Left-hand tensor indexes used for lookups in the right-hand side of Expression templates

[braxtoncuneo]

On the latest version of the develop branch (f8c702cb116841ed43229f70f1deb75ca98acd15), when compiling with gcc-8.1.0 for TOSS3, the following program

#include "RAJA/RAJA.hpp"
#include "camp/camp.hpp"

int main (int argc, char* argv[])
{

    double A[2] = { 1, 2 };

    double B[16] = {
           1,    1,    1,    1,
          10,   10,   10,   10,
         100,  100,  100,  100,
        1000, 1000, 1000, 1000
    };

    double C[16] = {
         0, 0, 0, 0,
         0, 0, 0, 0,
         0, 0, 0, 0,
         0, 0, 0, 0
    };


    using mat_t = RAJA::expt::RectMatrixRegister<double, RAJA::expt::RowMajorLayout, 4, 4, RAJA::avx2_register>;
    using row_t = RAJA::expt::RowIndex<int, mat_t>;
    using col_t = RAJA::expt::ColIndex<int, mat_t>;

    using vec_t = RAJA::expt::VectorRegister<double>;
    using idx_t = RAJA::expt::VectorIndex<int, vec_t>;

    auto aa = RAJA::View<double, RAJA::Layout<2>>  ( A, 1, 2 );

    auto bb = RAJA::View<double, RAJA::Layout<2>>  ( B, 4, 4 );

    auto cc = RAJA::View<double, RAJA::Layout<2>>  ( C, 4, 4 );

    auto rall = row_t::all();
    auto call = col_t::all();

    cc(row_t::range(0,1),call) = aa(0,0) * bb(row_t::range(0,1),call);
    cc(row_t::range(1,2),call) = aa(0,1) * bb(row_t::range(0,1),call);
    cc(row_t::range(2,3),call) = aa(0,0) * bb(row_t::range(1,2),call);
    cc(row_t::range(3,4),call) = aa(0,1) * bb(row_t::range(1,2),call);

    for(int i=0; i<4; i++){
        for(int j=0; j<4; j++){
            printf("%f\t",cc(i,j));
        }
        printf("\n");
    }
}

reports the following matrix as a result:

[   1,   1,   1,   1]

[  20,  20,  20,  20]

[ 100, 100, 100, 100]

[2000,2000,2000,2000]

However, the correct result would be:

[   1,   1,   1,   1]

[   2,   2,   2,   2]

[  10,  10,  10,  10]

[  20,  20,  20,  20]

It appears that the row tensor index provided for the left-hand side of the assignment (cc) is being used to look up rows for the second operand in the right-hand side (bb).

[braxtoncuneo]

@ajkunen