From 01dbacd22a8d5e0053f8d0cf13a80286b6cfe79b Mon Sep 17 00:00:00 2001 From: Joseph Myers Date: Wed, 14 May 2014 12:37:24 +0000 Subject: [PATCH] Fix cacos (+Inf + finite*i) in round-downward mode (bug 16928). According to C99/C11 Annex G, cacos applied to a value with real part +Inf and finite imaginary part should produce a result with real part +0. glibc wrongly produces a result with real part -0 in FE_DOWNWARD mode. This patch fixes this by checking for zero results in the relevant case of non-finite arguments (where there should never be a result with -0 real part), and converts the tests of cacos to ALL_RM_TEST. Tested x86_64 and x86 and ulps updated accordingly. [BZ #16928] * math/s_cacos.c (__cacos): Ensure zero real part of result from non-finite arguments is +0. * math/s_cacosf.c (__cacosf): Likewise. * math/s_cacosl.c (__cacosl): Likewise. * math/libm-test.inc (cacos_test): Use ALL_RM_TEST. * sysdeps/i386/fpu/libm-test-ulps: Update. * sysdeps/x86_64/fpu/libm-test-ulps: Likewise. --- ChangeLog | 9 ++++++++ NEWS | 2 +- math/libm-test.inc | 4 +--- math/s_cacos.c | 2 ++ math/s_cacosf.c | 2 ++ math/s_cacosl.c | 2 ++ sysdeps/i386/fpu/libm-test-ulps | 48 +++++++++++++++++++++++++++++++++++++++ sysdeps/x86_64/fpu/libm-test-ulps | 48 +++++++++++++++++++++++++++++++++++++++ 8 files changed, 113 insertions(+), 4 deletions(-) diff --git a/ChangeLog b/ChangeLog index a437629..37ca8c0 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,14 @@ 2014-05-14 Joseph Myers + [BZ #16928] + * math/s_cacos.c (__cacos): Ensure zero real part of result from + non-finite arguments is +0. + * math/s_cacosf.c (__cacosf): Likewise. + * math/s_cacosl.c (__cacosl): Likewise. + * math/libm-test.inc (cacos_test): Use ALL_RM_TEST. + * sysdeps/i386/fpu/libm-test-ulps: Update. + * sysdeps/x86_64/fpu/libm-test-ulps: Likewise. + [BZ #16927] * sysdeps/i386/fpu/e_acosh.S (__ieee754_acosh): Use fabs on x-1 value. diff --git a/NEWS b/NEWS index 974d2c8..de9e8a2 100644 --- a/NEWS +++ b/NEWS @@ -17,7 +17,7 @@ Version 2.20 16713, 16714, 16731, 16739, 16740, 16743, 16754, 16758, 16759, 16760, 16770, 16786, 16789, 16791, 16799, 16800, 16815, 16823, 16824, 16831, 16838, 16854, 16876, 16877, 16885, 16888, 16890, 16912, 16916, 16922, - 16927, 16932. + 16927, 16928, 16932. * The minimum Linux kernel version that this version of the GNU C Library can be used with is 2.6.32. diff --git a/math/libm-test.inc b/math/libm-test.inc index b4177e8..de7bc8a 100644 --- a/math/libm-test.inc +++ b/math/libm-test.inc @@ -2615,9 +2615,7 @@ static const struct test_c_c_data cacos_test_data[] = static void cacos_test (void) { - START (cacos, 0); - RUN_TEST_LOOP_c_c (cacos, cacos_test_data, ); - END_COMPLEX; + ALL_RM_TEST (cacos, 0, cacos_test_data, RUN_TEST_LOOP_c_c, END_COMPLEX); } static const struct test_c_c_data cacosh_test_data[] = diff --git a/math/s_cacos.c b/math/s_cacos.c index