Replace Eigen block operations with small GEMM and GEMV loops.
1. Add Matrix-Matrix and Matrix-Vector multiply functions.
2. Replace Eigen usage in SchurEliminator with these custom
matrix operations.
3. Save on some memory allocations in ChunkOuterProduct.
4. Replace LDLT with LLT.
As a result on problem-16-22106-pre.txt, the linear solver time
goes down from 1.2s to 0.64s.
Change-Id: I2daa667960e0a1e8834489965a30be31f37fd87f
diff --git a/internal/ceres/CMakeLists.txt b/internal/ceres/CMakeLists.txt
index 4694ec5..8a90935 100644
--- a/internal/ceres/CMakeLists.txt
+++ b/internal/ceres/CMakeLists.txt
@@ -238,6 +238,7 @@
CERES_TEST(array_utils)
CERES_TEST(autodiff)
CERES_TEST(autodiff_cost_function)
+ CERES_TEST(blas)
CERES_TEST(block_random_access_dense_matrix)
CERES_TEST(block_random_access_sparse_matrix)
CERES_TEST(block_sparse_matrix)
diff --git a/internal/ceres/blas.h b/internal/ceres/blas.h
new file mode 100644
index 0000000..028b63a
--- /dev/null
+++ b/internal/ceres/blas.h
@@ -0,0 +1,390 @@
+// Ceres Solver - A fast non-linear least squares minimizer
+// Copyright 2013 Google Inc. All rights reserved.
+// http://code.google.com/p/ceres-solver/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// * Redistributions of source code must retain the above copyright notice,
+// this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above copyright notice,
+// this list of conditions and the following disclaimer in the documentation
+// and/or other materials provided with the distribution.
+// * Neither the name of Google Inc. nor the names of its contributors may be
+// used to endorse or promote products derived from this software without
+// specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+// POSSIBILITY OF SUCH DAMAGE.
+//
+// Author: sameeragarwal@google.com (Sameer Agarwal)
+//
+// Simple blas functions for use in the Schur Eliminator. These are
+// fairly basic implementations which already yield a significant
+// speedup in the eliminator performance.
+
+#ifndef CERES_INTERNAL_BLAS_H_
+#define CERES_INTERNAL_BLAS_H_
+
+#include "ceres/internal/eigen.h"
+#include "glog/logging.h"
+
+namespace ceres {
+namespace internal {
+
+// Remove the ".noalias()" annotation from the matrix matrix
+// mutliplies to produce a correct build with the Android NDK,
+// including versions 6, 7, 8, and 8b, when built with STLPort and the
+// non-standalone toolchain (i.e. ndk-build). This appears to be a
+// compiler bug; if the workaround is not in place, the line
+//
+// block.noalias() -= A * B;
+//
+// gets compiled to
+//
+// block.noalias() += A * B;
+//
+// which breaks schur elimination. Introducing a temporary by removing the
+// .noalias() annotation causes the issue to disappear. Tracking this
+// issue down was tricky, since the test suite doesn't run when built with
+// the non-standalone toolchain.
+//
+// TODO(keir): Make a reproduction case for this and send it upstream.
+#ifdef CERES_WORK_AROUND_ANDROID_NDK_COMPILER_BUG
+#define CERES_MAYBE_NOALIAS
+#else
+#define CERES_MAYBE_NOALIAS .noalias()
+#endif
+
+// C op A * B;
+//
+// where op can be +=, -=, or =.
+//
+// The template parameters (kRowA, kColA, kRowB, kColB) allow
+// specialization of the loop at compile time. If this information is
+// not available, then Eigen::Dynamic should be used as the template
+// argument.
+//
+// kOperation = 1 -> C += A * B
+// kOperation = -1 -> C -= A * B
+// kOperation = 0 -> C = A * B
+//
+// The function can write into matrices C which are larger than the
+// matrix A * B. This is done by specifying the true size of C via
+// row_stride_c and col_stride_c, and then indicating where A * B
+// should be written into by start_row_c and start_col_c.
+//
+// Graphically if row_stride_c = 10, col_stride_c = 12, start_row_c =
+// 4 and start_col_c = 5, then if A = 3x2 and B = 2x4, we get
+//
+// ------------
+// ------------
+// ------------
+// ------------
+// -----xxxx---
+// -----xxxx---
+// -----xxxx---
+// ------------
+// ------------
+// ------------
+//
+template<int kRowA, int kColA, int kRowB, int kColB, int kOperation>
+inline void MatrixMatrixMultiply(const double* A,
+ const int num_row_a,
+ const int num_col_a,
+ const double* B,
+ const int num_row_b,
+ const int num_col_b,
+ double* C,
+ const int start_row_c,
+ const int start_col_c,
+ const int row_stride_c,
+ const int col_stride_c) {
+#ifdef CERES_NO_CUSTOM_BLAS
+ const typename EigenTypes<kRowA, kColA>::ConstMatrixRef Aref(A, num_row_a, num_col_a);
+ const typename EigenTypes<kRowB, kColB>::ConstMatrixRef Bref(B, num_row_b, num_col_b);
