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/* s_modff.c -- float version of s_modf.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 one = 1.0; |
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float |
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modff(float x, float *iptr) |
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{ |
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int32_t i0,jj0; |
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u_int32_t i; |
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GET_FLOAT_WORD(i0,x); |
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jj0 = ((i0>>23)&0xff)-0x7f; /* exponent of x */ |
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if(jj0<23) { /* integer part in x */ |
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if(jj0<0) { /* |x|<1 */ |
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SET_FLOAT_WORD(*iptr,i0&0x80000000); /* *iptr = +-0 */ |
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return x; |
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} else { |
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i = (0x007fffff)>>jj0; |
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if((i0&i)==0) { /* x is integral */ |
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u_int32_t ix; |
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*iptr = x; |
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GET_FLOAT_WORD(ix,x); |
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SET_FLOAT_WORD(x,ix&0x80000000); /* return +-0 */ |
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return x; |
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} else { |
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SET_FLOAT_WORD(*iptr,i0&(~i)); |
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return x - *iptr; |
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} |
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} |
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} else { /* no fraction part */ |
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u_int32_t ix; |
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*iptr = x*one; |
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GET_FLOAT_WORD(ix,x); |
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SET_FLOAT_WORD(x,ix&0x80000000); /* return +-0 */ |
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return x; |
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} |
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} |