mirror of
https://github.com/superseriousbusiness/gotosocial.git
synced 2024-12-29 02:26:31 +00:00
135 lines
4.3 KiB
Go
135 lines
4.3 KiB
Go
package xxh3
|
|
|
|
import "math/bits"
|
|
|
|
// HashSeed returns the hash of the byte slice with given seed.
|
|
func HashSeed(b []byte, seed uint64) uint64 {
|
|
return hashAnySeed(*(*str)(ptr(&b)), seed)
|
|
|
|
}
|
|
|
|
// HashStringSeed returns the hash of the string slice with given seed.
|
|
func HashStringSeed(s string, seed uint64) uint64 {
|
|
return hashAnySeed(*(*str)(ptr(&s)), seed)
|
|
}
|
|
|
|
func hashAnySeed(s str, seed uint64) (acc u64) {
|
|
p, l := s.p, s.l
|
|
|
|
switch {
|
|
case l <= 16:
|
|
switch {
|
|
case l > 8:
|
|
inputlo := readU64(p, 0) ^ (key64_024 ^ key64_032 + seed)
|
|
inputhi := readU64(p, ui(l)-8) ^ (key64_040 ^ key64_048 - seed)
|
|
folded := mulFold64(inputlo, inputhi)
|
|
return xxh3Avalanche(u64(l) + bits.ReverseBytes64(inputlo) + inputhi + folded)
|
|
|
|
case l > 3:
|
|
seed ^= u64(bits.ReverseBytes32(u32(seed))) << 32
|
|
input1 := readU32(p, 0)
|
|
input2 := readU32(p, ui(l)-4)
|
|
input64 := u64(input2) + u64(input1)<<32
|
|
keyed := input64 ^ (key64_008 ^ key64_016 - seed)
|
|
return rrmxmx(keyed, u64(l))
|
|
|
|
case l == 3: // 3
|
|
c12 := u64(readU16(p, 0))
|
|
c3 := u64(readU8(p, 2))
|
|
acc = c12<<16 + c3 + 3<<8
|
|
|
|
case l > 1: // 2
|
|
c12 := u64(readU16(p, 0))
|
|
acc = c12*(1<<24+1)>>8 + 2<<8
|
|
|
|
case l == 1: // 1
|
|
c1 := u64(readU8(p, 0))
|
|
acc = c1*(1<<24+1<<16+1) + 1<<8
|
|
|
|
default:
|
|
return xxhAvalancheSmall(seed ^ key64_056 ^ key64_064)
|
|
}
|
|
|
|
acc ^= u64(key32_000^key32_004) + seed
|
|
return xxhAvalancheSmall(acc)
|
|
|
|
case l <= 128:
|
|
acc = u64(l) * prime64_1
|
|
|
|
if l > 32 {
|
|
if l > 64 {
|
|
if l > 96 {
|
|
acc += mulFold64(readU64(p, 6*8)^(key64_096+seed), readU64(p, 7*8)^(key64_104-seed))
|
|
acc += mulFold64(readU64(p, ui(l)-8*8)^(key64_112+seed), readU64(p, ui(l)-7*8)^(key64_120-seed))
|
|
} // 96
|
|
acc += mulFold64(readU64(p, 4*8)^(key64_064+seed), readU64(p, 5*8)^(key64_072-seed))
|
|
acc += mulFold64(readU64(p, ui(l)-6*8)^(key64_080+seed), readU64(p, ui(l)-5*8)^(key64_088-seed))
|
|
} // 64
|
|
acc += mulFold64(readU64(p, 2*8)^(key64_032+seed), readU64(p, 3*8)^(key64_040-seed))
|
|
acc += mulFold64(readU64(p, ui(l)-4*8)^(key64_048+seed), readU64(p, ui(l)-3*8)^(key64_056-seed))
|
|
} // 32
|
|
acc += mulFold64(readU64(p, 0*8)^(key64_000+seed), readU64(p, 1*8)^(key64_008-seed))
|
|
acc += mulFold64(readU64(p, ui(l)-2*8)^(key64_016+seed), readU64(p, ui(l)-1*8)^(key64_024-seed))
|
|
|
|
return xxh3Avalanche(acc)
|
|
|
|
case l <= 240:
|
|
acc = u64(l) * prime64_1
|
|
|
|
acc += mulFold64(readU64(p, 0*16+0)^(key64_000+seed), readU64(p, 0*16+8)^(key64_008-seed))
|
|
acc += mulFold64(readU64(p, 1*16+0)^(key64_016+seed), readU64(p, 1*16+8)^(key64_024-seed))
|
|
acc += mulFold64(readU64(p, 2*16+0)^(key64_032+seed), readU64(p, 2*16+8)^(key64_040-seed))
|
|
acc += mulFold64(readU64(p, 3*16+0)^(key64_048+seed), readU64(p, 3*16+8)^(key64_056-seed))
|
|
acc += mulFold64(readU64(p, 4*16+0)^(key64_064+seed), readU64(p, 4*16+8)^(key64_072-seed))
|
|
acc += mulFold64(readU64(p, 5*16+0)^(key64_080+seed), readU64(p, 5*16+8)^(key64_088-seed))
|
|
acc += mulFold64(readU64(p, 6*16+0)^(key64_096+seed), readU64(p, 6*16+8)^(key64_104-seed))
|
|
acc += mulFold64(readU64(p, 7*16+0)^(key64_112+seed), readU64(p, 7*16+8)^(key64_120-seed))
|
|
|
|
// avalanche
|
|
acc = xxh3Avalanche(acc)
|
|
|
|
// trailing groups after 128
|
|
top := ui(l) &^ 15
|
|
for i := ui(8 * 16); i < top; i += 16 {
|
|
acc += mulFold64(readU64(p, i+0)^(readU64(key, i-125)+seed), readU64(p, i+8)^(readU64(key, i-117)-seed))
|
|
}
|
|
|
|
// last 16 bytes
|
|
acc += mulFold64(readU64(p, ui(l)-16)^(key64_119+seed), readU64(p, ui(l)-8)^(key64_127-seed))
|
|
|
|
return xxh3Avalanche(acc)
|
|
|
|
default:
|
|
acc = u64(l) * prime64_1
|
|
|
|
secret := key
|
|
if seed != 0 {
|
|
secret = ptr(&[secretSize]byte{})
|
|
initSecret(secret, seed)
|
|
}
|
|
|
|
accs := [8]u64{
|
|
prime32_3, prime64_1, prime64_2, prime64_3,
|
|
prime64_4, prime32_2, prime64_5, prime32_1,
|
|
}
|
|
|
|
if hasAVX512 && l >= avx512Switch {
|
|
accumAVX512(&accs, p, secret, u64(l))
|
|
} else if hasAVX2 {
|
|
accumAVX2(&accs, p, secret, u64(l))
|
|
} else if hasSSE2 {
|
|
accumSSE(&accs, p, secret, u64(l))
|
|
} else {
|
|
accumScalarSeed(&accs, p, secret, u64(l))
|
|
}
|
|
|
|
// merge accs
|
|
acc += mulFold64(accs[0]^readU64(secret, 11), accs[1]^readU64(secret, 19))
|
|
acc += mulFold64(accs[2]^readU64(secret, 27), accs[3]^readU64(secret, 35))
|
|
acc += mulFold64(accs[4]^readU64(secret, 43), accs[5]^readU64(secret, 51))
|
|
acc += mulFold64(accs[6]^readU64(secret, 59), accs[7]^readU64(secret, 67))
|
|
|
|
return xxh3Avalanche(acc)
|
|
}
|
|
}
|