Thin-cell decoder changes.

Add hard decoder gates (nand, inv, pnan)
Add conditions for routing using LI layer in s8.
Generalize bus layers for decoders.
Move custom cells to own directory.
Fixed via directions, etc.
Add 4x16 hierarchical decoder and test case

compiler/tests/08_wordline_driver_array_test.py

@@ -0,0 +1,37 @@
+#!/usr/bin/env python3
+# See LICENSE for licensing information.
+#
+# Copyright (c) 2016-2019 Regents of the University of California and The Board
+# of Regents for the Oklahoma Agricultural and Mechanical College
+# (acting for and on behalf of Oklahoma State University)
+# All rights reserved.
+#
+import unittest
+from testutils import *
+import sys,os
+sys.path.append(os.getenv("OPENRAM_HOME"))
+import globals
+from globals import OPTS
+from sram_factory import factory
+import debug
+
+
+class wordline_driver_array_test(openram_test):
+
+    def runTest(self):
+        config_file = "{}/tests/configs/config".format(os.getenv("OPENRAM_HOME"))
+        globals.init_openram(config_file)
+
+        # check wordline driver for single port
+        debug.info(2, "Checking driver")
+        tx = factory.create(module_type="wordline_driver_array", rows=8, cols=32)
+        self.local_check(tx)
+
+        globals.end_openram()
+
+# run the test from the command line
+if __name__ == "__main__":
+    (OPTS, args) = globals.parse_args()
+    del sys.argv[1:]
+    header(__file__, OPTS.tech_name)
+    unittest.main(testRunner=debugTestRunner())