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Re: df.c and partial writes/REG_EQUAL notes

> Richard Henderson <> writes:
> > On Tue, Sep 25, 2001 at 11:32:40AM -0400, Daniel Berlin wrote:
> > > Your web code must be pretty slow on large test cases, since my ebitmap 
> >> patch *still* hasn't been reviewed.
> >
> > Um, no, it *has* been reviewed.  I told you how I wanted
> > it changed.
> >
> Ah, yes.
> You want no more than 2 bitmap implementations in the compiler,
> and want it replaced all at once, which is another questionable idea.
It IMO makes sense.
As the current bitmap can have advantage possibly only in extremly large and
sparse bitmaps we don't have currently (and that should be better handled by
tripple indirection or more fiting underlying datastructure than linked lists
are) and most of users to my best knowledge will benefit from the
implementation, it is wortwhile to do it.  All our bitmpas I am aware of are
maximally quadratic (regsXinstructions) or so, that should be always small
enought for ebitmap implementation.

Or do I miss something important?

In case you don't have motivation to do the step, I may try next week, as
working (and fast) dataflow is good and bitmap.c is one of top CPU hogs of
current compiler and we really need to get dataflow module working and used.
> This was your "review".
Please lets work together to get gcc better, not fight.

> >
> > r~
> -- 
> "When I was five years old I was on a merry go round.  There was
> a gunshot nearby.  The horses stampeded.  There I was running
> down the street on a purple wooden horse.
> "-Steven Wright

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