[PATCH] Fix part of pr25505

Daniel Berlin dberlin@dberlin.org
Thu Aug 31 21:10:00 GMT 2006


> I still don;t.  Just about every optimization deals with up to date
> stmts.  You have to go out of your way not to, like the renamer and
> DOM.
>
> In any case, if an optimization is dealing with out of date stmts, then
> it ought to be manipulating the trees directly since the operand cache
> isn't being used, not using FOR...OPERAND.  Its for use when the normal
> rules are being followed.
>
> Checking for SSA_NAME within the body serves no real purpose. If you are
> operating in an out-of-date state where you can get a non-ssa name, then
> you are in a state where you are likely missing information by using
> FOR...OPERAND.

I don't disagree with this. I didn't write the code in question, and
in fact I was the one that suggested it be changed.
But i'll argue it's not clearly documented that they only return
SSA_NAMES in places like tree-ssa.texi.

It only talks about operands.
It's not clear that these operands can only be SSA_NAMES.
Naming the iterator "FOR_EACH_SSA_TREE_OPERAND"  instead of
"FOR_EACH_SSA_NAME_OPERAND" doesn't really help :)


>
> Andrew
>
>



More information about the Gcc-patches mailing list