diff options
| -rw-r--r-- | src/synth/synth-environment.ads | 35 | ||||
| -rw-r--r-- | src/synth/synth-stmts.adb | 144 |
2 files changed, 120 insertions, 59 deletions
diff --git a/src/synth/synth-environment.ads b/src/synth/synth-environment.ads index ec76f515a..74d0c3350 100644 --- a/src/synth/synth-environment.ads +++ b/src/synth/synth-environment.ads @@ -167,7 +167,22 @@ package Synth.Environment is type Partial_Assign is private; No_Partial_Assign : constant Partial_Assign; - type Seq_Assign_Value is private; + type Seq_Assign_Value (Is_Static : Tri_State_Type := True) is record + case Is_Static is + when Unknown => + -- Used only for no value (in that case, it will use the previous + -- value). + -- This is used only for temporary handling, and is never stored + -- in Seq_Assign. + null; + when True => + Val : Memtyp; + when False => + -- Values assigned. + Asgns : Partial_Assign; + end case; + end record; + No_Seq_Assign_Value : constant Seq_Assign_Value; function Get_Assign_Partial (Asgn : Seq_Assign) return Partial_Assign; @@ -188,6 +203,8 @@ package Synth.Environment is procedure Partial_Assign_Init (List : out Partial_Assign_List); procedure Partial_Assign_Append (List : in out Partial_Assign_List; Pasgn : Partial_Assign); + + -- Phi_Assign for each element of LIST. procedure Merge_Partial_Assigns (Ctxt : Builders.Context_Acc; Wid : Wire_Id; List : in out Partial_Assign_List); @@ -277,22 +294,6 @@ private Nbr_Final_Assign : Natural; end record; - type Seq_Assign_Value (Is_Static : Tri_State_Type := True) is record - case Is_Static is - when Unknown => - -- Used only for no value (in that case, it will use the previous - -- value). - -- This is used only for temporary handling, and is never stored - -- in Seq_Assign. - null; - when True => - Val : Memtyp; - when False => - -- Values assigned. - Asgns : Partial_Assign; - end case; - end record; - No_Seq_Assign_Value : constant Seq_Assign_Value := (Is_Static => Unknown); type Seq_Assign_Record is record diff --git a/src/synth/synth-stmts.adb b/src/synth/synth-stmts.adb index 1666bcf24..6217cbbb6 100644 --- a/src/synth/synth-stmts.adb +++ b/src/synth/synth-stmts.adb @@ -1041,6 +1041,7 @@ package body Synth.Stmts is Min_Off, Off : Uns32; Wd : Width; List : Partial_Assign_List; + Sval : Memtyp; begin -- Extract the value for each branch. for I in Alts'Range loop @@ -1055,53 +1056,112 @@ package body Synth.Stmts is end if; end loop; - -- Compute the final value for each partial part of the wire. - Partial_Assign_Init (List); - Min_Off := 0; - loop - Off := Min_Off; - - -- Extract value of partial assignments to NETS. - Extract_Merge_Partial_Assigns - (Build_Context, Pasgns.all, Nets.all, Off, Wd); - exit when Off = Uns32'Last and Wd = Width'Last; - - -- If a branch has no value, use the value before the case. - Last_Val := No_Net; - for I in Nets'Range loop - if Nets (I) = No_Net then - if Last_Val = No_Net then - Last_Val := Get_Current_Assign_Value - (Build_Context, Wi, Off, Wd); + -- If: + -- 1) All present values in PASGNS are static + -- 2) There is no missing values *or* the previous value is + -- static. + -- 3) The default value is unused *or* it is static + -- 4) All the values are equal. + -- then assign directly. + Sval := Null_Memtyp; + declare + Prev_Val : Memtyp; + begin + Prev_Val := Null_Memtyp; + for I in Pasgns'Range loop + case Pasgns (I).Is_Static is + when False => + Sval := Null_Memtyp; + -- It's over. + exit; + when Unknown => + if Prev_Val = Null_Memtyp then + if not Is_Static_Wire (Wi) then + Sval := Null_Memtyp; + -- It's over. + exit; + end if; + Prev_Val := Get_Static_Wire (Wi); + end if; + if Sval /= Null_Memtyp + and then not Is_Equal (Sval, Prev_Val) + then + Sval := Null_Memtyp; + -- It's over. + exit; + end if; + when True => + if Sval = Null_Memtyp then + Sval := Pasgns (I).Val; + if Prev_Val /= Null_Memtyp + and then not Is_Equal (Sval, Prev_Val) + then + Sval := Null_Memtyp; + -- It's over. + exit; + end if; + else + if not Is_Equal (Sval, Pasgns (I).Val) then + Sval := Null_Memtyp; + -- It's over. + exit; + end if; + end if; + end case; + end loop; + end; + if Sval /= Null_Memtyp then + Phi_Assign_Static (Wi, Sval); + else + -- Compute the final value for each partial part of the wire. + Partial_Assign_Init (List); + Min_Off := 0; + loop + Off := Min_Off; + + -- Extract value of partial assignments to NETS. + Extract_Merge_Partial_Assigns + (Build_Context, Pasgns.all, Nets.all, Off, Wd); + exit when Off = Uns32'Last and Wd = Width'Last; + + -- If a branch has no value, use the value before the case. + Last_Val := No_Net; + for I in Nets'Range loop + if Nets (I) = No_Net then + if Last_Val = No_Net then + Last_Val := Get_Current_Assign_Value + (Build_Context, Wi, Off, Wd); + end if; + Nets (I) := Last_Val; end if; - Nets (I) := Last_Val; + end loop; + + -- Build the map between choices and values. + for J in Annex_Arr'Range loop + Ch := Natural (Annex_Arr (J)); + Case_El (J) := + (Sel => Choice_Data (Ch).Val, + Val => Nets (Int32 (Choice_Data (Ch).Alt))); + end loop; + + -- Extract default value (for missing alternative). + if Others_Alt_Idx /= 0 then + Default := Nets (Int32 (Others_Alt_Idx)); + else + Default := No_Net; end if; - end loop; - -- Build the map between choices and values. - for J in Annex_Arr'Range loop - Ch := Natural (Annex_Arr (J)); - Case_El (J) := (Sel => Choice_Data (Ch).Val, - Val => Nets (Int32 (Choice_Data (Ch).Alt))); - end loop; - - -- Extract default value (for missing alternative). - if Others_Alt_Idx /= 0 then - Default := Nets (Int32 (Others_Alt_Idx)); - else - Default := No_Net; - end if; + -- Generate the muxes tree. + Synth_Case (Get_Build (C.Inst), + Sel_Net, Case_El.all, Default, Res, + Get_Location (Expr)); - -- Generate the muxes tree. - Synth_Case (Get_Build (C.Inst), - Sel_Net, Case_El.all, Default, Res, - Get_Location (Expr)); - - Partial_Assign_Append (List, New_Partial_Assign (Res, Off)); - Min_Off := Off + Wd; - end loop; + Partial_Assign_Append (List, New_Partial_Assign (Res, Off)); + Min_Off := Off + Wd; + end loop; - Merge_Partial_Assigns (Build_Context, Wi, List); + Merge_Partial_Assigns (Build_Context, Wi, List); + end if; end; end loop; |