| /* 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) |
