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    SubjectRe: [PATCH 0/1] vsprintf: optimize decimal conversion (again)
    On Wed, Mar 28, 2012 at 12:33 PM, Denys Vlasenko
    <vda.linux@googlemail.com> 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)
    >
    > and regenerate and resend the test_new.s?

    Since you confirmed that noinlining helps,
    I recommend you to file a gcc bug report:
    your gcc misses an optimization when it inlines
    that function.

    --
    vda
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