public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
From: "guihaoc at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/103784] New: suboptimal code for returning bool value on target ppc
Date: Tue, 21 Dec 2021 01:42:31 +0000 [thread overview]
Message-ID: <bug-103784-4@http.gcc.gnu.org/bugzilla/> (raw)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103784
Bug ID: 103784
Summary: suboptimal code for returning bool value on target ppc
Product: gcc
Version: 12.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: guihaoc at gcc dot gnu.org
Target Milestone: ---
//test.c
#include <stdbool.h>
bool foo (int a, int b)
{
if (a > 2)
return false;
if (b < 10)
return true;
return true;
}
//assembly with trunk
ld 9,0(3)
cmpdi 0,9,0
add 10,9,4
beq 0,.L5
ldarx 8,0,3
cmpd 0,8,9
bne 0,.L4
stdcx. 10,0,3
bne 0,.L4
li 3,1
rldicl 3,3,0,63
blr
.p2align 4,,15
.L5:
li 3,0
rldicl 3,3,0,63
blr
//assembly with at13.0
subfic 3,3,2
srdi 3,3,63
xori 3,3,0x1
blr
The second branch and two zero extend are unnecessary. If it returns a integer,
the code seems good.
//test1.c
int foo (int a, int b)
{
if (a > 2)
return 0;
if (b < 10)
return 1;
return 1;
}
//assembly with trunk
li 9,1
cmpwi 0,3,2
isel 3,0,9,1
blr
next reply other threads:[~2021-12-21 1:42 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-12-21 1:42 guihaoc at gcc dot gnu.org [this message]
2021-12-21 1:46 ` [Bug target/103784] " pinskia at gcc dot gnu.org
2021-12-21 2:35 ` guihaoc at gcc dot gnu.org
2021-12-21 2:43 ` pinskia at gcc dot gnu.org
2021-12-21 3:02 ` guihaoc at gcc dot gnu.org
2023-01-04 14:07 ` segher at gcc dot gnu.org
2023-01-04 14:08 ` segher at gcc dot gnu.org
2023-01-04 14:13 ` segher at gcc dot gnu.org
2023-01-05 16:34 ` jskumari at gcc dot gnu.org
2023-03-01 4:04 ` jskumari at gcc dot gnu.org
2023-03-05 11:48 ` jskumari at gcc dot gnu.org
2023-03-05 15:41 ` dje at gcc dot gnu.org
2023-03-05 19:27 ` segher at gcc dot gnu.org
2023-03-06 8:14 ` jskumari at gcc dot gnu.org
2023-03-16 9:52 ` rguenth at gcc dot gnu.org
2023-04-11 17:07 ` aagarwa at gcc dot gnu.org
2023-07-20 11:15 ` jskumari at gcc dot gnu.org
2023-08-31 8:03 ` aagarwa at gcc dot gnu.org
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=bug-103784-4@http.gcc.gnu.org/bugzilla/ \
--to=gcc-bugzilla@gcc.gnu.org \
--cc=gcc-bugs@gcc.gnu.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).