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// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build go1.11
// +build !gccgo
package chacha20
const (
haveAsm = true
bufSize = 256
)
//go:noescape
func xorKeyStreamVX(dst, src []byte, key *[8]uint32, nonce *[3]uint32, counter *uint32)
func (c *Cipher) xorKeyStreamAsm(dst, src []byte) {
if len(src) >= bufSize {
xorKeyStreamVX(dst, src, &c.key, &c.nonce, &c.counter)
}
if len(src)%bufSize != 0 {
i := len(src) - len(src)%bufSize
c.buf = [bufSize]byte{}
copy(c.buf[:], src[i:])
xorKeyStreamVX(c.buf[:], c.buf[:], &c.key, &c.nonce, &c.counter)
c.len = bufSize - copy(dst[i:], c.buf[:len(src)%bufSize])
}
}
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