From: Bill Schmidt <wschmidt@linux.ibm.com>
To: HAO CHEN GUI <guihaoc@linux.ibm.com>,
gcc-patches <gcc-patches@gcc.gnu.org>
Cc: David <dje.gcc@gmail.com>,
Segher Boessenkool <segher@kernel.crashing.org>
Subject: Re: PATCH, rs6000] Optimization for vec_xl_sext
Date: Thu, 14 Oct 2021 11:58:39 -0500 [thread overview]
Message-ID: <5217146a-5344-6565-bd52-9115b410f456@linux.ibm.com> (raw)
In-Reply-To: <9c39ac50-aee1-b50f-dfb3-badb6752e921@linux.ibm.com>
Hi Haochen,
The patch looks okay to me now. Will defer to David for final call. :-)
Thanks!
Bill
On 10/14/21 1:17 AM, HAO CHEN GUI wrote:
> Hi,
>
> The patch optimizes the code generation for vec_xl_sext builtin. Now all the sign extensions are done on VSX registers directly.
>
> Bootstrapped and tested on powerpc64le-linux with no regressions. Is this okay for trunk? Any recommendations? Thanks a lot.
>
> I refined the patch according to Bill and David's advice. I put the patch.diff and ChangeLog in attachment also in case the indentation doesn't show correctly in email body.
>
>
> ChangeLog
>
> 2021-10-11 Haochen Gui <guihaoc@linux.ibm.com>
>
>
> gcc/
>
> * config/rs6000/rs6000-call.c (altivec_expand_lxvr_builtin):
>
> Modify the expansion for sign extension. All extensions are done
>
> within VSX registers.
>
>
> gcc/testsuite/
>
> * gcc.target/powerpc/p10_vec_xl_sext.c: New test.
>
> patch.diff
>
> diff --git a/gcc/config/rs6000/rs6000-call.c b/gcc/config/rs6000/rs6000-call.c
> index b4e13af4dc6..587e9fa2a2a 100644
> --- a/gcc/config/rs6000/rs6000-call.c
> +++ b/gcc/config/rs6000/rs6000-call.c
> @@ -9779,7 +9779,7 @@ altivec_expand_lxvr_builtin (enum insn_code icode, tree exp, rtx target, bool bl
>
> if (sign_extend)
> {
> - rtx discratch = gen_reg_rtx (DImode);
> + rtx discratch = gen_reg_rtx (V2DImode);
> rtx tiscratch = gen_reg_rtx (TImode);
>
> /* Emit the lxvr*x insn. */
> @@ -9788,20 +9788,31 @@ altivec_expand_lxvr_builtin (enum insn_code icode, tree exp, rtx target, bool bl
> return 0;
> emit_insn (pat);
>
> - /* Emit a sign extension from QI,HI,WI to double (DI). */
> - rtx scratch = gen_lowpart (smode, tiscratch);
> + /* Emit a sign extension from V16QI,V8HI,V4SI to V2DI. */
> + rtx temp1, temp2;
> if (icode == CODE_FOR_vsx_lxvrbx)
> - emit_insn (gen_extendqidi2 (discratch, scratch));
> + {
> + temp1 = simplify_gen_subreg (V16QImode, tiscratch, TImode, 0);
> + emit_insn (gen_vsx_sign_extend_qi_v2di (discratch, temp1));
> + }
> else if (icode == CODE_FOR_vsx_lxvrhx)
> - emit_insn (gen_extendhidi2 (discratch, scratch));
> + {
> + temp1 = simplify_gen_subreg (V8HImode, tiscratch, TImode, 0);
> + emit_insn (gen_vsx_sign_extend_hi_v2di (discratch, temp1));
> + }
> else if (icode == CODE_FOR_vsx_lxvrwx)
> - emit_insn (gen_extendsidi2 (discratch, scratch));
> - /* Assign discratch directly if scratch is already DI. */
> - if (icode == CODE_FOR_vsx_lxvrdx)
> - discratch = scratch;
> + {
> + temp1 = simplify_gen_subreg (V4SImode, tiscratch, TImode, 0);
> + emit_insn (gen_vsx_sign_extend_si_v2di (discratch, temp1));
> + }
> + else if (icode == CODE_FOR_vsx_lxvrdx)
> + discratch = simplify_gen_subreg (V2DImode, tiscratch, TImode, 0);
> + else
> + gcc_unreachable ();
>
> - /* Emit the sign extension from DI (double) to TI (quad). */
> - emit_insn (gen_extendditi2 (target, discratch));
> + /* Emit the sign extension from V2DI (double) to TI (quad). */
> + temp2 = simplify_gen_subreg (TImode, discratch, V2DImode, 0);
> + emit_insn (gen_extendditi2_vector (target, temp2));
>
> return target;
> }
> diff --git a/gcc/testsuite/gcc.target/powerpc/p10_vec_xl_sext.c b/gcc/testsuite/gcc.target/powerpc/p10_vec_xl_sext.c
> new file mode 100644
> index 00000000000..78e72ac5425
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/powerpc/p10_vec_xl_sext.c
> @@ -0,0 +1,35 @@
> +/* { dg-do compile } */
> +/* { dg-require-effective-target int128 } */
> +/* { dg-require-effective-target power10_ok } */
> +/* { dg-options "-mdejagnu-cpu=power10 -O2" } */
> +
> +#include <altivec.h>
> +
> +vector signed __int128
> +foo1 (signed long a, signed char *b)
> +{
> + return vec_xl_sext (a, b);
> +}
> +
> +vector signed __int128
> +foo2 (signed long a, signed short *b)
> +{
> + return vec_xl_sext (a, b);
> +}
> +
> +vector signed __int128
> +foo3 (signed long a, signed int *b)
> +{
> + return vec_xl_sext (a, b);
> +}
> +
> +vector signed __int128
> +foo4 (signed long a, signed long *b)
> +{
> + return vec_xl_sext (a, b);
> +}
> +
> +/* { dg-final { scan-assembler-times {\mvextsd2q\M} 4 } } */
> +/* { dg-final { scan-assembler-times {\mvextsb2d\M} 1 } } */
> +/* { dg-final { scan-assembler-times {\mvextsh2d\M} 1 } } */
> +/* { dg-final { scan-assembler-times {\mvextsw2d\M} 1 } } */
next prev parent reply other threads:[~2021-10-14 16:58 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-10-14 6:17 HAO CHEN GUI
2021-10-14 16:58 ` Bill Schmidt [this message]
2021-10-14 18:53 ` David Edelsohn
2021-10-19 9:01 ` HAO CHEN GUI
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=5217146a-5344-6565-bd52-9115b410f456@linux.ibm.com \
--to=wschmidt@linux.ibm.com \
--cc=dje.gcc@gmail.com \
--cc=gcc-patches@gcc.gnu.org \
--cc=guihaoc@linux.ibm.com \
--cc=segher@kernel.crashing.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).