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| author | Joseph Myers <joseph@codesourcery.com> | 2015-06-23 22:24:20 +0000 |
|---|---|---|
| committer | Joseph Myers <joseph@codesourcery.com> | 2015-06-23 22:24:20 +0000 |
| commit | ad39cce0da0161dba69781c53349acf2e23f156c (patch) | |
| tree | 1c7b29a8fe9358aa720485ca439db53d6749b379 /sysdeps/ieee754/ldbl-96 | |
| parent | 8b1bab5ffa235bc494c33fdbe4c9994202936cfc (diff) | |
| download | glibc-ad39cce0da0161dba69781c53349acf2e23f156c.tar.gz glibc-ad39cce0da0161dba69781c53349acf2e23f156c.tar.xz glibc-ad39cce0da0161dba69781c53349acf2e23f156c.zip | |
Fix sin, sincos missing underflows (bug 16526, bug 16538).
Similar to various other bugs in this area, some sin and sincos 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 #16526] [BZ #16538] * sysdeps/ieee754/dbl-64/s_sin.c: Include <float.h>. (__sin): Force underflow exception for arguments with small absolute value. * sysdeps/ieee754/flt-32/k_sinf.c: Include <float.h>. (__kernel_sinf): Force underflow exception for arguments with small absolute value. * sysdeps/ieee754/ldbl-128/k_sincosl.c: Include <float.h>. (__kernel_sincosl): Force underflow exception for arguments with small absolute value. * sysdeps/ieee754/ldbl-128/k_sinl.c: Include <float.h>. (__kernel_sinl): Force underflow exception for arguments with small absolute value. * sysdeps/ieee754/ldbl-128ibm/k_sincosl.c: Include <float.h>. (__kernel_sincosl): Force underflow exception for arguments with small absolute value. * sysdeps/ieee754/ldbl-128ibm/k_sinl.c: Include <float.h>. (__kernel_sinl): Force underflow exception for arguments with small absolute value. * sysdeps/ieee754/ldbl-96/k_sinl.c: Include <float.h>. (__kernel_sinl): Force underflow exception for arguments with small absolute value. * sysdeps/powerpc/fpu/k_sinf.c: Include <float.h>. (__kernel_sinf): Force underflow exception for arguments with small absolute value. * math/auto-libm-test-in: Add more tests of sin and sincos. * math/auto-libm-test-out: Regenerated.
Diffstat (limited to 'sysdeps/ieee754/ldbl-96')
| -rw-r--r-- | sysdeps/ieee754/ldbl-96/k_sinl.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/sysdeps/ieee754/ldbl-96/k_sinl.c b/sysdeps/ieee754/ldbl-96/k_sinl.c index 179262a735..b7b5ae359d 100644 --- a/sysdeps/ieee754/ldbl-96/k_sinl.c +++ b/sysdeps/ieee754/ldbl-96/k_sinl.c @@ -20,6 +20,7 @@ /* The polynomials have not been optimized for extended-precision and may contain more terms than needed. */ +#include <float.h> #include <math.h> #include <math_private.h> @@ -94,7 +95,14 @@ __kernel_sinl(long double x, long double y, int iy) /* Argument is small enough to approximate it by a Chebyshev polynomial of degree 17. */ if (absx < 0x1p-33L) - if (!((int)x)) return x; /* generate inexact */ + { + if (fabsl (x) < LDBL_MIN) + { + long double force_underflow = x * x; + math_force_eval (force_underflow); + } + if (!((int)x)) return x; /* generate inexact */ + } z = x * x; return x + (x * (z*(SIN1+z*(SIN2+z*(SIN3+z*(SIN4+ z*(SIN5+z*(SIN6+z*(SIN7+z*SIN8))))))))); |