+ MatrixRef Cref(C, row_stride_c, col_stride_c);
+ Eigen::Block<MatrixRef, kRowA, kColB> block(Cref,
+ start_row_c, start_col_c,
+ num_row_a, num_col_b);
+
+ if (kOperation > 0) {
+ block CERES_MAYBE_NOALIAS += Aref * Bref;
+ } else if (kOperation < 0) {
+ block CERES_MAYBE_NOALIAS -= Aref * Bref;
+ } else {
+ block CERES_MAYBE_NOALIAS = Aref * Bref;
+ }
+
+#else
+
+ DCHECK_GT(num_row_a, 0);
+ DCHECK_GT(num_col_a, 0);
+ DCHECK_GT(num_row_b, 0);
+ DCHECK_GT(num_col_b, 0);
+ DCHECK_GE(start_row_c, 0);
+ DCHECK_GE(start_col_c, 0);
+ DCHECK_GT(row_stride_c, 0);
+ DCHECK_GT(col_stride_c, 0);
+
+ DCHECK((kRowA == Eigen::Dynamic) || (kRowA == num_row_a));
+ DCHECK((kColA == Eigen::Dynamic) || (kColA == num_col_a));
+ DCHECK((kRowB == Eigen::Dynamic) || (kRowB == num_row_b));
+ DCHECK((kColB == Eigen::Dynamic) || (kColB == num_col_b));
+
+ const int NUM_ROW_A = (kRowA != Eigen::Dynamic ? kRowA : num_row_a);
+ const int NUM_COL_A = (kColA != Eigen::Dynamic ? kColA : num_col_a);
+ const int NUM_ROW_B = (kColB != Eigen::Dynamic ? kRowB : num_row_b);
+ const int NUM_COL_B = (kColB != Eigen::Dynamic ? kColB : num_col_b);
+ DCHECK_EQ(NUM_COL_A, NUM_ROW_B);
+
+ const int NUM_ROW_C = NUM_ROW_A;
+ const int NUM_COL_C = NUM_COL_B;
+ DCHECK_LT(start_row_c + NUM_ROW_C, row_stride_c);
+ DCHECK_LT(start_col_c + NUM_COL_C, col_stride_c);
+
+ for (int row = 0; row < NUM_ROW_C; ++row) {
+ for (int col = 0; col < NUM_COL_C; ++col) {
+ double tmp = 0.0;
+ for (int k = 0; k < NUM_COL_A; ++k) {
+ tmp += A[row * NUM_COL_A + k] * B[k * NUM_COL_B + col];
+ }
+
+ const int index = (row + start_row_c) * col_stride_c + start_col_c + col;
+ if (kOperation > 0) {
+ C[index] += tmp;
+ } else if (kOperation < 0) {
+ C[index] -= tmp;
+ } else {
+ C[index] = tmp;
+ }
+ }
+ }
+#endif // CERES_NO_CUSTOM_BLAS
+}
+
+// C op A' * B;
+//
+// where op can be +=, -=, or =.
+//
+// The template parameters (kRowA, kColA, kRowB, kColB) allow
+// specialization of the loop at compile time. If this information is
+// not available, then Eigen::Dynamic should be used as the template
+// argument.
+//
+// kOperation = 1 -> C += A' * B
+// kOperation = -1 -> C -= A' * B
+// kOperation = 0 -> C = A' * B
+//
+// The function can write into matrices C which are larger than the
+// matrix A' * B. This is done by specifying the true size of C via
+// row_stride_c and col_stride_c, and then indicating where A * B
+// should be written into by start_row_c and start_col_c.
+//
+// Graphically if row_stride_c = 10, col_stride_c = 12, start_row_c =
+// 4 and start_col_c = 5, then if A = 2x3 and B = 2x4, we get
+//
+// ------------
+// ------------
+// ------------
+// ------------
+// -----xxxx---
+// -----xxxx---
+// -----xxxx---
+// ------------
+// ------------
+// ------------
+//
+template<int kRowA, int kColA, int kRowB, int kColB, int kOperation>
+inline void MatrixTransposeMatrixMultiply(const double* A,
+ const int num_row_a,
+ const int num_col_a,
+ const double* B,
+ const int num_row_b,
+ const int num_col_b,
+ double* C,
+ const int start_row_c,
+ const int start_col_c,
+ const int row_stride_c,
+ const int col_stride_c) {
+#ifdef CERES_NO_CUSTOM_BLAS
+ const typename EigenTypes<kRowA, kColA>::ConstMatrixRef Aref(A, num_row_a, num_col_a);
+ const typename EigenTypes<kRowB, kColB>::ConstMatrixRef Bref(B, num_row_b, num_col_b);
+ MatrixRef Cref(C, row_stride_c, col_stride_c);
+ Eigen::Block<MatrixRef, kColA, kColB> block(Cref,
+ start_row_c, start_col_c,
+ num_col_a, num_col_b);
+
+ if (kOperation > 0) {
+ block CERES_MAYBE_NOALIAS += Aref.transpose() * Bref;
+ } else if (kOperation < 0) {
+ block CERES_MAYBE_NOALIAS -= Aref.transpose() * Bref;
+ } else {
+ block CERES_MAYBE_NOALIAS = Aref.transpose() * Bref;
+ }
+
+#else
+
+ DCHECK_GT(num_row_a, 0);
+ DCHECK_GT(num_col_a, 0);
+ DCHECK_GT(num_row_b, 0);
+ DCHECK_GT(num_col_b, 0);
+ DCHECK_GE(start_row_c, 0);
+ DCHECK_GE(start_col_c, 0);
+ DCHECK_GT(row_stride_c, 0);
+ DCHECK_GT(col_stride_c, 0);
+
+ DCHECK((kRowA == Eigen::Dynamic) || (kRowA == num_row_a));
+ DCHECK((kColA == Eigen::Dynamic) || (kColA == num_col_a));
+ DCHECK((kRowB == Eigen::Dynamic) || (kRowB == num_row_b));
+ DCHECK((kColB == Eigen::Dynamic) || (kColB == num_col_b));
+
+ const int NUM_ROW_A = (kRowA != Eigen::Dynamic ? kRowA : num_row_a);
+ const int NUM_COL_A = (kColA != Eigen::Dynamic ? kColA : num_col_a);
+ const int NUM_ROW_B = (kColB != Eigen::Dynamic ? kRowB : num_row_b);
+ const int NUM_COL_B = (kColB != Eigen::Dynamic ? kColB : num_col_b);
+ DCHECK_EQ(NUM_ROW_A, NUM_ROW_B);
+
+ const int NUM_ROW_C = NUM_COL_A;
