From patchwork Mon Mar 24 16:10:37 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joseph Myers X-Patchwork-Id: 333095 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id A5CA1140098 for ; Tue, 25 Mar 2014 03:10:53 +1100 (EST) DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:date:from:to:subject:message-id:mime-version :content-type; q=dns; s=default; b=Ppe8/77v+ffWqn7tP9AN2pCGE4Kgl PXHNTcvcVdCU7EGXjAUCvSNl6J6qnpRZQDeftdWi3sSHVyy97wdVt6T+C4Tpiwno yTzzaoYQhz222rCRJco8i1EqZf5rlnazFEQ4ISzwsa84Wza7qU6wYWmtSWbrg4Ja nSc8CzwE/McDp0= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:date:from:to:subject:message-id:mime-version :content-type; s=default; bh=pPxKTbaWDxNDFh7ojyYOu6ihNdE=; b=n8x TBQxGOCtiD1p/7EQVIitOAueUiOGeXaAQVAw8J6pdsgvn5E/qTHEgXAzi8Kzd3o2 P1Tw2R4ecC6GWojA2O/D/iLoq6Jykc4a7mDmOTemHQItYK55l0f8g4HXnHteLepG leJRvijF1M55pxeQao5IWk9XxxQ8RXZKllI8bhGo= Received: (qmail 28096 invoked by alias); 24 Mar 2014 16:10:47 -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 28079 invoked by uid 89); 24 Mar 2014 16:10:46 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.0 required=5.0 tests=AWL, BAYES_00 autolearn=ham version=3.3.2 X-HELO: relay1.mentorg.com Date: Mon, 24 Mar 2014 16:10:37 +0000 From: "Joseph S. Myers" To: Subject: Relax gen-auto-libm-tests may-underflow rules, test log1p in all rounding modes Message-ID: MIME-Version: 1.0 gen-auto-libm-tests presently allows but does not require underflow exceptions for results with magnitude in the range (greatest subnormal, least normal]. In some cases, the magnitude of the exact result is very slightly above the least normal, but rounding in the implementation results in it effectively computing an infinite-precision result that is slightly below the least normal, so raising an underflow exception. This is in accordance with the documented accuracy goals, but results in testsuite failures. This patch changes the logic to allow underflows when the mathematical result is up to 0.5ulp above the least normal (so in any case where the round-to-nearest result is the least normal). Ideally underflows in all these cases would be accepted only when an underflow with the actual result is consistent with the rounding mode (in FE_TOWARDZERO mode, a return value of the least normal implies that the infinite-precision result did not underflow so there should be no underflow exception, for example), so as to match the documented goals more precisely - whereas at present the tests for exceptions are completely independent of the tests of the returned values. (The same applies to overflow exceptions as well - they too should be checked for consistency with the result, as in FE_TOWARDZERO mode a result 1ulp below the largest finite value should be inconsistent with an overflow exception and cause a failure with overflow rather than simply being considered a 1ulp error when overflow is expected.) But the present patch at least deals with the cases causing spurious failures so that (a) certain existing tests no longer need to be marked as having spurious exceptions (such markings in auto-libm-test-in end up applying to more cases than just those they are needed for) and (b) log1p can be tested in all rounding modes without introducing more such failures. This patch duly moves tests of log1p to ALL_RM_TEST. Tested x86_64 and x86 and ulps updated accordingly. (auto-libm-test-out changes omitted below.) 2014-03-24 Joseph Myers [BZ #16357] [BZ #16599] * math/gen-auto-libm-tests.c (fp_format_desc): Add field min_plus_half. (fp_formats): Update initializers. (init_fp_formats): Initialize new field. (output_for_one_input_case): Allow underflow for results up to min_plus_half. * math/libm-test.inc (log1p_test): Use ALL_RM_TEST. * math/auto-libm-test-in: Don't mark some underflows from asin and atanh as spurious. * math/auto-libm-test-out: Regenerated. * sysdeps/i386/fpu/libm-test-ulps: Update. * sysdeps/x86_64/fpu/libm-test-ulps: Likewise. diff --git a/math/auto-libm-test-in b/math/auto-libm-test-in index 5975631..7c80192 100644 --- a/math/auto-libm-test-in +++ b/math/auto-libm-test-in @@ -61,9 +61,8 @@ asin -0x0.ffffffffffffp0 asin 0x0.ffffffffffffffffp0 asin -0x0.ffffffffffffffffp0 # Bug 16351: underflow exception may be missing. -# Bug 16599: spurious underflow may occur. asin min missing-underflow -asin -min missing-underflow spurious-underflow:dbl-64:x86 +asin -min