devtools/eigen
1
0
Fork 0
mirror of https://gitlab.com/libeigen/eigen.git synced 2026-04-10 11:34:33 +08:00
Code Issues Packages Projects Releases Wiki Activity

Make fixed-size Matrix and Array trivially copyable after C++20

Browse Source 
Making them trivially copyable allows using std::memcpy() without undefined
behaviors.

Only Matrix and Array with trivially copyable DenseStorage are marked as
trivially copyable with an additional type trait.

As described in http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p0848r3.html
it requires extremely verbose SFINAE to make the special member functions of
fixed-size Matrix and Array trivial, unless C++20 concepts are available to
simplify the selection of trivial special member functions given template
parameters. Therefore only make this feature available to compilers that support
C++20 P0848R3.

Fix #1855.
This commit is contained in:
Lingzhu Xiang
2022-01-07 19:04:35 +00:00
committed by David Tellenbach
parent c4b1dd2f6b
commit 47eac21072
11 changed files with 127 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files

23
Eigen/src/Core/Array.h
View File

@@ -21,6 +21,10 @@ struct traits<Array<Scalar_, Rows_, Cols_, Options_, MaxRows_, MaxCols_> > : tra
typedef ArrayXpr XprKind;
typedef ArrayBase<Array<Scalar_, Rows_, Cols_, Options_, MaxRows_, MaxCols_> > XprBase;
};
template<typename Scalar_, int Rows_, int Cols_, int Options_, int MaxRows_, int MaxCols_>
struct has_trivially_copyable_storage<Array<Scalar_, Rows_, Cols_, Options_, MaxRows_, MaxCols_> >
: has_trivially_copyable_storage<Matrix<Scalar_, Rows_, Cols_, Options_, MaxRows_, MaxCols_> > {};
}
/** \class Array
@@ -120,6 +124,12 @@ class Array
return Base::_set(other);
}
#if EIGEN_COMP_HAS_P0848R3
EIGEN_DEVICE_FUNC
EIGEN_STRONG_INLINE Array& operator=(
const Array& other) requires internal::has_trivially_copyable_storage<Array>::value = default;
#endif
/** Default constructor.
*
* For fixed-size matrices, does nothing.
@@ -159,6 +169,13 @@ class Array
return *this;
}
#if EIGEN_COMP_HAS_P0848R3
EIGEN_DEVICE_FUNC Array(Array&& other) EIGEN_NOEXCEPT
requires internal::has_trivially_copyable_storage<Array>::value = default;
EIGEN_DEVICE_FUNC Array& operator=(Array&& other) EIGEN_NOEXCEPT
requires internal::has_trivially_copyable_storage<Array>::value = default;
#endif
/** \copydoc PlainObjectBase(const Scalar& a0, const Scalar& a1, const Scalar& a2, const Scalar& a3, const ArgTypes&... args)
*
* Example: \include Array_variadic_ctor_cxx11.cpp
@@ -266,6 +283,12 @@ class Array
: Base(other)
{ }
#if EIGEN_COMP_HAS_P0848R3
EIGEN_DEVICE_FUNC
EIGEN_STRONG_INLINE Array(const Array& other) requires internal::has_trivially_copyable_storage<Array>::value =
default;
#endif
private:
struct PrivateType {};
public: