Hi Ke Wen,
On Tue, Dec 15, 2020 at 03:53:29PM +0800, Kewen.Lin wrote:
> on 2020/12/15 上午2:51, Segher Boessenkool wrote:
> > On Wed, Dec 02, 2020 at 05:44:24PM +0800, Kewen.Lin wrote:
> >> --- a/gcc/config/rs6000/rs6000.c
> >> +++ b/gcc/config/rs6000/rs6000.c
> >> @@ -6793,17 +6793,8 @@ rs6000_expand_vector_init (rtx target, rtx vals)
> >> /* Force the values into word_mode registers. */
> >> for (i = 0; i < n_elts; i++)
> >> {
> >> - rtx tmp = force_reg (GET_MODE_INNER (mode), XVECEXP (vals, 0, i));
> >> - if (TARGET_POWERPC64)
> >> - {
> >> - op[i] = gen_reg_rtx (DImode);
> >> - emit_insn (gen_zero_extendqidi2 (op[i], tmp));
> >> - }
> >> - else
> >> - {
> >> - op[i] = gen_reg_rtx (SImode);
> >> - emit_insn (gen_zero_extendqisi2 (op[i], tmp));
> >> - }
> >> + rtx tmp = force_reg (inner_mode, XVECEXP (vals, 0, i));
> >> + op[i] = simplify_gen_subreg (Pmode, tmp, inner_mode, 0);
> >> }
> >
> > Pmode is defined based on TARGET_64BIT, not TARGET_POWERPC64.
>
> Good point, you are right, is it ok to change this part with one
> explicit mode based on TARGET_POWERPC64?
>
> rtx tmp = force_reg (inner_mode, XVECEXP (vals, 0, i));
> machine_mode tmode = TARGET_POWERPC64 ? DImode : SImode;
> op[i] = simplify_gen_subreg (tmode, tmp, inner_mode, 0);
That looks fine, yes.
> > But, can you not always use SImode here?
>
> Sorry that I didn't quite follow here.
I mean do
rtx tmp = force_reg (inner_mode, XVECEXP (vals, 0, i));
op[i] = simplify_gen_subreg (SImode, tmp, inner_mode, 0);
If that works (also in 64-bit mode), that is preferred. It might need
some more adjustment elsewhere, not sure if that is worth it.
It is okay for trunk with either of those changes. Thanks!
Segher
