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// Ceres Solver - A fast non-linear least squares minimizer
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// Copyright 2010, 2011, 2012 Google Inc. All rights reserved.
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// http://code.google.com/p/ceres-solver/
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// Redistribution and use in source and binary forms, with or without
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// modification, are permitted provided that the following conditions are met:
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// * Redistributions of source code must retain the above copyright notice,
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// this list of conditions and the following disclaimer.
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// * Redistributions in binary form must reproduce the above copyright notice,
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// this list of conditions and the following disclaimer in the documentation
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// and/or other materials provided with the distribution.
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// * Neither the name of Google Inc. nor the names of its contributors may be
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// used to endorse or promote products derived from this software without
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// specific prior written permission.
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
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// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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// POSSIBILITY OF SUCH DAMAGE.
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// Author: keir@google.com (Keir Mierle)
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// Portable HashMap and HashSet, and a specialized overload for hashing pairs.
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#ifndef CERES_INTERNAL_COLLECTIONS_PORT_H_
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#define CERES_INTERNAL_COLLECTIONS_PORT_H_
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#include <tr1/unordered_map>
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#include <tr1/unordered_set>
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#include "ceres/integral_types.h"
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#include "ceres/internal/port.h"
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template<typename K, typename V>
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struct HashMap : tr1::unordered_map<K, V> {};
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struct HashSet : tr1::unordered_set<K> {};
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#define GG_LONGLONG(x) x##I64
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#define GG_ULONGLONG(x) x##UI64
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#define GG_LONGLONG(x) x##LL
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#define GG_ULONGLONG(x) x##ULL
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// The hash function is due to Bob Jenkins (see
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// http://burtleburtle.net/bob/hash/index.html). Each mix takes 36 instructions,
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// in 18 cycles if you're lucky. On x86 architectures, this requires 45
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// instructions in 27 cycles, if you're lucky.
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inline void hash_mix(uint32& a, uint32& b, uint32& c) {
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a -= b; a -= c; a ^= (c>>13);
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b -= c; b -= a; b ^= (a<<8);
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c -= a; c -= b; c ^= (b>>13);
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a -= b; a -= c; a ^= (c>>12);
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b -= c; b -= a; b ^= (a<<16);
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c -= a; c -= b; c ^= (b>>5);
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a -= b; a -= c; a ^= (c>>3);
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b -= c; b -= a; b ^= (a<<10);
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c -= a; c -= b; c ^= (b>>15);
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inline void hash_mix(uint64& a, uint64& b, uint64& c) {
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a -= b; a -= c; a ^= (c>>43);
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b -= c; b -= a; b ^= (a<<9);
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c -= a; c -= b; c ^= (b>>8);
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a -= b; a -= c; a ^= (c>>38);
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b -= c; b -= a; b ^= (a<<23);
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c -= a; c -= b; c ^= (b>>5);
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a -= b; a -= c; a ^= (c>>35);
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b -= c; b -= a; b ^= (a<<49);
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c -= a; c -= b; c ^= (b>>11);
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inline uint32 Hash32NumWithSeed(uint32 num, uint32 c) {
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// The golden ratio; an arbitrary value.
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uint32 b = 0x9e3779b9UL;
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inline uint64 Hash64NumWithSeed(uint64 num, uint64 c) {
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// More of the golden ratio.
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uint64 b = GG_ULONGLONG(0xe08c1d668b756f82);
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} // namespace internal
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// Since on some platforms this is a doubly-nested namespace (std::tr1) and
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// others it is not, the entire namespace line must be in a macro.
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CERES_HASH_NAMESPACE_START
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// The outrageously annoying specializations below are for portability reasons.
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// In short, it's not possible to have two overloads of hash<pair<T1, T2>
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// Hasher for STL pairs. Requires hashers for both members to be defined.
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struct hash<pair<T, T> > {
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size_t operator()(const pair<T, T>& p) const {
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size_t h1 = hash<T>()(p.first);
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size_t h2 = hash<T>()(p.second);
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// The decision below is at compile time
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return (sizeof(h1) <= sizeof(ceres::internal::uint32)) ?
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ceres::internal::Hash32NumWithSeed(h1, h2) :
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ceres::internal::Hash64NumWithSeed(h1, h2);
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// Less than operator for MSVC.
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bool operator()(const pair<T, T>& a,
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const pair<T, T>& b) const {
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static const size_t bucket_size = 4; // These are required by MSVC
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static const size_t min_buckets = 8; // 4 and 8 are defaults.
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CERES_HASH_NAMESPACE_END
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#endif // CERES_INTERNAL_COLLECTIONS_PORT_H_
added
removed
internal/ceres/collections_port.h
