[Bug rtl-optimization/98782] [11/12 Regression] Bad interaction between IPA frequences and IRA resulting in spills due to changes in BB frequencies

[hubicka at kam dot mff.cuni.cz]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98782

--- Comment #26 from hubicka at kam dot mff.cuni.cz ---
> It's with LTO, I'll see if non-LTO has the same benefit.  In terms of code-size
> it looks like it accounts for a 20% increase for binary size, but the hot
> function shrinks approx 6x. But of course this increase covers the entire
> binaries and there are other hot functions like GetVirtualPixelsFromNexus that
> also shrink significantly when specialized.
Thanks.  I will check this.  We mey need tweaking cost model to first
specialize the functions that reduce more (by doing multiple passes with
decreasing threshold)

It is really nice to see some real improvmeents from ipa-cp. For years
the pass did almost nothing on the benchmarks I tested (spec, Firefox,
clang) but it has changed.  I also see measurable speedups on clang
binary with ipa-cp on.