Eigen  3.4.90 (git rev a4098ac676528a83cfb73d4d26ce1b42ec05f47c)
Ref.h
1// This file is part of Eigen, a lightweight C++ template library
2// for linear algebra.
3//
4// Copyright (C) 2012 Gael Guennebaud <gael.guennebaud@inria.fr>
5//
6// This Source Code Form is subject to the terms of the Mozilla
7// Public License v. 2.0. If a copy of the MPL was not distributed
8// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
9
10#ifndef EIGEN_REF_H
11#define EIGEN_REF_H
12
13#include "./InternalHeaderCheck.h"
14
15namespace Eigen {
16
17namespace internal {
18
19template<typename _PlainObjectType, int Options_, typename _StrideType>
20struct traits<Ref<_PlainObjectType, Options_, _StrideType> >
21 : public traits<Map<_PlainObjectType, Options_, _StrideType> >
22{
23 typedef _PlainObjectType PlainObjectType;
24 typedef _StrideType StrideType;
25 enum {
26 Options = Options_,
27 Flags = traits<Map<_PlainObjectType, Options_, _StrideType> >::Flags | NestByRefBit,
28 Alignment = traits<Map<_PlainObjectType, Options_, _StrideType> >::Alignment
29 };
30
31 template<typename Derived> struct match {
32 enum {
33 IsVectorAtCompileTime = PlainObjectType::IsVectorAtCompileTime || Derived::IsVectorAtCompileTime,
34 HasDirectAccess = internal::has_direct_access<Derived>::ret,
35 StorageOrderMatch = IsVectorAtCompileTime || ((PlainObjectType::Flags&RowMajorBit)==(Derived::Flags&RowMajorBit)),
36 InnerStrideMatch = int(StrideType::InnerStrideAtCompileTime)==int(Dynamic)
37 || int(StrideType::InnerStrideAtCompileTime)==int(Derived::InnerStrideAtCompileTime)
38 || (int(StrideType::InnerStrideAtCompileTime)==0 && int(Derived::InnerStrideAtCompileTime)==1),
39 OuterStrideMatch = IsVectorAtCompileTime
40 || int(StrideType::OuterStrideAtCompileTime)==int(Dynamic) || int(StrideType::OuterStrideAtCompileTime)==int(Derived::OuterStrideAtCompileTime),
41 // NOTE, this indirection of evaluator<Derived>::Alignment is needed
42 // to workaround a very strange bug in MSVC related to the instantiation
43 // of has_*ary_operator in evaluator<CwiseNullaryOp>.
44 // This line is surprisingly very sensitive. For instance, simply adding parenthesis
45 // as "DerivedAlignment = (int(evaluator<Derived>::Alignment))," will make MSVC fail...
46 DerivedAlignment = int(evaluator<Derived>::Alignment),
47 AlignmentMatch = (int(traits<PlainObjectType>::Alignment)==int(Unaligned)) || (DerivedAlignment >= int(Alignment)), // FIXME the first condition is not very clear, it should be replaced by the required alignment
48 ScalarTypeMatch = internal::is_same<typename PlainObjectType::Scalar, typename Derived::Scalar>::value,
49 MatchAtCompileTime = HasDirectAccess && StorageOrderMatch && InnerStrideMatch && OuterStrideMatch && AlignmentMatch && ScalarTypeMatch
50 };
51 typedef typename internal::conditional<MatchAtCompileTime,internal::true_type,internal::false_type>::type type;
52 };
53
54};
55
56template<typename Derived>
57struct traits<RefBase<Derived> > : public traits<Derived> {};
58
59}
60
61template<typename Derived> class RefBase
62 : public MapBase<Derived>
63{
64 typedef typename internal::traits<Derived>::PlainObjectType PlainObjectType;
65 typedef typename internal::traits<Derived>::StrideType StrideType;
66
67public:
68
69 typedef MapBase<Derived> Base;
70 EIGEN_DENSE_PUBLIC_INTERFACE(RefBase)
71
72 EIGEN_DEVICE_FUNC EIGEN_CONSTEXPR inline Index innerStride() const
73 {
74 return StrideType::InnerStrideAtCompileTime != 0 ? m_stride.inner() : 1;
75 }
76
77 EIGEN_DEVICE_FUNC EIGEN_CONSTEXPR inline Index outerStride() const
78 {
79 return StrideType::OuterStrideAtCompileTime != 0 ? m_stride.outer()
80 : IsVectorAtCompileTime ? this->size()
81 : int(Flags)&RowMajorBit ? this->cols()
82 : this->rows();
83 }
84
85 EIGEN_DEVICE_FUNC RefBase()
86 : Base(0,RowsAtCompileTime==Dynamic?0:RowsAtCompileTime,ColsAtCompileTime==Dynamic?0:ColsAtCompileTime),
87 // Stride<> does not allow default ctor for Dynamic strides, so let' initialize it with dummy values:
88 m_stride(StrideType::OuterStrideAtCompileTime==Dynamic?0:StrideType::OuterStrideAtCompileTime,
89 StrideType::InnerStrideAtCompileTime==Dynamic?0:StrideType::InnerStrideAtCompileTime)
90 {}
91
92 EIGEN_INHERIT_ASSIGNMENT_OPERATORS(RefBase)
93
94protected:
95
96 typedef Stride<StrideType::OuterStrideAtCompileTime,StrideType::InnerStrideAtCompileTime> StrideBase;
97
98 // Resolves inner stride if default 0.
