Re: on an analogy for verifying whether another digit fits (into an unsigned type)

From	Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups	comp.lang.c
Subject	Re: on an analogy for verifying whether another digit fits (into an unsigned type)
Date	2022-01-20 03:49 +0000
Organization	A noiseless patient Spider
Message-ID	<87tudz2his.fsf@bsb.me.uk> (permalink)
References	(5 earlier) <ss9l6b$ctv$1@dont-email.me> <C0ZFJ.134459$Gco3.62864@fx01.iad> <ss9u3b$jdr$1@dont-email.me> <X8%FJ.28$rU.26@fx34.iad> <ssa342$rih$1@dont-email.me>

Show all headers | View raw

Bart <bc@freeuk.com> writes:

> But in the case of strtoull, there are other issues with it:
>
> * Not all compilers may recognise it

It's almost always library issue, not a compiler issue.  Any
implementation (compiler + library) that does not have it is a poor one
since it's been standard for a long time now.

> * The performance depends on the library used
>
> Using your own routine for this simple task eliminates those variables.
>
> The timing I quoted was the worst:
>
> * gcc/strtoull on Windows: 2.8 seconds (for 1M conversions)
>
> * gcc/strtoull on WSL: 0.6 seconds
>
> * gcc/_strtoui64 on Windows (in msvcrt): 0.7 seconds

You keep citing figures with little useful information.  What length
numbers?  What are these various (apparently slow) implementation of
strtoull that you have managed to find?  Calling them gcc/strtoull is
not helpful.

For 10^6 numbers with, on average, 18.3 digits, the strtoull on a recent
Ubuntu install (glibc 2.34) does the conversions in 0.042 seconds
(i5-8265U CPU).  Is your machine really more than 10 times slower than
my laptop?

> * My parseull routine on Windows: 0.28/0.35 seconds (with/without
> length)

This one probably doesn't do the same job, so it's not a direct
comparison.

-- 
Ben.

