Re: [Qemu-devel] [PATCH v4 01/18] tcg-arm: Fix local stack frame

[Peter Maydell]

On 30 March 2013 21:19, Richard Henderson <address@hidden> wrote:
> On 2013-03-30 14:14, Peter Maydell wrote:
>>
>> If you're doing a sub sp, sp, #n anyway, you might as well
>> add 4 to that and drop the save/load of r12 from the stmdb/ldmia.
>> It was only in there to save having an extra sub/add insn.
>
> Fair enough, not that it ought to make a difference to the cycle
> count.

Yeah, the TRMs suggest the ARM9 was the last to do ldm/stm
at 32 bits per cycle, and I'm guessing the prologue isn't
actually a sufficiently hot path to be worth worrying about
individual cycles anyway. I just felt it would be a bit tidier.

-- PMM