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/* s_scalbnf.c -- float version of s_scalbn.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.
* ====================================================
*/
#include "fdlibm.h"
static const float
two25 = 3.355443200e+07, /* 0x4c000000 */
twom25 = 2.9802322388e-08; /* 0x33000000 */
float
scalblnf (float x, long int n)
{
__int32_t ix;
uint32_t hx;
long int k;
GET_FLOAT_WORD(ix,x);
hx = ix&0x7fffffff;
k = hx>>23; /* extract exponent */
if (k==0) { /* 0 or subnormal x */
if (hx == 0) return x; /* +-0 */
x *= two25;
GET_FLOAT_WORD(ix,x);
k = ((ix&0x7f800000)>>23) - 25;
if (n< -50000)
return __math_uflowf(ix<0); /*underflow*/
}
if (k==0xff) return x+x; /* NaN or Inf */
k = k+n;
if (n> 50000 || k > 0xfe)
return __math_oflowf(ix < 0); /* overflow */
if (k > 0) /* normal result */
{SET_FLOAT_WORD(x,(ix&0x807fffff)|(k<<23)); return x;}
if (k <= -25)
return __math_uflowf(ix < 0); /*underflow*/
k += 25; /* subnormal result */
SET_FLOAT_WORD(x,(ix&0x807fffff)|(k<<23));
return check_uflowf(x*twom25);
}
_MATH_ALIAS_f_fj(scalbln)
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