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https://gitlab.com/libeigen/eigen.git
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Add a *very efficient* evaluation path for both col-major matrix * vector
and vector * row-major products. Currently, it is enabled only is the matrix has DirectAccessBit flag and the product is "large enough". Added the respective unit tests in test/product/cpp.
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@ -59,10 +59,7 @@ namespace Eigen {
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#include "src/Core/CommaInitializer.h"
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#include "src/Core/Extract.h"
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#include "src/Core/Part.h"
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#ifndef EIGEN_EXTERN_INSTANTIATIONS
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#include "src/Core/CacheFriendlyProduct.h"
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#endif
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} // namespace Eigen
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@ -249,7 +249,6 @@ struct ei_assign_impl<Derived1, Derived2, InnerVectorization, NoUnrolling>
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{
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static void run(Derived1 &dst, const Derived2 &src)
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{
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const bool rowMajor = int(Derived1::Flags)&RowMajorBit;
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const int innerSize = dst.innerSize();
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const int outerSize = dst.outerSize();
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const int packetSize = ei_packet_traits<typename Derived1::Scalar>::size;
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@ -155,7 +155,6 @@ template<typename MatrixType, int BlockRows, int BlockCols> class Block
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return m_matrix.const_cast_derived()
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.coeffRef(m_startRow.value() + (RowsAtCompileTime == 1 ? 0 : index),
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m_startCol.value() + (RowsAtCompileTime == 1 ? index : 0));
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}
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inline const Scalar coeff(int index) const
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@ -25,6 +25,8 @@
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#ifndef EIGEN_CACHE_FRIENDLY_PRODUCT_H
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#define EIGEN_CACHE_FRIENDLY_PRODUCT_H
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#ifndef EIGEN_EXTERN_INSTANTIATIONS
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template<typename Scalar>
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static void ei_cache_friendly_product(
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int _rows, int _cols, int depth,
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@ -77,8 +79,6 @@ static void ei_cache_friendly_product(
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MaxL2BlockSize = EIGEN_TUNE_FOR_L2_CACHE_SIZE / sizeof(Scalar)
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};
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//const bool rhsIsAligned = (PacketSize==1) || (((rhsStride%PacketSize) == 0) && (size_t(rhs)%16==0));
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const bool resIsAligned = (PacketSize==1) || (((resStride%PacketSize) == 0) && (size_t(res)%16==0));
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const int remainingSize = depth % PacketSize;
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@ -357,4 +357,165 @@ static void ei_cache_friendly_product(
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free(block);
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}
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#endif // EIGEN_EXTERN_INSTANTIATIONS
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/* Optimized col-major matrix * vector product:
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* This algorithm processes 4 columns at onces that allows to both reduce
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* the number of load/stores of the result by a factor 4 and to reduce
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* the instruction dependency. Moreover, we know that all bands have the
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* same alignment pattern.
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* TODO: since rhs gets evaluated only once, no need to evaluate it
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*/
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template<typename Scalar, typename RhsType>
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EIGEN_DONT_INLINE static void ei_cache_friendly_product(
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int size,
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const Scalar* lhs, int lhsStride,
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const RhsType& rhs,
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Scalar* res)
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{
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#ifdef _EIGEN_ACCUMULATE_PACKETS
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#error _EIGEN_ACCUMULATE_PACKETS has already been defined
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#endif
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#define _EIGEN_ACCUMULATE_PACKETS(A0,A13,A2,OFFSET) \
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ei_pstore(&res[j OFFSET], \
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ei_padd(ei_pload(&res[j OFFSET]), \
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ei_padd( \
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ei_padd(ei_pmul(ptmp0,ei_pload ## A0(&lhs[j OFFSET +iN0])),ei_pmul(ptmp1,ei_pload ## A13(&lhs[j OFFSET +iN1]))), \
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ei_padd(ei_pmul(ptmp2,ei_pload ## A2(&lhs[j OFFSET +iN2])),ei_pmul(ptmp3,ei_pload ## A13(&lhs[j OFFSET +iN3]))) )))
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asm("#begin matrix_vector_product");
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typedef typename ei_packet_traits<Scalar>::type Packet;
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const int PacketSize = sizeof(Packet)/sizeof(Scalar);
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enum { AllAligned, EvenAligned, FirstAligned, NoneAligned };
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const int columnsAtOnce = 4;
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const int peels = 2;
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const int PacketAlignedMask = PacketSize-1;
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const int PeelAlignedMask = PacketSize*peels-1;
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const bool Vectorized = sizeof(Packet) != sizeof(Scalar);
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// How many coeffs of the result do we have to skip to be aligned.