+ const int NUM_COL_C = NUM_COL_B;
+ DCHECK_LT(start_row_c + NUM_ROW_C, row_stride_c);
+ DCHECK_LT(start_col_c + NUM_COL_C, col_stride_c);
+
+ for (int row = 0; row < NUM_ROW_C; ++row) {
+ for (int col = 0; col < NUM_COL_C; ++col) {
+ double tmp = 0.0;
+ for (int k = 0; k < NUM_ROW_A; ++k) {
+ tmp += A[k * NUM_COL_A + row] * B[k * NUM_COL_B + col];
+ }
+
+ const int index = (row + start_row_c) * col_stride_c + start_col_c + col;
+ if (kOperation > 0) {
+ C[index]+= tmp;
+ } else if (kOperation < 0) {
+ C[index]-= tmp;
+ } else {
+ C[index]= tmp;
+ }
+ }
+ }
+#endif // CERES_NO_CUSTOM_BLAS
+}
+
+template<int kRowA, int kColA, int kOperation>
+inline void MatrixVectorMultiply(const double* A,
+ const int num_row_a,
+ const int num_col_a,
+ const double* b,
+ double* c) {
+#ifdef CERES_NO_CUSTOM_BLAS
+ const typename EigenTypes<kRowA, kColA>::ConstMatrixRef Aref(A, num_row_a, num_col_a);
+ const typename EigenTypes<kColA>::ConstVectorRef bref(b, num_col_a);
+ typename EigenTypes<kRowA>::VectorRef cref(c, num_row_a);
+
+ if (kOperation > 0) {
+ cref.noalias() += Aref * bref;
+ } else if (kOperation < 0) {
+ cref.noalias() -= Aref * bref;
+ } else {
+ cref.noalias() = Aref * bref;
+ }
+
+#else
+
+ DCHECK_GT(num_row_a, 0);
+ DCHECK_GT(num_col_a, 0);
+ DCHECK((kRowA == Eigen::Dynamic) || (kRowA == num_row_a));
+ DCHECK((kColA == Eigen::Dynamic) || (kColA == num_col_a));
+
+ const int NUM_ROW_A = (kRowA != Eigen::Dynamic ? kRowA : num_row_a);
+ const int NUM_COL_A = (kColA != Eigen::Dynamic ? kColA : num_col_a);
+
+ for (int row = 0; row < NUM_ROW_A; ++row) {
+ double tmp = 0.0;
+ for (int col = 0; col < NUM_COL_A; ++col) {
+ tmp += A[row * NUM_COL_A + col] * b[col];
+ }
+
+ if (kOperation > 0) {
+ c[row] += tmp;
+ } else if (kOperation < 0) {
+ c[row] -= tmp;
+ } else {
+ c[row] = tmp;
+ }
+ }
+#endif // CERES_NO_CUSTOM_BLAS
+}
+
+// c op A' * b;
+//
+// where op can be +=, -=, or =.
+//
+// The template parameters (kRowA, kColA) allow specialization of the
+// loop at compile time. If this information is not available, then
+// Eigen::Dynamic should be used as the template argument.
+//
+// kOperation = 1 -> c += A' * b
+// kOperation = -1 -> c -= A' * b
+// kOperation = 0 -> c = A' * b
+template<int kRowA, int kColA, int kOperation>
+inline void MatrixTransposeVectorMultiply(const double* A,
+ const int num_row_a,
+ const int num_col_a,
+ const double* b,
+ double* c) {
+#ifdef CERES_NO_CUSTOM_BLAS
+ const typename EigenTypes<kRowA, kColA>::ConstMatrixRef Aref(A, num_row_a, num_col_a);
+ const typename EigenTypes<kRowA>::ConstVectorRef bref(b, num_row_a);
+ typename EigenTypes<kColA>::VectorRef cref(c, num_col_a);
+
+ if (kOperation > 0) {
+ cref.noalias() += Aref.transpose() * bref;
+ } else if (kOperation < 0) {
+ cref.noalias() -= Aref.transpose() * bref;
+ } else {
+ cref.noalias() = Aref.transpose() * bref;
+ }
+
+#else
+
+ DCHECK_GT(num_row_a, 0);
+ DCHECK_GT(num_col_a, 0);
+ DCHECK((kRowA == Eigen::Dynamic) || (kRowA == num_row_a));
+ DCHECK((kColA == Eigen::Dynamic) || (kColA == num_col_a));
+
+ const int NUM_ROW_A = (kRowA != Eigen::Dynamic ? kRowA : num_row_a);
+ const int NUM_COL_A = (kColA != Eigen::Dynamic ? kColA : num_col_a);
+
+ for (int row = 0; row < NUM_COL_A; ++row) {
+ double tmp = 0.0;
+ for (int col = 0; col < NUM_ROW_A; ++col) {
+ tmp += A[col * NUM_COL_A + row] * b[col];
+ }
+
+ if (kOperation > 0) {
+ c[row] += tmp;
+ } else if (kOperation < 0) {
+ c[row] -= tmp;
+ } else {
+ c[row] = tmp;
+ }
+ }
+#endif // CERES_NO_CUSTOM_BLAS
+}
+
+#undef CERES_MAYBE_NOALIAS
+
+} // namespace internal
+} // namespace ceres
+
+#endif // CERES_INTERNAL_BLAS_H_
diff --git a/internal/ceres/blas_test.cc b/internal/ceres/blas_test.cc
new file mode 100644
index 0000000..efa7e7b
--- /dev/null
+++ b/internal/ceres/blas_test.cc
@@ -0,0 +1,303 @@
+// Ceres Solver - A fast non-linear least squares minimizer
+// Copyright 2013 Google Inc. All rights reserved.
+// http://code.google.com/p/ceres-solver/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// * Redistributions of source code must retain the above copyright notice,
+// this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above copyright notice,
+// this list of conditions and the following disclaimer in the documentation
+// and/or other materials provided with the distribution.
+// * Neither the name of Google Inc. nor the names of its contributors may be
+// used to endorse or promote products derived from this software without
+// specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+// POSSIBILITY OF SUCH DAMAGE.
