update

mathx/int.go

@@ -3,18 +3,32 @@ package mathx
 import (
 	"github.com/charlienet/go-mixed/expr"
 	"golang.org/x/exp/constraints"
+	"unsafe"
 )
 
-// MaxInt returns the larger one of v1 and v2.
+// Max returns the larger one of v1 and v2.
 func Max[T constraints.Ordered](v1, v2 T) T {
 	return expr.Ternary(v1 > v2, v1, v2)
 }
 
-// MinInt returns the smaller one of v1 and v2.
+// Min returns the smaller one of v1 and v2.
 func Min[T constraints.Ordered](v1, v2 T) T {
 	return expr.Ternary(v1 < v2, v1, v2)
 }
 
+func Abs1[T constraints.Signed](n T) T {
+	shift := 63
+	switch unsafe.Sizeof(n) {
+	case 1:
+		shift = 7
+	case 4:
+		shift = 31
+	}
+
+	y := n >> shift
+	return T((n ^ y) - y)
+}
+
 func Abs(n int64) int64 {
 	y := n >> 63
 	return (n ^ y) - y