/* sf_floor.c -- float version of s_floor.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. * ==================================================== */ /* * floorf(x) * Return x rounded toward -inf to integral value * Method: * Bit twiddling. * Exception: * Inexact flag raised if x not equal to floorf(x). */ #include "fdlibm.h" float floorf(float x) { __int32_t i0, j0; __uint32_t i, ix; GET_FLOAT_WORD(i0, x); ix = (i0 & 0x7fffffff); j0 = (ix >> 23) - 0x7f; if (j0 < 23) { if (j0 < 0) { /* raise inexact if x != 0 */ if (i0 >= 0) { i0 = 0; } else if (!FLT_UWORD_IS_ZERO(ix)) { i0 = 0xbf800000; } } else { i = (0x007fffff) >> j0; if ((i0 & i) == 0) return x; /* x is integral */ if (i0 < 0) i0 += (0x00800000) >> j0; i0 &= (~i); } } else { if (!FLT_UWORD_IS_FINITE(ix)) return x + x; /* inf or NaN */ else return x; /* x is integral */ } SET_FLOAT_WORD(x, i0); return x; } _MATH_ALIAS_f_f(floor)