Initial QSfera import

Server/vendor/github.com/bits-and-blooms/bitset/popcnt.go

@@ -0,0 +1,59 @@
+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
+	// this explicit check eliminates a bounds check in the loop
+	if len(m) < len(s) {
+		panic("mask slice is too short")
+	}
+	for i := range s {
+		cnt += bits.OnesCount64(s[i] &^ m[i])
+	}
+	return uint64(cnt)
+}
+
+func popcntAndSlice(s, m []uint64) uint64 {
+	var cnt int
+	// this explicit check eliminates a bounds check in the loop
+	if len(m) < len(s) {
+		panic("mask slice is too short")
+	}
+	for i := range s {
+		cnt += bits.OnesCount64(s[i] & m[i])
+	}
+	return uint64(cnt)
+}
+
+func popcntOrSlice(s, m []uint64) uint64 {
+	var cnt int
+	// this explicit check eliminates a bounds check in the loop
+	if len(m) < len(s) {
+		panic("mask slice is too short")
+	}
+	for i := range s {
+		cnt += bits.OnesCount64(s[i] | m[i])
+	}
+	return uint64(cnt)
+}
+
+func popcntXorSlice(s, m []uint64) uint64 {
+	var cnt int
+	// this explicit check eliminates a bounds check in the loop
+	if len(m) < len(s) {
+		panic("mask slice is too short")
+	}
+	for i := range s {
+		cnt += bits.OnesCount64(s[i] ^ m[i])
+	}
+	return uint64(cnt)
+}