openieee: use .vhdl extension

1 files changed, 0 insertions, 2333 deletions

diff --git a/libraries/openieee/numeric_bit-body.v87 b/libraries/openieee/numeric_bit-body.v87
deleted file mode 100644
index 3bdc634ac..000000000
--- a/libraries/openieee/numeric_bit-body.v87
+++ /dev/null
@@ -1,2333 +0,0 @@
---  This -*- vhdl -*- file was generated from numeric_bit-body.proto
---  This -*- vhdl -*- file is part of GHDL.
---  IEEE 1076.3 compliant numeric bit package body.
---  The implementation is based only on the specifications.
---  Copyright (C) 2015 Tristan Gingold
---
---  GHDL is free software; you can redistribute it and/or modify it under
---  the terms of the GNU General Public License as published by the Free
---  Software Foundation; either version 2, or (at your option) any later
---  version.
---
---  GHDL is distributed in the hope that it will be useful, but WITHOUT ANY
---  WARRANTY; without even the implied warranty of MERCHANTABILITY or
---  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
---  for more details.
---
---  You should have received a copy of the GNU General Public License
---  along with GCC; see the file COPYING2.  If not see
---  <http://www.gnu.org/licenses/>.
-
-package body NUMERIC_BIT is
-  constant NO_WARNING : Boolean := False;
-
-  constant null_unsigned : unsigned (0 downto 1) := (others => '0');
-  constant null_signed   :   signed (0 downto 1) := (others => '0');
-
-  subtype nat1 is natural range 0 to 1;
-
-  type nat1_to_sl_type is array (nat1) of bit;
-  constant nat1_to_01 : nat1_to_sl_type := (0 => '0', 1 => '1');
-
-  subtype sl_01 is bit;
-
-  type carry_array is array (sl_01, sl_01, sl_01) of sl_01;
-  constant compute_carry : carry_array :=
-    ('0' => ('0' => ('0' => '0', '1' => '0'),
-             '1' => ('0' => '0', '1' => '1')),
-     '1' => ('0' => ('0' => '0', '1' => '1'),
-             '1' => ('0' => '1', '1' => '1')));
-  constant compute_sum : carry_array :=
-    ('0' => ('0' => ('0' => '0', '1' => '1'),
-             '1' => ('0' => '1', '1' => '0')),
-     '1' => ('0' => ('0' => '1', '1' => '0'),
-             '1' => ('0' => '0', '1' => '1')));
-
-  type compare_type is (compare_unknown,
-                        compare_lt,
-                        compare_eq,
-                        compare_gt);
-
-  function MAX (L, R : natural) return natural is
-  begin
-    if L > R then
-      return L;
-    else
-      return R;
-    end if;
-  end MAX;
-
-  function TO_INTEGER (ARG : UNSIGNED) return NATURAL
-  is
-    variable res : natural := 0;
-  begin
-    if arg'length = 0 then
-      assert NO_WARNING
-        report "NUMERIC_BIT.TO_INTEGER: null array detected, returning 0"
-        severity warning;
-      return 0;
-    end if;
-
-    for i in arg'range loop
-      res := res + res;
-      if arg (i) = '1' then
-        res := res + 1;
-      end if;
-    end loop;
-
-    return res;
-  end TO_INTEGER;
-
-  function TO_INTEGER (ARG :   SIGNED) return INTEGER
-  is
-    alias argn : SIGNED (ARG'Length -1 downto 0) is arg;
-    variable res : integer := 0;
-    variable b : bit;
-  begin
-    if argn'length = 0 then
-      assert NO_WARNING
-        report "NUMERIC_BIT.TO_INTEGER: null array detected, returning 0"
-        severity warning;
-      return 0;
-    end if;
-    if argn (argn'left) = '1' then
-      --  Negative value
-      b := '0';
-    else
-      b := '1';
-    end if;
-
-    for i in argn'range loop
-      res := res + res;
-      if argn (i) = b then
-        res := res + 1;
-      end if;
-    end loop;
-
-    if b = '0' then
-      --  Avoid overflow.
-      res := -res - 1;
-    end if;
-
-    return res;
-  end TO_INTEGER;
-
-  function TO_UNSIGNED (ARG, SIZE : NATURAL) return UNSIGNED
-  is
-    variable res : UNSIGNED (SIZE - 1 downto 0);
-    variable a : natural := arg;
-    variable d : nat1;
-  begin
-    if size = 0 then
-      return null_unsigned;
-    end if;
-    for i in res'reverse_range loop
-      d := a rem 2;
-      res (i) := nat1_to_01 (d);
-      a := a / 2;
-    end loop;
-    if a /= 0 then
-      assert NO_WARNING
-        report "NUMERIC_BIT.TO_UNSIGNED: vector is truncated"
-        severity warning;
-    end if;
-    return res;
-  end TO_UNSIGNED;
-
-  function TO_SIGNED (ARG : INTEGER; SIZE : NATURAL) return SIGNED
-  is
-    variable res : SIGNED (SIZE - 1 downto 0);
-    variable v : integer := arg;
-    variable b0, b1 : bit;
-    variable d : nat1;
-  begin
-    if size = 0 then
-      return null_signed;
-    end if;
-    if arg < 0 then
-      --  Use one complement to avoid overflow:
-      --   -v = (not v) + 1
-      --   not v = -v - 1
-      --   not v = -(v + 1)
-      v := -(arg + 1);
-      b0 := '1';
-      b1 := '0';
-    else
-      v := arg;
-      b0 := '0';
-      b1 := '1';
-    end if;
-
-    for i in res'reverse_range loop
-      d := v rem 2;
-      v := v / 2;
-      if d = 0 then
-        res (i) := b0;
-      else
-        res (i) := b1;
-      end if;
-    end loop;
-    if v /= 0 or res (res'left) /= b0 then
-      assert NO_WARNING
-        report "NUMERIC_BIT.TO_SIGNED: vector is truncated"
-        severity warning;
-    end if;
-    return res;
-  end TO_SIGNED;
-
-
-  function "+" (l, r : UNSIGNED) return UNSIGNED
-  is
-    constant lft : integer := MAX (l'length, r'length) - 1;
-    subtype res_type is UNSIGNED (lft downto 0);
-    alias la : UNSIGNED (l'length - 1 downto 0) is l;
-    alias ra : UNSIGNED (r'length - 1 downto 0) is r;
-    variable res : res_type;
-    variable lb, rb, carry : bit;
-  begin
-    if la'left < 0 or ra'left < 0 then
-       return null_UNSIGNED;
-    end if;
-    carry := '0';
-    for i in 0 to lft loop
-       if i > la'left then
-          lb := '0';
-       else
-          lb := la (i);
-       end if;
-       if i > ra'left then
-          rb := '0';
-       else
-          rb := ra (i);
-       end if;
-      res (i) := compute_sum (carry, rb, lb);
-      carry := compute_carry (carry, rb, lb);
-    end loop;
-    return res;
-  end "+";
-
-  function "+" (l, r : SIGNED) return SIGNED
-  is
-    constant lft : integer := MAX (l'length, r'length) - 1;
-    subtype res_type is SIGNED (lft downto 0);
-    alias la : SIGNED (l'length - 1 downto 0) is l;
-    alias ra : SIGNED (r'length - 1 downto 0) is r;
-    variable res : res_type;
-    variable lb, rb, carry : bit;
-  begin
-    if la'left < 0 or ra'left < 0 then
-       return null_SIGNED;
-    end if;
-    carry := '0';
-    for i in 0 to lft loop
-       if i > la'left then
-          lb := l (l'left);
-       else
-          lb := la (i);
-       end if;
-       if i > ra'left then
-          rb := r (r'left);
-       else
-          rb := ra (i);
-       end if;
-      res (i) := compute_sum (carry, rb, lb);
-      carry := compute_carry (carry, rb, lb);
-    end loop;
-    return res;
-  end "+";
-
-  function "+" (l : UNSIGNED; r : NATURAL) return UNSIGNED
-  is
-    subtype res_type is UNSIGNED (l'length - 1 downto 0);
-    alias la : res_type is l;
-     variable r1, r2 : NATURAL;
-     variable rd : nat1;
-    variable res : res_type;
-    variable lb, rb, carry : bit;
-  begin
-    if res'length < 0 then
-       return null_UNSIGNED;
-    end if;
-    carry := '0';
-    r1 := r;
-    for i in res'reverse_range loop
-       lb := la (i);
-
-       r2 := r1 / 2;
-       rd := r1 - 2 * r2;
-       r1 := r2;
-       rb := nat1_to_01 (rd);
-      res (i) := compute_sum (carry, rb, lb);
-      carry := compute_carry (carry, rb, lb);
-    end loop;
-    if r1 /= 0 then
-      assert NO_WARNING
-        report "NUMERIC_STD.""+"": vector is truncated"
-        severity warning;
-    end if;
-    return res;
-  end "+";
-
-  function "+" (l : NATURAL; r : UNSIGNED) return UNSIGNED
-  is
-    subtype res_type is UNSIGNED (r'length - 1 downto 0);
-    alias ra : res_type is r;
-     variable l1, l2 : NATURAL;
-     variable ld : nat1;
-    variable res : res_type;
-    variable lb, rb, carry : bit;
-  begin
-    if res'length < 0 then
-       return null_UNSIGNED;
-    end if;
-    carry := '0';
-    l1 := l;
-    for i in res'reverse_range loop
-       rb := ra (i);
-
-       l2 := l1 / 2;
-       ld := l1 - 2 * l2;
