tzhash/tz/avx2.go
Evgenii Stratonikov 1520cde665 tz: fix package comments
Signed-off-by: Evgenii Stratonikov <evgeniy@nspcc.ru>
2022-02-25 14:53:59 +03:00

62 lines
1.5 KiB
Go

package tz
import (
"hash"
"github.com/nspcc-dev/tzhash/gf127/avx2"
)
type digest2 struct {
x [2]avx2.GF127x2
}
// type assertion
var _ hash.Hash = (*digest2)(nil)
func newAVX2() *digest2 {
d := new(digest2)
d.Reset()
return d
}
func (d *digest2) Write(data []byte) (n int, err error) {
n = len(data)
for _, b := range data {
mulBitRightx2(&d.x[0], &d.x[1], &minmax[(b>>7)&1])
mulBitRightx2(&d.x[0], &d.x[1], &minmax[(b>>6)&1])
mulBitRightx2(&d.x[0], &d.x[1], &minmax[(b>>5)&1])
mulBitRightx2(&d.x[0], &d.x[1], &minmax[(b>>4)&1])
mulBitRightx2(&d.x[0], &d.x[1], &minmax[(b>>3)&1])
mulBitRightx2(&d.x[0], &d.x[1], &minmax[(b>>2)&1])
mulBitRightx2(&d.x[0], &d.x[1], &minmax[(b>>1)&1])
mulBitRightx2(&d.x[0], &d.x[1], &minmax[(b>>0)&1])
}
return
}
func (d *digest2) Sum(in []byte) []byte {
// Make a copy of d so that caller can keep writing and summing.
d0 := *d
h := d0.checkSum()
return append(in, h[:]...)
}
func (d *digest2) Reset() {
d.x[0] = avx2.GF127x2{GF127{1, 0}, GF127{0, 0}}
d.x[1] = avx2.GF127x2{GF127{0, 0}, GF127{1, 0}}
}
func (d *digest2) Size() int { return Size }
func (d *digest2) BlockSize() int { return hashBlockSize }
func (d *digest2) checkSum() (b [Size]byte) {
// Matrix is stored transposed,
// but we need to use order consistent with digest.
h := d.x[0].ByteArray()
copy(b[:], h[:16])
copy(b[32:], h[16:])
h = d.x[1].ByteArray()
copy(b[16:], h[:16])
copy(b[48:], h[16:])
return
}
func mulBitRightx2(c00c10 *avx2.GF127x2, c01c11 *avx2.GF127x2, e *GF127)