99 static EIGEN_DEVICE_FUNC EIGEN_CONSTEXPR Index resolveInnerStride(Index inner) {
100 return inner == 0 ? 1 : inner;
101 }
102
103 // Resolves outer stride if default 0.
104 static EIGEN_DEVICE_FUNC EIGEN_CONSTEXPR Index resolveOuterStride(Index inner, Index outer, Index rows, Index cols, bool isVectorAtCompileTime, bool isRowMajor) {
105 return outer == 0 ? isVectorAtCompileTime ? inner * rows * cols : isRowMajor ? inner * cols : inner * rows : outer;
106 }
107
108 // Returns true if construction is valid, false if there is a stride mismatch,
109 // and fails if there is a size mismatch.
110 template<typename Expression>
111 EIGEN_DEVICE_FUNC bool construct(Expression& expr)
112 {
113 // Check matrix sizes. If this is a compile-time vector, we do allow
114 // implicitly transposing.
115 EIGEN_STATIC_ASSERT(
116 EIGEN_PREDICATE_SAME_MATRIX_SIZE(PlainObjectType, Expression)
117 // If it is a vector, the transpose sizes might match.
118 || ( PlainObjectType::IsVectorAtCompileTime
119 && ((int(PlainObjectType::RowsAtCompileTime)==Eigen::Dynamic
120 || int(Expression::ColsAtCompileTime)==Eigen::Dynamic
121 || int(PlainObjectType::RowsAtCompileTime)==int(Expression::ColsAtCompileTime))
122 && (int(PlainObjectType::ColsAtCompileTime)==Eigen::Dynamic
123 || int(Expression::RowsAtCompileTime)==Eigen::Dynamic
124 || int(PlainObjectType::ColsAtCompileTime)==int(Expression::RowsAtCompileTime)))),
125 YOU_MIXED_MATRICES_OF_DIFFERENT_SIZES
126 )
127
128 // Determine runtime rows and columns.
129 Index rows = expr.rows();
130 Index cols = expr.cols();
131 if(PlainObjectType::RowsAtCompileTime==1)
132 {
133 eigen_assert(expr.rows()==1 || expr.cols()==1);
134 rows = 1;
135 cols = expr.size();
136 }
137 else if(PlainObjectType::ColsAtCompileTime==1)
138 {
139 eigen_assert(expr.rows()==1 || expr.cols()==1);
140 rows = expr.size();
141 cols = 1;
142 }
143 // Verify that the sizes are valid.
144 eigen_assert(
145 (PlainObjectType::RowsAtCompileTime == Dynamic) || (PlainObjectType::RowsAtCompileTime == rows));
146 eigen_assert(
147 (PlainObjectType::ColsAtCompileTime == Dynamic) || (PlainObjectType::ColsAtCompileTime == cols));
148
149
150 // If this is a vector, we might be transposing, which means that stride should swap.
151 const bool transpose = PlainObjectType::IsVectorAtCompileTime && (rows != expr.rows());
152 // If the storage format differs, we also need to swap the stride.