-       l1 := l2;
-       lb := nat1_to_01 (ld);
-      res (i) := compute_sum (carry, rb, lb);
-      carry := compute_carry (carry, rb, lb);
-    end loop;
-    if l1 /= 0 then
-      assert NO_WARNING
-        report "NUMERIC_STD.""+"": vector is truncated"
-        severity warning;
-    end if;
-    return res;
-  end "+";
-
-  function "+" (l : SIGNED; r : INTEGER) return SIGNED
-  is
-    subtype res_type is SIGNED (l'length - 1 downto 0);
-    alias la : res_type is l;
-     variable r1, r2 : INTEGER;
-     variable rd : nat1;
-     constant rmsb : nat1 := boolean'pos(r < 0);
-    variable res : res_type;
-    variable lb, rb, carry : bit;
-  begin
-    if res'length < 0 then
-       return null_SIGNED;
-    end if;
-    carry := '0';
-    r1 := r;
-    for i in res'reverse_range loop
-       lb := la (i);
-
-       r2 := r1 / 2;
-       if r1 < 0 then
-          rd := 2 * r2 - r1;
-          r1 := r2 - rd;
-        else
-          rd := r1 - 2 * r2;
-          r1 := r2;
-        end if;
-       rb := nat1_to_01 (rd);
-      res (i) := compute_sum (carry, rb, lb);
-      carry := compute_carry (carry, rb, lb);
-    end loop;
-    if r1 /= -rmsb then
-      assert NO_WARNING
-        report "NUMERIC_STD.""+"": vector is truncated"
-        severity warning;
-    end if;
-    return res;
-  end "+";
-
-  function "+" (l : INTEGER; r : SIGNED) return SIGNED
-  is
-    subtype res_type is SIGNED (r'length - 1 downto 0);
-    alias ra : res_type is r;
-     variable l1, l2 : INTEGER;
-     variable ld : nat1;
-     constant lmsb : nat1 := boolean'pos(l < 0);
-    variable res : res_type;
-    variable lb, rb, carry : bit;
-  begin
-    if res'length < 0 then
-       return null_SIGNED;
-    end if;
-    carry := '0';
-    l1 := l;
-    for i in res'reverse_range loop
-       rb := ra (i);
-
-       l2 := l1 / 2;
-       if l1 < 0 then
-          ld := 2 * l2 - l1;
-          l1 := l2 - ld;
-        else
-          ld := l1 - 2 * l2;
-          l1 := l2;
-        end if;
-       lb := nat1_to_01 (ld);
-      res (i) := compute_sum (carry, rb, lb);
-      carry := compute_carry (carry, rb, lb);
-    end loop;
-    if l1 /= -lmsb then
-      assert NO_WARNING
-        report "NUMERIC_STD.""+"": vector is truncated"
-        severity warning;
-    end if;
-    return res;
-  end "+";
-
-  function "-" (l, r : UNSIGNED) return UNSIGNED
-  is
-    constant lft : integer := MAX (l'length, r'length) - 1;
-    subtype res_type is UNSIGNED (lft downto 0);
-    alias la : UNSIGNED (l'length - 1 downto 0) is l;
-    alias ra : UNSIGNED (r'length - 1 downto 0) is r;
-    variable res : res_type;
-    variable lb, rb, carry : bit;
-  begin
-    if la'left < 0 or ra'left < 0 then
-       return null_UNSIGNED;
-    end if;
-    carry := '1';
-    for i in 0 to lft loop
-       if i > la'left then
-          lb := '0';
-       else
-          lb := la (i);
-       end if;
-       if i > ra'left then
-          rb := '0';
-       else
-          rb := ra (i);
-       end if;
-      rb := not rb;
-      res (i) := compute_sum (carry, rb, lb);
-      carry := compute_carry (carry, rb, lb);
-    end loop;
-    return res;
-  end "-";
-
-  function "-" (l, r : SIGNED) return SIGNED
-  is
-    constant lft : integer := MAX (l'length, r'length) - 1;
-    subtype res_type is SIGNED (lft downto 0);
-    alias la : SIGNED (l'length - 1 downto 0) is l;
-    alias ra : SIGNED (r'length - 1 downto 0) is r;
-    variable res : res_type;
-    variable lb, rb, carry : bit;
-  begin
-    if la'left < 0 or ra'left < 0 then
-       return null_SIGNED;
-    end if;
-    carry := '1';
-    for i in 0 to lft loop
-       if i > la'left then
-          lb := l (l'left);
-       else
-          lb := la (i);
-       end if;
-       if i > ra'left then
-          rb := r (r'left);
-       else
-          rb := ra (i);
-       end if;
-      rb := not rb;
-      res (i) := compute_sum (carry, rb, lb);
-      carry := compute_carry (carry, rb, lb);
-    end loop;
-    return res;
-  end "-";
-
-  function "-" (l : UNSIGNED; r : NATURAL) return UNSIGNED
-  is
-    subtype res_type is UNSIGNED (l'length - 1 downto 0);
-    alias la : res_type is l;
-     variable r1, r2 : NATURAL;
-     variable rd : nat1;
-    variable res : res_type;
-    variable lb, rb, carry : bit;
-  begin
-    if res'length < 0 then
-       return null_UNSIGNED;
-    end if;
-    carry := '1';
-    r1 := r;
-    for i in res'reverse_range loop
-       lb := la (i);
-
-       r2 := r1 / 2;
-       rd := r1 - 2 * r2;
-       r1 := r2;
-       rb := nat1_to_01 (rd);
-      rb := not rb;
-      res (i) := compute_sum (carry, rb, lb);
-      carry := compute_carry (carry, rb, lb);
-    end loop;
-    if r1 /= 0 then
-      assert NO_WARNING
-        report "NUMERIC_STD.""-"": vector is truncated"
-        severity warning;
-    end if;
-    return res;
-  end "-";
-
-  function "-" (l : NATURAL; r : UNSIGNED) return UNSIGNED
-  is
-    subtype res_type is UNSIGNED (r'length - 1 downto 0);
-    alias ra : res_type is r;
-     variable l1, l2 : NATURAL;
-     variable ld : nat1;
-    variable res : res_type;
-    variable lb, rb, carry : bit;
-  begin
-    if res'length < 0 then
-       return null_UNSIGNED;
-    end if;
-    carry := '1';
-    l1 := l;
-    for i in res'reverse_range loop
-       rb := ra (i);
-
-       l2 := l1 / 2;
-       ld := l1 - 2 * l2;
-       l1 := l2;
-       lb := nat1_to_01 (ld);
-      rb := not rb;
-      res (i) := compute_sum (carry, rb, lb);
-      carry := compute_carry (carry, rb, lb);
-    end loop;
-    if l1 /= 0 then
-      assert NO_WARNING
-        report "NUMERIC_STD.""-"": vector is truncated"
-        severity warning;
-    end if;
-    return res;
-  end "-";
-
-  function "-" (l : SIGNED; r : INTEGER) return SIGNED
-  is
-    subtype res_type is SIGNED (l'length - 1 downto 0);
-    alias la : res_type is l;
-     variable r1, r2 : INTEGER;
-     variable rd : nat1;
-     constant rmsb : nat1 := boolean'pos(r < 0);
-    variable res : res_type;
-    variable lb, rb, carry : bit;
-  begin
-    if res'length < 0 then
-       return null_SIGNED;
-    end if;
-    carry := '1';
-    r1 := r;
-    for i in res'reverse_range loop
-       lb := la (i);
-
-       r2 := r1 / 2;
-       if r1 < 0 then
-          rd := 2 * r2 - r1;
-          r1 := r2 - rd;
-        else
-          rd := r1 - 2 * r2;
-          r1 := r2;
-        end if;
-       rb := nat1_to_01 (rd);
-      rb := not rb;
-      res (i) := compute_sum (carry, rb, lb);
-      carry := compute_carry (carry, rb, lb);
-    end loop;
-    if r1 /= -rmsb then
-      assert NO_WARNING
-        report "NUMERIC_STD.""-"": vector is truncated"
-        severity warning;
-    end if;
-    return res;
-  end "-";
-
-  function "-" (l : INTEGER; r : SIGNED) return SIGNED
-  is
-    subtype res_type is SIGNED (r'length - 1 downto 0);
-    alias ra : res_type is r;
-     variable l1, l2 : INTEGER;
-     variable ld : nat1;
-     constant lmsb : nat1 := boolean'pos(l < 0);
-    variable res : res_type;
-    variable lb, rb, carry : bit;
-  begin
-    if res'length < 0 then
-       return null_SIGNED;
-    end if;
-    carry := '1';
-    l1 := l;
-    for i in res'reverse_range loop
-       rb := ra (i);
-
-       l2 := l1 / 2;
-       if l1 < 0 then
-          ld := 2 * l2 - l1;
-          l1 := l2 - ld;
-        else
-          ld := l1 - 2 * l2;
-          l1 := l2;
-        end if;
-       lb := nat1_to_01 (ld);
-      rb := not rb;
-      res (i) := compute_sum (carry, rb, lb);
-      carry := compute_carry (carry, rb, lb);
-    end loop;
-    if l1 /= -lmsb then
-      assert NO_WARNING
-        report "NUMERIC_STD.""-"": vector is truncated"
-        severity warning;
-    end if;
-    return res;
-  end "-";
-
-  function "*" (L, R : UNSIGNED) return UNSIGNED
-  is
-     alias la : UNSIGNED (L'Length - 1 downto 0) is l;
-     alias ra : UNSIGNED (R'Length - 1 downto 0) is r;
-     variable res : UNSIGNED (L'length + R'Length -1 downto 0) := (others => '0');
-     variable rb, lb, vb, carry : bit;
-  begin
-     if la'length = 0 or ra'length = 0 then
-        return null_UNSIGNED;
-     end if;
-     --  Shift and add L.
