Re: [PATCH] Fix optimization regression in constant folder

[Michael Matz <matz at suse dot de>]

Hi,

On Sun, 14 Oct 2007, Richard Kenner wrote:

> > The point is the current situation is 1) confusing 2) redundant 3) a 
> > mess (IMHO).
> 
> It's not confusing to me and it's been this way for decades.  There's a 
> major burden that must be met on a proposal to change it.

But it wasn't you who fixed the last dozen bugs which involved sizetypes 
in some way or another.  It was Richard G., and for some of those fixes I 
sat besides him, and we know that sizetypes _definitely_ are a problem for 
the middle-end because of their peculiar semantics.  No matter if you 
agree or not agree that the semantics, in so far as they exist, are 
peculiar.  I.e. I question your assertion that you _really_ understand 
where sizetypes are involved or not, or should be involved.  A point to 
support that is http://gcc.gnu.org/ml/gcc-patches/2007-10/msg00038.html , 
where you couldn't even be bothered to look at the current GCC sources 
yourself, to look for where sizetypes should have been used too.  They 
aren't special cased in any of the new optimization passes, new being 
something like newer than 5 years.  And that trend will continue as long 
as sizetypes stay in their current form.

> No.  I want the optimizations to correctly take into account a flag 
> that's been around for decades.

Well, obviously that flag was ignored for exactly that long already by 
everyone ever producing a transformation, except for the one introducing 
it and hacking it into fold-const.c .  That doesn't exactly speak for (1) 
the necessity and (2) clarity of the flag.


Ciao,
Michael.