Optimize the product of a householder-sequence with the identity, and optimize the evaluation of a HouseholderSequence to a dense matrix using faster blocked product.
diff --git a/CTestConfig.cmake b/CTestConfig.cmake
index 4c00278..8b4cd79 100644
--- a/CTestConfig.cmake
+++ b/CTestConfig.cmake
@@ -11,7 +11,7 @@
set(CTEST_DROP_SITE "manao.inria.fr")
set(CTEST_DROP_LOCATION "/CDash/submit.php?project=Eigen")
set(CTEST_DROP_SITE_CDASH TRUE)
-set(CTEST_PROJECT_SUBPROJECTS
-Official
-Unsupported
-)
+#set(CTEST_PROJECT_SUBPROJECTS
+#Official
+#Unsupported
+#)
diff --git a/Eigen/src/Householder/HouseholderSequence.h b/Eigen/src/Householder/HouseholderSequence.h
index a4f40b7..af19701 100644
--- a/Eigen/src/Householder/HouseholderSequence.h
+++ b/Eigen/src/Householder/HouseholderSequence.h
@@ -295,6 +295,14 @@
for(Index k = 0; k<cols()-vecs ; ++k)
dst.col(k).tail(rows()-k-1).setZero();
}
+ else if(m_length>BlockSize)
+ {
+ dst.setIdentity(rows(), rows());
+ if(m_reverse)
+ applyThisOnTheLeft(dst,workspace,true);
+ else
+ applyThisOnTheLeft(dst,workspace,true);
+ }
else
{
dst.setIdentity(rows(), rows());
@@ -332,24 +340,27 @@
}
/** \internal */
- template<typename Dest> inline void applyThisOnTheLeft(Dest& dst) const
+ template<typename Dest> inline void applyThisOnTheLeft(Dest& dst, bool inputIsIdentity = false) const
{
Matrix<Scalar,1,Dest::ColsAtCompileTime,RowMajor,1,Dest::MaxColsAtCompileTime> workspace;
- applyThisOnTheLeft(dst, workspace);
+ applyThisOnTheLeft(dst, workspace, inputIsIdentity);
}
/** \internal */
template<typename Dest, typename Workspace>
- inline void applyThisOnTheLeft(Dest& dst, Workspace& workspace) const
+ inline void applyThisOnTheLeft(Dest& dst, Workspace& workspace, bool inputIsIdentity = false) const
{
- const Index BlockSize = 48;
+ if(inputIsIdentity && m_reverse)
+ inputIsIdentity = false;
// if the entries are large enough, then apply the reflectors by block
if(m_length>=BlockSize && dst.cols()>1)
{
- for(Index i = 0; i < m_length; i+=BlockSize)
+ // Make sure we have at least 2 useful blocks, otherwise it is point-less:
+ Index blockSize = m_length<2*BlockSize ? (m_length+1)/2 : BlockSize;
+ for(Index i = 0; i < m_length; i+=blockSize)
{
- Index end = m_reverse ? (std::min)(m_length,i+BlockSize) : m_length-i;
- Index k = m_reverse ? i : (std::max)(Index(0),end-BlockSize);
+ Index end = m_reverse ? (std::min)(m_length,i+blockSize) : m_length-i;
+ Index k = m_reverse ? i : (std::max)(Index(0),end-blockSize);
Index bs = end-k;
Index start = k + m_shift;
@@ -359,7 +370,14 @@
Side==OnTheRight ? bs : m_vectors.rows()-start,
Side==OnTheRight ? m_vectors.cols()-start : bs);
typename internal::conditional<Side==OnTheRight, Transpose<SubVectorsType>, SubVectorsType&>::type sub_vecs(sub_vecs1);
- Block<Dest,Dynamic,Dynamic> sub_dst(dst,dst.rows()-rows()+m_shift+k,0, rows()-m_shift-k,dst.cols());
+
+ Index dstStart = dst.rows()-rows()+m_shift+k;
+ Index dstRows = rows()-m_shift-k;
+ Block<Dest,Dynamic,Dynamic> sub_dst(dst,
+ dstStart,
+ inputIsIdentity ? dstStart : 0,
+ dstRows,
+ inputIsIdentity ? dstRows : dst.cols());
apply_block_householder_on_the_left(sub_dst, sub_vecs, m_coeffs.segment(k, bs), !m_reverse);
}
}
@@ -369,7 +387,8 @@
for(Index k = 0; k < m_length; ++k)
{
Index actual_k = m_reverse ? k : m_length-k-1;
- dst.bottomRows(rows()-m_shift-actual_k)
+ Index dstStart = rows()-m_shift-actual_k;
+ dst.bottomRightCorner(dstStart, inputIsIdentity ? dstStart : dst.cols())
.applyHouseholderOnTheLeft(essentialVector(actual_k), m_coeffs.coeff(actual_k), workspace.data());
}
}
@@ -387,7 +406,7 @@
{
typename internal::matrix_type_times_scalar_type<Scalar, OtherDerived>::Type
res(other.template cast<typename internal::matrix_type_times_scalar_type<Scalar,OtherDerived>::ResultScalar>());
- applyThisOnTheLeft(res);
+ applyThisOnTheLeft(res, internal::is_identity<OtherDerived>::value && res.rows()==res.cols());
return res;
}
@@ -461,6 +480,7 @@
bool m_reverse;
Index m_length;
Index m_shift;
+ enum { BlockSize = 48 };
};
/** \brief Computes the product of a matrix with a Householder sequence.
diff --git a/bench/bench_gemm.cpp b/bench/bench_gemm.cpp
index 8528c55..688d99c 100644
--- a/bench/bench_gemm.cpp
+++ b/bench/bench_gemm.cpp
@@ -129,7 +129,7 @@
template<typename A, typename B, typename C>
EIGEN_DONT_INLINE void gemm(const A& a, const B& b, C& c)
{
- c.noalias() += a * b;
+ c.noalias() += a * b;
}
int main(int argc, char ** argv)
