Teach 'make check-lit' to run unittests.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81753 91177308-0d34-0410-b5e6-96231b3b80d8

test/Unit/lit.cfg

@@ -0,0 +1,65 @@
+# -*- Python -*-
+
+# Configuration file for the 'lit' test runner.
+
+import os
+
+# name: The name of this test suite.
+config.name = 'LLVM-Unit'
+
+# suffixes: A list of file extensions to treat as test files, this is actually
+# set by on_clone().
+config.suffixes = []
+
+# test_source_root: The root path where tests are located.
+# test_exec_root: The root path where tests should be run.
+llvm_obj_root = getattr(config, 'llvm_obj_root', None)
+if llvm_obj_root is not None:
+    config.test_exec_root = os.path.join(llvm_obj_root, 'unittests')
+    config.test_source_root = config.test_exec_root
+
+# testFormat: The test format to use to interpret tests.
+llvm_build_mode = getattr(config, 'llvm_build_mode', "Debug")
+config.test_format = lit.formats.GoogleTest(llvm_build_mode, 'Tests')
+
+###
+
+import os
+
+# Check that the object root is known.
+if config.test_exec_root is None:
+    # Otherwise, we haven't loaded the site specific configuration (the user is
+    # probably trying to run on a test file directly, and either the site
+    # configuration hasn't been created by the build system, or we are in an
+    # out-of-tree build situation).
+
+    # Try to detect the situation where we are using an out-of-tree build by
+    # looking for 'llvm-config'.
+    #
+    # FIXME: I debated (i.e., wrote and threw away) adding logic to
+    # automagically generate the lit.site.cfg if we are in some kind of fresh
+    # build situation. This means knowing how to invoke the build system
+    # though, and I decided it was too much magic.
+
+    llvm_config = lit.util.which('llvm-config', config.environment['PATH'])
+    if not llvm_config:
+        lit.fatal('No site specific configuration available!')
+
+    # Get the source and object roots.
+    llvm_src_root = lit.util.capture(['llvm-config', '--src-root']).strip()
+    llvm_obj_root = lit.util.capture(['llvm-config', '--obj-root']).strip()
+
+    # Validate that we got a tree which points to here.
+    this_src_root = os.path.join(os.path.dirname(__file__),'..','..')
+    if os.path.realpath(llvm_src_root) != os.path.realpath(this_src_root):
+        lit.fatal('No site specific configuration available!')
+
+    # Check that the site specific configuration exists.
+    site_cfg = os.path.join(llvm_obj_root, 'test', 'Unit', 'lit.site.cfg')
+    if not os.path.exists(site_cfg):
+        lit.fatal('No site specific configuration available!')
+
+    # Okay, that worked. Notify the user of the automagic, and reconfigure.
+    lit.note('using out-of-tree build at %r' % llvm_obj_root)
+    lit.load_config(config, site_cfg)
+    raise SystemExit