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Groups > comp.lang.c > #140013
| Subject | Re: Compiler tests |
|---|---|
| Newsgroups | comp.lang.c |
| References | <%UO0E.109606$Ur2.51894@fx14.am4> <gai9j2Fuek4U6@mid.individual.net> <m24la3llvv.fsf@despina.home> <q21mhu$jm6$1@dont-email.me> |
| From | Bart <bc@freeuk.com> |
| Message-ID | <lp_0E.182687$1D1.4718@fx29.am4> (permalink) |
| Organization | virginmedia.com |
| Date | 2019-01-20 13:08 +0000 |
On 20/01/2019 11:37, David Brown wrote:
> On 20/01/2019 10:27, Pascal J. Bourguignon wrote:
>> Well, obviously some compilers try to optimize duplicate expressions,
>> and get lost in the number of them. Not a realistic test, but
>> definitely a good try-to-break-the-compiler test.
>>
>
> Unfortunately for Bart, compilers are usually targeted to real code. And
> in real code, duplicate expressions and structures /do/ turn up
> (especially in template-based C++ coding), and optimising them is very
> important to the efficiency of the code generation.
Except that the problem timings were with /unoptimised/ compiles. With
optimisation enabled, they were much faster.
But meaningless
> mass copying of the same code does not turn up in real code, and
> compiler writers don't particularly care about the results.
>
> This means that Bart's simplistic compiler can do a better job than real
> compilers at this kind of meaningless artificial benchmark, and he likes
> to trump it as "proof" that his tool is great and gcc is terrible. It's
> a common theme for him, and it is no more useful now than it was the
> past dozen times he presented this.
>
>
> There /are/ issues with gcc compiling very large functions (in
> particular, it takes a huge amount of memory), there are real use-cases
> (such as for simulators), and there is work being done to improve
> things. I don't know the current state.
Here's another test where each line is in a separate function:
void f1(void) {int a,b=2,c=3,d=4; a=b+c*d;}
void f2(void) {int a,b=2,c=3,d=4; a=b+c*d;}
void f3(void) {int a,b=2,c=3,d=4; a=b+c*d;}
void f4(void) {int a,b=2,c=3,d=4; a=b+c*d;}
....
And here are some quick results:
20K 100K
Pelles C T/O ---
lccwin 13.0 T/O seconds to compile
dmc 0.4 OOM
gcc 25.0 307.0
gcc opt 39.0 ---
tiny c 0.2 0.7
msvc 3.0 34.0
clang 6.3 30.0
(bcc 0.3 1.6)
They still seem to fare very differently.
This test was useful in that it highlighted a problem with my bcc, which
suffers from using a fixed-size hashtable for the main symbol table. The
1.6 figure is after tweaking the size. I will to change it to adapt as
needed.
However, bcc generates .asm, and my assembler for that has its own hard
limit of 64K entries that can't be so easily changed, but it will have
to in order to create an exe from this.
Why does gcc's speed get slower non-linearly compared with clang? Maybe
it could also have issues that need looking at. It seemed to spend an
awfully long time running 'as'.
(I would like to see one of your test-suites where every single test
program is useful real-life code.)
