diff options
-rw-r--r-- | ChangeLog | 7 | ||||
-rw-r--r-- | sysdeps/ieee754/ldbl-128ibm/Makefile | 4 | ||||
-rw-r--r-- | sysdeps/ieee754/ldbl-128ibm/e_fmodl.c | 7 | ||||
-rw-r--r-- | sysdeps/ieee754/ldbl-128ibm/test-fmodl-ldbl-128ibm.c | 77 |
4 files changed, 95 insertions, 0 deletions
@@ -1,5 +1,12 @@ 2016-02-18 Joseph Myers <joseph@codesourcery.com> + [BZ #19602] + * sysdeps/ieee754/ldbl-128ibm/e_fmodl.c (__ieee754_fmodl): Handle + equal high parts and both low parts zero specially. + * sysdeps/ieee754/ldbl-128ibm/test-fmodl-ldbl-128ibm.c: New test. + * sysdeps/ieee754/ldbl-128ibm/Makefile [$(subdir) = math] (tests): + Add test-fmodl-ldbl-128ibm. + [BZ #19595] * sysdeps/ieee754/ldbl-128ibm/e_fmodl.c (__ieee754_fmodl): Use common logic for all cases of shifting subnormal results. Do not diff --git a/sysdeps/ieee754/ldbl-128ibm/Makefile b/sysdeps/ieee754/ldbl-128ibm/Makefile index 5591814824..b633172721 100644 --- a/sysdeps/ieee754/ldbl-128ibm/Makefile +++ b/sysdeps/ieee754/ldbl-128ibm/Makefile @@ -8,3 +8,7 @@ ifeq ($(subdir),stdlib) tests += tst-strtold-ldbl-128ibm $(objpfx)tst-strtold-ldbl-128ibm: $(libm) endif + +ifeq ($(subdir),math) +tests += test-fmodl-ldbl-128ibm +endif diff --git a/sysdeps/ieee754/ldbl-128ibm/e_fmodl.c b/sysdeps/ieee754/ldbl-128ibm/e_fmodl.c index d756e3e2a6..5284fd0fd5 100644 --- a/sysdeps/ieee754/ldbl-128ibm/e_fmodl.c +++ b/sysdeps/ieee754/ldbl-128ibm/e_fmodl.c @@ -55,6 +55,13 @@ __ieee754_fmodl (long double x, long double y) return x; /* At this point the absolute value of the high doubles of x and y must be equal. */ + if ((lx & 0x7fffffffffffffffLL) == 0 + && (ly & 0x7fffffffffffffffLL) == 0) + /* Both low parts are zero. The result should be an + appropriately signed zero, but the subsequent logic + could treat them as unequal, depending on the signs + of the low parts. */ + return Zero[(uint64_t) sx >> 63]; /* If the low double of y is the same sign as the high double of y (ie. the low double increases |y|)... */ if (((ly ^ sy) & 0x8000000000000000LL) == 0 diff --git a/sysdeps/ieee754/ldbl-128ibm/test-fmodl-ldbl-128ibm.c b/sysdeps/ieee754/ldbl-128ibm/test-fmodl-ldbl-128ibm.c new file mode 100644 index 0000000000..3717c90aba --- /dev/null +++ b/sysdeps/ieee754/ldbl-128ibm/test-fmodl-ldbl-128ibm.c @@ -0,0 +1,77 @@ +/* Test for ldbl-128ibm fmodl handling of equal values (bug 19602). + Copyright (C) 2016 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#include <float.h> +#include <math.h> +#include <stdio.h> + +union u +{ + long double ld; + double d[2]; +}; + +volatile union u p1 = { .d = { DBL_MIN, 0.0 } }; +volatile union u p2 = { .d = { DBL_MIN, -0.0 } }; +volatile union u m1 = { .d = { -DBL_MIN, 0.0 } }; +volatile union u m2 = { .d = { -DBL_MIN, -0.0 } }; + +static int +test_fmodl (const char *s, long double x, long double y, long double expected) +{ + volatile long double r; + r = fmodl (x, y); + if (r != expected || copysignl (1.0, r) != copysignl (1.0, expected)) + { + printf ("FAIL: fmodl (%s)\n", s); + return 1; + } + else + { + printf ("PASS: fmodl (%s)\n", s); + return 0; + } +} + +#define TEST_FMODL(a, b, e) test_fmodl (#a ", " #b, a, b, e) + +static int +do_test (void) +{ + int result = 0; + result |= TEST_FMODL (p1.ld, p1.ld, 0.0L); + result |= TEST_FMODL (p1.ld, p2.ld, 0.0L); + result |= TEST_FMODL (p1.ld, m1.ld, 0.0L); + result |= TEST_FMODL (p1.ld, m2.ld, 0.0L); + result |= TEST_FMODL (p2.ld, p1.ld, 0.0L); + result |= TEST_FMODL (p2.ld, p2.ld, 0.0L); + result |= TEST_FMODL (p2.ld, m1.ld, 0.0L); + result |= TEST_FMODL (p2.ld, m2.ld, 0.0L); + result |= TEST_FMODL (m1.ld, p1.ld, -0.0L); + result |= TEST_FMODL (m1.ld, p2.ld, -0.0L); + result |= TEST_FMODL (m1.ld, m1.ld, -0.0L); + result |= TEST_FMODL (m1.ld, m2.ld, -0.0L); + result |= TEST_FMODL (m2.ld, p1.ld, -0.0L); + result |= TEST_FMODL (m2.ld, p2.ld, -0.0L); + result |= TEST_FMODL (m2.ld, m1.ld, -0.0L); + result |= TEST_FMODL (m2.ld, m2.ld, -0.0L); + return result; +} + +#define TEST_FUNCTION do_test () +#include "../../../test-skeleton.c" |