diff options
Diffstat (limited to 'libm/s_isnan.c')
| -rw-r--r-- | libm/s_isnan.c | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/libm/s_isnan.c b/libm/s_isnan.c new file mode 100644 index 000000000..1bc49cb02 --- /dev/null +++ b/libm/s_isnan.c @@ -0,0 +1,29 @@ +/* + * ==================================================== + * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. + * + * Developed at SunPro, a Sun Microsystems, Inc. business. + * Permission to use, copy, modify, and distribute this + * software is freely granted, provided that this notice + * is preserved. + * ==================================================== + */ + +/* + * isnan(x) returns 1 is x is nan, else 0; + * no branching! + */ + +#include "math.h" +#include "math_private.h" + +int __isnan(double x) +{ + int32_t hx,lx; + EXTRACT_WORDS(hx,lx,x); + hx &= 0x7fffffff; + hx |= (u_int32_t)(lx|(-lx))>>31; + hx = 0x7ff00000 - hx; + return (int)(((u_int32_t)hx)>>31); +} +libm_hidden_def(__isnan) |