memcmp: no-simd no case loop can scan forward

src/util-memcmp.h

@@ -41,13 +41,8 @@ void MemcmpRegisterTests(void);
 static inline int
 MemcmpLowercase(const void *s1, const void *s2, size_t n)
 {
-    ssize_t i;
-
-    /* check backwards because we already tested the first
-     * 2 to 4 chars. This way we are more likely to detect
-     * a miss and thus speed up a little... */
-    for (i = n - 1; i >= 0; i--) {
-        if (((uint8_t *)s1)[i] != u8_tolower(*(((uint8_t *)s2)+i)))
+    for (size_t i = 0; i < n; i++) {
+        if (((uint8_t *)s1)[i] != u8_tolower(((uint8_t *)s2)[i]))
             return 1;
     }