//go:build (amd64 || arm64) && !appengine && gc && !purego
// +build amd64 arm64
// +build !appengine
// +build gc
// +build !purego
package xxhash
// Sum64 computes the 64-bit xxHash digest of b with a zero seed.
//
//go:noescape
func Sum64(b []byte) uint64
func writeBlocks(d *Digest, b []byte) int