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Re: RFC: PR rtl-optimization/44695: [4.6 Regression] ice in simplify_subreg, at simplify-rtx.c:5117

On Fri, 2010-07-02 at 08:55 +0200, Paolo Bonzini wrote:
> On Fri, Jul 2, 2010 at 02:35, H.J. Lu <hjl.tools@gmail.com> wrote:
> > On Wed, Jun 30, 2010 at 11:59 PM, Paolo Bonzini <bonzini@gnu.org> wrote:
> >> This is wrong. GCC may use this for a 16 to 8 bit division and cause a
> >> divide overflow.
> >>
> >
> > Bernd suggested to use truncate:QI to avoid this.
> 
> Right, this is even suggested by the manual!  Thanks.  Uros or Bernd,
> can you approve this?

Yes, the patch is OK.

H.J., can you please move gen_rtx_{DIV,UDIV,MOD,UMOD} closer to the
place where they are used? It took me some scrolling up and down to see
where they are added as a REG_EQUAL. IMO, a blank line also wouldn't
hurt at that place.

Thanks,
Uros.
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