summaryrefslogtreecommitdiff
path: root/lib/u64.h
blob: 1d581ecc713b7ca5ff35c0233408f4d79f030b0d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
/* uint64_t-like operations that work even on hosts lacking uint64_t

   Copyright (C) 2006 Free Software Foundation, Inc.

   This program is free software; you can redistribute it and/or modify it
   under the terms of the GNU General Public License as published by the
   Free Software Foundation; either version 2, or (at your option) any
   later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software Foundation,
   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */

/* Written by Paul Eggert.  */

#include <stddef.h>
#include <stdint.h>

/* Return X rotated left by N bits, where 0 < N < 64.  */
#define u64rol(x, n) u64or (u64shl (x, n), u64shr (x, 64 - n))

#ifdef UINT64_MAX

/* Native implementations are trivial.  See below for comments on what
   these operations do.  */
typedef uint64_t u64;
# define u64hilo(hi, lo) ((u64) (((u64) (hi) << 32) + (lo)))
# define u64init(hi, lo) u64hilo (hi, lo)
# define u64lo(x) ((u64) (x))
# define u64lt(x, y) ((x) < (y))
# define u64and(x, y) ((x) & (y))
# define u64or(x, y) ((x) | (y))
# define u64xor(x, y) ((x) ^ (y))
# define u64plus(x, y) ((x) + (y))
# define u64shl(x, n) ((x) << (n))
# define u64shr(x, n) ((x) >> (n))

#else

/* u64 is a 64-bit unsigned integer value.
   u64init (HI, LO), is like u64hilo (HI, LO), but for use in
   initializer contexts.  */
# ifdef WORDS_BIGENDIAN
typedef struct { uint32_t hi, lo; } u64;
#  define u64init(hi, lo) { hi, lo }
# else
typedef struct { uint32_t lo, hi; } u64;
#  define u64init(hi, lo) { lo, hi }
# endif

/* Given the high and low-order 32-bit quantities HI and LO, return a u64
   value representing (HI << 32) + LO.  */
static inline u64
u64hilo (uint32_t hi, uint32_t lo)
{
  u64 r;
  r.hi = hi;
  r.lo = lo;
  return r;
}

/* Return a u64 value representing LO.  */
static inline u64
u64lo (uint32_t lo)
{
  u64 r;
  r.hi = 0;
  r.lo = lo;
  return r;
}

/* Return X < Y.  */
static inline int
u64lt (u64 x, u64 y)
{
  return x.hi < y.hi || (x.hi == y.hi && x.lo < y.lo);
}

/* Return X & Y.  */
static inline u64
u64and (u64 x, u64 y)
{
  u64 r;
  r.hi = x.hi & y.hi;
  r.lo = x.lo & y.lo;
  return r;
}

/* Return X | Y.  */
static inline u64
u64or (u64 x, u64 y)
{
  u64 r;
  r.hi = x.hi | y.hi;
  r.lo = x.lo | y.lo;
  return r;
}

/* Return X ^ Y.  */
static inline u64
u64xor (u64 x, u64 y)
{
  u64 r;
  r.hi = x.hi ^ y.hi;
  r.lo = x.lo ^ y.lo;
  return r;
}

/* Return X + Y.  */
static inline u64
u64plus (u64 x, u64 y)
{
  u64 r;
  r.lo = x.lo + y.lo;
  r.hi = x.hi + y.hi + (r.lo < x.lo);
  return r;
}

/* Return X << N.  */
static inline u64
u64shl (u64 x, int n)
{
  u64 r;
  if (n < 32)
    {
      r.hi = (x.hi << n) | (x.lo >> (32 - n));
      r.lo = x.lo << n;
    }
  else
    {
      r.hi = x.lo << (n - 32);
      r.lo = 0;
    }
  return r;
}

/* Return X >> N.  */
static inline u64
u64shr (u64 x, int n)
{
  u64 r;
  if (n < 32)
    {
      r.hi = x.hi >> n;
      r.lo = (x.hi << (32 - n)) | (x.lo >> n);
    }
  else
    {
      r.hi = 0;
      r.lo = x.hi >> (n - 32);
    }
  return r;
}

#endif