There is a hard-to-reproduce crash happening on OS X that involves terminating the main thread (dispatch_main does that, see discussion at http://reviews.llvm.org/D18496) and later reusing the main thread's ThreadContext. This patch disables reuse of the main thread. I believe this problem exists only on OS X, because on other systems the main thread cannot be terminated without exiting the process.
Differential Revision: http://reviews.llvm.org/D19722
llvm-svn: 268238
Vector clocks is the most actively allocated object in tsan runtime.
Current internal allocator is not scalable enough to handle allocation
of clocks in scalable way (too small caches). This changes transforms
clocks to 2-level array with 512-byte blocks. Since all blocks are of
the same size, it's possible to cache them more efficiently in per-thread caches.
llvm-svn: 214912