diff options
Diffstat (limited to 'math/s_csqrtf.c')
| -rw-r--r-- | math/s_csqrtf.c | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/math/s_csqrtf.c b/math/s_csqrtf.c index c9a800e8aa..7f45cc1320 100644 --- a/math/s_csqrtf.c +++ b/math/s_csqrtf.c @@ -118,12 +118,28 @@ __csqrtf (__complex__ float x) if (__real__ x > 0) { r = __ieee754_sqrtf (0.5f * (d + __real__ x)); - s = 0.5f * (__imag__ x / r); + if (scale == 1 && fabsf (__imag__ x) < 1.0f) + { + /* Avoid possible intermediate underflow. */ + s = __imag__ x / r; + r = __scalbnf (r, scale); + scale = 0; + } + else + s = 0.5f * (__imag__ x / r); } else { s = __ieee754_sqrtf (0.5f * (d - __real__ x)); - r = fabsf (0.5f * (__imag__ x / s)); + if (scale == 1 && fabsf (__imag__ x) < 1.0f) + { + /* Avoid possible intermediate underflow. */ + r = fabsf (__imag__ x / s); + s = __scalbnf (s, scale); + scale = 0; + } + else + r = fabsf (0.5f * (__imag__ x / s)); } if (scale) |