From: Chenghui Pan <panchenghui@loongson.cn>
To: gcc-patches@gcc.gnu.org
Cc: xry111@xry111.site, i@xen0n.name, chenglulu@loongson.cn,
xuchenghua@loongson.cn, Chenghui Pan <panchenghui@loongson.cn>
Subject: [PATCH v1] LoongArch: Remove masking process for operand 3 of xvpermi.q.
Date: Tue, 12 Mar 2024 09:56:58 +0800 [thread overview]
Message-ID: <20240312015658.2400338-1-panchenghui@loongson.cn> (raw)
The behavior of non-zero unused bits in xvpermi.q instruction's
third operand is undefined on LoongArch, according to our
discussion (https://github.com/llvm/llvm-project/pull/83540),
we think that keeping original insn operand as unmodified
state is better solution.
This patch partially reverts 7b158e036a95b1ab40793dd53bed7dbd770ffdaf.
gcc/ChangeLog:
* config/loongarch/lasx.md: Remove masking of operand 3.
gcc/testsuite/ChangeLog:
* gcc.target/loongarch/vector/lasx/lasx-xvpermi_q.c:
Reposition operand 3's value into instruction's defined accept range.
---
gcc/config/loongarch/lasx.md | 5 -----
.../gcc.target/loongarch/vector/lasx/lasx-xvpermi_q.c | 6 +++---
2 files changed, 3 insertions(+), 8 deletions(-)
diff --git a/gcc/config/loongarch/lasx.md b/gcc/config/loongarch/lasx.md
index ac84db7f0ce..3f25c0c1756 100644
--- a/gcc/config/loongarch/lasx.md
+++ b/gcc/config/loongarch/lasx.md
@@ -640,8 +640,6 @@ (define_insn "lasx_xvpermi_d_<mode>_1"
(set_attr "mode" "<MODE>")])
;; xvpermi.q
-;; Unused bits in operands[3] need be set to 0 to avoid
-;; causing undefined behavior on LA464.
(define_insn "lasx_xvpermi_q_<LASX:mode>"
[(set (match_operand:LASX 0 "register_operand" "=f")
(unspec:LASX
@@ -651,9 +649,6 @@ (define_insn "lasx_xvpermi_q_<LASX:mode>"
UNSPEC_LASX_XVPERMI_Q))]
"ISA_HAS_LASX"
{
- int mask = 0x33;
- mask &= INTVAL (operands[3]);
- operands[3] = GEN_INT (mask);
return "xvpermi.q\t%u0,%u2,%3";
}
[(set_attr "type" "simd_splat")
diff --git a/gcc/testsuite/gcc.target/loongarch/vector/lasx/lasx-xvpermi_q.c b/gcc/testsuite/gcc.target/loongarch/vector/lasx/lasx-xvpermi_q.c
index dbc29d2fb22..f89dfc31120 100644
--- a/gcc/testsuite/gcc.target/loongarch/vector/lasx/lasx-xvpermi_q.c
+++ b/gcc/testsuite/gcc.target/loongarch/vector/lasx/lasx-xvpermi_q.c
@@ -27,7 +27,7 @@ main ()
*((unsigned long*)& __m256i_result[2]) = 0x7fff7fff7fff0000;
*((unsigned long*)& __m256i_result[1]) = 0x7fe37fe3001d001d;
*((unsigned long*)& __m256i_result[0]) = 0x7fff7fff7fff0000;
- __m256i_out = __lasx_xvpermi_q (__m256i_op0, __m256i_op1, 0x2a);
+ __m256i_out = __lasx_xvpermi_q (__m256i_op0, __m256i_op1, 0x22);
ASSERTEQ_64 (__LINE__, __m256i_result, __m256i_out);
*((unsigned long*)& __m256i_op0[3]) = 0x0000000000000000;
@@ -42,7 +42,7 @@ main ()
*((unsigned long*)& __m256i_result[2]) = 0x000000000019001c;
*((unsigned long*)& __m256i_result[1]) = 0x0000000000000000;
*((unsigned long*)& __m256i_result[0]) = 0x00000000000001fe;
- __m256i_out = __lasx_xvpermi_q (__m256i_op0, __m256i_op1, 0xb9);
+ __m256i_out = __lasx_xvpermi_q (__m256i_op0, __m256i_op1, 0x31);
ASSERTEQ_64 (__LINE__, __m256i_result, __m256i_out);
*((unsigned long*)& __m256i_op0[3]) = 0x00ff00ff00ff00ff;
@@ -57,7 +57,7 @@ main ()
*((unsigned long*)& __m256i_result[2]) = 0xffff0000ffff0000;
*((unsigned long*)& __m256i_result[1]) = 0x00ff00ff00ff00ff;
*((unsigned long*)& __m256i_result[0]) = 0x00ff00ff00ff00ff;
- __m256i_out = __lasx_xvpermi_q (__m256i_op0, __m256i_op1, 0xca);
+ __m256i_out = __lasx_xvpermi_q (__m256i_op0, __m256i_op1, 0x02);
ASSERTEQ_64 (__LINE__, __m256i_result, __m256i_out);
return 0;
--
2.39.3
next reply other threads:[~2024-03-12 1:57 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-03-12 1:56 Chenghui Pan [this message]
2024-03-13 12:42 ` Xi Ruoyao
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=20240312015658.2400338-1-panchenghui@loongson.cn \
--to=panchenghui@loongson.cn \
--cc=chenglulu@loongson.cn \
--cc=gcc-patches@gcc.gnu.org \
--cc=i@xen0n.name \
--cc=xry111@xry111.site \
--cc=xuchenghua@loongson.cn \
/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).