xref: /illumos-gate/usr/src/lib/libc/sparc/fp/_Q_cmp.c (revision 5d9d9091f564c198a760790b0bfa72c44e17912b)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright (c) 1994-1997, by Sun Microsystems, Inc.
24  * All rights reserved.
25  */
26 
27 #include "quad.h"
28 
29 #ifdef __sparcv9
30 #define	_Q_cmp	_Qp_cmp
31 #endif
32 
33 /*
34  * _Q_cmp(x, y) returns the condition code that would result from
35  * fcmpq *x, *y (and raises the same exceptions).
36  */
37 enum fcc_type
38 _Q_cmp(const union longdouble *x, const union longdouble *y)
39 {
40 	unsigned int	xm, ym, fsr;
41 
42 	if (QUAD_ISNAN(*x) || QUAD_ISNAN(*y)) {
43 		if ((QUAD_ISNAN(*x) && !(x->l.msw & 0x8000)) ||
44 		    (QUAD_ISNAN(*y) && !(y->l.msw & 0x8000))) {
45 			/* snan, signal invalid */
46 			__quad_getfsrp(&fsr);
47 			if (fsr & FSR_NVM) {
48 				__quad_fcmpq(x, y, &fsr);
49 				return ((fsr >> 10) & 3);
50 			} else {
51 				fsr = (fsr & ~FSR_CEXC) | FSR_NVA | FSR_NVC;
52 				__quad_setfsrp(&fsr);
53 			}
54 		}
55 		return (fcc_unordered);
56 	}
57 
58 	/* ignore sign of zero */
59 	xm = x->l.msw;
60 	if (QUAD_ISZERO(*x))
61 		xm &= 0x7fffffff;
62 	ym = y->l.msw;
63 	if (QUAD_ISZERO(*y))
64 		ym &= 0x7fffffff;
65 
66 	if ((xm ^ ym) & 0x80000000)	/* x and y have opposite signs */
67 		return ((ym & 0x80000000)? fcc_greater : fcc_less);
68 
69 	if (xm & 0x80000000) {
70 		if (xm > ym)
71 			return (fcc_less);
72 		if (xm < ym)
73 			return (fcc_greater);
74 		if (x->l.frac2 > y->l.frac2)
75 			return (fcc_less);
76 		if (x->l.frac2 < y->l.frac2)
77 			return (fcc_greater);
78 		if (x->l.frac3 > y->l.frac3)
79 			return (fcc_less);
80 		if (x->l.frac3 < y->l.frac3)
81 			return (fcc_greater);
82 		if (x->l.frac4 > y->l.frac4)
83 			return (fcc_less);
84 		if (x->l.frac4 < y->l.frac4)
85 			return (fcc_greater);
86 		return (fcc_equal);
87 	}
88 	if (xm < ym)
89 		return (fcc_less);
90 	if (xm > ym)
91 		return (fcc_greater);
92 	if (x->l.frac2 < y->l.frac2)
93 		return (fcc_less);
94 	if (x->l.frac2 > y->l.frac2)
95 		return (fcc_greater);
96 	if (x->l.frac3 < y->l.frac3)
97 		return (fcc_less);
98 	if (x->l.frac3 > y->l.frac3)
99 		return (fcc_greater);
100 	if (x->l.frac4 < y->l.frac4)
101 		return (fcc_less);
102 	if (x->l.frac4 > y->l.frac4)
103 		return (fcc_greater);
104 	return (fcc_equal);
105 }
106