(size example eq 2) evaluates to TRUE (0FFFFFFFFh)
(size example eq 4) evaluates to FALSE (0)
MASM will try to optimise, so 83 FB FF uses the signed byte version of CMP (think of 0FFFFFFFFh as -1)
and uses OR EBX,EBX which is shorter than CMP EBX,0
00000000 81 FB FFFFFFFF cmp ebx,0ffffffffh
00000006 83 FB FF cmp ebx,-1