1 /* @(#)s_floor.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 * ====================================================
15 * Return x rounded toward -inf to integral value
19 * Inexact flag raised if x not equal to floor(x).
23 #include "math_private.h"
25 static const double huge = 1.0e300;
32 EXTRACT_WORDS(i0,i1,x);
33 j0 = ((i0>>20)&0x7ff)-0x3ff;
35 if(j0<0) { /* raise inexact if x != 0 */
36 if(huge+x>0.0) {/* return 0*sign(x) if |x|<1 */
38 else if(((i0&0x7fffffff)|i1)!=0)
39 { i0=0xbff00000;i1=0;}
43 if(((i0&i)|i1)==0) return x; /* x is integral */
44 if(huge+x>0.0) { /* raise inexact flag */
45 if(i0<0) i0 += (0x00100000)>>j0;
50 if(j0==0x400) return x+x; /* inf or NaN */
51 else return x; /* x is integral */
53 i = ((uint32_t)(0xffffffff))>>(j0-20);
54 if((i1&i)==0) return x; /* x is integral */
55 if(huge+x>0.0) { /* raise inexact flag */
60 if(j<i1) i0 +=1 ; /* got a carry */
67 INSERT_WORDS(x,i0,i1);