-     for i in natural range 0 to ra'left loop
-       rb := ra (i);
-       if rb = '1' then
-          --  Compute res := res + shift_left (l, i).
-          carry := '0';
-          for j in la'reverse_range loop
-            lb := la (j);
-            vb := res (i + j);
-            res (i + j) := compute_sum (carry, vb, lb);
-            carry := compute_carry (carry, vb, lb);
-          end loop;
-          --  Propagate carry.
-          for j in i + la'length to res'left loop
-             exit when carry = '0';
-             vb := res (j);
-             res (j) := carry xor vb;
-             carry := carry and vb;
-          end loop;
-       end if;
-     end loop;
-     return res;
-  end "*";
-
-  function "*" (L, R : SIGNED) return SIGNED
-  is
-     alias la : SIGNED (L'Length - 1 downto 0) is l;
-     alias ra : SIGNED (R'Length - 1 downto 0) is r;
-     variable res : SIGNED (L'length + R'Length -1 downto 0) := (others => '0');
-     variable rb, lb, vb, carry : bit;
-  begin
-     if la'length = 0 or ra'length = 0 then
-        return null_SIGNED;
-     end if;
-     --  Shift and add L.
-     for i in natural range 0 to ra'left - 1 loop
-       rb := ra (i);
-       if rb = '1' then
-          --  Compute res := res + shift_left (l, i).
-          carry := '0';
-          for j in la'reverse_range loop
-            lb := la (j);
-            vb := res (i + j);
-            res (i + j) := compute_sum (carry, vb, lb);
-            carry := compute_carry (carry, vb, lb);
-          end loop;
-          --  Sign extend and propagate carry.
-          lb := la (la'left);
-          for j in i + l'length to res'left loop
-             vb := res (j);
-             res (j) := compute_sum (carry, vb, lb);
-             carry := compute_carry (carry, vb, lb);
-          end loop;
-       end if;
-     end loop;
-     if ra (ra'left) = '1' then
-        --  R is a negative number.  It is considered as:
-        --   -2**n + (Rn-1 Rn-2 ... R0).
-        --  Compute res := res - 2**n * l.
-        carry := '1';
-        for i in la'reverse_range loop
-          vb := res (ra'length - 1 + i);
-          lb := not la (i);
-          res (ra'length - 1+ i) := compute_sum (carry, vb, lb);
-          carry := compute_carry (carry, vb, lb);
-        end loop;
-        vb := res (res'left);
-        lb := not la (la'left);
-        res (res'left) := compute_sum (carry, vb, lb);
-     end if;
-     return res;
-  end "*";
-
-  function "*" (L : UNSIGNED; R : NATURAL) return UNSIGNED
-  is
-     constant size : natural := l'length;
-  begin
-     if size = 0 then
-        return null_UNSIGNED;
-     end if;
-     return l * to_UNSIGNED (r, size);
-  end "*";
-
-  function "*" (L : SIGNED; R : INTEGER) return SIGNED
-  is
-     constant size : natural := l'length;
-  begin
-     if size = 0 then
-        return null_SIGNED;
-     end if;
-     return l * to_SIGNED (r, size);
-  end "*";
-
-  function "*" (L : NATURAL; R : UNSIGNED) return UNSIGNED
-  is
-     constant size : natural := r'length;
-  begin
-     if size = 0 then
-        return null_UNSIGNED;
-     end if;
-     return r * to_UNSIGNED (l, size);
-  end "*";
-
-  function "*" (L : INTEGER; R : SIGNED) return SIGNED
-  is
-     constant size : natural := r'length;
-  begin
-     if size = 0 then
-        return null_SIGNED;
-     end if;
-     return r * to_SIGNED (l, size);
-  end "*";
-
-  function has_0x (a : UNSIGNED) return bit
-  is
-     variable res : bit := '0';
-  begin
-     for i in a'range loop
-      res := res or a (i);
-    end loop;
-    return res;
-  end has_0x;
-
-    --  All index range are normalized (N downto 0).
-    --  NUM and QUOT have the same range.
-    --  DEM and REMAIN have the same range.
-    --  No 'X'.
-    procedure divmod (num, dem : UNSIGNED; quot, remain : out UNSIGNED)
-    is
-       variable reg : unsigned (dem'left + 1 downto 0) := (others => '0');
-       variable sub : unsigned (dem'range) := (others => '0');
-       variable carry, d : bit;
-    begin
-       for i in num'range loop
-          --  Shift
-          reg (reg'left downto 1) := reg (reg'left - 1 downto 0);
-          reg (0) := num (i);
-          --  Substract
-          carry := '1';
-          for j in dem'reverse_range loop
-             d := not dem (j);
-             sub (j) := compute_sum (carry, reg (j), d);
-             carry := compute_carry (carry, reg (j), d);
-          end loop;
-          carry := compute_carry (carry, reg (reg'left), '1');
-          --  Test
-          if carry = '0' then
-             --  Greater than
-             quot (i) := '0';
-          else
-             quot (i) := '1';
-             reg (reg'left) := '0';
-             reg (sub'range) := sub;
-          end if;
-        end loop;
-        remain := reg (dem'range);
-    end divmod;
-    
-  function size_unsigned (n : natural) return natural
-  is
-     --  At least one bit (even for 0).
-     variable res : natural := 1;
-     variable n1 : natural := n;
-  begin
-     while n1 > 1 loop
-        res := res + 1;
-        n1 := n1 / 2;
-     end loop;
-     return res;
-  end size_unsigned;
-
-  function size_signed (n : integer) return natural
-  is
-     variable res : natural := 1;
-     variable n1 : natural;
-  begin
-     if n >= 0 then
-        n1 := n;
-     else
-        -- Use /N = -X -1 = -(X + 1)  (No overflow).
