The test unconditionally assumes a particular cpu has a backend build in the target.

Buildbots for some hosts may choose to build only their own backend in order to
maximise testing-turnaround time. Move the test into a prefixed directory so
lit's standard "backend specific" suppression can be done.

llvm-svn: 169604

test/Transforms/LoopIdiom/X86/lit.local.cfg

@@ -0,0 +1,6 @@
+config.suffixes = ['.ll', '.c', '.cpp']
+
+targets = set(config.root.targets_to_build.split())
+if not 'X86' in targets:
+    config.unsupported = True
+