sdc: Add unrecordExceptionPins(ExceptionPath*) to resolve a crash

include/sta/Sdc.hh

@@ -1115,6 +1115,7 @@ protected:
   void recordMergeHash(ExceptionPath *exception, ExceptionPt *missing_pt);
   void recordMergeHashes(ExceptionPath *exception);
   void unrecordExceptionFirstPts(ExceptionPath *exception);
+  void unrecordExceptionPins(ExceptionPath *exception);
   void unrecordExceptionClks(ExceptionPath *exception,
 			     ClockSet *clks,
 			     ClockExceptionsMap &exception_map);

sdc/Sdc.cc

@@ -4964,6 +4964,7 @@ Sdc::unrecordException(ExceptionPath *exception)
 {
   unrecordMergeHashes(exception);
   unrecordExceptionFirstPts(exception);
+  unrecordExceptionPins(exception);
   exceptions_.erase(exception);
 }
 
@@ -5022,6 +5023,22 @@ Sdc::unrecordExceptionFirstPts(ExceptionPath *exception)
   }
 }
 
+void
+Sdc::unrecordExceptionPins(ExceptionPath *exception)
+{
+  ExceptionFrom *from = exception->from();
+  if (from)
+    unrecordExceptionPins(exception, from->pins(), pin_exceptions_);
+  ExceptionThruSeq *thrus = exception->thrus();
+  if (thrus) {
+    for (ExceptionThru *thru : *thrus)
+      unrecordExceptionPins(exception, thru->pins(), pin_exceptions_);
+  }
+  ExceptionTo *to = exception->to();
+  if (to)
+    unrecordExceptionPins(exception, to->pins(), pin_exceptions_);
+}
+
 void
 Sdc::unrecordExceptionClks(ExceptionPath *exception,
 			   ClockSet *clks,

test/disconnect_pin_with_sdc.ok

@@ -0,0 +1,17 @@
+Warning: asap7_simple.lib.gz line 71029, timing group from output port.
+Warning: asap7_simple.lib.gz line 71505, timing group from output port.
+Warning: asap7_simple.lib.gz line 71981, timing group from output port.
+Warning: asap7_simple.lib.gz line 72457, timing group from output port.
+Warning: asap7_simple.lib.gz line 72933, timing group from output port.
+Warning: asap7_simple.lib.gz line 73409, timing group from output port.
+Warning: asap7_simple.lib.gz line 73885, timing group from output port.
+Warning: asap7_simple.lib.gz line 81795, timing group from output port.
+Warning: asap7_simple.lib.gz line 82271, timing group from output port.
+Warning: asap7_simple.lib.gz line 82747, timing group from output port.
+set_multicycle_path on pins
+Warning: disconnect_pin_with_sdc.tcl line 17, 'u0/buf0/A' is not a valid endpoint.
+Warning: disconnect_pin_with_sdc.tcl line 18, 'u0/buf1/A' is not a valid endpoint.
+Warning: disconnect_pin_with_sdc.tcl line 19, 'u0/buf2/A' is not a valid endpoint.
+Warning: disconnect_pin_with_sdc.tcl line 20, 'u0/buf3/A' is not a valid endpoint.
+disconnect the pin w/ SDC
+Pass

test/disconnect_pin_with_sdc.tcl

@@ -0,0 +1,21 @@
+# disconnect_pin call for a pin where SDC is defined
+read_liberty asap7_small.lib.gz
+read_verilog disconnect_pin_with_sdc.v
+link_design top
+
+create_clock -name clk -period 500 clk
+
+# This SDC defines setup and hold time requirements for data pins
+# relative to a clock, typical for a source-synchronous interface.
+set_data_check -from clk -to [get_pins u0/A] -setup 10
+set_data_check -from clk -to [get_pins u0/A] -hold  10
+set_data_check -from clk -to [get_pins u1/A] -setup 10
+set_data_check -from clk -to [get_pins u1/A] -hold  10
+set_multicycle_path -end   -setup 1 -to [get_pins u0/A]
+set_multicycle_path -end   -setup 1 -to [get_pins u1/A]
+set_multicycle_path -start -hold  0 -to [get_pins u0/A]
+set_multicycle_path -start -hold  0 -to [get_pins u1/A]
+
+set in_pin [get_pins u1/A]
+set in_net [get_net -of $in_pin]
+disconnect_pin $in_net $in_pin

test/disconnect_pin_with_sdc.v

@@ -0,0 +1,11 @@
+module top (clk, clkout, data_in, data_out);
+  input clk;
+  output clkout;
+  input [1:0] data_in;
+  output [1:0] data_out;
+
+  // Anchor buffers on the source-synchronous interface IOs
+  BUFx2_ASAP7_75t_R clkbuf0 (.A(clk), .Y(clkout));
+  BUFx2_ASAP7_75t_R u0 (.A(data_in[0]), .Y(data_out[0]));
+  BUFx2_ASAP7_75t_R u1 (.A(data_in[1]), .Y(data_out[1]));
+endmodule // top

test/regression_vars.tcl

@@ -138,6 +138,7 @@ record_example_tests {
 }
 
 record_sta_tests {
+  disconnect_pin_with_sdc
   get_filter
   get_is_memory
   get_lib_pins_of_objects