synth: remove remaining clock edge gates after memories.

2 files changed, 26 insertions, 0 deletions

diff --git a/src/synth/netlists-cleanup.adb b/src/synth/netlists-cleanup.adb
index bb963633a..deec7186b 100644
--- a/src/synth/netlists-cleanup.adb
+++ b/src/synth/netlists-cleanup.adb
@@ -202,6 +202,30 @@ package body Netlists.Cleanup is
                   Insert_Mark_And_Sweep (Inspect, Get_Net_Parent (N));
                end if;
             end loop;
+
+            case Get_Id (Inst) is
+               when Id_Mem_Rd
+                 | Id_Mem_Rd_Sync =>
+                  --  When a memory read port is found, mark the whole
+                  --  memory.
+                  --  FIXME: free unused read ports.
+                  declare
+                     Inp : Input;
+                  begin
+                     loop
+                        N := Get_Output (Inst, 0);
+                        Inp := Get_First_Sink (N);
+                        exit when Inp = No_Input;
+                        pragma Assert (Get_Next_Sink (Inp) = No_Input);
+                        Inst := Get_Input_Parent (Inp);
+                        exit when Get_Mark_Flag (Inst);
+                        Insert_Mark_And_Sweep (Inspect, Inst);
+                        N := Get_Output (Inst, 0);
+                     end loop;
+                  end;
+               when others =>
+                  null;
+            end case;
          end;
       end loop;
 
diff --git a/src/synth/synth-insts.adb b/src/synth/synth-insts.adb
index 9e15e04cc..4c9f72fd0 100644
--- a/src/synth/synth-insts.adb
+++ b/src/synth/synth-insts.adb
@@ -1412,6 +1412,8 @@ package body Synth.Insts is
 
       if not Synth.Flags.Flag_Debug_Nomemory then
          Netlists.Memories.Extract_Memories2 (Get_Build (Syn_Inst), Inst.M);
+         --  Remove remaining clock edge gates.
+         Netlists.Cleanup.Mark_And_Sweep (Inst.M);
       end if;
 
       if not Synth.Flags.Flag_Debug_Noexpand then