On Tue, Oct 15, 2024 at 4:07 AM Andrew Pinski <quic_apin...@quicinc.com> wrote: > > This FIXME: > FIXME: Aggressive mode before PRE doesn't work currently because > the dominance info is not invalidated after DCE1. > > Has not been true since at least r0-104723-g5ac60b564faa85 which > added a call to calculate_dominance_info. Plus we run agressive mode > before PRE since r0-89162-g11b08ee9118d10 too. And since > r0-95499-gb5b8b0ac643d31, > dominance information was required even for non-agressive mode. > > Also we have been verifying dominance information is correct and not needing > to invalidate > since ssa branch was merged so this comment has been out of date even before > it was merged in.
OK. > gcc/ChangeLog: > > * tree-ssa-dce.cc (perform_tree_ssa_dce): Remove FIXME note. > > Signed-off-by: Andrew Pinski <quic_apin...@quicinc.com> > --- > gcc/tree-ssa-dce.cc | 8 +------- > 1 file changed, 1 insertion(+), 7 deletions(-) > > diff --git a/gcc/tree-ssa-dce.cc b/gcc/tree-ssa-dce.cc > index 3075459e25f..015c17984e1 100644 > --- a/gcc/tree-ssa-dce.cc > +++ b/gcc/tree-ssa-dce.cc > @@ -1965,13 +1965,7 @@ make_forwarders_with_degenerate_phis (function *fn) > In conservative mode, we ignore control dependence and simply declare > all but the most trivially dead branches necessary. This mode is fast. > In aggressive mode, control dependences are taken into account, which > - results in more dead code elimination, but at the cost of some time. > - > - FIXME: Aggressive mode before PRE doesn't work currently because > - the dominance info is not invalidated after DCE1. This is > - not an issue right now because we only run aggressive DCE > - as the last tree SSA pass, but keep this in mind when you > - start experimenting with pass ordering. */ > + results in more dead code elimination, but at the cost of some time. */ > > static unsigned int > perform_tree_ssa_dce (bool aggressive) > -- > 2.43.0 >
