[Bug tree-optimization/94125] [9/10 Regression] wrong code at -O3 on x86_64-linux-gnu

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94125

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |amker at gcc dot gnu.org

--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> ---
Hm, it computes a dependence distance of two and in the end sorts partitions
in the wrong order from a bogus partition dependence edge.  The odd thing is
that for

  for (int c = 0; c <= 2; c++)
    {
      b = f;
      *g = k[c + 3];
      k[c + 1] = 0;
    }

we compute a distance of minus two (two + DDR_REVERSED_P) but in both
cases we need to use the same partition ordering, memset after the
partition containing the k[c+3] load but the partition dependence code
from the DDRs appearant different direction handles both cases differently.

Something is missing here.  Not sure what - Bin, any idea?