From: Denys Vlasenko <vda.linux@googlemail.com>
To: roma1390 <roma1390@gmail.com>
Cc: linux-kernel@vger.kernel.org,
Andrew Morton <akpm@linux-foundation.org>,
Douglas W Jones <jones@cs.uiowa.edu>,
Michal Nazarewicz <mnazarewicz@google.com>
Subject: Re: [PATCH 0/1] vsprintf: optimize decimal conversion (again)
Date: Wed, 28 Mar 2012 13:20:07 +0200 [thread overview]
Message-ID: <201203281320.07765.vda.linux@googlemail.com> (raw)
In-Reply-To: <4F72EA68.9090605@gmail.com>
On Wednesday 28 March 2012 12:39, roma1390 wrote:
> On 2012.03.28 13:33, Denys Vlasenko wrote:
> > On Wednesday 28 March 2012 12:24, roma1390 wrote:
> >> On 2012.03.28 13:13, Denys Vlasenko wrote:
> >>> Second: run
> >>> arm-linux-gnueabi-gcc -O2 -Wall test_{org,new}.c -S
> >>> and email me resulting test_{org,new}.s files.
> >>
> >> test_{org,new}.s attached.
> >
> >
> > Bingo.
> >
> > bl __aeabi_uidivmod
> >
> > Not good. Your gcc did not optimize division by constant.
> >
> > Can you add "noinline_for_stack":
> >
> > static noinline_for_stack<=== HERE
> > char *put_dec(char *buf, unsigned long long n)
> >
> > amd regenerate and resend the test_new.s?
> >
>
> Hello,
>
> Your requested asm are attached.
Asm looks good: there are only three long multiplies in the
put_dec + put_dec_full4, and no divisions at all.
Please speed-test this version.
--
vda
next prev parent reply other threads:[~2012-03-28 11:20 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-03-26 18:47 [PATCH 0/1] vsprintf: optimize decimal conversion (again) Denys Vlasenko
2012-03-26 18:51 ` [PATCH 1/1] " Denys Vlasenko
2012-03-26 19:51 ` Andrew Morton
2012-03-26 19:56 ` Denys Vlasenko
2012-03-26 20:13 ` Andrew Morton
2012-03-26 20:18 ` Geert Uytterhoeven
2012-03-26 23:18 ` Denys Vlasenko
2012-03-27 0:30 ` Denys Vlasenko
2012-03-27 3:49 ` H. Peter Anvin
2012-03-26 20:20 ` H. Peter Anvin
2012-03-27 17:12 ` Michal Nazarewicz
2012-03-27 17:17 ` H. Peter Anvin
2012-03-27 0:26 ` Denys Vlasenko
2012-03-27 12:08 ` [PATCH 0/1] " roma1390
2012-03-27 15:32 ` Denys Vlasenko
2012-03-27 15:42 ` Denys Vlasenko
2012-03-28 5:56 ` roma1390
2012-03-28 10:13 ` Denys Vlasenko
2012-03-28 10:24 ` roma1390
2012-03-28 10:33 ` Denys Vlasenko
2012-03-28 10:39 ` roma1390
2012-03-28 11:20 ` Denys Vlasenko [this message]
2012-03-29 10:35 ` Denys Vlasenko
2012-03-28 10:31 ` roma1390
2012-03-28 11:23 ` Denys Vlasenko
2012-03-29 5:23 ` roma1390
2012-03-29 10:33 ` Denys Vlasenko
2012-03-27 13:49 ` roma1390
2012-03-27 15:33 ` Denys Vlasenko
2012-03-29 5:16 ` roma1390
2012-03-29 10:33 ` Denys Vlasenko
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