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Edit File: zaphod32_hash.h
#ifndef DEBUG_ZAPHOD32_HASH #define DEBUG_ZAPHOD32_HASH 0 #if DEBUG_ZAPHOD32_HASH == 1 #include <stdio.h> #define ZAPHOD32_WARN6(pat,v0,v1,v2,v3,v4,v5) printf(pat, v0, v1, v2, v3, v4, v5) #define ZAPHOD32_WARN5(pat,v0,v1,v2,v3,v4) printf(pat, v0, v1, v2, v3, v4) #define ZAPHOD32_WARN4(pat,v0,v1,v2,v3) printf(pat, v0, v1, v2, v3) #define ZAPHOD32_WARN3(pat,v0,v1,v2) printf(pat, v0, v1, v2) #define ZAPHOD32_WARN2(pat,v0,v1) printf(pat, v0, v1) #define NOTE3(pat,v0,v1,v2) printf(pat, v0, v1, v2) #elif DEBUG_ZAPHOD32_HASH == 2 #define ZAPHOD32_WARN6(pat,v0,v1,v2,v3,v4,v5) #define ZAPHOD32_WARN5(pat,v0,v1,v2,v3,v4) #define ZAPHOD32_WARN4(pat,v0,v1,v2,v3) #define ZAPHOD32_WARN3(pat,v0,v1,v2) #define ZAPHOD32_WARN2(pat,v0,v1) #define NOTE3(pat,v0,v1,v2) printf(pat, v0, v1, v2) #else #define ZAPHOD32_WARN6(pat,v0,v1,v2,v3,v4,v5) #define ZAPHOD32_WARN5(pat,v0,v1,v2,v3,v4) #define ZAPHOD32_WARN4(pat,v0,v1,v2,v3) #define ZAPHOD32_WARN3(pat,v0,v1,v2) #define NOTE3(pat,v0,v1,v2) #define ZAPHOD32_WARN2(pat,v0,v1) #endif /* Find best way to ROTL32/ROTL64 */ #ifndef ROTL32 #if defined(_MSC_VER) #include <stdlib.h> /* Microsoft put _rotl declaration in here */ #define ROTL32(x,r) _rotl(x,r) #define ROTR32(x,r) _rotr(x,r) #else /* gcc recognises this code and generates a rotate instruction for CPUs with one */ #define ROTL32(x,r) (((U32)(x) << (r)) | ((U32)(x) >> (32 - (r)))) #define ROTR32(x,r) (((U32)(x) << (32 - (r))) | ((U32)(x) >> (r))) #endif #endif #ifndef PERL_SEEN_HV_FUNC_H_ #if !defined(U64) #include <stdint.h> #define U64 uint64_t #endif #if !defined(U32) #define U32 uint32_t #endif #if !defined(U8) #define U8 unsigned char #endif #if !defined(U16) #define U16 uint16_t #endif #ifndef STRLEN #define STRLEN int #endif #endif #ifndef ZAPHOD32_STATIC_INLINE #ifdef PERL_STATIC_INLINE #define ZAPHOD32_STATIC_INLINE PERL_STATIC_INLINE #else #define ZAPHOD32_STATIC_INLINE static inline #endif #endif #ifndef STMT_START #define STMT_START do #define STMT_END while(0) #endif /* This is two marsaglia xor-shift permutes, with a prime-multiple * sandwiched inside. The end result of doing this twice with different * primes is a completely avalanched v. */ #define ZAPHOD32_SCRAMBLE32(v,prime) STMT_START { \ v ^= (v>>9); \ v ^= (v<<21); \ v ^= (v>>16); \ v *= prime; \ v ^= (v>>17); \ v ^= (v<<15); \ v ^= (v>>23); \ } STMT_END #define ZAPHOD32_FINALIZE(v0,v1,v2) STMT_START { \ ZAPHOD32_WARN3("v0=%08x v1=%08x v2=%08x - ZAPHOD32 FINALIZE\n", \ (unsigned int)v0, (unsigned int)v1, (unsigned