getLLVMCMakeBuildFactory constructs the -jN option incorrectly when running "make check-all".
Example:
http://lab.llvm.org:8011/builders/llvm-hexagon-elf/builds/26076/steps/test-llvm/logs/stdio
make check-all VERBOSE=1 'LIT_ARGS=-v -j 16' in dir /var/lib/buildbot/slaves/hexagon-build-03/llvm-hexagon-elf/llvm.obj (timeout 1200 secs) watching logfiles {} argv: ['make', 'check-all', 'VERBOSE=1', 'LIT_ARGS=-v -j 16']
Specifically, the -jN option is a part of LIT_ARGS, not the make invocation.