netlists-builders: add Build_Pmux.

4 files changed, 67 insertions, 1 deletions

diff --git a/src/synth/netlists-builders.adb b/src/synth/netlists-builders.adb
index 34ba4a3f1..85b2eece9 100644
--- a/src/synth/netlists-builders.adb
+++ b/src/synth/netlists-builders.adb
@@ -426,6 +426,17 @@ package body Netlists.Builders is
         (Ctxt.Design, New_Sname_Artificial (Get_Identifier ("mux4"), No_Sname),
          Id_Mux4, 5, 1, 0);
       Set_Ports_Desc (Ctxt.M_Mux4, Inputs (0 .. 4), Outputs);
+
+      Inputs (0).W := 0;
+      Inputs (1) := Create_Input ("def");
+      Ctxt.M_Pmux := New_User_Module
+        (Ctxt.Design, New_Sname_Artificial (Get_Identifier ("pmux"), No_Sname),
+         Id_Pmux, 2, 1, 1);
+      Set_Ports_Desc (Ctxt.M_Pmux, Inputs (0 .. 1), Outputs);
+      Set_Params_Desc
+        (Ctxt.M_Pmux,
+         (0 => (New_Sname_Artificial (Get_Identifier ("n"), No_Sname),
+                Typ => Param_Uns32)));
    end Create_Mux_Modules;
 
    procedure Create_Objects_Module (Ctxt : Context_Acc)
@@ -1030,6 +1041,24 @@ package body Netlists.Builders is
       return O;
    end Build_Mux4;
 
+   function Build_Pmux (Ctxt : Context_Acc; Sel : Net; Def : Net) return Net
+   is
+      Sel_W : constant Width := Get_Width (Sel);
+      Def_W : constant Width := Get_Width (Def);
+      Inst : Instance;
+      O : Net;
+   begin
+      Inst := New_Var_Instance (Ctxt.Parent, Ctxt.M_Pmux,
+                                New_Internal_Name (Ctxt),
+                                2 + Port_Nbr (Sel_W), 1, 1);
+      Set_Param_Uns32 (Inst, 0, 2 + Sel_W);
+      O := Get_Output (Inst, 0);
+      Set_Width (O, Def_W);
+      Connect (Get_Input (Inst, 0), Sel);
+      Connect (Get_Input (Inst, 1), Def);
+      return O;
+   end Build_Pmux;
+
    function Build_Concat2 (Ctxt : Context_Acc; I0, I1 : Net) return Net
    is
       Inst : Instance;
diff --git a/src/synth/netlists-builders.ads b/src/synth/netlists-builders.ads
index dc45caf04..6a1c0fb82 100644
--- a/src/synth/netlists-builders.ads
+++ b/src/synth/netlists-builders.ads
@@ -96,6 +96,12 @@ package Netlists.Builders is
                         Sel : Net;
                         I0, I1, I2, I3 : Net) return Net;
 
+   --  The width of SEL gives the number of inputs (+ 2).
+   --  The width of DEF (default value) gives the width of the output.
+   function Build_Pmux (Ctxt : Context_Acc;
+                        Sel : Net;
+                        Def : Net) return Net;
+
    --  Build: I0 & I1 [ & I2 [ & I3 ]]
    function Build_Concat2 (Ctxt : Context_Acc; I0, I1 : Net) return Net;
    function Build_Concat3 (Ctxt : Context_Acc; I0, I1, I2 : Net) return Net;
@@ -232,6 +238,7 @@ private
       M_Negedge : Module;
       M_Mux2 : Module;
       M_Mux4 : Module;
+      M_Pmux : Module;
       M_Nop : Module;
       M_Output : Module;
       M_Ioutput : Module;
diff --git a/src/synth/netlists-disp_vhdl.adb b/src/synth/netlists-disp_vhdl.adb
index 41ef62e36..be60f4c19 100644
--- a/src/synth/netlists-disp_vhdl.adb
+++ b/src/synth/netlists-disp_vhdl.adb
@@ -808,6 +808,33 @@ package body Netlists.Disp_Vhdl is
       Put_Line ("  end process;");
    end Disp_Memory;
 
+   procedure Disp_Pmux (Inst : Instance)
+   is
+      Def : constant Net := Get_Input_Net (Inst, 0);
+      W : constant Width := Get_Width (Def);
+      Q : constant Character := Get_Lit_Quote (W);
+   begin
+      Disp_Template ("  with \i0 select \o0 <=" & NL, Inst);
+      for I in 1 .. W loop
+         Put ("    ");
+         Disp_Net_Expr
+           (Get_Input_Net (Inst, Port_Idx (2 + W - I)), Inst, Conv_None);
+         Put (" when ");
+         --  One hot encoding.
+         Put (Q);
+         for J in 1 .. W loop
+            if I = J then
+               Put ('1');
+            else
+               Put ('0');
+            end if;
+         end loop;
+         Put (Q);
+         Put ("," & NL);
+      end loop;
+      Disp_Template ("    \i1 when others;" & NL, Inst);
+   end Disp_Pmux;
+
    procedure Disp_Instance_Inline (Inst : Instance)
    is
       Imod : constant Module := Get_Module (Inst);
@@ -1033,6 +1060,8 @@ package body Netlists.Disp_Vhdl is
             Put ("    ");
             Disp_X_Lit (Get_Width (Get_Output (Inst, 0)), 'X');
             Put_Line (" when others;");
+         when Id_Pmux =>
+            Disp_Pmux (Inst);
          when Id_Add =>
             if Get_Width (Get_Output (Inst, 0)) = 1 then
                Disp_Template ("  \o0 <= \i0 xor \i1;  --  add" & NL, Inst);
diff --git a/src/synth/netlists-utils.adb b/src/synth/netlists-utils.adb
index fa1494820..6a8f1a2bf 100644
--- a/src/synth/netlists-utils.adb
+++ b/src/synth/netlists-utils.adb
@@ -30,7 +30,8 @@ package body Netlists.Utils is
       M : constant Module := Get_Module (Inst);
    begin
       case Get_Id (M) is
-         when Id_Concatn =>
+         when Id_Concatn
+           | Id_Pmux =>
             return Port_Nbr (Get_Param_Uns32 (Inst, 0));
          when others =>
             if Is_Self_Instance (Inst) then