1/* uint64_t-like operations that work even on hosts lacking uint64_t
2
3   Copyright (C) 2006, 2009, 2010 Free Software Foundation, Inc.
4
5   This program is free software: you can redistribute it and/or modify
6   it under the terms of the GNU General Public License as published by
7   the Free Software Foundation, either version 3 of the License, or
8   (at your option) any later version.
9
10   This program is distributed in the hope that it will be useful,
11   but WITHOUT ANY WARRANTY; without even the implied warranty of
12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13   GNU General Public License for more details.
14
15   You should have received a copy of the GNU General Public License
16   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
17
18/* Written by Paul Eggert.  */
19
20#include <stddef.h>
21#include <stdint.h>
22
23/* Return X rotated left by N bits, where 0 < N < 64.  */
24#define u64rol(x, n) u64or (u64shl (x, n), u64shr (x, 64 - n))
25
26#ifdef UINT64_MAX
27
28/* Native implementations are trivial.  See below for comments on what
29   these operations do.  */
30typedef uint64_t u64;
31# define u64hilo(hi, lo) ((u64) (((u64) (hi) << 32) + (lo)))
32# define u64init(hi, lo) u64hilo (hi, lo)
33# define u64lo(x) ((u64) (x))
34# define u64lt(x, y) ((x) < (y))
35# define u64and(x, y) ((x) & (y))
36# define u64or(x, y) ((x) | (y))
37# define u64xor(x, y) ((x) ^ (y))
38# define u64plus(x, y) ((x) + (y))
39# define u64shl(x, n) ((x) << (n))
40# define u64shr(x, n) ((x) >> (n))
41
42#else
43
44/* u64 is a 64-bit unsigned integer value.
45   u64init (HI, LO), is like u64hilo (HI, LO), but for use in
46   initializer contexts.  */
47# ifdef WORDS_BIGENDIAN
48typedef struct { uint32_t hi, lo; } u64;
49#  define u64init(hi, lo) { hi, lo }
50# else
51typedef struct { uint32_t lo, hi; } u64;
52#  define u64init(hi, lo) { lo, hi }
53# endif
54
55/* Given the high and low-order 32-bit quantities HI and LO, return a u64
56   value representing (HI << 32) + LO.  */
57static inline u64
58u64hilo (uint32_t hi, uint32_t lo)
59{
60  u64 r;
61  r.hi = hi;
62  r.lo = lo;
63  return r;
64}
65
66/* Return a u64 value representing LO.  */
67static inline u64
68u64lo (uint32_t lo)
69{
70  u64 r;
71  r.hi = 0;
72  r.lo = lo;
73  return r;
74}
75
76/* Return X < Y.  */
77static inline int
78u64lt (u64 x, u64 y)
79{
80  return x.hi < y.hi || (x.hi == y.hi && x.lo < y.lo);
81}
82
83/* Return X & Y.  */
84static inline u64
85u64and (u64 x, u64 y)
86{
87  u64 r;
88  r.hi = x.hi & y.hi;
89  r.lo = x.lo & y.lo;
90  return r;
91}
92
93/* Return X | Y.  */
94static inline u64
95u64or (u64 x, u64 y)
96{
97  u64 r;
98  r.hi = x.hi | y.hi;
99  r.lo = x.lo | y.lo;
100  return r;
101}
102
103/* Return X ^ Y.  */
104static inline u64
105u64xor (u64 x, u64 y)
106{
107  u64 r;
108  r.hi = x.hi ^ y.hi;
109  r.lo = x.lo ^ y.lo;
110  return r;
111}
112
113/* Return X + Y.  */
114static inline u64
115u64plus (u64 x, u64 y)
116{
117  u64 r;
118  r.lo = x.lo + y.lo;
119  r.hi = x.hi + y.hi + (r.lo < x.lo);
120  return r;
121}
122
123/* Return X << N.  */
124static inline u64
125u64shl (u64 x, int n)
126{
127  u64 r;
128  if (n < 32)
129    {
130      r.hi = (x.hi << n) | (x.lo >> (32 - n));
131      r.lo = x.lo << n;
132    }
133  else
134    {
135      r.hi = x.lo << (n - 32);
136      r.lo = 0;
137    }
138  return r;
139}
140
141/* Return X >> N.  */
142static inline u64
143u64shr (u64 x, int n)
144{
145  u64 r;
146  if (n < 32)
147    {
148      r.hi = x.hi >> n;
149      r.lo = (x.hi << (32 - n)) | (x.lo >> n);
150    }
151  else
152    {
153      r.hi = 0;
154      r.lo = x.hi >> (n - 32);
155    }
156  return r;
157}
158
159#endif
160