sse42.go

package sse42

//#include <string.h>
//#cgo linux CFLAGS: -O3 -msse4.2
import "C"
import "unsafe"

func Equal(b1, b2 []byte) bool {
	if len(b1) != len(b2) {
		return false
	}
	if len(b1) == 0 {
		return true
	}
	return C.strncmp((*C.char)(unsafe.Pointer(&b1[0])), (*C.char)(unsafe.Pointer(&b2[0])), C.size_t(len(b1))) == 0
}

sse42_test.go

package sse42

import (
	"bytes"
	"testing"
)

const size = 1 << 20

func BenchmarkEqual(b *testing.B) {
	b1 := make([]byte, size)
	b2 := make([]byte, size)
	// this should make it panic?!
	b1[1] = 1
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		if !Equal(b1, b2) {
			panic("failed")
		}
	}
}

func BenchmarkBytesEqual(b *testing.B) {
	b1 := make([]byte, size)
	b2 := make([]byte, size)
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		if !bytes.Equal(b1, b2) {
			panic("failed")
		}
	}
}

func BenchmarkStringEqual(b *testing.B) {
	s1 := string(make([]byte, size))
	s2 := string(make([]byte, size))
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		if s1 != s2 {
			panic("failed")
		}
	}
}