Remove REMOVE_ABC_BUFFERS support

docs/user/FlowVariables.md

@@ -246,7 +246,6 @@ configuration file.
 | <a name="PWR_NETS_VOLTAGES"></a>PWR_NETS_VOLTAGES| Used for IR Drop calculation.| |
 | <a name="RCX_RULES"></a>RCX_RULES| RC Extraction rules file path.| |
 | <a name="RECOVER_POWER"></a>RECOVER_POWER| Specifies how many percent of paths with positive slacks can be slowed for power savings [0-100].| 0|
-| <a name="REMOVE_ABC_BUFFERS"></a>REMOVE_ABC_BUFFERS (deprecated)| Remove abc buffers from the netlist. If timing repair in floorplanning is taking too long, use a SETUP/HOLD_SLACK_MARGIN to terminate timing repair early instead of using REMOVE_ABC_BUFFERS or set SKIP_LAST_GASP=1.| 0|
 | <a name="REMOVE_CELLS_FOR_LEC"></a>REMOVE_CELLS_FOR_LEC| String patterns directly passed to write_verilog -remove_cells <> for lec checks.| |
 | <a name="REPAIR_PDN_VIA_LAYER"></a>REPAIR_PDN_VIA_LAYER| Remove power grid vias which generate DRC violations after detailed routing.| |
 | <a name="REPORT_CLOCK_SKEW"></a>REPORT_CLOCK_SKEW| Report clock skew as part of reporting metrics, starting at CTS, before which there is no clock skew. This metric can be quite time-consuming, so it can be useful to disable.| 1|
@@ -431,7 +430,6 @@ configuration file.
 - [PRE_MACRO_PLACE_TCL](#PRE_MACRO_PLACE_TCL)
 - [PRE_PDN_TCL](#PRE_PDN_TCL)
 - [PRE_TAPCELL_TCL](#PRE_TAPCELL_TCL)
-- [REMOVE_ABC_BUFFERS](#REMOVE_ABC_BUFFERS)
 - [ROUTING_LAYER_ADJUSTMENT](#ROUTING_LAYER_ADJUSTMENT)
 - [RTLMP_AREA_WT](#RTLMP_AREA_WT)
 - [RTLMP_ARGS](#RTLMP_ARGS)

flow/scripts/floorplan.tcl

@@ -114,7 +114,7 @@ source_env_var_if_exists FOOTPRINT_TCL
 log_cmd set_dont_use $::env(DONT_USE_CELLS)
 
 # The transforms below (repair_tie_fanout, replace_arith_modules,
-# remove_buffers, repair_timing_helper) look like synthesis-stage
+# repair_timing_helper) look like synthesis-stage
 # operations: they all act on the netlist and don't touch placement.
 # But they DO depend on having a floorplan in place — initialize_floorplan
 # above placed the bterms on the die boundary and set_routing_layers
@@ -151,13 +151,8 @@ if { [env_var_equals SWAP_ARITH_OPERATORS 1] } {
   log_cmd replace_arith_modules
 }
 
-if { $::env(REMOVE_ABC_BUFFERS) } {
-  # remove buffers inserted by yosys/abc
-  log_cmd remove_buffers
-} else {
-  # Skip clone & split
-  repair_timing_helper -setup -skip_last_gasp -sequence "unbuffer,sizeup,swap,vt_swap"
-}
+# Skip clone & split
+repair_timing_helper -setup -skip_last_gasp -sequence "unbuffer,sizeup,swap,vt_swap"
 
 puts "Default units for flow"
 report_units

flow/scripts/variables.yaml

@@ -507,15 +507,6 @@ BUFFER_PORTS_ARGS:
     Specify arguments to the buffer_ports call during placement. Only used if DONT_BUFFER_PORTS=0.
   stages:
     - place
-REMOVE_ABC_BUFFERS:
-  description: >
-    Remove abc buffers from the netlist. If timing repair in floorplanning is
-    taking too long, use a SETUP/HOLD_SLACK_MARGIN to terminate timing repair early
-    instead of using REMOVE_ABC_BUFFERS or set SKIP_LAST_GASP=1.
-  stages:
-    - floorplan
-  deprecated: 1
-  default: 0
 BALANCE_ROWS:
   description: |
     Balance rows during placement.