http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45810
Tobias Burnus <burnus at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |hubicka at gcc dot gnu.org
--- Comment #3 from Tobias Burnus <burnus at gcc dot gnu.org> 2010-09-28
12:23:06 UTC ---
(In reply to comment #2)
> For single-file programs -fwhole-program and -flto should be basically
> equivalent if the Frontend provides correctly merged decls. I suppose
> it does not and thus we do less inlining with -fwhole-program compared
> to -flto.
It might well be the reason that one does less inlining without LTO - but
that's then not only a FE bug (not correctly merged decls) but also a ME/target
bug as the LTO program is _slower_.
Cf. also PR 44334, which is about a -fwhole-program slowdown (w/ and w/o
-flto). For the latter program, it helped to use "--param
hot-bb-frequency-fraction=2000". However, for this PR, the option does not seem
to help.
