1/*-
2 * Copyright (c) 1990 The Regents of the University of California.
3 * All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Sean Eric Fagan.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 4. Neither the name of the University nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33#if defined(LIBC_SCCS) && !defined(lint)
34	.asciz "@(#)modf.s	5.5 (Berkeley) 3/18/91"
35#endif /* LIBC_SCCS and not lint */
36#include <machine/asm.h>
37__FBSDID("$FreeBSD$");
38
39/*
40 * modf(value, iptr): return fractional part of value, and stores the
41 * integral part into iptr (a pointer to double).
42 *
43 * Written by Sean Eric Fagan (sef@kithrup.COM)
44 * Sun Mar 11 20:27:30 PST 1990
45 */
46
47/* With CHOP mode on, frndint behaves as TRUNC does.  Useful. */
48
49ENTRY(modf)
50	pushl %ebp
51	movl %esp,%ebp
52	/* Check for Inf/NaN */
53	movl 12(%ebp),%eax
54	andl $0x7fffffff,%eax
55	cmpl $0x7ff00000,%eax
56	jae 1f
57	/* Finite value */
58	subl $16,%esp
59	fnstcw -12(%ebp)
60	movw -12(%ebp),%dx
61	orw $3072,%dx
62	movw %dx,-16(%ebp)
63	fldcw -16(%ebp)
64	fldl 8(%ebp)
65	frndint
66	fstpl -8(%ebp)
67	fldcw -12(%ebp)
68	movl 16(%ebp),%eax
69	movl -8(%ebp),%edx
70	movl -4(%ebp),%ecx
71	movl %edx,(%eax)
72	movl %ecx,4(%eax)
73	fldl 8(%ebp)
74	fsubl -8(%ebp)
75	leave
76	ret
77	/* Inf/NaN handling */
781:	fldl 8(%ebp)
79	movl 16(%ebp),%edx
80	fstl (%edx)
81	fldz
82	fdivp	/* return +/- 0 for +/- Inf, NaN for NaN */
83	leave
84	ret
85END(modf)
86
87	.section .note.GNU-stack,"",%progbits
88