1 // Ceres Solver - A fast non-linear least squares minimizer
2 // Copyright 2015 Google Inc. All rights reserved.
3 // http://ceres-solver.org/
5 // Redistribution and use in source and binary forms, with or without
6 // modification, are permitted provided that the following conditions are met:
8 // * Redistributions of source code must retain the above copyright notice,
9 // this list of conditions and the following disclaimer.
10 // * Redistributions in binary form must reproduce the above copyright notice,
11 // this list of conditions and the following disclaimer in the documentation
12 // and/or other materials provided with the distribution.
13 // * Neither the name of Google Inc. nor the names of its contributors may be
14 // used to endorse or promote products derived from this software without
15 // specific prior written permission.
17 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
18 // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
21 // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22 // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23 // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24 // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25 // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26 // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27 // POSSIBILITY OF SUCH DAMAGE.
29 // Author: keir@google.com (Keir Mierle)
31 // Portable HashMap and HashSet, and a specialized overload for hashing pairs.
33 #ifndef CERES_INTERNAL_COLLECTIONS_PORT_H_
34 #define CERES_INTERNAL_COLLECTIONS_PORT_H_
36 #include "ceres/internal/port.h"
38 #if defined(CERES_NO_UNORDERED_MAP)
43 #if defined(CERES_TR1_UNORDERED_MAP)
44 # include <tr1/unordered_map>
45 # include <tr1/unordered_set>
46 # define CERES_HASH_NAMESPACE_START namespace std { namespace tr1 {
47 # define CERES_HASH_NAMESPACE_END } }
50 #if defined(CERES_STD_UNORDERED_MAP)
51 # include <unordered_map>
52 # include <unordered_set>
53 # define CERES_HASH_NAMESPACE_START namespace std {
54 # define CERES_HASH_NAMESPACE_END }
57 #if defined(CERES_STD_UNORDERED_MAP_IN_TR1_NAMESPACE)
58 # include <unordered_map>
59 # include <unordered_set>
60 # define CERES_HASH_NAMESPACE_START namespace std { namespace tr1 {
61 # define CERES_HASH_NAMESPACE_END } }
64 #if !defined(CERES_NO_UNORDERED_MAP) && !defined(CERES_TR1_UNORDERED_MAP) && \
65 !defined(CERES_STD_UNORDERED_MAP) && !defined(CERES_STD_UNORDERED_MAP_IN_TR1_NAMESPACE) // NOLINT
66 # error One of: CERES_NO_UNORDERED_MAP, CERES_TR1_UNORDERED_MAP,\
67 CERES_STD_UNORDERED_MAP, CERES_STD_UNORDERED_MAP_IN_TR1_NAMESPACE must be defined! // NOLINT
71 #include "ceres/integral_types.h"
73 // Some systems don't have access to unordered_map/unordered_set. In
74 // that case, substitute the hash map/set with normal map/set. The
75 // price to pay is slower speed for some operations.
76 #if defined(CERES_NO_UNORDERED_MAP)
81 template<typename K, typename V>
82 struct HashMap : map<K, V> {};
85 struct HashSet : set<K> {};
87 } // namespace internal
95 #if defined(CERES_TR1_UNORDERED_MAP) || \
96 defined(CERES_STD_UNORDERED_MAP_IN_TR1_NAMESPACE)
97 template<typename K, typename V>
98 struct HashMap : std::tr1::unordered_map<K, V> {};
100 struct HashSet : std::tr1::unordered_set<K> {};
103 #if defined(CERES_STD_UNORDERED_MAP)
104 template<typename K, typename V>
105 struct HashMap : std::unordered_map<K, V> {};
107 struct HashSet : std::unordered_set<K> {};
110 #if defined(_WIN32) && !defined(__MINGW64__) && !defined(__MINGW32__)
111 #define GG_LONGLONG(x) x##I64
112 #define GG_ULONGLONG(x) x##UI64
114 #define GG_LONGLONG(x) x##LL
115 #define GG_ULONGLONG(x) x##ULL
118 // The hash function is due to Bob Jenkins (see
119 // http://burtleburtle.net/bob/hash/index.html). Each mix takes 36 instructions,
120 // in 18 cycles if you're lucky. On x86 architectures, this requires 45
121 // instructions in 27 cycles, if you're lucky.
124 inline void hash_mix(uint32& a, uint32& b, uint32& c) {
125 a -= b; a -= c; a ^= (c>>13);
126 b -= c; b -= a; b ^= (a<<8);
127 c -= a; c -= b; c ^= (b>>13);
128 a -= b; a -= c; a ^= (c>>12);
129 b -= c; b -= a; b ^= (a<<16);
130 c -= a; c -= b; c ^= (b>>5);
131 a -= b; a -= c; a ^= (c>>3);
132 b -= c; b -= a; b ^= (a<<10);
133 c -= a; c -= b; c ^= (b>>15);
137 inline void hash_mix(uint64& a, uint64& b, uint64& c) {
138 a -= b; a -= c; a ^= (c>>43);
139 b -= c; b -= a; b ^= (a<<9);
140 c -= a; c -= b; c ^= (b>>8);
141 a -= b; a -= c; a ^= (c>>38);
142 b -= c; b -= a; b ^= (a<<23);
143 c -= a; c -= b; c ^= (b>>5);
144 a -= b; a -= c; a ^= (c>>35);
145 b -= c; b -= a; b ^= (a<<49);
146 c -= a; c -= b; c ^= (b>>11);
149 inline uint32 Hash32NumWithSeed(uint32 num, uint32 c) {
150 // The golden ratio; an arbitrary value.
151 uint32 b = 0x9e3779b9UL;
156 inline uint64 Hash64NumWithSeed(uint64 num, uint64 c) {
157 // More of the golden ratio.
158 uint64 b = GG_ULONGLONG(0xe08c1d668b756f82);
163 } // namespace internal
166 // Since on some platforms this is a doubly-nested namespace (std::tr1) and
167 // others it is not, the entire namespace line must be in a macro.
168 CERES_HASH_NAMESPACE_START
170 // The outrageously annoying specializations below are for portability reasons.
171 // In short, it's not possible to have two overloads of hash<pair<T1, T2>
173 // Hasher for STL pairs. Requires hashers for both members to be defined.
175 struct hash<pair<T, T> > {
176 size_t operator()(const pair<T, T>& p) const {
177 size_t h1 = hash<T>()(p.first);
178 size_t h2 = hash<T>()(p.second);
179 // The decision below is at compile time
180 return (sizeof(h1) <= sizeof(ceres::internal::uint32)) ?
181 ceres::internal::Hash32NumWithSeed(h1, h2) :
182 ceres::internal::Hash64NumWithSeed(h1, h2);
184 // Less than operator for MSVC.
185 bool operator()(const pair<T, T>& a,
186 const pair<T, T>& b) const {
189 static const size_t bucket_size = 4; // These are required by MSVC
190 static const size_t min_buckets = 8; // 4 and 8 are defaults.
193 CERES_HASH_NAMESPACE_END
195 #endif // CERES_NO_UNORDERED_MAP
196 #endif // CERES_INTERNAL_COLLECTIONS_PORT_H_