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Posted to commits@mahout.apache.org by ap...@apache.org on 2016/06/10 16:52:35 UTC

[30/51] [partial] mahout git commit: Revert "(nojira) add native-viennaCL module to codebase. closes apache/mahout#241"

http://git-wip-us.apache.org/repos/asf/mahout/blob/7ae549fa/native-viennaCL/src/main/cpp/viennacl/linalg/cuda/sparse_matrix_operations_solve.hpp
----------------------------------------------------------------------
diff --git a/native-viennaCL/src/main/cpp/viennacl/linalg/cuda/sparse_matrix_operations_solve.hpp b/native-viennaCL/src/main/cpp/viennacl/linalg/cuda/sparse_matrix_operations_solve.hpp
deleted file mode 100644
index 24bcf96..0000000
--- a/native-viennaCL/src/main/cpp/viennacl/linalg/cuda/sparse_matrix_operations_solve.hpp
+++ /dev/null
@@ -1,761 +0,0 @@
-#ifndef VIENNACL_LINALG_CUDA_SPARSE_MATRIX_OPERATIONS_SOLVE_HPP_
-#define VIENNACL_LINALG_CUDA_SPARSE_MATRIX_OPERATIONS_SOLVE_HPP_
-
-/* =========================================================================
-   Copyright (c) 2010-2016, Institute for Microelectronics,
-                            Institute for Analysis and Scientific Computing,
-                            TU Wien.
-   Portions of this software are copyright by UChicago Argonne, LLC.
-
-                            -----------------
-                  ViennaCL - The Vienna Computing Library
-                            -----------------
-
-   Project Head:    Karl Rupp                   rupp@iue.tuwien.ac.at
-
-   (A list of authors and contributors can be found in the manual)
-
-   License:         MIT (X11), see file LICENSE in the base directory
-============================================================================= */
-
-/** @file viennacl/linalg/cuda/sparse_matrix_operations_solve.hpp
-    @brief Implementations of direct triangular solvers for sparse matrices using CUDA
-*/
-
-#include "viennacl/forwards.h"
-
-namespace viennacl
-{
-namespace linalg
-{
-namespace cuda
-{
-//
-// Compressed matrix
-//
-
-//
-// non-transposed
-//
-
-template<typename NumericT>
-__global__ void csr_unit_lu_forward_kernel(
-          const unsigned int * row_indices,
-          const unsigned int * column_indices,
-          const NumericT * elements,
-                NumericT * vector,
-          unsigned int size)
-{
-  __shared__  unsigned int col_index_buffer[128];
-  __shared__  NumericT element_buffer[128];
-  __shared__  NumericT vector_buffer[128];
-
-  unsigned int nnz = row_indices[size];
-  unsigned int current_row = 0;
-  unsigned int row_at_window_start = 0;
-  NumericT current_vector_entry = vector[0];
-  unsigned int loop_end = (nnz / blockDim.x + 1) * blockDim.x;
-  unsigned int next_row = row_indices[1];
-
-  for (unsigned int i = threadIdx.x; i < loop_end; i += blockDim.x)
-  {
-    //load into shared memory (coalesced access):
-    if (i < nnz)
-    {
-      element_buffer[threadIdx.x] = elements[i];
-      unsigned int tmp = column_indices[i];
-      col_index_buffer[threadIdx.x] = tmp;
-      vector_buffer[threadIdx.x] = vector[tmp];
-    }
-
-    __syncthreads();
-
-    //now a single thread does the remaining work in shared memory:
-    if (threadIdx.x == 0)
-    {
-      // traverse through all the loaded data:
-      for (unsigned int k=0; k<blockDim.x; ++k)
-      {
-        if (current_row < size && i+k == next_row) //current row is finished. Write back result
-        {
-          vector[current_row] = current_vector_entry;
-          ++current_row;
-          if (current_row < size) //load next row's data
-          {
-            next_row = row_indices[current_row+1];
-            current_vector_entry = vector[current_row];
-          }
-        }
-
-        if (current_row < size && col_index_buffer[k] < current_row) //substitute
-        {
-          if (col_index_buffer[k] < row_at_window_start) //use recently computed results
-            current_vector_entry -= element_buffer[k] * vector_buffer[k];
-          else if (col_index_buffer[k] < current_row) //use buffered data
-            current_vector_entry -= element_buffer[k] * vector[col_index_buffer[k]];
-        }
-
-      } // for k
-
-      row_at_window_start = current_row;
-    } // if (get_local_id(0) == 0)
-
-    __syncthreads();
-  } //for i
-}
-
-
-
-template<typename NumericT>
-__global__ void csr_lu_forward_kernel(
-          const unsigned int * row_indices,
-          const unsigned int * column_indices,
-          const NumericT * elements,
-                NumericT * vector,
-          unsigned int size)
-{
-  __shared__  unsigned int col_index_buffer[128];
-  __shared__  NumericT element_buffer[128];
-  __shared__  NumericT vector_buffer[128];
-
-  unsigned int nnz = row_indices[size];
-  unsigned int current_row = 0;
-  unsigned int row_at_window_start = 0;
-  NumericT current_vector_entry = vector[0];
-  NumericT diagonal_entry = 0;
-  unsigned int loop_end = (nnz / blockDim.x + 1) * blockDim.x;
-  unsigned int next_row = row_indices[1];
-
-  for (unsigned int i = threadIdx.x; i < loop_end; i += blockDim.x)
-  {
-    //load into shared memory (coalesced access):
-    if (i < nnz)
-    {
-      element_buffer[threadIdx.x] = elements[i];
-      unsigned int tmp = column_indices[i];
-      col_index_buffer[threadIdx.x] = tmp;
-      vector_buffer[threadIdx.x] = vector[tmp];
-    }
-
-    __syncthreads();
-
-    //now a single thread does the remaining work in shared memory:
-    if (threadIdx.x == 0)
-    {
-      // traverse through all the loaded data:
-      for (unsigned int k=0; k<blockDim.x; ++k)
-      {
-        if (current_row < size && i+k == next_row) //current row is finished. Write back result
-        {
-          vector[current_row] = current_vector_entry / diagonal_entry;
-          ++current_row;
-          if (current_row < size) //load next row's data
-          {
-            next_row = row_indices[current_row+1];
-            current_vector_entry = vector[current_row];
-          }
-        }
-
-        if (current_row < size && col_index_buffer[k] < current_row) //substitute
-        {
-          if (col_index_buffer[k] < row_at_window_start) //use recently computed results
-            current_vector_entry -= element_buffer[k] * vector_buffer[k];
-          else if (col_index_buffer[k] < current_row) //use buffered data
-            current_vector_entry -= element_buffer[k] * vector[col_index_buffer[k]];
-        }
-        else if (col_index_buffer[k] == current_row)
-          diagonal_entry = element_buffer[k];
-
-      } // for k
-
-      row_at_window_start = current_row;
-    } // if (get_local_id(0) == 0)
-
-    __syncthreads();
-  } //for i
-}
-
-
-template<typename NumericT>
-__global__ void csr_unit_lu_backward_kernel(
-          const unsigned int * row_indices,
-          const unsigned int * column_indices,
-          const NumericT * elements,
-                NumericT * vector,
-          unsigned int size)
-{
-  __shared__  unsigned int col_index_buffer[128];
-  __shared__  NumericT element_buffer[128];
-  __shared__  NumericT vector_buffer[128];
-
-  unsigned int nnz = row_indices[size];
-  unsigned int current_row = size-1;
-  unsigned int row_at_window_start = size-1;
-  NumericT current_vector_entry = vector[size-1];
-  unsigned int loop_end = ( (nnz - 1) / blockDim.x) * blockDim.x;
-  unsigned int next_row = row_indices[size-1];
-
-  unsigned int i = loop_end + threadIdx.x;
-  while (1)
-  {
