[patch] PR15242
Paolo Bonzini
paolo.bonzini@lu.unisi.ch
Thu Jan 27 13:55:00 GMT 2005
> + /* Aggressively duplicate basic blocks ending in computed gotos to the
> + tails of their predecessors, unless we are optimizing for size. */
> + if (flag_expensive_optimizations && !optimize_size)
> + duplicate_computed_gotos ();
A couple of things:
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.
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).
Maybe
if (flag_expensive_optimizations || (optimize && !optimize_size))
(i.e. only do it with -Os -fexpensive-optimization, or with -O) would be
better?
Paolo
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