if n, err := strconv.Atoi(s[len("__cgodebug_str__"):]); err == nil {
				return n
			}
		}
		return -1
	}
	indexOfDebugStrlen := func(s string) int {
		// Some systems use leading _ to denote non-assembly symbols.
		if strings.HasPrefix(s, "___") {
			s = s[1:]
		}
		if strings.HasPrefix(s, "__cgodebug_strlen__") {

				ToValidUTF8(test.input, replacement)
			}
		})
	}
}

func makeBenchInputHard() []byte {
	tokens := [...]string{
		"<a>", "<p>", "<b>", "<strong>",
		"</a>", "</p>", "</b>", "</strong>",
		"hello", "world",
	}
	x := make([]byte, 0, 1<<20)
	for {
		i := rand.Intn(len(tokens))
		if len(x)+len(tokens[i]) >= 1<<20 {
			break
		}