diff options
Diffstat (limited to 'sysdeps/libm-ieee754/s_tanh.c')
-rw-r--r-- | sysdeps/libm-ieee754/s_tanh.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/sysdeps/libm-ieee754/s_tanh.c b/sysdeps/libm-ieee754/s_tanh.c index 208b459b35..944f96386f 100644 --- a/sysdeps/libm-ieee754/s_tanh.c +++ b/sysdeps/libm-ieee754/s_tanh.c @@ -55,10 +55,10 @@ static double one=1.0, two=2.0, tiny = 1.0e-300; #endif { double t,z; - int32_t jx,ix; + int32_t jx,ix,lx; /* High word of |x|. */ - GET_HIGH_WORD(jx,x); + EXTRACT_WORDS(jx,lx,x); ix = jx&0x7fffffff; /* x is INF or NaN */ @@ -69,6 +69,8 @@ static double one=1.0, two=2.0, tiny = 1.0e-300; /* |x| < 22 */ if (ix < 0x40360000) { /* |x|<22 */ + if ((ix | lx) == 0) + return x; /* x == +-0 */ if (ix<0x3c800000) /* |x|<2**-55 */ return x*(one+x); /* tanh(small) = small */ if (ix>=0x3ff00000) { /* |x|>=1 */ |