Thanks to Clemens (hammacher@cs.uni-saarland.de) extension of the
arcanist unit test engine, we can run the llvm-lit tests automatically.
Similar to the linters, aracanist will run all tests for each uploaded
commit and asks the commiter for a statements in case unit tests fail.
To use this feature the unit test engine needs to find the polly build
directory. Currently we support the following setups:
$POLLY_BUILD_DIR (environment variable)
<root>/build
<root>.build
<root>-build
<root:s/src/build>
<cwd>
llvm-svn: 217396
Johannes Doerfert