Ping^1 [PATCH, rs6000] new split pattern for TI to V1TI move [PR103124]

[HAO CHEN GUI <guihaoc@linux.ibm.com>]

Hi,

    Gentle ping this:
	https://gcc.gnu.org/pipermail/gcc-patches/2021-December/587051.html

Thanks

On 17/12/2021 上午 9:55, HAO CHEN GUI wrote:
> Hi,
>    This patch defines a new split pattern for TI to V1TI move. The pattern concatenates two subreg:DI of
> a TI to a V2DI. With the pattern, the subreg pass can do register split for TI when there is a TI to V1TI
> move. The patch optimizes one unnecessary "mr" out on P9. The new test case illustrates it.
> 
>    Bootstrapped and tested on powerpc64-linux BE and LE with no regressions. Is this okay for trunk?
> Any recommendations? Thanks a lot.
> 
> ChangeLog
> 2021-12-13 Haochen Gui <guihaoc@linux.ibm.com>
> 
> gcc/
> 	* config/rs6000/vsx.md (split pattern for TI to V1TI move): Defined.
> 
> gcc/testsuite/
> 	* gcc.target/powerpc/pr103124.c: New testcase.
> 
> 
> patch.diff
> diff --git a/gcc/config/rs6000/vsx.md b/gcc/config/rs6000/vsx.md
> index bf033e31c1c..52968eb4609 100644
> --- a/gcc/config/rs6000/vsx.md
> +++ b/gcc/config/rs6000/vsx.md
> @@ -6589,3 +6589,19 @@ (define_insn "xxeval"
>     [(set_attr "type" "vecperm")
>      (set_attr "prefixed" "yes")])
> 
> +;; Construct V1TI by vsx_concat_v2di
> +(define_split
> +  [(set (match_operand:V1TI 0 "vsx_register_operand")
> +	(subreg:V1TI
> +	  (match_operand:TI 1 "int_reg_operand") 0 ))]
> +  "TARGET_P9_VECTOR && !reload_completed"
> +  [(const_int 0)]
> +{
> +  rtx tmp1 = simplify_gen_subreg (DImode, operands[1], TImode, 0);
> +  rtx tmp2 = simplify_gen_subreg (DImode, operands[1], TImode, 8);
> +  rtx tmp3 = gen_reg_rtx (V2DImode);
> +  emit_insn (gen_vsx_concat_v2di (tmp3, tmp1, tmp2));
> +  rtx tmp4 = simplify_gen_subreg (V1TImode, tmp3, V2DImode, 0);
> +  emit_move_insn (operands[0], tmp4);
> +  DONE;
> +})
> diff --git a/gcc/testsuite/gcc.target/powerpc/pr103124.c b/gcc/testsuite/gcc.target/powerpc/pr103124.c
> new file mode 100644
> index 00000000000..e9072d19b8e
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/powerpc/pr103124.c
> @@ -0,0 +1,12 @@
> +/* { dg-do compile } */
> +/* { dg-require-effective-target powerpc_p9vector_ok } */
> +/* { dg-require-effective-target int128 } */
> +/* { dg-options "-O2 -mdejagnu-cpu=power9" } */
> +/* { dg-final { scan-assembler-not "\mmr\M" } } */
> +
> +vector __int128 add (long long a)
> +{
> +  vector __int128 b;
> +  b = (vector __int128) {a};
> +  return b;
> +}
>