From patchwork Wed Dec 6 21:36:35 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joseph Myers X-Patchwork-Id: 24763 Received: (qmail 79439 invoked by alias); 6 Dec 2017 21:36:42 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 79427 invoked by uid 89); 6 Dec 2017 21:36:42 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-24.5 required=5.0 tests=AWL, BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, RCVD_IN_DNSWL_NONE, SPF_PASS, URIBL_RED autolearn=ham version=3.3.2 spammy= X-HELO: relay1.mentorg.com Date: Wed, 6 Dec 2017 21:36:35 +0000 From: Joseph Myers To: Subject: Make cacosh (0 + iNaN) return NaN + i pi/2 (bug 22561, DR#471) [committed] Message-ID: User-Agent: Alpine 2.20 (DEB 67 2015-01-07) MIME-Version: 1.0 X-ClientProxiedBy: SVR-IES-MBX-03.mgc.mentorg.com (139.181.222.3) To SVR-IES-MBX-03.mgc.mentorg.com (139.181.222.3) As per C11 DR#471 (adjusted resolution accepted for C17), cacosh (0 + iNaN) should return NaN +/- i pi/2, not NaN + iNaN. This patch fixes the code accordingly. The test has hardcoded the result with positive sign of the imaginary part (with an associated comment), since the unspecified sign for a result other than 0 or infinity isn't currently supported by the test infrastructure. Tested for x86_64. Committed. 2017-12-06 Joseph Myers [BZ #22561] * math/s_cacosh_template.c (M_DECL_FUNC (__cacosh)): Use pi/2 for real part of result for argument 0 + i * NaN. * math/libm-test-cacosh.inc (cacosh_test_data): Update expected results for tests of 0 + i * NaN. diff --git a/math/libm-test-cacosh.inc b/math/libm-test-cacosh.inc index 518cb29..db700b9 100644 --- a/math/libm-test-cacosh.inc +++ b/math/libm-test-cacosh.inc @@ -46,8 +46,13 @@ static const struct test_c_c_data cacosh_test_data[] = TEST_c_c (cacosh, plus_infty, qnan_value, plus_infty, qnan_value), TEST_c_c (cacosh, minus_infty, qnan_value, plus_infty, qnan_value), - TEST_c_c (cacosh, 0, qnan_value, qnan_value, qnan_value), - TEST_c_c (cacosh, minus_zero, qnan_value, qnan_value, qnan_value), + /* The sign of the imaginary part of the result is unspecified + (see + ), + but the libm-test infrastructure does not support describing + that. */ + TEST_c_c (cacosh, 0, qnan_value, qnan_value, lit_pi_2_d), + TEST_c_c (cacosh, minus_zero, qnan_value, qnan_value, lit_pi_2_d), TEST_c_c (cacosh, qnan_value, plus_infty, plus_infty, qnan_value), TEST_c_c (cacosh, qnan_value, minus_infty, plus_infty, qnan_value), diff --git a/math/s_cacosh_template.c b/math/s_cacosh_template.c index 14f0b2a..0014fd4 100644 --- a/math/s_cacosh_template.c +++ b/math/s_cacosh_template.c @@ -57,7 +57,10 @@ M_DECL_FUNC (__cacosh) (CFLOAT x) else { __real__ res = M_NAN; - __imag__ res = M_NAN; + if (rcls == FP_ZERO) + __imag__ res = M_MLIT (M_PI_2); + else + __imag__ res = M_NAN; } } else if (rcls == FP_ZERO && icls == FP_ZERO)