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Re: Inline functions called once III


> Jan Hubicka <jh at suse dot cz> writes:
> 
> > -finline-functions-called-once almost always reduces code size, so it is
> > applicable for -Os and perhaps for -O2 too.  It also may be performance
> > loss in the case programer took care to put cold stuff into spearate
> > function, so I tought it may justify special flag.
> 
> We could probably address the performance loss by additional
> branch probability heuristics: if there is a function called once, and
> its call site is in a block that is conditionally executed, give that
> block a low probability so it is moved out-of-line.

Yes, partly it can be addressed this way.  Other problem is
prologue/epilogue size so we would need shrink wrapping in order to make
inlined function always cheaper.
This does not seem to be serious, as I didn't measured any slowodnws
with this patch in practice.

Honza
> 
> zw


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