Re: [PATCH v6 02/14] target/riscv: rvk: add support for zbkb extension

[Richard Henderson]

On 2/27/22 17:02, Weiwei Li wrote:
> Thanks for your comments.
>
> 在 2022/2/28 上午2:47, Richard Henderson 写道:
> > On 2/27/22 04:25, Weiwei Li wrote:
> > > +static void gen_packh(TCGv ret, TCGv src1, TCGv src2)
> > > +{
> > > +    TCGv t = tcg_temp_new();
> > > +
> > > +    tcg_gen_ext8u_tl(t, src2);
> > > +    tcg_gen_deposit_tl(ret, src1, t, 8, TARGET_LONG_BITS - 8);
> > > +    tcg_temp_free(t);
> > > +}
> > > +
> > > +static void gen_packw(TCGv ret, TCGv src1, TCGv src2)
> > > +{
> > > +    TCGv t = tcg_temp_new();
> > > +
> > > +    tcg_gen_ext16s_tl(t, src2);
> > > +    tcg_gen_deposit_tl(ret, src1, t, 16, 48);
> > > +    tcg_temp_free(t);
> > > +}
> >
> > Missing TARGET_LONG_BITS here; would break on RV32.
> packw is RV64-only instruction. Is it necessary to use TARGET_LONG_BITS here?

Ah, I see.  So it's not buggy, as-is, but it certainly looks odd next to the previous, and 
it wouldn't be buggy to use TARGET_LONG_BITS either.

This points out that it would be a good idea to keep these generator functions next to the 
trans function that uses them, for context.


r~