-        n1 := -(n + 1);
-     end if;
-     while n1 /= 0 loop
-        res := res + 1;
-        n1 := n1 / 2;
-     end loop;
-     return res;
-  end size_signed;
-
-  function "/" (L, R : UNSIGNED) return UNSIGNED
-  is
-     subtype l_type is UNSIGNED (L'length - 1 downto 0);
-     subtype r_type is UNSIGNED (R'length - 1 downto 0);
-     alias la : l_type is l;
-     alias ra : r_type is r;
-     variable quot : l_type;
-     variable rema : r_type;
-     variable r0 : bit := has_0x (r);
-  begin
-     if la'length = 0 or ra'length = 0 then
-        return null_unsigned;
-     end if;
-     assert r0 /= '0'
-        report "NUMERIC_STD.""/"": division by 0"
-        severity error;
-     divmod (la, ra, quot, rema);
-     return quot;
-  end "/";
-
-  function "/" (L : UNSIGNED; R : NATURAL) return UNSIGNED
-  is
-     constant r_size : natural := size_unsigned (r);
-  begin
-     if l'length = 0 then
-        return null_unsigned;
-     end if;
-     return l / to_unsigned (r, r_size);
-  end "/";
-
-  function "/" (L : NATURAL; R : UNSIGNED) return UNSIGNED
-  is
-     constant l_size : natural := size_unsigned (l);
-  begin
-     if r'length = 0 then
-        return null_unsigned;
-     end if;
-     return resize (to_unsigned (l, l_size) / r, r'length);
-  end "/";
-
-  function "rem" (L, R : UNSIGNED) return UNSIGNED
-  is
-     subtype l_type is UNSIGNED (L'length - 1 downto 0);
-     subtype r_type is UNSIGNED (R'length - 1 downto 0);
-     alias la : l_type is l;
-     alias ra : r_type is r;
-     variable quot : l_type;
-     variable rema : r_type;
-     variable r0 : bit := has_0x (r);
-  begin
-     if la'length = 0 or ra'length = 0 then
-        return null_unsigned;
-     end if;
-     assert r0 /= '0'
-        report "NUMERIC_STD.""rem"": division by 0"
-        severity error;
-     divmod (la, ra, quot, rema);
-     return rema;
-  end "rem";
-
-  function "rem" (L : UNSIGNED; R : NATURAL) return UNSIGNED
-  is
-     constant r_size : natural := size_unsigned (r);
-  begin
-     if l'length = 0 then
-        return null_unsigned;
-     end if;
-     return resize (l rem to_unsigned (r, r_size), l'length);
-  end "rem";
-
-  function "rem" (L : NATURAL; R : UNSIGNED) return UNSIGNED
-  is
-     constant l_size : natural := size_unsigned (l);
-  begin
-     if r'length = 0 then
-        return null_unsigned;
-     end if;
-     return to_unsigned (l, l_size) rem r;
-  end "rem";
-
-  function "mod" (L, R : UNSIGNED) return UNSIGNED
-  is
-     subtype l_type is UNSIGNED (L'length - 1 downto 0);
-     subtype r_type is UNSIGNED (R'length - 1 downto 0);
-     alias la : l_type is l;
-     alias ra : r_type is r;
-     variable quot : l_type;
-     variable rema : r_type;
-     variable r0 : bit := has_0x (r);
-  begin
-     if la'length = 0 or ra'length = 0 then
-        return null_unsigned;
-     end if;
-     assert r0 /= '0'
-        report "NUMERIC_STD.""mod"": division by 0"
-        severity error;
-     divmod (la, ra, quot, rema);
-     return rema;
-  end "mod";
-
-  function "mod" (L : UNSIGNED; R : NATURAL) return UNSIGNED
-  is
-     constant r_size : natural := size_unsigned (r);
-  begin
-     if l'length = 0 then
-        return null_unsigned;
-     end if;
-     return resize (l mod to_unsigned (r, r_size), l'length);
-  end "mod";
-
-  function "mod" (L : NATURAL; R : UNSIGNED) return UNSIGNED
-  is
-     constant l_size : natural := size_unsigned (l);
-  begin
-     if r'length = 0 then
-        return null_unsigned;
-     end if;
-     return to_unsigned (l, l_size) mod r;
-  end "mod";
-
-  function has_0x (a : SIGNED) return bit
-  is
-     variable res : bit := '0';
-  begin
-     for i in a'range loop
-      res := res or a (i);
-    end loop;
-    return res;
-  end has_0x;
-
-  function "-" (ARG : SIGNED) return SIGNED
-  is
-     subtype arg_type is SIGNED (ARG'length - 1 downto 0);
-     alias arga : arg_type is arg;
-     variable res : arg_type;
-     variable carry, a : bit;
-  begin
-     if arga'length = 0 then
-        return null_signed;
-     end if;
-     carry := '1';
-     for i in arga'reverse_range loop
-       a := not arga (i);
-       res (i) := carry xor a;
-       carry := carry and a;
-     end loop;
-     return res;
-  end "-";
-
-  function "abs" (ARG : SIGNED) return SIGNED
-  is
-     subtype arg_type is SIGNED (ARG'length - 1 downto 0);
-     alias arga : arg_type is arg;
-     variable res : arg_type;
-     variable carry, a : bit;
-  begin
-     if arga'length = 0 then
-        return null_signed;
-     end if;
-     if arga (arga'left) = '0' then
-        return arga;
-     end if;
-     carry := '1';
-     for i in arga'reverse_range loop
-       a := not arga (i);
-       res (i) := carry xor a;
-       carry := carry and a;
-     end loop;
-     return res;
-  end "abs";
-
-  function "/" (L, R : SIGNED) return SIGNED
-  is
-     subtype l_type is SIGNED (L'length - 1 downto 0);
-     subtype r_type is SIGNED (R'length - 1 downto 0);
-     alias la : l_type is l;
-     alias ra : r_type is r;
-     subtype l_utype is UNSIGNED (l_type'range);
-     subtype r_utype is UNSIGNED (r_type'range);
-     variable lu : l_utype;
-     variable ru : r_utype;
-     variable quot : l_utype;
-     variable rema : r_utype;
-     variable r0 : bit := has_0x (r);
-  begin
-     if la'length = 0 or ra'length = 0 then
-        return null_signed;
-     end if;
-     assert r0 /= '0'
-        report "NUMERIC_STD.""/"": division by 0"
-        severity error;
-     if la (la'left) = '1' then
-        lu := unsigned (-la);
-     else
-        lu := unsigned (la);
-     end if;
-     if ra (ra'left) = '1' then
-        ru := unsigned (-ra);
-     else
-        ru := unsigned (ra);
-     end if;
-     divmod (lu, ru, quot, rema);
-     if (ra (ra'left) xor la (la'left)) = '1' then
-       return -signed (quot);
-     else
-       return signed (quot);
-     end if;
-  end "/";
-
-  function "/" (L : SIGNED; R : INTEGER) return SIGNED
-  is
-     constant r_size : natural := size_signed (r);
-  begin
-     if l'length = 0 then
-        return null_signed;
-     end if;
-     return l / to_signed (r, r_size);
-  end "/";
-
-  function "/" (L : INTEGER; R : SIGNED) return SIGNED
-  is
-     constant l_size : natural := size_signed (l);
-  begin
-     if r'length = 0 then
-        return null_signed;
-     end if;
-     return resize (to_signed (l, max (l_size, r'length)) / r, r'length);
-  end "/";
-
-  function "rem" (L, R : SIGNED) return SIGNED
-  is
-     subtype l_type is SIGNED (L'length - 1 downto 0);
-     subtype r_type is SIGNED (R'length - 1 downto 0);
-     alias la : l_type is l;
-     alias ra : r_type is r;
-     subtype l_utype is UNSIGNED (l_type'range);
-     subtype r_utype is UNSIGNED (r_type'range);
-     variable lu : l_utype;
-     variable ru : r_utype;
-     variable quot : l_utype;
-     variable rema : r_utype;
-     variable r0 : bit := has_0x (r);
-  begin
-     if la'length = 0 or ra'length = 0 then
-        return null_signed;
-     end if;
-     assert r0 /= '0'
-        report "NUMERIC_STD.""rem"": division by 0"
-        severity error;
-     if la (la'left) = '1' then
-        lu := unsigned (-la);
-     else
-        lu := unsigned (la);
-     end if;
-     if ra (ra'left) = '1' then
-        ru := unsigned (-ra);
-     else
-        ru := unsigned (ra);
-     end if;
-     divmod (lu, ru, quot, rema);
-     --  Result of rem has the sign of the dividend.
