Create an out-directory per sanitizer

[alex]

This makes it easier to work on multiple things concurrently (most notably running a fuzzer and profiling/coverage)

[alex]

I tested a handful of commands by hand, but there's no automated tests so there exists the possibility of a regression

[inferno-chromium]

I think we need engine as well.

/out/libpng/libfuzzer-msan
/out/libpng/afl-asan

[alex]

Good point

[inferno-chromium]

ah! there is atleast one isssue, we would need to repeat --sanitizer and --engine in run_* commands in documentation. Will let @oliverchang evaluate this pull request if this makes sense or keeping just /out is better.

[alex]

Yes, you need to pass the --sanitizer (and --engine) to anything that runs the binary, not just the build.

[oliverchang]

I think helper.py needs a refactor in general -- it has grown a lot than initially envisioned.

I'm thinking a more general fix to this would be to support custom working directorys. e.g. something that looks like this (inspired by chromium's GN):

# generates some metadata files and a symlink to helper.py
$ python infra/helper.py create_config --sanitizer=blah --engine=blah /path/to/build/dir

# /path/to/build/dir remembers the sanitizer and engine config. calling helper.py frmo
# that directory automatically sets them.
$ cd /path/to/build/dir
$ python helper.py build_image # and all other commands etc
$ python helper.py build_fuzzers # stores builds in /path/to/build/dir

[Dor1s]

This didn't have any updates in a year, closing.