Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail
From: bart <bc@freeuk.com>
Newsgroups: comp.lang.c
Subject: Re: C23 thoughts and opinions
Date: Sun, 26 May 2024 22:52:25 +0100
Organization: A noiseless patient Spider
Lines: 97
Message-ID: <v30auq$3kcu9$1@dont-email.me>
References: <v2l828$18v7f$1@dont-email.me>
 <00297443-2fee-48d4-81a0-9ff6ae6481e4@gmail.com>
 <v2lji1$1bbcp$1@dont-email.me> <87msoh5uh6.fsf@nosuchdomain.example.com>
 <f08d2c9f-5c2e-495d-b0bd-3f71bd301432@gmail.com>
 <v2nbp4$1o9h6$1@dont-email.me> <v2ng4n$1p3o2$1@dont-email.me>
 <87y18047jk.fsf@nosuchdomain.example.com>
 <87msoe1xxo.fsf@nosuchdomain.example.com> <v2sh19$2rle2$2@dont-email.me>
 <87ikz11osy.fsf@nosuchdomain.example.com> <v2v59g$3cr0f$1@dont-email.me>
 <v2v7ni$3d70v$1@dont-email.me> <20240526161832.000012a6@yahoo.com>
 <v2vka0$3f4a2$1@dont-email.me> <20240526193549.000031a8@yahoo.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Injection-Date: Sun, 26 May 2024 23:52:26 +0200 (CEST)
Injection-Info: dont-email.me; posting-host="8e9185d4e0820a2f5b79db78e2103a30";
	logging-data="3814345"; mail-complaints-to="abuse@eternal-september.org";	posting-account="U2FsdGVkX19csqQULMECvgR9jQ6+EoHN"
User-Agent: Mozilla Thunderbird
Cancel-Lock: sha1:PhzqxP/v7x1vZMpx3QHIZWl/ptk=
In-Reply-To: <20240526193549.000031a8@yahoo.com>
Content-Language: en-GB
Bytes: 4187

On 26/05/2024 17:35, Michael S wrote:

> #include <stdio.h>
> #include <stdlib.h>
> #include <ctype.h>
> 
> int main(int argz, char** argv)
> {
>    if (argz > 1) {
>      FILE* fp = fopen(argv[1], "wb");
>      if (fp) {
>        char buf[2048];
>        _Bool look_for_comma = 0;
>        for (;;) {
>          if (fgets(buf, sizeof(buf), stdin) != buf)
>            break;
> 
>          char* p = buf;
>          for (;;) {
>            char c = *p;
>            if (isgraph(c)) {
>              if (look_for_comma) {
>                if (c == ',') {
>                  look_for_comma = 0;
>                  ++p;
>                } else {
>                  goto done;
>                }
>              } else {
>                char* endp;
>                long val = strtol(p, &endp, 0);
>                if (endp==p) // not a number
>                  goto done;
>                fputc((unsigned char)val, fp);
>                p = endp;
>                look_for_comma = 1;
>              }
>            } else {
>              if (c == 0)
>                break; // end of line
>              ++p; // skip space or control character
>            }
>          }
>        }
>        done:
>        fclose(fp);
>      } else {
>        perror(argv[1]);
>        return 1;
>      }
>    }
>    return 0;
> }

I tried this on my 600MB data like this:

   C:\c>c fred.exe <data

   C:\c>fred --version
   clang version 18.1.0rc
   Target: x86_64-pc-windows-msvc
   Thread model: posix
   InstalledDir: C:\c

Since those bytes represent the contents of the clang compiler, I was 
able to run it afterwards.

All versions across compilers/optimise levels seemed to give a constant 
time of 17-18 seconds. This is good compared with my initial 144 seconds 
(most compilers failed; you reported a similar test took several minutes).

However, what's involved with a compiler is much elaborate than such a 
program. There's syntax, type-checking, code-generation...

Still, I reported earlier an experimental change to my non-C compiler, 
which translated this same input to a program with that embedded binary 
(not just the binary itself) in under 6 seconds.

That's three times as fast as the above result:

   C:\mapps>tm \mx2\mm -ext test2          # tm is  timing tool
   Compiling test2.m to test2.exe
   TM: 5.86                                # (timings vary)

   C:\mapps>test2
   data is 119571969 bytes

   C:\mapps>type test2.m
    []byte data = (
        include "data"
    0)

    proc main=
        fprintln "data is # bytes", data.len
    end