d0aaba4..2c22817 100644 --- a/math/s_cacos.c +++ b/math/s_cacos.c @@ -34,6 +34,8 @@ __cacos (__complex__ double x) y = __casin (x); __real__ res = (double) M_PI_2 - __real__ y; + if (__real__ res == 0.0) + __real__ res = 0.0; __imag__ res = -__imag__ y; } else diff --git a/math/s_cacosf.c b/math/s_cacosf.c index 9eaeeec..1c9d8b9 100644 --- a/math/s_cacosf.c +++ b/math/s_cacosf.c @@ -34,6 +34,8 @@ __cacosf (__complex__ float x) y = __casinf (x); __real__ res = (float) M_PI_2 - __real__ y; + if (__real__ res == 0.0f) + __real__ res = 0.0f; __imag__ res = -__imag__ y; } else diff --git a/math/s_cacosl.c b/math/s_cacosl.c index b9d3493..8688d3c 100644 --- a/math/s_cacosl.c +++ b/math/s_cacosl.c @@ -34,6 +34,8 @@ __cacosl (__complex__ long double x) y = __casinl (x); __real__ res = M_PI_2l - __real__ y; + if (__real__ res == 0.0L) + __real__ res = 0.0L; __imag__ res = -__imag__ y; } else diff --git a/sysdeps/i386/fpu/libm-test-ulps b/sysdeps/i386/fpu/libm-test-ulps index ccef44a..946cad4 100644 --- a/sysdeps/i386/fpu/libm-test-ulps +++ b/sysdeps/i386/fpu/libm-test-ulps @@ -173,6 +173,54 @@ ifloat: 1 ildouble: 2 ldouble: 2 +Function: Real part of "cacos_downward": +double: 2 +float: 1 +idouble: 2 +ifloat: 1 +ildouble: 2 +ldouble: 2 + +Function: Imaginary part of "cacos_downward": +double: 3 +float: 3 +idouble: 3 +ifloat: 3 +ildouble: 5 +ldouble: 5 + +Function: Real part of "cacos_towardzero": +double: 2 +float: 1 +idouble: 2 +ifloat: 1 +ildouble: 2 +ldouble: 2 + +Function: Imaginary part of "cacos_towardzero": +double: 3 +float: 3 +idouble: 3 +ifloat: 3 +ildouble: 5 +ldouble: 5 + +Function: Real part of "cacos_upward": +double: 2 +float: 2 +idouble: 2 +ifloat: 2 +ildouble: 2 +ldouble: 2 + +Function: Imaginary part of "cacos_upward": +double: 4 +float: 4 +idouble: 4 +ifloat: 4 +ildouble: 5 +ldouble: 5 + Function: Real part of "cacosh": double: 1 float: 1 diff --git a/sysdeps/x86_64/fpu/libm-test-ulps b/sysdeps/x86_64/fpu/libm-test-ulps index ad8ae9c..d472876 100644 --- a/sysdeps/x86_64/fpu/libm-test-ulps +++ b/sysdeps/x86_64/fpu/libm-test-ulps @@ -199,6 +199,54 @@ ifloat: 2 ildouble: 2 ldouble: 2 +Function: Real part of "cacos_downward": +double: 1 +float: 2 +idouble: 1 +ifloat: 2 +ildouble: 2 +ldouble: 2 + +Function: Imaginary part of "cacos_downward": +double: 5 +float: 3 +idouble: 5 +ifloat: 3 +ildouble: 5 +ldouble: 5 + +Function: Real part of "cacos_towardzero": +double: 1 +float: 2 +idouble: 1 +ifloat: 2 +ildouble: 2 +ldouble: 2 + +Function: Imaginary part of "cacos_towardzero": +double: 5 +float: 3 +idouble: 5 +ifloat: 3 +ildouble: 5 +ldouble: 5 + +Function: Real part of "cacos_upward": +double: 2 +float: 2 +idouble: 2 +ifloat: 2 +ildouble: 2 +ldouble: 2 + +Function: Imaginary part of "cacos_upward": +double: 4 +float: 4 +idouble: 4 +ifloat: 4 +ildouble: 5 +ldouble: 5 + Function: Real part of "cacosh": double: 1 float: 2 -- 2.7.4