Has anyone made good use of it? It seems to be a blessing since it sets the EFLAGS directly from floating point comparisms but is there anything I should beware of before using it?
Well, it should be noted that this instruction doesn't effect the sign flag.
I had a nasty error using the wrong branch - took forever to find!
I had a nasty error using the wrong branch - took forever to find!
Adding a little bit more to what bitRAKE said:
You may treat fcomi as fcom/fnswst/lahf in one step. So, you will get PF/ZF/CF only, just as you get when you do it in the old way. One big advantage of fcomi is that it does not trash ax, let alone the speed improvement.
You may treat fcomi as fcom/fnswst/lahf in one step. So, you will get PF/ZF/CF only, just as you get when you do it in the old way. One big advantage of fcomi is that it does not trash ax, let alone the speed improvement.