+//
+// Author: keir@google.com (Keir Mierle)
+
+#include "ceres/blas.h"
+
+#include "gtest/gtest.h"
+#include "ceres/internal/eigen.h"
+
+namespace ceres {
+namespace internal {
+
+TEST(BLAS, MatrixMatrixMultiply) {
+ const double kTolerance = 1e-16;
+ const int kRowA = 3;
+ const int kColA = 5;
+ Matrix A(kRowA, kColA);
+ A.setOnes();
+
+ const int kRowB = 5;
+ const int kColB = 7;
+ Matrix B(kRowB, kColB);
+ B.setOnes();
+
+ for (int row_stride_c = kRowA; row_stride_c < 3 * kRowA; ++row_stride_c) {
+ for (int col_stride_c = kColB; col_stride_c < 3 * kColB; ++col_stride_c) {
+ Matrix C(row_stride_c, col_stride_c);
+ C.setOnes();
+
+ Matrix C_plus = C;
+ Matrix C_minus = C;
+ Matrix C_assign = C;
+
+ Matrix C_plus_ref = C;
+ Matrix C_minus_ref = C;
+ Matrix C_assign_ref = C;
+ for (int start_row_c = 0; start_row_c + kRowA < row_stride_c; ++start_row_c) {
+ for (int start_col_c = 0; start_col_c + kColB < col_stride_c; ++start_col_c) {
+ C_plus_ref.block(start_row_c, start_col_c, kRowA, kColB) +=
+ A * B;
+
+ MatrixMatrixMultiply<kRowA, kColA, kRowB, kColB, 1>(
+ A.data(), kRowA, kColA,
+ B.data(), kRowB, kColB,
+ C_plus.data(), start_row_c, start_col_c, row_stride_c, col_stride_c);
+
+ EXPECT_NEAR((C_plus_ref - C_plus).norm(), 0.0, kTolerance)
+ << "C += A * B \n"
+ << "row_stride_c : " << row_stride_c << "\n"
+ << "col_stride_c : " << col_stride_c << "\n"
+ << "start_row_c : " << start_row_c << "\n"
+ << "start_col_c : " << start_col_c << "\n"
+ << "Cref : \n" << C_plus_ref << "\n"
+ << "C: \n" << C_plus;
+
+
+ C_minus_ref.block(start_row_c, start_col_c, kRowA, kColB) -=
+ A * B;
+
+ MatrixMatrixMultiply<kRowA, kColA, kRowB, kColB, -1>(
+ A.data(), kRowA, kColA,
+ B.data(), kRowB, kColB,
+ C_minus.data(), start_row_c, start_col_c, row_stride_c, col_stride_c);
+
+ EXPECT_NEAR((C_minus_ref - C_minus).norm(), 0.0, kTolerance)
+ << "C -= A * B \n"
+ << "row_stride_c : " << row_stride_c << "\n"
+ << "col_stride_c : " << col_stride_c << "\n"
+ << "start_row_c : " << start_row_c << "\n"
+ << "start_col_c : " << start_col_c << "\n"
+ << "Cref : \n" << C_minus_ref << "\n"
+ << "C: \n" << C_minus;
+
+ C_assign_ref.block(start_row_c, start_col_c, kRowA, kColB) =
+ A * B;
+
+ MatrixMatrixMultiply<kRowA, kColA, kRowB, kColB, 0>(
+ A.data(), kRowA, kColA,
+ B.data(), kRowB, kColB,
+ C_assign.data(), start_row_c, start_col_c, row_stride_c, col_stride_c);
+
+ EXPECT_NEAR((C_assign_ref - C_assign).norm(), 0.0, kTolerance)
+ << "C = A * B \n"
+ << "row_stride_c : " << row_stride_c << "\n"
+ << "col_stride_c : " << col_stride_c << "\n"
+ << "start_row_c : " << start_row_c << "\n"
+ << "start_col_c : " << start_col_c << "\n"
+ << "Cref : \n" << C_assign_ref << "\n"
+ << "C: \n" << C_assign;
+ }
+ }
+ }
+ }
+}
+
+TEST(BLAS, MatrixTransposeMatrixMultiply) {
+ const double kTolerance = 1e-16;
+ const int kRowA = 5;
+ const int kColA = 3;
+ Matrix A(kRowA, kColA);
+ A.setOnes();
+
+ const int kRowB = 5;
+ const int kColB = 7;
+ Matrix B(kRowB, kColB);
+ B.setOnes();
+
+ for (int row_stride_c = kColA; row_stride_c < 3 * kColA; ++row_stride_c) {
+ for (int col_stride_c = kColB; col_stride_c < 3 * kColB; ++col_stride_c) {
+ Matrix C(row_stride_c, col_stride_c);
+ C.setOnes();
+
+ Matrix C_plus = C;
+ Matrix C_minus = C;
+ Matrix C_assign = C;
+
+ Matrix C_plus_ref = C;
+ Matrix C_minus_ref = C;
+ Matrix C_assign_ref = C;
+ for (int start_row_c = 0; start_row_c + kColA < row_stride_c; ++start_row_c) {
+ for (int start_col_c = 0; start_col_c + kColB < col_stride_c; ++start_col_c) {
+ C_plus_ref.block(start_row_c, start_col_c, kColA, kColB) +=
+ A.transpose() * B;
+
+ MatrixTransposeMatrixMultiply<kRowA, kColA, kRowB, kColB, 1>(
+ A.data(), kRowA, kColA,
+ B.data(), kRowB, kColB,
+ C_plus.data(), start_row_c, start_col_c, row_stride_c, col_stride_c);
+
+ EXPECT_NEAR((C_plus_ref - C_plus).norm(), 0.0, kTolerance)
+ << "C += A' * B \n"
+ << "row_stride_c : " << row_stride_c << "\n"
+ << "col_stride_c : " << col_stride_c << "\n"
+ << "start_row_c : " << start_row_c << "\n"
+ << "start_col_c : " << start_col_c << "\n"
+ << "Cref : \n" << C_plus_ref << "\n"
+ << "C: \n" << C_plus;
+
+ C_minus_ref.block(start_row_c, start_col_c, kColA, kColB) -=
+ A.transpose() * B;
