LLVM lnt - Test Backend Pass


I would like to ask whether it is possible to test my own backend pass with
LNT tool and LLVM Test Suite.

I successfully installed LNT and downloaded LLVM Test Suite. Now I am able
to run the tool with commant line option similar to this: lnt runtest nt
--sandbox SANDBOX --cc ~/{path_to_clang}/clang --test-suite
~/{path_to_test_suite}/llvm-test-suite , but i have two main problems:

1) each run finishes with :
2013-02-11 10:19:34: configuring...
2013-02-11 10:19:38: building test-suite tools
2013-02-11 10:19:39: executing "nightly tests" with -j1...
2013-02-11 10:36:57: executing test modules
2013-02-11 10:36:57: loading nightly test data...
nt.py:810: fatal error: nightly test failed, no report generated

2) I am not able to run my own backend pass. Is there any command line
option to include that pass to the test run ? I found some articles about
modifying Makefile-s, but LLVM Testing Infrastructure Guide recommends to
use LNT tool. (Until now I have tested my pass only manualy, each time using
OPT tool to load the pass.)

If LNT is not the right tool to test backend pass, could you recommend me
any other way to test it ?

I would really appreciate some advice or ( better :slight_smile: ) expample of usage.