mov      ecx,eax
and      ecx,0xffff0000
shr      ecx,0x10
and      eax,0x0000ffff
shl      eax,0x10
or       eax,ecx

mov      ecx,eax
and      ecx,0xff00ff00
shr      ecx,0x8
and      eax,0x00ff00ff
shl      eax,0x8
or       eax,ecx

mov      ecx,eax
and      ecx,0xcccccccc
shr      ecx,0x2
and      eax,0x33333333
shl      eax,0x2
or       eax,ecx

mov      ecx,eax
and      ecx,0xf0f0f0f0
shr      ecx,0x4
and      eax,0x0f0f0f0f
shl      eax,0x4
or       eax,ecx

mov      ecx,eax
and      ecx,0xaaaaaaaa
shr      ecx,0x1
and      eax,0x55555555
shl      eax,0x1
or       eax,ecx