../../source/row_neon64.cc:456:17: note: use constraint modifier "w"
    "subs       %4, %4, #8                     \n"
                ^~
                %w4

../../util/psnr.cc:90:17: note: use constraint modifier "w"
    "subs       %2, %2, #16                    \n"
                ^~
                %w2
../../source/compare_neon64.cc:35:17: note: use constraint modifier "w"
    "subs       %2, %2, #16                    \n"
                ^~
                %w2

../../source/scale_neon64.cc:77:21: note: use constraint modifier "w"
    "subs       %3, %3, #16                    \n"  // 16 processed per loop
                    ^~
                    %w3