diff options
Diffstat (limited to 'libc/math/sf_isnan.c')
| -rw-r--r-- | libc/math/sf_isnan.c | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/libc/math/sf_isnan.c b/libc/math/sf_isnan.c new file mode 100644 index 0000000..8fdb6ad --- /dev/null +++ b/libc/math/sf_isnan.c @@ -0,0 +1,49 @@ +/* sf_isnan.c -- float version of s_isnan.c. + * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. + */ + +/* + * ==================================================== + * 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. + * ==================================================== + */ + +/* + * isnanf(x) returns 1 is x is nan, else 0; + * no branching! + */ + +#include "fdlibm.h" + +#ifdef __STDC__ + int isnanf(float x) +#else + int isnanf(x) + float x; +#endif +{ + __int32_t ix; + GET_FLOAT_WORD(ix,x); + ix &= 0x7fffffff; + ix = 0x7f800000 - ix; + return (int)(((__uint32_t)(ix))>>31); +} + +#ifdef _DOUBLE_IS_32BITS + +#ifdef __STDC__ + int isnan(double x) +#else + int isnan(x) + double x; +#endif +{ + return isnanf((float) x); +} + +#endif /* defined(_DOUBLE_IS_32BITS) */ |