No ifcvt during ce1 pass (fails i386/ssefp-2.c)

[Steven Bosscher]

On 3/15/07, Steven Bosscher <stevenb.gcc@gmail.com> wrote:
> On 3/15/07, Uros Bizjak <ubizjak@gmail.com> wrote:
> > The testcase is:
> >
> > double x;
> > q()
> > {
> >   x=x<5?5:x;
> > }
> >
> > compile this with -O2 -msse2 -mfpmath=sse, and this testcase should
> > compile to maxsd.
>
> This happens because a "fallthrough edge" is meaningless in cfglayout
> mode, but ifcvt.c still gives special meaning to the fallthrough edge.
>  This should not matter, but it does for some reason, and I'm
> investigating this right now. I'll try to come up with a fix asap.

This is what my fix will probably look like.  I've bootstrapped C only
on x86_64 and I have verified that it restores the CE1 transformation
for your test case.  I'll do a full bootstrap with testing over the
weekend. Early comments welcome ;-)

Gr.
Steven
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