[Bug rtl-optimization/42175] Slow compile and much memory use at -O1

[rakdver at kam dot mff dot cuni dot cz]

------- Comment #8 from rakdver at kam dot mff dot cuni dot cz  2010-01-03 19:37 -------
Subject: Re:  Slow compile and much memory  use
        at -O1

> ------- Comment #7 from rguenth at gcc dot gnu dot org  2010-01-03 17:03 -------
> Well, obviously it is because
> 
> template<typename T>
> gmic& gmic::parse(...)
> {
> ...
>     while (position<command_line.size() && !is_quit) {
> 
> loop body with 4000 lines of code (well, including lots of lines
> with a few thousand chars, control flow, loops and function calls)
> 
>     }
> ...
> }
> 
> and DF never was good scaling to this kind of code.  Maybe not considering
> this outermost loop in LIM will fix the slowness...  the limit is currently
> 10000 basic-blocks, maybe a little large when considering non-innermost
> loops.

10000 bbs seems way too large -- even for innermost loops.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42175