[PATCH] D11072: Implement tool to convert bitcode to text.

[Karl Schimpf via llvm-commits]

kschimpf added a comment.

Met with Chandler Carruth, JF Bastien , Kostya Serebryany, and myself (Karl Schimpf) to discuss how to proceed with helping the LLVM community using fuzzing. Briefly discussed patch http://reviews.llvm.org/D11072. Then discussed the overall goals of the LLVM community with respect to fuzzing.

We discussed that there really should be 3 levels of fuzzing:

1. Parsing .ll files to generate IR.
2. Optimization phases of the compiler
3. Using bitcode to represent other structured objects.

It was also noted that once these levels are more stable, one could move into more structural fuzzing (details omitted here).

As such, patch http://reviews.llvm.org/D11072 doesn’t really fit this strategy. Hence, this patch will be abandoned.

However, I will continue to work towards fuzzing LLVM to improve the code quality. My initial goals will be to apply afl-fuzz to a corpus of .ll files to find errors in parsing .ll files (i.e. run llvm-as).

I will also work with Kostya on building a fuzzer using libFuzzer to also test parsing .ll files to generate IR. To improve code coverage, the goal is to call functions that remove the bitcode writing step of llvm-as.

Once llvm-as is relatively stable, focus will then move forward to the optimization phases of the compiler.

Any help or comments from the general LLVM community to help with fuzzing is greatly appreciated.


http://reviews.llvm.org/D11072