On Tue, Mar 16, 2021 at 2:04 AM Andreas Schwab <schwab@linux-m68k.org> wrote:
>
> On Mär 15 2021, Carlos O'Donell via Libc-alpha wrote:
>
> > Then we try to fix this with the new sequence:
> >
> >   asm volatile ("movq %q0,%%fs:%P1" :
> >               : "i" ((uint64_t) cast_to_integer (value)),
> >                 "i" (offsetof (struct pthread, member)));
> >
> > Note that "%q0" is a machine constraint for any register.
>
> An operand modifier isn't a constraint.  It does not change what the
> compiler matches for the operand, it only modifies the way the operand
> is output.  'q' has no meaning for an operand matched by the 'i'
> constraint, since that is never a register.

That is correct.

Since movq takes a register or a signed 32-bit immediate source operand,
select the immediate source operand only if it is known to be 32-bit
signed immediate at compile-time.

Here is the v5 patch with a testcase.  OK for master?

Thanks.

--
H.J.