-     if la (la'left) = '1' then
-       return -signed (rema);
-     else
-       return signed (rema);
-     end if;
-  end "rem";
-
-  function "rem" (L : SIGNED; R : INTEGER) return SIGNED
-  is
-     constant r_size : natural := size_signed (r);
-  begin
-     if l'length = 0 then
-        return null_signed;
-     end if;
-     return resize (l rem to_signed (r, r_size), l'length);
-  end "rem";
-
-  function "rem" (L : INTEGER; R : SIGNED) return SIGNED
-  is
-     constant l_size : natural := size_signed (l);
-  begin
-     if r'length = 0 then
-        return null_signed;
-     end if;
-     return to_signed (l, l_size) rem r;
-  end "rem";
-
-  function "mod" (L, R : SIGNED) return SIGNED
-  is
-     subtype l_type is SIGNED (L'length - 1 downto 0);
-     subtype r_type is SIGNED (R'length - 1 downto 0);
-     alias la : l_type is l;
-     alias ra : r_type is r;
-     subtype l_utype is UNSIGNED (l_type'range);
-     subtype r_utype is UNSIGNED (r_type'range);
-     variable lu : l_utype;
-     variable ru : r_utype;
-     variable quot : l_utype;
-     variable rema : r_utype;
-     variable r0 : bit := has_0x (r);
-  begin
-     if la'length = 0 or ra'length = 0 then
-        return null_signed;
-     end if;
-     assert r0 /= '0'
-        report "NUMERIC_STD.""mod"": division by 0"
-        severity error;
-     if la (la'left) = '1' then
-        lu := unsigned (-la);
-     else
-        lu := unsigned (la);
-     end if;
-     if ra (ra'left) = '1' then
-        ru := unsigned (-ra);
-     else
-        ru := unsigned (ra);
-     end if;
-     divmod (lu, ru, quot, rema);
-     --  Result of mod has the sign of the divisor.
-     if rema = r_utype'(others => '0') then
-        --  If the remainder is 0, then the modulus is 0.
-        return signed (rema);
-     else
-        if ra (ra'left) = '1' then
-           if la (la'left) = '1' then
-              return -signed (rema);
-           else
-              return ra + signed (rema);
-           end if;
-        else
-           if la (la'left) = '1' then
-              return ra - signed (rema);
-           else
-              return signed (rema);
-           end if;
-        end if;
-     end if;
-  end "mod";
-
-  function "mod" (L : SIGNED; R : INTEGER) return SIGNED
-  is
-     constant r_size : natural := size_signed (r);
-  begin
-     if l'length = 0 then
-        return null_signed;
-     end if;
-     return resize (l mod to_signed (r, r_size), l'length);
-  end "mod";
-
-  function "mod" (L : INTEGER; R : SIGNED) return SIGNED
-  is
-     constant l_size : natural := size_signed (l);
-  begin
-     if r'length = 0 then
-        return null_signed;
-     end if;
-     return to_signed (l, l_size) mod r;
-  end "mod";
-
-
-  function resize (ARG : UNSIGNED; NEW_SIZE: natural) return UNSIGNED
-  is
-     alias arg1 : UNSIGNED (ARG'length - 1 downto 0) is arg;
-     variable res : UNSIGNED (new_size - 1 downto 0) := (others => '0');
-  begin
-     if new_size = 0 then
-        return null_UNSIGNED;
-     end if;
-     if arg1'length = 0 then
-        return res;
-     end if;
-     if arg1'length > new_size then
-        --  Reduction.
-        res := arg1 (res'range);
-     else
-        --  Expansion
-        res (arg1'range) := arg1;
-    end if;
-    return res;
-  end resize;
-
-  function resize (ARG : SIGNED; NEW_SIZE: natural) return SIGNED
-  is
-     alias arg1 : SIGNED (ARG'length - 1 downto 0) is arg;
-     variable res : SIGNED (new_size - 1 downto 0) := (others => '0');
-  begin
-     if new_size = 0 then
-        return null_SIGNED;
-     end if;
-     if arg1'length = 0 then
-        return res;
-     end if;
-     if arg1'length > new_size then
-        --  Reduction.
-        res (res'left) := arg1 (arg1'left);
-        res (res'left - 1 downto 0) := arg1 (res'left - 1 downto 0);
-     else
-        --  Expansion
-        res (arg1'range) := arg1;
-        res (res'left downto arg1'length) := (others => arg1 (arg1'left));
-    end if;
-    return res;
-  end resize;
-
-  function "not" (l : UNSIGNED) return UNSIGNED
-  is
-    subtype res_type is UNSIGNED (l'length - 1 downto 0);
-    alias la : res_type is l;
-    variable res : res_type;
-  begin
-    for I in res_type'range loop
-      res (I) := not la (I);
-    end loop;
-    return res;
-  end "not";
-
-  function "not" (l : SIGNED) return SIGNED
-  is
-    subtype res_type is SIGNED (l'length - 1 downto 0);
-    alias la : res_type is l;
-    variable res : res_type;
-  begin
-    for I in res_type'range loop
-      res (I) := not la (I);
-    end loop;
-    return res;
-  end "not";
-
-  function "and" (l, r : UNSIGNED) return UNSIGNED
-  is
-    subtype res_type is UNSIGNED (l'length - 1 downto 0);
-    alias la : res_type is l;
-    alias ra : UNSIGNED (r'length - 1 downto 0) is r;
-    variable res : res_type;
-  begin
-    if la'left /= ra'left then
-      assert false
-        report "NUMERIC_STD.""and"": arguments are not of the same length"
-        severity failure;
-      res := (others => '0');
-    else
-      for I in res_type'range loop
-        res (I) := la (I) and ra (I);
-      end loop;
-    end if;
-    return res;
-  end "and";
-
-  function "and" (l, r : SIGNED) return SIGNED
-  is
-    subtype res_type is SIGNED (l'length - 1 downto 0);
-    alias la : res_type is l;
-    alias ra : SIGNED (r'length - 1 downto 0) is r;
-    variable res : res_type;
-  begin
-    if la'left /= ra'left then
-      assert false
-        report "NUMERIC_STD.""and"": arguments are not of the same length"
-        severity failure;
-      res := (others => '0');
-    else
-      for I in res_type'range loop
-        res (I) := la (I) and ra (I);
-      end loop;
-    end if;
-    return res;
-  end "and";
-
-  function "nand" (l, r : UNSIGNED) return UNSIGNED
-  is
-    subtype res_type is UNSIGNED (l'length - 1 downto 0);
-    alias la : res_type is l;
-    alias ra : UNSIGNED (r'length - 1 downto 0) is r;
-    variable res : res_type;
-  begin
-    if la'left /= ra'left then
-      assert false
-        report "NUMERIC_STD.""nand"": arguments are not of the same length"
-        severity failure;
-      res := (others => '0');
-    else
-      for I in res_type'range loop
-        res (I) := la (I) nand ra (I);
-      end loop;
-    end if;
-    return res;
-  end "nand";
-
-  function "nand" (l, r : SIGNED) return SIGNED
-  is
-    subtype res_type is SIGNED (l'length - 1 downto 0);
-    alias la : res_type is l;
-    alias ra : SIGNED (r'length - 1 downto 0) is r;
-    variable res : res_type;
-  begin
-    if la'left /= ra'left then
-      assert false
-        report "NUMERIC_STD.""nand"": arguments are not of the same length"
-        severity failure;
-      res := (others => '0');
-    else
-      for I in res_type'range loop
-        res (I) := la (I) nand ra (I);
-      end loop;
-    end if;
-    return res;
-  end "nand";
-
-  function "or" (l, r : UNSIGNED) return UNSIGNED
-  is
-    subtype res_type is UNSIGNED (l'length - 1 downto 0);
-    alias la : res_type is l;
-    alias ra : UNSIGNED (r'length - 1 downto 0) is r;
-    variable res : res_type;
-  begin
-    if la'left /= ra'left then
-      assert false
-        report "NUMERIC_STD.""or"": arguments are not of the same length"
-        severity failure;
-      res := (others => '0');
-    else
-      for I in res_type'range loop
-        res (I) := la (I) or ra (I);
-      end loop;
-    end if;
-    return res;
-  end "or";
-
-  function "or" (l, r : SIGNED) return SIGNED
-  is
-    subtype res_type is SIGNED (l'length - 1 downto 0);
-    alias la : res_type is l;
-    alias ra : SIGNED (r'length - 1 downto 0) is r;
-    variable res : res_type;
-  begin
-    if la'left /= ra'left then
-      assert false
-        report "NUMERIC_STD.""or"": arguments are not of the same length"
-        severity failure;
-      res := (others => '0');
-    else
-      for I in res_type'range loop
-        res (I) := la (I) or ra (I);
-      end loop;
-    end if;
-    return res;
-  end "or";
-
-  function "nor" (l, r : UNSIGNED) return UNSIGNED
-  is
-    subtype res_type is UNSIGNED (l'length - 1 downto 0);
-    alias la : res_type is l;
-    alias ra : UNSIGNED (r'length - 1 downto 0) is r;
