> This adds missing code to correctly set the counts of the exit blocks we
> create when building the CFG for a vectorized early break loop.
>
> Tested as a series on aarch64-linux-gnu, arm-linux-gnueabihf, and
> x86_64-linux-gnu. OK for trunk?
>
> Thanks,
> Alex
>
> gcc/ChangeLog:
>
> PR tree-optimization/117790
> * tree-vect-loop-manip.cc (slpeel_tree_duplicate_loop_to_edge_cfg):
> Set profile counts for {main,alt}_loop_exit_block.
> ---
> gcc/tree-vect-loop-manip.cc | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/gcc/tree-vect-loop-manip.cc b/gcc/tree-vect-loop-manip.cc
> index 5d1b70aea43..53d36eaa25f 100644
> --- a/gcc/tree-vect-loop-manip.cc
> +++ b/gcc/tree-vect-loop-manip.cc
> @@ -1686,6 +1686,16 @@ slpeel_tree_duplicate_loop_to_edge_cfg (class loop
> *loop, edge loop_exit,
>
> set_immediate_dominator (CDI_DOMINATORS, new_preheader,
> loop->header);
> +
> + /* Fix up the profile counts of the new exit blocks.
> + main_loop_exit_block was created by duplicating the
> + preheader, so needs its count scaling according to the main
> + exit edge's probability. The remaining count from the
> + preheader goes to the alt_loop_exit_block, since all
> + alternative exits have been redirected there. */
> + main_loop_exit_block->count = loop_exit->count ();
> + alt_loop_exit_block->count
> + = preheader->count - main_loop_exit_block->count;
Reading the code, we orignaly have new_preheader that is split into
several pieces and loop exits are redirected to them and exit edges of
pieces are redirected to the last part?
In that case patch is OK.
Honza
