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Re: [patch]Fix the aliasing on vector replacements to match the original scalar array
> Will replace with
> FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_VMAYDEF)
> SSA_NAME_DEF_STMT (def) = *vec_stmt;
> mark_sym_for_renaming (SSA_NAME_VAR (def));
> > Also add a comment describing why we need to mark V_MAY_DEFs for
> I was very surprised that I needed to call mark_sym_for_renaming. IIRC
> peeling done in the vectorizer renamed a v-def in the loop for which there
> was a v-use outside the loop. The loop wasn't in loop-closed form, i.e.,
> wasn't a PHI node v-def.outside = v-def.inside in the exit block. I think
> modifications done by peeling try to update PHI nodes in exit blocks
> it assumes loop-closed form but looks no further. Calling
> cleared up the problem. I'll see if I can find the test again that caused
> to add the call to mark_sym_for_renaming just to make sure.
virtual operands are no longer in loop closed ssa form; thus all the
virtual defs inside loop must be marked for ssa update.