[PATCH] D49578: [libFuzzer] Handle unstable edges by poisoning unstable edges

[Kyungtak Woo via Phabricator via llvm-commits]

kevinwkt marked an inline comment as done.
kevinwkt added a comment.

In https://reviews.llvm.org/D49578#1176909, @morehouse wrote:

> So this is basically the `ZeroUnstable` mode with one less pass over the counters?


"ZeroUnstable" puts 0 in unstable edges and pretends it was never hit.
"PoisonUnstable" takes into account new unstable edges only if a new stable edge is also found. 
This comes from the assumption that unstable edges should be given weight as long as a new deterministic edge is found to reward that input.
We only take into account new unstable edges (and not any unstable edge hit), since we believe that this "reward" for reaching that edge has been given to other inputs.

Hope this makes it a bit clearer.


https://reviews.llvm.org/D49578