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SubjectRe: [PATCH 06/14] MIPS: entry: Remove unneeded need_resched() loop
On Thu, 14 Mar 2019, Paul Burton wrote:

> > @@ -66,7 +65,7 @@ need_resched:
> > andi t0, 1
> > beqz t0, restore_all
> > jal preempt_schedule_irq
> > - b need_resched
> > + j restore_all
>
> One nit - why change from branch to jump? It's not a big deal, but I'd
> prefer we stick with the branch ("b") instruction for a few reasons:
>
> - restore_all is nearby so there's no issue with it being out of range
> of a branch in any variation of the MIPS ISA.

FYI, if it does go out of range for whatever reason, then for non-PIC
code GAS will relax it to a jump anyway (with a relocation attached); for
the regular MIPS ISA that is, where it has been doing that since forever
(I meant to implement this for the microMIPS ISA too, but IIRC there was a
complication there, probably coming from the existing more complex branch
relaxation code and/or slightly different use of relocations, and then it
fell through the cracks).

Maciej

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