-    variable res : res_type;
-  begin
-    if la'left /= ra'left then
-      assert false
-        report "NUMERIC_STD.""nor"": arguments are not of the same length"
-        severity failure;
-      res := (others => '0');
-    else
-      for I in res_type'range loop
-        res (I) := la (I) nor ra (I);
-      end loop;
-    end if;
-    return res;
-  end "nor";
-
-  function "nor" (l, r : SIGNED) return SIGNED
-  is
-    subtype res_type is SIGNED (l'length - 1 downto 0);
-    alias la : res_type is l;
-    alias ra : SIGNED (r'length - 1 downto 0) is r;
-    variable res : res_type;
-  begin
-    if la'left /= ra'left then
-      assert false
-        report "NUMERIC_STD.""nor"": arguments are not of the same length"
-        severity failure;
-      res := (others => '0');
-    else
-      for I in res_type'range loop
-        res (I) := la (I) nor ra (I);
-      end loop;
-    end if;
-    return res;
-  end "nor";
-
-  function "xor" (l, r : UNSIGNED) return UNSIGNED
-  is
-    subtype res_type is UNSIGNED (l'length - 1 downto 0);
-    alias la : res_type is l;
-    alias ra : UNSIGNED (r'length - 1 downto 0) is r;
-    variable res : res_type;
-  begin
-    if la'left /= ra'left then
-      assert false
-        report "NUMERIC_STD.""xor"": arguments are not of the same length"
-        severity failure;
-      res := (others => '0');
-    else
-      for I in res_type'range loop
-        res (I) := la (I) xor ra (I);
-      end loop;
-    end if;
-    return res;
-  end "xor";
-
-  function "xor" (l, r : SIGNED) return SIGNED
-  is
-    subtype res_type is SIGNED (l'length - 1 downto 0);
-    alias la : res_type is l;
-    alias ra : SIGNED (r'length - 1 downto 0) is r;
-    variable res : res_type;
-  begin
-    if la'left /= ra'left then
-      assert false
-        report "NUMERIC_STD.""xor"": arguments are not of the same length"
-        severity failure;
-      res := (others => '0');
-    else
-      for I in res_type'range loop
-        res (I) := la (I) xor ra (I);
-      end loop;
-    end if;
-    return res;
-  end "xor";
-
-  function ucompare (l, r : UNSIGNED) return compare_type
-  is
-     constant sz : integer := MAX (l'length, r'length) - 1;
-     alias la : UNSIGNED (l'length - 1 downto 0) is l;
-     alias ra : UNSIGNED (r'length - 1 downto 0) is r;
-     variable lb, rb : bit;
-     variable res : compare_type;
-  begin
-     res := compare_eq;
-    for i in 0 to sz loop
-       if i > la'left then
-          lb := '0';
-       else
-          lb := la (i);
-       end if;
-       if i > ra'left then
-          rb := '0';
-       else
-          rb := ra (i);
-       end if;
-       if lb = '1' and rb = '0' then
-         res := compare_gt;
-       elsif lb = '0' and rb = '1' then
-         res := compare_lt;
-       end if;
-     end loop;
-
-     return res;
-  end ucompare;
-
-  function scompare (l, r : SIGNED) return compare_type
-  is
-     constant sz : integer := MAX (l'length, r'length) - 1;
-     alias la : SIGNED (l'length - 1 downto 0) is l;
-     alias ra : SIGNED (r'length - 1 downto 0) is r;
-     variable lb, rb : bit;
-     variable res : compare_type;
-  begin
-     --  Consider sign bit as S * -(2**N).
-     lb := la (la'left);
-     rb := ra (ra'left);
-     if lb = '1' and rb = '0' then
-        return compare_lt;
-     elsif lb = '0' and rb = '1' then
-        return compare_gt;
-     else
-        res := compare_eq;
-     end if;
-     for i in 0 to sz - 1 loop
-       if i > la'left then
-          lb := l (l'left);
-       else
-          lb := la (i);
-       end if;
-       if i > ra'left then
-          rb := r (r'left);
-       else
-          rb := ra (i);
-       end if;
-       if lb = '1' and rb = '0' then
-         res := compare_gt;
-       elsif lb = '0' and rb = '1' then
-         res := compare_lt;
-       end if;
-     end loop;
-
-     return res;
-  end scompare;
-
-  function ucompare (l : UNSIGNED; r : NATURAL) return compare_type
-  is
-    subtype res_type is UNSIGNED (l'length - 1 downto 0);
-    alias la : res_type is l;
-     variable r1, r2 : NATURAL;
-     variable rd : nat1;
-    variable lb, rb : bit;
-    variable res : compare_type;
-  begin
-    res := compare_eq;
-    r1 := r;
-    for i in la'reverse_range loop
-       lb := la (i);
-       r2 := r1 / 2;
-       rd := r1 - 2 * r2;
-       r1 := r2;
-       rb := nat1_to_01 (rd);
-       if lb = '1' and rb = '0' then
-         res := compare_gt;
-       elsif lb = '0' and rb = '1' then
-         res := compare_lt;
-       end if;
-    end loop;
-    if r1 /= 0 then
-       res := compare_lt;
-    end if;
-    return res;
-  end ucompare;
-
-  function scompare (l : SIGNED; r : INTEGER) return compare_type
-  is
-    subtype res_type is SIGNED (l'length - 1 downto 0);
-    alias la : res_type is l;
-     variable r1, r2 : INTEGER;
-     variable rd : nat1;
-     constant rmsb : nat1 := boolean'pos(r < 0);
-    variable lb, rb : bit;
-    variable res : compare_type;
-  begin
-    res := compare_eq;
-    r1 := r;
-    for i in la'reverse_range loop
-       lb := la (i);
-       r2 := r1 / 2;
-       if r1 < 0 then
-          rd := 2 * r2 - r1;
-          r1 := r2 - rd;
-        else
-          rd := r1 - 2 * r2;
-          r1 := r2;
-        end if;
-       rb := nat1_to_01 (rd);
-       if lb = '1' and rb = '0' then
-         res := compare_gt;
-       elsif lb = '0' and rb = '1' then
-         res := compare_lt;
-       end if;
-    end loop;
-    if l (l'left) = '1' then
-      if r >= 0 then
-         res := compare_lt;
-      end if;
-    else
-      if r < 0 then
-         res := compare_gt;
-      end if;
-    end if;
-    return res;
-  end scompare;
-
-  function "=" (l, r : UNSIGNED) return boolean
-  is
-     variable res : compare_type;
-  begin
-     if l'length = 0 or r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := ucompare (l, r);
-     return res = compare_eq;
-  end "=";
-
-  function "=" (l, r : SIGNED) return boolean
-  is
-     variable res : compare_type;
-  begin
-     if l'length = 0 or r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := scompare (l, r);
-     return res = compare_eq;
-  end "=";
-
-  function "=" (l : UNSIGNED; r : NATURAL) return boolean
-  is
-     subtype res_type is UNSIGNED (l'length - 1 downto 0);
-     alias la : res_type is l;
-     variable r1, r2 : NATURAL;
-     variable rd : nat1;
-     variable res : compare_type;
-  begin
-     if l'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := ucompare (l, r);
-     return res = compare_eq;
-  end "=";
-
-  function "=" (l : NATURAL; r : UNSIGNED) return boolean
-  is
-     subtype res_type is UNSIGNED (r'length - 1 downto 0);
-     alias ra : res_type is r;
-     variable l1, l2 : NATURAL;
-     variable ld : nat1;
-     variable res : compare_type;
-  begin
-     if r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := ucompare (r, l);
-     return compare_eq = res;
-  end "=";
-
-  function "=" (l : SIGNED; r : INTEGER) return boolean
-  is
-     subtype res_type is SIGNED (l'length - 1 downto 0);
-     alias la : res_type is l;
-     variable r1, r2 : INTEGER;
-     variable rd : nat1;
-     constant rmsb : nat1 := boolean'pos(r < 0);
-     variable res : compare_type;
-  begin
-     if l'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := scompare (l, r);
-     return res = compare_eq;
-  end "=";
-
-  function "=" (l : INTEGER; r : SIGNED) return boolean
-  is
-     subtype res_type is SIGNED (r'length - 1 downto 0);
-     alias ra : res_type is r;
-     variable l1, l2 : INTEGER;
-     variable ld : nat1;
-     constant lmsb : nat1 := boolean'pos(l < 0);
-     variable res : compare_type;
-  begin
-     if r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := scompare (r, l);
-     return compare_eq = res;
-  end "=";
-
-  function "/=" (l, r : UNSIGNED) return boolean
-  is
-     variable res : compare_type;
-  begin
-     if l'length = 0 or r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""/="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := ucompare (l, r);
-     return res /= compare_eq;
-  end "/=";
-
-  function "/=" (l, r : SIGNED) return boolean
-  is
-     variable res : compare_type;
-  begin
