riscv unalignment access

source: https://gist.github.com/teknoraver/36f471ef97d4c6a6cb11148e72f9e975
# for u in 0 1; do for s in 1 2 4 8 ; do unalign_check 1024 $u $s; echo ;done ; done


ALIGNED ACCESSES

size:           1024 Mb
read size:      8 bit
unalignment:    0 byte
elapsed time:   4.63 sec
throughput:     221.23 Mb/s

size:           1024 Mb
read size:      16 bit
unalignment:    0 byte
elapsed time:   1.40 sec
throughput:     729.13 Mb/s

size:           1024 Mb
read size:      32 bit
unalignment:    0 byte
elapsed time:   1.40 sec
throughput:     731.35 Mb/s

size:           1024 Mb
read size:      64 bit
unalignment:    0 byte
elapsed time:   0.86 sec
throughput:     1190.93 Mb/s


UNALIGNED ACCESSES

size:           1024 Mb
read size:      16 bit
unalignment:    1 byte
elapsed time:   206.96 sec
throughput:     4.95 Mb/s

size:           1024 Mb
read size:      32 bit
unalignment:    1 byte
elapsed time:   133.86 sec
throughput:     7.65 Mb/s

size:           1024 Mb
read size:      64 bit
unalignment:    1 byte
elapsed time:   93.46 sec
throughput:     10.96 Mb/s