,c); + length -= 3; + k += 3; + } + + /*------------------------------------------- handle the last 3 uint32_t's */ + switch(length) /* all the case statements fall through */ + { + case 3 : c+=k[2]; + case 2 : b+=k[1]; + case 1 : a+=k[0]; + final(a,b,c); + case 0: /* case 0: nothing left to add */ + break; + } + /*------------------------------------------------------ report the result */ + return c; +} + +/* from K&R book site 139 */ +#define HASHSIZE 101 + +unsigned kr_hash(char *s){ + unsigned hashval; + + for(hashval = 0; *s != '\0';s++) + hashval = *s + 31 * hashval; + + return hashval % HASHSIZE; + +} /* end kr_hash() */ + +unsigned fnv_hash ( void *key, int len ) +{ + unsigned char *p = key; + unsigned h = 2166136261; + int i; + + for ( i = 0; i < len; i++ ) + h = ( h * 16777619 ) ^ p[i]; + + return h; +} + +unsigned oat_hash ( void *key, int len ) +{ + unsigned char *p = key; + unsigned h = 0; + int i; + + for ( i = 0; i < len; i++ ) { + h += p[i]; + h += ( h << 10 ); + h ^= ( h >> 6 ); + } + + h += ( h << 3 ); + h ^= ( h >> 11 ); + h += ( h << 15 ); + + return h; +} + +unsigned wt_hash ( void *key, int len ) +{ + unsigned char *p = key; + unsigned h = 0x783c965aUL; + unsigned step = 16; + + for (; len > 0; len--) { + h ^= *p * 9; + p++; + h = (h << step) | (h >> (32-step)); + step ^= h; + step &= 0x1F; + } + + return h; +} + + +#define run_test(fct, args) { \ + unsigned long loop, count; \ + volatile unsigned long result; \ + double delta; \ + struct timeval tv; \ + fprintf(stderr, "Starting %s\n", #fct); \ + tv = timeval_current(); \ + count = 0; \ + do { \ + delta = timeval_elapsed(&tv); \ + for (loop = 0; loop < 1000; loop++) { \ + result = fct args; \ + count++; \ + } \ + } while (delta < 1.0); \ + fprintf(stdout, "%-20s : %10.0f run/sec\n", #fct, count/delta); \ + fflush(stdout); \ +} + +int main(){ + + char **start; + int len; + + char *urls[] = { + "http://www.microsoft.com/shared/core/1/webservice/navigation.asmx/DisplayDownlevelNavHtml", + NULL + }; + + start = urls; + len = strlen(*urls); + + run_test(wt_hash, (*urls, len)); + run_test(SuperFastHash2, (*urls, len)); + run_test(SuperFastHash, (*urls, len)); + run_test(haproxy_uri_hash, (*urls, len)); + run_test(haproxy_server_hash, (*urls, len)); + run_test(hashpjw, (*urls)); + run_test(hash_djbx33, ((unsigned char *)*urls, len)); + run_test(bernstein, ((unsigned char *)*urls, len, 4)); + run_test(fnv_32a_str, (*urls, 0)); + run_test(hashword, ((const uint32_t *)*urls,strlen(*urls),0)); + run_test(kr_hash, (*urls)); + run_test(sax_hash, (*urls, len)); + run_test(fnv_hash, (*urls, len)); + run_test(oat_hash, (*urls, len)); + + return 0; + +}/* end main() */ -- cgit v1.2.3