dolphin/Source/Core/Common/Hash.cpp
2023-11-28 23:03:26 +11:00

450 lines
8.5 KiB
C++

// Copyright 2008 Dolphin Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later
#include "Common/Hash.h"
#include <algorithm>
#include <bit>
#include <cstring>
#include <zlib.h>
#include "Common/BitUtils.h"
#include "Common/CPUDetect.h"
#include "Common/CommonFuncs.h"
#include "Common/Intrinsics.h"
#ifdef _M_ARM_64
#ifdef _MSC_VER
#include <intrin.h>
#else
#include <arm_acle.h>
#endif
#endif
namespace Common
{
u32 HashAdler32(const u8* data, size_t len)
{
// Use fast implementation from zlib-ng
return adler32_z(1, data, len);
}
// Stupid hash - but can't go back now :)
// Don't use for new things. At least it's reasonably fast.
u32 HashEctor(const u8* data, size_t len)
{
u32 crc = 0;
for (size_t i = 0; i < len; i++)
{
crc ^= data[i];
crc = (crc << 3) | (crc >> 29);
}
return crc;
}
#ifdef _ARCH_64
//-----------------------------------------------------------------------------
// Block read - if your platform needs to do endian-swapping or can only
// handle aligned reads, do the conversion here
static u64 getblock(const u64* p, int i)
{
return p[i];
}
//----------
// Block mix - combine the key bits with the hash bits and scramble everything
static void bmix64(u64& h1, u64& h2, u64& k1, u64& k2, u64& c1, u64& c2)
{
k1 *= c1;
k1 = std::rotl(k1, 23);
k1 *= c2;
h1 ^= k1;
h1 += h2;
h2 = std::rotl(h2, 41);
k2 *= c2;
k2 = std::rotl(k2, 23);
k2 *= c1;
h2 ^= k2;
h2 += h1;
h1 = h1 * 3 + 0x52dce729;
h2 = h2 * 3 + 0x38495ab5;
c1 = c1 * 5 + 0x7b7d159c;
c2 = c2 * 5 + 0x6bce6396;
}
//----------
// Finalization mix - avalanches all bits to within 0.05% bias
static u64 fmix64(u64 k)
{
k ^= k >> 33;
k *= 0xff51afd7ed558ccd;
k ^= k >> 33;
k *= 0xc4ceb9fe1a85ec53;
k ^= k >> 33;
return k;
}
static u64 GetMurmurHash3(const u8* src, u32 len, u32 samples)
{
const u8* data = (const u8*)src;
const int nblocks = len / 16;
u32 Step = (len / 8);
if (samples == 0)
samples = std::max(Step, 1u);
Step = Step / samples;
if (Step < 1)
Step = 1;
u64 h1 = 0x9368e53c2f6af274;
u64 h2 = 0x586dcd208f7cd3fd;
u64 c1 = 0x87c37b91114253d5;
u64 c2 = 0x4cf5ad432745937f;
//----------
// body
const u64* blocks = (const u64*)(data);
for (int i = 0; i < nblocks; i += Step)
{
u64 k1 = getblock(blocks, i * 2 + 0);
u64 k2 = getblock(blocks, i * 2 + 1);
bmix64(h1, h2, k1, k2, c1, c2);
}
//----------
// tail
const u8* tail = (const u8*)(data + nblocks * 16);
u64 k1 = 0;
u64 k2 = 0;
switch (len & 15)
{
case 15:
k2 ^= u64(tail[14]) << 48;
case 14:
k2 ^= u64(tail[13]) << 40;
case 13:
k2 ^= u64(tail[12]) << 32;
case 12:
k2 ^= u64(tail[11]) << 24;
case 11:
k2 ^= u64(tail[10]) << 16;
case 10:
k2 ^= u64(tail[9]) << 8;
case 9:
k2 ^= u64(tail[8]) << 0;
case 8:
k1 ^= u64(tail[7]) << 56;
case 7:
k1 ^= u64(tail[6]) << 48;
case 6:
k1 ^= u64(tail[5]) << 40;
case 5:
k1 ^= u64(tail[4]) << 32;
case 4:
k1 ^= u64(tail[3]) << 24;
case 3:
k1 ^= u64(tail[2]) << 16;
case 2:
k1 ^= u64(tail[1]) << 8;
case 1:
k1 ^= u64(tail[0]) << 0;
