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Re: [PATCH 8/8] Use rank_for_schedule to as tie-breaker in model_order_p
- From: Maxim Kuvyrkov <maxim dot kuvyrkov at linaro dot org>
- To: Richard Sandiford <richard dot sandiford at arm dot com>
- Cc: GCC Patches <gcc-patches at gcc dot gnu dot org>, Vladimir Makarov <vmakarov at redhat dot com>
- Date: Wed, 22 Oct 2014 06:49:34 +1300
- Subject: Re: [PATCH 8/8] Use rank_for_schedule to as tie-breaker in model_order_p
- Authentication-results: sourceware.org; auth=none
- References: <9F97F273-F5DC-4E85-8298-4790ED2C9E82 at linaro dot org> <87r3y1kfjk dot fsf at e105548-lin dot cambridge dot arm dot com>
On Oct 21, 2014, at 9:11 PM, Richard Sandiford <firstname.lastname@example.org> wrote:
> Maxim Kuvyrkov <email@example.com> writes:
>> This patch improves model_order_p to use non-reg-pressure version of
>> rank_for_schedule when it needs to break the tie. At the moment it is
>> comparing INSN_PRIORITY by itself, and it seems prudent to outsource
>> that to rank_for_schedule.
> Do you have an example of where this helps? A possible danger is that
> rank_for_schedule might (indirectly) depend on state that isn't maintained
> or updated in the same way during the model schedule phase.
I don't have an example where this patch helps, and I consider this patch a general cleanup. From what I can see, all scheduler data structures are maintained during reg_sched_model scheduling.