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Re: [PATCH]: Clear SSA_NAME_DEF_STMT on released SSA names


On Fri, 2006-09-29 at 22:48 -0400, Daniel Berlin wrote:
> On 9/29/06, Daniel Berlin <dberlin@dberlin.org> wrote:

> Except we reference it as just TREE_CHAIN.
> Forget it then, i'll wait till we have SSA_NAME's where we aren't
> sharing things like this.
You can avoid this sharing by adding another pointer field to every
SSA_NAME.  That's the way it worked originally.  It's merely more
memory :-)...


It may also be worthwhile to see if recycling SSA_NAMEs is even
worth the effort these days.  Recycling was a byproduct of the 
ancient code to update the SSA graph after jump threading which
took sets of variables out of SSA form, then put them back into
SSA form -- which generated an insane churn of SSA_NAMEs.  The
SSA graph updating code, while still probably not optimal should
be churning far fewer SSA_NAMEs these days.


jeff


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