http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46248
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |ebotcazou at gcc dot
| |gnu.org, jakub at gcc dot
| |gnu.org
--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> 2010-11-01
10:34:53 UTC ---
if (added_sets_1)
{
rtx t = i1pat;
if (i0_feeds_i1_n)
t = subst (t, i0dest, i0src, 0, 0);
XVECEXP (newpat, 0, --total_sets) = t;
}
if (added_sets_2)
{
rtx t = i2pat;
if (i0_feeds_i2_n)
t = subst (t, i0dest, i0src, 0, 0);
if (i1_feeds_i2_n)
t = subst (t, i1dest, i1src, 0, 0);
if (i0_feeds_i1_n && i1_feeds_i2_n) <==============
t = subst (t, i0dest, i0src, 0, 0); <==============
XVECEXP (newpat, 0, --total_sets) = t;
}
The two lines above are problematic, because subst may clobber the first
argument's expression and
newpat = subst (newpat, i0dest, i0src, 0,
i0_feeds_i1_n && i0dest_in_i0src);
actually clobbered not just newpat, but also i1src which was in it. Not sure
if we actually can rely it always happened say if substed_i0 is true and not do
the i0dest -> i0src replacement in i2pat here.