-     if l'length = 0 or r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""/="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := scompare (l, r);
-     return res /= compare_eq;
-  end "/=";
-
-  function "/=" (l : UNSIGNED; r : NATURAL) return boolean
-  is
-     subtype res_type is UNSIGNED (l'length - 1 downto 0);
-     alias la : res_type is l;
-     variable r1, r2 : NATURAL;
-     variable rd : nat1;
-     variable res : compare_type;
-  begin
-     if l'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""/="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := ucompare (l, r);
-     return res /= compare_eq;
-  end "/=";
-
-  function "/=" (l : NATURAL; r : UNSIGNED) return boolean
-  is
-     subtype res_type is UNSIGNED (r'length - 1 downto 0);
-     alias ra : res_type is r;
-     variable l1, l2 : NATURAL;
-     variable ld : nat1;
-     variable res : compare_type;
-  begin
-     if r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""/="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := ucompare (r, l);
-     return compare_eq /= res;
-  end "/=";
-
-  function "/=" (l : SIGNED; r : INTEGER) return boolean
-  is
-     subtype res_type is SIGNED (l'length - 1 downto 0);
-     alias la : res_type is l;
-     variable r1, r2 : INTEGER;
-     variable rd : nat1;
-     constant rmsb : nat1 := boolean'pos(r < 0);
-     variable res : compare_type;
-  begin
-     if l'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""/="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := scompare (l, r);
-     return res /= compare_eq;
-  end "/=";
-
-  function "/=" (l : INTEGER; r : SIGNED) return boolean
-  is
-     subtype res_type is SIGNED (r'length - 1 downto 0);
-     alias ra : res_type is r;
-     variable l1, l2 : INTEGER;
-     variable ld : nat1;
-     constant lmsb : nat1 := boolean'pos(l < 0);
-     variable res : compare_type;
-  begin
-     if r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""/="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := scompare (r, l);
-     return compare_eq /= res;
-  end "/=";
-
-  function ">" (l, r : UNSIGNED) return boolean
-  is
-     variable res : compare_type;
-  begin
-     if l'length = 0 or r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD."">"": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := ucompare (l, r);
-     return res > compare_eq;
-  end ">";
-
-  function ">" (l, r : SIGNED) return boolean
-  is
-     variable res : compare_type;
-  begin
-     if l'length = 0 or r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD."">"": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := scompare (l, r);
-     return res > compare_eq;
-  end ">";
-
-  function ">" (l : UNSIGNED; r : NATURAL) return boolean
-  is
-     subtype res_type is UNSIGNED (l'length - 1 downto 0);
-     alias la : res_type is l;
-     variable r1, r2 : NATURAL;
-     variable rd : nat1;
-     variable res : compare_type;
-  begin
-     if l'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD."">"": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := ucompare (l, r);
-     return res > compare_eq;
-  end ">";
-
-  function ">" (l : NATURAL; r : UNSIGNED) return boolean
-  is
-     subtype res_type is UNSIGNED (r'length - 1 downto 0);
-     alias ra : res_type is r;
-     variable l1, l2 : NATURAL;
-     variable ld : nat1;
-     variable res : compare_type;
-  begin
-     if r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD."">"": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := ucompare (r, l);
-     return compare_eq > res;
-  end ">";
-
-  function ">" (l : SIGNED; r : INTEGER) return boolean
-  is
-     subtype res_type is SIGNED (l'length - 1 downto 0);
-     alias la : res_type is l;
-     variable r1, r2 : INTEGER;
-     variable rd : nat1;
-     constant rmsb : nat1 := boolean'pos(r < 0);
-     variable res : compare_type;
-  begin
-     if l'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD."">"": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := scompare (l, r);
-     return res > compare_eq;
-  end ">";
-
-  function ">" (l : INTEGER; r : SIGNED) return boolean
-  is
-     subtype res_type is SIGNED (r'length - 1 downto 0);
-     alias ra : res_type is r;
-     variable l1, l2 : INTEGER;
-     variable ld : nat1;
-     constant lmsb : nat1 := boolean'pos(l < 0);
-     variable res : compare_type;
-  begin
-     if r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD."">"": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := scompare (r, l);
-     return compare_eq > res;
-  end ">";
-
-  function ">=" (l, r : UNSIGNED) return boolean
-  is
-     variable res : compare_type;
-  begin
-     if l'length = 0 or r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD."">="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := ucompare (l, r);
-     return res >= compare_eq;
-  end ">=";
-
-  function ">=" (l, r : SIGNED) return boolean
-  is
-     variable res : compare_type;
-  begin
-     if l'length = 0 or r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD."">="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := scompare (l, r);
-     return res >= compare_eq;
-  end ">=";
-
-  function ">=" (l : UNSIGNED; r : NATURAL) return boolean
-  is
-     subtype res_type is UNSIGNED (l'length - 1 downto 0);
-     alias la : res_type is l;
-     variable r1, r2 : NATURAL;
-     variable rd : nat1;
-     variable res : compare_type;
-  begin
-     if l'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD."">="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := ucompare (l, r);
-     return res >= compare_eq;
-  end ">=";
-
-  function ">=" (l : NATURAL; r : UNSIGNED) return boolean
-  is
-     subtype res_type is UNSIGNED (r'length - 1 downto 0);
-     alias ra : res_type is r;
-     variable l1, l2 : NATURAL;
-     variable ld : nat1;
-     variable res : compare_type;
-  begin
-     if r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD."">="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := ucompare (r, l);
-     return compare_eq >= res;
-  end ">=";
-
-  function ">=" (l : SIGNED; r : INTEGER) return boolean
-  is
-     subtype res_type is SIGNED (l'length - 1 downto 0);
-     alias la : res_type is l;
-     variable r1, r2 : INTEGER;
-     variable rd : nat1;
-     constant rmsb : nat1 := boolean'pos(r < 0);
-     variable res : compare_type;
-  begin
-     if l'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD."">="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := scompare (l, r);
-     return res >= compare_eq;
-  end ">=";
-
-  function ">=" (l : INTEGER; r : SIGNED) return boolean
-  is
-     subtype res_type is SIGNED (r'length - 1 downto 0);
-     alias ra : res_type is r;
-     variable l1, l2 : INTEGER;
-     variable ld : nat1;
-     constant lmsb : nat1 := boolean'pos(l < 0);
-     variable res : compare_type;
-  begin
-     if r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD."">="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := scompare (r, l);
-     return compare_eq >= res;
-  end ">=";
-
-  function "<" (l, r : UNSIGNED) return boolean
-  is
-     variable res : compare_type;
-  begin
-     if l'length = 0 or r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""<"": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := ucompare (l, r);
-     return res < compare_eq;
-  end "<";
-
-  function "<" (l, r : SIGNED) return boolean
-  is
-     variable res : compare_type;
-  begin
-     if l'length = 0 or r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""<"": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := scompare (l, r);
-     return res < compare_eq;
-  end "<";
-
-  function "<" (l : UNSIGNED; r : NATURAL) return boolean
-  is
-     subtype res_type is UNSIGNED (l'length - 1 downto 0);
-     alias la : res_type is l;
-     variable r1, r2 : NATURAL;
-     variable rd : nat1;
-     variable res : compare_type;
-  begin
-     if l'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""<"": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := ucompare (l, r);
-     return res < compare_eq;
-  end "<";
-
-  function "<" (l : NATURAL; r : UNSIGNED) return boolean
-  is
-     subtype res_type is UNSIGNED (r'length - 1 downto 0);
