I've found it very difficult to get test/parallel/omp_nested.c to pass
consistently across my build environments. The problem is that it creates N^2
threads (it is testing nested parallel regions), and that often exceeds the
thread limits on systems with many cores. We do raise the process limits in
lit, and that often helps, but if running lit with a smaller number of threads
or on a system where we're otherwise resource constrained, this particular test
tends to fail (because the runtime cannot create a sufficient number of
threads).
This seems to work: if the maximum number of threads is more than some small
number, then cap the number of threads used for the parallel region. The choice
of 4 here is somewhat arbitrary.
Differential Revision: https://reviews.llvm.org/D32033
llvm-svn: 306357
This change introduces a check-libomp target which is based upon llvm's lit
test infrastructure. Each test (generated from the University of Houston's
OpenMP testsuite) is compiled and then run. For each test, an exit status of 0
indicates success and non-zero indicates failure. This way, FileCheck is not
needed. I've added a bit of logic to generate symlinks (libiomp5 and libgomp)
in the build tree so that gcc can be tested as well. When building out-of-
tree builds, the user will have to provide llvm-lit either by specifying
-DLIBOMP_LLVM_LIT_EXECUTABLE or having llvm-lit in their PATH.
Differential Revision: http://reviews.llvm.org/D11821
llvm-svn: 248211