Re: [Tinycc-devel] Proposal for handling alloca(). Anyone see a problem with it?

[David A. Wheeler]

I said:
> >Reusing stack space from different sub-blocks would be nice.  It's probably 
> >not even that hard to make better use of stack space, though I haven't 
> >looked.

Philippe Ribet:
> The initial goal of tcc is to be very fast and very small. Adding 
> optimiser capabilities will make the code bigger, harder to understand 
> and maintain, tcc runing slower... I think it will be another project.

It's a waste of time to work really hard at optimization in tcc, but I think 
that one _IS_ within the spirit of tcc, for two reasons:
* tcc _does_ include a number of optimizations, as long as they're "easy".  For 
example, it does constant folding.  I think this is another easy one.
* Fabrice Bellard made sure that tcc could boot the Linux kernel.  
Unfortunately, that probably will fail, because the Linux kernel developers are 
moving to smaller (4K) stacks exclusively.  Adding an optimization that changes 
not-working to working, esp. a for program that tcc's developer SPECIFICALLY 
supported, makes sense.

Usually optimizations just make programs a little faster.  This optimization 
may become necessary to run an important program, period.

--- David A. Wheeler