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Compiler tests Bart <bc@freeuk.com> - 2019-01-20 00:03 +0000
Re: Compiler tests Ian Collins <ian-news@hotmail.com> - 2019-01-20 16:52 +1300
Re: Compiler tests "Pascal J. Bourguignon" <pjb@informatimago.com> - 2019-01-20 10:27 +0100
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-20 12:37 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-20 13:08 +0000
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-20 15:02 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-20 17:31 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-20 17:08 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-20 21:40 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-20 22:41 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-21 00:39 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-21 00:36 +0000
Re: Compiler tests Ian Collins <ian-news@hotmail.com> - 2019-01-21 16:33 +1300
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-21 11:58 +0000
Re: Compiler tests Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2019-01-21 04:15 -0800
Re: Compiler tests Ian Collins <ian-news@hotmail.com> - 2019-01-22 07:53 +1300
Re: Compiler tests BGB <cr88192@hotmail.com> - 2019-01-23 01:15 -0600
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-23 12:00 +0000
Re: Compiler tests Ian Collins <ian-news@hotmail.com> - 2019-01-24 08:13 +1300
Re: Compiler tests BGB <cr88192@hotmail.com> - 2019-01-23 13:30 -0600
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-21 08:22 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-21 12:23 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-21 14:42 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-21 14:17 +0000
Re: Compiler tests Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2019-01-21 12:46 -0800
You guys really, really need to get a room (Was: Compiler tests) gazelle@shell.xmission.com (Kenny McCormack) - 2019-01-24 14:05 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-20 17:27 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-20 17:19 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-21 09:44 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-21 12:49 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-21 15:31 +0100
Re: Compiler tests jacobnavia <jacob@jacob.remcomp.fr> - 2019-01-21 14:38 +0100
Re: Compiler tests "Pascal J. Bourguignon" <pjb@informatimago.com> - 2019-01-21 15:15 +0100
Re: Compiler tests jacobnavia <jacob@jacob.remcomp.fr> - 2019-01-21 16:05 +0100
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-21 16:39 +0100
Re: Compiler tests Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2019-01-21 12:51 -0800
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-22 00:16 +0000
Re: Compiler tests jacobnavia <jacob@jacob.remcomp.fr> - 2019-01-22 08:43 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-22 12:31 +0000
Re: Compiler tests jacobnavia <jacob@jacob.remcomp.fr> - 2019-01-22 17:49 +0100
Re: Compiler tests jacobnavia <jacob@jacob.remcomp.fr> - 2019-01-23 11:04 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-23 11:18 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-21 15:35 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-21 15:49 +0000
Re: Compiler tests "Pascal J. Bourguignon" <pjb@informatimago.com> - 2019-01-21 17:42 +0100
Re: Compiler tests BGB <cr88192@hotmail.com> - 2019-01-23 03:18 -0600
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-23 11:11 +0100
Re: Compiler tests BGB <cr88192@hotmail.com> - 2019-01-23 12:18 -0600
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-23 13:56 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-22 10:55 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-22 12:07 +0000
Re: Compiler tests fir <profesor.fir@gmail.com> - 2019-01-22 04:29 -0800
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-22 12:52 +0000
Re: Compiler tests mark.bluemel@gmail.com - 2019-01-22 05:04 -0800
Re: Compiler tests fir <profesor.fir@gmail.com> - 2019-01-22 05:18 -0800
Re: Compiler tests fir <profesor.fir@gmail.com> - 2019-01-22 05:45 -0800
Re: Compiler tests fir <profesor.fir@gmail.com> - 2019-01-22 05:35 -0800
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-22 15:10 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-22 17:30 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-22 23:02 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-22 23:14 +0000
Re: Compiler tests Keith Thompson <kst-u@mib.org> - 2019-01-22 15:45 -0800
Re: Compiler tests Robert Wessel <robertwessel2@yahoo.com> - 2019-01-22 17:57 -0600
Re: Compiler tests Keith Thompson <kst-u@mib.org> - 2019-01-22 16:36 -0800
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-23 01:37 +0000
Re: Compiler tests Keith Thompson <kst-u@mib.org> - 2019-01-22 18:53 -0800
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-23 09:42 +0100
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-23 09:22 +0100
Re: Compiler tests James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-01-23 08:52 -0500
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-23 15:13 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-23 14:33 +0000
Re: Compiler tests James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-01-23 07:30 -0800
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-23 16:05 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-23 17:17 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-23 16:29 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-23 22:04 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-23 21:50 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-24 10:45 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-24 11:55 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-24 13:58 +0100
Re: Compiler tests mark.bluemel@gmail.com - 2019-01-24 05:07 -0800
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-24 14:10 +0000
