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// Copyright 2013 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.
package xor
import (
"bytes"
"crypto/rand"
"fmt"
"io"
"testing"
)
func TestXOR(t *testing.T) {
for j := 1; j <= 1024; j++ {
if testing.Short() && j > 16 {
break
}
for alignP := 0; alignP < 2; alignP++ {
for alignQ := 0; alignQ < 2; alignQ++ {
for alignD := 0; alignD < 2; alignD++ {
p := make([]byte, j)[alignP:]
q := make([]byte, j)[alignQ:]
d0 := make([]byte, j+alignD+1)
d0[j+alignD] = 42
d1 := d0[alignD : j+alignD]
d2 := make([]byte, j+alignD)[alignD:]
if _, err := io.ReadFull(rand.Reader, p); err != nil {
t.Fatal(err)
}
if _, err := io.ReadFull(rand.Reader, q); err != nil {
t.Fatal(err)
}
XorBytes(d1, p, q)
n := min(p, q)
for i := 0; i < n; i++ {
d2[i] = p[i] ^ q[i]
}
if !bytes.Equal(d1, d2) {
t.Errorf(
"p: %#v, q: %#v, "+
"expect: %#v, "+
"result: %#v",
p, q, d2, d1,
)
}
if d0[j+alignD] != 42 {
t.Error("guard overwritten")
}
}
}
}
}
}
func min(a, b []byte) int {
n := len(a)
if len(b) < n {
n = len(b)
}
return n
}
func BenchmarkXORAligned(b *testing.B) {
dst := make([]byte, 1<<15)
data0 := make([]byte, 1<<15)
data1 := make([]byte, 1<<15)
sizes := []int64{1 << 3, 1 << 7, 1 << 11, 1 << 15}
for _, size := range sizes {
b.Run(fmt.Sprintf("%dBytes", size), func(b *testing.B) {
s0 := data0[:size]
s1 := data1[:size]
b.SetBytes(size)
for i := 0; i < b.N; i++ {
XorBytes(dst, s0, s1)
}
})
}
}
func BenchmarkXORUnalignedDst(b *testing.B) {
dst := make([]byte, 1<<15+1)
data0 := make([]byte, 1<<15)
data1 := make([]byte, 1<<15)
sizes := []int64{1 << 3, 1 << 7, 1 << 11, 1 << 15}
for _, size := range sizes {
b.Run(fmt.Sprintf("%dBytes", size), func(b *testing.B) {
s0 := data0[:size]
s1 := data1[:size]
b.SetBytes(size)
for i := 0; i < b.N; i++ {
XorBytes(dst[1:], s0, s1)
}
})
}
}
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