153 const bool row_major = ((PlainObjectType::Flags)&RowMajorBit) != 0;
154 const bool expr_row_major = (Expression::Flags&RowMajorBit) != 0;
155 const bool storage_differs = (row_major != expr_row_major);
156
157 const bool swap_stride = (transpose != storage_differs);
158
159 // Determine expr's actual strides, resolving any defaults if zero.
160 const Index expr_inner_actual = resolveInnerStride(expr.innerStride());
161 const Index expr_outer_actual = resolveOuterStride(expr_inner_actual,
162 expr.outerStride(),
163 expr.rows(),
164 expr.cols(),
165 Expression::IsVectorAtCompileTime != 0,
166 expr_row_major);
167
168 // If this is a column-major row vector or row-major column vector, the inner-stride
169 // is arbitrary, so set it to either the compile-time inner stride or 1.
170 const bool row_vector = (rows == 1);
171 const bool col_vector = (cols == 1);
172 const Index inner_stride =
173 ( (!row_major && row_vector) || (row_major && col_vector) ) ?
174 ( StrideType::InnerStrideAtCompileTime > 0 ? Index(StrideType::InnerStrideAtCompileTime) : 1)
175 : swap_stride ? expr_outer_actual : expr_inner_actual;
176
177 // If this is a column-major column vector or row-major row vector, the outer-stride
178 // is arbitrary, so set it to either the compile-time outer stride or vector size.
179 const Index outer_stride =
180 ( (!row_major && col_vector) || (row_major && row_vector) ) ?
181 ( StrideType::OuterStrideAtCompileTime > 0 ? Index(StrideType::OuterStrideAtCompileTime) : rows * cols * inner_stride)
182 : swap_stride ? expr_inner_actual : expr_outer_actual;
183
184 // Check if given inner/outer strides are compatible with compile-time strides.
185 const bool inner_valid = (StrideType::InnerStrideAtCompileTime == Dynamic)
186 || (resolveInnerStride(Index(StrideType::InnerStrideAtCompileTime)) == inner_stride);
187 if (!inner_valid) {
188 return false;
189 }
190
191 const bool outer_valid = (StrideType::OuterStrideAtCompileTime == Dynamic)
192 || (resolveOuterStride(
193 inner_stride,
194 Index(StrideType::OuterStrideAtCompileTime),
195 rows, cols, PlainObjectType::IsVectorAtCompileTime != 0,
196 row_major)
197 == outer_stride);
198 if (!outer_valid) {
199 return false;
200 }
201
202 ::new (static_cast<Base*>(this)) Base(expr.data(), rows, cols);
203 ::new (&m_stride) StrideBase(
204 (StrideType::OuterStrideAtCompileTime == 0) ? 0 : outer_stride,
205 (StrideType::InnerStrideAtCompileTime == 0) ? 0 : inner_stride );
206 return true;
207 }
208
209 StrideBase m_stride;
210};
211
283template<typename PlainObjectType, int Options, typename StrideType> class Ref
284 : public RefBase<Ref<PlainObjectType, Options, StrideType> >
285{
286 private:
287 typedef internal::traits<Ref> Traits;
288 template<typename Derived>
289 EIGEN_DEVICE_FUNC inline Ref(const PlainObjectBase<Derived>& expr,
290 typename internal::enable_if<bool(Traits::template match<Derived>::MatchAtCompileTime),Derived>::type* = 0);
291 public:
292
293 typedef RefBase<Ref> Base;
294 EIGEN_DENSE_PUBLIC_INTERFACE(Ref)
295
296
297 #ifndef EIGEN_PARSED_BY_DOXYGEN
298 template<typename Derived>
299 EIGEN_DEVICE_FUNC inline Ref(PlainObjectBase<Derived>& expr,
300 typename internal::enable_if<bool(Traits::template match<Derived>::MatchAtCompileTime),Derived>::type* = 0)
301 {
302 EIGEN_STATIC_ASSERT(bool(Traits::template match<Derived>::MatchAtCompileTime), STORAGE_LAYOUT_DOES_NOT_MATCH);
303 // Construction must pass since we will not create temporary storage in the non-const case.