-     alias ra : res_type is r;
-     variable l1, l2 : NATURAL;
-     variable ld : nat1;
-     variable res : compare_type;
-  begin
-     if r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""<"": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := ucompare (r, l);
-     return compare_eq < res;
-  end "<";
-
-  function "<" (l : SIGNED; r : INTEGER) return boolean
-  is
-     subtype res_type is SIGNED (l'length - 1 downto 0);
-     alias la : res_type is l;
-     variable r1, r2 : INTEGER;
-     variable rd : nat1;
-     constant rmsb : nat1 := boolean'pos(r < 0);
-     variable res : compare_type;
-  begin
-     if l'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""<"": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := scompare (l, r);
-     return res < compare_eq;
-  end "<";
-
-  function "<" (l : INTEGER; r : SIGNED) return boolean
-  is
-     subtype res_type is SIGNED (r'length - 1 downto 0);
-     alias ra : res_type is r;
-     variable l1, l2 : INTEGER;
-     variable ld : nat1;
-     constant lmsb : nat1 := boolean'pos(l < 0);
-     variable res : compare_type;
-  begin
-     if r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""<"": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := scompare (r, l);
-     return compare_eq < res;
-  end "<";
-
-  function "<=" (l, r : UNSIGNED) return boolean
-  is
-     variable res : compare_type;
-  begin
-     if l'length = 0 or r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""<="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := ucompare (l, r);
-     return res <= compare_eq;
-  end "<=";
-
-  function "<=" (l, r : SIGNED) return boolean
-  is
-     variable res : compare_type;
-  begin
-     if l'length = 0 or r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""<="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := scompare (l, r);
-     return res <= compare_eq;
-  end "<=";
-
-  function "<=" (l : UNSIGNED; r : NATURAL) return boolean
-  is
-     subtype res_type is UNSIGNED (l'length - 1 downto 0);
-     alias la : res_type is l;
-     variable r1, r2 : NATURAL;
-     variable rd : nat1;
-     variable res : compare_type;
-  begin
-     if l'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""<="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := ucompare (l, r);
-     return res <= compare_eq;
-  end "<=";
-
-  function "<=" (l : NATURAL; r : UNSIGNED) return boolean
-  is
-     subtype res_type is UNSIGNED (r'length - 1 downto 0);
-     alias ra : res_type is r;
-     variable l1, l2 : NATURAL;
-     variable ld : nat1;
-     variable res : compare_type;
-  begin
-     if r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""<="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := ucompare (r, l);
-     return compare_eq <= res;
-  end "<=";
-
-  function "<=" (l : SIGNED; r : INTEGER) return boolean
-  is
-     subtype res_type is SIGNED (l'length - 1 downto 0);
-     alias la : res_type is l;
-     variable r1, r2 : INTEGER;
-     variable rd : nat1;
-     constant rmsb : nat1 := boolean'pos(r < 0);
-     variable res : compare_type;
-  begin
-     if l'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""<="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := scompare (l, r);
-     return res <= compare_eq;
-  end "<=";
-
-  function "<=" (l : INTEGER; r : SIGNED) return boolean
-  is
-     subtype res_type is SIGNED (r'length - 1 downto 0);
-     alias ra : res_type is r;
-     variable l1, l2 : INTEGER;
-     variable ld : nat1;
-     constant lmsb : nat1 := boolean'pos(l < 0);
-     variable res : compare_type;
-  begin
-     if r'length = 0 then
-        assert NO_WARNING
-           report "NUMERIC_STD.""<="": null argument, returning FALSE"
-           severity warning;
-        return false;
-     end if;
-
-     res := scompare (r, l);
-     return compare_eq <= res;
-  end "<=";
-
-  function shift_left (ARG : UNSIGNED; COUNT: NATURAL) return UNSIGNED
-  is
-     subtype res_type is UNSIGNED (ARG'length - 1 downto 0);
-     alias arg1 : res_type is arg;
-     variable res : res_type := (others => '0');
-  begin
-     if res'length = 0 then
-        return null_UNSIGNED;
-     end if;
-     if count <= arg1'left then
-       res (res'left downto count) := arg1 (arg1'left - count downto 0);
-     end if;
-     return res;
-  end shift_left;
-
-  function shift_right (ARG : UNSIGNED; COUNT: NATURAL) return UNSIGNED
-  is
-     subtype res_type is UNSIGNED (ARG'length - 1 downto 0);
-     alias arg1 : res_type is arg;
-     variable res : res_type := (others => '0');
-  begin
-     if res'length = 0 then
-        return null_UNSIGNED;
-     end if;
-     if count <= arg1'left then
-       res (res'left - count downto 0) := arg1 (arg1'left downto count);
-     end if;
-     return res;
-  end shift_right;
-
-  function rotate_left (ARG : UNSIGNED; COUNT: natural) return UNSIGNED
-  is
-     subtype res_type is UNSIGNED (ARG'length - 1 downto 0);
-     alias arg1 : res_type is arg;
-     variable res : res_type := (others => '0');
-     variable cnt : natural;
-  begin
-     if res'length = 0 then
-        return null_UNSIGNED;
-     end if;
-     cnt := count rem res'length;
-     res (res'left downto cnt) := arg1 (res'left - cnt downto 0);
-     res (cnt - 1 downto 0) := arg1 (res'left downto res'left - cnt + 1);
-     return res;
-  end rotate_left;
-
-  function rotate_right (ARG : UNSIGNED; COUNT: natural) return UNSIGNED
-  is
-     subtype res_type is UNSIGNED (ARG'length - 1 downto 0);
-     alias arg1 : res_type is arg;
-     variable res : res_type := (others => '0');
-     variable cnt : natural;
-  begin
-     if res'length = 0 then
-        return null_UNSIGNED;
-     end if;
-     cnt := count rem res'length;
-     res (res'left - cnt downto 0) := arg1 (res'left downto cnt);
-     res (res'left downto res'left - cnt + 1) := arg1 (cnt - 1 downto 0);
-     return res;
-  end rotate_right;
-
-  function shift_left (ARG : SIGNED; COUNT: NATURAL) return SIGNED
-  is
-     subtype res_type is SIGNED (ARG'length - 1 downto 0);
-     alias arg1 : res_type is arg;
-     variable res : res_type := (others => '0');
-  begin
-     if res'length = 0 then
-        return null_SIGNED;
-     end if;
-     if count <= arg1'left then
-       res (res'left downto count) := arg1 (arg1'left - count downto 0);
-     end if;
-     return res;
-  end shift_left;
-
-  function shift_right (ARG : SIGNED; COUNT: NATURAL) return SIGNED
-  is
-     subtype res_type is SIGNED (ARG'length - 1 downto 0);
-     alias arg1 : res_type is arg;
-     variable res : res_type := (others => arg1 (arg1'left));
-  begin
-     if res'length = 0 then
-        return null_SIGNED;
-     end if;
-     if count <= arg1'left then
-       res (res'left - count downto 0) := arg1 (arg1'left downto count);
-     end if;
-     return res;
-  end shift_right;
-
-  function rotate_left (ARG : SIGNED; COUNT: natural) return SIGNED
-  is
-     subtype res_type is SIGNED (ARG'length - 1 downto 0);
-     alias arg1 : res_type is arg;
-     variable res : res_type := (others => '0');
-     variable cnt : natural;
-  begin
-     if res'length = 0 then
-        return null_SIGNED;
-     end if;
-     cnt := count rem res'length;
-     res (res'left downto cnt) := arg1 (res'left - cnt downto 0);
-     res (cnt - 1 downto 0) := arg1 (res'left downto res'left - cnt + 1);
-     return res;
-  end rotate_left;
-
-  function rotate_right (ARG : SIGNED; COUNT: natural) return SIGNED
-  is
-     subtype res_type is SIGNED (ARG'length - 1 downto 0);
-     alias arg1 : res_type is arg;
-     variable res : res_type := (others => '0');
-     variable cnt : natural;
-  begin
-     if res'length = 0 then
-        return null_SIGNED;
-     end if;
-     cnt := count rem res'length;
-     res (res'left - cnt downto 0) := arg1 (res'left downto cnt);
-     res (res'left downto res'left - cnt + 1) := arg1 (cnt - 1 downto 0);
-     return res;
-  end rotate_right;
-
-  function rising_edge (signal s : bit) return boolean is
-  begin
-    return s'event and s = '1';
-  end rising_edge;
-
-  function falling_edge (signal s : bit) return boolean is
-  begin
-    return s'event and s = '0';
-  end falling_edge;
-end NUMERIC_BIT;