support for 1.9 bit counts

popcnt_19.go

@@ -0,0 +1,45 @@
+// +build go1.9
+
+package bitset
+
+import "math/bits"
+
+func popcntSlice(s []uint64) uint64 {
+	var cnt int
+	for _, x := range s {
+		cnt += bits.OnesCount64(x)
+	}
+	return uint64(cnt)
+}
+
+func popcntMaskSlice(s, m []uint64) uint64 {
+	var cnt int
+	for i := range s {
+		cnt += bits.OnesCount64(s[i] &^ m[i])
+	}
+	return uint64(cnt)
+}
+
+func popcntAndSlice(s, m []uint64) uint64 {
+	var cnt int
+	for i := range s {
+		cnt += bits.OnesCount64(s[i] & m[i])
+	}
+	return uint64(cnt)
+}
+
+func popcntOrSlice(s, m []uint64) uint64 {
+	var cnt int
+	for i := range s {
+		cnt += bits.OnesCount64(s[i] | m[i])
+	}
+	return uint64(cnt)
+}
+
+func popcntXorSlice(s, m []uint64) uint64 {
+	var cnt int
+	for i := range s {
+		cnt += bits.OnesCount64(s[i] ^ m[i])
+	}
+	return uint64(cnt)
+}