Re: [PATCH v6, rs6000] Implemented f[min/max]_optab by xs[min/max]dp [PR103605]

["Kewen.Lin" <linkw@linux.ibm.com>]

Hi Haochen,

on 2022/6/24 10:02, HAO CHEN GUI wrote:
> Hi,
>   This patch implements optab f[min/max]_optab by xs[min/max]dp on rs6000.
> Tests show that outputs of xs[min/max]dp are consistent with the standard
> of C99 fmin/max.
> 
>   This patch also binds __builtin_vsx_xs[min/max]dp to fmin/max instead
> of smin/max. So the builtins always generate xs[min/max]dp on all
> platforms.
> 
>   Bootstrapped and tested on ppc64 Linux BE and LE with no regressions.
> Is this okay for trunk? Any recommendations? Thanks a lot.
> 
> ChangeLog
> 2022-06-24 Haochen Gui <guihaoc@linux.ibm.com>
> 
> gcc/
> 	PR target/103605
> 	* config/rs6000/rs6000.md (FMINMAX): New.
> 	(minmax_op): New.
> 	(f<minmax_op><mode>3): New pattern by UNSPEC_FMAX and UNSPEC_FMIN.

Nit: here miss UNSPEC_FMAX and UNSPEC_FMIN.

> 	* config/rs6000/rs6000-builtins.def (__builtin_vsx_xsmaxdp): Set
> 	pattern to fmaxdf3.
> 	(__builtin_vsx_xsmindp): Set pattern to fmindf3.
> 
> gcc/testsuite/
> 	PR target/103605
> 	* gcc.dg/powerpc/pr103605.c: New.
> 
> 
> patch.diff
> diff --git a/gcc/config/rs6000/rs6000-builtins.def b/gcc/config/rs6000/rs6000-builtins.def
> index f4a9f24bcc5..8b735493b40 100644
> --- a/gcc/config/rs6000/rs6000-builtins.def
> +++ b/gcc/config/rs6000/rs6000-builtins.def
> @@ -1613,10 +1613,10 @@
>      XSCVSPDP vsx_xscvspdp {}
> 
>    const double __builtin_vsx_xsmaxdp (double, double);
> -    XSMAXDP smaxdf3 {}
> +    XSMAXDP fmaxdf3 {}
> 
>    const double __builtin_vsx_xsmindp (double, double);
> -    XSMINDP smindf3 {}
> +    XSMINDP fmindf3 {}
> 
>    const double __builtin_vsx_xsrdpi (double);
>      XSRDPI vsx_xsrdpi {}
> diff --git a/gcc/config/rs6000/rs6000.md b/gcc/config/rs6000/rs6000.md
> index bf85baa5370..ae0dd98f0f9 100644
> --- a/gcc/config/rs6000/rs6000.md
> +++ b/gcc/config/rs6000/rs6000.md
> @@ -158,6 +158,8 @@ (define_c_enum "unspec"
>     UNSPEC_HASHCHK
>     UNSPEC_XXSPLTIDP_CONST
>     UNSPEC_XXSPLTIW_CONST
> +   UNSPEC_FMAX
> +   UNSPEC_FMIN
>    ])
> 
>  ;;
> @@ -5341,6 +5343,22 @@ (define_insn_and_split "*s<minmax><mode>3_fpr"
>    DONE;
>  })
> 
> +
> +(define_int_iterator FMINMAX [UNSPEC_FMAX UNSPEC_FMIN])
> +
> +(define_int_attr  minmax_op [(UNSPEC_FMAX "max")
> +			     (UNSPEC_FMIN "min")])
> +
> +(define_insn "f<minmax_op><mode>3"
> +  [(set (match_operand:SFDF 0 "vsx_register_operand" "=wa")
> +	(unspec:SFDF [(match_operand:SFDF 1 "vsx_register_operand" "wa")
> +		      (match_operand:SFDF 2 "vsx_register_operand" "wa")]
> +		     FMINMAX))]
> +  "TARGET_VSX && !flag_finite_math_only"
> +  "xs<minmax_op>dp %x0,%x1,%x2"
> +  [(set_attr "type" "fp")]
> +)
> +
>  (define_expand "mov<mode>cc"
>     [(set (match_operand:GPR 0 "gpc_reg_operand")
>  	 (if_then_else:GPR (match_operand 1 "comparison_operator")
> diff --git a/gcc/testsuite/gcc.target/powerpc/pr103605.c b/gcc/testsuite/gcc.target/powerpc/pr103605.c
> new file mode 100644
> index 00000000000..1c938d40e61
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/powerpc/pr103605.c
> @@ -0,0 +1,37 @@
> +/* { dg-do compile } */

Nit: This dg-do line isn't needed.  OK with or without two nits fixed.  Thanks!

BR,
Kewen