/* origin: FreeBSD /usr/src/lib/msun/src/s_truncf.c */ /* * ==================================================== * 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. * ==================================================== */ /* * truncf(x) * Return x rounded toward 0 to integral value * Method: * Bit twiddling. * Exception: * Inexact flag raised if x not equal to truncf(x). */ #include "libm.h" static const float huge = 1.0e30f; float truncf(float x) { int32_t i0,j0; uint32_t i; GET_FLOAT_WORD(i0, x); j0 = ((i0>>23)&0xff) - 0x7f; if (j0 < 23) { if (j0 < 0) { /* |x|<1, return 0*sign(x) */ /* raise inexact if x != 0 */ if (huge+x > 0.0f) i0 &= 0x80000000; } else { i = 0x007fffff>>j0; if ((i0&i) == 0) return x; /* x is integral */ /* raise inexact */ if (huge+x > 0.0f) i0 &= ~i; } } else { if (j0 == 0x80) return x + x; /* inf or NaN */ return x; /* x is integral */ } SET_FLOAT_WORD(x, i0); return x; }