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// Here we assume data are at least aligned on the base scalar type that is mandatory anyway.
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const int alignedStart = Vectorized
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? std::min<int>( (PacketSize - ((size_t(res)/sizeof(Scalar)) & PacketAlignedMask)) & PacketAlignedMask, size)
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: 0;
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const int alignedSize = alignedStart + ((size-alignedStart) & ~PacketAlignedMask);
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const int peeledSize = peels>1 ? alignedStart + ((alignedSize-alignedStart) & ~PeelAlignedMask) : 0;
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const int alignmentStep = lhsStride % PacketSize;
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int alignmentPattern = alignmentStep==0 ? AllAligned
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: alignmentStep==2 ? EvenAligned
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: FirstAligned;
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// find how many column do we have to skip to be aligned with the result (if possible)
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int skipColumns=0;
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for (; skipColumns<PacketSize; ++skipColumns)
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{
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if (alignedStart == alignmentStep*skipColumns)
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break;
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}
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if (skipColumns==PacketSize)
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alignmentPattern = NoneAligned;
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skipColumns = std::min(skipColumns,rhs.size());
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if (alignmentPattern!=NoneAligned)
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for (int i=0; i<skipColumns; i++)
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{
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Scalar tmp0 = rhs[i];
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Packet ptmp0 = ei_pset1(tmp0);
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int iN0 = i*lhsStride;
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// process first unaligned result's coeffs
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for (int j=0; j<alignedStart; j++)
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res[j] += tmp0 * lhs[j+iN0];
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// process aligned result's coeffs (we know the lhs columns are not aligned)
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for (int j = alignedStart;j<alignedSize;j+=PacketSize)
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ei_pstore(&res[j], ei_padd(ei_pmul(ptmp0,ei_ploadu(&lhs[j+iN0])),ei_pload(&res[j])));
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// process remaining result's coeffs
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for (int j=alignedSize; j<size; j++)
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res[j] += tmp0 * lhs[j+iN0];
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}
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int columnBound = (rhs.size()/columnsAtOnce)*columnsAtOnce;
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for (int i=0; i<columnBound; i+=columnsAtOnce)
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{
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Scalar tmp0 = rhs[i];
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Packet ptmp0 = ei_pset1(tmp0);
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Scalar tmp1 = rhs[i+1];
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Packet ptmp1 = ei_pset1(tmp1);
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Scalar tmp2 = rhs[i+2];
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Packet ptmp2 = ei_pset1(tmp2);
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Scalar tmp3 = rhs[i+3];
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Packet ptmp3 = ei_pset1(tmp3);
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int iN0 = i*lhsStride;
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int iN1 = (i+1)*lhsStride;
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int iN2 = (i+2)*lhsStride;
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int iN3 = (i+3)*lhsStride;
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// process initial unaligned coeffs
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for (int j=0; j<alignedStart; j++)
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res[j] += tmp0 * lhs[j+iN0] + tmp1 * lhs[j+iN1] + tmp2 * lhs[j+iN2] + tmp3 * lhs[j+iN3];
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if (alignedSize>0)
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{
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switch(alignmentPattern)
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{
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case AllAligned:
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for (int j = alignedStart; j<alignedSize; j+=PacketSize)
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_EIGEN_ACCUMULATE_PACKETS(,,,);
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break;
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case EvenAligned:
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for (int j = alignedStart; j<alignedSize; j+=PacketSize)
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_EIGEN_ACCUMULATE_PACKETS(,u,,);
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break;
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case FirstAligned:
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if (peels>1)
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for (int j = alignedStart; j<peeledSize; j+=peels*PacketSize)
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{
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_EIGEN_ACCUMULATE_PACKETS(,u,u,);
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_EIGEN_ACCUMULATE_PACKETS(,u,u,+PacketSize);
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if (peels>2) _EIGEN_ACCUMULATE_PACKETS(,u,u,+2*PacketSize);
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if (peels>3) _EIGEN_ACCUMULATE_PACKETS(,u,u,+3*PacketSize);
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if (peels>4) _EIGEN_ACCUMULATE_PACKETS(,u,u,+4*PacketSize);
