------- Comment #2 from dorit at gcc dot gnu dot org 2007-08-20 05:55 ------- > Making us return symbolic stride would not be hard. The problem is that data > dependence analysis would fail anyway,
sometimes (not in this testcases) there won't be a need for dependence testing - e.g. a reduction computation where there are no stores, or initialization with a constant (i.e. a store and no loads), so there's already a value in doing this. > since we cannot tell whether n is zero. can we do the data-dependence analysis conditioned on a maybe_zero (like the number-of-iterations analysis)? (by the way, I was told that ifort vectorizes this. I think we'd need loop reversal to vectorize the inner-loop though. on top of overcoming the unknown-stride issue in the DR and DDR analysis) -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33113
