Re: [Qemu-devel] [PATCH 2/2] ppc: Convert op_andi to TCG

["Blue Swirl" <blauwirbel@gmail.com>]

On 9/14/08, Paul Brook <paul@codesourcery.com> wrote:
> > > > >    tcg_gen_mov_tl(cpu_T[0], cpu_gpr[rS(ctx->opcode)]);
>  > > > > -    gen_op_andi_T0(UIMM(ctx->opcode));
>  > > > > +    tcg_gen_andi_tl(cpu_T[0], cpu_T[0], UIMM(ctx->opcode));
>  > > > >    tcg_gen_mov_tl(cpu_gpr[rA(ctx->opcode)], cpu_T[0]);
>  > > > >    gen_set_Rc0(ctx);
>  > > > >  }
>  > > >
>  > > > Small comment: this would be more optimally:
>  > > >   tcg_gen_andi_tl(cpu_gpr[rA(ctx->opcode)],
>  > > > cpu_gpr[rS(ctx->opcode)], UIMM(ctx->opcode));
>  > > >
>  > > > The same applies to andis.
>  > >
>  > >  Careful there, iirc this cannot be done before gen_set_Rc0 is converted!
>  >
>  > I didn't mean to remove gen_set_Rc0, the comment only applied to the
>  > mov+andi+mov sequence.
>
>
> set_Rc0 relies on T0 being set correctly be the preceding sequence.

I see. I just read the patch, not the affected code, sorry for the noise.