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-24 14:18 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-24 15:51 +0100
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-24 15:44 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-24 17:32 +0000
Re: Compiler tests scott@slp53.sl.home (Scott Lurndal) - 2019-01-24 19:07 +0000
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-24 20:14 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-24 22:24 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-24 22:46 +0000
Re: Compiler tests Ian Collins <ian-news@hotmail.com> - 2019-01-25 12:34 +1300
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-25 01:01 +0000
Re: Compiler tests Ian Collins <ian-news@hotmail.com> - 2019-01-25 14:15 +1300
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-25 10:05 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-25 14:51 +0000
Re: Compiler tests Mateusz Viste <mateusz@wont.tell> - 2019-01-25 09:48 +0000
Re: Compiler tests "Pascal J. Bourguignon" <pjb@informatimago.com> - 2019-01-25 10:56 +0100
Re: Compiler tests Mateusz Viste <mateusz@wont.tell> - 2019-01-25 12:08 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-25 13:28 +0100
Re: Compiler tests Mateusz Viste <mateusz@wont.tell> - 2019-01-25 13:33 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-25 15:38 +0100
Re: Compiler tests Mateusz Viste <mateusz@wont.tell> - 2019-01-25 15:08 +0000
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-25 13:53 +0000
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-25 12:25 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-25 10:03 +0100
Re: Compiler tests "Pascal J. Bourguignon" <pjb@informatimago.com> - 2019-01-25 10:08 +0100
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-25 11:14 +0100
Re: Compiler tests "Pascal J. Bourguignon" <pjb@informatimago.com> - 2019-01-25 12:02 +0100
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-25 13:37 +0100
Re: Compiler tests "Pascal J. Bourguignon" <pjb@informatimago.com> - 2019-01-25 13:58 +0100
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-25 14:26 +0100
Re: Compiler tests "Pascal J. Bourguignon" <pjb@informatimago.com> - 2019-01-25 15:01 +0100
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-25 15:42 +0100
Re: Compiler tests Keith Thompson <kst-u@mib.org> - 2019-01-25 10:25 -0800
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-25 14:37 +0000
Re: Compiler tests "Pascal J. Bourguignon" <pjb@informatimago.com> - 2019-01-25 16:33 +0100
Re: Compiler tests Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2019-01-25 07:44 -0800
Re: Compiler tests "Pascal J. Bourguignon" <pjb@informatimago.com> - 2019-01-25 17:53 +0100
Re: Compiler tests Keith Thompson <kst-u@mib.org> - 2019-01-25 10:33 -0800
Re: Compiler tests "Pascal J. Bourguignon" <pjb@informatimago.com> - 2019-01-25 20:43 +0100
Re: Compiler tests Keith Thompson <kst-u@mib.org> - 2019-01-25 12:17 -0800
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-25 18:31 +0000
Re: Compiler tests "Pascal J. Bourguignon" <pjb@informatimago.com> - 2019-01-25 20:41 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-25 21:19 +0000
Re: Compiler tests Ian Collins <ian-news@hotmail.com> - 2019-01-26 10:24 +1300
Re: Compiler tests "Pascal J. Bourguignon" <pjb@informatimago.com> - 2019-01-25 22:27 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-25 22:39 +0000
Re: Compiler tests Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-01-25 18:46 +0000
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-25 12:43 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-25 14:37 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-25 14:19 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-25 15:47 +0100
Re: Compiler tests Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2019-01-25 07:17 -0800
Re: Compiler tests Jorgen Grahn <grahn+nntp@snipabacken.se> - 2019-02-03 07:28 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-02-03 12:35 +0100
Re: Compiler tests Jorgen Grahn <grahn+nntp@snipabacken.se> - 2019-02-03 21:47 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-02-03 22:57 +0100
Re: Compiler tests Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2019-01-24 06:47 -0800
Re: Compiler tests Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-01-23 20:22 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-23 22:12 +0100
Re: Compiler tests Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-01-23 21:54 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-24 11:41 +0100
Re: Compiler tests Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-01-24 23:17 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-25 11:11 +0100
Re: Compiler tests Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-01-25 12:04 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-25 14:05 +0100
Re: Compiler tests Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-01-25 18:40 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-25 22:36 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-25 22:15 +0000
Re: Compiler tests scott@slp53.sl.home (Scott Lurndal) - 2019-01-25 14:48 +0000
Re: Compiler tests scott@slp53.sl.home (Scott Lurndal) - 2019-01-25 14:46 +0000
Re: Compiler tests Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-01-25 17:48 +0000
Re: Compiler tests James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-01-23 08:23 -0800
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-23 16:41 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-23 16:18 +0000
Re: Compiler tests David Brown <david.brown@hesbynett.no> - 2019-01-23 17:28 +0100
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-23 20:23 +0000
Re: Compiler tests Robert Wessel <robertwessel2@yahoo.com> - 2019-01-22 17:52 -0600
Re: Compiler tests Bart <bc@freeuk.com> - 2019-01-20 20:17 +0000
Re: Compiler tests BGB <cr88192@hotmail.com> - 2019-01-21 00:13 -0600
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