1/*	$OpenBSD: fixsfdi.c,v 1.1 2022/09/03 08:26:05 mbuhl Exp $	*/
2/*	$NetBSD: fixsfdi_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: fixsfdi_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 <stdbool.h>
49#include <machine/ieee.h>
50
51/*
52 * Convert float to signed quad.
53 */
54quad_t
55__fixsfdi(float x)
56{
57	struct ieee_single ux = *(struct ieee_single *)&x;
58	signed int exp = ux.sng_exp - SNG_EXP_BIAS;
59	const bool neg = ux.sng_sign;
60	quad_t r;
61
62	if (exp < 0)
63		return 0;
64	if (exp > 62)
65		return neg ? QUAD_MIN : QUAD_MAX;
66
67	r = 1 << SNG_FRACBITS;		/* implicit bit */
68	r |= ux.sng_frac;
69	exp -= SNG_FRACBITS;
70	if (exp < 0) {
71		r >>= -exp;
72	} else if (exp > 0) {
73		r <<= exp;
74	}
75	return neg ? -r : r;
76}
77