diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/synth/netlists-memories.adb | 101 |
1 files changed, 27 insertions, 74 deletions
diff --git a/src/synth/netlists-memories.adb b/src/synth/netlists-memories.adb index 1502b6f40..ccce168ec 100644 --- a/src/synth/netlists-memories.adb +++ b/src/synth/netlists-memories.adb @@ -1023,89 +1023,43 @@ package body Netlists.Memories is -- VAL is the output of the dyn_extract. -- -- Infere a synchronous read if the dyn_extract is connected to a dff. - function Create_ROM_Read_Port - (Ctxt : Context_Acc; Last : Net; Addr : Net; Val : Net; Step : Width) - return Instance + function Create_ROM_Read_Port (Ctxt : Context_Acc; + Last : Net; + Addr : Net; + Extr_Inst : Instance; + Step : Width) return Instance is + Val : constant Net := Get_Output (Extr_Inst, 0); W : constant Width := Get_Width (Val); Res : Instance; - Inp : Input; - Iinst : Instance; + Dff_Inst : Instance; N : Net; + Clk : Net; + En : Net; begin - Inp := Get_First_Sink (Val); - if Get_Next_Sink (Inp) = No_Input then - -- There is a single input. - Iinst := Get_Input_Parent (Inp); - if Get_Id (Iinst) = Id_Dff then - -- The output of the dyn_extract is directly connected to a dff. - -- So this is a synchronous read without enable. - declare - Clk_Inp : Input; - Clk : Net; - En : Net; - begin - Clk_Inp := Get_Input (Iinst, 0); - Clk := Get_Driver (Clk_Inp); - Disconnect (Clk_Inp); - En := Build_Const_UB32 (Ctxt, 1, 1); - Disconnect (Inp); - Res := Build_Mem_Rd_Sync (Ctxt, Last, Addr, Clk, En, Step); - - -- Slice the output. - N := Get_Output (Res, 1); - N := Build2_Extract (Ctxt, N, 0, W); - - Redirect_Inputs (Get_Output (Iinst, 0), N); - Remove_Instance (Iinst); - return Res; - end; - elsif Get_Id (Iinst) = Id_Mux2 and then Is_Enable_Dff (Inp) then - declare - Mux_Out : constant Net := Get_Output (Iinst, 0); - Mux_En_Inp : constant Input := Get_Input (Iinst, 0); - Mux_I0_Inp : constant Input := Get_Input (Iinst, 1); - Mux_I1_Inp : constant Input := Get_Input (Iinst, 2); - Dff_Din : constant Input := Get_First_Sink (Mux_Out); - Dff_Inst : constant Instance := Get_Input_Parent (Dff_Din); - Dff_Out : constant Net := Get_Output (Dff_Inst, 0); - Clk_Inp : constant Input := Get_Input (Dff_Inst, 0); - Clk : constant Net := Get_Driver (Clk_Inp); - En : Net; - begin - En := Get_Driver (Mux_En_Inp); - if Dff_Out = Get_Driver (Mux_I1_Inp) then - En := Build_Monadic (Ctxt, Id_Not, En); - Copy_Location (En, Dff_Inst); - end if; - Disconnect (Mux_En_Inp); - Disconnect (Mux_I0_Inp); - Disconnect (Mux_I1_Inp); - Disconnect (Dff_Din); - Disconnect (Clk_Inp); - Remove_Instance (Iinst); - Res := Build_Mem_Rd_Sync (Ctxt, Last, Addr, Clk, En, Step); - Set_Location (Res, Get_Location (Dff_Inst)); - - -- Slice the output. - N := Get_Output (Res, 1); - N := Build2_Extract (Ctxt, N, 0, W); - - Redirect_Inputs (Dff_Out, N); - Remove_Instance (Dff_Inst); - return Res; - end; + Extract_Extract_Dff (Ctxt, Extr_Inst, Dff_Inst, Clk, En); + if Dff_Inst /= Extr_Inst then + -- There was a dff, so the read port is synchronous. + if En = No_Net then + En := Build_Const_UB32 (Ctxt, 1, 1); end if; - end if; - -- Replace Dyn_Extract with mem_rd. - Res := Build_Mem_Rd (Ctxt, Last, Addr, Step); + Res := Build_Mem_Rd_Sync (Ctxt, Last, Addr, Clk, En, Step); + else + -- Replace Dyn_Extract with mem_rd (asynchronous read port). + Res := Build_Mem_Rd (Ctxt, Last, Addr, Step); + end if; -- Slice the output. N := Get_Output (Res, 1); N := Build2_Extract (Ctxt, N, 0, W); - Redirect_Inputs (Val, N); + if Dff_Inst /= Extr_Inst then + Redirect_Inputs (Get_Output (Dff_Inst, 0), N); + Remove_Instance (Dff_Inst); + else + Redirect_Inputs (Get_Output (Extr_Inst, 0), N); + end if; return Res; end Create_ROM_Read_Port; @@ -1121,7 +1075,6 @@ package body Netlists.Memories is Extr_Inst : Instance; Addr_Inp : Input; Addr : Net; - Val : Net; Port_Inst : Instance; begin Last := Get_Output (Mem_Inst, 0); @@ -1146,11 +1099,11 @@ package body Netlists.Memories is Addr_Inp := Get_Input (Extr_Inst, 1); Addr := Get_Driver (Addr_Inp); Disconnect (Addr_Inp); - Val := Get_Output (Extr_Inst, 0); Convert_Memidx (Ctxt, Orig, Addr, Step); -- Replace Dyn_Extract with mem_rd. - Port_Inst := Create_ROM_Read_Port (Ctxt, Last, Addr, Val, Step); + Port_Inst := Create_ROM_Read_Port + (Ctxt, Last, Addr, Extr_Inst, Step); Remove_Instance (Extr_Inst); |