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if (peels>5) _EIGEN_ACCUMULATE_PACKETS(,u,u,+5*PacketSize);
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if (peels>6) _EIGEN_ACCUMULATE_PACKETS(,u,u,+6*PacketSize);
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if (peels>7) _EIGEN_ACCUMULATE_PACKETS(,u,u,+7*PacketSize);
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}
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for (int j = peeledSize; j<alignedSize; j+=PacketSize)
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_EIGEN_ACCUMULATE_PACKETS(,u,u,);
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break;
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default:
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for (int j = peeledSize; j<alignedSize; j+=PacketSize)
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_EIGEN_ACCUMULATE_PACKETS(u,u,u,);
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break;
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}
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}
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// process remaining coeffs
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for (int j=alignedSize; j<size; j++)
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res[j] += tmp0 * lhs[j+iN0] + tmp1 * lhs[j+iN1] + tmp2 * lhs[j+iN2] + tmp3 * lhs[j+iN3];
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}
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for (int i=columnBound; i<rhs.size(); i++)
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{
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Scalar tmp0 = rhs[i];
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Packet ptmp0 = ei_pset1(tmp0);
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int iN0 = i*lhsStride;
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if (alignedSize>0)
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{
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bool aligned0 = (iN0 % PacketSize) == 0;
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if (aligned0)
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for (int j = 0;j<alignedSize;j+=PacketSize)
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ei_pstore(&res[j], ei_padd(ei_pmul(ptmp0,ei_pload(&lhs[j+iN0])),ei_pload(&res[j])));
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else
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for (int j = 0;j<alignedSize;j+=PacketSize)
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ei_pstore(&res[j], ei_padd(ei_pmul(ptmp0,ei_ploadu(&lhs[j+iN0])),ei_pload(&res[j])));
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}
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// process remaining scalars
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for (int j=alignedSize; j<size; j++)
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res[j] += tmp0 * lhs[j+iN0];
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}
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asm("#end matrix_vector_product");
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#undef _EIGEN_ACCUMULATE_PACKETS
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}
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#endif // EIGEN_CACHE_FRIENDLY_PRODUCT_H
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@ -250,8 +250,8 @@ template<typename LhsNested, typename RhsNested, int ProductMode> class Product
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return res;
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}
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const _LhsNested& lhs() const { return m_lhs; }
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const _RhsNested& rhs() const { return m_rhs; }
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inline const _LhsNested& lhs() const { return m_lhs; }
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inline const _RhsNested& rhs() const { return m_rhs; }
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protected:
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const LhsNested m_lhs;
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@ -480,11 +480,22 @@ struct ei_product_packet_impl<ColMajor, Dynamic, Lhs, Rhs, PacketScalar, LoadMod
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* Cache friendly product callers and specific nested evaluation strategies
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***************************************************************************/
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template<typename Scalar, typename RhsType>
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static void ei_cache_friendly_product(
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int size, const Scalar* lhs, int lhsStride, const RhsType& rhs, Scalar* res);
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enum {
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HasDirectAccess,
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NoDirectAccess
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};
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template<typename ProductType,
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int LhsRows = ei_traits<ProductType>::RowsAtCompileTime,
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int LhsOrder = int(ei_traits<ProductType>::LhsFlags)&RowMajorBit ? RowMajor : ColMajor,
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int LhsHasDirectAccess = int(ei_traits<ProductType>::LhsFlags)&DirectAccessBit? HasDirectAccess : NoDirectAccess,
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int RhsCols = ei_traits<ProductType>::ColsAtCompileTime,
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int RhsOrder = int(ei_traits<ProductType>::RhsFlags)&RowMajorBit ? RowMajor : ColMajor>
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int RhsOrder = int(ei_traits<ProductType>::RhsFlags)&RowMajorBit ? RowMajor : ColMajor,
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int RhsHasDirectAccess = int(ei_traits<ProductType>::RhsFlags)&DirectAccessBit? HasDirectAccess : NoDirectAccess>
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struct ei_cache_friendly_product_selector
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{
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template<typename DestDerived>
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@ -495,21 +506,57 @@ struct ei_cache_friendly_product_selector
