RE: [PATCH] [x86] Add define_insn_and_split to support general version of "kxnor".

["Liu, Hongtao" <hongtao.liu@intel.com>]

> -----Original Message-----
> From: Jakub Jelinek <jakub@redhat.com>
> Sent: Tuesday, October 11, 2022 9:59 PM
> To: Liu, Hongtao <hongtao.liu@intel.com>
> Cc: gcc-patches@gcc.gnu.org
> Subject: Re: [PATCH] [x86] Add define_insn_and_split to support general
> version of "kxnor".
> 
> On Tue, Oct 11, 2022 at 04:03:16PM +0800, liuhongt via Gcc-patches wrote:
> > gcc/ChangeLog:
> >
> > 	* config/i386/i386.md (*notxor<mode>_1): New post_reload
> > 	define_insn_and_split.
> > 	(*notxorqi_1): Ditto.
> 
> > --- a/gcc/config/i386/i386.md
> > +++ b/gcc/config/i386/i386.md
> > @@ -10826,6 +10826,39 @@ (define_insn "*<code><mode>_1"
> >     (set_attr "type" "alu, alu, msklog")
> >     (set_attr "mode" "<MODE>")])
> >
> > +(define_insn_and_split "*notxor<mode>_1"
> > +  [(set (match_operand:SWI248 0 "nonimmediate_operand" "=rm,r,?k")
> > +	(not:SWI248
> > +	  (xor:SWI248
> > +	    (match_operand:SWI248 1 "nonimmediate_operand" "%0,0,k")
> > +	    (match_operand:SWI248 2 "<general_operand>" "r<i>,<m>,k"))))
> > +   (clobber (reg:CC FLAGS_REG))]
> > +  "ix86_binary_operator_ok (XOR, <MODE>mode, operands)"
> > +  "#"
> > +  "&& reload_completed"
> > +  [(parallel
> > +    [(set (match_dup 0)
> > +	  (xor:SWI248 (match_dup 1) (match_dup 2)))
> > +     (clobber (reg:CC FLAGS_REG))])
> > +   (set (match_dup 0)
> > +	(not:SWI248 (match_dup 1)))]
> > +{
> > +  if (MASK_REGNO_P (REGNO (operands[0])))
> 
> This causes --enable-checking=yes,rtl,extra regression on
> gcc.dg/store_merging_13.c test on x86_64-linux:
> .../gcc/testsuite/gcc.dg/store_merging_13.c: In function 'f13':
> .../gcc/testsuite/gcc.dg/store_merging_13.c:189:1: internal compiler error: RTL
> check: expected code 'reg', have 'mem' in rhs_regno, at rtl.h:1932 0x7b0c8f
> rtl_check_failed_code1(rtx_def const*, rtx_code, char const*, int, char const*)
>         ../../gcc/rtl.cc:916
> 0x8e74be rhs_regno
>         ../../gcc/rtl.h:1932
> 0x9785fd rhs_regno
>         ./genrtl.h:120
> 0x9785fd gen_split_260(rtx_insn*, rtx_def**)
>         ../../gcc/config/i386/i386.md:10846
> 0x23596dc split_insns(rtx_def*, rtx_insn*)
>         ../../gcc/config/i386/i386.md:16392
> 0xfccd5a try_split(rtx_def*, rtx_insn*, int)
>         ../../gcc/emit-rtl.cc:3799
> 0x132e9d8 split_insn
>         ../../gcc/recog.cc:3384
> 0x13359d5 split_all_insns()
>         ../../gcc/recog.cc:3488
> 0x1335ae8 execute
>         ../../gcc/recog.cc:4412
> Please submit a full bug report, with preprocessed source (by using -freport-
> bug).
> Please include the complete backtrace with any bug report.
> See <https://gcc.gnu.org/bugs/> for instructions.
> 
> Fixed thusly, tested on x86_64-linux, committed to trunk as obvious.
Thanks.
> 
> 2022-10-11  Jakub Jelinek  <jakub@redhat.com>
> 
> 	PR target/107185
> 	* config/i386/i386.md (*notxor<mode>_1): Use MASK_REG_P (x)
> instead of
> 	MASK_REGNO_P (REGNO (x)).
> 
> --- gcc/config/i386/i386.md.jj	2022-10-11 12:10:42.188891134 +0200
> +++ gcc/config/i386/i386.md	2022-10-11 15:47:45.531449089 +0200
> @@ -10843,7 +10843,7 @@ (define_insn_and_split "*notxor<mode>_1"
>     (set (match_dup 0)
>  	(not:SWI248 (match_dup 0)))]
>  {
> -  if (MASK_REGNO_P (REGNO (operands[0])))
> +  if (MASK_REG_P (operands[0]))
>      {
>        emit_insn (gen_kxnor<mode> (operands[0], operands[1], operands[2]));
>        DONE;
> 
> 
> 	Jakub