Re: [Qemu-devel] [PATCH v6 10/50] tcg: Avoid loops against variable bounds

[Richard Henderson]

On 10/17/2017 03:03 PM, Emilio G. Cota wrote:
> On Mon, Oct 16, 2017 at 10:25:29 -0700, Richard Henderson wrote:
>> From: Richard Henderson <address@hidden>
>>
>> Copy s->nb_globals or s->nb_temps to a local variable for the purposes
>> of iteration.  This should allow the compiler to use low-overhead
>> looping constructs on some hosts.
>>
>> Reviewed-by: Alex Bennée <address@hidden>
>> Signed-off-by: Richard Henderson <address@hidden>
> 
> Reviewed-by: Emilio G. Cota <address@hidden>
> 
> FWIW on a Skylake host I couldn't measure a difference. However, the
> generated code is indeed slightly different.

I wouldn't expect so.  Low-overhead loops are more of a ppc thing.


r~