-    //load into shared memory (coalesced access):
-    if (i < nnz)
-    {
-      element_buffer[threadIdx.x] = elements[i];
-      unsigned int tmp = column_indices[i];
-      col_index_buffer[threadIdx.x] = tmp;
-      vector_buffer[threadIdx.x] = vector[tmp];
-    }
-
-    __syncthreads();
-
-    //now a single thread does the remaining work in shared memory:
-    if (threadIdx.x == 0)
-    {
-      // traverse through all the loaded data from back to front:
-      for (unsigned int k2=0; k2<blockDim.x; ++k2)
-      {
-        unsigned int k = (blockDim.x - k2) - 1;
-
-        if (i+k >= nnz)
-          continue;
-
-        if (col_index_buffer[k] > row_at_window_start) //use recently computed results
-          current_vector_entry -= element_buffer[k] * vector_buffer[k];
-        else if (col_index_buffer[k] > current_row) //use buffered data
-          current_vector_entry -= element_buffer[k] * vector[col_index_buffer[k]];
-
-        if (i+k == next_row) //current row is finished. Write back result
-        {
-          vector[current_row] = current_vector_entry;
-          if (current_row > 0) //load next row's data
-          {
-            --current_row;
-            next_row = row_indices[current_row];
-            current_vector_entry = vector[current_row];
-          }
-        }
-
-
-      } // for k
-
-      row_at_window_start = current_row;
-    } // if (get_local_id(0) == 0)
-
-    __syncthreads();
-
-    if (i < blockDim.x)
-      break;
-
-    i -= blockDim.x;
-  } //for i
-}
-
-
-
-template<typename NumericT>
-__global__ void csr_lu_backward_kernel(
-          const unsigned int * row_indices,
-          const unsigned int * column_indices,
-          const NumericT * elements,
-                NumericT * vector,
-          unsigned int size)
-{
-  __shared__  unsigned int col_index_buffer[128];
-  __shared__  NumericT element_buffer[128];
-  __shared__  NumericT vector_buffer[128];
-
-  unsigned int nnz = row_indices[size];
-  unsigned int current_row = size-1;
-  unsigned int row_at_window_start = size-1;
-  NumericT current_vector_entry = vector[size-1];
-  NumericT diagonal_entry;
-  unsigned int loop_end = ( (nnz - 1) / blockDim.x) * blockDim.x;
-  unsigned int next_row = row_indices[size-1];
-
-  unsigned int i = loop_end + threadIdx.x;
-  while (1)
-  {
-    //load into shared memory (coalesced access):
-    if (i < nnz)
-    {
-      element_buffer[threadIdx.x] = elements[i];
-      unsigned int tmp = column_indices[i];
-      col_index_buffer[threadIdx.x] = tmp;
-      vector_buffer[threadIdx.x] = vector[tmp];
-    }
-
-    __syncthreads();
-
-    //now a single thread does the remaining work in shared memory:
-    if (threadIdx.x == 0)
-    {
-      // traverse through all the loaded data from back to front:
-      for (unsigned int k2=0; k2<blockDim.x; ++k2)
-      {
-        unsigned int k = (blockDim.x - k2) - 1;
-
-        if (i+k >= nnz)
-          continue;
-
-        if (col_index_buffer[k] > row_at_window_start) //use recently computed results
-          current_vector_entry -= element_buffer[k] * vector_buffer[k];
-        else if (col_index_buffer[k] > current_row) //use buffered data
-          current_vector_entry -= element_buffer[k] * vector[col_index_buffer[k]];
-        else if (col_index_buffer[k] == current_row)
-          diagonal_entry = element_buffer[k];
-
-        if (i+k == next_row) //current row is finished. Write back result
-        {
-          vector[current_row] = current_vector_entry / diagonal_entry;
-          if (current_row > 0) //load next row's data
-          {
-            --current_row;
-            next_row = row_indices[current_row];
-            current_vector_entry = vector[current_row];
-          }
-        }
-
-
-      } // for k
-
-      row_at_window_start = current_row;
-    } // if (get_local_id(0) == 0)
-
-    __syncthreads();
-
-    if (i < blockDim.x)
-      break;
-
-    i -= blockDim.x;
-  } //for i
-}
-
-
-
-//
-// transposed
-//
-
-
-template<typename NumericT>
-__global__ void csr_trans_lu_forward_kernel2(
-          const unsigned int * row_indices,
-          const unsigned int * column_indices,
-          const NumericT * elements,
-                NumericT * vector,
-          unsigned int size)
-{
-  for (unsigned int row = 0; row < size; ++row)
-  {
-    NumericT result_entry = vector[row];
-
-    unsigned int row_start = row_indices[row];
-    unsigned int row_stop  = row_indices[row + 1];
-    for (unsigned int entry_index = row_start + threadIdx.x; entry_index < row_stop; entry_index += blockDim.x)
-    {
-      unsigned int col_index = column_indices[entry_index];
-      if (col_index > row)
-        vector[col_index] -= result_entry * elements[entry_index];
-    }
-
-    __syncthreads();
-  }
-}
-
-template<typename NumericT>
-__global__ void csr_trans_unit_lu_forward_kernel(
-          const unsigned int * row_indices,
-          const unsigned int * column_indices,
-          const NumericT * elements,
-                NumericT * vector,
-          unsigned int size)
-{
-  __shared__  unsigned int row_index_lookahead[256];
-  __shared__  unsigned int row_index_buffer[256];
-
-  unsigned int row_index;
-  unsigned int col_index;
-  NumericT matrix_entry;
-  unsigned int nnz = row_indices[size];
-  unsigned int row_at_window_start = 0;
-  unsigned int row_at_window_end = 0;
-  unsigned int loop_end = ( (nnz - 1) / blockDim.x + 1) * blockDim.x;
-
-  for (unsigned int i = threadIdx.x; i < loop_end; i += blockDim.x)
-  {
-    col_index    = (i < nnz) ? column_indices[i] : 0;
-    matrix_entry = (i < nnz) ? elements[i]       : 0;
-    row_index_lookahead[threadIdx.x] = (row_at_window_start + threadIdx.x < size) ? row_indices[row_at_window_start + threadIdx.x] : nnz;
-
-    __syncthreads();
-
-    if (i < nnz)
-    {
-      unsigned int row_index_inc = 0;
-      while (i >= row_index_lookahead[row_index_inc + 1])
-        ++row_index_inc;
-      row_index = row_at_window_start + row_index_inc;
-      row_index_buffer[threadIdx.x] = row_index;
-    }
-    else
-    {
-      row_index = size+1;
-      row_index_buffer[threadIdx.x] = size - 1;
-    }
-
-    __syncthreads();
-
-    row_at_window_start = row_index_buffer[0];
-    row_at_window_end   = row_index_buffer[blockDim.x - 1];
-
-    //forward elimination
-    for (unsigned int row = row_at_window_start; row <= row_at_window_end; ++row)
-    {
-      NumericT result_entry = vector[row];
-
-      if ( (row_index == row) && (col_index > row) )
-        vector[col_index] -= result_entry * matrix_entry;
-
-      __syncthreads();
-    }
-
-    row_at_window_start = row_at_window_end;
-  }
-
-}
-
-template<typename NumericT>
-__global__ void csr_trans_lu_forward_kernel(
-          const unsigned int * row_indices,
-          const unsigned int * column_indices,
-          const NumericT * elements,
-          const NumericT * diagonal_entries,
-                NumericT * vector,
-          unsigned int size)
-{
-  __shared__  unsigned int row_index_lookahead[256];
-  __shared__  unsigned int row_index_buffer[256];
-
-  unsigned int row_index;
-  unsigned int col_index;
-  NumericT matrix_entry;
-  unsigned int nnz = row_indices[size];
-  unsigned int row_at_window_start = 0;
-  unsigned int row_at_window_end = 0;
-  unsigned int loop_end = ( (nnz - 1) / blockDim.x + 1) * blockDim.x;
-
-  for (unsigned int i = threadIdx.x; i < loop_end; i += blockDim.x)
-  {
