synth-vhdl_eval: handle find_leftmost and find_rightmost

3 files changed, 55 insertions, 0 deletions

diff --git a/src/synth/synth-ieee-numeric_std.adb b/src/synth/synth-ieee-numeric_std.adb
index ad41757fc..0e1b4be0e 100644
--- a/src/synth/synth-ieee-numeric_std.adb
+++ b/src/synth/synth-ieee-numeric_std.adb
@@ -1495,4 +1495,43 @@ package body Synth.Ieee.Numeric_Std is
       return Res;
    end Minmax;
 
+   function Offset_To_Index (Off : Int32; Typ : Type_Acc) return Int32 is
+   begin
+      case Typ.Abound.Dir is
+         when Dir_To =>
+            return Typ.Abound.Left + Off;
+         when Dir_Downto =>
+            return Typ.Abound.Left - Off;
+      end case;
+   end Offset_To_Index;
+
+   function Find_Rightmost (Arg : Memtyp; Val : Memtyp) return Int32
+   is
+      Len : constant Uns32 := Arg.Typ.Abound.Len;
+      Y : Std_Ulogic;
+   begin
+      Y := Read_Std_Logic (Val.Mem, 0);
+
+      for I in reverse 1 .. Len loop
+         if Match_Eq_Table (Read_Std_Logic (Arg.Mem, I - 1), Y) = '1' then
+            return Offset_To_Index (Int32 (I - 1), Arg.Typ);
+         end if;
+      end loop;
+      return -1;
+   end Find_Rightmost;
+
+   function Find_Leftmost (Arg : Memtyp; Val : Memtyp) return Int32
+   is
+      Len : constant Uns32 := Arg.Typ.Abound.Len;
+      Y : Std_Ulogic;
+   begin
+      Y := Read_Std_Logic (Val.Mem, 0);
+
+      for I in 1 .. Len loop
+         if Match_Eq_Table (Read_Std_Logic (Arg.Mem, I - 1), Y) = '1' then
+            return Offset_To_Index (Int32 (I - 1), Arg.Typ);
+         end if;
+      end loop;
+      return -1;
+   end Find_Leftmost;
 end Synth.Ieee.Numeric_Std;
diff --git a/src/synth/synth-ieee-numeric_std.ads b/src/synth/synth-ieee-numeric_std.ads
index 22616986e..4c5888463 100644
--- a/src/synth/synth-ieee-numeric_std.ads
+++ b/src/synth/synth-ieee-numeric_std.ads
@@ -130,4 +130,7 @@ package Synth.Ieee.Numeric_Std is
    function Minmax (L, R : Memtyp; Is_Signed : Boolean; Is_Max : Boolean)
                    return Memtyp;
 
+   --  Find_Rightmost/Find_Leftmost
+   function Find_Rightmost (Arg : Memtyp; Val : Memtyp) return Int32;
+   function Find_Leftmost (Arg : Memtyp; Val : Memtyp) return Int32;
 end Synth.Ieee.Numeric_Std;
diff --git a/src/synth/synth-vhdl_eval.adb b/src/synth/synth-vhdl_eval.adb
index 6b4788556..f69fe6192 100644
--- a/src/synth/synth-vhdl_eval.adb
+++ b/src/synth/synth-vhdl_eval.adb
@@ -2082,6 +2082,19 @@ package body Synth.Vhdl_Eval is
             return Minmax (Get_Memtyp (Param1), Get_Memtyp (Param2),
                            True, False);
 
+         when Iir_Predefined_Ieee_Numeric_Std_Find_Rightmost_Uns
+            | Iir_Predefined_Ieee_Numeric_Std_Find_Rightmost_Sgn =>
+            return Create_Memory_Discrete
+              (Int64 (Find_Rightmost (Get_Memtyp (Param1),
+                                      Get_Memtyp (Param2))),
+               Res_Typ);
+         when Iir_Predefined_Ieee_Numeric_Std_Find_Leftmost_Uns
+            | Iir_Predefined_Ieee_Numeric_Std_Find_Leftmost_Sgn =>
+            return Create_Memory_Discrete
+              (Int64 (Find_Leftmost (Get_Memtyp (Param1),
+                                     Get_Memtyp (Param2))),
+               Res_Typ);
+
          when Iir_Predefined_Ieee_Math_Real_Log2 =>
             declare
                function Log2 (Arg : Fp64) return Fp64;