[TSan] Optimize handling of racy address

Authored by protze.joachim on Jul 15 2020, 7:45 AM.


[TSan] Optimize handling of racy address

This patch splits the handling of racy address and racy stack into separate
functions. If a race was already reported for the address, we can avoid the
cost for collecting the involved stacks.

This patch also removes the race condition in storing the racy address / racy
stack. This race condition allowed all threads to report the race.

This patch changes the transitive suppression of reports. Previously
suppression could transitively chain memory location and racy stacks.
Now racy memory and racy stack are separate suppressions.

Reviewed by: dvyukov

Differential Revision: https://reviews.llvm.org/D83625