diff options
Diffstat (limited to 'math/s_csqrtl.c')
| -rw-r--r-- | math/s_csqrtl.c | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/math/s_csqrtl.c b/math/s_csqrtl.c index de23f8d85d..10988ba6ac 100644 --- a/math/s_csqrtl.c +++ b/math/s_csqrtl.c @@ -118,12 +118,28 @@ __csqrtl (__complex__ long double x) if (__real__ x > 0) { r = __ieee754_sqrtl (0.5L * (d + __real__ x)); - s = 0.5L * (__imag__ x / r); + if (scale == 1 && fabsl (__imag__ x) < 1.0L) + { + /* Avoid possible intermediate underflow. */ + s = __imag__ x / r; + r = __scalbnl (r, scale); + scale = 0; + } + else + s = 0.5L * (__imag__ x / r); } else { s = __ieee754_sqrtl (0.5L * (d - __real__ x)); - r = fabsl (0.5L * (__imag__ x / s)); + if (scale == 1 && fabsl (__imag__ x) < 1.0L) + { + /* Avoid possible intermediate underflow. */ + r = fabsl (__imag__ x / s); + s = __scalbnl (s, scale); + scale = 0; + } + else + r = fabsl (0.5L * (__imag__ x / s)); } if (scale) |