Function spgemmreuse_work_estimation 

pub fn spgemmreuse_work_estimation(
    ctx: &Context,
    op_a: Operation,
    op_b: Operation,
    matrix_a: &SparseMatrixDescriptor<'_>,
    matrix_b: &SparseMatrixDescriptor<'_>,
    matrix_c: &mut SparseMatrixDescriptor<'_>,
    algorithm: SpGemmAlgorithm,
    descriptor: &SpGemmDescriptor,
    external_buffer1: Option<DevicePtr>,
) -> Result<usize>