eigen/Eigen/src/Core/util/BlasUtil.h
Gael Guennebaud 6a5fe86098 Complete rewrite of column-major-matrix * vector product to deliver higher performance of modern CPU.
The previous code has been optimized for Intel core2 for which unaligned loads/stores were prohibitively expensive.
This new version exhibits much higher instruction independence (better pipelining) and explicitly leverage FMA.
According to my benchmark, on Haswell this new kernel is always faster than the previous one, and sometimes even twice as fast.
Even higher performance could be achieved with a better blocking size heuristic and, perhaps, with explicit prefetching.
We should also check triangular product/solve to optimally exploit this new kernel (working on vertical panel of 4 columns is probably not optimal anymore).
2016-12-03 21:14:14 +01:00

405 lines
16 KiB
C++
Executable File

// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2009-2010 Gael Guennebaud <gael.guennebaud@inria.fr>
//
// This Source Code Form is subject to the terms of the Mozilla
// Public License v. 2.0. If a copy of the MPL was not distributed
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
#ifndef EIGEN_BLASUTIL_H
#define EIGEN_BLASUTIL_H
// This file contains many lightweight helper classes used to
// implement and control fast level 2 and level 3 BLAS-like routines.
namespace Eigen {
namespace internal {
// forward declarations
template<typename LhsScalar, typename RhsScalar, typename Index, typename DataMapper, int mr, int nr, bool ConjugateLhs=false, bool ConjugateRhs=false>
struct gebp_kernel;
template<typename Scalar, typename Index, typename DataMapper, int nr, int StorageOrder, bool Conjugate = false, bool PanelMode=false>
struct gemm_pack_rhs;
template<typename Scalar, typename Index, typename DataMapper, int Pack1, int Pack2, int StorageOrder, bool Conjugate = false, bool PanelMode = false>
struct gemm_pack_lhs;
template<
typename Index,
typename LhsScalar, int LhsStorageOrder, bool ConjugateLhs,
typename RhsScalar, int RhsStorageOrder, bool ConjugateRhs,
int ResStorageOrder>
struct general_matrix_matrix_product;
template<typename Index,
typename LhsScalar, typename LhsMapper, int LhsStorageOrder, bool ConjugateLhs,
typename RhsScalar, typename RhsMapper, bool ConjugateRhs, int Version=Specialized>
struct general_matrix_vector_product;
template<bool Conjugate> struct conj_if;
template<> struct conj_if<true> {
template<typename T>
inline T operator()(const T& x) const { return numext::conj(x); }
template<typename T>
inline T pconj(const T& x) const { return internal::pconj(x); }
};
template<> struct conj_if<false> {
template<typename T>
inline const T& operator()(const T& x) const { return x; }
template<typename T>
inline const T& pconj(const T& x) const { return x; }
};
// Generic implementation for custom complex types.
template<typename LhsScalar, typename RhsScalar, bool ConjLhs, bool ConjRhs>
struct conj_helper
{
typedef typename ScalarBinaryOpTraits<LhsScalar,RhsScalar>::ReturnType Scalar;
EIGEN_STRONG_INLINE Scalar pmadd(const LhsScalar& x, const RhsScalar& y, const Scalar& c) const
{ return padd(c, pmul(x,y)); }
EIGEN_STRONG_INLINE Scalar pmul(const LhsScalar& x, const RhsScalar& y) const
{ return conj_if<ConjLhs>()(x) * conj_if<ConjRhs>()(y); }
};
template<typename Scalar> struct conj_helper<Scalar,Scalar,false,false>
{
EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE Scalar pmadd(const Scalar& x, const Scalar& y, const Scalar& c) const { return internal::pmadd(x,y,c); }
EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE Scalar pmul(const Scalar& x, const Scalar& y) const { return internal::pmul(x,y); }
};
template<typename RealScalar> struct conj_helper<std::complex<RealScalar>, std::complex<RealScalar>, false,true>
{
typedef std::complex<RealScalar> Scalar;
EIGEN_STRONG_INLINE Scalar pmadd(const Scalar& x, const Scalar& y, const Scalar& c) const
{ return c + pmul(x,y); }
EIGEN_STRONG_INLINE Scalar pmul(const Scalar& x, const Scalar& y) const