304 const bool success = Base::construct(expr.derived());
305 EIGEN_UNUSED_VARIABLE(success)
306 eigen_assert(success);
307 }
308 template<typename Derived>
309 EIGEN_DEVICE_FUNC inline Ref(const DenseBase<Derived>& expr,
310 typename internal::enable_if<bool(Traits::template match<Derived>::MatchAtCompileTime),Derived>::type* = 0)
311 #else
313 template<typename Derived>
315 #endif
316 {
317 EIGEN_STATIC_ASSERT(bool(internal::is_lvalue<Derived>::value), THIS_EXPRESSION_IS_NOT_A_LVALUE__IT_IS_READ_ONLY);
318 EIGEN_STATIC_ASSERT(bool(Traits::template match<Derived>::MatchAtCompileTime), STORAGE_LAYOUT_DOES_NOT_MATCH);
319 EIGEN_STATIC_ASSERT(!Derived::IsPlainObjectBase,THIS_EXPRESSION_IS_NOT_A_LVALUE__IT_IS_READ_ONLY);
320 // Construction must pass since we will not create temporary storage in the non-const case.
321 const bool success = Base::construct(expr.const_cast_derived());
322 EIGEN_UNUSED_VARIABLE(success)
323 eigen_assert(success);
324 }
325
326 EIGEN_INHERIT_ASSIGNMENT_OPERATORS(Ref)
327
328};
329
330// this is the const ref version
331template<typename TPlainObjectType, int Options, typename StrideType> class Ref<const TPlainObjectType, Options, StrideType>
332 : public RefBase<Ref<const TPlainObjectType, Options, StrideType> >
333{
334 typedef internal::traits<Ref> Traits;
335 public:
336
337 typedef RefBase<Ref> Base;
338 EIGEN_DENSE_PUBLIC_INTERFACE(Ref)
339
340 template<typename Derived>
341 EIGEN_DEVICE_FUNC inline Ref(const DenseBase<Derived>& expr,
342 typename internal::enable_if<bool(Traits::template match<Derived>::ScalarTypeMatch),Derived>::type* = 0)
343 {
344// std::cout << match_helper<Derived>::HasDirectAccess << "," << match_helper<Derived>::OuterStrideMatch << "," << match_helper<Derived>::InnerStrideMatch << "\n";
345// std::cout << int(StrideType::OuterStrideAtCompileTime) << " - " << int(Derived::OuterStrideAtCompileTime) << "\n";
346// std::cout << int(StrideType::InnerStrideAtCompileTime) << " - " << int(Derived::InnerStrideAtCompileTime) << "\n";
347 construct(expr.derived(), typename Traits::template match<Derived>::type());
348 }
349
350 EIGEN_DEVICE_FUNC inline Ref(const Ref& other) : Base(other) {
351 // copy constructor shall not copy the m_object, to avoid unnecessary malloc and copy
352 }
353
354 template<typename OtherRef>
355 EIGEN_DEVICE_FUNC inline Ref(const RefBase<OtherRef>& other) {
356 construct(other.derived(), typename Traits::template match<OtherRef>::type());
357 }
358
359 protected:
360
361 template<typename Expression>
362 EIGEN_DEVICE_FUNC void construct(const Expression& expr,internal::true_type)
363 {
364 // Check if we can use the underlying expr's storage directly, otherwise call the copy version.
365 if (!Base::construct(expr)) {
366 construct(expr, internal::false_type());
367 }
368 }
369
370 template<typename Expression>
371 EIGEN_DEVICE_FUNC void construct(const Expression& expr, internal::false_type)
372 {
373 internal::call_assignment_no_alias(m_object,expr,internal::assign_op<Scalar,Scalar>());
374 Base::construct(m_object);
375 }
376
377 protected:
378 TPlainObjectType m_object;
379};
380
381} // end namespace Eigen
382
383#endif // EIGEN_REF_H
Base class for all dense matrices, vectors, and arrays.
Definition: DenseBase.h:42
Dense storage base class for matrices and arrays.
Definition: PlainObjectBase.h:102
A matrix or vector expression mapping an existing expression.
Definition: Ref.h:285
Ref(DenseBase< Derived > &expr)
Definition: Ref.h:314
@ Unaligned
Definition: Constants.h:235
const unsigned int RowMajorBit
Definition: Constants.h:68
Namespace containing all symbols from the Eigen library.
Definition: B01_Experimental.dox:1
EIGEN_DEFAULT_DENSE_INDEX_TYPE Index
The Index type as used for the API.
Definition: Meta.h:59
const int Dynamic
Definition: Constants.h:24