On Mon, Mar 8, 2021 at 5:58 PM Catalin Marinas wrote:
>
> On Mon, Mar 08, 2021 at 04:55:14PM +0100, Andrey Konovalov wrote:
> > @@ -68,10 +69,16 @@ static inline void mte_set_mem_tag_range(void *addr,
> > size_t size, u8 tag)
> >* 'asm volatile' is required to prevent the compiler to move
> >* the statement outside of the loop.
> >*/
> > - asm volatile(__MTE_PREAMBLE "stg %0, [%0]"
> > - :
> > - : "r" (curr)
> > - : "memory");
> > + if (init)
> > + asm volatile(__MTE_PREAMBLE "stzg %0, [%0]"
> > + :
> > + : "r" (curr)
> > + : "memory");
> > + else
> > + asm volatile(__MTE_PREAMBLE "stg %0, [%0]"
> > + :
> > + : "r" (curr)
> > + : "memory");
> >
> > curr += MTE_GRANULE_SIZE;
> > } while (curr != end);
>
> Is 'init' always a built-in constant here? If not, checking it once
> outside the loop may be better (or check the code generation, maybe the
> compiler is smart enough).
I think it's worth moving the init check outside the loop anyway. Will do in v3.
Thanks!
