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Re: condition codes, haifa-sched and virtual-stack-vars


On Jan 30, 2002, Greg McGary <greg@mcgary.org> wrote:

> In the "movsi" expander, I added this bit:

>         if (REG_P (src)
>             && REGNO (src) >= FIRST_PSEUDO_REGISTER
>             && REGNO (src) <= LAST_VIRTUAL_REGISTER)

I'd take the last condition out.  Consider, for example, that you have
a very large stack frame, such that a pseudo ends up having to be
replaced with (plus (reg SP) (const_int VERY_LARGE_NUMBER))?  Reload
may end up using a scratch register to construct this address, and it
will need an add to do that.  Better be safe and consider any pseudo
reloading risky.


Other than that, I'm very happy it worked.

-- 
Alexandre Oliva   Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
Red Hat GCC Developer                  aoliva@{cygnus.com, redhat.com}
CS PhD student at IC-Unicamp        oliva@{lsd.ic.unicamp.br, gnu.org}
Free Software Evangelist                Professional serial bug killer


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