[PATCH] MIPS: Optimize atomic memory operations for TARGET_OCTEON.

[David Daney]

Richard Sandiford wrote:
> Richard Sandiford <rdsandiford@googlemail.com> writes:
>> David Daney <ddaney@caviumnetworks.com> writes:
>>> 	* gcc/config/mips/mips.c (mips_process_sync_loop) Emit syncw
>>> 	instructions for TARGET_OCTEON.
>> OK.
>>
>> Thanks for the great comment btw.
> 
> Hmm, actually, I might have been too quick off the mark.
> __sync*_compare_and_swap are documented as being full barriers even
> in the case where no SC occurs, so I think you also need to check
> "required_oldval == 0".

Yes, unfortunately I think you are correct.  Although most applications 
probably don't care, we are stuck with the specification as written.

I will test a new patch.

David Daney