tzhash/tz/avx2_inline.go
Evgenii Stratonikov 1520cde665 tz: fix package comments
Signed-off-by: Evgenii Stratonikov <evgeniy@nspcc.ru>
2022-02-25 14:53:59 +03:00

55 lines
1.2 KiB
Go

package tz
import (
"hash"
"github.com/nspcc-dev/tzhash/gf127/avx2"
)
type digest3 struct {
x [2]avx2.GF127x2
}
// type assertion
var _ hash.Hash = (*digest3)(nil)
func newAVX2Inline() *digest3 {
d := new(digest3)
d.Reset()
return d
}
func (d *digest3) Write(data []byte) (n int, err error) {
n = len(data)
if len(data) != 0 {
mulByteSliceRightx2(&d.x[0], &d.x[1], n, &data[0])
}
return
}
func (d *digest3) 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 *digest3) 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 *digest3) Size() int { return Size }
func (d *digest3) BlockSize() int { return hashBlockSize }
func (d *digest3) 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 mulByteSliceRightx2(c00c10 *avx2.GF127x2, c01c11 *avx2.GF127x2, n int, data *byte)