Add safe-guard for masked version

Author: byjtew

include/graphblas/reference/blas3.hpp

@@ -1327,24 +1327,26 @@ namespace grb {
 				for( auto i = start_row; i < end_row; ++i ) {
 					auto mask_k = mask_raw.col_start[ i ];
 					for( auto k = A_crs_raw.col_start[ i ]; k < A_crs_raw.col_start[ i + 1 ]; ++k ) {
-						auto k_col = A_crs_raw.row_index[ k ];
+						const auto j = A_crs_raw.row_index[ k ];
 
 						// Increment the mask pointer until we find the right column, or a lower column (since the storage withing a row is sorted in a descending order)
-						while( mask_k < mask_raw.col_start[ i + 1 ] && mask_raw.row_index[ mask_k ] > k_col  ) {
+						while( mask_k < mask_raw.col_start[ i + 1 ] && mask_raw.row_index[ mask_k ] > j  ) {
 							_DEBUG_THREADESAFE_PRINT( "NEquals masked coordinate: ( " + std::to_string( i ) + ";" + std::to_string( mask_raw.row_index[ mask_k ] ) + " )\n" );
 							mask_k++;
 						}
-							
-						if( mask_raw.row_index[ mask_k ] < k_col || not MaskHasValue< MaskType >( mask_raw, mask_k ).value ) {
-							mask_k++;
+						if( mask_k >= mask_raw.col_start[ i + 1 ] ) {
+							_DEBUG_THREADESAFE_PRINT( "No value left for this column\n" );
+							break;
+						}	
+						if( mask_raw.row_index[ mask_k ] < j || not MaskHasValue< MaskType >( mask_raw, mask_k ).value ) {
 							_DEBUG_THREADESAFE_PRINT( "Skip masked value at: ( " + std::to_string( i ) + ";" + std::to_string( mask_raw.row_index[ mask_k ] ) + " )\n" );
 							continue;
 						}
 
 						_DEBUG_THREADESAFE_PRINT( "Found masked value at: ( " + std::to_string( i ) + ";" + std::to_string( mask_raw.row_index[ mask_k ] ) + " )\n" );
 						// Get A value
 						const auto a_val_before = A_crs_raw.values[ k ];
-						_DEBUG_THREADESAFE_PRINT( "A( " + std::to_string( i ) + ";" + std::to_string( k_col ) + " ) = " + std::to_string( a_val_before ) + "\n" );
+						_DEBUG_THREADESAFE_PRINT( "A( " + std::to_string( i ) + ";" + std::to_string( j ) + " ) = " + std::to_string( a_val_before ) + "\n" );
 						// Compute the fold for this coordinate
 						local_rc = local_rc ? local_rc : grb::apply< descr >( A_crs_raw.values[ k ], a_val_before, x, op );
 						local_rc = local_rc ? local_rc : grb::apply< descr >( A_ccs_raw.values[ k ], a_val_before, x, op );