Even sleep(1) lead to episodical flakes on some machines.
Use an invisible by tsan barrier to enforce required execution order instead.
This makes the tests deterministic and faster.
llvm-svn: 226659
Add a script that is used to deflake inherently flaky tsan tests.
It is invoked from lit tests as:
%deflake %run %t
The script runs the target program up to 10 times,
until it produces a tsan warning.
llvm-svn: 209898
Kuba Brecka