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};
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// optimized colmajor * vector path
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template<typename ProductType, int LhsRows, int RhsOrder>
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struct ei_cache_friendly_product_selector<ProductType,LhsRows,ColMajor,1,RhsOrder>
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template<typename ProductType, int LhsRows, int RhsOrder, int RhsAccess>
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struct ei_cache_friendly_product_selector<ProductType,LhsRows,NoDirectAccess,ColMajor,1,RhsOrder,RhsAccess>
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{
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typedef typename ei_traits<ProductType>::_LhsNested Lhs;
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template<typename DestDerived>
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inline static void run(DestDerived& res, const ProductType& product)
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{
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const int rows = product.rhs().rows();
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for (int j=0; j<rows; ++j)
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res += product.rhs().coeff(j) * product.lhs().col(j);
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ei_scalar_sum_op<typename ProductType::Scalar> _sum;
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const int size = product.rhs().rows();
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for (int k=0; k<size; ++k)
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if (Lhs::Flags&DirectAccessBit)
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// TODO to properly hanlde this workaround let's specialize Block for type having the DirectAccessBit
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res += product.rhs().coeff(k) * Map<DestDerived>(&product.lhs().const_cast_derived().coeffRef(0,k),product.lhs().rows());
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else
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res += product.rhs().coeff(k) * product.lhs().col(k);
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}
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};
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// optimized cache friendly colmajor * vector path for matrix with direct access flag
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// NOTE this path coul also be enabled for expressions if we add runtime align queries
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template<typename ProductType, int LhsRows, int RhsOrder, int RhsAccess>
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struct ei_cache_friendly_product_selector<ProductType,LhsRows,HasDirectAccess,ColMajor,1,RhsOrder,RhsAccess>
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{
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typedef typename ProductType::Scalar Scalar;
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template<typename DestDerived>
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inline static void run(DestDerived& res, const ProductType& product)
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{
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enum {
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EvalToRes = (ei_packet_traits<Scalar>::size==1)
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||(DestDerived::Flags&ActualPacketAccessBit) && (!(DestDerived::Flags & RowMajorBit)) };
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Scalar* __restrict__ _res;
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if (EvalToRes)
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_res = &res.coeffRef(0);
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else
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{
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_res = (Scalar*)alloca(sizeof(Scalar)*res.size());
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Map<Matrix<Scalar,DestDerived::RowsAtCompileTime,1> >(_res, res.size()) = res;
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}
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ei_cache_friendly_product(res.size(),
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&product.lhs().const_cast_derived().coeffRef(0,0), product.lhs().stride(),
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product.rhs(), _res);
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if (!EvalToRes)
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res = Map<Matrix<Scalar,DestDerived::RowsAtCompileTime,1> >(_res, res.size());
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}
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};
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// optimized vector * rowmajor path
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template<typename ProductType, int LhsOrder, int RhsCols>
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struct ei_cache_friendly_product_selector<ProductType,1,LhsOrder,RhsCols,RowMajor>
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template<typename ProductType, int LhsOrder, int LhsAccess, int RhsCols>
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struct ei_cache_friendly_product_selector<ProductType,1,LhsOrder,LhsAccess,RhsCols,RowMajor,NoDirectAccess>
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{
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template<typename DestDerived>
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inline static void run(DestDerived& res, const ProductType& product)
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@ -520,6 +567,36 @@ struct ei_cache_friendly_product_selector<ProductType,1,LhsOrder,RhsCols,RowMajo
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}
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};
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// optimized cache friendly vector * rowmajor path for matrix with direct access flag
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// NOTE this path coul also be enabled for expressions if we add runtime align queries
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template<typename ProductType, int LhsOrder, int LhsAccess, int RhsCols>
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struct ei_cache_friendly_product_selector<ProductType,1,LhsOrder,LhsAccess,RhsCols,RowMajor,HasDirectAccess>
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{
