diff --git a/vendor/github.com/cespare/xxhash/rotate19.go b/vendor/github.com/cespare/xxhash/rotate19.go
new file mode 100644
index 0000000..b99612b
--- /dev/null
+++ b/vendor/github.com/cespare/xxhash/rotate19.go
@@ -0,0 +1,14 @@
+// +build go1.9
+
+package xxhash
+
+import "math/bits"
+
+func rol1(x uint64) uint64  { return bits.RotateLeft64(x, 1) }
+func rol7(x uint64) uint64  { return bits.RotateLeft64(x, 7) }
+func rol11(x uint64) uint64 { return bits.RotateLeft64(x, 11) }
+func rol12(x uint64) uint64 { return bits.RotateLeft64(x, 12) }
+func rol18(x uint64) uint64 { return bits.RotateLeft64(x, 18) }
+func rol23(x uint64) uint64 { return bits.RotateLeft64(x, 23) }
+func rol27(x uint64) uint64 { return bits.RotateLeft64(x, 27) }
+func rol31(x uint64) uint64 { return bits.RotateLeft64(x, 31) }