/* * This file is part of the MicroPython project, http://micropython.org/ * * These math functions are taken from newlib-nano-2, the newlib/libm/math * directory, available from https://github.com/32bitmicro/newlib-nano-2. * * Appropriate copyright headers are reproduced below. */ /* sf_frexp.c -- float version of s_frexp.c. * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. */ /* * ==================================================== * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. * * Developed at SunPro, a Sun Microsystems, Inc. business. * Permission to use, copy, modify, and distribute this * software is freely granted, provided that this notice * is preserved. * ==================================================== */ #include "fdlibm.h" #ifdef __STDC__ static const float #else static float #endif two25 = 3.3554432000e+07; /* 0x4c000000 */ #ifdef __STDC__ float frexpf(float x, int *eptr) #else float frexpf(x, eptr) float x; int *eptr; #endif { __int32_t hx, ix; GET_FLOAT_WORD(hx,x); ix = 0x7fffffff&hx; *eptr = 0; if(!FLT_UWORD_IS_FINITE(ix)||FLT_UWORD_IS_ZERO(ix)) return x; /* 0,inf,nan */ if (FLT_UWORD_IS_SUBNORMAL(ix)) { /* subnormal */ x *= two25; GET_FLOAT_WORD(hx,x); ix = hx&0x7fffffff; *eptr = -25; } *eptr += (ix>>23)-126; hx = (hx&0x807fffff)|0x3f000000; SET_FLOAT_WORD(x,hx); return x; } #ifdef _DOUBLE_IS_32BITS #ifdef __STDC__ double frexp(double x, int *eptr) #else double frexp(x, eptr) double x; int *eptr; #endif { return (double) frexpf((float) x, eptr); } #endif /* defined(_DOUBLE_IS_32BITS) */