old-autovect-branch/gcc/testsuite/ada/acats/tests/c3/c3a0001.a

   1 -- C3A0001.A
   2 --
   3 --                             Grant of Unlimited Rights
   4 --
   5 --     Under contracts F33600-87-D-0337, F33600-84-D-0280, MDA903-79-C-0687,
   6 --     F08630-91-C-0015, and DCA100-97-D-0025, the U.S. Government obtained
   7 --     unlimited rights in the software and documentation contained herein.
   8 --     Unlimited rights are defined in DFAR 252.227-7013(a)(19).  By making
   9 --     this public release, the Government intends to confer upon all
  10 --     recipients unlimited rights  equal to those held by the Government.
  11 --     These rights include rights to use, duplicate, release or disclose the
  12 --     released technical data and computer software in whole or in part, in
  13 --     any manner and for any purpose whatsoever, and to have or permit others
  14 --     to do so.
  15 --
  16 --                                    DISCLAIMER
  17 --
  18 --     ALL MATERIALS OR INFORMATION HEREIN RELEASED, MADE AVAILABLE OR
  19 --     DISCLOSED ARE AS IS.  THE GOVERNMENT MAKES NO EXPRESS OR IMPLIED
  20 --     WARRANTY AS TO ANY MATTER WHATSOEVER, INCLUDING THE CONDITIONS OF THE
  21 --     SOFTWARE, DOCUMENTATION OR OTHER INFORMATION RELEASED, MADE AVAILABLE
  22 --     OR DISCLOSED, OR THE OWNERSHIP, MERCHANTABILITY, OR FITNESS FOR A
  23 --     PARTICULAR PURPOSE OF SAID MATERIAL.
  24 --*
  25 --
  26 -- OBJECTIVE:
  27 --      Check that access to subprogram type can be used to select and
  28 --      invoke functions with appropriate arguments dynamically.
  29 --
  30 -- TEST DESCRIPTION:
  31 --      Declare an access to function type in a package specification.
  32 --      Declare three different sine functions that can be referred to by
  33 --      the access to function type.
  34 --
  35 --      In the main program, call each function indirectly by dereferencing
  36 --      the access value.
  37 --
  38 --
  39 -- CHANGE HISTORY:
  40 --      06 Dec 94   SAIC    ACVC 2.0
  41 --
  42 --!
  43
  44 package C3A0001_0 is
  45
  46    TC_Call_Tag : Natural := 0;
  47
  48    -- Type accesses to any sine function
  49    type Sine_Function_Ptr is access function
  50       (Angle : in Float) return Float;
  51
  52 -- Three 'Sine' functions that model an application situation in which
  53 -- one function might be chosen when speed is important, another (using
  54 -- a different algorithm) might be chosen when accuracy is important,
  55 -- and so on.
  56
  57    function Sine_Calc_Fast  (Angle : in Float) return Float;
  58
  59    function Sine_Calc_Acc   (Angle : in Float) return Float;
  60
  61    function Sine_Calc_Table (Angle : in Float) return Float;
  62
  63 end C3A0001_0;
  64
  65
  66 -----------------------------------------------------------------------------
  67
  68
  69 package body C3A0001_0 is
  70
  71    function Sine_Calc_Fast (Angle : in Float) return Float is
  72    begin
  73       TC_Call_Tag := 1;
  74       return 1.0;
  75    end Sine_Calc_Fast;
  76
  77
  78    function Sine_Calc_Acc (Angle : in Float) return Float is
  79    begin
  80       TC_Call_Tag := 2;
  81       return 0.0;
  82    end Sine_Calc_Acc;
  83
  84
  85    function Sine_Calc_Table (Angle : in Float) return Float is
  86    begin
  87       TC_Call_Tag := 3;
  88       return -1.0;
  89    end Sine_Calc_Table;
  90
  91 end C3A0001_0;
  92
  93 -----------------------------------------------------------------------------
  94
  95 with Report;
  96 with C3A0001_0;
  97
  98 procedure C3A0001 is
  99
 100    Sine_Access : C3A0001_0.Sine_Function_Ptr;
 101    X, Theta    : Float := 0.0;
 102
 103 begin
 104
 105    Report.Test ("C3A0001", "Check that access to subprogram can be " &
 106                 "used to select and invoke an operation with " &
 107                 "appropriate arguments dynamically");
 108
 109    Sine_Access := C3A0001_0.Sine_Calc_Fast'Access;
 110
 111    -- Invoking Sine function designated by access value
 112    X := Sine_Access(Theta);
 113
 114    If C3A0001_0.TC_Call_Tag /= 1 then
 115       Report.Failed ("Incorrect Sine_Calc_Fast result");
 116    end if;
 117
 118    Sine_Access := C3A0001_0.Sine_Calc_Acc'Access;
 119
 120    -- Invoking Sine function designated by access value
 121    X := Sine_Access(Theta);
 122
 123    If C3A0001_0.TC_Call_Tag /= 2 then
 124       Report.Failed ("Incorrect Sine_Calc_Acc result");
 125    end if;
 126
 127    Sine_Access := C3A0001_0.Sine_Calc_Table'Access;
 128
 129    -- Invoking Sine function designated by access value
 130    X := Sine_Access(Theta);
 131
 132    If C3A0001_0.TC_Call_Tag /= 3 then
 133       Report.Failed ("Incorrect Sine_Calc_Table result");
 134    end if;
 135
 136    Report.Result;
 137
 138 end C3A0001;