cts.tcl: drop the CTS_SNAPSHOTS debug checkpoint; the script says what CTS does

docs/contrib/EndpointSlackTracking.md

@@ -24,8 +24,8 @@ Every step then writes `$(REPORTS_DIR)/<step>_endpoint_slack.json`, e.g.
 It works in the single-process `flow/scripts/flow.tcl` flow as well. Steps
 that just copy their input (`orfs_copy_db`, e.g. `5_3_fillcell` without fill
 cells) re-time the design if it is loaded, or else copy the previous step's
-snapshot. Intermediate `.odb` files written through `orfs_write_db` (e.g. CTS
-`save_progress`) also get a snapshot; `*-failed` ones don't.
+snapshot. Intermediate `.odb` files written through `orfs_write_db` (e.g. CTS's
+`4_1_error.odb`) also get a snapshot; `*-failed` ones don't.
 
 A placed step is timed with the parasitics OpenROAD has for it: a bare
 `estimate_parasitics` estimates from the global routes when there are any,

docs/user/FlowVariables.md

@@ -130,7 +130,6 @@ configuration file.
 | <a name="CTS_CLUSTER_DIAMETER"></a>CTS_CLUSTER_DIAMETER| Maximum diameter (in microns) of sink cluster.| |
 | <a name="CTS_CLUSTER_SIZE"></a>CTS_CLUSTER_SIZE| Maximum number of sinks per cluster.| |
 | <a name="CTS_LIB_NAME"></a>CTS_LIB_NAME| Name of the Liberty library to use in selecting the clock buffers.| |
-| <a name="CTS_SNAPSHOTS"></a>CTS_SNAPSHOTS| Create ODB/SDC files at different stages of CTS.| 0|
 | <a name="DESIGN_NAME"></a>DESIGN_NAME| The name of the top-level module of the design.| |
 | <a name="DESIGN_NICKNAME"></a>DESIGN_NICKNAME| DESIGN_NICKNAME just changes the directory name that ORFS outputs to be DESIGN_NICKNAME instead of DESIGN_NAME in case DESIGN_NAME is unwieldy or conflicts with a different design.| |
 | <a name="DETAILED_METRICS"></a>DETAILED_METRICS| If set, then calls report_metrics prior to repair operations in the CTS and global route stages| 0|
@@ -542,7 +541,6 @@ configuration file.
 - [CTS_CLUSTER_DIAMETER](#CTS_CLUSTER_DIAMETER)
 - [CTS_CLUSTER_SIZE](#CTS_CLUSTER_SIZE)
 - [CTS_LIB_NAME](#CTS_LIB_NAME)
-- [CTS_SNAPSHOTS](#CTS_SNAPSHOTS)
 - [DETAILED_METRICS](#DETAILED_METRICS)
 - [DETAIL_PLACEMENT_ARGS](#DETAIL_PLACEMENT_ARGS)
 - [HOLD_SLACK_MARGIN](#HOLD_SLACK_MARGIN)

flow/scripts/cts.tcl

@@ -9,11 +9,6 @@ source_step_tcl PRE CTS
 # so cts does not try to buffer the inverted clocks.
 repair_clock_inverters
 
-proc save_progress { stage } {
-  puts "Run 'make gui_$stage.odb' to load progress snapshot"
-  orfs_write_db $::env(RESULTS_DIR)/$stage.odb
-}
-
 # Run CTS
 set cts_args [list \
   -sink_clustering_enable \
@@ -25,7 +20,6 @@ append_env_var cts_args CTS_CLUSTER_DIAMETER -sink_clustering_max_diameter 1
 append_env_var cts_args CTS_BUF_LIST -buf_list 1
 append_env_var cts_args CTS_LIB_NAME -library 1
 
-
 if { [env_var_exists_and_non_empty CTS_ARGS] } {
   set cts_args $::env(CTS_ARGS)
 }
@@ -34,29 +28,25 @@ set_dont_use $::env(DONT_USE_CELLS)
 
 log_cmd clock_tree_synthesis {*}$cts_args
 
-utl::push_metrics_stage "cts__{}__pre_repair_timing"
-log_cmd estimate_parasitics
 if { $::env(DETAILED_METRICS) } {
+  utl::push_metrics_stage "cts__{}__pre_repair_timing"
+  log_cmd estimate_parasitics
   report_metrics 4 "cts pre-repair-timing"
+  utl::pop_metrics_stage
 }
-utl::pop_metrics_stage
 
 set_placement_padding -global \
   -left $::env(CELL_PAD_IN_SITES_DETAIL_PLACEMENT) \
   -right $::env(CELL_PAD_IN_SITES_DETAIL_PLACEMENT)
 
 set result [catch { detailed_placement_helper -quiet } msg]
 if { $result != 0 } {
-  save_progress 4_1_error
+  orfs_write_db $::env(RESULTS_DIR)/4_1_error.odb
   error "Detailed placement failed in CTS: $msg"
 }
 
 log_cmd estimate_parasitics
 
-if { $::env(CTS_SNAPSHOTS) } {
-  save_progress 4_1_pre_repair_setup_hold
-}
-
 if { !$::env(SKIP_CTS_REPAIR_TIMING) } {
   set lec_enabled [lec_check_enabled]
   if { $lec_enabled } {
@@ -72,7 +62,7 @@ if { !$::env(SKIP_CTS_REPAIR_TIMING) } {
 
   set result [catch { detailed_placement_helper -quiet } msg]
   if { $result != 0 } {
-    save_progress 4_1_error
+    orfs_write_db $::env(RESULTS_DIR)/4_1_error.odb
     error "Detailed placement failed in CTS: $msg"
   }
 

flow/scripts/variables.yaml

@@ -822,12 +822,6 @@ CTS_ARGS:
     Override `clock_tree_synthesis` arguments.
   stages:
     - cts
-CTS_SNAPSHOTS:
-  description: |
-    Create ODB/SDC files at different stages of CTS.
-  stages:
-    - cts
-  default: 0
 HOLD_SLACK_MARGIN:
   description: >
     Specifies a time margin for the slack when fixing hold violations.