The threaded cxa guard test attempted to test multithreaded waiting
by lining up a bunch of threads at a held init lock and releasing them.
The test initially wanted each thread to observe the lock being held,
but some threads may arive too late.
This patch cleans up the test and relaxes the restrictions.
llvm-svn: 359785
This patch does three main things:
(1) It re-writes the cxa guard implementation to make it testable.
(2) Adds support for recursive init detection on non-apple platforms.
(3) It adds a futex based implementation.
The futex based implementation locks and notifies on a per-object basis, unlike the
current implementation which uses a global lock for all objects. Once this patch settles
I'll turn it on by default when supported.
llvm-svn: 359060
Eric Fiselier