+
+ MatrixTransposeMatrixMultiply<kRowA, kColA, kRowB, kColB, -1>(
+ A.data(), kRowA, kColA,
+ B.data(), kRowB, kColB,
+ C_minus.data(), start_row_c, start_col_c, row_stride_c, col_stride_c);
+
+ EXPECT_NEAR((C_minus_ref - C_minus).norm(), 0.0, kTolerance)
+ << "C -= A' * B \n"
+ << "row_stride_c : " << row_stride_c << "\n"
+ << "col_stride_c : " << col_stride_c << "\n"
+ << "start_row_c : " << start_row_c << "\n"
+ << "start_col_c : " << start_col_c << "\n"
+ << "Cref : \n" << C_minus_ref << "\n"
+ << "C: \n" << C_minus;
+
+ C_assign_ref.block(start_row_c, start_col_c, kColA, kColB) =
+ A.transpose() * B;
+
+ MatrixTransposeMatrixMultiply<kRowA, kColA, kRowB, kColB, 0>(
+ A.data(), kRowA, kColA,
+ B.data(), kRowB, kColB,
+ C_assign.data(), start_row_c, start_col_c, row_stride_c, col_stride_c);
+
+ EXPECT_NEAR((C_assign_ref - C_assign).norm(), 0.0, kTolerance)
+ << "C = A' * B \n"
+ << "row_stride_c : " << row_stride_c << "\n"
+ << "col_stride_c : " << col_stride_c << "\n"
+ << "start_row_c : " << start_row_c << "\n"
+ << "start_col_c : " << start_col_c << "\n"
+ << "Cref : \n" << C_assign_ref << "\n"
+ << "C: \n" << C_assign;
+ }
+ }
+ }
+ }
+}
+
+TEST(BLAS, MatrixVectorMultiply) {
+ const double kTolerance = 1e-16;
+ const int kRowA = 5;
+ const int kColA = 3;
+ Matrix A(kRowA, kColA);
+ A.setOnes();
+
+ Vector b(kColA);
+ b.setOnes();
+
+ Vector c(kRowA);
+ c.setOnes();
+
+ Vector c_plus = c;
+ Vector c_minus = c;
+ Vector c_assign = c;
+
+ Vector c_plus_ref = c;
+ Vector c_minus_ref = c;
+ Vector c_assign_ref = c;
+
+ c_plus_ref += A * b;
+ MatrixVectorMultiply<kRowA, kColA, 1>(A.data(), kRowA, kColA,
+ b.data(),
+ c_plus.data());
+ EXPECT_NEAR((c_plus_ref - c_plus).norm(), 0.0, kTolerance)
+ << "c += A * b \n"
+ << "c_ref : \n" << c_plus_ref << "\n"
+ << "c: \n" << c_plus;
+
+ c_minus_ref -= A * b;
+ MatrixVectorMultiply<kRowA, kColA, -1>(A.data(), kRowA, kColA,
+ b.data(),
+ c_minus.data());
+ EXPECT_NEAR((c_minus_ref - c_minus).norm(), 0.0, kTolerance)
+ << "c += A * b \n"
+ << "c_ref : \n" << c_minus_ref << "\n"
+ << "c: \n" << c_minus;
+
+ c_assign_ref = A * b;
+ MatrixVectorMultiply<kRowA, kColA, 0>(A.data(), kRowA, kColA,
+ b.data(),
+ c_assign.data());
+ EXPECT_NEAR((c_assign_ref - c_assign).norm(), 0.0, kTolerance)
+ << "c += A * b \n"
+ << "c_ref : \n" << c_assign_ref << "\n"
+ << "c: \n" << c_assign;
+}
+
+TEST(BLAS, MatrixTransposeVectorMultiply) {
+ const double kTolerance = 1e-16;
+ const int kRowA = 5;
+ const int kColA = 3;
+ Matrix A(kRowA, kColA);
+ A.setRandom();
+
+ Vector b(kRowA);
+ b.setRandom();
+
+ Vector c(kColA);
+ c.setOnes();
+
+ Vector c_plus = c;
+ Vector c_minus = c;
+ Vector c_assign = c;
+
+ Vector c_plus_ref = c;
+ Vector c_minus_ref = c;
+ Vector c_assign_ref = c;
+
+ c_plus_ref += A.transpose() * b;
+ MatrixTransposeVectorMultiply<kRowA, kColA, 1>(A.data(), kRowA, kColA,
+ b.data(),
+ c_plus.data());
+ EXPECT_NEAR((c_plus_ref - c_plus).norm(), 0.0, kTolerance)
+ << "c += A' * b \n"
+ << "c_ref : \n" << c_plus_ref << "\n"
+ << "c: \n" << c_plus;
+
+ c_minus_ref -= A.transpose() * b;
+ MatrixTransposeVectorMultiply<kRowA, kColA, -1>(A.data(), kRowA, kColA,
+ b.data(),
+ c_minus.data());
+ EXPECT_NEAR((c_minus_ref - c_minus).norm(), 0.0, kTolerance)
+ << "c += A' * b \n"
+ << "c_ref : \n" << c_minus_ref << "\n"
+ << "c: \n" << c_minus;
+
+ c_assign_ref = A.transpose() * b;
+ MatrixTransposeVectorMultiply<kRowA, kColA, 0>(A.data(), kRowA, kColA,
+ b.data(),
+ c_assign.data());
+ EXPECT_NEAR((c_assign_ref - c_assign).norm(), 0.0, kTolerance)
+ << "c += A' * b \n"
+ << "c_ref : \n" << c_assign_ref << "\n"
+ << "c: \n" << c_assign;
+}
+
+} // namespace internal
+} // namespace ceres
diff --git a/internal/ceres/schur_eliminator.h b/internal/ceres/schur_eliminator.h
index 877621b..e0c7fda 100644
--- a/internal/ceres/schur_eliminator.h
+++ b/internal/ceres/schur_eliminator.h
@@ -321,9 +321,25 @@
// see the documentation of the Chunk object above.
vector<Chunk> chunks_;
+ // TODO(sameeragarwal): The following two arrays contain per-thread
+ // storage. They should be refactored into a per thread struct.
+
// Buffer to store the products of the y and z blocks generated
- // during the elimination phase.
