diff options
Diffstat (limited to 'sysdeps/ieee754/dbl-64')
| -rw-r--r-- | sysdeps/ieee754/dbl-64/e_pow.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/sysdeps/ieee754/dbl-64/e_pow.c b/sysdeps/ieee754/dbl-64/e_pow.c index 3fd5e6507f..513171891c 100644 --- a/sysdeps/ieee754/dbl-64/e_pow.c +++ b/sysdeps/ieee754/dbl-64/e_pow.c @@ -90,6 +90,10 @@ __ieee754_pow(double x, double y) { SET_RESTORE_ROUND (FE_TONEAREST); + /* Avoid internal underflow for tiny y. The exact value of y does + not matter if |y| <= 2**-64. */ + if (ABS (y) < 0x1p-64) + y = y < 0 ? -0x1p-64 : 0x1p-64; z = log1(x,&aa,&error); /* x^y =e^(y log (X)) */ t = y*134217729.0; y1 = t - (t-y); |