linux-kernel - Re: [PATCH 0/1] vsprintf: optimize decimal conversion (again)

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Message-Id: <201203281233.42914.vda.linux@googlemail.com>
Date:	Wed, 28 Mar 2012 12:33:42 +0200
From:	Denys Vlasenko <vda.linux@...glemail.com>
To:	roma1390 <roma1390@...il.com>
Cc:	linux-kernel@...r.kernel.org,
	Andrew Morton <akpm@...ux-foundation.org>,
	Douglas W Jones <jones@...uiowa.edu>,
	Michal Nazarewicz <mnazarewicz@...gle.com>
Subject: Re: [PATCH 0/1] vsprintf: optimize decimal conversion (again)

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?

-- 
vda
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