libldi library to collect extended backtrace information; switch
to the libBacktraceRecording library and its APIs. Complete the
work of adding QueueItems to Queues and allow for the QueueItems
to be interrogated about their extended backtraces in turn.
There's still cleanup and documentation to do on this code but the
code is functional and I it's a good time to get the work-in-progress
checked in.
<rdar://problem/15314027>
llvm-svn: 200822
libdispatch aka Grand Central Dispatch (GCD) queues. Still fleshing out the
documentation and testing of these but the overall API is settling down so it's
a good time to check it in.
<rdar://problem/15600370>
llvm-svn: 197190
Jason Molenda