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Re: powerpc -mcpu=common equivalent ?


On Thu, Feb 9, 2017 at 1:16 PM, Daniel Walker <danielwa@cisco.com> wrote:
> On 02/09/2017 10:08 AM, David Edelsohn wrote:
>>
>> On Thu, Feb 9, 2017 at 1:00 PM, Daniel Walker <danielwa@cisco.com> wrote:
>>>
>>> Hi,
>>>
>>>
>>> It looks like -mcpu=common (on the powerpc architecture) was removed. My
>>> group is struggling to find a way to compile generic binaries for
>>> PowerPC.
>>> We have been getting an LWSYNC instruction included in the binaries, and
>>> some of our processors are getting a trap when this instructions is
>>> executed. The platforms we are using are all Freescale, they are p2020,
>>> t1042, and 8540.
>>>
>>> Freescale support informed us that we should use -mcpu=common , which is
>>> gone, we tried a number of other -mcpu setting including -mcpu=powerpc,
>>> but
>>> none of them allow us to have generic binaries for all the platforms.
>>>
>>> I suppose this is either a bug report that we're getting lwsync when we
>>> shouldn't be getting it, or just a question of what the typical tune is
>>> to
>>> make generic binaries ?
>>
>> I think that you misunderstand what "common" meant.  Common was a
>> subset of the original IBM POWER Architecture (not POWER processor)
>> and the PowerPC architecture.
>>
>> An option that targets all Freescale processors is up to Freescale.
>>
>> Thanks, David
>
>
>
> No, I understood that. I'm not actually sure if we don't have a POWER
> architecture included. However, lwsync didn't exist in POWER, and some of
> our processors don't tolerate lwsync. Do you know of a way to compile for
> all powerpc and POWER platforms in one ? Or to compile for powerpc platforms
> which don't tolerate lwsync for some reason?

Freescale did not implement the POWER architecture.  Again, POWER is a
comment about the original IBM POWER architecture (RIOS processors)
and used in RISC System/6000 computers, not the recent POWER
processors called POWER4, POWER5, POWER6, POWER7, POWER8, POWER9.

lwsync is part of the ISA and Freescale did not fully implement the
architecture.

Freescale or someone needs to implement a patch to target the
Freescale non-compliant processors.

Thanks, David


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