{ return Scalar(numext::real(x)*numext::real(y) + numext::imag(x)*numext::imag(y), numext::imag(x)*numext::real(y) - numext::real(x)*numext::imag(y)); }
};
template<typename RealScalar> struct conj_helper<std::complex<RealScalar>, std::complex<RealScalar>, true,false>
{
typedef std::complex<RealScalar> Scalar;
EIGEN_STRONG_INLINE Scalar pmadd(const Scalar& x, const Scalar& y, const Scalar& c) const
{ return c + pmul(x,y); }
EIGEN_STRONG_INLINE Scalar pmul(const Scalar& x, const Scalar& y) const
{ return Scalar(numext::real(x)*numext::real(y) + numext::imag(x)*numext::imag(y), numext::real(x)*numext::imag(y) - numext::imag(x)*numext::real(y)); }
};
template<typename RealScalar> struct conj_helper<std::complex<RealScalar>, std::complex<RealScalar>, true,true>
{
typedef std::complex<RealScalar> Scalar;
EIGEN_STRONG_INLINE Scalar pmadd(const Scalar& x, const Scalar& y, const Scalar& c) const
{ return c + pmul(x,y); }
EIGEN_STRONG_INLINE Scalar pmul(const Scalar& x, const Scalar& y) const
{ return Scalar(numext::real(x)*numext::real(y) - numext::imag(x)*numext::imag(y), - numext::real(x)*numext::imag(y) - numext::imag(x)*numext::real(y)); }
};
template<typename RealScalar,bool Conj> struct conj_helper<std::complex<RealScalar>, RealScalar, Conj,false>
{
typedef std::complex<RealScalar> Scalar;
EIGEN_STRONG_INLINE Scalar pmadd(const Scalar& x, const RealScalar& y, const Scalar& c) const
{ return padd(c, pmul(x,y)); }
EIGEN_STRONG_INLINE Scalar pmul(const Scalar& x, const RealScalar& y) const
{ return conj_if<Conj>()(x)*y; }
};
template<typename RealScalar,bool Conj> struct conj_helper<RealScalar, std::complex<RealScalar>, false,Conj>
{
typedef std::complex<RealScalar> Scalar;
EIGEN_STRONG_INLINE Scalar pmadd(const RealScalar& x, const Scalar& y, const Scalar& c) const
{ return padd(c, pmul(x,y)); }
EIGEN_STRONG_INLINE Scalar pmul(const RealScalar& x, const Scalar& y) const
{ return x*conj_if<Conj>()(y); }
};
template<typename From,typename To> struct get_factor {
EIGEN_DEVICE_FUNC static EIGEN_STRONG_INLINE To run(const From& x) { return To(x); }
};
template<typename Scalar> struct get_factor<Scalar,typename NumTraits<Scalar>::Real> {
EIGEN_DEVICE_FUNC
static EIGEN_STRONG_INLINE typename NumTraits<Scalar>::Real run(const Scalar& x) { return numext::real(x); }
};
template<typename Scalar, typename Index>
class BlasVectorMapper {
public:
EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE BlasVectorMapper(Scalar *data) : m_data(data) {}
EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE Scalar operator()(Index i) const {
return m_data[i];
}
template <typename Packet, int AlignmentType>
EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE Packet load(Index i) const {
return ploadt<Packet, AlignmentType>(m_data + i);
}
template <typename Packet>
EIGEN_DEVICE_FUNC bool aligned(Index i) const {
return (UIntPtr(m_data+i)%sizeof(Packet))==0;
}
protected:
Scalar* m_data;
};
template<typename Scalar, typename Index, int AlignmentType>
class BlasLinearMapper {
public:
typedef typename packet_traits<Scalar>::type Packet;
typedef typename packet_traits<Scalar>::half HalfPacket;
EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE BlasLinearMapper(Scalar *data) : m_data(data) {}
EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE void prefetch(int i) const {
internal::prefetch(&operator()(i));
}
EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE Scalar& operator()(Index i) const {
return m_data[i];
}
EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE Packet loadPacket(Index i) const {
return ploadt<Packet, AlignmentType>(m_data + i);
}
EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE HalfPacket loadHalfPacket(Index i) const {
return ploadt<HalfPacket, AlignmentType>(m_data + i);
}
EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE void storePacket(Index i, const Packet &p) const {
pstoret<Scalar, Packet, AlignmentType>(m_data + i, p);
}
protected:
Scalar *m_data;
};
// Lightweight helper class to access matrix coefficients.
