Only unblock source/target instead of all components for cleaner routes

compiler/router/grid.py

@@ -90,6 +90,7 @@ class grid:
         else:
             self.add_map(n)
             self.map[n].source=True
+            self.map[n].blocked=False
             self.source.add(n)
 
     def clear_target(self):
@@ -104,8 +105,9 @@ class grid:
         else:
             self.add_map(n)
             self.map[n].target=True
+            self.map[n].blocked=False
             self.target.add(n)
-
+            
     def add_source(self, track_list):
         debug.info(3, "Adding source list={0}".format(str(track_list)))
         for n in track_list:

compiler/router/router.py

@@ -355,7 +355,7 @@ class router(router_tech):
         # Start fresh. Not the best for run-time, but simpler.
         self.clear_blockages()
         # This adds the initial blockges of the design
-        #print("BLOCKING:", self.blocked_grids)
+        # print("BLOCKING:", self.blocked_grids)
         self.set_blockages(self.blocked_grids, True)
 
         # Block all of the supply rails
@@ -382,8 +382,9 @@ class router(router_tech):
         # Don't mark the other components as targets since we want to route
         # directly to a rail, but unblock all the source components so we can
         # route over them
-        blockage_grids = {y for x in self.pin_groups[pin_name] for y in x.grids}
-        self.set_blockages(blockage_grids, False)
+        # 1/6/21: This would cause things that looked like loops in the supply tree router
+        # blockage_grids = {y for x in self.pin_groups[pin_name] for y in x.grids}
+        # self.set_blockages(blockage_grids, False)
 
     def convert_shape_to_units(self, shape):
         """

compiler/router/supply_tree_router.py

@@ -144,15 +144,13 @@ class supply_tree_router(router):
 
             # Marks all pin components except index as target
             self.add_pin_component_target(pin_name, dest_idx)
-            
+
             # Actually run the A* router
             if self.run_router(detour_scale=detour_scale):
                 return
 
         self.write_debug_gds("debug_route.gds", True)
 
-
-
     def add_io_pin(self, instance, pin_name, new_name=""):
         """
         Add a signle input or output pin up to metal 3.