12116Sjkh/* s_scalbnf.c -- float version of s_scalbn.c. 22116Sjkh * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. 32116Sjkh */ 42116Sjkh 52116Sjkh/* 62116Sjkh * ==================================================== 72116Sjkh * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 82116Sjkh * 92116Sjkh * Developed at SunPro, a Sun Microsystems, Inc. business. 102116Sjkh * Permission to use, copy, modify, and distribute this 118870Srgrimes * software is freely granted, provided that this notice 122116Sjkh * is preserved. 132116Sjkh * ==================================================== 142116Sjkh */ 152116Sjkh 162116Sjkh#ifndef lint 1750476Speterstatic char rcsid[] = "$FreeBSD$"; 182116Sjkh#endif 192116Sjkh 20143205Sdas#include <sys/cdefs.h> 21143205Sdas 222116Sjkh#include "math.h" 232116Sjkh#include "math_private.h" 242116Sjkh 252116Sjkhstatic const float 262116Sjkhtwo25 = 3.355443200e+07, /* 0x4c000000 */ 272116Sjkhtwom25 = 2.9802322388e-08, /* 0x33000000 */ 282116Sjkhhuge = 1.0e+30, 292116Sjkhtiny = 1.0e-30; 302116Sjkh 3197413Salfredfloat 3297413Salfredscalbnf (float x, int n) 332116Sjkh{ 342116Sjkh int32_t k,ix; 352116Sjkh GET_FLOAT_WORD(ix,x); 362116Sjkh k = (ix&0x7f800000)>>23; /* extract exponent */ 372116Sjkh if (k==0) { /* 0 or subnormal x */ 382116Sjkh if ((ix&0x7fffffff)==0) return x; /* +-0 */ 392116Sjkh x *= two25; 402116Sjkh GET_FLOAT_WORD(ix,x); 418870Srgrimes k = ((ix&0x7f800000)>>23) - 25; 422116Sjkh if (n< -50000) return tiny*x; /*underflow*/ 432116Sjkh } 442116Sjkh if (k==0xff) return x+x; /* NaN or Inf */ 458870Srgrimes k = k+n; 462116Sjkh if (k > 0xfe) return huge*copysignf(huge,x); /* overflow */ 472116Sjkh if (k > 0) /* normal result */ 482116Sjkh {SET_FLOAT_WORD(x,(ix&0x807fffff)|(k<<23)); return x;} 492116Sjkh if (k <= -25) 502116Sjkh if (n > 50000) /* in case integer overflow in n+k */ 512116Sjkh return huge*copysignf(huge,x); /*overflow*/ 522116Sjkh else return tiny*copysignf(tiny,x); /*underflow*/ 532116Sjkh k += 25; /* subnormal result */ 542116Sjkh SET_FLOAT_WORD(x,(ix&0x807fffff)|(k<<23)); 552116Sjkh return x*twom25; 562116Sjkh} 57143205Sdas 58143205Sdas__strong_reference(scalbnf, ldexpf); 59