diff options
Diffstat (limited to 'sysdeps/ieee754/dbl-64/s_fmaf.c')
-rw-r--r-- | sysdeps/ieee754/dbl-64/s_fmaf.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/sysdeps/ieee754/dbl-64/s_fmaf.c b/sysdeps/ieee754/dbl-64/s_fmaf.c index e7a0650f0f..a4f12d9f76 100644 --- a/sysdeps/ieee754/dbl-64/s_fmaf.c +++ b/sysdeps/ieee754/dbl-64/s_fmaf.c @@ -32,8 +32,15 @@ float __fmaf (float x, float y, float z) { fenv_t env; + /* Multiplication is always exact. */ double temp = (double) x * (double) y; + + /* Ensure correct sign of an exact zero result by performing the + addition in the original rounding mode in that case. */ + if (temp == -z) + return (float) temp + z; + union ieee754_double u; libc_feholdexcept_setround (&env, FE_TOWARDZERO); |