[M3commit] [M3devel] m3back using Target.Int in place of INTEGER a lot now

[Jay K]

I'll look into it again.
There's definitely a problem somewhere.
 Maybe in my change. Maybe.
 
 
Using TInt.Multiply vs. TWord.Multiply made the difference
between INC() incrementing by zero or the correct amount.
I had some number, I multiplied it by a variable
that also happened to be 1, and I got zero.
This was the only problem I ran into in changing
from INTEGER to Target.Int.
 
 
 - Jay

________________________________
> From: hosking at cs.purdue.edu
> Date: Wed, 20 Jan 2010 20:00:39 -0500
> To: hosking at cs.purdue.edu
> CC: m3devel at elegosoft.com; m3commit at elegosoft.com; jay.krell at cornell.edu
> Subject: Re: [M3devel] [M3commit] m3back using Target.Int in place of INTEGER a lot now
>
>
>
>
> Jay, I don't know what you are talking about there being a bug in TWord.Multiply.
>
> This little program prints out 2, as would be expected:
>
> MODULE Main;
> IMPORT RTIO, TInt, TWord, Target;
>
> VAR i := TInt.Two;
> j: Target.Int;
> buf: ARRAY[0..10] OF CHAR;
> BEGIN
> TWord.Multiply (i, TInt.One, j);
> FOR k := 0 TO TInt.ToChars (i, buf) DO
> RTIO.PutChar(buf[k]);
> END;
> RTIO.PutChar('\n');
> RTIO.Flush();
> END Main.
>
>
> On 20 Jan 2010, at 18:59, Tony Hosking wrote:
>
> Where's the bug in TWord.Multiply?
> If there were a bug we would have seen it by now surely?
>
>
> Antony Hosking | Associate Professor | Computer Science | Purdue University
> 305 N. University Street | West Lafayette | IN 47907 | USA
> Office +1 765 494 6001 | Mobile +1 765 427 5484
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>
> On 20 Jan 2010, at 10:05, Jay K wrote:
>
> This is fairly large and tedious. If anyone has the patience to look at every single line, please do. Thanks.
> I did look through pretty much every single line in search of the one bug I saw working on it.
> It turns out the bug was in TWord though. TWord.Multiply(x, 1) = 0.
> Which broke INC, it was adding 0 instead 1.
> You could see the bug in RTIO.PutString where it just kept outputing the first character.
> So I use TInt.Multiply instead.
>
> - Jay
>
> ________________________________
> From: jay.krell at cornell.edu
> To: jkrell at elego.de; m3commit at elegosoft.com
> Date: Wed, 20 Jan 2010 15:02:27 +0000
> Subject: Re: [M3commit] CVS Update: cm3
>
> diff attached
>
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>
>> Date: Wed, 20 Jan 2010 16:01:32 +0000
>> To: m3commit at elegosoft.com
>> From: jkrell at elego.de
>> Subject: [M3commit] CVS Update: cm3
>>
>> CVSROOT: /usr/cvs
>> Changes by: jkrell at birch. 10/01/20 16:01:32
>>
>> Modified files:
>> cm3/m3-sys/m3back/src/: Codex86.i3 Codex86.m3 M3x86.m3
>> M3x86Rep.i3 Stackx86.i3 Stackx86.m3
>> cm3/m3-sys/m3middle/src/: TInt.i3 TInt.m3
>>
>> Log message:
>> convert much of m3back to use Target.Int instead of INTEGER
>> This should at least allow it to propagate constant LONGINTs
>> as well as perhaps otherwise help with implementing LONGINT,
>> since the virtual stack is now of Target.Int instead of INTEGER
>>
>> Beware that TWord.Multiply(x, 1) = 0, so I use TInt.Multiply instead
>>
>> Also note that there's still a lot of "INTEGER" used.
>>
>
>