On Thu, Jun 28, 2012 at 10:33 AM, Zhenqiang Chen <zhenqiang.c...@arm.com> wrote:
>>> diff --git a/gcc/loop-init.c b/gcc/loop-init.c index 03f8f61..5d8cf73
>>> 100644
>>> --- a/gcc/loop-init.c
>>> +++ b/gcc/loop-init.c
>>> @@ -273,6 +273,12 @@ struct rtl_opt_pass pass_rtl_loop_done =
>>> static bool
>>> gate_rtl_move_loop_invariants (void)
>>> {
>>> + /* In general, invariant motion can not reduce code size. But it
>>> + will
>>> + change the liverange of the invariant, which increases the
>>> + register
>>> + pressure and might lead to more spilling. */
>>> + if (optimize_function_for_size_p (cfun))
>>> + return false;
>>> +
>>
>>Can you do this per loop instead? Using optimize_loop_nest_for_size_p?
>
> Update it according to the comments.
>
> Thanks!
> -Zhenqiang
>
> diff --git a/gcc/loop-invariant.c b/gcc/loop-invariant.c
> index f8405dd..b0e84a7 100644
> --- a/gcc/loop-invariant.c
> +++ b/gcc/loop-invariant.c
> @@ -1931,7 +1931,8 @@ move_loop_invariants (void)
> curr_loop = loop;
> /* move_single_loop_invariants for very large loops
> is time consuming and might need a lot of memory. */
> - if (loop->num_nodes <= (unsigned) LOOP_INVARIANT_MAX_BBS_IN_LOOP)
> + if (loop->num_nodes <= (unsigned) LOOP_INVARIANT_MAX_BBS_IN_LOOP
> + && ! optimize_loop_nest_for_size_p (loop))
> move_single_loop_invariants (loop);
Wait - move_single_loop_invariants itself already uses
optimize_loop_for_speed_p.
And looking down it seems to have support for tracking spill cost (eventually
only with -fira-loop-pressure) - please work out why this support is not working
for you.
Richard.
> }
>
> ChangeLog:
> 2012-06-28 Zhenqiang Chen <zhenqiang.c...@arm.com>
>
> * loop-invariant.c (move_loop_invariants): Skip
> move_single_loop_invariants when optimizing loop for size
>
>
>
>
