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[Bug tree-optimization/50162] [4.7 Regression] Wrong vectorization
- From: "rguenth at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>
- To: gcc-bugs at gcc dot gnu dot org
- Date: Tue, 23 Aug 2011 08:40:43 +0000
- Subject: [Bug tree-optimization/50162] [4.7 Regression] Wrong vectorization
- Auto-submitted: auto-generated
- References: <bug-50162-4@http.gcc.gnu.org/bugzilla/>
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50162
Richard Guenther <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2011-08-23
Ever Confirmed|0 |1
--- Comment #2 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-08-23 08:40:43 UTC ---
Confirmed.
The vectorizer inserts the load:
vect_var_.13_22 = MEM[(double[256] *)vect_pa.9_20];
vect_pa.9_23 = vect_pa.9_20 + 16;
vect_var_.14_24 = MEM[(double[256] *)vect_pa.9_23];
vect_pa.9_25 = vect_pa.9_23 + 16;
vect_var_.15_26 = MEM[(double[256] *)vect_pa.9_25];
vect_pa.9_27 = vect_pa.9_25 + 16;
vect_var_.16_28 = MEM[(double[256] *)vect_pa.9_27];
but nothing uses it so it gets DCEd quickly.
vect_var_.17_29 = __builtin_ia32_vec_pack_sfix (vect_var_.13_22,
vect_var_.14_24);
vect_var_.17_30 = __builtin_ia32_vec_pack_sfix (vect_var_.14_24,
vect_var_.15_26);
you can see _24 is used twice - I suppose instead _28 should appear here
somehow.