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/* s_frexpf.c -- float version of s_frexp.c. |
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* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. |
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*/ |
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/* |
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* ==================================================== |
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* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
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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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* is preserved. |
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* ==================================================== |
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*/ |
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#include "math.h" |
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#include "math_private.h" |
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static const float |
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two25 = 3.3554432000e+07; /* 0x4c000000 */ |
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float |
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frexpf(float x, int *eptr) |
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{ |
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int32_t hx,ix; |
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GET_FLOAT_WORD(hx,x); |
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ix = 0x7fffffff&hx; |
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*eptr = 0; |
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if(ix>=0x7f800000||(ix==0)) return x; /* 0,inf,nan */ |
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if (ix<0x00800000) { /* subnormal */ |
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x *= two25; |
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GET_FLOAT_WORD(hx,x); |
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ix = hx&0x7fffffff; |
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*eptr = -25; |
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} |
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*eptr += (ix>>23)-126; |
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hx = (hx&0x807fffff)|0x3f000000; |
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SET_FLOAT_WORD(x,hx); |
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return x; |
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} |