diff options
Diffstat (limited to 'sysdeps/ieee754')
| -rw-r--r-- | sysdeps/ieee754/flt-32/e_powf.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/sysdeps/ieee754/flt-32/e_powf.c b/sysdeps/ieee754/flt-32/e_powf.c index d0c912188f..965f1fc2e7 100644 --- a/sysdeps/ieee754/flt-32/e_powf.c +++ b/sysdeps/ieee754/flt-32/e_powf.c @@ -17,6 +17,8 @@ <http://www.gnu.org/licenses/>. */ #include <math.h> +#include <math-barriers.h> +#include <math-narrow-eval.h> #include <stdint.h> #include <shlib-compat.h> #include <libm-alias-float.h> @@ -207,7 +209,17 @@ __powf (float x, float y) { /* |y*log(x)| >= 126. */ if (ylogx > 0x1.fffffffd1d571p+6 * POWF_SCALE) + /* |x^y| > 0x1.ffffffp127. */ return __math_oflowf (sign_bias); + if (WANT_ROUNDING && WANT_ERRNO + && ylogx > 0x1.fffffffa3aae2p+6 * POWF_SCALE) + /* |x^y| > 0x1.fffffep127, check if we round away from 0. */ + if ((!sign_bias + && math_narrow_eval (1.0f + math_opt_barrier (0x1p-25f)) != 1.0f) + || (sign_bias + && math_narrow_eval (-1.0f - math_opt_barrier (0x1p-25f)) + != -1.0f)) + return __math_oflowf (sign_bias); if (ylogx <= -150.0 * POWF_SCALE) return __math_uflowf (sign_bias); #if WANT_ERRNO_UFLOW |