bmix64(h1, h2, k1, k2, c1, c2);
};
//----------
// finalization
h2 ^= len;
h1 += h2;
h2 += h1;
h1 = fmix64(h1);
h2 = fmix64(h2);
h1 += h2;
return h1;
}
#else
//-----------------------------------------------------------------------------
// Block read - if your platform needs to do endian-swapping or can only
// handle aligned reads, do the conversion here
static u32 getblock(const u32* p, int i)
{
return p[i];
}
//----------
// Finalization mix - force all bits of a hash block to avalanche
// avalanches all bits to within 0.25% bias
static u32 fmix32(u32 h)
{
h ^= h >> 16;
h *= 0x85ebca6b;
h ^= h >> 13;
h *= 0xc2b2ae35;
h ^= h >> 16;
return h;
}
static void bmix32(u32& h1, u32& h2, u32& k1, u32& k2, u32& c1, u32& c2)
{
k1 *= c1;
k1 = std::rotl(k1, 11);
k1 *= c2;
h1 ^= k1;
h1 += h2;
h2 = std::rotl(h2, 17);
k2 *= c2;
k2 = std::rotl(k2, 11);
k2 *= c1;
h2 ^= k2;
h2 += h1;
h1 = h1 * 3 + 0x52dce729;
h2 = h2 * 3 + 0x38495ab5;
c1 = c1 * 5 + 0x7b7d159c;
c2 = c2 * 5 + 0x6bce6396;
}
//----------
static u64 GetMurmurHash3(const u8* src, u32 len, u32 samples)
{
const u8* data = (const u8*)src;
u32 out[2];
const int nblocks = len / 8;
u32 Step = (len / 4);
if (samples == 0)
samples = std::max(Step, 1u);
Step = Step / samples;
if (Step < 1)
Step = 1;
u32 h1 = 0x8de1c3ac;
u32 h2 = 0xbab98226;
u32 c1 = 0x95543787;
u32 c2 = 0x2ad7eb25;
//----------
// body
const u32* blocks = (const u32*)(data + nblocks * 8);
for (int i = -nblocks; i < 0; i += Step)
{
u32 k1 = getblock(blocks, i * 2 + 0);
u32 k2 = getblock(blocks, i * 2 + 1);
bmix32(h1, h2, k1, k2, c1, c2);
}
//----------
// tail
const u8* tail = (const u8*)(data + nblocks * 8);
u32 k1 = 0;
u32 k2 = 0;
switch (len & 7)
{
case 7:
k2 ^= tail[6] << 16;
case 6:
k2 ^= tail[5] << 8;
case 5:
k2 ^= tail[4] << 0;
case 4:
k1 ^= tail[3] << 24;
case 3:
k1 ^= tail[2] << 16;
case 2:
k1 ^= tail[1] << 8;
case 1:
k1 ^= tail[0] << 0;
bmix32(h1, h2, k1, k2, c1, c2);
};
//----------
// finalization
h2 ^= len;
h1 += h2;
h2 += h1;
h1 = fmix32(h1);
h2 = fmix32(h2);
h1 += h2;
h2 += h1;
out[0] = h1;
out[1] = h2;
return *((u64*)&out);
}
#endif
#if defined(_M_X86_64)
FUNCTION_TARGET_SSE42
static u64 GetHash64_SSE42_CRC32(const u8* src, u32 len, u32 samples)
{
u64 h[4] = {len, 0, 0, 0};
u32 Step = (len / 8);
const u64* data = (const u64*)src;
const u64* end = data + Step;
if (samples == 0)
samples = std::max(Step, 1u);
Step = Step / samples;
if (Step < 1)
Step = 1;
while (data < end - Step * 3)
{
h[0] = _mm_crc32_u64(h[0], data[Step * 0]);
h[1] = _mm_crc32_u64(h[1], data[Step * 1]);
h[2] = _mm_crc32_u64(h[2], data[Step * 2]);
h[3] = _mm_crc32_u64(h[3], data[Step * 3]);
data += Step * 4;
}
if (data < end - Step * 0)
h[0] = _mm_crc32_u64(h[0], data[Step * 0]);
if (data < end - Step * 1)
h[1] = _mm_crc32_u64(h[1], data[Step * 1]);
if (data < end - Step * 2)
h[2] = _mm_crc32_u64(h[2], data[Step * 2]);
if (len & 7)
{
u64 temp = 0;
memcpy(&temp, end, len & 7);
h[0] = _mm_crc32_u64(h[0], temp);
}
// FIXME: is there a better way to combine these partial hashes?
