83 lines
1.9 KiB
C
83 lines
1.9 KiB
C
/*
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* This file is part of the MicroPython project, http://micropython.org/
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*
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* These math functions are taken from newlib-nano-2, the newlib/libm/common
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* directory, available from https://github.com/32bitmicro/newlib-nano-2.
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*
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* Appropriate copyright headers are reproduced below.
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*/
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/* sf_modf.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 "fdlibm.h"
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#ifdef __STDC__
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static const float one = 1.0f;
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#else
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static float one = 1.0f;
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#endif
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#ifdef __STDC__
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float modff(float x, float *iptr)
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#else
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float modff(x, iptr)
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float x,*iptr;
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#endif
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{
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__int32_t i0,j0;
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__uint32_t i;
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GET_FLOAT_WORD(i0,x);
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j0 = ((i0>>23)&0xff)-0x7f; /* exponent of x */
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if(j0<23) { /* integer part in x */
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if(j0<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)>>j0;
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if((i0&i)==0) { /* x is integral */
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__uint32_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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__uint32_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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}
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#ifdef _DOUBLE_IS_32BITS
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#ifdef __STDC__
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double modf(double x, double *iptr)
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#else
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double modf(x, iptr)
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double x,*iptr;
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#endif
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{
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return (double) modff((float) x, (float *) iptr);
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}
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#endif /* defined(_DOUBLE_IS_32BITS) */
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