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authorJoseph Myers <joseph@codesourcery.com>2014-05-14 12:37:24 +0000
committerJoseph Myers <joseph@codesourcery.com>2014-05-14 12:37:24 +0000
commit01dbacd22a8d5e0053f8d0cf13a80286b6cfe79b (patch)
tree91adc1f6c05cc5dbfb6b3b55b7500fa9dae9fd0e /math
parent913d03c864ea2547e97f8d2d30fc71a008d4d103 (diff)
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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.
Diffstat (limited to 'math')
-rw-r--r--math/libm-test.inc4
-rw-r--r--math/s_cacos.c2
-rw-r--r--math/s_cacosf.c2
-rw-r--r--math/s_cacosl.c2
4 files changed, 7 insertions, 3 deletions
diff --git a/math/libm-test.inc b/math/libm-test.inc
index b4177e8f8e..de7bc8ad94 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 d0aaba4e6a..2c22817d4d 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 9eaeeec53d..1c9d8b9186 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 b9d34930d6..8688d3cd36 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