[libFuzzer] experimental feature -reduce_inputs (off by default) that tries to replace elements in the corpus with smaller ones that have the same feature set. Still needs tuning

git-svn-id: svn://svn.chromium.org/llvm-project/llvm/trunk/lib/Fuzzer@307873 0b72dbe1-c17f-4bc7-b9db-2b4152be0356
9 files changed