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Re: emulating 8086 subset.

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On 11/07/2015 08:51, luser droog wrote:
> On Saturday, June 27, 2015 at 7:02:37 AM UTC-5, somebody wrote:
>>
>> *Lose the macros*.
>
> non-wrapped at:
> https://gist.github.com/luser-dr00g/aef0342cb4a63d682c13

It hasn't really helped! Now there are the pointless typedefs. And (I 
haven't followed the thread) presumably the original macros have been 
expanded, but resulting in a large, unformatted lines or blocks of code.

Isn't there a tool that can take such code and format it properly? (But 
somehow I doubt that will help.)

It's not clear what the aims are here: to make something as fast as 
possible or as compact as possible. It's certainly not readability!

> typedef intptr_t I; typedef uintptr_t U;

Nobody uses I or U. Enough people i32, u32 etc that at least it will not 
look totally alien.

> typedef signed char C; typedef unsigned char UC;

And here 'byte' is better. At least it looks like a type!

> UC*al;UC*ah;UC*cl;UC*ch;UC*dl;UC*dh;UC*bl;UC*bh;US*ax;US*cx;US*dx;US*bx;US*sp;US*bp;US*si;US*di;US*ip;US*fl;US*cs;US*ds;US*ss;US*es;V init(){I i=0;al=(UC*)(reg+i++);ah=(UC*)(reg+i++);cl=(UC*)(reg+i++);ch=(UC*)(reg+i++);dl=(UC*)(reg+i++);dh=(UC*)(reg+i++);bl=(UC*)(reg+i++);bh=(UC*)(reg+i++);i=0;ax=(US*)(reg+i);i+=2;cx=(US*)(reg+i);i+=2;dx=(US*)(reg+i);i+=2;bx=(US*)(reg+i);i+=2;sp=(US*)(reg+i);i+=2;bp=(US*)(reg+i);i+=2;si=(US*)(reg+i);i+=2;di=(US*)(reg+i);i+=2;ip=(US*)(reg+i);i+=2;fl=(US*)(reg+i);i+=2;cs=(US*)(reg+i);i+=2;ds=(US*)(reg+i);i+=2;ss=(US*)(reg+i);i+=2;es=(US*)(reg+i);i+=2;}

Let me guess, a macro expansion? How would you write it if you had to do 
by hand?

My point is that as written, it's not really human readable. I'm not 
sure it even counts calling it C, even if it makes legitimate use of the 
macro preprocessor.

 >ch=(UC*)(reg+i++);dl=(UC*)(reg+i++);dh=(UC*)(reg+i++);bl=(UC*)
 >(reg+i++);bh=(UC*)(reg+i++);i=0;ax=(US*)(reg+i);i+=2;cx=(US*)(reg+i);
 >i+=2;dx=(US*)(reg+i);i+=2;bx=(US*)(reg+i);i+=2;sp=(US*)(reg+i);i+=2;bp=
 >(US*)(reg+i);i+=2;si=(US*)(reg+i);i+=2;di=(US*)(reg+i);i+=2;ip=
 >....

This looks like it's crying out for these register variables to be 
implemented as arrays (which is how it works on the actual chip; 
registers are indexed by 0 to 7). With registers such as AX/AL/AH 
implemented as unions... But then as I said I don't know what the aims are.

-- 
Bartc

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emulating 8086 subset. luser droog <luser.droog@gmail.com> - 2015-06-27 00:34 -0700
  Re: emulating 8086 subset. luser droog <luser.droog@gmail.com> - 2015-06-27 01:18 -0700
  Re: emulating 8086 subset. luser droog <luser.droog@gmail.com> - 2015-06-27 01:28 -0700
    Re: emulating 8086 subset. luser droog <luser.droog@gmail.com> - 2015-06-28 21:21 -0700
    Re: emulating 8086 subset. luser droog <luser.droog@gmail.com> - 2015-06-28 22:50 -0700
      Re: GOLFulating 8086 subset. gensym? luser droog <luser.droog@gmail.com> - 2015-07-01 15:36 -0700
        Re: GOLFulating 8086 subset. gensym? luser droog <luser.droog@gmail.com> - 2015-07-01 16:02 -0700
          Re: GOLFulating 8086 subset. gensym? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-07-01 16:11 -0700
            Re: GOLFulating 8086 subset. gensym? luser droog <luser.droog@gmail.com> - 2015-07-01 16:52 -0700
              Re: GOLFulating 8086 subset. gensym? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-07-01 16:56 -0700
                Re: GOLFulating 8086 subset. gensym? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-07-01 22:12 -0700
  Re: emulating 8086 subset. Ian Collins <ian-news@hotmail.com> - 2015-06-27 21:38 +1200
    Re: emulating 8086 subset. luser droog <luser.droog@gmail.com> - 2015-06-27 02:51 -0700
      Re: emulating 8086 subset. Richard Heathfield <rjh@cpax.org.uk> - 2015-06-27 13:02 +0100
        Re: emulating 8086 subset. Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-06-27 14:25 +0100
        Re: emulating 8086 subset. luser droog <luser.droog@gmail.com> - 2015-07-11 00:51 -0700
          Re: emulating 8086 subset. "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-07-11 01:54 -0700
            Re: emulating 8086 subset. luser droog <luser.droog@gmail.com> - 2015-07-11 01:58 -0700
            Re: emulating 8086 subset. "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-07-11 01:59 -0700
              Re: emulating 8086 subset. luser droog <luser.droog@gmail.com> - 2015-07-11 02:13 -0700
                Re: emulating 8086 subset. "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-07-11 02:34 -0700
                Re: emulating 8086 subset. Bartc <bc@freeuk.com> - 2015-07-11 10:50 +0100
                Re: emulating 8086 subset. "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-07-11 02:58 -0700
                Re: emulating 8086 subset. "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-07-11 02:52 -0700
          Re: emulating 8086 subset. Bartc <bc@freeuk.com> - 2015-07-11 10:38 +0100
            Re: emulating 8086 subset. luser droog <luser.droog@gmail.com> - 2015-07-11 03:16 -0700
              Re: emulating 8086 subset. "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-07-11 03:19 -0700
  emulating 8086 subset. "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-06-27 03:07 -0700
    emulating 8086 subset. "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-06-27 03:58 -0700
  Re: emulating 8086 subset. luser droog <luser.droog@gmail.com> - 2015-07-10 10:51 -0700
  Re: emulating 8086 subset. JohnF <john@please.see.sig.for.email.com> - 2015-07-11 10:07 +0000

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