/* origin: FreeBSD /usr/src/lib/msun/src/s_nextafterf.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 "libm.h" float nextafterf(float x, float y) { volatile float t; int32_t hx,hy,ix,iy; GET_FLOAT_WORD(hx, x); GET_FLOAT_WORD(hy, y); ix = hx & 0x7fffffff; /* |x| */ iy = hy & 0x7fffffff; /* |y| */ if (ix > 0x7f800000 || /* x is nan */ iy > 0x7f800000) /* y is nan */ return x+y; if (x == y) /* x == y */ return y; if (ix == 0) { /* x == 0 */ SET_FLOAT_WORD(x, (hy&0x80000000)|1); /* return +-minsubnormal */ /* raise underflow flag */ t = x*x; if (t == x) return t; return x; } if (hx >= 0) { /* x > 0 */ if (hx > hy) { /* x > y, x -= ulp */ hx--; } else { /* x < y, x += ulp */ hx++; } } else { /* x < 0 */ if (hy >= 0 || hx > hy) { /* x < y, x -= ulp */ hx--; } else { /* x > y, x += ulp */ hx++; } } hy = hx & 0x7f800000; if (hy >= 0x7f800000) /* overflow */ return x+x; if (hy < 0x00800000) { /* underflow */ /* raise underflow flag */ t = x*x; if (t != x) { SET_FLOAT_WORD(y, hx); return y; } } SET_FLOAT_WORD(x, hx); return x; }