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authorJoseph Myers <joseph@codesourcery.com>2014-04-02 17:41:02 +0000
committerJoseph Myers <joseph@codesourcery.com>2014-04-02 17:41:02 +0000
commita84e78c8b3c4de94b488fdc5321f71feeb99358f (patch)
treeb4e8a63fd2eb10f4598a5af855e6462a9b06767e /math
parent6f05bafebac30a389807979f8efbb709f84b486f (diff)
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Fix catan, catanh, __ieee754_logf in round-downward mode (bug 16799, bug 16800).
This patch fixes incorrect results from catan and catanh of certain special inputs in round-downward mode (bug 16799), and incorrect results of __ieee754_logf (+/-0) in round-downward mode (bug 16800) that show up through catan/catanh when tested in all rounding modes, but not directly in the testing for logf because the bug gets hidden by the wrappers. Both bugs involve a zero that should be +0 being -0 instead: one computed as (1-x)*(1+x) in the catan/catanh case, and one as (x-x) in the logf case. The fixes ensure positive zero is used. Testing of catan and catanh in all rounding modes is duly enabled. I expect there are various other bugs in special cases in __ieee754_* functions that are normally hidden by the wrappers but would show up for testing with -lieee (or in future with -fno-math-errno if we replace -lieee and _LIB_VERSION with compile-time redirection to new *_noerrno symbol names). Tested x86_64 and x86 and ulps updated accordingly. [BZ #16799] [BZ #16800] * math/s_catan.c (__catan): Avoid passing -0 denominator to atan2 with 0 numerator. * math/s_catanf.c (__catanf): Likewise. * math/s_catanh.c (__catanh): Likewise. * math/s_catanhf.c (__catanhf): Likewise. * math/s_catanhl.c (__catanhl): Likewise. * math/s_catanl.c (__catanl): Likewise. * sysdeps/ieee754/flt-32/e_logf.c (__ieee754_logf): Always divide by positive zero when computing -Inf result. * math/libm-test.inc (catan_test): Use ALL_RM_TEST. (catanh_test): Likewise. * 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.inc8
-rw-r--r--math/s_catan.c6
-rw-r--r--math/s_catanf.c6
-rw-r--r--math/s_catanh.c6
-rw-r--r--math/s_catanhf.c6
-rw-r--r--math/s_catanhl.c6
-rw-r--r--math/s_catanl.c6
7 files changed, 32 insertions, 12 deletions
diff --git a/math/libm-test.inc b/math/libm-test.inc
index c6279e7..5e6789f 100644
--- a/math/libm-test.inc
+++ b/math/libm-test.inc
@@ -5239,9 +5239,7 @@ static const struct test_c_c_data catan_test_data[] =
static void
catan_test (void)
{
- START (catan, 0);
- RUN_TEST_LOOP_c_c (catan, catan_test_data, );
- END_COMPLEX;
+ ALL_RM_TEST (catan, 0, catan_test_data, RUN_TEST_LOOP_c_c, END_COMPLEX);
}
static const struct test_c_c_data catanh_test_data[] =
@@ -5746,9 +5744,7 @@ static const struct test_c_c_data catanh_test_data[] =
static void
catanh_test (void)
{
- START (catanh, 0);
- RUN_TEST_LOOP_c_c (catanh, catanh_test_data, );
- END_COMPLEX;
+ ALL_RM_TEST (catanh, 0, catanh_test_data, RUN_TEST_LOOP_c_c, END_COMPLEX);
}
static const struct test_f_f_data cbrt_test_data[] =
diff --git a/math/s_catan.c b/math/s_catan.c
index d6552d8..0cfa924 100644
--- a/math/s_catan.c
+++ b/math/s_catan.c
@@ -89,7 +89,11 @@ __catan (__complex__ double x)
}
if (absy < DBL_EPSILON / 2.0)
- den = (1.0 - absx) * (1.0 + absx);
+ {
+ den = (1.0 - absx) * (1.0 + absx);
+ if (den == -0.0)
+ den = 0.0;
+ }
else if (absx >= 1.0)
den = (1.0 - absx) * (1.0 + absx) - absy * absy;
else if (absx >= 0.75 || absy >= 0.5)
diff --git a/math/s_catanf.c b/math/s_catanf.c
index 41e419d..b478684 100644
--- a/math/s_catanf.c
+++ b/math/s_catanf.c
@@ -90,7 +90,11 @@ __catanf (__complex__ float x)
}
if (absy < FLT_EPSILON / 2.0f)
- den = (1.0f - absx) * (1.0f + absx);
+ {
+ den = (1.0f - absx) * (1.0f + absx);
+ if (den == -0.0f)
+ den = 0.0f;
+ }
else if (absx >= 1.0f)
den = (1.0f - absx) * (1.0f + absx) - absy * absy;
else if (absx >= 0.75f || absy >= 0.5f)
diff --git a/math/s_catanh.c b/math/s_catanh.c
index 2ba1298..7ef9142 100644
--- a/math/s_catanh.c
+++ b/math/s_catanh.c
@@ -110,7 +110,11 @@ __catanh (__complex__ double x)
}
if (absy < DBL_EPSILON / 2.0)
- den = (1.0 - absx) * (1.0 + absx);
+ {
+ den = (1.0 - absx) * (1.0 + absx);
+ if (den == -0.0)
+ den = 0.0;
+ }
else if (absx >= 1.0)
den = (1.0 - absx) * (1.0 + absx) - absy * absy;
else if (absx >= 0.75 || absy >= 0.5)
diff --git a/math/s_catanhf.c b/math/s_catanhf.c
index 0ee69a5..0e55aff 100644
--- a/math/s_catanhf.c
+++ b/math/s_catanhf.c
@@ -112,7 +112,11 @@ __catanhf (__complex__ float x)
}
if (absy < FLT_EPSILON / 2.0f)
- den = (1.0f - absx) * (1.0f + absx);
+ {
+ den = (1.0f - absx) * (1.0f + absx);
+ if (den == -0.0f)
+ den = 0.0f;
+ }
else if (absx >= 1.0f)
den = (1.0f - absx) * (1.0f + absx) - absy * absy;
else if (absx >= 0.75f || absy >= 0.5f)
diff --git a/math/s_catanhl.c b/math/s_catanhl.c
index 537bb3e..6410afe 100644
--- a/math/s_catanhl.c
+++ b/math/s_catanhl.c
@@ -118,7 +118,11 @@ __catanhl (__complex__ long double x)
}
if (absy < LDBL_EPSILON / 2.0L)
- den = (1.0L - absx) * (1.0L + absx);
+ {
+ den = (1.0L - absx) * (1.0L + absx);
+ if (den == -0.0L)
+ den = 0.0L;
+ }
else if (absx >= 1.0L)
den = (1.0L - absx) * (1.0L + absx) - absy * absy;
else if (absx >= 0.75L || absy >= 0.5L)
diff --git a/math/s_catanl.c b/math/s_catanl.c
index cea9282..dd01d16 100644
--- a/math/s_catanl.c
+++ b/math/s_catanl.c
@@ -97,7 +97,11 @@ __catanl (__complex__ long double x)
}
if (absy < LDBL_EPSILON / 2.0L)
- den = (1.0L - absx) * (1.0L + absx);
+ {
+ den = (1.0L - absx) * (1.0L + absx);
+ if (den == -0.0L)
+ den = 0.0L;
+ }
else if (absx >= 1.0L)
den = (1.0L - absx) * (1.0L + absx) - absy * absy;
else if (absx >= 0.75L || absy >= 0.5L)