little has_new_bits improvement
MODIFY
src/afl-fuzz-bitmap.c
src/afl-fuzz-bitmap.c
@@ -88,7 +88,8 @@ u8 has_new_bits(afl_state_t *afl, u8 *virgin_map) {
u32 i = (afl->fsrv.map_size >> 2);
#endif /* ^WORD_SIZE_64 */
- if (i == 0) i = 1;
+ // the map size must be a minimum of 8 bytes.
+ // for variable/dynamic map sizes this is ensured in the forkserver
u8 ret = 0;
@@ -98,6 +99,7 @@ u8 has_new_bits(afl_state_t *afl, u8 *virgin_map) {
that have not been already cleared from the virgin map - since this will
almost always be the case. */
+ // the (*current) is unnecessary but speeds up the overall comparison
if (unlikely(*current) && unlikely(*current & *virgin)) {
if (likely(ret < 2)) {
@@ -110,7 +112,7 @@ u8 has_new_bits(afl_state_t *afl, u8 *virgin_map) {
#ifdef WORD_SIZE_64
- if ((cur[0] && vir[0] == 0xff) || (cur[1] && vir[1] == 0xff) ||
+ if (*virgin == 0xffffffffffffffff || (cur[0] && vir[0] == 0xff) || (cur[1] && vir[1] == 0xff) ||
(cur[2] && vir[2] == 0xff) || (cur[3] && vir[3] == 0xff) ||
(cur[4] && vir[4] == 0xff) || (cur[5] && vir[5] == 0xff) ||
(cur[6] && vir[6] == 0xff) || (cur[7] && vir[7] == 0xff))
@@ -120,7 +122,7 @@ u8 has_new_bits(afl_state_t *afl, u8 *virgin_map) {
#else
- if ((cur[0] && vir[0] == 0xff) || (cur[1] && vir[1] == 0xff) ||
+ if (*virgin == 0xffffffff || (cur[0] && vir[0] == 0xff) || (cur[1] && vir[1] == 0xff) ||
(cur[2] && vir[2] == 0xff) || (cur[3] && vir[3] == 0xff))
ret = 2;
else
@@ -139,7 +141,7 @@ u8 has_new_bits(afl_state_t *afl, u8 *virgin_map) {
}
- if (unlikely(ret) && unlikely(virgin_map == afl->virgin_bits))
+ if (unlikely(ret) && likely(virgin_map == afl->virgin_bits))
afl->bitmap_changed = 1;
return ret;

little has_new_bits improvement