xref: /openbsd/lib/libc/arch/arm/quad/fixunssfdi.c (revision 5dea098c)
1 /*	$OpenBSD: fixunssfdi.c,v 1.1 2022/09/03 08:26:05 mbuhl Exp $	*/
2 /*	$NetBSD: fixunssfdi_ieee754.c,v 1.1 2013/08/24 00:51:48 matt Exp $	*/
3 
4 /*-
5  * Copyright (c) 1992, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * This software was developed by the Computer Systems Engineering group
9  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
10  * contributed to Berkeley.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #include <sys/cdefs.h>
38 #if defined(LIBC_SCCS) && !defined(lint)
39 __RCSID("$NetBSD: fixunssfdi_ieee754.c,v 1.1 2013/08/24 00:51:48 matt Exp $");
40 #endif /* LIBC_SCCS and not lint */
41 
42 #if defined(SOFTFLOAT) || defined(__ARM_EABI__)
43 #include "softfloat/softfloat-for-gcc.h"
44 #endif
45 
46 #include "../../../quad/quad.h"
47 #include <limits.h>
48 #include <machine/ieee.h>
49 
50 /*
51  * Convert float to unsigned quad.
52  * Not sure what to do with negative numbers---for now, anything out
53  * of range becomes UQUAD_MAX.
54  */
55 u_quad_t
56 __fixunssfdi(float x)
57 {
58 	struct ieee_single ux = *(struct ieee_single *)&x;
59 	signed int exp = ux.sng_exp - SNG_EXP_BIAS;
60 	u_quad_t r;
61 
62 	if (ux.sng_sign)
63 		return UQUAD_MAX;
64 	if (exp > 63)
65 		return UQUAD_MAX;
66 	if (exp < 0)
67 		return 0;
68 
69 	r = 1 << SNG_FRACBITS;		/* implicit bit */
70 	r |= ux.sng_frac;
71 	exp -= SNG_FRACBITS;
72 	if (exp == 0)
73 		return r;
74 	if (exp < 0)
75 		return r >> -exp;
76 
77 	return r << exp;
78 }
79