int)v2); \ v2 += v0; \ v1 -= v2; \ v1 = ROTL32(v1, 6); \ v2 ^= v1; \ v2 = ROTL32(v2, 28); \ v1 ^= v2; \ v0 += v1; \ v1 = ROTL32(v1, 24); \ v2 += v1; \ v2 = ROTL32(v2, 18) + v1; \ v0 ^= v2; \ v0 = ROTL32(v0, 20); \ v2 += v0; \ v1 ^= v2; \ v0 += v1; \ v0 = ROTL32(v0, 5); \ v2 += v0; \ v2 = ROTL32(v2, 22); \ v0 -= v1; \ v1 -= v2; \ v1 = ROTL32(v1, 17); \ } STMT_END #define ZAPHOD32_MIX(v0,v1,v2,text) STMT_START { \ ZAPHOD32_WARN4("v0=%08x v1=%08x v2=%08x - ZAPHOD32 %s MIX\n", \ (unsigned int)v0,(unsigned int)v1,(unsigned int)v2, text ); \ v0 = ROTL32(v0,16) - v2; \ v1 = ROTR32(v1,13) ^ v2; \ v2 = ROTL32(v2,17) + v1; \ v0 = ROTR32(v0, 2) + v1; \ v1 = ROTR32(v1,17) - v0; \ v2 = ROTR32(v2, 7) ^ v0; \ } STMT_END ZAPHOD32_STATIC_INLINE void zaphod32_seed_state ( const U8 *seed_ch, U8 *state_ch ) { const U32 *seed= (const U32 *)seed_ch; U32 *state= (U32 *)state_ch; /* hex expansion of pi, skipping first two digits. pi= 3.2[43f6...]*/ /* pi value in hex from here: * http://turner.faculty.swau.edu/mathematics/materialslibrary/pi/pibases.html*/ /* Ensure that the three state vectors are nonzero regardless of the seed. */ /* The idea of these two steps is to ensure that the 0 state comes from a seed * utterly unlike that of the value we replace it with.*/ state[0]= seed[0] ^ 0x43f6a888; state[1]= seed[1] ^ 0x5a308d31; state[2]= seed[2] ^ 0x3198a2e0; if (!state[0]) state[0] = 1; if (!state[1]) state[1] = 2; if (!state[2]) state[2] = 4; /* these are pseudo-randomly selected primes between 2**31 and 2**32 * (I generated a big list and then randomly chose some from the list) */ ZAPHOD32_SCRAMBLE32(state[0],0x9fade23b); ZAPHOD32_SCRAMBLE32(state[1],0xaa6f908d); ZAPHOD32_SCRAMBLE32(state[2],0xcdf6b72d); /* now that we have scrambled we do some mixing to avalanche the * state bits to gether */ ZAPHOD32_MIX(state[0],state[1],state[2],"ZAPHOD32 SEED-STATE A 1/4"); ZAPHOD32_MIX(state[0],state[1],state[2],"ZAPHOD32 SEED-STATE A 2/4"); ZAPHOD32_MIX(state[0],state[1],state[2],"ZAPHOD32 SEED-STATE A 3/4"); ZAPHOD32_MIX(state[0],state[1],state[2],"ZAPHOD32 SEED-STATE A 4/4"); /* and then scramble them again with different primes */ ZAPHOD32_SCRAMBLE32(state[0],0xc95d22a9); ZAPHOD32_SCRAMBLE32(state[1],0x8497242b); ZAPHOD32_SCRAMBLE32(state[2],0x9c5cc4e9); /* and a thorough final mix */ ZAPHOD32_MIX(state[0],state[1],state[2],"ZAPHOD32 SEED-STATE B 1/5"); ZAPHOD32_MIX(state[0],state[1],state[2],"ZAPHOD32 SEED-STATE B 2/5"); ZAPHOD32_MIX(state[0],state[1],state[2],"ZAPHOD32 SEED-STATE B 3/5"); ZAPHOD32_MIX(state[0],state[1],state[2],"ZAPHOD32 SEED-STATE B 