Merge pull request #3332 from jeffng-or/cts-buf-distance-tunable

Make CTS_BUF_DISTANCE tunable

Author: maliberty

flow/scripts/variables.yaml

@@ -769,11 +769,15 @@ CTS_BUF_DISTANCE:
     Distance (in microns) between buffers.
   stages:
     - cts
+  tunable: 1
+  type: float
 CTS_BUF_LIST:
   description: |
     List of cells used to construct the clock tree. Overrides buffer inference.
   stages:
     - cts
+  tunable: 1
+  type: float
 CTS_CLUSTER_DIAMETER:
   description: >
     Maximum diameter (in microns) of sink cluster.