From: Borislav Petkov <bp@amd64.org>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Borislav Petkov <bp@amd64.org>, Michal Marek <mmarek@suse.cz>,
linux-kbuild <linux-kbuild@vger.kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Andrew Morton <akpm@linux-foundation.org>,
Wu Fengguang <fengguang.wu@intel.com>,
LKML <linux-kernel@vger.kernel.org>,
Jamie Lokier <jamie@shareable.org>,
Roland Dreier <rdreier@cisco.com>,
Al Viro <viro@ZenIV.linux.org.uk>,
"linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
Ingo Molnar <mingo@elte.hu>, Brian Gerst <brgerst@gmail.com>
Subject: Re: [PATCH] x86: Add optimized popcnt variants
Date: Tue, 23 Feb 2010 18:54:57 +0100 [thread overview]
Message-ID: <20100223175457.GA2401@aftab> (raw)
In-Reply-To: <4B84118C.90203@zytor.com>
From: "H. Peter Anvin" <hpa@zytor.com>
Date: Tue, Feb 23, 2010 at 09:34:04AM -0800
> On 02/23/2010 07:58 AM, Borislav Petkov wrote:
> >
> >Hmm, we cannot do that with the current design since __arch_hweight64
> >is being inlined into every callsite and AFAICT we would have to build
> >every callsite with "-fcall-saved-rdi" which is clearly too much. The
> >explicit "=D" dummy constraint is straightforward, instead.
> >
>
> Uh... the -fcall-saved-rdi would go with all the other ones.
> Assuming it can actually work and that gcc doesn't choke on an
> inbound argument being saved.
Right, doh. Ok, just added it and it builds fine with a gcc (Gentoo
4.4.1 p1.0) 4.4.1. If you have suspicion that some older gcc versions
might choke on it, I could leave the "=D" dummy constraint in?
BTW, the current version screams
/usr/src/linux-2.6/arch/x86/include/asm/arch_hweight.h: In function ‘__arch_hweight64’:
/usr/src/linux-2.6/arch/x86/include/asm/arch_hweight.h:47: warning: unused variable ‘dummy’
on x86-32. I'll send a fixed version in a second.
--
Regards/Gruss,
Boris.
-
Advanced Micro Devices, Inc.
Operating Systems Research Center
--
To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
next prev parent reply other threads:[~2010-02-23 17:54 UTC|newest]
Thread overview: 81+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-01-30 9:45 [PATCH 0/5] [RESEND] FMODE_NONOTIFY and FMODE_NEG_OFFSET bits Wu Fengguang
2010-01-30 9:45 ` [PATCH 1/5] fanotify: fix FMODE_NONOTIFY bit number Wu Fengguang
2010-02-01 20:44 ` Andrew Morton
2010-01-30 9:45 ` [PATCH 2/5] bitops: compile time optimization for hweight_long(CONSTANT) Wu Fengguang
2010-02-01 20:48 ` Andrew Morton
2010-02-03 13:39 ` Wu Fengguang
2010-02-03 15:08 ` Andrew Morton
2010-02-03 15:15 ` Peter Zijlstra
2010-02-03 15:42 ` Andrew Morton
2010-02-03 15:47 ` Peter Zijlstra
2010-02-03 17:11 ` H. Peter Anvin
2010-02-03 18:14 ` Borislav Petkov
2010-02-03 18:47 ` Peter Zijlstra
2010-02-03 19:49 ` H. Peter Anvin
2010-02-04 15:10 ` Borislav Petkov
2010-02-04 15:13 ` Peter Zijlstra
2010-02-04 15:54 ` Borislav Petkov
2010-02-04 16:04 ` Peter Zijlstra
2010-02-05 12:11 ` Borislav Petkov
2010-02-05 12:14 ` Peter Zijlstra
2010-02-05 21:54 ` H. Peter Anvin
