|  | // 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_SMALL_BLAS_H_ | 
|  | #define CERES_INTERNAL_SMALL_BLAS_H_ | 
|  |  | 
|  | #include "ceres/internal/port.h" | 
|  | #include "ceres/internal/eigen.h" | 
|  | #include "glog/logging.h" | 
|  |  | 
|  | namespace ceres { | 
|  | namespace internal { | 
|  |  | 
|  | // The following three macros are used to share code and reduce | 
|  | // template junk across the various GEMM variants. | 
|  | #define CERES_GEMM_BEGIN(name)                                          \ | 
|  | template<int kRowA, int kColA, int kRowB, int kColB, int kOperation>  \ | 
|  | inline void name(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) | 
|  |  | 
|  | #define CERES_GEMM_NAIVE_HEADER                                         \ | 
|  | 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); | 
|  |  | 
|  | #define CERES_GEMM_EIGEN_HEADER                                         \ | 
|  | 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);                        \ | 
|  |  | 
|  | #define CERES_CALL_GEMM(name)                                           \ | 
|  | name<kRowA, kColA, kRowB, kColB, kOperation>(                         \ | 
|  | A, num_row_a, num_col_a,                                          \ | 
|  | B, num_row_b, num_col_b,                                          \ | 
|  | C, start_row_c, start_col_c, row_stride_c, col_stride_c); | 
|  |  | 
|  |  | 
|  | // For the matrix-matrix functions below, there are three variants for | 
|  | // each functionality. Foo, FooNaive and FooEigen. Foo is the one to | 
|  | // be called by the user. FooNaive is a basic loop based | 
|  | // implementation and FooEigen uses Eigen's implementation. Foo | 
|  | // chooses between FooNaive and FooEigen depending on how many of the | 
|  | // template arguments are fixed at compile time. Currently, FooEigen | 
|  | // is called if all matrix dimensions are compile time | 
|  | // constants. FooNaive is called otherwise. This leads to the best | 
|  | // performance currently. | 
|  | // | 
|  | // The MatrixMatrixMultiply variants compute: | 
|  | // | 
|  | //   C op A * B; | 
|  | // | 
|  | // The MatrixTransposeMatrixMultiply variants compute: | 
|  | // | 
|  | //   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 functions 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--- | 
|  | //   ------------ | 
|  | //   ------------ | 
|  | //   ------------ | 
|  | // | 
|  | CERES_GEMM_BEGIN(MatrixMatrixMultiplyEigen) { | 
|  | CERES_GEMM_EIGEN_HEADER | 
|  | Eigen::Block<MatrixRef, kRowA, kColB> | 
|  | block(Cref, start_row_c, start_col_c, num_row_a, num_col_b); | 
|  |  | 
|  | if (kOperation > 0) { | 
|  | block.noalias() += Aref * Bref; | 
|  | } else if (kOperation < 0) { | 
|  | block.noalias() -= Aref * Bref; | 
|  | } else { | 
|  | block.noalias() = Aref * Bref; | 
|  | } | 
|  | } | 
|  |  | 
|  | CERES_GEMM_BEGIN(MatrixMatrixMultiplyNaive) { | 
|  | CERES_GEMM_NAIVE_HEADER | 
|  | 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_LE(start_row_c + NUM_ROW_C, row_stride_c); | 
|  | DCHECK_LE(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; | 
|  | } | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | CERES_GEMM_BEGIN(MatrixMatrixMultiply) { | 
|  | #ifdef CERES_NO_CUSTOM_BLAS | 
|  |  | 
|  | CERES_CALL_GEMM(MatrixMatrixMultiplyEigen) | 
|  | return; | 
|  |  | 
|  | #else | 
|  |  | 
|  | if (kRowA != Eigen::Dynamic && kColA != Eigen::Dynamic && | 
|  | kRowB != Eigen::Dynamic && kColB != Eigen::Dynamic) { | 
|  | CERES_CALL_GEMM(MatrixMatrixMultiplyEigen) | 
|  | } else { | 
|  | CERES_CALL_GEMM(MatrixMatrixMultiplyNaive) | 
|  | } | 
|  |  | 
|  | #endif | 
|  | } | 
|  |  | 
|  | CERES_GEMM_BEGIN(MatrixTransposeMatrixMultiplyEigen) { | 
|  | CERES_GEMM_EIGEN_HEADER | 
|  | Eigen::Block<MatrixRef, kColA, kColB> block(Cref, | 
|  | start_row_c, start_col_c, | 
|  | num_col_a, num_col_b); | 
|  | if (kOperation > 0) { | 
|  | block.noalias() += Aref.transpose() * Bref; | 
|  | } else if (kOperation < 0) { | 
|  | block.noalias() -= Aref.transpose() * Bref; | 
|  | } else { | 
|  | block.noalias() = Aref.transpose() * Bref; | 
|  | } | 
|  | } | 
|  |  | 
|  | CERES_GEMM_BEGIN(MatrixTransposeMatrixMultiplyNaive) { | 
|  | CERES_GEMM_NAIVE_HEADER | 
|  | 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_LE(start_row_c + NUM_ROW_C, row_stride_c); | 
|  | DCHECK_LE(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; | 
|  | } | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | CERES_GEMM_BEGIN(MatrixTransposeMatrixMultiply) { | 
|  | #ifdef CERES_NO_CUSTOM_BLAS | 
|  |  | 
|  | CERES_CALL_GEMM(MatrixTransposeMatrixMultiplyEigen) | 
|  | return; | 
|  |  | 
|  | #else | 
|  |  | 
|  | if (kRowA != Eigen::Dynamic && kColA != Eigen::Dynamic && | 
|  | kRowB != Eigen::Dynamic && kColB != Eigen::Dynamic) { | 
|  | CERES_CALL_GEMM(MatrixTransposeMatrixMultiplyEigen) | 
|  | } else { | 
|  | CERES_CALL_GEMM(MatrixTransposeMatrixMultiplyNaive) | 
|  | } | 
|  |  | 
|  | #endif | 
|  | } | 
|  |  | 
|  | // Matrix-Vector multiplication | 
|  | // | 
|  | // 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 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); | 
|  |  | 
|  | // lazyProduct works better than .noalias() for matrix-vector | 
|  | // products. | 
|  | if (kOperation > 0) { | 
|  | cref += Aref.lazyProduct(bref); | 
|  | } else if (kOperation < 0) { | 
|  | cref -= Aref.lazyProduct(bref); | 
|  | } else { | 
|  | cref = Aref.lazyProduct(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 | 
|  | } | 
|  |  | 
|  | // Similar to MatrixVectorMultiply, except that A is transposed, i.e., | 
|  | // | 
|  | // c op 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); | 
|  |  | 
|  | // lazyProduct works better than .noalias() for matrix-vector | 
|  | // products. | 
|  | if (kOperation > 0) { | 
|  | cref += Aref.transpose().lazyProduct(bref); | 
|  | } else if (kOperation < 0) { | 
|  | cref -= Aref.transpose().lazyProduct(bref); | 
|  | } else { | 
|  | cref = Aref.transpose().lazyProduct(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_GEMM_BEGIN | 
|  | #undef CERES_GEMM_EIGEN_HEADER | 
|  | #undef CERES_GEMM_NAIVE_HEADER | 
|  | #undef CERES_CALL_GEMM | 
|  |  | 
|  | }  // namespace internal | 
|  | }  // namespace ceres | 
|  |  | 
|  | #endif  // CERES_INTERNAL_SMALL_BLAS_H_ |