//-----------------------------------------------------------------------------

// MurmurHash3 was written by Austin Appleby, and is placed in the public

// domain. The author hereby disclaims copyright to this source code.

// Note - The x86 and x64 versions do _not_ produce the same results, as the

// algorithms are optimized for their respective platforms. You can still

// compile and run any of them on any platform, but your performance with the

// non-native version will be less than optimal.

#include "murmur_hash3.h"

#include "vec/common/unaligned.h"

//-----------------------------------------------------------------------------

// Platform-specific functions and macros

// Microsoft Visual Studio

#include "common/compile_check_begin.h"

#if defined(_MSC_VER)

#define FORCE_INLINE __forceinline

#include <stdlib.h>

#define ROTL32(x, y) _rotl(x, y)

#define ROTL64(x, y) _rotl64(x, y)

#define BIG_CONSTANT(x) (x)

// Other compilers

#else // defined(_MSC_VER)

#define FORCE_INLINE inline __attribute__((always_inline))

FORCE_INLINE uint32_t rotl32(uint32_t x, int8_t r) {

    return (x << r) | (x >> (32 - r));

}

FORCE_INLINE uint64_t rotl64(uint64_t x, int8_t r) {

    return (x << r) | (x >> (64 - r));

}

#define ROTL32(x, y) rotl32(x, y)

#define ROTL64(x, y) rotl64(x, y)

#define BIG_CONSTANT(x) (x##LLU)

#endif // !defined(_MSC_VER)

//-----------------------------------------------------------------------------

// Block read - if your platform needs to do endian-swapping or can only

// handle aligned reads, do the conversion here

FORCE_INLINE uint32_t getblock32(const uint32_t* p, int i) {

    return unaligned_load<uint32_t>(&p[i]);

}

FORCE_INLINE uint64_t getblock64(const uint64_t* p, int i) {

    return unaligned_load<uint64_t>(&p[i]);

}

//-----------------------------------------------------------------------------

// Finalization mix - force all bits of a hash block to avalanche

FORCE_INLINE uint32_t fmix32(uint32_t h) {

    h ^= h >> 16;

    h *= 0x85ebca6b;

    h ^= h >> 13;

    h *= 0xc2b2ae35;

    h ^= h >> 16;

    return h;

}

//----------

FORCE_INLINE uint64_t fmix64(uint64_t k) {

    k ^= k >> 33;

    k *= BIG_CONSTANT(0xff51afd7ed558ccd);

    k ^= k >> 33;

    k *= BIG_CONSTANT(0xc4ceb9fe1a85ec53);

    k ^= k >> 33;

    return k;

}

//-----------------------------------------------------------------------------

void murmur_hash3_x86_32(const void* key, int64_t len, uint32_t seed, void* out) {

    const uint8_t* data = (const uint8_t*)key;

    const int nblocks = (int)len / 4;

    uint32_t h1 = seed;

    const uint32_t c1 = 0xcc9e2d51;

    const uint32_t c2 = 0x1b873593;

    //----------

    // body

    const uint32_t* blocks = (const uint32_t*)(data + nblocks * 4);

    for (int i = -nblocks; i; i++) {

        uint32_t k1 = getblock32(blocks, i);

        k1 *= c1;

        k1 = ROTL32(k1, 15);

        k1 *= c2;

        h1 ^= k1;

        h1 = ROTL32(h1, 13);

        h1 = h1 * 5 + 0xe6546b64;

    }

    //----------

    // tail

    const uint8_t* tail = (const uint8_t*)(data + nblocks * 4);

    uint32_t k1 = 0;

    switch (len & 3) {

    case 3:

        k1 ^= tail[2] << 16;

        [[fallthrough]];

    case 2:

        k1 ^= tail[1] << 8;

        [[fallthrough]];

    case 1:

        k1 ^= tail[0];

        k1 *= c1;

        k1 = ROTL32(k1, 15);

        k1 *= c2;

        h1 ^= k1;

    };

    //----------

    // finalization

    h1 ^= len;

    h1 = fmix32(h1);

    *(uint32_t*)out = h1;

}

//-----------------------------------------------------------------------------

void murmur_hash3_x86_128(const void* key, const int len, uint32_t seed, void* out) {

    const uint8_t* data = (const uint8_t*)key;

    const int nblocks = len / 16;

    uint32_t h1 = seed;

    uint32_t h2 = seed;

    uint32_t h3 = seed;

    uint32_t h4 = seed;

    const uint32_t c1 = 0x239b961b;

    const uint32_t c2 = 0xab0e9789;

    const uint32_t c3 = 0x38b34ae5;

    const uint32_t c4 = 0xa1e38b93;

