Summary:
Fix read/write in binary format, which crashes Python 3.
Additionally, clean up redundant (as for Python 3) code and
fix a handful of flake8 warnings.
Differential Revision: https://reviews.llvm.org/D79932
Contrary to the deleted comment, in most cases CmpRuns.py produces a
fairly small amount of output, which is useful to see straight away to
see what has changed when executing the integration tests.
llvm-svn: 316618
Valeriy Savchenko