2 /* @(#)s_floor.c 1.3 95/01/18 */
4 * ====================================================
5 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
7 * Developed at SunSoft, a Sun Microsystems, Inc. business.
8 * Permission to use, copy, modify, and distribute this
9 * software is freely granted, provided that this notice
11 * ====================================================
16 * Return x rounded toward -inf to integral value
20 * Inexact flag raised if x not equal to floor(x).
25 #ifndef _DOUBLE_IS_32BITS
28 static const double huge = 1.0e300;
30 static double huge = 1.0e300;
34 double floor(double x)
42 EXTRACT_WORDS(i0,i1,x);
43 j0 = ((i0>>20)&0x7ff)-0x3ff;
45 if(j0<0) { /* raise inexact if x != 0 */
46 if(huge+x>0.0) {/* return 0*sign(x) if |x|<1 */
48 else if(((i0&0x7fffffff)|i1)!=0)
49 { i0=0xbff00000;i1=0;}
53 if(((i0&i)|i1)==0) return x; /* x is integral */
54 if(huge+x>0.0) { /* raise inexact flag */
55 if(i0<0) i0 += (0x00100000)>>j0;
60 if(j0==0x400) return x+x; /* inf or NaN */
61 else return x; /* x is integral */
63 i = ((uint32_t)(0xffffffff))>>(j0-20);
64 if((i1&i)==0) return x; /* x is integral */
65 if(huge+x>0.0) { /* raise inexact flag */
70 if(j<(uint32_t)i1) i0 +=1 ; /* got a carry */
77 INSERT_WORDS(x,i0,i1);
80 #endif /* _DOUBLE_IS_32BITS */