4/5"); ZAPHOD32_MIX(state[0],state[1],state[2],"ZAPHOD32 SEED-STATE B 5/5"); } ZAPHOD32_STATIC_INLINE U32 zaphod32_hash_with_state( const U8 *state_ch, const U8 *key, const STRLEN key_len ) { U32 *state= (U32 *)state_ch; const U8 *end; STRLEN len = key_len; U32 v0= state[0]; U32 v1= state[1]; U32 v2= state[2] ^ (0xC41A7AB1 * ((U32)key_len + 1)); ZAPHOD32_WARN4("v0=%08x v1=%08x v2=%08x ln=%08x HASH START\n", (unsigned int)state[0], (unsigned int)state[1], (unsigned int)state[2], (unsigned int)key_len); { switch (len) { default: goto zaphod32_read8; case 12: v2 += (U32)key[11] << 24; /* FALLTHROUGH */ case 11: v2 += (U32)key[10] << 16; /* FALLTHROUGH */ case 10: v2 += (U32)U8TO16_LE(key+8); v1 -= U8TO32_LE(key+4); v0 += U8TO32_LE(key+0); goto zaphod32_finalize; case 9: v2 += (U32)key[8]; /* FALLTHROUGH */ case 8: v1 -= U8TO32_LE(key+4); v0 += U8TO32_LE(key+0); goto zaphod32_finalize; case 7: v2 += (U32)key[6]; /* FALLTHROUGH */ case 6: v0 += (U32)U8TO16_LE(key+4); v1 -= U8TO32_LE(key+0); goto zaphod32_finalize; case 5: v0 += (U32)key[4]; /* FALLTHROUGH */ case 4: v1 -= U8TO32_LE(key+0); goto zaphod32_finalize; case 3: v2 += (U32)key[2]; /* FALLTHROUGH */ case 2: v0 += (U32)U8TO16_LE(key); break; case 1: v0 += (U32)key[0]; break; case 0: v2 ^= 0xFF; break; } v0 -= v2; v2 = ROTL32(v2, 8) ^ v0; v0 = ROTR32(v0,16) + v2; v2 += v0; v0 += v0 >> 9; v0 += v2; v2 ^= v0; v2 += v2 << 4; v0 -= v2; v2 = ROTR32(v2, 8) ^ v0; v0 = ROTL32(v0,16) ^ v2; v2 = ROTL32(v2,10) + v0; v0 = ROTR32(v0,30) + v2; v2 = ROTR32(v2,12); return v0 ^ v2; } /* if (len >= 8) */ /* this block is only reached by a goto above, so this condition is commented out, but if the above block is removed it would be necessary to use this. */ { zaphod32_read8: len = key_len & 0x7; end = key + key_len - len; do { v1 -= U8TO32_LE(key+0); v0 += U8TO32_LE(key+4); ZAPHOD32_MIX(v0,v1,v2,"MIX 2-WORDS A"); key += 8; } while ( key < end ); } if ( len >= 4 ) { v1 -= U8TO32_LE(key); key += 4; } v0 += (U32)(key_len) << 24; switch (len & 0x3) { case 3: v2 += (U32)key[2]; /* FALLTHROUGH */ case 2: v0 += (U32)U8TO16_LE(key); break; case 1: v0 += (U32)key[0]; break; case 0: v2 ^= 0xFF; break; } zaphod32_finalize: ZAPHOD32_FINALIZE(v0,v1,v2); ZAPHOD32_WARN4("v0=%08x v1=%08x v2=%08x hh=%08x - FINAL\n\n", (unsigned int)v0, (unsigned int)v1, (unsigned int)v2, (unsigned int)v0 ^ v1 ^ v2); return v0 ^ v1 ^ v2; } ZAPHOD32_STATIC_INLINE U32 zaphod32_hash( const U8 *seed_ch, const U8 *key, const STRLEN key_len ) { U32 state[3]; zaphod32_seed_state(seed_ch,(U8*)state); return zaphod32_hash_with_state((U8*)state,key,key_len); } #endif