Re: [RFC PATCH v3 01/44] target/loongarch: Add LSX data type VReg

[Song Gao]

在 2023/4/24 上午3:41, Richard Henderson 写道:
> On 4/20/23 09:06, Song Gao wrote:
> > diff --git a/target/loongarch/machine.c b/target/loongarch/machine.c
> > index b1e523ea72..a67b735a32 100644
> > --- a/target/loongarch/machine.c
> > +++ b/target/loongarch/machine.c
> > @@ -10,6 +10,112 @@
> >   #include "migration/cpu.h"
> >   #include "internals.h"
> >   +/* FPU state */
> > +static int get_fpr(QEMUFile *f, void *pv, size_t size,
> > +                   const VMStateField *field)
> > +{
> > +    fpr_t *v = pv;
> > +
> > +    qemu_get_sbe64s(f, &v->vreg.D(0));
> > +    return 0;
> > +}
> > +
> > +static int put_fpr(QEMUFile *f, void *pv, size_t size,
> > +                   const VMStateField *field, JSONWriter *vmdesc)
> > +{
> > +    fpr_t *v = pv;
> > +
> > +    qemu_put_sbe64s(f, &v->vreg.D(0));
> > +    return 0;
> > +}
> > +
> > +static const VMStateInfo vmstate_info_fpr = {
> > +    .name = "fpr",
> > +    .get  = get_fpr,
> > +    .put  = put_fpr,
> > +};
>
> These functions are old style.
> Compare target/i386/machine.c, vmstate_xmm_reg.
>
> I notice you're migrating the same data twice, between fpu and lsx.
> Compare target/i386/machine.c, vmstate_ymmh_reg, for migrating only 
> the upper half with lsx. 
Got it .
> I assume lsx without fpu is not a valid cpu configuration?
Yes.
> >   const VMStateDescription vmstate_loongarch_cpu = {
> >       .name = "cpu",
> >       .version_id = 0,
> >       .minimum_version_id = 0,
> >       .fields = (VMStateField[]) {
> > -
> >           VMSTATE_UINTTL_ARRAY(env.gpr, LoongArchCPU, 32),
> >           VMSTATE_UINTTL(env.pc, LoongArchCPU),
> > -        VMSTATE_UINT64_ARRAY(env.fpr, LoongArchCPU, 32),
> > -        VMSTATE_UINT32(env.fcsr0, LoongArchCPU),
> > -        VMSTATE_BOOL_ARRAY(env.cf, LoongArchCPU, 8),
> >             /* Remaining CSRs */
> >           VMSTATE_UINT64(env.CSR_CRMD, LoongArchCPU),
> > @@ -99,4 +200,8 @@ const VMStateDescription vmstate_loongarch_cpu = {
> >             VMSTATE_END_OF_LIST()
> >       },
> > +    .subsections = (const VMStateDescription*[]) {
> > +        &vmstate_fpu,
> > +        &vmstate_lsx,
> > +    }
>
> Need to increment version_id and minimum_version_id.
OK.

Thanks.
Song Gao