| -- C35902D.ADA |
| |
| -- 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. |
| --* |
| -- CHECK THAT THE BINARY POINT IN THE MANTISSA OF A FIXED POINT NUMBER |
| -- CAN LIE OUTSIDE THE MANTISSA (EITHER TO THE LEFT OR TO THE RIGHT). |
| |
| -- WRG 7/18/86 |
| |
| WITH REPORT; USE REPORT; |
| WITH SYSTEM; USE SYSTEM; |
| PROCEDURE C35902D IS |
| |
| BEGIN |
| |
| TEST ("C35902D", "CHECK THAT THE BINARY POINT IN THE MANTISSA " & |
| "OF A FIXED POINT NUMBER CAN LIE OUTSIDE THE " & |
| "MANTISSA (EITHER TO THE LEFT OR TO THE RIGHT)"); |
| |
| COMMENT ("VALUE OF SYSTEM.MAX_MANTISSA IS" & |
| POSITIVE'IMAGE(MAX_MANTISSA) ); |
| |
| A: DECLARE |
| |
| RS : CONSTANT := 2.0; |
| |
| TYPE ONE_TO_THE_RIGHT IS |
| DELTA RS |
| RANGE -(2.0 ** (MAX_MANTISSA+1) ) .. |
| 2.0 ** (MAX_MANTISSA+1); |
| -- THE BINARY POINT IS ONE PLACE TO THE RIGHT OF THE |
| -- LARGEST POSSIBLE MANTISSA. |
| |
| R1, R2 : ONE_TO_THE_RIGHT; |
| |
| BEGIN |
| |
| R1 := RS; |
| FOR I IN POSITIVE RANGE 1 .. MAX_MANTISSA - 1 LOOP |
| R1 := R1 * IDENT_INT (2); |
| END LOOP; |
| R2 := R1 - RS; |
| R2 := R2 + R1; |
| -- AT THIS POINT, R2 SHOULD EQUAL ONE_TO_THE_RIGHT'LARGE. |
| R2 := -R2; |
| R2 := R2 + (R1 - RS); |
| FOR I IN POSITIVE RANGE 1 .. MAX_MANTISSA - 1 LOOP |
| R2 := R2 / IDENT_INT (2); |
| END LOOP; |
| IF R2 /= -RS THEN |
| FAILED ("IDENTITY-PRESERVING OPERATIONS ARE FLAKY - A"); |
| END IF; |
| |
| EXCEPTION |
| |
| WHEN OTHERS => |
| FAILED ("EXCEPTION RAISED - A"); |
| |
| END A; |
| |
| B: DECLARE |
| |
| LS : CONSTANT := 2.0 ** (-(MAX_MANTISSA+1) ); |
| |
| TYPE ONE_TO_THE_LEFT IS |
| DELTA LS |
| RANGE -(2.0 ** (-1) ) .. |
| 2.0 ** (-1); |
| -- THE BINARY POINT IS ONE PLACE TO THE LEFT OF THE |
| -- LARGEST POSSIBLE MANTISSA. |
| |
| L1, L2 : ONE_TO_THE_LEFT; |
| |
| BEGIN |
| |
| L1 := LS; |
| FOR I IN POSITIVE RANGE 1 .. MAX_MANTISSA - 1 LOOP |
| L1 := L1 * IDENT_INT (2); |
| END LOOP; |
| L2 := L1 - LS; |
| L2 := L2 + L1; |
| -- AT THIS POINT, L2 SHOULD EQUAL ONE_TO_THE_LEFT'LARGE. |
| L2 := -L2; |
| L2 := L2 + (L1 - LS); |
| FOR I IN POSITIVE RANGE 1 .. MAX_MANTISSA - 1 LOOP |
| L2 := L2 / IDENT_INT (2); |
| END LOOP; |
| IF L2 /= -LS THEN |
| FAILED ("IDENTITY-PRESERVING OPERATIONS ARE FLAKY - B"); |
| END IF; |
| |
| EXCEPTION |
| |
| WHEN OTHERS => |
| FAILED ("EXCEPTION RAISED - B"); |
| |
| END B; |
| |
| RESULT; |
| |
| END C35902D; |