1 /* @(#)s_modf.c 5.1 93/09/24 */
3 * ====================================================
4 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
6 * Developed at SunPro, a Sun Microsystems, Inc. business.
7 * Permission to use, copy, modify, and distribute this
8 * software is freely granted, provided that this notice
10 * ====================================================
14 * modf(double x, double *iptr)
15 * return fraction part of x, and return x's integral part in *iptr.
24 #include "math_private.h"
26 static const double one = 1.0;
29 modf(double x, double *iptr)
33 EXTRACT_WORDS(i0,i1,x);
34 j0 = ((i0>>20)&0x7ff)-0x3ff; /* exponent of x */
35 if(j0<20) { /* integer part in high x */
36 if(j0<0) { /* |x|<1 */
37 INSERT_WORDS(*iptr,i0&0x80000000,0); /* *iptr = +-0 */
41 if(((i0&i)|i1)==0) { /* x is integral */
44 GET_HIGH_WORD(high,x);
45 INSERT_WORDS(x,high&0x80000000,0); /* return +-0 */
48 INSERT_WORDS(*iptr,i0&(~i),0);
52 } else if (j0>51) { /* no fraction part */
55 GET_HIGH_WORD(high,x);
56 INSERT_WORDS(x,high&0x80000000,0); /* return +-0 */
58 } else { /* fraction part in low x */
59 i = ((uint32_t)(0xffffffff))>>(j0-20);
60 if((i1&i)==0) { /* x is integral */
63 GET_HIGH_WORD(high,x);
64 INSERT_WORDS(x,high&0x80000000,0); /* return +-0 */
67 INSERT_WORDS(*iptr,i0,i1&(~i));