[Bug tree-optimization/33319] [4.2 regression] g++.dg/tree-ssa/pr27549.C ICE with vectorization

[dorit at gcc dot gnu dot org]

------- Comment #11 from dorit at gcc dot gnu dot org  2007-11-04 04:09 -------
(In reply to comment #10)
> Doesn't fail on trunk since r129797:
> 2007-10-31  Sebastian Pop  <sebastian.pop@amd.com>
>         PR tree-optimization/32377
> ...
> before:
> pr27549.C:58: note: create runtime check for data references *D.2383_45 and
> *D.2381_41
> pr27549.C:58: note: LOOP VECTORIZED.
> after:
> pr27549.C:58: note: not vectorized, possible dependence between data-refs
> *D.2383_45 and *D.2381_41

the assumption was that the ICE was related to versioning-for-aliasing
(run-time dependence testing), which, now that the dependence-tester was fixed,
is not required anymore, but:

> Still fails on 4.2 branch.

...we don't have versioning-for-aliasing in 4.2, so this loop could not be
vectorized with 4.2 (unless our dependence tester in 4.2 is able to determine
the dependence without this fix?). Interesting.


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33319