[all-commits] [llvm/llvm-project] a30dbb: Redistribute energy for Corpus

[taotao gu via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: a30dbbe9241fa72580638eb08468d3e6a39cf2b0
      https://github.com/llvm/llvm-project/commit/a30dbbe9241fa72580638eb08468d3e6a39cf2b0
  Author: gtt1995 <1271159369 at qq.com>
  Date:   2021-09-08 (Wed, 08 Sep 2021)

  Changed paths:
    M compiler-rt/lib/fuzzer/FuzzerDriver.cpp
    M compiler-rt/lib/fuzzer/FuzzerFlags.def
    M compiler-rt/lib/fuzzer/FuzzerFork.cpp
    M compiler-rt/lib/fuzzer/FuzzerOptions.h
    A compiler-rt/test/fuzzer/fork_corpus_groups.test

  Log Message:
  -----------
  Redistribute energy for Corpus

I found that the initial corpus allocation of fork mode has certain defects.
I designed a new initial corpus allocation strategy based on size grouping.
This method can give more energy to the small seeds in the corpus and
increase the throughput of the test.

Fuzzbench data (glibfuzzer is -fork_corpus_groups=1):
https://www.fuzzbench.com/reports/experimental/2021-08-05-parallel/index.html

Reviewed By: morehouse

Differential Revision: https://reviews.llvm.org/D105084