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  • Committer: Package Import Robot
  • Author(s): Matthias Klose
  • Date: 2011-10-04 17:48:26 UTC
  • mfrom: (216.1.23 oneiric)
  • Revision ID: package-import@ubuntu.com-20111004174826-2cyb9ewn3ucymlsx
Tags: 2.13-20ubuntu5
https://launchpad.net/bugs/853688
libc6-dev: Don't break the current {gnat,gcj}-4.4-base versons. LP: #853688.

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sysdeps/ieee754/flt-32/e_sqrtf.c
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 *
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 * Developed at SunPro, a Sun Microsystems, Inc. business.
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 * Permission to use, copy, modify, and distribute this
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 * software is freely granted, provided that this notice
 
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 * software is freely granted, provided that this notice 
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 * is preserved.
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 * ====================================================
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 */
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#if defined(LIBM_SCCS) && !defined(lint)
 
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static char rcsid[] = "$NetBSD: e_sqrtf.c,v 1.4 1995/05/10 20:46:19 jtc Exp $";
 
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#endif
 
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#include "math.h"
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#include "math_private.h"
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#ifdef __STDC__
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static  const float     one     = 1.0, tiny=1.0e-30;
 
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#else
 
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static  float   one     = 1.0, tiny=1.0e-30;
 
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#endif
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float
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__ieee754_sqrtf(float x)
 
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#ifdef __STDC__
 
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        float __ieee754_sqrtf(float x)
 
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#else
 
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        float __ieee754_sqrtf(x)
 
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        float x;
 
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#endif
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{
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        float z;
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        int32_t sign = (int)0x80000000;
 
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        int32_t sign = (int)0x80000000; 
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        int32_t ix,s,q,m,t,i;
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        u_int32_t r;
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        GET_FLOAT_WORD(ix,x);
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    /* take care of Inf and NaN */
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        if((ix&0x7f800000)==0x7f800000) {
 
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        if((ix&0x7f800000)==0x7f800000) {                       
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            return x*x+x;               /* sqrt(NaN)=NaN, sqrt(+inf)=+inf
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                                           sqrt(-inf)=sNaN */
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        }
 
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        } 
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    /* take care of zero */
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        if(ix<=0) {
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            if((ix&(~sign))==0) return x;/* sqrt(+-0) = +-0 */
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        r = 0x01000000;         /* r = moving bit from right to left */
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        while(r!=0) {
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            t = s+r;
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            if(t<=ix) {
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                s    = t+r;
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                ix  -= t;
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                q   += r;
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            }
 
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            t = s+r; 
 
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            if(t<=ix) { 
 
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                s    = t+r; 
 
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                ix  -= t; 
 
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                q   += r; 
 
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            } 
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            ix += ix;
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            r>>=1;
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        }
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        if(ix!=0) {
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            z = one-tiny; /* trigger inexact flag */
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            if (z>=one) {
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                z = one+tiny;
 
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                z = one+tiny;
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                if (z>one)
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                    q += 2;
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                else
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        SET_FLOAT_WORD(z,ix);
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        return z;
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}
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strong_alias (__ieee754_sqrtf, __sqrtf_finite)