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

From: Denys Vlasenko
Date: Wed Mar 28 2012 - 06:33:47 EST


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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