[Bug target/20625] [4.0/4.1 regression] ivopts produces code that generates "unaligned access exception"

["rakdver at atrey dot karlin dot mff dot cuni dot cz" <gcc-bugzilla at gcc dot gnu dot org>]

------- Additional Comments From rakdver at atrey dot karlin dot mff dot cuni dot cz  2005-03-29 20:47 -------
Subject: Re:  [4.0/4.1 regression] ivopts produces code that generates "unaligned access exception"

> This most likely can be reproduced on ia64 too and other targets where alignment is needed for some 
> loads.
> 
> The tree which we produce looks like:
> <bb 0>:
>   if (p->c[0] != 0) goto <L0>; else goto <L2>;
> 
> <L0>:;
>   D.1133 = *((unsigned char *) p + 5B);
>   p = p + 1B;
>   if (D.1133 != 0) goto <L0>; else goto <L2>;

The problem seems to be that the expansion assumes that p must be
aligned.  Which seems to be reasonable.  I will try making ivopts
produce all pointer ivs in (void *) type, that should hopefully
help.


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20625