Re: [Qemu-devel] [PATCH v4 5/5] target/mips: Refactor and fix INSERT.<B|H|W|D> instructions

[Mateja Marjanovic]

On 2.4.19. 22:50, Aleksandar Markovic wrote:
> > From: Mateja Marjanovic <address@hidden>
> > Subject: [PATCH v4 5/5] target/mips: Refactor and fix INSERT.<B|H|W|D> 
> > instructions
> >
> > From: Mateja Marjanovic <address@hidden>
> >
> > The old version of the helper for the INSERT.<B|H|W|D> MSA instructions
> > has been replaced with four helpers that don't use switch, and change
> > the endianness of the given index, when executed on a big endian host.
> >
> > Signed-off-by: Mateja Marjanovic <address@hidden>
> > ---
> ...
>
>
> > +    n %= 16;
> Mateja, could you just clarify what is the purpose of this line (and
> similar three lines involving "%=")? It looks to me that n is already
> limited here to be between 0 and 15, isn't it? (that follows from the
> source code of gen_msa_elm().) What made you insert this line,
> as it stands?

It was

n %= DF_ELEMENTS(df);

but when I deleted the df argument, so it had to be done like
this. I think it's a matter of precaution (in case a number
greater than 15, or 8... is passed as an argument).

> Thanks,
> Aleksandar

Thanks,
Mateja