-    col_index    = (i < nnz) ? column_indices[i] : 0;
-    matrix_entry = (i < nnz) ? elements[i]       : 0;
-    row_index_lookahead[threadIdx.x] = (row_at_window_start + threadIdx.x < size) ? row_indices[row_at_window_start + threadIdx.x] : nnz;
-
-    __syncthreads();
-
-    if (i < nnz)
-    {
-      unsigned int row_index_inc = 0;
-      while (i >= row_index_lookahead[row_index_inc + 1])
-        ++row_index_inc;
-      row_index = row_at_window_start + row_index_inc;
-      row_index_buffer[threadIdx.x] = row_index;
-    }
-    else
-    {
-      row_index = size+1;
-      row_index_buffer[threadIdx.x] = size - 1;
-    }
-
-    __syncthreads();
-
-    row_at_window_start = row_index_buffer[0];
-    row_at_window_end   = row_index_buffer[blockDim.x - 1];
-
-    //forward elimination
-    for (unsigned int row = row_at_window_start; row <= row_at_window_end; ++row)
-    {
-      NumericT result_entry = vector[row] / diagonal_entries[row];
-
-      if ( (row_index == row) && (col_index > row) )
-        vector[col_index] -= result_entry * matrix_entry;
-
-      __syncthreads();
-    }
-
-    row_at_window_start = row_at_window_end;
-  }
-
-  // final step: Divide vector by diagonal entries:
-  for (unsigned int i = threadIdx.x; i < size; i += blockDim.x)
-    vector[i] /= diagonal_entries[i];
-
-}
-
-
-template<typename NumericT>
-__global__ void csr_trans_unit_lu_backward_kernel(
-          const unsigned int * row_indices,
-          const unsigned int * column_indices,
-          const NumericT * elements,
-                NumericT * vector,
-          unsigned int size)
-{
-  __shared__  unsigned int row_index_lookahead[256];
-  __shared__  unsigned int row_index_buffer[256];
-
-  unsigned int row_index;
-  unsigned int col_index;
-  NumericT matrix_entry;
-  unsigned int nnz = row_indices[size];
-  unsigned int row_at_window_start = size;
-  unsigned int row_at_window_end;
-  unsigned int loop_end = ( (nnz - 1) / blockDim.x + 1) * blockDim.x;
-
-  for (unsigned int i2 = threadIdx.x; i2 < loop_end; i2 += blockDim.x)
-  {
-    unsigned int i = (nnz - i2) - 1;
-    col_index    = (i2 < nnz) ? column_indices[i] : 0;
-    matrix_entry = (i2 < nnz) ? elements[i]       : 0;
-    row_index_lookahead[threadIdx.x] = (row_at_window_start >= threadIdx.x) ? row_indices[row_at_window_start - threadIdx.x] : 0;
-
-    __syncthreads();
-
-    if (i2 < nnz)
-    {
-      unsigned int row_index_dec = 0;
-      while (row_index_lookahead[row_index_dec] > i)
-        ++row_index_dec;
-      row_index = row_at_window_start - row_index_dec;
-      row_index_buffer[threadIdx.x] = row_index;
-    }
-    else
-    {
-      row_index = size+1;
-      row_index_buffer[threadIdx.x] = 0;
-    }
-
-    __syncthreads();
-
-    row_at_window_start = row_index_buffer[0];
-    row_at_window_end   = row_index_buffer[blockDim.x - 1];
-
-    //backward elimination
-    for (unsigned int row2 = 0; row2 <= (row_at_window_start - row_at_window_end); ++row2)
-    {
-      unsigned int row = row_at_window_start - row2;
-      NumericT result_entry = vector[row];
-
-      if ( (row_index == row) && (col_index < row) )
-        vector[col_index] -= result_entry * matrix_entry;
-
-      __syncthreads();
-    }
-
-    row_at_window_start = row_at_window_end;
-  }
-
-}
-
-
-
-template<typename NumericT>
-__global__ void csr_trans_lu_backward_kernel2(
-          const unsigned int * row_indices,
-          const unsigned int * column_indices,
-          const NumericT * elements,
-          const NumericT * diagonal_entries,
-                NumericT * vector,
-          unsigned int size)
-{
-  NumericT result_entry = 0;
-
-  //backward elimination, using U and D:
-  for (unsigned int row2 = 0; row2 < size; ++row2)
-  {
-    unsigned int row = (size - row2) - 1;
-    result_entry = vector[row] / diagonal_entries[row];
-
-    unsigned int row_start = row_indices[row];
-    unsigned int row_stop  = row_indices[row + 1];
-    for (unsigned int entry_index = row_start + threadIdx.x; entry_index < row_stop; ++entry_index)
-    {
-      unsigned int col_index = column_indices[entry_index];
-      if (col_index < row)
-        vector[col_index] -= result_entry * elements[entry_index];
-    }
-
-    __syncthreads();
-
-    if (threadIdx.x == 0)
-      vector[row] = result_entry;
-  }
-}
-
-
-template<typename NumericT>
-__global__ void csr_trans_lu_backward_kernel(
-          const unsigned int * row_indices,
-          const unsigned int * column_indices,
-          const NumericT * elements,
-          const NumericT * diagonal_entries,
-                NumericT * vector,
-          unsigned int size)
-{
-  __shared__  unsigned int row_index_lookahead[256];
-  __shared__  unsigned int row_index_buffer[256];
-
-  unsigned int row_index;
-  unsigned int col_index;
-  NumericT matrix_entry;
-  unsigned int nnz = row_indices[size];
-  unsigned int row_at_window_start = size;
-  unsigned int row_at_window_end;
-  unsigned int loop_end = ( (nnz - 1) / blockDim.x + 1) * blockDim.x;
-
-  for (unsigned int i2 = threadIdx.x; i2 < loop_end; i2 += blockDim.x)
-  {
-    unsigned int i = (nnz - i2) - 1;
-    col_index    = (i2 < nnz) ? column_indices[i] : 0;
-    matrix_entry = (i2 < nnz) ? elements[i]       : 0;
-    row_index_lookahead[threadIdx.x] = (row_at_window_start >= threadIdx.x) ? row_indices[row_at_window_start - threadIdx.x] : 0;
-
-    __syncthreads();
-
-    if (i2 < nnz)
-    {
-      unsigned int row_index_dec = 0;
-      while (row_index_lookahead[row_index_dec] > i)
-        ++row_index_dec;
-      row_index = row_at_window_start - row_index_dec;
-      row_index_buffer[threadIdx.x] = row_index;
-    }
-    else
-    {
-      row_index = size+1;
-      row_index_buffer[threadIdx.x] = 0;
-    }
-
-    __syncthreads();
-
-    row_at_window_start = row_index_buffer[0];
-    row_at_window_end   = row_index_buffer[blockDim.x - 1];
-
-    //backward elimination
-    for (unsigned int row2 = 0; row2 <= (row_at_window_start - row_at_window_end); ++row2)
-    {
-      unsigned int row = row_at_window_start - row2;
-      NumericT result_entry = vector[row] / diagonal_entries[row];
-
-      if ( (row_index == row) && (col_index < row) )
-        vector[col_index] -= result_entry * matrix_entry;
-
-      __syncthreads();
-    }
-
-    row_at_window_start = row_at_window_end;
-  }
-
-
-  // final step: Divide vector by diagonal entries:
-  for (unsigned int i = threadIdx.x; i < size; i += blockDim.x)
-    vector[i] /= diagonal_entries[i];
-
-}
-
-
-template<typename NumericT>
-__global__ void csr_block_trans_unit_lu_forward(
-          const unsigned int * row_jumper_L,      //L part (note that L is transposed in memory)
-          const unsigned int * column_indices_L,
-          const NumericT * elements_L,
-          const unsigned int * block_offsets,
-          NumericT * result,
-          unsigned int size)
-{
-  unsigned int col_start = block_offsets[2*blockIdx.x];
-  unsigned int col_stop  = block_offsets[2*blockIdx.x+1];
-  unsigned int row_start = row_jumper_L[col_start];
-  unsigned int row_stop;
-  NumericT result_entry = 0;
-
-  if (col_start >= col_stop)
-    return;
-
-  //forward elimination, using L:
-  for (unsigned int col = col_start; col < col_stop; ++col)
-  {
-    result_entry = result[col];
-    row_stop = row_jumper_L[col + 1];
-    for (unsigned int buffer_index = row_start + threadIdx.x; buffer_index < row_stop; buffer_index += blockDim.x)
