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Re: Which POWER implementations need the HWCAP_DFP check?


Florian Weimer <fweimer@redhat.com> writes:

> On 05/14/2018 09:09 PM, Tulio Magno Quites Machado Filho wrote:
>>> I would have suggested something like
>>>
>>> #define DL_HWCAP_HAS_DFP (GLRO(dl_hwcap) & PPC_FEATURE_HAS_DFP)
>>>
>>> in the general powerpc sysdeps file, and
>>>
>>> #define DL_HWCAP_HAS_DFP 1
>>>
>>> for power6 (which I expect will propagate upwards).  I expect that this
>>> will result in somewhat nicer machine code, too.
>
>> It's safe to use the newer mtfsf in both cases.  The extra fields from the
>> new mtfsf are ignored by older processors.
>
> But couldn't dropping the conditional have impact on other processors? 
> Then we should do that only for POWER6 and later.

Agreed.

-- 
Tulio Magno


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