Add arm64 to GOARCH switches

Author: ottenhoff

find_match_length.go

@@ -17,7 +17,7 @@ func findMatchLengthWithLimit(s1 []byte, s2 []byte, limit uint) uint {
 	var matched uint = 0
 	_, _ = s1[limit-1], s2[limit-1] // bounds check
 	switch runtime.GOARCH {
-	case "amd64":
+	case "amd64", "arm64":
 		// Compare 8 bytes at at time.
 		for matched+8 <= limit {
 			w1 := binary.LittleEndian.Uint64(s1[matched:])

matchfinder/m4.go

@@ -261,7 +261,7 @@ const hashMul64 = 0x1E35A7BD1E35A7BD
 //	0 <= i && i < j && j <= len(src)
 func extendMatch(src []byte, i, j int) int {
 	switch runtime.GOARCH {
-	case "amd64":
+	case "amd64", "arm64":
 		// As long as we are 8 or more bytes before the end of src, we can load and
 		// compare 8 bytes at a time. If those 8 bytes are equal, repeat.
 		for j+8 < len(src) {