2010-02-06 9:36 ` Borislav Petkov
2010-02-07 1:55 ` H. Peter Anvin
2010-02-08 9:28 ` Borislav Petkov
2010-02-08 9:35 ` H. Peter Anvin
2010-02-08 9:59 ` Borislav Petkov
2010-02-11 17:24 ` Borislav Petkov
2010-02-11 17:33 ` H. Peter Anvin
2010-02-12 17:06 ` Borislav Petkov
2010-02-12 17:28 ` H. Peter Anvin
2010-02-12 17:47 ` Borislav Petkov
2010-02-12 19:05 ` H. Peter Anvin
2010-02-17 13:57 ` Michal Marek
2010-02-17 17:20 ` Borislav Petkov
2010-02-17 17:31 ` Michal Marek
2010-02-17 17:34 ` Borislav Petkov
2010-02-17 17:39 ` Michal Marek
2010-02-18 6:19 ` Borislav Petkov
2010-02-19 14:22 ` [PATCH] x86: Add optimized popcnt variants Borislav Petkov
2010-02-19 16:06 ` H. Peter Anvin
2010-02-19 16:45 ` Borislav Petkov
2010-02-19 16:53 ` H. Peter Anvin
2010-02-22 14:17 ` Borislav Petkov
2010-02-22 17:21 ` H. Peter Anvin
2010-02-22 18:49 ` Borislav Petkov
2010-02-22 19:55 ` H. Peter Anvin
2010-02-23 6:37 ` Borislav Petkov
2010-02-23 15:58 ` Borislav Petkov
2010-02-23 17:34 ` H. Peter Anvin
2010-02-23 17:54 ` Borislav Petkov [this message]
2010-02-23 18:17 ` H. Peter Anvin
2010-02-23 19:06 ` Borislav Petkov
2010-02-26 5:27 ` H. Peter Anvin
2010-02-26 7:47 ` Borislav Petkov
2010-02-26 17:48 ` H. Peter Anvin
2010-02-27 8:28 ` Borislav Petkov
2010-02-27 20:00 ` H. Peter Anvin
2010-03-09 15:36 ` Borislav Petkov
2010-03-09 15:50 ` Peter Zijlstra
2010-03-09 16:23 ` Borislav Petkov
2010-03-09 16:32 ` Peter Zijlstra
2010-03-09 17:32 ` Borislav Petkov
2010-03-09 17:37 ` Peter Zijlstra
2010-03-18 11:17 ` Borislav Petkov
2010-03-18 11:19 ` [PATCH 1/2] bitops: Optimize hweight() by making use of compile-time evaluation Borislav Petkov
2010-03-18 11:20 ` [PATCH 2/2] x86: Add optimized popcnt variants Borislav Petkov
2010-02-18 10:51 ` [PATCH 2/5] bitops: compile time optimization for hweight_long(CONSTANT) Peter Zijlstra
2010-02-18 11:51 ` Borislav Petkov
2010-02-14 10:12 ` Peter Zijlstra
2010-02-14 11:24 ` Borislav Petkov
2010-02-14 12:23 ` Peter Zijlstra
2010-02-14 14:19 ` Borislav Petkov
2010-02-14 18:36 ` H. Peter Anvin
2010-02-14 20:28 ` Borislav Petkov
2010-02-14 22:13 ` H. Peter Anvin
2010-02-04 15:16 ` H. Peter Anvin
2010-02-04 15:39 ` Brian Gerst
2010-02-03 17:10 ` H. Peter Anvin
2010-01-30 9:45 ` [PATCH 3/5] vfs: O_* bit numbers uniqueness check Wu Fengguang
2010-01-30 9:45 ` [PATCH 4/5] vfs: introduce FMODE_NEG_OFFSET for allowing negative f_pos Wu Fengguang
2010-01-30 9:45 ` [PATCH 5/5] devmem: dont allow seek to last page Wu Fengguang
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=20100223175457.GA2401@aftab \
--to=bp@amd64.org \
--cc=akpm@linux-foundation.org \
--cc=brgerst@gmail.com \
--cc=fengguang.wu@intel.com \
--cc=hpa@zytor.com \
--cc=jamie@shareable.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kbuild@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=mmarek@suse.cz \
--cc=peterz@infradead.org \
--cc=rdreier@cisco.com \
--cc=viro@ZenIV.linux.org.uk \
/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 NNTP newsgroup(s).