Cheat Engine

[Twistedfate]

I know
cmp eax,0 <-----------------eax is always 0 even when the address is clearly invalid: "?? ?? ?? ??"

but how could I check if the address it self is wrong
look at the picture .
if the game go to this address will break

mov edi,[edi+00000138]
because edi value is 1 and cannot be used as correct address

so how to check the edi if contain the correct address or not .


2nd Question can I use:
pushfd
pushad
pushf
or pushfd is enough rather than pushf

[ParkourPenguin]