These patches make threading optional in LLVM. The configuration scripts are now
modified to accept a --disable-threads switch. If this is used, the Mutex class
will be implemented with all functions as no-op. Furthermore, linking against
libpthread will not be done. Finally, the ParallelJIT example needs libpthread
so its makefile was changed to always add -lpthread to the link line.
llvm-svn: 23003
Add an example program that utilizes multiple threads in the JIT to process
work. This was used by Evan Jones as the original test case for ensuring
that the ExecutionEngine was thread safe.
Original source by Evan Jones (adapted from other LLVM JIT examples) and
made LLVM style compliant by Reid Spencer.
llvm-svn: 22411