template<typename Scalar, typename Index, int StorageOrder, int AlignmentType = Unaligned>
class blas_data_mapper {
public:
typedef typename packet_traits<Scalar>::type Packet;
typedef typename packet_traits<Scalar>::half HalfPacket;
typedef BlasLinearMapper<Scalar, Index, AlignmentType> LinearMapper;
typedef BlasVectorMapper<Scalar, Index> VectorMapper;
EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE blas_data_mapper(Scalar* data, Index stride) : m_data(data), m_stride(stride) {}
EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE blas_data_mapper<Scalar, Index, StorageOrder, AlignmentType>
getSubMapper(Index i, Index j) const {
return blas_data_mapper<Scalar, Index, StorageOrder, AlignmentType>(&operator()(i, j), m_stride);
}
EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE LinearMapper getLinearMapper(Index i, Index j) const {
return LinearMapper(&operator()(i, j));
}
EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE VectorMapper getVectorMapper(Index i, Index j) const {
return VectorMapper(&operator()(i, j));
}
EIGEN_DEVICE_FUNC
EIGEN_ALWAYS_INLINE Scalar& operator()(Index i, Index j) const {
return m_data[StorageOrder==RowMajor ? j + i*m_stride : i + j*m_stride];
}
EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE Packet loadPacket(Index i, Index j) const {
return ploadt<Packet, AlignmentType>(&operator()(i, j));
}
template <typename PacketT, int AlignmentT>
EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE PacketT load(Index i, Index j) const {
//return ploadt<PacketT, AlignmentT>(&operator()(i, j));
return ploadu<PacketT>(m_data+j*m_stride+i);
}
EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE HalfPacket loadHalfPacket(Index i, Index j) const {
return ploadt<HalfPacket, AlignmentType>(&operator()(i, j));
}
template<typename SubPacket>
EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE void scatterPacket(Index i, Index j, const SubPacket &p) const {
pscatter<Scalar, SubPacket>(&operator()(i, j), p, m_stride);
}
template<typename SubPacket>
EIGEN_DEVICE_FUNC EIGEN_ALWAYS_INLINE SubPacket gatherPacket(Index i, Index j) const {
return pgather<Scalar, SubPacket>(&operator()(i, j), m_stride);
}
EIGEN_DEVICE_FUNC const Index stride() const { return m_stride; }
EIGEN_DEVICE_FUNC const Scalar* data() const { return m_data; }
EIGEN_DEVICE_FUNC Index firstAligned(Index size) const {
if (UIntPtr(m_data)%sizeof(Scalar)) {
return -1;
}
return internal::first_default_aligned(m_data, size);
}
protected:
Scalar* EIGEN_RESTRICT m_data;
const Index m_stride;
};
// lightweight helper class to access matrix coefficients (const version)
template<typename Scalar, typename Index, int StorageOrder>
class const_blas_data_mapper : public blas_data_mapper<const Scalar, Index, StorageOrder> {
public:
EIGEN_ALWAYS_INLINE const_blas_data_mapper(const Scalar *data, Index stride) : blas_data_mapper<const Scalar, Index, StorageOrder>(data, stride) {}
EIGEN_ALWAYS_INLINE const_blas_data_mapper<Scalar, Index, StorageOrder> getSubMapper(Index i, Index j) const {
return const_blas_data_mapper<Scalar, Index, StorageOrder>(&(this->operator()(i, j)), this->m_stride);
}
};
/* Helper class to analyze the factors of a Product expression.
* In particular it allows to pop out operator-, scalar multiples,
* and conjugate */
template<typename XprType> struct blas_traits
{
typedef typename traits<XprType>::Scalar Scalar;
typedef const XprType& ExtractType;
typedef XprType _ExtractType;
enum {
IsComplex = NumTraits<Scalar>::IsComplex,
IsTransposed = false,
NeedToConjugate = false,
HasUsableDirectAccess = ( (int(XprType::Flags)&DirectAccessBit)
&& ( bool(XprType::IsVectorAtCompileTime)
|| int(inner_stride_at_compile_time<XprType>::ret) == 1)
) ? 1 : 0
};
typedef typename conditional<bool(HasUsableDirectAccess),
ExtractType,
typename _ExtractType::PlainObject
>::type DirectLinearAccessType;
static inline ExtractType extract(const XprType& x) { return x; }
static inline const Scalar extractScalarFactor(const XprType&) { return Scalar(1); }
};
// pop conjugate
template<typename Scalar, typename NestedXpr>
struct blas_traits<CwiseUnaryOp<scalar_conjugate_op<Scalar>, NestedXpr> >
