github.com/anthdm/go-ethereum@v1.8.4-0.20180412101906-60516c83b011/crypto/sha3/xor_unaligned.go (about)

     1  // Copyright 2015 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // +build amd64 386 ppc64le
     6  // +build !appengine
     7  
     8  package sha3
     9  
    10  import "unsafe"
    11  
    12  func xorInUnaligned(d *state, buf []byte) {
    13  	bw := (*[maxRate / 8]uint64)(unsafe.Pointer(&buf[0]))
    14  	n := len(buf)
    15  	if n >= 72 {
    16  		d.a[0] ^= bw[0]
    17  		d.a[1] ^= bw[1]
    18  		d.a[2] ^= bw[2]
    19  		d.a[3] ^= bw[3]
    20  		d.a[4] ^= bw[4]
    21  		d.a[5] ^= bw[5]
    22  		d.a[6] ^= bw[6]
    23  		d.a[7] ^= bw[7]
    24  		d.a[8] ^= bw[8]
    25  	}
    26  	if n >= 104 {
    27  		d.a[9] ^= bw[9]
    28  		d.a[10] ^= bw[10]
    29  		d.a[11] ^= bw[11]
    30  		d.a[12] ^= bw[12]
    31  	}
    32  	if n >= 136 {
    33  		d.a[13] ^= bw[13]
    34  		d.a[14] ^= bw[14]
    35  		d.a[15] ^= bw[15]
    36  		d.a[16] ^= bw[16]
    37  	}
    38  	if n >= 144 {
    39  		d.a[17] ^= bw[17]
    40  	}
    41  	if n >= 168 {
    42  		d.a[18] ^= bw[18]
    43  		d.a[19] ^= bw[19]
    44  		d.a[20] ^= bw[20]
    45  	}
    46  }
    47  
    48  func copyOutUnaligned(d *state, buf []byte) {
    49  	ab := (*[maxRate]uint8)(unsafe.Pointer(&d.a[0]))
    50  	copy(buf, ab[:])
    51  }
    52  
    53  var (
    54  	xorIn   = xorInUnaligned
    55  	copyOut = copyOutUnaligned
    56  )
    57  
    58  const xorImplementationUnaligned = "unaligned"