-      result[column_indices_L[buffer_index]] -= result_entry * elements_L[buffer_index];
-    row_start = row_stop; //for next iteration (avoid unnecessary loads from GPU RAM)
-    __syncthreads();
-  }
-
-}
-
-
-template<typename NumericT>
-__global__ void csr_block_trans_lu_backward(
-          const unsigned int * row_jumper_U,      //U part (note that U is transposed in memory)
-          const unsigned int * column_indices_U,
-          const NumericT * elements_U,
-          const NumericT * diagonal_U,
-          const unsigned int * block_offsets,
-          NumericT * result,
-          unsigned int size)
-{
-  unsigned int col_start = block_offsets[2*blockIdx.x];
-  unsigned int col_stop  = block_offsets[2*blockIdx.x+1];
-  unsigned int row_start;
-  unsigned int row_stop;
-  NumericT result_entry = 0;
-
-  if (col_start >= col_stop)
-    return;
-
-  //backward elimination, using U and diagonal_U
-  for (unsigned int iter = 0; iter < col_stop - col_start; ++iter)
-  {
-    unsigned int col = (col_stop - iter) - 1;
-    result_entry = result[col] / diagonal_U[col];
-    row_start = row_jumper_U[col];
-    row_stop  = row_jumper_U[col + 1];
-    for (unsigned int buffer_index = row_start + threadIdx.x; buffer_index < row_stop; buffer_index += blockDim.x)
-      result[column_indices_U[buffer_index]] -= result_entry * elements_U[buffer_index];
-    __syncthreads();
-  }
-
-  //divide result vector by diagonal:
-  for (unsigned int col = col_start + threadIdx.x; col < col_stop; col += blockDim.x)
-    result[col] /= diagonal_U[col];
-}
-
-
-
-//
-// Coordinate Matrix
-//
-
-
-
-
-//
-// ELL Matrix
-//
-
-
-
-//
-// Hybrid Matrix
-//
-
-
-
-} // namespace opencl
-} //namespace linalg
-} //namespace viennacl
-
-
-#endif

http://git-wip-us.apache.org/repos/asf/mahout/blob/7ae549fa/native-viennaCL/src/main/cpp/viennacl/linalg/cuda/spgemm.hpp
----------------------------------------------------------------------
diff --git a/native-viennaCL/src/main/cpp/viennacl/linalg/cuda/spgemm.hpp b/native-viennaCL/src/main/cpp/viennacl/linalg/cuda/spgemm.hpp
deleted file mode 100644
index 5551cda..0000000
--- a/native-viennaCL/src/main/cpp/viennacl/linalg/cuda/spgemm.hpp
+++ /dev/null
@@ -1,793 +0,0 @@
-#ifndef VIENNACL_LINALG_CUDA_SPGEMM_HPP_
-#define VIENNACL_LINALG_CUDA_SPGEMM_HPP_
-
-/* =========================================================================
-   Copyright (c) 2010-2016, Institute for Microelectronics,
-                            Institute for Analysis and Scientific Computing,
-                            TU Wien.
-   Portions of this software are copyright by UChicago Argonne, LLC.
-
-                            -----------------
-                  ViennaCL - The Vienna Computing Library
-                            -----------------
-
-   Project Head:    Karl Rupp                   rupp@iue.tuwien.ac.at
-
-   (A list of authors and contributors can be found in the manual)
-
-   License:         MIT (X11), see file LICENSE in the base directory
-============================================================================= */
-
-/** @file viennacl/linalg/cuda/sparse_matrix_operations.hpp
-    @brief Implementations of operations using sparse matrices using CUDA
-*/
-
-#include <stdexcept>
-
-#include <thrust/scan.h>
-#include <thrust/device_ptr.h>
-
-#include "viennacl/forwards.h"
-#include "viennacl/scalar.hpp"
-#include "viennacl/vector.hpp"
-#include "viennacl/tools/tools.hpp"
-#include "viennacl/linalg/cuda/common.hpp"
-
-#include "viennacl/tools/timer.hpp"
-
-#include "viennacl/linalg/cuda/sparse_matrix_operations_solve.hpp"
-
-namespace viennacl
-{
-namespace linalg
-{
-namespace cuda
-{
-
-/** @brief Loads a value from the specified address. With CUDA arch 3.5 and above the value is also stored in global constant memory for later reuse */
-template<typename NumericT>
-static inline __device__ NumericT load_and_cache(const NumericT *address)
-{
-#if defined(__CUDA_ARCH__) && __CUDA_ARCH__ >= 350
-  return __ldg(address);
-#else
-  return *address;
-#endif
-}
-
-
-//
-// Stage 1: Obtain upper bound for number of elements per row in C:
-//
-template<typename IndexT>
-__device__ IndexT round_to_next_power_of_2(IndexT val)
-{
-  if (val > 32)
-    return 64; // just to indicate that we need to split/factor the matrix!
-  else if (val > 16)
-    return 32;
-  else if (val > 8)
-    return 16;
-  else if (val > 4)
-    return 8;
-  else if (val > 2)
-    return 4;
-  else if (val > 1)
-    return 2;
-  else
-    return 1;
-}
-
-template<typename IndexT>
-__global__ void compressed_matrix_gemm_stage_1(
-          const IndexT * A_row_indices,
-          const IndexT * A_col_indices,
-          IndexT A_size1,
-          const IndexT * B_row_indices,
-          IndexT *subwarpsize_per_group,
-          IndexT *max_nnz_row_A_per_group,
-          IndexT *max_nnz_row_B_per_group)
-{
-  unsigned int subwarpsize_in_thread = 0;
-  unsigned int max_nnz_row_A = 0;
-  unsigned int max_nnz_row_B = 0;
-
-  unsigned int rows_per_group = (A_size1 - 1) / gridDim.x + 1;
-  unsigned int row_per_group_end = min(A_size1, rows_per_group * (blockIdx.x + 1));
-
-  for (unsigned int row = rows_per_group * blockIdx.x + threadIdx.x; row < row_per_group_end; row += blockDim.x)
-  {
-    unsigned int A_row_start = A_row_indices[row];
-    unsigned int A_row_end   = A_row_indices[row+1];
-    unsigned int row_num = A_row_end - A_row_start;
-    if (row_num > 32) // too many rows in B need to be merged for a single pass
-    {
-      unsigned int subwarp_sqrt = (unsigned int)sqrt(double(row_num)) + 1;
-      subwarpsize_in_thread = max(subwarp_sqrt, subwarpsize_in_thread);
-    }
-    else
-      subwarpsize_in_thread = max(A_row_end - A_row_start, subwarpsize_in_thread);
-    max_nnz_row_A = max(max_nnz_row_A, row_num);
-    for (unsigned int j = A_row_start; j < A_row_end; ++j)
-    {
-      unsigned int col = A_col_indices[j];
-      unsigned int row_len_B = B_row_indices[col + 1] - B_row_indices[col];
-      max_nnz_row_B = max(row_len_B, max_nnz_row_B);
-    }
-  }
-
-  // reduction to obtain maximum in thread block
-  __shared__ unsigned int shared_subwarpsize[256];
-  __shared__ unsigned int shared_max_nnz_row_A[256];
-  __shared__ unsigned int shared_max_nnz_row_B[256];
-
-    shared_subwarpsize[threadIdx.x] = subwarpsize_in_thread;
-  shared_max_nnz_row_A[threadIdx.x] = max_nnz_row_A;
-  shared_max_nnz_row_B[threadIdx.x] = max_nnz_row_B;
-  for (unsigned int stride = blockDim.x/2; stride > 0; stride /= 2)
-  {
-    __syncthreads();
-    if (threadIdx.x < stride)
-    {
-        shared_subwarpsize[threadIdx.x] = max(  shared_subwarpsize[threadIdx.x],   shared_subwarpsize[threadIdx.x + stride]);
-      shared_max_nnz_row_A[threadIdx.x] = max(shared_max_nnz_row_A[threadIdx.x], shared_max_nnz_row_A[threadIdx.x + stride]);
-      shared_max_nnz_row_B[threadIdx.x] = max(shared_max_nnz_row_B[threadIdx.x], shared_max_nnz_row_B[threadIdx.x + stride]);
-    }
-  }
-
-  if (threadIdx.x == 0)
-  {
-      subwarpsize_per_group[blockIdx.x] = round_to_next_power_of_2(shared_subwarpsize[0]);
-    max_nnz_row_A_per_group[blockIdx.x] = shared_max_nnz_row_A[0];
-    max_nnz_row_B_per_group[blockIdx.x] = shared_max_nnz_row_B[0];
-  }
-}
-
-//
-// Stage 2: Determine sparsity pattern of C
-//
-inline __device__ unsigned int merge_subwarp_symbolic(unsigned int row_B_start, unsigned int row_B_end, unsigned int const *B_col_indices, unsigned int B_size2, unsigned int subwarpsize)