    //----------

    // body

    const uint32_t* blocks = (const uint32_t*)(data + nblocks * 16);

    for (int i = -nblocks; i; i++) {

        uint32_t k1 = getblock32(blocks, i * 4 + 0);

        uint32_t k2 = getblock32(blocks, i * 4 + 1);

        uint32_t k3 = getblock32(blocks, i * 4 + 2);

        uint32_t k4 = getblock32(blocks, i * 4 + 3);

        k1 *= c1;

        k1 = ROTL32(k1, 15);

        k1 *= c2;

        h1 ^= k1;

        h1 = ROTL32(h1, 19);

        h1 += h2;

        h1 = h1 * 5 + 0x561ccd1b;

        k2 *= c2;

        k2 = ROTL32(k2, 16);

        k2 *= c3;

        h2 ^= k2;

        h2 = ROTL32(h2, 17);

        h2 += h3;

        h2 = h2 * 5 + 0x0bcaa747;

        k3 *= c3;

        k3 = ROTL32(k3, 17);

        k3 *= c4;

        h3 ^= k3;

        h3 = ROTL32(h3, 15);

        h3 += h4;

        h3 = h3 * 5 + 0x96cd1c35;

        k4 *= c4;

        k4 = ROTL32(k4, 18);

        k4 *= c1;

        h4 ^= k4;

        h4 = ROTL32(h4, 13);

        h4 += h1;

        h4 = h4 * 5 + 0x32ac3b17;

    }

    //----------

    // tail

    const uint8_t* tail = (const uint8_t*)(data + nblocks * 16);

    uint32_t k1 = 0;

    uint32_t k2 = 0;

    uint32_t k3 = 0;

    uint32_t k4 = 0;

    switch (len & 15) {

    case 15:

        k4 ^= tail[14] << 16;

        [[fallthrough]];

    case 14:

        k4 ^= tail[13] << 8;

        [[fallthrough]];

    case 13:

        k4 ^= tail[12] << 0;

        k4 *= c4;

        k4 = ROTL32(k4, 18);

        k4 *= c1;

        h4 ^= k4;

        [[fallthrough]];

    case 12:

        k3 ^= tail[11] << 24;

        [[fallthrough]];

    case 11:

        k3 ^= tail[10] << 16;

        [[fallthrough]];

    case 10:

        k3 ^= tail[9] << 8;

        [[fallthrough]];

    case 9:

        k3 ^= tail[8] << 0;

        k3 *= c3;

        k3 = ROTL32(k3, 17);

        k3 *= c4;

        h3 ^= k3;

        [[fallthrough]];

    case 8:

        k2 ^= tail[7] << 24;

        [[fallthrough]];

    case 7:

        k2 ^= tail[6] << 16;

        [[fallthrough]];

    case 6:

        k2 ^= tail[5] << 8;

        [[fallthrough]];

    case 5:

        k2 ^= tail[4] << 0;

        k2 *= c2;

        k2 = ROTL32(k2, 16);

        k2 *= c3;

        h2 ^= k2;

        [[fallthrough]];

    case 4:

        k1 ^= tail[3] << 24;

        [[fallthrough]];

    case 3:

        k1 ^= tail[2] << 16;

        [[fallthrough]];

    case 2:

        k1 ^= tail[1] << 8;

        [[fallthrough]];

    case 1:

        k1 ^= tail[0] << 0;

        k1 *= c1;

        k1 = ROTL32(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 = fmix32(h1);

    h2 = fmix32(h2);

    h3 = fmix32(h3);

    h4 = fmix32(h4);

    h1 += h2;

    h1 += h3;

    h1 += h4;

    h2 += h1;

    h3 += h1;

    h4 += h1;

    ((uint32_t*)out)[0] = h1;

    ((uint32_t*)out)[1] = h2;

    ((uint32_t*)out)[2] = h3;

    ((uint32_t*)out)[3] = h4;

}

//-----------------------------------------------------------------------------

void murmur_hash3_x64_128(const void* key, const int len, const uint32_t seed, void* out) {

    const uint8_t* data = (const uint8_t*)key;

    const int nblocks = len / 16;

    uint64_t h1 = seed;

    uint64_t h2 = seed;

    const uint64_t c1 = BIG_CONSTANT(0x87c37b91114253d5);

    const uint64_t c2 = BIG_CONSTANT(0x4cf5ad432745937f);

