[PATCH] [sanitizer] Extend sancov.py to show which PCs are missing from coverage.

[Kostya Serebryany]

LGTM, thanks!

Once committed, please also update the docs at http://clang.llvm.org/docs/SanitizerCoverage.html#how-good-is-the-coverage


http://reviews.llvm.org/D9228

EMAIL PREFERENCES
  http://reviews.llvm.org/settings/panel/emailpreferences/