-{
-  unsigned int current_front_index = (row_B_start < row_B_end) ? load_and_cache(B_col_indices + row_B_start) : B_size2;
-
-  unsigned int num_nnz = 0;
-  while (1)
-  {
-    // determine current minimum (warp shuffle)
-    unsigned int min_index = current_front_index;
-    for (unsigned int i = subwarpsize/2; i >= 1; i /= 2)
-      min_index = min(min_index, __shfl_xor((int)min_index, (int)i));
-
-    if (min_index == B_size2)
-      break;
-
-    // update front:
-    current_front_index = (current_front_index == min_index) ? ((++row_B_start < row_B_end) ? load_and_cache(B_col_indices + row_B_start) : B_size2)
-                                                             : current_front_index;
-    ++num_nnz;
-  }
-
-  return num_nnz;
-}
-
-inline __device__ unsigned int merge_subwarp_symbolic_double(unsigned int row_B_start, unsigned int row_B_end, unsigned int const *B_col_indices, unsigned int B_size2,
-                                                             unsigned int *output_array, unsigned int id_in_warp, unsigned int subwarpsize)
-{
-  unsigned int current_front_index = (row_B_start < row_B_end) ? load_and_cache(B_col_indices + row_B_start) : B_size2;
-
-  unsigned int num_nnz = 0;
-  unsigned int index_buffer = 0;
-  unsigned int buffer_size = 0;
-  while (1)
-  {
-    // determine current minimum (warp shuffle)
-    unsigned int min_index = current_front_index;
-    for (unsigned int i = subwarpsize/2; i >= 1; i /= 2)
-      min_index = min(min_index, __shfl_xor((int)min_index, (int)i));
-
-    if (min_index == B_size2)
-      break;
-
-    // update front:
-    current_front_index = (current_front_index == min_index) ? ((++row_B_start < row_B_end) ? load_and_cache(B_col_indices + row_B_start) : B_size2)
-                                                             : current_front_index;
-
-    // write output
-    index_buffer = (id_in_warp == buffer_size) ? min_index : index_buffer;
-    ++buffer_size;
-
-    if (buffer_size == subwarpsize) // register buffer full?
-    {
-      output_array[id_in_warp] = index_buffer;
-      output_array += subwarpsize;
-      buffer_size = 0;
-    }
-
-    ++num_nnz;
-  }
-
-  // write remaining entries from register buffer:
-  if (id_in_warp < buffer_size)
-    output_array[id_in_warp] = index_buffer;
-
-  return num_nnz;
-}
-
-template<typename IndexT>
-__global__ void compressed_matrix_gemm_stage_2(
-          const IndexT * A_row_indices,
-          const IndexT * A_col_indices,
-          IndexT A_size1,
-          const IndexT * B_row_indices,
-          const IndexT * B_col_indices,
-          IndexT B_size2,
-          IndexT * C_row_indices,
-          unsigned int *subwarpsize_array,
-          unsigned int *max_row_size_A,
-          unsigned int *max_row_size_B,
-          unsigned int *scratchpad_offsets,
-          unsigned int *scratchpad_indices)
-{
-  unsigned int subwarpsize = subwarpsize_array[blockIdx.x];
-
-  unsigned int num_warps  =  blockDim.x / subwarpsize;
-  unsigned int warp_id    = threadIdx.x / subwarpsize;
-  unsigned int id_in_warp = threadIdx.x % subwarpsize;
-
-  unsigned int scratchpad_rowlength     = max_row_size_B[blockIdx.x] * subwarpsize;
-  unsigned int scratchpad_rows_per_warp = max_row_size_A[blockIdx.x] / subwarpsize + 1;
-  unsigned int *subwarp_scratchpad_start = scratchpad_indices + scratchpad_offsets[blockIdx.x] + warp_id * scratchpad_rows_per_warp * scratchpad_rowlength;
-
-  unsigned int rows_per_group = (A_size1 - 1) / gridDim.x + 1;
-  unsigned int row_per_group_end = min(A_size1, rows_per_group * (blockIdx.x + 1));
-
-  for (unsigned int row = rows_per_group * blockIdx.x + warp_id; row < row_per_group_end; row += num_warps)
-  {
-    unsigned int row_A_start = A_row_indices[row];
-    unsigned int row_A_end   = A_row_indices[row+1];
-
-    if (row_A_end - row_A_start > subwarpsize)
-    {
-      unsigned int final_merge_start = 0;
-      unsigned int final_merge_end   = 0;
-
-      // merge to temporary scratchpad memory:
-      unsigned int *subwarp_scratchpad = subwarp_scratchpad_start;
-      unsigned int iter = 0;
-      while (row_A_end > row_A_start)
-      {
-        unsigned int my_row_B = row_A_start + id_in_warp;
-        unsigned int row_B_index = (my_row_B < row_A_end) ? A_col_indices[my_row_B] : 0;
-        unsigned int row_B_start = (my_row_B < row_A_end) ? load_and_cache(B_row_indices + row_B_index) : 0;
-        unsigned int row_B_end   = (my_row_B < row_A_end) ? load_and_cache(B_row_indices + row_B_index + 1) : 0;
-
-        unsigned int nnz_in_merge = merge_subwarp_symbolic_double(row_B_start, row_B_end, B_col_indices, B_size2,
-                                                                  subwarp_scratchpad, id_in_warp, subwarpsize);
-
-        final_merge_start = (iter == id_in_warp) ? subwarp_scratchpad - scratchpad_indices : final_merge_start;
-        final_merge_end   = (iter == id_in_warp) ? final_merge_start + nnz_in_merge        : final_merge_end;
-        ++iter;
-
-        row_A_start += subwarpsize;
-        subwarp_scratchpad += scratchpad_rowlength; // write to next row in scratchpad
-      }
-
-      // final merge:
-      unsigned int num_nnz = merge_subwarp_symbolic(final_merge_start, final_merge_end, scratchpad_indices, B_size2, subwarpsize);
-
-      if (id_in_warp == 0)
-        C_row_indices[row] = num_nnz;
-    }
-    else
-    {
-      // single merge
-      unsigned int my_row_B = row_A_start + id_in_warp;
-      unsigned int row_B_index = (my_row_B < row_A_end) ? A_col_indices[my_row_B] : 0;
-      unsigned int row_B_start = (my_row_B < row_A_end) ? load_and_cache(B_row_indices + row_B_index) : 0;
-      unsigned int row_B_end   = (my_row_B < row_A_end) ? load_and_cache(B_row_indices + row_B_index + 1) : 0;
-
-      unsigned int num_nnz = merge_subwarp_symbolic(row_B_start, row_B_end, B_col_indices, B_size2, subwarpsize);
-
-      if (id_in_warp == 0)
-        C_row_indices[row] = num_nnz;
-    }
-  }
-
-}
-
-
-//
-// Stage 3: Fill C with values
-//
-template<typename NumericT>
-__device__ unsigned int merge_subwarp_numeric(NumericT scaling_factor,
-                                              unsigned int input_start, unsigned int input_end, const unsigned int *input_indices, const NumericT *input_values, unsigned int invalid_token,
-                                              unsigned int *output_indices, NumericT *output_values,
-                                              unsigned int id_in_warp, unsigned int subwarpsize)
-{
-  unsigned int current_front_index = (input_start < input_end) ? load_and_cache(input_indices + input_start) : invalid_token;
-  NumericT     current_front_value = (input_start < input_end) ? load_and_cache(input_values  + input_start) : 0;
-
-  unsigned int index_buffer = 0;
-  NumericT     value_buffer = 0;
-  unsigned int buffer_size = 0;
-  unsigned int nnz_written = 0;
-  while (1)
-  {
-    // determine current minimum:
-    unsigned int min_index = current_front_index;
-    for (unsigned int i = subwarpsize/2; i >= 1; i /= 2)
-      min_index = min(min_index, __shfl_xor((int)min_index, (int)i));
-
-    if (min_index == invalid_token) // done
-      break;
-
-    // compute entry in C:
-    NumericT output_value = (current_front_index == min_index) ? scaling_factor * current_front_value : 0;
-    for (unsigned int i = subwarpsize/2; i >= 1; i /= 2)
-      output_value += __shfl_xor((int)output_value, (int)i);
-
-    // update front:
-    if (current_front_index == min_index)
-    {
-      ++input_start;
-      current_front_index = (input_start < input_end) ? load_and_cache(input_indices + input_start) : invalid_token;
-      current_front_value = (input_start < input_end) ? load_and_cache(input_values  + input_start) : 0;
-    }
-
-    // write current front to register buffer:
-    index_buffer = (id_in_warp == buffer_size) ? min_index    : index_buffer;
-    value_buffer = (id_in_warp == buffer_size) ? output_value : value_buffer;
-    ++buffer_size;
-
-    // flush register buffer via a coalesced write once full:
-    if (buffer_size == subwarpsize)
-    {
-      output_indices[id_in_warp] = index_buffer; output_indices += subwarpsize;
-      output_values[id_in_warp]  = value_buffer; output_values  += subwarpsize;
-      buffer_size = 0;
-    }
-
-    ++nnz_written;
-  }
-
-  // write remaining entries in register buffer to C:
-  if (id_in_warp < buffer_size)
-  {
-    output_indices[id_in_warp] = index_buffer;
-    output_values[id_in_warp]  = value_buffer;
-  }
-
-  return nnz_written;
-}
-
-template<typename IndexT, typename NumericT>
-__global__ void compressed_matrix_gemm_stage_3(
-          const IndexT * A_row_indices,
-          const IndexT * A_col_indices,
-          const NumericT * A_elements,
-          IndexT A_size1,
-          const IndexT * B_row_indices,
-          const IndexT * B_col_indices,
-          const NumericT * B_elements,
-          IndexT B_size2,
-          IndexT const * C_row_indices,
-          IndexT * C_col_indices,
-          NumericT * C_elements,
-          unsigned int *subwarpsize_array,
-          unsigned int *max_row_size_A,
-          unsigned int *max_row_size_B,
-          unsigned int *scratchpad_offsets,
-          unsigned int *scratchpad_indices,
-          NumericT *scratchpad_values)
-{
-  unsigned int subwarpsize = subwarpsize_array[blockIdx.x];
-
-  unsigned int num_warps  =  blockDim.x / subwarpsize;
-  unsigned int warp_id    = threadIdx.x / subwarpsize;
-  unsigned int id_in_warp = threadIdx.x % subwarpsize;
-
-  unsigned int scratchpad_rowlength     = max_row_size_B[blockIdx.x] * subwarpsize;
-  unsigned int scratchpad_rows_per_warp = max_row_size_A[blockIdx.x] / subwarpsize + 1;
-  unsigned int subwarp_scratchpad_shift = scratchpad_offsets[blockIdx.x] + warp_id * scratchpad_rows_per_warp * scratchpad_rowlength;
-
-  unsigned int rows_per_group = (A_size1 - 1) / gridDim.x + 1;
-  unsigned int row_per_group_end = min(A_size1, rows_per_group * (blockIdx.x + 1));
-
-  for (unsigned int row = rows_per_group * blockIdx.x + warp_id; row < row_per_group_end; row += num_warps)
-  {
-    unsigned int row_A_start = A_row_indices[row];
-    unsigned int row_A_end   = A_row_indices[row+1];
-
-    if (row_A_end - row_A_start > subwarpsize)
-    {
-      // first merge stage:
-      unsigned int final_merge_start = 0;
-      unsigned int final_merge_end = 0;
-      unsigned int iter = 0;
-      unsigned int *scratchpad_indices_ptr = scratchpad_indices + subwarp_scratchpad_shift;
-      NumericT     *scratchpad_values_ptr  = scratchpad_values  + subwarp_scratchpad_shift;
-
-      while (row_A_start < row_A_end)
-      {
-        unsigned int my_row_B = row_A_start + id_in_warp;
-        unsigned int row_B_index = (my_row_B < row_A_end) ? A_col_indices[my_row_B] : 0;
-        unsigned int row_B_start = (my_row_B < row_A_end) ? load_and_cache(B_row_indices + row_B_index)     : 0;
-        unsigned int row_B_end   = (my_row_B < row_A_end) ? load_and_cache(B_row_indices + row_B_index + 1) : 0;
-        NumericT val_A = (my_row_B < row_A_end) ? A_elements[my_row_B] : 0;
-
-        unsigned int nnz_written = merge_subwarp_numeric(val_A,
-                                                         row_B_start, row_B_end, B_col_indices, B_elements, B_size2,
-                                                         scratchpad_indices_ptr, scratchpad_values_ptr,
-                                                         id_in_warp, subwarpsize);
-
-        if (iter == id_in_warp)
-        {
-          final_merge_start = scratchpad_indices_ptr - scratchpad_indices;
-          final_merge_end   = final_merge_start + nnz_written;
-        }
-        ++iter;
-
-        row_A_start += subwarpsize;
-        scratchpad_indices_ptr += scratchpad_rowlength;
-        scratchpad_values_ptr  += scratchpad_rowlength;
-      }
-
-      // second merge stage:
-      unsigned int index_in_C = C_row_indices[row];
-      merge_subwarp_numeric(NumericT(1),
-                            final_merge_start, final_merge_end, scratchpad_indices, scratchpad_values, B_size2,
-                            C_col_indices + index_in_C, C_elements + index_in_C,
-                            id_in_warp, subwarpsize);
-    }
-    else
-    {
-      unsigned int my_row_B = row_A_start + id_in_warp;
-      unsigned int row_B_index = (my_row_B < row_A_end) ? A_col_indices[my_row_B] : 0;
-      unsigned int row_B_start = (my_row_B < row_A_end) ? load_and_cache(B_row_indices + row_B_index)     : 0;
-      unsigned int row_B_end   = (my_row_B < row_A_end) ? load_and_cache(B_row_indices + row_B_index + 1) : 0;
-      NumericT val_A = (my_row_B < row_A_end) ? A_elements[my_row_B] : 0;
-
-      unsigned int index_in_C = C_row_indices[row];
-
-      merge_subwarp_numeric(val_A,
-                            row_B_start, row_B_end, B_col_indices, B_elements, B_size2,
-                            C_col_indices + index_in_C, C_elements + index_in_C,
-                            id_in_warp, subwarpsize);
-    }
-  }
-
-}
-
-
-
-
-//
-// Decomposition kernels:
-//
-template<typename IndexT>
-__global__ void compressed_matrix_gemm_decompose_1(
-          const IndexT * A_row_indices,
-          IndexT A_size1,
-          IndexT max_per_row,
-          IndexT *chunks_per_row)
-{
-  for (IndexT i = blockIdx.x * blockDim.x + threadIdx.x; i < A_size1; i += blockDim.x * gridDim.x)
-  {
-    IndexT num_entries = A_row_indices[i+1] - A_row_indices[i];
-    chunks_per_row[i] = (num_entries < max_per_row) ? 1 : ((num_entries - 1)/ max_per_row + 1);
-  }
-}
-
-
-template<typename IndexT, typename NumericT>
-__global__ void compressed_matrix_gemm_A2(
-          IndexT * A2_row_indices,
-          IndexT * A2_col_indices,
-          NumericT * A2_elements,
-          IndexT A2_size1,
-          IndexT *new_row_buffer)
-{
-  for (IndexT i = blockIdx.x * blockDim.x + threadIdx.x; i < A2_size1; i += blockDim.x * gridDim.x)
-  {
-    unsigned int index_start = new_row_buffer[i];
-    unsigned int index_stop  = new_row_buffer[i+1];
-
-    A2_row_indices[i] = index_start;
-
-    for (IndexT j = index_start; j < index_stop; ++j)
-    {
-      A2_col_indices[j] = j;
-      A2_elements[j] = NumericT(1);
-    }
-  }
-
-  // write last entry in row_buffer with global thread 0:
-  if (threadIdx.x == 0 && blockIdx.x == 0)
-    A2_row_indices[A2_size1] = new_row_buffer[A2_size1];
-}
-
-template<typename IndexT, typename NumericT>
-__global__ void compressed_matrix_gemm_G1(
-          IndexT * G1_row_indices,
-          IndexT * G1_col_indices,
-          NumericT * G1_elements,
-          IndexT G1_size1,
-          IndexT const *A_row_indices,
-          IndexT const *A_col_indices,
-          NumericT const *A_elements,
-          IndexT A_size1,
-          IndexT A_nnz,
-          IndexT max_per_row,
-          IndexT *new_row_buffer)
-{
-  // Part 1: Copy column indices and entries:
-  for (IndexT i = blockIdx.x * blockDim.x + threadIdx.x; i < A_nnz; i += blockDim.x * gridDim.x)
-  {
-    G1_col_indices[i] = A_col_indices[i];
-    G1_elements[i]    = A_elements[i];
-  }
-
-  // Part 2: Derive new row indicies:
-  for (IndexT i = blockIdx.x * blockDim.x + threadIdx.x; i < A_size1; i += blockDim.x * gridDim.x)
-  {
-    unsigned int old_start = A_row_indices[i];
-    unsigned int new_start = new_row_buffer[i];
-    unsigned int row_chunks = new_row_buffer[i+1] - new_start;
-
-    for (IndexT j=0; j<row_chunks; ++j)
-      G1_row_indices[new_start + j] = old_start + j * max_per_row;
-  }
-
-  // write last entry in row_buffer with global thread 0:
-  if (threadIdx.x == 0 && blockIdx.x == 0)
-    G1_row_indices[G1_size1] = A_row_indices[A_size1];
-}
-
-
-
-/** @brief Carries out sparse_matrix-sparse_matrix multiplication for CSR matrices
-*
-* Implementation of the convenience expression C = prod(A, B);
-* Based on computing C(i, :) = A(i, :) * B via merging the respective rows of B
-*
-* @param A     Left factor
-* @param B     Right factor
-* @param C     Result matrix
-*/
-template<class NumericT, unsigned int AlignmentV>
-void prod_impl(viennacl::compressed_matrix<NumericT, AlignmentV> const & A,
-               viennacl::compressed_matrix<NumericT, AlignmentV> const & B,
-               viennacl::compressed_matrix<NumericT, AlignmentV> & C)
-{
-  C.resize(A.size1(), B.size2(), false);
-
-  unsigned int blocknum = 256;
-  unsigned int threadnum = 128;
-
-  viennacl::vector<unsigned int> subwarp_sizes(blocknum, viennacl::traits::context(A)); // upper bound for the nonzeros per row encountered for each work group
-  viennacl::vector<unsigned int> max_nnz_row_A(blocknum, viennacl::traits::context(A)); // upper bound for the nonzeros per row encountered for each work group
-  viennacl::vector<unsigned int> max_nnz_row_B(blocknum, viennacl::traits::context(A)); // upper bound for the nonzeros per row encountered for each work group
-
-#ifdef VIENNACL_WITH_SPGEMM_CUDA_TIMINGS
-  viennacl::tools::timer timer;
-#endif
-
-  //
-  // Stage 1: Determine upper bound for number of nonzeros
-  //
-#ifdef VIENNACL_WITH_SPGEMM_CUDA_TIMINGS
-  cudaDeviceSynchronize();
-  timer.start();
-#endif
-
-  compressed_matrix_gemm_stage_1<<<blocknum, threadnum>>>(viennacl::cuda_arg<unsigned int>(A.handle1()),
-                                                          viennacl::cuda_arg<unsigned int>(A.handle2()),
-                                                          static_cast<unsigned int>(A.size1()),
-                                                          viennacl::cuda_arg<unsigned int>(B.handle1()),
-                                                          viennacl::cuda_arg(subwarp_sizes),
-                                                          viennacl::cuda_arg(max_nnz_row_A),
-                                                          viennacl::cuda_arg(max_nnz_row_B)
-                                                         );
-  VIENNACL_CUDA_LAST_ERROR_CHECK("compressed_matrix_gemm_stage_1");
-#ifdef VIENNACL_WITH_SPGEMM_CUDA_TIMINGS
-  cudaDeviceSynchronize();
-  std::cout << "Stage 1 device: " << timer.get() << std::endl;
-  timer.start();
-#endif
-
-  subwarp_sizes.switch_memory_context(viennacl::context(MAIN_MEMORY));
-  unsigned int * subwarp_sizes_ptr = viennacl::linalg::host_based::detail::extract_raw_pointer<unsigned int>(subwarp_sizes.handle());
-
-  max_nnz_row_A.switch_memory_context(viennacl::context(MAIN_MEMORY));
-  unsigned int const * max_nnz_row_A_ptr = viennacl::linalg::host_based::detail::extract_raw_pointer<unsigned int>(max_nnz_row_A.handle());
-
-  max_nnz_row_B.switch_memory_context(viennacl::context(MAIN_MEMORY));
-  unsigned int const * max_nnz_row_B_ptr = viennacl::linalg::host_based::detail::extract_raw_pointer<unsigned int>(max_nnz_row_B.handle());
-
-  //std::cout << "Subwarp sizes: " << subwarp_sizes << std::endl;
-
-  viennacl::vector<unsigned int> scratchpad_offsets(blocknum, viennacl::context(MAIN_MEMORY)); // upper bound for the nonzeros per row encountered for each work group
-  unsigned int * scratchpad_offsets_ptr = viennacl::linalg::host_based::detail::extract_raw_pointer<unsigned int>(scratchpad_offsets.handle());
-
-  unsigned int max_subwarp_size = 0;
-  unsigned int A_max_nnz_per_row = 0;
-  unsigned int scratchpad_offset = 0;
-  //std::cout << "Scratchpad offsets: " << std::endl;
-  for (std::size_t i=0; i<subwarp_sizes.size(); ++i)
-  {
-    max_subwarp_size = std::max(max_subwarp_size, subwarp_sizes_ptr[i]);
-    A_max_nnz_per_row = std::max(A_max_nnz_per_row, max_nnz_row_A_ptr[i]);
-
-    scratchpad_offsets_ptr[i] = scratchpad_offset;
-    //std::cout << scratchpad_offset << " (with " << (max_nnz_row_A_ptr[i] / subwarp_sizes_ptr[i] + 1) << " warp reloads per group at " << max_nnz_row_A_ptr[i] << " max rows, "
-    //                                            << upper_bound_nonzeros_per_row_C_ptr[i] << " row length, "
-    //                                            << (256 / subwarp_sizes_ptr[i]) << " warps per group " << std::endl;
-    unsigned int max_warp_reloads = max_nnz_row_A_ptr[i] / subwarp_sizes_ptr[i] + 1;
-    unsigned int max_row_length_after_warp_merge = subwarp_sizes_ptr[i] * max_nnz_row_B_ptr[i];
-    unsigned int warps_in_group = threadnum / subwarp_sizes_ptr[i];
-    scratchpad_offset +=  max_warp_reloads
-                        * max_row_length_after_warp_merge
-                        * warps_in_group;
-  }
-  //std::cout << "Scratchpad memory for indices: " << scratchpad_offset << " entries (" << scratchpad_offset * sizeof(unsigned int) * 1e-6 << " MB)" << std::endl;
-
-  if (max_subwarp_size > 32)
-  {
-    // determine augmented size:
-    unsigned int max_entries_in_G = 1024;
-    if (A_max_nnz_per_row <= 512*512)
-      max_entries_in_G = 512;
-    if (A_max_nnz_per_row <= 256*256)
-      max_entries_in_G = 256;
-    if (A_max_nnz_per_row <= 128*128)
-      max_entries_in_G = 128;
-    if (A_max_nnz_per_row <= 64*64)
-      max_entries_in_G = 64;
-
-    viennacl::vector<unsigned int> exclusive_scan_helper(A.size1() + 1, viennacl::traits::context(A));
-    compressed_matrix_gemm_decompose_1<<<blocknum, threadnum>>>(viennacl::cuda_arg<unsigned int>(A.handle1()),
-                                                                static_cast<unsigned int>(A.size1()),
-                                                                static_cast<unsigned int>(max_entries_in_G),
-                                                                viennacl::cuda_arg(exclusive_scan_helper)
-                                                               );
-    VIENNACL_CUDA_LAST_ERROR_CHECK("compressed_matrix_gemm_decompose_1");
-
-    thrust::exclusive_scan(thrust::device_ptr<unsigned int>(viennacl::cuda_arg(exclusive_scan_helper)),
-                           thrust::device_ptr<unsigned int>(viennacl::cuda_arg(exclusive_scan_helper) + exclusive_scan_helper.size()),
-                           thrust::device_ptr<unsigned int>(viennacl::cuda_arg(exclusive_scan_helper)));
-
-    unsigned int augmented_size = exclusive_scan_helper[A.size1()];
-
-    // split A = A2 * G1
-    viennacl::compressed_matrix<NumericT, AlignmentV> A2(A.size1(), augmented_size, augmented_size, viennacl::traits::context(A));
-    viennacl::compressed_matrix<NumericT, AlignmentV> G1(augmented_size, A.size2(),        A.nnz(), viennacl::traits::context(A));
-