+ // during the elimination phase. buffer_ is of size num_threads *
+ // buffer_size_. Each thread accesses the chunk
+ //
+ // [thread_id * buffer_size_ , (thread_id + 1) * buffer_size_]
+ //
scoped_array<double> buffer_;
+
+ // Buffer to store per thread matrix matrix products used by
+ // ChunkOuterProduct. Like buffer_ it is of size num_threads *
+ // buffer_size_. Each thread accesses the chunk
+ //
+ // [thread_id * buffer_size_ , (thread_id + 1) * buffer_size_]
+ //
+ scoped_array<double> chunk_outer_product_buffer_;
+
int buffer_size_;
int num_threads_;
int uneliminated_row_begins_;
diff --git a/internal/ceres/schur_eliminator_impl.h b/internal/ceres/schur_eliminator_impl.h
index 339c44b..b46eab9 100644
--- a/internal/ceres/schur_eliminator_impl.h
+++ b/internal/ceres/schur_eliminator_impl.h
@@ -34,10 +34,6 @@
#ifndef CERES_INTERNAL_SCHUR_ELIMINATOR_IMPL_H_
#define CERES_INTERNAL_SCHUR_ELIMINATOR_IMPL_H_
-#ifdef CERES_USE_OPENMP
-#include <omp.h>
-#endif
-
// Eigen has an internal threshold switching between different matrix
// multiplication algorithms. In particular for matrices larger than
// EIGEN_CACHEFRIENDLY_PRODUCT_THRESHOLD it uses a cache friendly
@@ -46,19 +42,25 @@
// are thin and long, the default choice may not be optimal. This is
// the case for us, as the default choice causes a 30% performance
// regression when we moved from Eigen2 to Eigen3.
+
#define EIGEN_CACHEFRIENDLY_PRODUCT_THRESHOLD 10
+#ifdef CERES_USE_OPENMP
+#include <omp.h>
+#endif
+
#include <algorithm>
#include <map>
#include "Eigen/Dense"
+#include "ceres/blas.h"
#include "ceres/block_random_access_matrix.h"
#include "ceres/block_sparse_matrix.h"
#include "ceres/block_structure.h"
+#include "ceres/internal/eigen.h"
+#include "ceres/internal/scoped_ptr.h"
#include "ceres/map_util.h"
#include "ceres/schur_eliminator.h"
#include "ceres/stl_util.h"
-#include "ceres/internal/eigen.h"
-#include "ceres/internal/scoped_ptr.h"
#include "glog/logging.h"
namespace ceres {
@@ -149,13 +151,16 @@
buffer_.reset(new double[buffer_size_ * num_threads_]);
+ // chunk_outer_product_buffer_ only needs to store e_block_size *
+ // f_block_size, which is always less than buffer_size_, so we just
+ // allocate buffer_size_ per thread.
+ chunk_outer_product_buffer_.reset(new double[buffer_size_ * num_threads_]);
+
STLDeleteElements(&rhs_locks_);
rhs_locks_.resize(num_col_blocks - num_eliminate_blocks_);
for (int i = 0; i < num_col_blocks - num_eliminate_blocks_; ++i) {
rhs_locks_[i] = new Mutex;
}
-
- VLOG(1) << "Eliminator threads: " << num_threads_;
}
template <int kRowBlockSize, int kEBlockSize, int kFBlockSize>
@@ -261,7 +266,7 @@
typename EigenTypes<kEBlockSize, kEBlockSize>::Matrix inverse_ete =
ete
.template selfadjointView<Eigen::Upper>()
- .ldlt()
+ .llt()
.solve(Matrix::Identity(e_block_size, e_block_size));
// For the current chunk compute and update the rhs of the reduced
@@ -294,8 +299,8 @@
const int e_block_id = bs->rows[chunk.start].cells.front().block_id;
const int e_block_size = bs->cols[e_block_id].size;
- typename EigenTypes<kEBlockSize>::VectorRef y_block(
- y + bs->cols[e_block_id].position, e_block_size);
+ double* y_ptr = y + bs->cols[e_block_id].position;
+ typename EigenTypes<kEBlockSize>::VectorRef y_block(y_ptr, e_block_size);
typename EigenTypes<kEBlockSize, kEBlockSize>::Matrix
ete(e_block_size, e_block_size);
@@ -312,40 +317,35 @@
const double* row_values = A->RowBlockValues(chunk.start + j);
const Cell& e_cell = row.cells.front();
DCHECK_EQ(e_block_id, e_cell.block_id);
- const typename EigenTypes<kRowBlockSize, kEBlockSize>::ConstMatrixRef
- e_block(row_values + e_cell.position,
- row.block.size,
- e_block_size);
- typename EigenTypes<kRowBlockSize>::Vector
- sj =
+ typename EigenTypes<kRowBlockSize>::Vector sj =
typename EigenTypes<kRowBlockSize>::ConstVectorRef
- (b + bs->rows[chunk.start + j].block.position,
- row.block.size);
+ (b + bs->rows[chunk.start + j].block.position, row.block.size);
for (int c = 1; c < row.cells.size(); ++c) {
const int f_block_id = row.cells[c].block_id;
const int f_block_size = bs->cols[f_block_id].size;
- const typename EigenTypes<kRowBlockSize, kFBlockSize>::ConstMatrixRef
- f_block(row_values + row.cells[c].position,
- row.block.size, f_block_size);
const int r_block = f_block_id - num_eliminate_blocks_;
- sj -= f_block *
- typename EigenTypes<kFBlockSize>::ConstVectorRef
- (z + lhs_row_layout_[r_block], f_block_size);
+ MatrixVectorMultiply<kRowBlockSize, kFBlockSize, -1>(
+ row_values + row.cells[c].position, row.block.size, f_block_size,
+ z + lhs_row_layout_[r_block],
+ sj.data());
}
- y_block += e_block.transpose() * sj;
- ete.template selfadjointView<Eigen::Upper>()
- .rankUpdate(e_block.transpose(), 1.0);
+ MatrixTransposeVectorMultiply<kRowBlockSize, kEBlockSize, 1>(
+ row_values + e_cell.position, row.block.size, e_block_size,
+ sj.data(),
+ y_ptr);
+
+ MatrixTransposeMatrixMultiply
+ <kRowBlockSize, kEBlockSize,kRowBlockSize, kEBlockSize, 1>(
