diff options
| -rw-r--r-- | src/grt/grt-signals.adb | 37 | ||||
| -rw-r--r-- | src/grt/grt-signals.ads | 1 |
2 files changed, 34 insertions, 4 deletions
diff --git a/src/grt/grt-signals.adb b/src/grt/grt-signals.adb index 2f10589fc..363e7977e 100644 --- a/src/grt/grt-signals.adb +++ b/src/grt/grt-signals.adb @@ -2146,6 +2146,7 @@ package body Grt.Signals is -- Not resolved (so at most one source). if Sig.S.Nbr_Drivers = 1 then -- Not resolved, 1 source : a driver. + pragma Assert (Sig.Nbr_Ports = 0); if Is_Eff_Drv (Sig) then Add_Propagation ((Kind => Eff_One_Driver, Sig => Sig)); Sig.Flags.Propag := Propag_Done; @@ -2156,6 +2157,8 @@ package body Grt.Signals is else Sig.Flags.Propag := Propag_Being_Driving; -- not resolved, 1 source : Source is a port. + pragma Assert (Sig.Nbr_Ports = 1); + pragma Assert (Sig.S.Nbr_Drivers = 0); Order_Signal (Sig.Ports (0), Propag_Driving); if Is_Eff_Drv (Sig) then Add_Propagation ((Kind => Eff_One_Port, Sig => Sig)); @@ -2672,6 +2675,9 @@ package body Grt.Signals is else Sig.Net := Net_One_Driver; end if; + else + pragma Assert (Sig.S.Nbr_Drivers = 0); + null; end if; else Sig.Net := Offs (Sig.Net); @@ -2780,6 +2786,9 @@ package body Grt.Signals is -- Add SIG in active_chain while the signal is being assigned while -- processes are executed. So SIG has to be considered during the update -- phase. + -- + -- It is also used internally by Run_Propagation to keep the list of nets + -- whose update flag has to be cleared. procedure Add_Active_Chain (Sig : Ghdl_Signal_Ptr); pragma Inline (Add_Active_Chain); @@ -3013,7 +3022,10 @@ package body Grt.Signals is return; end if; + -- Set the updated flag, so that propagation is run only once. Propagation.Table (Net).Updated := True; + -- And put it on the active chain to clear the update flag (this is not + -- the regular use of the active chain). Add_Active_Chain (Sig_Net); I := Net + 1; @@ -3171,17 +3183,27 @@ package body Grt.Signals is when Imp_Stable | Imp_Quiet => Sig := Propagation.Table (I).Sig; + -- Mark Sig active if one of its source is active (Imp_Quiet) + -- or has an event (Imp_Stable). Set_Stable_Quiet_Activity (Propagation.Table (I).Kind, Sig); if Sig.Active then + -- Set driver. + -- LRM02 12.6.3 + -- If an event has occurred on signal S, then S'Stable(T) is + -- updated by assigning the value FALSE to the variable + -- representing the current value of S'Table(T), ... Sig.Driving_Value := Value_Union'(Mode => Mode_B1, B1 => False); - -- Set driver. + -- LRM02 12.6.3 + -- ... and the driver of S'Stable(T) is a assigned the + -- waveform TRUE after T. Trans := new Transaction' (Kind => Trans_Value, Line => 0, Time => Current_Time + Sig.S.Time, Next => null, Val => Value_Union'(Mode => Mode_B1, B1 => True)); + -- Remove previous transaction. if Sig.S.Attr_Trans.Next /= null then Free (Sig.S.Attr_Trans.Next); end if; @@ -3192,6 +3214,11 @@ package body Grt.Signals is Add_Active_Chain (Sig); end if; else + -- LRM02 12.6.3 + -- Otherwise, if the driver of S'Stable(T) is active, then + -- S'Stable(T) is updated by assigning the current value of + -- the driver to the variable representing the current value + -- of S'Stable(T). Trans := Sig.S.Attr_Trans.Next; if Trans /= null and then Trans.Time = Current_Time then Mark_Active (Sig); @@ -3282,7 +3309,8 @@ package body Grt.Signals is Trans : Transaction_Acc; begin -- LRM93 12.6.2 - -- 1) Reset active flag. + -- 1) Reset active flag: all signals active in the previous cycle are + -- not anymore active. Reset_Active_Flag; -- Forced signals. @@ -3314,9 +3342,11 @@ package body Grt.Signals is end; end if; - -- For each active signals + -- Extract and reset the chain of active signals. Sig := Ghdl_Signal_Active_Chain; Ghdl_Signal_Active_Chain := Signal_End; + + -- For each active signals. while Sig.S.Mode_Sig /= Mode_End loop Next_Sig := Sig.Link; Sig.Link := null; @@ -3377,7 +3407,6 @@ package body Grt.Signals is Internal_Error ("update_signals: no_signal_net"); when Signal_Net_Defined => - -- Mark_Active (Sig); Sig.Flags.Is_Direct_Active := False; Run_Propagation (Sig); end case; diff --git a/src/grt/grt-signals.ads b/src/grt/grt-signals.ads index a74399214..195036fde 100644 --- a/src/grt/grt-signals.ads +++ b/src/grt/grt-signals.ads @@ -224,6 +224,7 @@ package Grt.Signals is type Signal_Net_Type is new Integer range -3 .. Integer'Last; subtype Signal_Net_Defined is Signal_Net_Type range 1 .. Signal_Net_Type'Last; + -- No propagation for the signals on these nets: No_Signal_Net : constant Signal_Net_Type := 0; Net_One_Driver : constant Signal_Net_Type := -1; Net_One_Direct : constant Signal_Net_Type := -2; |