From: HAO CHEN GUI <guihaoc@linux.ibm.com>
To: gcc-patches <gcc-patches@gcc.gnu.org>
Cc: Segher Boessenkool <segher@kernel.crashing.org>,
David <dje.gcc@gmail.com>, "Kewen.Lin" <linkw@linux.ibm.com>,
Peter Bergner <bergner@linux.ibm.com>,
xionghuluo@tencent.com
Subject: [PATCH-2, rs6000] Reverse V8HI on Power8 by vector rotation [PR100866]
Date: Mon, 24 Oct 2022 11:14:20 +0800 [thread overview]
Message-ID: <a4b84496-105a-200f-3a88-2b0a33ce638d@linux.ibm.com> (raw)
Hi,
This patch implements V8HI byte reverse on Power8 by vector rotation.
It should be effecient than orignial vector permute. The patch comes from
Xionghu's comments in PR. I just added a test case for it.
Bootstrapped and tested on ppc64 Linux BE and LE with no regressions.
Is this okay for trunk? Any recommendations? Thanks a lot.
ChangeLog
2022-10-24 Xionghu Luo <xionghuluo@tencent.com>
gcc/
PR target/100866
* config/rs6000/altivec.md: (*altivec_vrl<VI_char>): Named to...
(altivec_vrl<VI_char>): ...this.
* config/rs6000/vsx.md (revb_<mode>): Call vspltish and vrlh when
target is Power8 and mode is V8HI.
gcc/testsuite/
PR target/100866
* gcc.target/powerpc/pr100866-2.c: New.
patch.diff
diff --git a/gcc/config/rs6000/altivec.md b/gcc/config/rs6000/altivec.md
index 2c4940f2e21..84660073f32 100644
--- a/gcc/config/rs6000/altivec.md
+++ b/gcc/config/rs6000/altivec.md
@@ -1875,7 +1875,7 @@ (define_insn "altivec_vpku<VI_char>um_direct"
}
[(set_attr "type" "vecperm")])
-(define_insn "*altivec_vrl<VI_char>"
+(define_insn "altivec_vrl<VI_char>"
[(set (match_operand:VI2 0 "register_operand" "=v")
(rotate:VI2 (match_operand:VI2 1 "register_operand" "v")
(match_operand:VI2 2 "register_operand" "v")))]
diff --git a/gcc/config/rs6000/vsx.md b/gcc/config/rs6000/vsx.md
index e226a93bbe5..34662a7252d 100644
--- a/gcc/config/rs6000/vsx.md
+++ b/gcc/config/rs6000/vsx.md
@@ -6092,12 +6092,21 @@ (define_expand "revb_<mode>"
emit_insn (gen_p9_xxbr<VSX_XXBR>_<mode> (operands[0], operands[1]));
else
{
- /* Want to have the elements in reverse order relative
- to the endian mode in use, i.e. in LE mode, put elements
- in BE order. */
- rtx sel = swap_endian_selector_for_mode(<MODE>mode);
- emit_insn (gen_altivec_vperm_<mode> (operands[0], operands[1],
- operands[1], sel));
+ if (<MODE>mode == V8HImode)
+ {
+ rtx splt = gen_reg_rtx (V8HImode);
+ emit_insn (gen_altivec_vspltish (splt, GEN_INT (8)));
+ emit_insn (gen_altivec_vrlh (operands[0], operands[1], splt));
+ }
+ else
+ {
+ /* Want to have the elements in reverse order relative
+ to the endian mode in use, i.e. in LE mode, put elements
+ in BE order. */
+ rtx sel = swap_endian_selector_for_mode (<MODE>mode);
+ emit_insn (gen_altivec_vperm_<mode> (operands[0], operands[1],
+ operands[1], sel));
+ }
}
DONE;
diff --git a/gcc/testsuite/gcc.target/powerpc/pr100866-2.c b/gcc/testsuite/gcc.target/powerpc/pr100866-2.c
new file mode 100644
index 00000000000..4357d1beb09
--- /dev/null
+++ b/gcc/testsuite/gcc.target/powerpc/pr100866-2.c
@@ -0,0 +1,13 @@
+/* { dg-do compile } */
+/* { dg-require-effective-target powerpc_p8vector_ok } */
+/* { dg-options "-O2 -mdejagnu-cpu=power8" } */
+/* { dg-final { scan-assembler {\mvspltish\M} } } */
+/* { dg-final { scan-assembler {\mvrlh\M} } } */
+
+#include <altivec.h>
+
+vector unsigned short revb(vector unsigned short a)
+{
+ return vec_revb(a);
+}
+
next reply other threads:[~2022-10-24 3:14 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-24 3:14 HAO CHEN GUI [this message]
2022-10-24 21:40 ` Segher Boessenkool
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=a4b84496-105a-200f-3a88-2b0a33ce638d@linux.ibm.com \
--to=guihaoc@linux.ibm.com \
--cc=bergner@linux.ibm.com \
--cc=dje.gcc@gmail.com \
--cc=gcc-patches@gcc.gnu.org \
--cc=linkw@linux.ibm.com \
--cc=segher@kernel.crashing.org \
--cc=xionghuluo@tencent.com \
/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).