+ row_values + e_cell.position, row.block.size, e_block_size,
+ row_values + e_cell.position, row.block.size, e_block_size,
+ ete.data(), 0, 0, e_block_size, e_block_size);
}
- y_block =
- ete
- .template selfadjointView<Eigen::Upper>()
- .ldlt()
- .solve(y_block);
+ ete.llt().solveInPlace(y_block);
}
}
@@ -382,15 +382,12 @@
for (int c = 1; c < row.cells.size(); ++c) {
const int block_id = row.cells[c].block_id;
const int block_size = bs->cols[block_id].size;
- const typename EigenTypes<kRowBlockSize, kFBlockSize>::ConstMatrixRef
- b(row_values + row.cells[c].position,
- row.block.size, block_size);
-
const int block = block_id - num_eliminate_blocks_;
CeresMutexLock l(rhs_locks_[block]);
- typename EigenTypes<kFBlockSize>::VectorRef
- (rhs + lhs_row_layout_[block], block_size).noalias()
- += b.transpose() * sj;
+ MatrixTransposeVectorMultiply<kRowBlockSize, kFBlockSize, 1>(
+ row_values + row.cells[c].position,
+ row.block.size, block_size,
+ sj.data(), rhs + lhs_row_layout_[block]);
}
b_pos += row.block.size;
}
@@ -446,34 +443,31 @@
// Extract the e_block, ETE += E_i' E_i
const Cell& e_cell = row.cells.front();
- const typename EigenTypes<kRowBlockSize, kEBlockSize>::ConstMatrixRef
- e_block(row_values + e_cell.position,
- row.block.size,
- e_block_size);
-
- ete->template selfadjointView<Eigen::Upper>()
- .rankUpdate(e_block.transpose(), 1.0);
+ MatrixTransposeMatrixMultiply
+ <kRowBlockSize, kEBlockSize, kRowBlockSize, kEBlockSize, 1>(
+ row_values + e_cell.position, row.block.size, e_block_size,
+ row_values + e_cell.position, row.block.size, e_block_size,
+ ete->data(), 0, 0, e_block_size, e_block_size);
// g += E_i' b_i
- g->noalias() += e_block.transpose() *
- typename EigenTypes<kRowBlockSize>::ConstVectorRef
- (b + b_pos, row.block.size);
+ MatrixTransposeVectorMultiply<kRowBlockSize, kEBlockSize, 1>(
+ row_values + e_cell.position, row.block.size, e_block_size,
+ b + b_pos,
+ g->data());
+
// buffer = E'F. This computation is done by iterating over the
// f_blocks for each row in the chunk.
for (int c = 1; c < row.cells.size(); ++c) {
const int f_block_id = row.cells[c].block_id;
const int f_block_size = bs->cols[f_block_id].size;
- const typename EigenTypes<kRowBlockSize, kFBlockSize>::ConstMatrixRef
- f_block(row_values + row.cells[c].position,
- row.block.size, f_block_size);
-
double* buffer_ptr =
buffer + FindOrDie(chunk.buffer_layout, f_block_id);
-
- typename EigenTypes<kEBlockSize, kFBlockSize>::MatrixRef
- (buffer_ptr, e_block_size, f_block_size).noalias()
- += e_block.transpose() * f_block;
+ MatrixTransposeMatrixMultiply
+ <kRowBlockSize, kEBlockSize, kRowBlockSize, kFBlockSize, 1>(
+ row_values + e_cell.position, row.block.size, e_block_size,
+ row_values + row.cells[c].position, row.block.size, f_block_size,
+ buffer_ptr, 0, 0, e_block_size, f_block_size);
}
b_pos += row.block.size;
}
@@ -497,15 +491,24 @@
// references to the left hand side.
const int e_block_size = inverse_ete.rows();
BufferLayoutType::const_iterator it1 = buffer_layout.begin();
+
+#ifdef CERES_USE_OPENMP
+ int thread_id = omp_get_thread_num();
+#else
+ int thread_id = 0;
+#endif
+ double* b1_transpose_inverse_ete =
+ chunk_outer_product_buffer_.get() + thread_id * buffer_size_;
+
// S(i,j) -= bi' * ete^{-1} b_j
for (; it1 != buffer_layout.end(); ++it1) {
const int block1 = it1->first - num_eliminate_blocks_;
const int block1_size = bs->cols[it1->first].size;
-
- const typename EigenTypes<kEBlockSize, kFBlockSize>::ConstMatrixRef
- b1(buffer + it1->second, e_block_size, block1_size);
- const typename EigenTypes<kFBlockSize, kEBlockSize>::Matrix
- b1_transpose_inverse_ete = b1.transpose() * inverse_ete;
+ MatrixTransposeMatrixMultiply
+ <kEBlockSize, kFBlockSize, kEBlockSize, kEBlockSize, 0>(
+ buffer + it1->second, e_block_size, block1_size,
+ inverse_ete.data(), e_block_size, e_block_size,
+ b1_transpose_inverse_ete, 0, 0, block1_size, e_block_size);
BufferLayoutType::const_iterator it2 = it1;
for (; it2 != buffer_layout.end(); ++it2) {
@@ -515,46 +518,15 @@
CellInfo* cell_info = lhs->GetCell(block1, block2,
&r, &c,
&row_stride, &col_stride);
- if (cell_info == NULL) {
- continue;
+ if (cell_info != NULL) {
+ const int block2_size = bs->cols[it2->first].size;
+ CeresMutexLock l(&cell_info->m);
+ MatrixMatrixMultiply
+ <kFBlockSize, kEBlockSize, kEBlockSize, kFBlockSize, -1>(
+ b1_transpose_inverse_ete, block1_size, e_block_size,
+ buffer + it2->second, e_block_size, block2_size,
+ cell_info->values, r, c, row_stride, col_stride);
}
-
- const int block2_size = bs->cols[it2->first].size;
- const typename EigenTypes<kEBlockSize, kFBlockSize>::ConstMatrixRef
- b2(buffer + it2->second, e_block_size, block2_size);
-
- CeresMutexLock l(&cell_info->m);
- MatrixRef m(cell_info->values, row_stride, col_stride);
-
- // We explicitly construct a block object here instead of using
- // m.block(), as m.block() variant of the constructor does not
- // allow mixing of template sizing and runtime sizing parameters
- // like the Matrix class does.
