diff --git a/vendor/github.com/cespare/xxhash/xxhash_amd64.go b/vendor/github.com/cespare/xxhash/xxhash_amd64.go
new file mode 100644
index 0000000..d617652
--- /dev/null
+++ b/vendor/github.com/cespare/xxhash/xxhash_amd64.go
@@ -0,0 +1,12 @@
+// +build !appengine
+// +build gc
+// +build !purego
+
+package xxhash
+
+// Sum64 computes the 64-bit xxHash digest of b.
+//
+//go:noescape
+func Sum64(b []byte) uint64
+
+func writeBlocks(x *xxh, b []byte) []byte