# 00 0000
   xor eax,eax
# 01 0004
   movzx eax,al
# 02 0034
   movzx eax,ax
# 03 0234
   and eax,$00ffffff
# 04 4321
   bswap eax
# 05 0001
   shr eax,24
# 06 0012
   shr eax,16
# 07 0123
   shr eax,8
# 08 0204
   and eax,$00ff00ff
# 09 0103
   shr eax,8
   and eax,$00ff00ff
# 0a 0102
   xor ax,ax
   shr eax,8
   shr ax,8 
# 0b 0304
   movzx eax,ax
   shl eax,8
   shr ax,8
# 0c 2040
   shl eax,8
   and eax,$ff00ff00
# 0d 1030
   and eax,$ff00ff00
# 0e 1020
   xor ax,ax
   shr eax,8
   shr ax,8
   shl eax,8
# 0f 3040
   movzx eax,ax
   shl eax,8
   shr ax,8
   shl eax,8 
# 10 1243
   xchg ah,al
# 11 2134
   bswap eax
   xchg ah,al
   bswap eax
# 12 2143
   bswap eax
   ror eax,16
# 13 4231
   rol eax,8
   xchg ah,al
   ror eax,8
# 14 4123
   ror eax,8 
# 15 3412
   ror eax,16
# 16 2341
   rol eax,8
# 17 1324
   ror eax,8
   xchg ah,al
   rol eax,8
# 18 1111
   mov ah,al
   movzx ecx,ax
   shl eax,16
   or eax,ecx
# 19 2222
   mov al,ah
   movzx ecx,ax
   shl eax,16
   or eax,ecx
# 1a 3333
   shr eax,16
   mov ah,al
   movzx ecx,ax
   shl eax,16
   or eax,ecx
# 1b 4444
   shr eax,24
   mov ah,al
   movzx ecx,ax
   shl eax,16
   or eax,ecx
# 1c 3214
   bswap eax
   rol eax,8
# 1d 0404
   movzx ecx,al
   movzx eax,al
   shl eax,16
   or eax,ecx
# 1e ss34
   movsx eax,ax
# 1f sss4
   movsx eax,al
   