- Eigen::Block<MatrixRef, kFBlockSize, kFBlockSize>
- block(m, r, c, block1_size, block2_size);
-#ifdef CERES_WORK_AROUND_ANDROID_NDK_COMPILER_BUG
- // Removing the ".noalias()" annotation on the following statement is
- // necessary to produce a correct build with the Android NDK, including
- // versions 6, 7, 8, and 8b, when built with STLPort and the
- // non-standalone toolchain (i.e. ndk-build). This appears to be a
- // compiler bug; if the workaround is not in place, the line
- //
- // block.noalias() -= b1_transpose_inverse_ete * b2;
- //
- // gets compiled to
- //
- // block.noalias() += b1_transpose_inverse_ete * b2;
- //
- // which breaks schur elimination. Introducing a temporary by removing the
- // .noalias() annotation causes the issue to disappear. Tracking this
- // issue down was tricky, since the test suite doesn't run when built with
- // the non-standalone toolchain.
- //
- // TODO(keir): Make a reproduction case for this and send it upstream.
- block -= b1_transpose_inverse_ete * b2;
-#else
- block.noalias() -= b1_transpose_inverse_ete * b2;
-#endif // CERES_WORK_AROUND_ANDROID_NDK_COMPILER_BUG
}
}
}
@@ -624,10 +596,13 @@
&row_stride, &col_stride);
if (cell_info != NULL) {
CeresMutexLock l(&cell_info->m);
- MatrixRef m(cell_info->values, row_stride, col_stride);
- m.block(r, c, block1_size, block1_size)
- .selfadjointView<Eigen::Upper>()
- .rankUpdate(b1.transpose(), 1.0);
+ // This multiply currently ignores the fact that this is a
+ // symmetric outer product.
+ MatrixTransposeMatrixMultiply
+ <Eigen::Dynamic, Eigen::Dynamic, Eigen::Dynamic, Eigen::Dynamic, 1>(
+ row_values + row.cells[i].position, row.block.size, block1_size,
+ row_values + row.cells[i].position, row.block.size, block1_size,
+ cell_info->values, r, c, row_stride, col_stride);
}
for (int j = i + 1; j < row.cells.size(); ++j) {
@@ -638,17 +613,15 @@
CellInfo* cell_info = lhs->GetCell(block1, block2,
&r, &c,
&row_stride, &col_stride);
- if (cell_info == NULL) {
- continue;
+ if (cell_info != NULL) {
+ const int block2_size = bs->cols[row.cells[j].block_id].size;
+ CeresMutexLock l(&cell_info->m);
+ MatrixTransposeMatrixMultiply
+ <Eigen::Dynamic, Eigen::Dynamic, Eigen::Dynamic, Eigen::Dynamic, 1>(
+ row_values + row.cells[i].position, row.block.size, block1_size,
+ row_values + row.cells[j].position, row.block.size, block2_size,
+ cell_info->values, r, c, row_stride, col_stride);
}
-
- const int block2_size = bs->cols[row.cells[j].block_id].size;
- CeresMutexLock l(&cell_info->m);
- MatrixRef m(cell_info->values, row_stride, col_stride);
- m.block(r, c, block1_size, block2_size).noalias() +=
- b1.transpose() * ConstMatrixRef(row_values + row.cells[j].position,
- row.block.size,
- block2_size);
}
}
}
@@ -670,25 +643,18 @@
DCHECK_GE(block1, 0);
const int block1_size = bs->cols[row.cells[i].block_id].size;
- const typename EigenTypes<kRowBlockSize, kFBlockSize>::ConstMatrixRef
- b1(row_values + row.cells[i].position,
- row.block.size, block1_size);
- {
- int r, c, row_stride, col_stride;
- CellInfo* cell_info = lhs->GetCell(block1, block1,
- &r, &c,
- &row_stride, &col_stride);
- if (cell_info == NULL) {
- continue;
- }
-
+ int r, c, row_stride, col_stride;
+ CellInfo* cell_info = lhs->GetCell(block1, block1,
+ &r, &c,
+ &row_stride, &col_stride);
+ if (cell_info != NULL) {
CeresMutexLock l(&cell_info->m);
- MatrixRef m(cell_info->values, row_stride, col_stride);
-
- Eigen::Block<MatrixRef, kFBlockSize, kFBlockSize>
- block(m, r, c, block1_size, block1_size);
- block.template selfadjointView<Eigen::Upper>()
- .rankUpdate(b1.transpose(), 1.0);
+ // block += b1.transpose() * b1;
+ MatrixTransposeMatrixMultiply
+ <kRowBlockSize, kFBlockSize, kRowBlockSize, kFBlockSize, 1>(
+ row_values + row.cells[i].position, row.block.size, block1_size,
+ row_values + row.cells[i].position, row.block.size, block1_size,
+ cell_info->values, r, c, row_stride, col_stride);
}
for (int j = i + 1; j < row.cells.size(); ++j) {
@@ -700,20 +666,14 @@
CellInfo* cell_info = lhs->GetCell(block1, block2,
&r, &c,
&row_stride, &col_stride);
- if (cell_info == NULL) {
- continue;
+ if (cell_info != NULL) {
+ // block += b1.transpose() * b2;
+ MatrixTransposeMatrixMultiply
+ <kRowBlockSize, kFBlockSize, kRowBlockSize, kFBlockSize, 1>(
+ row_values + row.cells[i].position, row.block.size, block1_size,
+ row_values + row.cells[j].position, row.block.size, block2_size,
+ cell_info->values, r, c, row_stride, col_stride);
}
-
- const typename EigenTypes<kRowBlockSize, kFBlockSize>::ConstMatrixRef
- b2(row_values + row.cells[j].position,
- row.block.size,
- block2_size);
-
- CeresMutexLock l(&cell_info->m);
- MatrixRef m(cell_info->values, row_stride, col_stride);
- Eigen::Block<MatrixRef, kFBlockSize, kFBlockSize>
- block(m, r, c, block1_size, block2_size);
- block.noalias() += b1.transpose() * b2;
}
}
}