: blas_traits<NestedXpr>
{
typedef blas_traits<NestedXpr> Base;
typedef CwiseUnaryOp<scalar_conjugate_op<Scalar>, NestedXpr> XprType;
typedef typename Base::ExtractType ExtractType;
enum {
IsComplex = NumTraits<Scalar>::IsComplex,
NeedToConjugate = Base::NeedToConjugate ? 0 : IsComplex
};
static inline ExtractType extract(const XprType& x) { return Base::extract(x.nestedExpression()); }
static inline Scalar extractScalarFactor(const XprType& x) { return conj(Base::extractScalarFactor(x.nestedExpression())); }
};
// pop scalar multiple
template<typename Scalar, typename NestedXpr, typename Plain>
struct blas_traits<CwiseBinaryOp<scalar_product_op<Scalar>, const CwiseNullaryOp<scalar_constant_op<Scalar>,Plain>, NestedXpr> >
: blas_traits<NestedXpr>
{
typedef blas_traits<NestedXpr> Base;
typedef CwiseBinaryOp<scalar_product_op<Scalar>, const CwiseNullaryOp<scalar_constant_op<Scalar>,Plain>, NestedXpr> XprType;
typedef typename Base::ExtractType ExtractType;
static inline ExtractType extract(const XprType& x) { return Base::extract(x.rhs()); }
static inline Scalar extractScalarFactor(const XprType& x)
{ return x.lhs().functor().m_other * Base::extractScalarFactor(x.rhs()); }
};
template<typename Scalar, typename NestedXpr, typename Plain>
struct blas_traits<CwiseBinaryOp<scalar_product_op<Scalar>, NestedXpr, const CwiseNullaryOp<scalar_constant_op<Scalar>,Plain> > >
: blas_traits<NestedXpr>
{
typedef blas_traits<NestedXpr> Base;
typedef CwiseBinaryOp<scalar_product_op<Scalar>, NestedXpr, const CwiseNullaryOp<scalar_constant_op<Scalar>,Plain> > XprType;
typedef typename Base::ExtractType ExtractType;
static inline ExtractType extract(const XprType& x) { return Base::extract(x.lhs()); }
static inline Scalar extractScalarFactor(const XprType& x)
{ return Base::extractScalarFactor(x.lhs()) * x.rhs().functor().m_other; }
};
template<typename Scalar, typename Plain1, typename Plain2>
struct blas_traits<CwiseBinaryOp<scalar_product_op<Scalar>, const CwiseNullaryOp<scalar_constant_op<Scalar>,Plain1>,
const CwiseNullaryOp<scalar_constant_op<Scalar>,Plain2> > >
: blas_traits<CwiseNullaryOp<scalar_constant_op<Scalar>,Plain1> >
{};
// pop opposite
template<typename Scalar, typename NestedXpr>
struct blas_traits<CwiseUnaryOp<scalar_opposite_op<Scalar>, NestedXpr> >
: blas_traits<NestedXpr>
{
typedef blas_traits<NestedXpr> Base;
typedef CwiseUnaryOp<scalar_opposite_op<Scalar>, NestedXpr> XprType;
typedef typename Base::ExtractType ExtractType;
static inline ExtractType extract(const XprType& x) { return Base::extract(x.nestedExpression()); }
static inline Scalar extractScalarFactor(const XprType& x)
{ return - Base::extractScalarFactor(x.nestedExpression()); }
};
// pop/push transpose
template<typename NestedXpr>
struct blas_traits<Transpose<NestedXpr> >
: blas_traits<NestedXpr>
{
typedef typename NestedXpr::Scalar Scalar;
typedef blas_traits<NestedXpr> Base;
typedef Transpose<NestedXpr> XprType;
typedef Transpose<const typename Base::_ExtractType> ExtractType; // const to get rid of a compile error; anyway blas traits are only used on the RHS
typedef Transpose<const typename Base::_ExtractType> _ExtractType;
typedef typename conditional<bool(Base::HasUsableDirectAccess),
ExtractType,
typename ExtractType::PlainObject
>::type DirectLinearAccessType;
enum {
IsTransposed = Base::IsTransposed ? 0 : 1
};
static inline ExtractType extract(const XprType& x) { return ExtractType(Base::extract(x.nestedExpression())); }
static inline Scalar extractScalarFactor(const XprType& x) { return Base::extractScalarFactor(x.nestedExpression()); }
};
template<typename T>
struct blas_traits<const T>
: blas_traits<T>
{};
template<typename T, bool HasUsableDirectAccess=blas_traits<T>::HasUsableDirectAccess>
struct extract_data_selector {
static const typename T::Scalar* run(const T& m)
{
return blas_traits<T>::extract(m).data();
}
};
template<typename T>
struct extract_data_selector<T,false> {
static typename T::Scalar* run(const T&) { return 0; }
};
template<typename T> const typename T::Scalar* extract_data(const T& m)
{
return extract_data_selector<T>::run(m);
}
} // end namespace internal
} // end namespace Eigen
#endif // EIGEN_BLASUTIL_H