[Bug tree-optimization/32075] can't determine dependence between p->a[x+i] and p->a[x+i+1] where x is invariant but defined in the function

["dorit at il dot ibm dot com" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #2 from dorit at il dot ibm dot com  2007-06-18 11:03 -------
I see this in the vectorizer dump file (with mainline from a few days ago):

(compute_affine_dependence
  (stmt_a =
D.3027_19 = p_7->a[D.3026_18])
  (stmt_b =
p_7->a[D.3025_17] = D.3027_19)
Data ref a:
(Data Ref:
  stmt: D.3027_19 = p_7->a[D.3026_18];
  ref: p_7->a[D.3026_18];
  base_object: p_7->a[0];
  Access function 0: {x1_5 + 1, +, 1}_2
  Access function 1: 0B
)
Data ref b:
(Data Ref:
  stmt: p_7->a[D.3025_17] = D.3027_19;
  ref: p_7->a[D.3025_17];
  base_object: p_7->a[0];
  Access function 0: {x1_5, +, 1}_2
  Access function 1: 0B
)
affine dependence test not usable: access function not affine or constant.
(dependence classified: scev_not_known)
)

(In reply to comment #1)
> Ok, I have a patch for this issue, I am going to test it with -ftree-vectorize

so how is that coming along? do you think it will also address PRs
32375/6/7/8/9 ?


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32075