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    SubjectRe: [PATCH 0/1] vsprintf: optimize decimal conversion (again)
    On 2012.03.28 13:13, Denys Vlasenko wrote:
    > Third: switch to algorithm #1 and test whether it fares better.
    > To do that, go to test_new.c
    > and replace
    > #if LONG_MAX> ((1UL<<31)-1) || LLONG_MAX> ((1ULL<<63)-1)
    > with
    > #if 1 ////LONG_MAX> ((1UL<<31)-1) || LLONG_MAX> ((1ULL<<63)-1)
    > (there are two instances of this line there),
    > then recompile and rerun the test, and post the result.

    After applied following diff:


    --- test_new.org.c 2012-03-28 13:25:14.000000000 +0300
    +++ test_new.c 2012-03-28 13:25:30.000000000 +0300
    @@ -7,7 +7,7 @@
    * (with permission from the author, Douglas W. Jones).
    */

    -#if LONG_MAX > ((1UL<<31)-1) || LLONG_MAX > ((1ULL<<63)-1)
    +#if 1 ////LONG_MAX > ((1UL<<31)-1) || LLONG_MAX > ((1ULL<<63)-1)
    /* Formats correctly any integer in [0, 999999999] */
    static noinline_for_stack
    char *put_dec_full9(char *buf, unsigned q)
    @@ -106,7 +106,7 @@
    * Else (if long is 32 bits and long long is 64 bits) we use second one.
    */

    -#if LONG_MAX > ((1UL<<31)-1) || LLONG_MAX > ((1ULL<<63)-1)
    +#if 1 ///LONG_MAX > ((1UL<<31)-1) || LLONG_MAX > ((1ULL<<63)-1)

    /* First algorithm: generic */

    I have following compile output:
    $ arm-linux-gnueabi-gcc -O2 -Wall test_new.c -o test_new
    test_new.c: In function ‘number’:
    test_new.c:118: error: impossible constraint in ‘asm’
    test_new.c:118: error: impossible constraint in ‘asm’
    test_new.c:118: error: impossible constraint in ‘asm’

    but affter this diff:
    --- test_new-with-ifdefs.c 2012-03-28 13:29:04.000000000 +0300
    +++ test_new.c 2012-03-28 13:29:12.000000000 +0300
    @@ -1,4 +1,4 @@
    -#include "test_header.c"
    +#include "test_header_arm.c"

    /* Decimal conversion is by far the most typical, and is used
    * for /proc and /sys data. This directly impacts e.g. top performance
    compiles fine.

    result are:
    ./test_new2
    Conversions per second: 8:5420000 123:4452000 123456:3556000 12345678:3368000
    123456789:2904000 2^32:2412000 2^64:1556000
    Conversions per second: 8:5428000 123:4500000 123456:3644000 12345678:3328000
    123456789:2832000 2^32:2408000 2^64:1572000
    Conversions per second: 8:5372000 123:4396000 123456:3644000 12345678:3368000
    123456789:2900000 2^32:2392000 2^64:1532000
    Conversions per second: 8:5424000 123:4500000 123456:3608000 12345678:3284000
    123456789:2896000 2^32:2416000 2^64:1572000
    btw: previovios version (test_new) still running, now is at:
    Tested 2446852096

    roma1390

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