fxf2a00.a

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-- FXF2A00.A
--
--                             Grant of Unlimited Rights
--
--     Under contracts F33600-87-D-0337, F33600-84-D-0280, MDA903-79-C-0687,
--     F08630-91-C-0015, and DCA100-97-D-0025, the U.S. Government obtained 
--     unlimited rights in the software and documentation contained herein.
--     Unlimited rights are defined in DFAR 252.227-7013(a)(19).  By making 
--     this public release, the Government intends to confer upon all 
--     recipients unlimited rights  equal to those held by the Government.  
--     These rights include rights to use, duplicate, release or disclose the 
--     released technical data and computer software in whole or in part, in 
--     any manner and for any purpose whatsoever, and to have or permit others 
--     to do so.
--
--                                    DISCLAIMER
--
--     ALL MATERIALS OR INFORMATION HEREIN RELEASED, MADE AVAILABLE OR
--     DISCLOSED ARE AS IS.  THE GOVERNMENT MAKES NO EXPRESS OR IMPLIED 
--     WARRANTY AS TO ANY MATTER WHATSOEVER, INCLUDING THE CONDITIONS OF THE
--     SOFTWARE, DOCUMENTATION OR OTHER INFORMATION RELEASED, MADE AVAILABLE 
--     OR DISCLOSED, OR THE OWNERSHIP, MERCHANTABILITY, OR FITNESS FOR A
--     PARTICULAR PURPOSE OF SAID MATERIAL.
--*
--
-- FOUNDATION DESCRIPTION:
--      This foundation declares supporting objects, types and a generic
--      function for testing decimal fixed point operations.
--
--      The generic function contains a loop which steps through two arrays:
--      one of binary operations and one of operands. For each iteration, the
--      current operation is performed on the current operand and a variable
--      "Result" e.g.:
--
--                   Result := Operation(2)(Operand(3), Result);
--
--      The result of each operation is cumulated in Result and returned to
--      the caller when the loop completes.
--
-- CHANGE HISTORY:
--      12 Mar 96   SAIC    Prerelease version for ACVC 2.1.
--
--!

package FXF2A00 is

   Loop_Count : constant := 30000;             -- # test iterations.
   Optr_Count : constant :=     6;             -- # operations in op sequence.
   Opnd_Count : constant :=     5;             -- # different operands.

   type Loop_Range is range 1 .. Loop_Count;   -- range 1 .. 30000.
   type Optr_Range is mod Optr_Count;          -- range 0 .. 5.
   type Opnd_Range is mod Opnd_Count;          -- range 0 .. 4.


   generic

      type Decimal_Fixed is delta <> digits <>;

      type Operator_Ptr is access
        function (L, R : Decimal_Fixed) return Decimal_Fixed;

      type Operator_Table is array (Optr_Range) of Operator_Ptr;
      type Operand_Table  is array (Opnd_Range) of Decimal_Fixed;

   function Operations_Loop (Initial : Decimal_Fixed;
                             Operator: Operator_Table;
                             Operand : Operand_Table) return Decimal_Fixed;

end FXF2A00;


     --==================================================================--


package body FXF2A00 is

   function Operations_Loop (Initial : Decimal_Fixed;
                             Operator: Operator_Table;
                             Operand : Operand_Table) return Decimal_Fixed is

      Result     : Decimal_Fixed := Initial;  -- Cumulator.
      Optr_Index : Optr_Range := 0;           -- Index into operations table.
      Opnd_Index : Opnd_Range := 0;           -- Index into operand table.

   begin
      for Count in Loop_Range loop
         Result     := Operator(Optr_Index) (Result, Operand(Opnd_Index));
         Optr_Index := Optr_Index + 1;        -- Modular addition.
         Opnd_Index := Opnd_Index + 1;        -- Modular addition.
      end loop;

      return Result;
   end Operations_Loop;

end FXF2A00;