[white_beach]

here's one or two

shr ecx, 1 lea eax, [rcx + 1FC00000h] shr eax, 1 add eax, ecx

[dahart]

This reminded me of the puzzle book “xchg rax,rax”. Maybe that has some hidden insights… :P

https://www.xorpd.net/pages/xchg_rax/snip_00.html