diff options
Diffstat (limited to 'sysdeps/libm-ieee754/s_logbf.c')
| -rw-r--r-- | sysdeps/libm-ieee754/s_logbf.c | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/sysdeps/libm-ieee754/s_logbf.c b/sysdeps/libm-ieee754/s_logbf.c new file mode 100644 index 0000000000..ade892a8f9 --- /dev/null +++ b/sysdeps/libm-ieee754/s_logbf.c @@ -0,0 +1,40 @@ +/* s_logbf.c -- float version of s_logb.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. + * ==================================================== + */ + +#if defined(LIBM_SCCS) && !defined(lint) +static char rcsid[] = "$NetBSD: s_logbf.c,v 1.4 1995/05/10 20:47:51 jtc Exp $"; +#endif + +#include "math.h" +#include "math_private.h" + +#ifdef __STDC__ + float __logbf(float x) +#else + float __logbf(x) + float x; +#endif +{ + int32_t ix; + GET_FLOAT_WORD(ix,x); + ix &= 0x7fffffff; /* high |x| */ + if(ix==0) return (float)-1.0/fabsf(x); + if(ix>=0x7f800000) return x*x; + if((ix>>=23)==0) /* IEEE 754 logb */ + return -126.0; + else + return (float) (ix-127); +} +weak_alias (__logbf, logbf) |