xref: /illumos-gate/usr/src/lib/libc/port/fp/quadint.h (revision f37b3cbb6f67aaea5eec1c335bdc7bf432867d64)
1 /*
2  * Copyright (c) 1992, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This software was developed by the Computer Systems Engineering group
6  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
7  * contributed to Berkeley.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *	This product includes software developed by the University of
20  *	California, Berkeley and its contributors.
21  * 4. Neither the name of the University nor the names of its contributors
22  *    may be used to endorse or promote products derived from this software
23  *    without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  *
37  *	@(#)quad.h	8.1 (Berkeley) 6/4/93
38  */
39 
40 /*
41  * Quad arithmetic.
42  *
43  * This library makes the following assumptions:
44  *
45  *  - The type long long aka longlong_t exists.
46  *
47  *  - A quad variable is exactly twice as long as `long'.
48  *
49  *  - The machine's arithmetic is two's complement.
50  *
51  * This library can provide 128-bit arithmetic on a machine with 128-bit
52  * quads and 64-bit longs, for instance, or 96-bit arithmetic on machines
53  * with 48-bit longs.
54  */
55 
56 #ifndef __QUADINT_H
57 #define	__QUADINT_H
58 
59 #include <sys/isa_defs.h>
60 #include <sys/types.h>
61 #include <limits.h>
62 
63 #ifdef __cplusplus
64 extern "C" {
65 #endif
66 
67 /*
68  * Define the order of 32-bit words in 64-bit words.
69  */
70 #ifdef _LONG_LONG_LTOH
71 #define	_QUAD_HIGHWORD 1
72 #define	_QUAD_LOWWORD 0
73 #else
74 #define	_QUAD_HIGHWORD 0
75 #define	_QUAD_LOWWORD 1
76 #endif
77 
78 /*
79  * Depending on the desired operation, we view a `long long' in
80  * one or more of the following formats.
81  */
82 union uu {
83 	longlong_t	q;		/* as a (signed) quad */
84 	u_longlong_t	uq;		/* as an unsigned quad */
85 	long		sl[2];		/* as two signed longs */
86 	ulong_t		ul[2];		/* as two unsigned longs */
87 };
88 
89 /*
90  * Define high and low longwords.
91  */
92 #define	H		_QUAD_HIGHWORD
93 #define	L		_QUAD_LOWWORD
94 
95 /*
96  * Total number of bits in a longlong_t and in the pieces that make it up.
97  * These are used for shifting, and also below for halfword extraction
98  * and assembly.
99  */
100 #define	QUAD_BITS	(sizeof (u_longlong_t) * CHAR_BIT)
101 #define	LONG_BITS	(sizeof (long) * CHAR_BIT)
102 #define	HALF_BITS	(sizeof (long) * CHAR_BIT / 2)
103 
104 /*
105  * Extract high and low shortwords from longword, and move low shortword of
106  * longword to upper half of long, i.e., produce the upper longword of
107  * ((longlong_t)(x) << (number_of_bits_in_long/2)).
108  * (`x' must actually be ulong_t.)
109  *
110  * These are used in the multiply code, to split a longword into upper
111  * and lower halves, and to reassemble a product as a longlong_t, shifted left
112  * (sizeof(long)*CHAR_BIT/2).
113  */
114 #define	HHALF(x)	((x) >> HALF_BITS)
115 #define	LHALF(x)	((x) & ((1 << HALF_BITS) - 1))
116 #define	LHUP(x)		((x) << HALF_BITS)
117 
118 longlong_t	___divdi3(longlong_t a, longlong_t b);
119 longlong_t	___moddi3(longlong_t a, longlong_t b);
120 u_longlong_t	___qdivrem(u_longlong_t u, u_longlong_t v, u_longlong_t *rem);
121 u_longlong_t	___udivdi3(u_longlong_t a, u_longlong_t b);
122 u_longlong_t	___umoddi3(u_longlong_t a, u_longlong_t b);
123 
124 typedef unsigned int	qshift_t;
125 
126 #ifdef __cplusplus
127 }
128 #endif
129 
130 #endif	/* !__QUADINT_H */
131