Thread

on an analogy for verifying whether another digit fits (into an unsigned type) Meredith Montgomery <mmontgomery@levado.to> - 2022-01-15 23:27 -0300
  Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bart <bc@freeuk.com> - 2022-01-16 18:44 +0000
    Re: on an analogy for verifying whether another digit fits (into an unsigned type) Meredith Montgomery <mmontgomery@levado.to> - 2022-01-17 09:48 -0300
      Re: on an analogy for verifying whether another digit fits (into an unsigned type) Ben Bacarisse <ben.usenet@bsb.me.uk> - 2022-01-17 17:27 +0000
        Re: on an analogy for verifying whether another digit fits (into an unsigned type) scott@slp53.sl.home (Scott Lurndal) - 2022-01-17 18:06 +0000
          Re: on an analogy for verifying whether another digit fits (into an unsigned type) Ben Bacarisse <ben.usenet@bsb.me.uk> - 2022-01-17 20:59 +0000
            Re: on an analogy for verifying whether another digit fits (into an unsigned type) scott@slp53.sl.home (Scott Lurndal) - 2022-01-18 01:01 +0000
        Re: on an analogy for verifying whether another digit fits (into an unsigned type) Meredith Montgomery <mmontgomery@levado.to> - 2022-01-28 22:15 -0300
          Re: on an analogy for verifying whether another digit fits (into an unsigned type) Ben Bacarisse <ben.usenet@bsb.me.uk> - 2022-01-29 02:36 +0000
            Re: on an analogy for verifying whether another digit fits (into an unsigned type) Meredith Montgomery <mmontgomery@levado.to> - 2022-01-30 09:12 -0300
              Re: on an analogy for verifying whether another digit fits (into an unsigned type) Ben Bacarisse <ben.usenet@bsb.me.uk> - 2022-01-30 15:13 +0000
  Re: on an analogy for verifying whether another digit fits (into an unsigned type) Öö Tiib <ootiib@hot.ee> - 2022-01-16 12:15 -0800
    Re: on an analogy for verifying whether another digit fits (into an unsigned type) Meredith Montgomery <mmontgomery@levado.to> - 2022-01-17 09:53 -0300
      Re: on an analogy for verifying whether another digit fits (into an unsigned type) Meredith Montgomery <mmontgomery@levado.to> - 2022-01-17 10:12 -0300
  Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bonita Montero <Bonita.Montero@gmail.com> - 2022-01-19 08:52 +0100
    Re: on an analogy for verifying whether another digit fits (into an unsigned type) Öö Tiib <ootiib@hot.ee> - 2022-01-19 06:08 -0800
      Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bonita Montero <Bonita.Montero@gmail.com> - 2022-01-19 16:31 +0100
        Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bonita Montero <Bonita.Montero@gmail.com> - 2022-01-19 18:02 +0100
          Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bart <bc@freeuk.com> - 2022-01-19 18:27 +0000
            Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bonita Montero <Bonita.Montero@gmail.com> - 2022-01-19 19:44 +0100
              Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bonita Montero <Bonita.Montero@gmail.com> - 2022-01-20 08:08 +0100
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Öö Tiib <ootiib@hot.ee> - 2022-01-20 09:47 -0800
            Re: on an analogy for verifying whether another digit fits (into an unsigned type) scott@slp53.sl.home (Scott Lurndal) - 2022-01-19 18:46 +0000
              Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bart <bc@freeuk.com> - 2022-01-19 20:59 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) scott@slp53.sl.home (Scott Lurndal) - 2022-01-19 21:12 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bart <bc@freeuk.com> - 2022-01-19 22:25 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Ben Bacarisse <ben.usenet@bsb.me.uk> - 2022-01-20 03:49 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bart <bc@freeuk.com> - 2022-01-20 10:05 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Ben Bacarisse <ben.usenet@bsb.me.uk> - 2022-01-20 17:02 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bart <bc@freeuk.com> - 2022-01-20 19:20 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bart <bc@freeuk.com> - 2022-01-20 19:31 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2022-01-23 14:26 -0800
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bart <bc@freeuk.com> - 2022-01-24 00:13 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2022-01-24 00:38 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bart <bc@freeuk.com> - 2022-01-24 01:09 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Ben Bacarisse <ben.usenet@bsb.me.uk> - 2022-01-24 01:15 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bart <bc@freeuk.com> - 2022-01-24 11:21 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) scott@slp53.sl.home (Scott Lurndal) - 2022-01-24 15:54 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2022-01-24 13:08 -0800
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) scott@slp53.sl.home (Scott Lurndal) - 2022-01-24 22:51 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Ben Bacarisse <ben.usenet@bsb.me.uk> - 2022-01-24 15:57 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bart <bc@freeuk.com> - 2022-01-24 16:52 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Öö Tiib <ootiib@hot.ee> - 2022-01-24 10:17 -0800
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) scott@slp53.sl.home (Scott Lurndal) - 2022-01-24 18:23 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2022-01-24 13:15 -0800
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bart <bc@freeuk.com> - 2022-01-24 11:51 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2022-01-23 17:38 -0800
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bart <bc@freeuk.com> - 2022-01-24 11:22 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) scott@slp53.sl.home (Scott Lurndal) - 2022-01-24 15:51 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bart <bc@freeuk.com> - 2022-01-24 22:03 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2022-01-24 15:33 -0800
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bart <bc@freeuk.com> - 2022-01-25 00:09 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2022-01-24 21:14 -0800
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Manfred <invalid@invalid.add> - 2022-01-26 21:01 +0100
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bart <bc@freeuk.com> - 2022-01-26 20:53 +0000
                Re: on an analogy for verifying whether another digit fits (into an unsigned type) Manfred <noname@add.invalid> - 2022-01-27 03:42 +0100
  Re: on an analogy for verifying whether another digit fits (into an unsigned type) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2022-01-20 19:24 -0800
    Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bonita Montero <Bonita.Montero@gmail.com> - 2022-01-21 08:07 +0100
      Re: on an analogy for verifying whether another digit fits (into an unsigned type) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2022-01-21 06:01 -0800
        Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bonita Montero <Bonita.Montero@gmail.com> - 2022-01-21 17:59 +0100
          Re: on an analogy for verifying whether another digit fits (into an unsigned type) scott@slp53.sl.home (Scott Lurndal) - 2022-01-21 17:41 +0000
            Re: on an analogy for verifying whether another digit fits (into an unsigned type) Bonita Montero <Bonita.Montero@gmail.com> - 2022-01-21 19:26 +0100
          Re: on an analogy for verifying whether another digit fits (into an unsigned type) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2022-01-21 17:12 -0800
    Re: on an analogy for verifying whether another digit fits (into an unsigned type) Meredith Montgomery <mmontgomery@levado.to> - 2022-01-28 22:25 -0300

csiph-web