missing-underflow asin min_subnorm missing-underflow asin -min_subnorm missing-underflow @@ -175,9 +174,8 @@ atanh 0x1p-5 atanh 0x1p-10 atanh 0x1.2345p-20 # Bug 16352: underflow exception may be missing. -# Bug 16357: spurious underflow may occur. -atanh min missing-underflow spurious-underflow:ldbl-96-intel:x86 -atanh -min missing-underflow spurious-underflow:ldbl-96-intel:x86 +atanh min missing-underflow +atanh -min missing-underflow atanh min_subnorm missing-underflow atanh -min_subnorm missing-underflow diff --git a/math/gen-auto-libm-tests.c b/math/gen-auto-libm-tests.c index 61097e4..132cca2 100644 --- a/math/gen-auto-libm-tests.c +++ b/math/gen-auto-libm-tests.c @@ -171,6 +171,8 @@ typedef struct int min_exp; /* The largest normal value. */ mpfr_t max; + /* The value 0.5ulp above the least positive normal value. */ + mpfr_t min_plus_half; /* The least positive normal value, 2^(MIN_EXP-1). */ mpfr_t min; /* The greatest positive subnormal value. */ @@ -183,13 +185,13 @@ typedef struct enumeration. */ static fp_format_desc fp_formats[fp_num_formats] = { - { "flt-32", "f", NULL, 24, 128, -125, {}, {}, {}, {} }, - { "dbl-64", "", NULL, 53, 1024, -1021, {}, {}, {}, {} }, - { "ldbl-96-intel", "L", NULL, 64, 16384, -16381, {}, {}, {}, {} }, - { "ldbl-96-m68k", "L", NULL, 64, 16384, -16382, {}, {}, {}, {} }, - { "ldbl-128", "L", NULL, 113, 16384, -16381, {}, {}, {}, {} }, + { "flt-32", "f", NULL, 24, 128, -125, {}, {}, {}, {}, {} }, + { "dbl-64", "", NULL, 53, 1024, -1021, {}, {}, {}, {}, {} }, + { "ldbl-96-intel", "L", NULL, 64, 16384, -16381, {}, {}, {}, {}, {} }, + { "ldbl-96-m68k", "L", NULL, 64, 16384, -16382, {}, {}, {}, {}, {} }, + { "ldbl-128", "L", NULL, 113, 16384, -16381, {}, {}, {}, {}, {} }, { "ldbl-128ibm", "L", "0x1.fffffffffffff7ffffffffffff8p+1023", - 106, 1024, -968, {}, {}, {}, {} }, + 106, 1024, -968, {}, {}, {}, {}, {} }, }; /* The supported rounding modes. */ @@ -702,6 +704,10 @@ init_fp_formats () assert_exact (mpfr_set_ui_2exp (fp_formats[f].min, 1, fp_formats[f].min_exp - 1, MPFR_RNDN)); + mpfr_init2 (fp_formats[f].min_plus_half, fp_formats[f].mant_dig + 1); + assert_exact (mpfr_set (fp_formats[f].min_plus_half, + fp_formats[f].min, MPFR_RNDN)); + mpfr_nextabove (fp_formats[f].min_plus_half); mpfr_init2 (fp_formats[f].subnorm_max, fp_formats[f].mant_dig); assert_exact (mpfr_set (fp_formats[f].subnorm_max, fp_formats[f].min, MPFR_RNDN)); @@ -1841,8 +1847,9 @@ output_for_one_input_case (FILE *fp, const char *filename, test_function *tf, <= 0)); may_underflow |= (!mpfr_zero_p (generic_outputs[i].value.f) - && mpfr_cmpabs (generic_outputs[i].value.f, - fp_formats[f].min) <= 0); + && (mpfr_cmpabs (generic_outputs[i].value.f, + fp_formats[f].min_plus_half) + <= 0)); } /* If the result is an exact zero, the sign may depend on the rounding mode, so recompute it diff --git a/math/libm-test.inc b/math/libm-test.inc index a8ebecd..9c4c2bf 100644 --- a/math/libm-test.inc +++ b/math/libm-test.inc @@ -7823,9 +7823,7 @@ static const struct test_f_f_data log1p_test_data[] = static void log1p_test (void) { - START (log1p, 0); - RUN_TEST_LOOP_f_f (log1p, log1p_test_data, ); - END; + ALL_RM_TEST (log1p, 0, log1p_test_data, RUN_TEST_LOOP_f_f, END); } diff --git a/sysdeps/i386/fpu/libm-test-ulps b/sysdeps/i386/fpu/libm-test-ulps index 1885be7..a82de19 100644 --- a/sysdeps/i386/fpu/libm-test-ulps +++ b/sysdeps/i386/fpu/libm-test-ulps @@ -1288,6 +1288,30 @@ Function: "log1p": ildouble: 1 ldouble: 1 +Function: "log1p_downward": +double: 1 +float: 1 +idouble: 1 +ifloat: 1 +ildouble: 2 +ldouble: 2 + +Function: "log1p_towardzero": +double: 1 +float: 1 +idouble: 1 +ifloat: 1 +ildouble: 2 +ldouble: 2 + +Function: "log1p_upward": +double: 1 +float: 1 +idouble: 1 +ifloat: 1 +ildouble: 1 +ldouble: 1 + Function: "log_downward": ildouble: 1 ldouble: 1 diff --git a/sysdeps/x86_64/fpu/libm-test-ulps b/sysdeps/x86_64/fpu/libm-test-ulps index 670f2da..e2fa9b2 100644 --- a/sysdeps/x86_64/fpu/libm-test-ulps +++ b/sysdeps/x86_64/fpu/libm-test-ulps @@ -1362,6 +1362,30 @@ ifloat: 1 ildouble: 1 ldouble: 1 +Function: "log1p_downward": +double: 1 +float: 1 +idouble: 1 +ifloat: 1 +ildouble: 2 +ldouble: 2 + +Function: "log1p_towardzero": +double: 1 +float: 1 +idouble: 1 +ifloat: 1 +ildouble: 2 +ldouble: 2 + +Function: "log1p_upward": +double: 1 +float: 1 +idouble: 1 +ifloat: 1 +ildouble: 1 +ldouble: 1 + Function: "log_downward": float: 1 ifloat: 1