From: Liao Shihua <shihua@iscas.ac.cn>
To: gcc-patches@gcc.gnu.org
Cc: kito.cheng@gmail.com, jeffreyalaw@gmail.com, jiawei@iscas.ac.cn,
Liao Shihua <shihua@iscas.ac.cn>
Subject: [PATCH] RISC-V: Fix missing boolean_expression in zmmul extension
Date: Thu, 23 May 2024 18:45:21 +0800 [thread overview]
Message-ID: <20240523104521.328214-1-shihua@iscas.ac.cn> (raw)
Missing boolean_expression TARGET_ZMMUL in riscv_rtx_costs() casuse different instructions when multiplying an integer with a constant.
( https://github.com/riscv-collab/riscv-gnu-toolchain/issues/1482 )
int foo(int *ib) {
*ib = *ib * 33938;
return 0;
}
rv64im:
lw a4,0(a1)
li a5,32768
addiw a5,a5,1170
mulw a5,a5,a4
sw a5,0(a1)
ret
rv64i_zmmul:
lw a4,0(a1)
slliw a5,a4,5
addw a5,a5,a4
slliw a5,a5,3
addw a5,a5,a4
slliw a5,a5,3
addw a5,a5,a4
slliw a5,a5,3
addw a5,a5,a4
slliw a5,a5,1
sw a5,0(a1)
ret
Fixed.
gcc/ChangeLog:
* config/riscv/riscv.cc (riscv_rtx_costs): Add TARGET_ZMMUL.
---
gcc/config/riscv/riscv.cc | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/gcc/config/riscv/riscv.cc b/gcc/config/riscv/riscv.cc
index 85df5b7ab49..580ae007181 100644
--- a/gcc/config/riscv/riscv.cc
+++ b/gcc/config/riscv/riscv.cc
@@ -3753,7 +3753,7 @@ riscv_rtx_costs (rtx x, machine_mode mode, int outer_code, int opno ATTRIBUTE_UN
case MULT:
if (float_mode_p)
*total = tune_param->fp_mul[mode == DFmode];
- else if (!TARGET_MUL)
+ else if (!(TARGET_MUL || TARGET_ZMMUL))
/* Estimate the cost of a library call. */
*total = COSTS_N_INSNS (speed ? 32 : 6);
else if (GET_MODE_SIZE (mode).to_constant () > UNITS_PER_WORD)
--
2.34.1
next reply other threads:[~2024-05-23 10:47 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-05-23 10:45 Liao Shihua [this message]
2024-05-23 13:12 ` Kito Cheng
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=20240523104521.328214-1-shihua@iscas.ac.cn \
--to=shihua@iscas.ac.cn \
--cc=gcc-patches@gcc.gnu.org \
--cc=jeffreyalaw@gmail.com \
--cc=jiawei@iscas.ac.cn \
--cc=kito.cheng@gmail.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).