return h[0] + (h[1] << 10) + (h[2] << 21) + (h[3] << 32);
}
#elif defined(_M_ARM_64)
static u64 GetHash64_ARMv8_CRC32(const u8* src, u32 len, u32 samples)
{
u64 h[4] = {len, 0, 0, 0};
u32 Step = (len / 8);
const u64* data = (const u64*)src;
const u64* end = data + Step;
if (samples == 0)
samples = std::max(Step, 1u);
Step = Step / samples;
if (Step < 1)
Step = 1;
while (data < end - Step * 3)
{
h[0] = __crc32d(h[0], data[Step * 0]);
h[1] = __crc32d(h[1], data[Step * 1]);
h[2] = __crc32d(h[2], data[Step * 2]);
h[3] = __crc32d(h[3], data[Step * 3]);
data += Step * 4;
}
if (data < end - Step * 0)
h[0] = __crc32d(h[0], data[Step * 0]);
if (data < end - Step * 1)
h[1] = __crc32d(h[1], data[Step * 1]);
if (data < end - Step * 2)
h[2] = __crc32d(h[2], data[Step * 2]);
if (len & 7)
{
u64 temp = 0;
memcpy(&temp, end, len & 7);
h[0] = __crc32d(h[0], temp);
}
// FIXME: is there a better way to combine these partial hashes?
return h[0] + (h[1] << 10) + (h[2] << 21) + (h[3] << 32);
}
#endif
using TextureHashFunction = u64 (*)(const u8* src, u32 len, u32 samples);
static u64 SetHash64Function(const u8* src, u32 len, u32 samples);
static TextureHashFunction s_texture_hash_func = SetHash64Function;
static u64 SetHash64Function(const u8* src, u32 len, u32 samples)
{
if (cpu_info.bCRC32)
{
#if defined(_M_X86_64)
s_texture_hash_func = &GetHash64_SSE42_CRC32;
#elif defined(_M_ARM_64)
s_texture_hash_func = &GetHash64_ARMv8_CRC32;
#endif
}
else
{
s_texture_hash_func = &GetMurmurHash3;
}
return s_texture_hash_func(src, len, samples);
}
u64 GetHash64(const u8* src, u32 len, u32 samples)
{
return s_texture_hash_func(src, len, samples);
}
u32 StartCRC32()
{
return crc32_z(0L, Z_NULL, 0);
}
u32 UpdateCRC32(u32 crc, const u8* data, size_t len)
{
return crc32_z(crc, data, len);
}
u32 ComputeCRC32(const u8* data, size_t len)
{
return UpdateCRC32(StartCRC32(), data, len);
}
u32 ComputeCRC32(std::string_view data)
{
return ComputeCRC32(reinterpret_cast<const u8*>(data.data()), data.size());
}
} // namespace Common