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diff --git a/gcc/testsuite/ada/acats/tests/cxg/cxg2017.a b/gcc/testsuite/ada/acats/tests/cxg/cxg2017.a new file mode 100644 index 000000000..50add975f --- /dev/null +++ b/gcc/testsuite/ada/acats/tests/cxg/cxg2017.a @@ -0,0 +1,296 @@ +-- CXG2017.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. +--* +-- +-- OBJECTIVE: +-- Check that the TANH function returns +-- a result that is within the error bound allowed. +-- +-- TEST DESCRIPTION: +-- This test consists of a generic package that is +-- instantiated to check both Float and a long float type. +-- The test for each floating point type is divided into +-- several parts: +-- Special value checks where the result is a known constant. +-- Checks that use an identity for determining the result. +-- +-- SPECIAL REQUIREMENTS +-- The Strict Mode for the numerical accuracy must be +-- selected. The method by which this mode is selected +-- is implementation dependent. +-- +-- APPLICABILITY CRITERIA: +-- This test applies only to implementations supporting the +-- Numerics Annex. +-- This test only applies to the Strict Mode for numerical +-- accuracy. +-- +-- +-- CHANGE HISTORY: +-- 20 Mar 96 SAIC Initial release for 2.1 +-- 17 Aug 96 SAIC Incorporated reviewer comments. +-- 03 Jun 98 EDS Add parens to remove the potential for overflow. +-- Remove the invocation of Identity_Test that checks +-- Tanh values that are too close to zero for the +-- test's error bounds. +--! + +-- +-- References: +-- +-- Software Manual for the Elementary Functions +-- William J. Cody, Jr. and William Waite +-- Prentice-Hall, 1980 +-- +-- CRC Standard Mathematical Tables +-- 23rd Edition +-- +-- Implementation and Testing of Function Software +-- W. J. Cody +-- Problems and Methodologies in Mathematical Software Production +-- editors P. C. Messina and A. Murli +-- Lecture Notes in Computer Science Volume 142 +-- Springer Verlag, 1982 +-- + +with System; +with Report; +with Ada.Numerics.Generic_Elementary_Functions; +procedure CXG2017 is + Verbose : constant Boolean := False; + Max_Samples : constant := 1000; + + E : constant := Ada.Numerics.E; + + generic + type Real is digits <>; + package Generic_Check is + procedure Do_Test; + end Generic_Check; + + package body Generic_Check is + package Elementary_Functions is new + Ada.Numerics.Generic_Elementary_Functions (Real); + + function Tanh (X : Real) return Real renames + Elementary_Functions.Tanh; + + function Log (X : Real) return Real renames + Elementary_Functions.Log; + + -- flag used to terminate some tests early + Accuracy_Error_Reported : Boolean := False; + + + -- The following value is a lower bound on the accuracy + -- required. It is normally 0.0 so that the lower bound + -- is computed from Model_Epsilon. However, for tests + -- where the expected result is only known to a certain + -- amount of precision this bound takes on a non-zero + -- value to account for that level of precision. + Error_Low_Bound : Real := 0.0; + + procedure Check (Actual, Expected : Real; + Test_Name : String; + MRE : Real) is + Max_Error : Real; + Rel_Error : Real; + Abs_Error : Real; + begin + -- In the case where the expected result is very small or 0 + -- we compute the maximum error as a multiple of Model_Small instead + -- of Model_Epsilon and Expected. + Rel_Error := MRE * abs Expected * Real'Model_Epsilon; + Abs_Error := MRE * Real'Model_Small; + if Rel_Error > Abs_Error then + Max_Error := Rel_Error; + else + Max_Error := Abs_Error; + end if; + -- take into account the low bound on the error + if Max_Error < Error_Low_Bound then + Max_Error := Error_Low_Bound; + end if; + + if abs (Actual - Expected) > Max_Error then + Accuracy_Error_Reported := True; + Report.Failed (Test_Name & + " actual: " & Real'Image (Actual) & + " expected: " & Real'Image (Expected) & + " difference: " & Real'Image (Actual - Expected) & + " max err:" & Real'Image (Max_Error) ); + elsif Verbose then + if Actual = Expected then + Report.Comment (Test_Name & " exact result"); + else + Report.Comment (Test_Name & " passed"); + end if; + end if; + end Check; + + + procedure Special_Value_Test is + -- In the following tests the expected result is accurate + -- to the machine precision so the minimum guaranteed error + -- bound can be used. + Minimum_Error : constant := 8.0; + E2 : constant := E * E; + begin + Check (Tanh (1.0), + (E - 1.0 / E) / (E + 1.0 / E), + "tanh(1)", + Minimum_Error); + Check (Tanh (2.0), + (E2 - 1.0 / E2) / (E2 + 1.0 / E2), + "tanh(2)", + Minimum_Error); + exception + when Constraint_Error => + Report.Failed ("Constraint_Error raised in special value test"); + when others => + Report.Failed ("exception in special value test"); + end Special_Value_Test; + + + + procedure Exact_Result_Test is + No_Error : constant := 0.0; + begin + -- A.5.1(38);6.0 + Check (Tanh (0.0), 0.0, "tanh(0)", No_Error); + exception + when Constraint_Error => + Report.Failed ("Constraint_Error raised in Exact_Result Test"); + when others => + Report.Failed ("exception in Exact_Result Test"); + end Exact_Result_Test; + + + procedure Identity_Test (A, B : Real) is + -- For this test we use the identity + -- TANH(u+v) = [TANH(u) + TANH(v)] / [1 + TANH(u)*TANH(v)] + -- which is transformed to + -- TANH(x) = [TANH(y)+C] / [1 + TANH(y) * C] + -- where C = TANH(1/8) and y = x - 1/8 + -- + -- see Cody pg 248-249 for details on the error analysis. + -- The net result is a relative error bound of 16 * Model_Epsilon. + -- + -- The second part of this test checks the identity + -- TANH(-x) = -TANH(X) + + X, Y : Real; + Actual1, Actual2 : Real; + C : constant := 1.2435300177159620805e-1; + begin + if Real'Digits > 20 then + -- constant C is accurate to 20 digits. Set the low bound + -- on the error to 16*10**-20 + Error_Low_Bound := 0.00000_00000_00000_00016; + Report.Comment ("tanh accuracy checked to 20 digits"); + end if; + + Accuracy_Error_Reported := False; -- reset + for I in 1..Max_Samples loop + X := (B - A) * (Real (I) / Real (Max_Samples)) + A; + Actual1 := Tanh(X); + + -- TANH(x) = [TANH(y)+C] / [1 + TANH(y) * C] + Y := X - (1.0 / 8.0); + Actual2 := (Tanh (Y) + C) / (1.0 + Tanh(Y) * C); + + Check (Actual1, Actual2, + "Identity_1_Test " & Integer'Image (I) & ": tanh(" & + Real'Image (X) & ") ", + 16.0); + + -- TANH(-x) = -TANH(X) + Actual2 := Tanh(-X); + Check (-Actual1, Actual2, + "Identity_2_Test " & Integer'Image (I) & ": tanh(" & + Real'Image (X) & ") ", + 16.0); + + if Accuracy_Error_Reported then + -- only report the first error in this test in order to keep + -- lots of failures from producing a huge error log + return; + end if; + + end loop; + Error_Low_Bound := 0.0; -- reset + exception + when Constraint_Error => + Report.Failed + ("Constraint_Error raised in Identity_Test" & + " for X=" & Real'Image (X)); + when others => + Report.Failed ("exception in Identity_Test" & + " for X=" & Real'Image (X)); + end Identity_Test; + + + + procedure Do_Test is + begin + Special_Value_Test; + Exact_Result_Test; + -- cover a large range + Identity_Test (1.0, Real'Safe_Last); + end Do_Test; + end Generic_Check; + + ----------------------------------------------------------------------- + ----------------------------------------------------------------------- + package Float_Check is new Generic_Check (Float); + + -- check the floating point type with the most digits + type A_Long_Float is digits System.Max_Digits; + package A_Long_Float_Check is new Generic_Check (A_Long_Float); + + ----------------------------------------------------------------------- + ----------------------------------------------------------------------- + + +begin + Report.Test ("CXG2017", + "Check the accuracy of the TANH function"); + + if Verbose then + Report.Comment ("checking Standard.Float"); + end if; + + Float_Check.Do_Test; + + if Verbose then + Report.Comment ("checking a digits" & + Integer'Image (System.Max_Digits) & + " floating point type"); + end if; + + A_Long_Float_Check.Do_Test; + + + Report.Result; +end CXG2017; |