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Re: gcc optimises out test of value in register-only loop
On 10/14/2011 05:41 AM, Ian Lance Taylor wrote:
> MikeW <mw_phil@yahoo.co.uk> writes:
>
>> volatile register int stop_loop __asm("r5")__;
>
> gcc does not support volatile register variables. I think it could be
> meaningful, but it has never worked.
It would be really nasty to implement: we'd have to check for volatility
on every access to a hard register. The benefits don't seem worth it,
IMO.
Andrew.