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Re: [patch] PR15242
On Jan 27, 2005 02:54 PM, Paolo Bonzini <firstname.lastname@example.org> wrote:
> 1) Are you sure you want !optimize_size?
> 300% slowdowns are not
> something small, and such computed goto code can be found in embedded
> software using -Os.
A couple of kilobytes less is also not easily found. For my Prolog
test case, the object file grows >12% (back to 3.2-days sizes) with
> 2) Also, it does not seem particularly expensive given that it only
> affects a wide minority of functions (for others, it's just a single
> FOR_EACH_BB iteration).
> if (flag_expensive_optimizations || (optimize && !optimize_size))
> (i.e. only do it with -Os -fexpensive-optimization, or with -O)
> would be better?
Also fine by me, but if you don't mind, I'm not going to do the
testing for that. I really don't think you'd do -Os and then
worry about speed. Especially because those large slowdowns are
only for cases with very many computed gotos (and I suspect,
mostly for targets with branch target buffers, which you would
not typically find in embedded chips, /meguesses).