no functional change, avoid conditional jump
MODIFY
gcc_plugin/afl-gcc-rt.o.c
gcc_plugin/afl-gcc-rt.o.c
@@ -58,11 +58,14 @@ __thread u32 __afl_prev_loc;
void __afl_trace(u32 x) {
u32 l = __afl_prev_loc;
- __afl_area_ptr[l ^ x]++;
- /* // neverZero is disable as gcc creates non-performant code. shame on you gcc
- if (__afl_area_ptr[l ^ x] == 0)
- __afl_area_ptr[l ^ x]++;
- */
+
+#if 0 /* enable for neverZero feature. By default disabled since too inefficient :-( */
+ /* @Marc: avoid conditional jumps here */
+ __afl_area_ptr[l ^ x] += 1 + (__afl_area_ptr[l ^ x] == (u8)~0);
+#else
+ ++__afl_area_ptr[l ^ x];
+#endif
+
__afl_prev_loc = (x >> 1);
return;

no functional change, avoid conditional jump