Re: [PATCH v4 3/3] m68k: track syscalls being traced with shallow user context stack

Greg Ungerer
2021-07-26T14:27:40Z

On 26/7/21 7:00 am, Linus Torvalds wrote:
> On Sun, Jul 25, 2021 at 1:48 PM Michael Schmitz <schmitzmic@gmail.com> wrote:
>>
>> Just out of interest - what would be the correct way to set/clear a
>> single bit on Coldfire? Add/subtract the 1<<bit value?
>
> I think BSET/BCLR are the way to go.

Yep, they are available on all ColdFire revisions.
I think they are the best choice here.

> Or, alternatively, put the constant in a register, and use a longword
> memory access. The arithmetic ops don't do immediates _and_ memory
> operands in Coldfire, and they don't do byte ops.
>
> Or something like that.

Yes, that is right with one exception. You can use addq with immediates
of value 1 to 8 with memory operands.

Regards
Greg