[Bug tree-optimization/34708] Inlining heuristics issue

[rguenther at suse dot de]

------- Comment #6 from rguenther at suse dot de  2008-01-08 12:21 -------
Subject: Re:  Inlining heuristics issue

On Tue, 8 Jan 2008, hubicka at ucw dot cz wrote:

> ------- Comment #5 from hubicka at ucw dot cz  2008-01-08 12:15 -------
> Subject: Re:  Inlining heuristics issue
> 
> > I think we want to account PHI nodes as real copies instead (d->count +=
> > PHI_NUM_ARGS (...)) -- if they involve real operands (not VOPs).
> 
> We ignore cost of MODIFY_EXPR in assumption that it will get quite
> likely optimized out (that is important for simple containers).  So
> ignoring PHI nodes is consistent in this manner, but on the other hand
> PHIs are less often in containers and more likely to stay after
> inlining.  I will add code for that.

Well, while register copies are likely to be optimized out, by definition
a PHI node copy cannot be optimized out (unless, of course, clever
optimization applies).

Richard.


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34708