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Re: [PATCH, M68K] Handle -fsched-pressure
On Apr 7, 2011, at 6:55 PM, Jeff Law wrote:
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> On 04/07/11 08:29, Maxim Kuvyrkov wrote:
>> The following simple patch fixes a corner-case in m68k scheduling when -fsched-pressure is used. Currently m68k scheduling hooks assume that the scheduler honors DFA restrictions, which is not always the case when scheduling for register pressure (-fsched-pressure). The patch fixes this corner-case.
>>
>> I will commit this patch under the trivial rule in 4 days (on Monday) or sooner if I get an explicit approval.
> I guess my only concern would be whether or not this problem (buffer not
> being filled enough causing other problems) exists in any other backend.
> If it's not too much trouble, could you do a quick looksie at other
> backends that defining these hooks to see if they are obviously correct
> or incorrect?
The sched_ib buffer is an invention of mine specific to m68k backend to model bottleneck of ColdFire's memory bus, which is shared between data and instructions. This buffer does not exist outside of m68k back-end.
Jeff, does this answer your concern?
Thank you,
--
Maxim Kuvyrkov
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