aboutsummaryrefslogtreecommitdiff
path: root/sysdeps
diff options
context:
space:
mode:
authorJoseph Myers <joseph@codesourcery.com>2015-08-07 23:10:35 +0000
committerJoseph Myers <joseph@codesourcery.com>2015-08-07 23:10:35 +0000
commit37550cb3d6591a8f443467707ec80b4ab5c2e157 (patch)
tree934ef1da0ab3a2cd9d0a23b1645392914e95afcc /sysdeps
parentdb2bcbcb631f1c1aa023ef9f23a968e1ac288423 (diff)
downloadglibc-37550cb3d6591a8f443467707ec80b4ab5c2e157.zip
glibc-37550cb3d6591a8f443467707ec80b4ab5c2e157.tar.gz
glibc-37550cb3d6591a8f443467707ec80b4ab5c2e157.tar.bz2
Fix tan missing underflows (bug 16517).
Similar to various other bugs in this area, some tan implementations do not raise the underflow exception for subnormal arguments, when the result is tiny and inexact. This patch forces the exception in a similar way to previous fixes. Tested for x86_64, x86, mips64 and powerpc. [BZ #16517] * sysdeps/ieee754/dbl-64/s_tan.c: Include <float.h>. (tan): Force underflow exception for arguments with small absolute value. * sysdeps/ieee754/flt-32/k_tanf.c: Include <float.h>. (__kernel_tanf): Force underflow exception for arguments with small absolute value. * sysdeps/ieee754/ldbl-128/k_tanl.c: Include <float.h>. (__kernel_tanl): Force underflow exception for arguments with small absolute value. * sysdeps/ieee754/ldbl-128ibm/k_tanl.c: Include <float.h>. (__kernel_tanl): Force underflow exception for arguments with small absolute value. * sysdeps/ieee754/ldbl-96/k_tanl.c: Include <float.h>. (__kernel_tanl): Force underflow exception for arguments with small absolute value. * math/auto-libm-test-in: Add more tests of tan. * math/auto-libm-test-out: Regenerated.
Diffstat (limited to 'sysdeps')
-rw-r--r--sysdeps/ieee754/dbl-64/s_tan.c6
-rw-r--r--sysdeps/ieee754/flt-32/k_tanf.c13
-rw-r--r--sysdeps/ieee754/ldbl-128/k_tanl.c12
-rw-r--r--sysdeps/ieee754/ldbl-128ibm/k_tanl.c12
-rw-r--r--sysdeps/ieee754/ldbl-96/k_tanl.c12
5 files changed, 51 insertions, 4 deletions
diff --git a/sysdeps/ieee754/dbl-64/s_tan.c b/sysdeps/ieee754/dbl-64/s_tan.c
index dcb4aca..b4e3bd2 100644
--- a/sysdeps/ieee754/dbl-64/s_tan.c
+++ b/sysdeps/ieee754/dbl-64/s_tan.c
@@ -34,6 +34,7 @@
/*********************************************************************/
#include <errno.h>
+#include <float.h>
#include "endian.h"
#include <dla.h>
#include "mpa.h"
@@ -91,6 +92,11 @@ tan (double x)
/* (I) The case abs(x) <= 1.259e-8 */
if (w <= g1.d)
{
+ if (w < DBL_MIN)
+ {
+ double force_underflow = x * x;
+ math_force_eval (force_underflow);
+ }
retval = x;
goto ret;
}
diff --git a/sysdeps/ieee754/flt-32/k_tanf.c b/sysdeps/ieee754/flt-32/k_tanf.c
index a67f36e..2f2076d 100644
--- a/sysdeps/ieee754/flt-32/k_tanf.c
+++ b/sysdeps/ieee754/flt-32/k_tanf.c
@@ -17,6 +17,7 @@
static char rcsid[] = "$NetBSD: k_tanf.c,v 1.4 1995/05/10 20:46:39 jtc Exp $";
