FPU advise needed - SOLVED -

[Spocks-cuddly-tribble]

Hi friends,


whilst fixing a hidden/biased minor race feature, I also implemented normal minor pop growth.


(...)


Now to the problem:

I'm not familiar with the FPU handling and how it affects stacks (esp?)
(google didn't help to a non-programmer, as least not within a realistic timeframe)

(...)

With some useful hints on the issue, I could finish this project next weekend (no code space issue, still over 100 bytes free).

[Flocke]

I'm not familiar with the FPU handling and how it affects stacks (esp?)
(google didn't help to a non-programmer, as least not within a realistic timeframe)

Hi SCT,
I'm not familar with FPU arithmetic either, but doing a quick search I found a nice description: http://runtime-basic.net/Assembler:Schn ... U-Register (german)

first the fpu only operates on special fpu registers which are organized as a stack and not the esp
second all operators ending with a p seam to pop the first register st0 in fpu stack

so fmul st(1), st means st1 = st1 * st0
and fmulp st(1), st means st0 = st1 * st0 cause st1 becomes st0 after the pop

lateron fstp qword ptr [esp] stores the result st0 but also pops the stack again so st0 gets lost

fistp dword ptr [esp+1A8h] stores whatever is in st0 fpu register after the two preceding function calls as integer

hope this already helps
only referring to what you've posted

edit: oh, forgot FMUL dword ptr [esp+160h] multiplying st0 by a float and FILD dWORD [systInfo+40h] pushing the fpu stack and loading a signed integer in st0