Do not try to find PSI element, but always use the IR element offsets
instead. This greatly simplifies test data because we don't need to have
custom PSI- and LT- based diagnostic ranges in every test, and K1/K2
behavior also is mostly the same.
The exact offset ranges are not as important for backend diagnostics, so
it's better to have K2+PSI and K2+LT behaving the same.
Alexander Udalov
965946d3ef