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authorTristan Gingold <tgingold@free.fr>2023-04-17 08:36:00 +0200
committerTristan Gingold <tgingold@free.fr>2023-04-17 08:48:09 +0200
commit65e59f6ca536e1bb87212dfbd75743f541e4ef59 (patch)
treedbd9bacd5920a82cffd56b3f41d7136dfb5fa237 /src
parent334fe4177c5363d1a9c4571a596343dd17987fc1 (diff)
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netlists-memories: factorize code
Diffstat (limited to 'src')
-rw-r--r--src/synth/netlists-memories.adb101
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);