sysdeps/libm-ieee754/w_scalbf.c

   1 /* w_scalbf.c -- float version of w_scalb.c.
   2  * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
   3  */
   4
   5 /*
   6  * ====================================================
   7  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
   8  *
   9  * Developed at SunPro, a Sun Microsystems, Inc. business.
  10  * Permission to use, copy, modify, and distribute this
  11  * software is freely granted, provided that this notice
  12  * is preserved.
  13  * ====================================================
  14  */
  15
  16 #if defined(LIBM_SCCS) && !defined(lint)
  17 static char rcsid[] = "$NetBSD: w_scalbf.c,v 1.3 1995/05/10 20:49:50 jtc Exp $";
  18 #endif
  19
  20 /*
  21  * wrapper scalbf(float x, float fn) is provide for
  22  * passing various standard test suite. One
  23  * should use scalbn() instead.
  24  */
  25
  26 #include "math.h"
  27 #include "math_private.h"
  28
  29 #include <errno.h>
  30
  31 #ifdef __STDC__
  32 #ifdef _SCALB_INT
  33         float __scalbf(float x, int fn)         /* wrapper scalbf */
  34 #else
  35         float __scalbf(float x, float fn)               /* wrapper scalbf */
  36 #endif
  37 #else
  38         float __scalbf(x,fn)                    /* wrapper scalbf */
  39 #ifdef _SCALB_INT
  40         float x; int fn;
  41 #else
  42         float x,fn;
  43 #endif
  44 #endif
  45 {
  46 #ifdef _IEEE_LIBM
  47         return __ieee754_scalbf(x,fn);
  48 #else
  49         float z;
  50         z = __ieee754_scalbf(x,fn);
  51         if(_LIB_VERSION == _IEEE_) return z;
  52         if(!(__finitef(z)||__isnanf(z))&&__finitef(x)) {
  53             /* scalbf overflow */
  54             return (float)__kernel_standard((double)x,(double)fn,132);
  55         }
  56         if(z==(float)0.0&&z!=x) {
  57             /* scalbf underflow */
  58             return (float)__kernel_standard((double)x,(double)fn,133);
  59         }
  60 #ifndef _SCALB_INT
  61         if(!__finitef(fn)) errno = ERANGE;
  62 #endif
  63         return z;
  64 #endif
  65 }
  66 weak_alias (__scalbf, scalbf)