> On Wed, 27 Oct 2021, Jan Hubicka wrote:
>
> > >
> > > gcc/ChangeLog:
> > >
> > > * tree-ssa-loop-split.c (split_loop): Fix incorrect probability.
> > > (do_split_loop_on_cond): Likewise.
> > > ---
> > > gcc/tree-ssa-loop-split.c | 25 -
> > > 1 file changed, 16 ins
On Wed, 27 Oct 2021, Jan Hubicka wrote:
> >
> > gcc/ChangeLog:
> >
> > * tree-ssa-loop-split.c (split_loop): Fix incorrect probability.
> > (do_split_loop_on_cond): Likewise.
> > ---
> > gcc/tree-ssa-loop-split.c | 25 -
> > 1 file changed, 16 insertions(+), 9 de
> As discussed yesterday, for loop of form
>
> for (...)
> if (cond)
> cond = something();
> else
> something2
>
> Split as
>
Say "if (cond)" has probability p, then individual statements scale as
follows:
loop1:
pfor (...)
p if (true)
1cond = something();
1
>
> gcc/ChangeLog:
>
> * tree-ssa-loop-split.c (split_loop): Fix incorrect probability.
> (do_split_loop_on_cond): Likewise.
> ---
> gcc/tree-ssa-loop-split.c | 25 -
> 1 file changed, 16 insertions(+), 9 deletions(-)
>
> diff --git a/gcc/tree-ssa-loop-split.
loop split condition is moved between loop1 and loop2, the split bb's
count and probability should also be duplicated instead of (100% vs INV),
secondly, the original loop1 and loop2 count need be propotional from the
original loop.
Regression tested pass, OK for master?
diff base/loop-cond-split
