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Re: no_new_pseudos


On Jul  9, 2007, Kenneth Zadeck <zadeck@naturalbridge.com> wrote:

> Apparently there areplaces, at least in the ppc backend that did not
> generate pseudos before reload because of the abstraction that are
> now able to generate them.

I don't understand what you mean by 'because of the abstraction'.

It's true that, before your patch, one couldn't create new pseudos
after flow analysis, and after your patch, one can create them all the
way until reload.  'no_new_pseudos' would still mean the same: it's
true if it's too late to create new pseudos, and false otherwise.

That's the power of the abstraction: the internal implementation
changes, but the exposed interface still offers the same semantics,
and things that rely on the abstraction work regardless of the
change.  Which doesn't mean 'work exactly the same way'.  If the
change enables them to work even better, they do.  If it constraints
them further, then they are constrained.  But as long as the
semantics of the abstraction is unchanged, things work.

-- 
Alexandre Oliva         http://www.lsd.ic.unicamp.br/~oliva/
FSF Latin America Board Member         http://www.fsfla.org/
Red Hat Compiler Engineer   aoliva@{redhat.com, gcc.gnu.org}
Free Software Evangelist  oliva@{lsd.ic.unicamp.br, gnu.org}


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