xref: /netbsd-src/external/gpl3/gcc.old/dist/libquadmath/math/ceilq.c (revision 627f7eb200a4419d89b531d55fccd2ee3ffdcde0)
1*627f7eb2Smrg /* s_ceill.c -- long double version of s_ceil.c.
2*627f7eb2Smrg  * Conversion to IEEE quad long double by Jakub Jelinek, jj@ultra.linux.cz.
3*627f7eb2Smrg  */
4*627f7eb2Smrg 
5*627f7eb2Smrg /*
6*627f7eb2Smrg  * ====================================================
7*627f7eb2Smrg  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
8*627f7eb2Smrg  *
9*627f7eb2Smrg  * Developed at SunPro, a Sun Microsystems, Inc. business.
10*627f7eb2Smrg  * Permission to use, copy, modify, and distribute this
11*627f7eb2Smrg  * software is freely granted, provided that this notice
12*627f7eb2Smrg  * is preserved.
13*627f7eb2Smrg  * ====================================================
14*627f7eb2Smrg  */
15*627f7eb2Smrg 
16*627f7eb2Smrg #if defined(LIBM_SCCS) && !defined(lint)
17*627f7eb2Smrg static char rcsid[] = "NetBSD: ";
18*627f7eb2Smrg #endif
19*627f7eb2Smrg 
20*627f7eb2Smrg /*
21*627f7eb2Smrg  * ceilq(x)
22*627f7eb2Smrg  * Return x rounded toward -inf to integral value
23*627f7eb2Smrg  * Method:
24*627f7eb2Smrg  *	Bit twiddling.
25*627f7eb2Smrg  */
26*627f7eb2Smrg 
27*627f7eb2Smrg #define NO_MATH_REDIRECT
28*627f7eb2Smrg 
29*627f7eb2Smrg #include "quadmath-imp.h"
30*627f7eb2Smrg 
ceilq(__float128 x)31*627f7eb2Smrg __float128 ceilq(__float128 x)
32*627f7eb2Smrg {
33*627f7eb2Smrg 	int64_t i0,i1,j0;
34*627f7eb2Smrg 	uint64_t i,j;
35*627f7eb2Smrg 	GET_FLT128_WORDS64(i0,i1,x);
36*627f7eb2Smrg 	j0 = ((i0>>48)&0x7fff)-0x3fff;
37*627f7eb2Smrg 	if(j0<48) {
38*627f7eb2Smrg 	    if(j0<0) {
39*627f7eb2Smrg 		/* return 0*sign(x) if |x|<1 */
40*627f7eb2Smrg 		if(i0<0) {i0=0x8000000000000000ULL;i1=0;}
41*627f7eb2Smrg 		else if((i0|i1)!=0) { i0=0x3fff000000000000ULL;i1=0;}
42*627f7eb2Smrg 	    } else {
43*627f7eb2Smrg 		i = (0x0000ffffffffffffULL)>>j0;
44*627f7eb2Smrg 		if(((i0&i)|i1)==0) return x; /* x is integral */
45*627f7eb2Smrg 		if(i0>0) i0 += (0x0001000000000000LL)>>j0;
46*627f7eb2Smrg 		i0 &= (~i); i1=0;
47*627f7eb2Smrg 	    }
48*627f7eb2Smrg 	} else if (j0>111) {
49*627f7eb2Smrg 	    if(j0==0x4000) return x+x;	/* inf or NaN */
50*627f7eb2Smrg 	    else return x;		/* x is integral */
51*627f7eb2Smrg 	} else {
52*627f7eb2Smrg 	    i = -1ULL>>(j0-48);
53*627f7eb2Smrg 	    if((i1&i)==0) return x;	/* x is integral */
54*627f7eb2Smrg 	    if(i0>0) {
55*627f7eb2Smrg 		if(j0==48) i0+=1;
56*627f7eb2Smrg 		else {
57*627f7eb2Smrg 		    j = i1+(1LL<<(112-j0));
58*627f7eb2Smrg 		    if(j<i1) i0 +=1 ; 	/* got a carry */
59*627f7eb2Smrg 		    i1=j;
60*627f7eb2Smrg 		}
61*627f7eb2Smrg 	    }
62*627f7eb2Smrg 	    i1 &= (~i);
63*627f7eb2Smrg 	}
64*627f7eb2Smrg 	SET_FLT128_WORDS64(x,i0,i1);
65*627f7eb2Smrg 	return x;
66*627f7eb2Smrg }
67