Re: HLL expression -> ASM

"Marco van de Voort" <marcov@stack.nl> wrote in message
> "Alexei A. Frounze" wrote:
> >
> > Now, how do I transform the tree/whatever (let's say only integer
> > values/vars involved in the expression) into an ASM piece of code w/o
> > consuming extra memory for partial results, just using CPU registers?
> > Is there any basic idea/algorithm which I'm missing? It must be
> > simple, I guess...
>
> - Did you already transform the tree so that the least number of stack
> positions are used?


Nope. How would I do that, any example where it's the case and we can
minimize the depth?


> - Is your expression FP or integer? With FP you have some more
> "registers", but watch out for built in procedures in your compiler
> (that could be the same as I'm using) that may affect the FP stack.


As I mentioned, that's for CPU, that's for (I)MUL/(I)DIV, therefore,
*integer*.


> Most expressions can be evaluated using 4 regs. The problem that for
> integer (as somebody already said) is that mul and div need specific
> registers.


I know that. But again, what would you recommend to do if I run out of
registers due to a complex expression? Should I just put something to
the stack or what?


--
Alexei A. Frounze
alexfru [AT] chat [DOT] ru
http://alexfru.chat.ru
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