rm bitutil xorbytes helper func

This commit is contained in:
Sahil-4555 2025-12-23 10:38:26 +05:30
parent 4eb5b66d9e
commit 121c43075e
2 changed files with 0 additions and 79 deletions

View file

@ -8,7 +8,6 @@
package bitutil
import (
"crypto/subtle"
"runtime"
"unsafe"
)
@ -16,19 +15,6 @@ import (
const wordSize = int(unsafe.Sizeof(uintptr(0)))
const supportsUnaligned = runtime.GOARCH == "386" || runtime.GOARCH == "amd64" || runtime.GOARCH == "ppc64" || runtime.GOARCH == "ppc64le" || runtime.GOARCH == "s390x"
// XORBytes xors the bytes in a and b. The destination is assumed to have enough
// space. Returns the number of bytes xor'd.
//
// If dst does not have length at least n,
// XORBytes panics without writing anything to dst.
//
// dst and x or y may overlap exactly or not at all,
// otherwise XORBytes may panic.
//
// Deprecated: use crypto/subtle.XORBytes
func XORBytes(dst, a, b []byte) int {
return subtle.XORBytes(dst, a, b)
}
// ANDBytes ands the bytes in a and b. The destination is assumed to have enough
// space. Returns the number of bytes and'd.

View file

@ -11,45 +11,6 @@ import (
"testing"
)
// Tests that bitwise XOR works for various alignments.
func TestXOR(t *testing.T) {
for alignP := 0; alignP < 2; alignP++ {
for alignQ := 0; alignQ < 2; alignQ++ {
for alignD := 0; alignD < 2; alignD++ {
p := make([]byte, 1023)[alignP:]
q := make([]byte, 1023)[alignQ:]
for i := 0; i < len(p); i++ {
p[i] = byte(i)
}
for i := 0; i < len(q); i++ {
q[i] = byte(len(q) - i)
}
d1 := make([]byte, 1023+alignD)[alignD:]
d2 := make([]byte, 1023+alignD)[alignD:]
XORBytes(d1, p, q)
naiveXOR(d2, p, q)
if !bytes.Equal(d1, d2) {
t.Error("not equal", d1, d2)
}
}
}
}
}
// naiveXOR xors bytes one by one.
func naiveXOR(dst, a, b []byte) int {
n := len(a)
if len(b) < n {
n = len(b)
}
for i := 0; i < n; i++ {
dst[i] = a[i] ^ b[i]
}
return n
}
// Tests that bitwise AND works for various alignments.
func TestAND(t *testing.T) {
for alignP := 0; alignP < 2; alignP++ {
@ -124,32 +85,6 @@ func TestTest(t *testing.T) {
}
}
// Benchmarks the potentially optimized XOR performance.
func BenchmarkFastXOR1KB(b *testing.B) { benchmarkFastXOR(b, 1024) }
func BenchmarkFastXOR2KB(b *testing.B) { benchmarkFastXOR(b, 2048) }
func BenchmarkFastXOR4KB(b *testing.B) { benchmarkFastXOR(b, 4096) }
func benchmarkFastXOR(b *testing.B, size int) {
p, q := make([]byte, size), make([]byte, size)
for i := 0; i < b.N; i++ {
XORBytes(p, p, q)
}
}
// Benchmarks the baseline XOR performance.
func BenchmarkBaseXOR1KB(b *testing.B) { benchmarkBaseXOR(b, 1024) }
func BenchmarkBaseXOR2KB(b *testing.B) { benchmarkBaseXOR(b, 2048) }
func BenchmarkBaseXOR4KB(b *testing.B) { benchmarkBaseXOR(b, 4096) }
func benchmarkBaseXOR(b *testing.B, size int) {
p, q := make([]byte, size), make([]byte, size)
for i := 0; i < b.N; i++ {
naiveXOR(p, p, q)
}
}
// Benchmarks the potentially optimized AND performance.
func BenchmarkFastAND1KB(b *testing.B) { benchmarkFastAND(b, 1024) }
func BenchmarkFastAND2KB(b *testing.B) { benchmarkFastAND(b, 2048) }