[Bug tree-optimization/53693] [4.7/4.8 regression] ICE in vect_get_vec_def_for_stmt_copy, at tree-vect-stmts.c:1438

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53693

--- Comment #4 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-06-18 
10:56:23 UTC ---
Fact is we detect

  D.2215_20 = (int) gh_18;
  D.2216_21 = D.2215_20 << 5;
  D.2217_22 = (signed short) D.2216_21;

but do not see the use

  D.2222_27 = D.2211_15 - D.2215_20;

for some reason and thus set STMT_IN_PATTER_P on the D.2215_20 def and fail
to vectorize it.  I am testing a patch.