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typedef typename ProductType::Scalar Scalar;
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template<typename DestDerived>
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inline static void run(DestDerived& res, const ProductType& product)
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{
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enum {
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EvalToRes = (ei_packet_traits<Scalar>::size==1)
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||(DestDerived::Flags & ActualPacketAccessBit) && (DestDerived::Flags & RowMajorBit) };
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Scalar* __restrict__ _res;
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if (EvalToRes)
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_res = &res.coeffRef(0);
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else
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{
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_res = (Scalar*)alloca(sizeof(Scalar)*res.size());
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Map<Matrix<Scalar,DestDerived::RowsAtCompileTime,1> >(_res, res.size()) = res;
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}
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ei_cache_friendly_product(res.size(),
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&product.rhs().const_cast_derived().coeffRef(0,0), product.rhs().stride(),
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product.lhs().transpose(), _res);
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if (!EvalToRes)
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res = Map<Matrix<Scalar,1,DestDerived::ColsAtCompileTime> >(_res, res.size());
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}
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};
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/** \internal */
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template<typename Derived>
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template<typename Lhs,typename Rhs>
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@ -39,9 +39,13 @@ template<typename MatrixType> void product(const MatrixType& m)
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typedef typename MatrixType::Scalar Scalar;
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typedef typename NumTraits<Scalar>::FloatingPoint FloatingPoint;
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typedef Matrix<Scalar, MatrixType::RowsAtCompileTime, 1> VectorType;
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typedef Matrix<Scalar, MatrixType::RowsAtCompileTime, 1> RowVectorType;
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typedef Matrix<Scalar, MatrixType::ColsAtCompileTime, 1> ColVectorType;
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typedef Matrix<Scalar, MatrixType::RowsAtCompileTime, MatrixType::RowsAtCompileTime> RowSquareMatrixType;
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typedef Matrix<Scalar, MatrixType::ColsAtCompileTime, MatrixType::ColsAtCompileTime> ColSquareMatrixType;
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typedef Matrix<Scalar, MatrixType::RowsAtCompileTime, MatrixType::ColsAtCompileTime,
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MatrixType::RowsAtCompileTime, MatrixType::ColsAtCompileTime,
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MatrixType::Flags&RowMajorBit ? 0 : RowMajorBit> OtherMajorMatrixType;
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int rows = m.rows();
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int cols = m.cols();
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@ -59,9 +63,11 @@ template<typename MatrixType> void product(const MatrixType& m)
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ColSquareMatrixType
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square2 = ColSquareMatrixType::random(cols, cols),
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res2 = ColSquareMatrixType::random(cols, cols);
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VectorType v1 = VectorType::random(rows),
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v2 = VectorType::random(rows),
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vzero = VectorType::zero(rows);
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RowVectorType v1 = RowVectorType::random(rows),
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v2 = RowVectorType::random(rows),
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vzero = RowVectorType::zero(rows);
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ColVectorType vc2 = ColVectorType::random(cols), vcres;
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OtherMajorMatrixType tm1 = m1;
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Scalar s1 = ei_random<Scalar>();
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@ -89,6 +95,7 @@ template<typename MatrixType> void product(const MatrixType& m)
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// test Product.h together with Identity.h
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VERIFY_IS_APPROX(v1, identity*v1);
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VERIFY_IS_APPROX(v1.transpose(), v1.transpose() * identity);
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// again, test operator() to check const-qualification
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VERIFY_IS_APPROX(MatrixType::identity(rows, cols)(r,c), static_cast<Scalar>(r==c));
|
||||
|
||||
@ -110,6 +117,21 @@ template<typename MatrixType> void product(const MatrixType& m)
|
||||
{
|
||||
VERIFY(areNotApprox(res,square + m2 * m1.transpose()));
|
||||
}
|
||||
vcres = vc2;
|
||||
vcres += (m1.transpose() * v1).lazy();
|
||||
VERIFY_IS_APPROX(vcres, vc2 + m1.transpose() * v1);
|
||||
tm1 = m1;
|
||||
VERIFY_IS_APPROX(tm1.transpose() * v1, m1.transpose() * v1);
|
||||
VERIFY_IS_APPROX(v1.transpose() * tm1, v1.transpose() * m1);
|
||||
|
||||
// test submatrix and matrix/vector product
|
||||
for (int i=0; i<rows; ++i)
|
||||
res.row(i) = m1.row(i) * m2.transpose();
|
||||
VERIFY_IS_APPROX(res, m1 * m2.transpose());
|
||||
// the other way round:
|
||||
for (int i=0; i<rows; ++i)
|
||||
res.col(i) = m1 * m2.transpose().col(i);
|
||||
VERIFY_IS_APPROX(res, m1 * m2.transpose());
|
||||
|
||||
res2 = square2;
|
||||
res2 += (m1.transpose() * m2).lazy();
|
||||
|
Loading…
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Reference in New Issue
Block a user