Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!think.com!sdd.hp.com!hplabs!hpl-opus!hpnmdla!darrylo
From: darrylo@hpnmdla.sr.hp.com (Darryl Okahata)
Newsgroups: comp.sys.handhelds
Subject: Re: Chipper source & stuff
Message-ID: <1570032@hpnmdla.sr.hp.com>
Date: 7 Jun 91 03:57:29 GMT
References: <1991Jun6.145732.14924@ugle.unit.no>
Organization: HP Network Measurements Div, Santa Rosa, CA
Lines: 93

In comp.sys.handhelds, egeberg@solan.unit.no (Christian Egeberg) writes:

> Even though I thought I was through with Chip, I suspect
> I will give in, and port it to Kernighan-Richie style C.
> New mnemonics will be included, and propably conditional
> assembly. The program will be tested on some Sun workstation,
> SCO 386 Unix, and Microsoft C for MS-DOS.

     Why don't you run Chipper through Dave Gillespie's excellent p2c
program (a Unix-based Pascal-to-C translator)?  It won't be perfect, but
it'll be a starting point.  Just as a test, I ran Chipper though p2c,
and it took all of nine seconds.  There's a fair amount of work that
needs to be done before it can be functional (mainly dealing with
FExpand(), FSplit(), and assign()), but it's much easier than
hand-translating the code.

     Here's an example of the translated code.  Before:

-------------------------------------------------------------------------------
PROCEDURE EncodeDwToken( Instruct: InstPointer; Reg, Symb:
SymbolPointer);

VAR
  Param: ParamPointer;
  Value: LongInt;
  This: Byte;

BEGIN
  This:= 0;
  Value:= 0;
  WITH Instruct^ DO
    BEGIN
      Param:= Params;
      WHILE Param <> NIL DO
        BEGIN
          IF NOT ResolveExpression( Param^.Param, Value, Symb) THEN
            RunWarning( UndefinedWarning);
          IF RangeCheck( Value, 0, WordMask, RangeWarning) THEN
            Value:= Value AND WordMask;
          Memory[ Address + This]:= Value DIV 256;
          Memory[ Address + Succ( This)]:= Value MOD 256;
          Inc( This, 2);
          Param:= Param^.Next;
        END;
      ListInstruction( Address, 2 * Count, Instruct, Count);
    END;
END;
-------------------------------------------------------------------------------

and after:

-------------------------------------------------------------------------------
Static Void EncodeDwToken(Instruct, Reg, Symb)
InstRecord *Instruct;
SymbolRecord *Reg, *Symb;
{
    ParamRecord *Param;
    int Value;
    uchar This;

    This = 0;
    Value = 0;
    Param = Instruct->Params;
    while (Param != NULL) {
	if (!ResolveExpression(Param->Param, &Value, Symb))
	    RunWarning(UndefinedWarning);
	if (RangeCheck(Value, 0, WordMask, RangeWarning))
	    Value &= WordMask;
	Memory[Instruct->Address + This - StartAddress] = Value / 256;
	Memory[Instruct->Address + This - StartAddress + 1] = Value & 255;
	This += 2;
	Param = Param->Next;
    }
    ListInstruction(Instruct->Address, Instruct->Count * 2, Instruct,
		    Instruct->Count);
}
-------------------------------------------------------------------------------

     It's very nice.

     -- Darryl Okahata
	Internet: darrylo%sr@relay.hp.com

P.S. -- For those people who would like a version of p2c that runs under
	MSDOS: don't ask me about it.  While it might be possible if p2c
	was compiled using a DOS extender, it would be a lot of work,
	take up enourmous amounts of memory (a 386 would be a MUST), and
	it would not work under Windows 3.0 (it would have to use
	extended -- not expanded -- memory).

DISCLAIMER: this message is the author's personal opinion and does not
constitute the support, opinion or policy of Hewlett-Packard or of the
little green men that have been following him all day.