    //----------

    // body

    const uint64_t* blocks = (const uint64_t*)(data);

    for (int i = 0; i < nblocks; i++) {

        uint64_t k1 = getblock64(blocks, i * 2 + 0);

        uint64_t k2 = getblock64(blocks, i * 2 + 1);

        k1 *= c1;

        k1 = ROTL64(k1, 31);

        k1 *= c2;

        h1 ^= k1;

        h1 = ROTL64(h1, 27);

        h1 += h2;

        h1 = h1 * 5 + 0x52dce729;

        k2 *= c2;

        k2 = ROTL64(k2, 33);

        k2 *= c1;

        h2 ^= k2;

        h2 = ROTL64(h2, 31);

        h2 += h1;

        h2 = h2 * 5 + 0x38495ab5;

    }

    //----------

    // tail

    const uint8_t* tail = (const uint8_t*)(data + nblocks * 16);

    uint64_t k1 = 0;

    uint64_t k2 = 0;

    switch (len & 15) {

    case 15:

        k2 ^= ((uint64_t)tail[14]) << 48;

        [[fallthrough]];

    case 14:

        k2 ^= ((uint64_t)tail[13]) << 40;

        [[fallthrough]];

    case 13:

        k2 ^= ((uint64_t)tail[12]) << 32;

        [[fallthrough]];

    case 12:

        k2 ^= ((uint64_t)tail[11]) << 24;

        [[fallthrough]];

    case 11:

        k2 ^= ((uint64_t)tail[10]) << 16;

        [[fallthrough]];

    case 10:

        k2 ^= ((uint64_t)tail[9]) << 8;

        [[fallthrough]];

    case 9:

        k2 ^= ((uint64_t)tail[8]) << 0;

        k2 *= c2;

        k2 = ROTL64(k2, 33);

        k2 *= c1;

        h2 ^= k2;

        [[fallthrough]];

    case 8:

        k1 ^= ((uint64_t)tail[7]) << 56;

        [[fallthrough]];

    case 7:

        k1 ^= ((uint64_t)tail[6]) << 48;

        [[fallthrough]];

    case 6:

        k1 ^= ((uint64_t)tail[5]) << 40;

        [[fallthrough]];

    case 5:

        k1 ^= ((uint64_t)tail[4]) << 32;

        [[fallthrough]];

    case 4:

        k1 ^= ((uint64_t)tail[3]) << 24;

        [[fallthrough]];

    case 3:

        k1 ^= ((uint64_t)tail[2]) << 16;

        [[fallthrough]];

    case 2:

        k1 ^= ((uint64_t)tail[1]) << 8;

        [[fallthrough]];

    case 1:

        k1 ^= ((uint64_t)tail[0]) << 0;

        k1 *= c1;

        k1 = ROTL64(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;

    ((uint64_t*)out)[0] = h1;

    ((uint64_t*)out)[1] = h2;

}

void murmur_hash3_x64_64(const void* key, const int64_t len, const uint64_t seed, void* out) {

    const uint8_t* data = (const uint8_t*)key;

    const int nblocks = (int)len / 8;

    uint64_t h1 = seed;

    const uint64_t c1 = BIG_CONSTANT(0x87c37b91114253d5);

    const uint64_t c2 = BIG_CONSTANT(0x4cf5ad432745937f);

    //----------

    // body

    const uint64_t* blocks = (const uint64_t*)(data);

    for (int i = 0; i < nblocks; i++) {

        uint64_t k1 = getblock64(blocks, i);

        k1 *= c1;

        k1 = ROTL64(k1, 31);

        k1 *= c2;

        h1 ^= k1;

        h1 = ROTL64(h1, 27);

        h1 = h1 * 5 + 0x52dce729;

    }

    //----------

    // tail

    const uint8_t* tail = (const uint8_t*)(data + nblocks * 8);

    uint64_t k1 = 0;

    switch (len & 7) {

    case 7:

        k1 ^= ((uint64_t)tail[6]) << 48;

        [[fallthrough]];

    case 6:

        k1 ^= ((uint64_t)tail[5]) << 40;

        [[fallthrough]];

    case 5:

        k1 ^= ((uint64_t)tail[4]) << 32;

        [[fallthrough]];

    case 4:

        k1 ^= ((uint64_t)tail[3]) << 24;

        [[fallthrough]];

    case 3:

        k1 ^= ((uint64_t)tail[2]) << 16;

        [[fallthrough]];

    case 2:

        k1 ^= ((uint64_t)tail[1]) << 8;

        [[fallthrough]];

    case 1:

        k1 ^= ((uint64_t)tail[0]) << 0;

        k1 *= c1;

        k1 = ROTL64(k1, 31);

        k1 *= c2;

        h1 ^= k1;

    };

    //----------

    // finalization

    h1 ^= len;

    h1 = fmix64(h1);

    ((uint64_t*)out)[0] = h1;

}

#include "common/compile_check_end.h"

//-----------------------------------------------------------------------------