-    // fill A2:
-    compressed_matrix_gemm_A2<<<blocknum, threadnum>>>(viennacl::cuda_arg<unsigned int>(A2.handle1()),
-                                                       viennacl::cuda_arg<unsigned int>(A2.handle2()),
-                                                       viennacl::cuda_arg<NumericT>(A2.handle()),
-                                                       static_cast<unsigned int>(A2.size1()),
-                                                       viennacl::cuda_arg(exclusive_scan_helper)
-                                                      );
-    VIENNACL_CUDA_LAST_ERROR_CHECK("compressed_matrix_gemm_A2");
-
-    // fill G1:
-    compressed_matrix_gemm_G1<<<blocknum, threadnum>>>(viennacl::cuda_arg<unsigned int>(G1.handle1()),
-                                                       viennacl::cuda_arg<unsigned int>(G1.handle2()),
-                                                       viennacl::cuda_arg<NumericT>(G1.handle()),
-                                                       static_cast<unsigned int>(G1.size1()),
-                                                       viennacl::cuda_arg<unsigned int>(A.handle1()),
-                                                       viennacl::cuda_arg<unsigned int>(A.handle2()),
-                                                       viennacl::cuda_arg<NumericT>(A.handle()),
-                                                       static_cast<unsigned int>(A.size1()),
-                                                       static_cast<unsigned int>(A.nnz()),
-                                                       static_cast<unsigned int>(max_entries_in_G),
-                                                       viennacl::cuda_arg(exclusive_scan_helper)
-                                                      );
-    VIENNACL_CUDA_LAST_ERROR_CHECK("compressed_matrix_gemm_G1");
-
-    // compute tmp = G1 * B;
-    // C = A2 * tmp;
-    viennacl::compressed_matrix<NumericT, AlignmentV> tmp(G1.size1(), B.size2(), 0, viennacl::traits::context(A));
-    prod_impl(G1, B, tmp); // this runs a standard RMerge without decomposition of G1
-    prod_impl(A2, tmp, C); // this may split A2 again
-    return;
-  }
-
-  subwarp_sizes.switch_memory_context(viennacl::traits::context(A));
-  max_nnz_row_A.switch_memory_context(viennacl::traits::context(A));
-  max_nnz_row_B.switch_memory_context(viennacl::traits::context(A));
-  scratchpad_offsets.switch_memory_context(viennacl::traits::context(A));
-
-  viennacl::vector<unsigned int> scratchpad_indices(scratchpad_offset, viennacl::traits::context(A)); // upper bound for the nonzeros per row encountered for each work group
-
-#ifdef VIENNACL_WITH_SPGEMM_CUDA_TIMINGS
-  std::cout << "Intermediate host stage: " << timer.get() << std::endl;
-  timer.start();
-#endif
-
-  //
-  // Stage 2: Determine pattern of C
-  //
-
-  compressed_matrix_gemm_stage_2<<<blocknum, threadnum>>>(viennacl::cuda_arg<unsigned int>(A.handle1()),
-                                                         viennacl::cuda_arg<unsigned int>(A.handle2()),
-                                                         static_cast<unsigned int>(A.size1()),
-                                                         viennacl::cuda_arg<unsigned int>(B.handle1()),
-                                                         viennacl::cuda_arg<unsigned int>(B.handle2()),
-                                                         static_cast<unsigned int>(B.size2()),
-                                                         viennacl::cuda_arg<unsigned int>(C.handle1()),
-                                                         viennacl::cuda_arg(subwarp_sizes),
-                                                         viennacl::cuda_arg(max_nnz_row_A),
-                                                         viennacl::cuda_arg(max_nnz_row_B),
-                                                         viennacl::cuda_arg(scratchpad_offsets),
-                                                         viennacl::cuda_arg(scratchpad_indices)
-                                                        );
-  VIENNACL_CUDA_LAST_ERROR_CHECK("compressed_matrix_gemm_stage_2");
-#ifdef VIENNACL_WITH_SPGEMM_CUDA_TIMINGS
-  cudaDeviceSynchronize();
-  std::cout << "Stage 2: " << timer.get() << std::endl;
-  timer.start();
-#endif
-
-
-  // exclusive scan on C.handle1(), ultimately allowing to allocate remaining memory for C
-  viennacl::backend::typesafe_host_array<unsigned int> row_buffer(C.handle1(), C.size1() + 1);
-  viennacl::backend::memory_read(C.handle1(), 0, row_buffer.raw_size(), row_buffer.get());
-  unsigned int current_offset = 0;
-  for (std::size_t i=0; i<C.size1(); ++i)
-  {
-    unsigned int tmp = row_buffer[i];
-    row_buffer.set(i, current_offset);
-    current_offset += tmp;
-  }
-  row_buffer.set(C.size1(), current_offset);
-  viennacl::backend::memory_write(C.handle1(), 0, row_buffer.raw_size(), row_buffer.get());
-
-
-  //
-  // Stage 3: Compute entries in C
-  //
-  C.reserve(current_offset, false);
-
-  viennacl::vector<NumericT> scratchpad_values(scratchpad_offset, viennacl::traits::context(A)); // upper bound for the nonzeros per row encountered for each work group
-
-#ifdef VIENNACL_WITH_SPGEMM_CUDA_TIMINGS
-  std::cout << "Intermediate stage 2->3: " << timer.get() << std::endl;
-  timer.start();
-#endif
-
-  compressed_matrix_gemm_stage_3<<<blocknum, threadnum>>>(viennacl::cuda_arg<unsigned int>(A.handle1()),
-                                                          viennacl::cuda_arg<unsigned int>(A.handle2()),
-                                                          viennacl::cuda_arg<NumericT>(A.handle()),
-                                                          static_cast<unsigned int>(A.size1()),
-                                                          viennacl::cuda_arg<unsigned int>(B.handle1()),
-                                                          viennacl::cuda_arg<unsigned int>(B.handle2()),
-                                                          viennacl::cuda_arg<NumericT>(B.handle()),
-                                                          static_cast<unsigned int>(B.size2()),
-                                                          viennacl::cuda_arg<unsigned int>(C.handle1()),
-                                                          viennacl::cuda_arg<unsigned int>(C.handle2()),
-                                                          viennacl::cuda_arg<NumericT>(C.handle()),
-                                                          viennacl::cuda_arg(subwarp_sizes),
-                                                          viennacl::cuda_arg(max_nnz_row_A),
-                                                          viennacl::cuda_arg(max_nnz_row_B),
-                                                          viennacl::cuda_arg(scratchpad_offsets),
-                                                          viennacl::cuda_arg(scratchpad_indices),
-                                                          viennacl::cuda_arg(scratchpad_values)
-                                                         );
-  VIENNACL_CUDA_LAST_ERROR_CHECK("compressed_matrix_gemm_stage_3");
-#ifdef VIENNACL_WITH_SPGEMM_CUDA_TIMINGS
-  cudaDeviceSynchronize();
-  std::cout << "Stage 3: " << timer.get() << std::endl;
-  std::cout << "----------" << std::endl;
-#endif
-
-}
-
-} // namespace cuda
-} //namespace linalg
-} //namespace viennacl
-
-
-#endif