diff options
Diffstat (limited to 'libm/s_isinf.c')
| -rw-r--r-- | libm/s_isinf.c | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/libm/s_isinf.c b/libm/s_isinf.c new file mode 100644 index 000000000..ce509f072 --- /dev/null +++ b/libm/s_isinf.c @@ -0,0 +1,34 @@ +/* + * Written by J.T. Conklin <jtc@netbsd.org>. + * Changed to return -1 for -Inf by Ulrich Drepper <drepper@cygnus.com>. + * Public domain. + */ + +#if defined(LIBM_SCCS) && !defined(lint) +static char rcsid[] = "$NetBSD: s_isinf.c,v 1.3 1995/05/11 23:20:14 jtc Exp $"; +#endif + +/* + * isinf(x) returns 1 is x is inf, -1 if x is -inf, else 0; + * no branching! + */ + +#include "math.h" +#include "math_private.h" + +libm_hidden_proto(__isinf) +int +__isinf (double x) +{ + int32_t hx,lx; + EXTRACT_WORDS(hx,lx,x); + lx |= (hx & 0x7fffffff) ^ 0x7ff00000; + lx |= -lx; + return ~(lx >> 31) & (hx >> 30); +} +libm_hidden_def (__isinf) +weak_alias (__isinf, isinf) +#ifdef NO_LONG_DOUBLE +strong_alias (__isinf, __isinfl) +weak_alias (__isinf, isinfl) +#endif |