well formed flag ?

From	Chris Hinsley <chris.hinsley@gmail.com>
Newsgroups	comp.lang.forth
Date	2012-10-27 15:59 +0100
Message-ID	<2012102715594849117-chrishinsley@gmailcom> (permalink)
Subject	well formed flag ?

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Folks, I'm doing some tweaking to my hobby Forth compiler and just been 
doing some inlineing work.

I'm not very happy about the size of the x86 code for comparision words 
(I know I could reduce the code size if I had a full optimizing code 
generator, but I don't yet…) this is my code for "<"

	defword ">", 0, WORD_GT, WORD_INLINE_COMMA
	POPDSP eax
	cmp eax, ebx
	setg bl
	movzx ebx, bl
	neg ebx
	ret
	defword_end

I followed the 'well formed flag' comments in Ms Rathers book for this, 
but the IF and TRUE, FALSE words only talk about 0 for false or not 
zero for true. Is it definately the case that Forth needs -1 to come 
from the comparason words ?

Are you allowed to write code that _needs_ the -1 from the ">" ? ie if 
it produce just a 1, would that be incorrect ?

Chris

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well formed flag ? Chris Hinsley <chris.hinsley@gmail.com> - 2012-10-27 15:59 +0100
  Re: well formed flag ? Chris Hinsley <chris.hinsley@gmail.com> - 2012-10-27 16:03 +0100
    Re: well formed flag ? Alex McDonald <blog@rivadpm.com> - 2012-10-27 08:33 -0700
      Re: well formed flag ? Alex McDonald <blog@rivadpm.com> - 2012-10-27 09:06 -0700
        Re: well formed flag ? Alex McDonald <blog@rivadpm.com> - 2012-10-27 09:26 -0700
          Re: well formed flag ? Chris Hinsley <chris.hinsley@gmail.com> - 2012-10-27 20:33 +0100
            Re: well formed flag ? Chris Hinsley <chris.hinsley@gmail.com> - 2012-10-27 20:38 +0100
            Re: well formed flag ? Alex McDonald <blog@rivadpm.com> - 2012-10-27 12:52 -0700
              Re: well formed flag ? Chris Hinsley <chris.hinsley@gmail.com> - 2012-10-27 21:01 +0100
                Re: well formed flag ? Coos Haak <chforth@hccnet.nl> - 2012-10-27 22:18 +0200
                Re: well formed flag ? "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2012-10-28 04:19 -0400
        Re: well formed flag ? Chris Hinsley <chris.hinsley@gmail.com> - 2012-10-27 17:44 +0100
          Re: well formed flag ? "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2012-10-27 14:52 -0400
            Re: well formed flag ? Chris Hinsley <chris.hinsley@gmail.com> - 2012-10-27 20:06 +0100
        Re: well formed flag ? Chris Hinsley <chris.hinsley@gmail.com> - 2012-10-27 19:25 +0100
          Re: well formed flag ? Chris Hinsley <chris.hinsley@gmail.com> - 2012-10-27 19:33 +0100
          Re: well formed flag ? Alex McDonald <blog@rivadpm.com> - 2012-10-27 15:08 -0700
            Re: well formed flag ? Chris Hinsley <chris.hinsley@gmail.com> - 2012-10-28 00:53 +0100
  Re: well formed flag ? Mark Wills <forthfreak@gmail.com> - 2012-10-27 09:31 -0700
    Re: well formed flag ? "A. K." <akk@nospam.org> - 2012-10-27 19:21 +0200
      Re: well formed flag ? Mark Wills <forthfreak@gmail.com> - 2012-10-27 10:33 -0700
        Re: well formed flag ? Coos Haak <chforth@hccnet.nl> - 2012-10-27 22:21 +0200
        Re: well formed flag ? "Ed" <invalid@nospam.com> - 2012-10-28 12:33 +1100
          Re: well formed flag ? "Elizabeth D. Rather" <erather@forth.com> - 2012-10-27 15:46 -1000
  Re: well formed flag ? "Elizabeth D. Rather" <erather@forth.com> - 2012-10-27 08:54 -1000
    Re: well formed flag ? Chris Hinsley <chris.hinsley@gmail.com> - 2012-10-27 20:11 +0100
  Re: well formed flag ? "Ed" <invalid@nospam.com> - 2012-10-28 11:05 +1100
    Re: well formed flag ? stephenXXX@mpeforth.com (Stephen Pelc) - 2012-10-28 11:53 +0000
      Re: well formed flag ? Bernd Paysan <bernd.paysan@gmx.de> - 2012-10-28 14:17 +0100
        Re: well formed flag ? mhx@iae.nl (Marcel Hendrix) - 2012-10-28 16:59 +0200
          Re: well formed flag ? Bernd Paysan <bernd.paysan@gmx.de> - 2012-10-28 18:37 +0100
        Re: well formed flag ? "Ed" <invalid@nospam.com> - 2012-10-29 23:46 +1100
          Re: well formed flag ? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-10-29 08:33 -0500
            Re: well formed flag ? Paul Rubin <no.email@nospam.invalid> - 2012-10-29 08:25 -0700
              Re: well formed flag ? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-10-29 12:27 -0500
                Re: well formed flag ? Paul Rubin <no.email@nospam.invalid> - 2012-10-30 08:18 -0700
                Re: well formed flag ? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-10-30 10:33 -0500
                Re: well formed flag ? Paul Rubin <no.email@nospam.invalid> - 2012-10-30 08:48 -0700
                Re: well formed flag ? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-10-30 11:45 -0500
                Re: well formed flag ? Bernd Paysan <bernd.paysan@gmx.de> - 2012-10-30 20:10 +0100
                Re: well formed flag ? Alex McDonald <blog@rivadpm.com> - 2012-10-30 15:10 -0700
                Re: well formed flag ? Paul Rubin <no.email@nospam.invalid> - 2012-10-30 18:28 -0700
                Re: well formed flag ? Alex McDonald <blog@rivadpm.com> - 2012-11-02 05:28 -0700
                Re: well formed flag ? Paul Rubin <no.email@nospam.invalid> - 2012-11-02 08:13 -0700
                Re: well formed flag ? "Elizabeth D. Rather" <erather@forth.com> - 2012-10-30 12:50 -1000
                Re: well formed flag ? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-10-31 14:57 +0000
                Re: well formed flag ? Bernd Paysan <bernd.paysan@gmx.de> - 2012-10-31 17:58 +0100
                Re: well formed flag ? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-10-31 17:39 +0000
                Re: well formed flag ? David Thompson <dave.thompson2@verizon.net> - 2012-11-16 23:21 -0500
                Aliasing (was: well formed flag ?) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-10-31 14:03 +0000
                Re: well formed flag ? "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2012-10-31 12:06 -0400
                Re: well formed flag ? Paul Rubin <no.email@nospam.invalid> - 2012-10-31 09:31 -0700
                Aliases (was: well formed flag ?) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-10-31 17:02 +0000
                Re: well formed flag ? "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2012-10-31 20:06 -0400
      Re: well formed flag ? "Ed" <invalid@nospam.com> - 2012-10-29 23:47 +1100
        Re: well formed flag ? stephenXXX@mpeforth.com (Stephen Pelc) - 2012-10-30 18:02 +0000
          Re: well formed flag ? "Ed" <invalid@nospam.com> - 2012-10-31 11:44 +1100
            Re: well formed flag ? stephenXXX@mpeforth.com (Stephen Pelc) - 2012-10-31 09:25 +0000

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