added SKIP_CRIT_VT_SWAP

Signed-off-by: Cho Moon <[email protected]>

Author: precisionmoon

flow/scripts/util.tcl

@@ -26,6 +26,7 @@ proc repair_timing_helper { args } {
   append_env_var additional_args SKIP_BUFFER_REMOVAL -skip_buffer_removal 0
   append_env_var additional_args SKIP_LAST_GASP -skip_last_gasp 0
   append_env_var additional_args SKIP_VT_SWAP -skip_vt_swap 0
+  append_env_var additional_args SKIP_CRIT_VT_SWAP -skip_crit_vt_swap 0
   append_env_var additional_args MATCH_CELL_FOOTPRINT -match_cell_footprint 0
   log_cmd repair_timing {*}$additional_args
 }

flow/scripts/variables.yaml

@@ -577,6 +577,15 @@ SKIP_VT_SWAP:
     - cts
     - floorplan
     - grt
+SKIP_CRIT_VT_SWAP:
+  description: >
+    Do not perform VT swap on critical cells to improve QoR (default: do critical VT swap).
+    This is an additional VT swap on critical cells that remain near the end of setup fixing.
+    If SKIP_VT_SWAP is set to 1, this also disables critical cell VT swap.
+  stages:
+    - cts
+    - floorplan
+    - grt
 REMOVE_CELLS_FOR_EQY:
   description: >
     String patterns directly passed to write_verilog -remove_cells <> for