#endif
+#include <float.h>
#include <math.h>
#include <math_private.h>
static const float
@@ -48,7 +49,17 @@ float __kernel_tanf(float x, float y, int iy)
if(ix<0x39000000) /* x < 2**-13 */
{if((int)x==0) { /* generate inexact */
if((ix|(iy+1))==0) return one/fabsf(x);
- else return (iy==1)? x: -one/x;
+ else if (iy == 1)
+ {
+ if (fabsf (x) < FLT_MIN)
+ {
+ float force_underflow = x * x;
+ math_force_eval (force_underflow);
+ }
+ return x;
+ }
+ else
+ return -one / x;
}
}
if(ix>=0x3f2ca140) { /* |x|>=0.6744 */
diff --git a/sysdeps/ieee754/ldbl-128/k_tanl.c b/sysdeps/ieee754/ldbl-128/k_tanl.c
index dfba2d9..6a6fa9f 100644
--- a/sysdeps/ieee754/ldbl-128/k_tanl.c
+++ b/sysdeps/ieee754/ldbl-128/k_tanl.c
@@ -56,6 +56,7 @@
* = 1 - 2*(tan(y) - (tan(y)^2)/(1+tan(y)))
*/
+#include <float.h>
#include <libc-internal.h>
#include <math.h>
#include <math_private.h>
@@ -98,8 +99,17 @@ __kernel_tanl (long double x, long double y, int iy)
if ((ix | u.parts32.w1 | u.parts32.w2 | u.parts32.w3
| (iy + 1)) == 0)
return one / fabs (x);
+ else if (iy == 1)
+ {
+ if (fabsl (x) < LDBL_MIN)
+ {
+ long double force_underflow = x * x;
+ math_force_eval (force_underflow);
+ }
+ return x;
+ }
else
- return (iy == 1) ? x : -one / x;
+ return -one / x;
}
}
if (ix >= 0x3ffe5942) /* |x| >= 0.6743316650390625 */
diff --git a/sysdeps/ieee754/ldbl-128ibm/k_tanl.c b/sysdeps/ieee754/ldbl-128ibm/k_tanl.c
index 7f1caee..e50cc88 100644
--- a/sysdeps/ieee754/ldbl-128ibm/k_tanl.c
+++ b/sysdeps/ieee754/ldbl-128ibm/k_tanl.c
@@ -56,6 +56,7 @@
* = 1 - 2*(tan(y) - (tan(y)^2)/(1+tan(y)))
*/
+#include <float.h>
#include <libc-internal.h>
#include <math.h>
#include <math_private.h>
@@ -98,8 +99,17 @@ __kernel_tanl (long double x, long double y, int iy)
{
if ((ix | lx | (iy + 1)) == 0)
return one / fabs (x);
+ else if (iy == 1)
+ {
+ if (fabsl (x) < LDBL_MIN)
+ {
+ long double force_underflow = x * x;
+ math_force_eval (force_underflow);
+ }
+ return x;
+ }
else
- return (iy == 1) ? x : -one / x;
+ return -one / x;
}
}
if (ix >= 0x3fe59420) /* |x| >= 0.6743316650390625 */
diff --git a/sysdeps/ieee754/ldbl-96/k_tanl.c b/sysdeps/ieee754/ldbl-96/k_tanl.c
index 31cd236..ae6821d 100644
--- a/sysdeps/ieee754/ldbl-96/k_tanl.c
+++ b/sysdeps/ieee754/ldbl-96/k_tanl.c
@@ -56,6 +56,7 @@
* = 1 - 2*(tan(y) - (tan(y)^2)/(1+tan(y)))
*/
+#include <float.h>
#include <math.h>
#include <math_private.h>
static const long double
@@ -94,8 +95,17 @@ __kernel_tanl (long double x, long double y, int iy)
{ /* generate inexact */
if (x == 0 && iy == -1)
return one / fabsl (x);
+ else if (iy == 1)
+ {
+ if (absx < LDBL_MIN)
+ {
+ long double force_underflow = x * x;
+ math_force_eval (force_underflow);
+ }
+ return x;
+ }
else
- return (iy == 1) ? x : -one / x;
+ return -one / x;
}
}
if (absx >= 0.6743316650390625L)