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Re: Integer cosine function

From Bernd Paysan <bernd.paysan@gmx.de>
Newsgroups comp.lang.forth
Subject Re: Integer cosine function
Date 2013-03-06 16:39 +0100
Organization 1&1 Internet AG
Message-ID <kh7o0e$v9a$1@online.de> (permalink)
References (10 earlier) <slrnkif6cd.db8.zbigniew2011REMOVE@Tichy.myhome.org> <kg87bo$ss9$1@online.de> <55e44f69-28e2-41ee-8248-4f0bd54b114a@l13g2000yqe.googlegroups.com> <kg92jf$g5g$1@online.de> <f230c9be-d249-4a4b-b4b3-9a8bbcd0b9e4@y2g2000pbg.googlegroups.com>

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Hugh Aguilar wrote:

> On Feb 22, 5:30 pm, Bernd Paysan <bernd.pay...@gmx.de> wrote:
>> Hugh Aguilar wrote:
>> > All in all, the 8051 was a very good design for its day. The only bad
>> > thing about the 8051 was that it didn't support high-level languages
>> > very well, but that really wasn't what it was designed for.
>>
>> Fully agreed.  But when your customer wants to deliberately use a HLL for
>> his application, then chosing the 8051 is stupid.  And it wasn't a
>> PLC-like controller, it was something that had to do calculations most of
>> the time.
> 
> The way that C worked on the 8051, was to hold the current stack-frame
> in low-memory and use absolute addressing to get at the locals. For
> every function call, the parent's stack-frame was moved to high-memory
> and the child's stack-frame was moved into low-memory. Moving the
> stack-frame in and out for every function call made function calls
> pretty slow. Also, it was impossible to use & to obtain the address of
> a local variable --- so the result wasn't really C at all, but was
> just a C-like language.

Actually, the Keil compiler does better if there's no recursive call, and 
all the stack frames fit together in low memory.

> Forth was worse though! In Forth, the parameter stack was low-memory.
> Pointers had to be adjusted up and down to get at the data. There were
> only 2 pointers though (R0 and R1), so this was a major PITA. All in
> all, the 8051's lack of an indexed addressing mode really crippled it.

Yes.  If you compare the 8051 to something comparable of that era, e.g. the 
6502, you see how bad it is for implementing a HLL.  The 6502 has a better 
approach at low memory, the zero page: It just is the first 256 bytes of the 
memory map, it is easy to access with single bytes.  And it has indexed 
memory access.

> It might have been possible to write a Forth that stored stack
> parameters in absolute locations, so absolute addressing could be
> done. This would require an analytical optimizer. I have never heard
> of this being done. I don't know if it would be possible or not.

It should be possible with about the same limitations of the Keil compiler: 
Cross-compilation only (because it won't fit into the 8051), and no 
recursive functions.

-- 
Bernd Paysan
"If you want it done right, you have to do it yourself"
http://bernd-paysan.de/

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Thread

Integer cosine function Brad Eckert <hwfwguy@gmail.com> - 2013-02-16 07:35 -0800
  Re: Integer cosine function mhx@iae.nl (Marcel Hendrix) - 2013-02-17 13:57 +0200
    Re: Integer cosine function Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-02-17 09:40 -0600
      Re: Integer cosine function "Elizabeth D. Rather" <erather@forth.com> - 2013-02-17 07:51 -1000
        Re: Integer cosine function mhx@iae.nl (Marcel Hendrix) - 2013-02-17 19:06 +0200
          Re: Integer cosine function anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-02-18 14:46 +0000
          Re: Integer cosine function Zbiggy <zbigniew2011REMOVE@gmail.REMOVE.com> - 2013-02-19 20:01 +0100
            Re: Integer cosine function mhx@iae.nl (Marcel Hendrix) - 2013-02-19 21:34 +0200
              Re: Integer cosine function Zbiggy <zbigniew2011REMOVE@gmail.REMOVE.com> - 2013-02-19 21:46 +0100
            Re: Integer cosine function Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-02-19 15:55 -0800
              Re: Integer cosine function Coos Haak <chforth@hccnet.nl> - 2013-02-21 00:59 +0100
        Re: Integer cosine function Brad Eckert <hwfwguy@gmail.com> - 2013-02-18 09:19 -0800
          Re: Integer cosine function rickman <gnuarm@gmail.com> - 2013-02-18 14:27 -0500
          Re: Integer cosine function Bernd Paysan <bernd.paysan@gmx.de> - 2013-02-18 20:53 +0100
            Re: Integer cosine function Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-02-18 19:10 -0800
              Re: Integer cosine function Bernd Paysan <bernd.paysan@gmx.de> - 2013-02-19 13:13 +0100
              Re: Integer cosine function rickman <gnuarm@gmail.com> - 2013-02-19 23:04 -0500
            Re: Integer cosine function Gary Bergstrom <g.bergstrom@ieee.org> - 2013-02-20 10:00 -0800
              Re: Integer cosine function Bernd Paysan <bernd.paysan@gmx.de> - 2013-02-21 13:04 +0100
                Re: Integer cosine function rickman <gnuarm@gmail.com> - 2013-02-21 19:03 -0500
                Re: Integer cosine function Bernd Paysan <bernd.paysan@gmx.de> - 2013-02-22 02:45 +0100
                Re: Integer cosine function Mark Wills <markrobertwills@yahoo.co.uk> - 2013-02-22 02:32 -0800
                Re: Integer cosine function Bernd Paysan <bernd.paysan@gmx.de> - 2013-02-22 16:01 +0100
                Re: Integer cosine function Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-02-22 22:07 -0800
                Re: Integer cosine function "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2013-02-23 10:27 -0500
                Re: Integer cosine function Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-02-22 03:59 -0600
                Re: Integer cosine function Mark Wills <markrobertwills@yahoo.co.uk> - 2013-02-22 02:30 -0800
                Re: Integer cosine function Bernd Paysan <bernd.paysan@gmx.de> - 2013-02-22 15:56 +0100
                Re: Integer cosine function Zbiggy <zbigniew2011REMOVE@gmail.REMOVE.com> - 2013-02-22 16:13 +0100
                Re: Integer cosine function Bernd Paysan <bernd.paysan@gmx.de> - 2013-02-22 17:45 +0100
                Re: Integer cosine function Zbiggy <zbigniew2011REMOVE@gmail.REMOVE.com> - 2013-02-22 18:44 +0100
                Re: Integer cosine function Bernd Paysan <bernd.paysan@gmx.de> - 2013-02-22 19:19 +0100
                Re: Integer cosine function Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-02-22 14:43 -0800
                Re: Integer cosine function Bernd Paysan <bernd.paysan@gmx.de> - 2013-02-23 01:30 +0100
                Re: Integer cosine function Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-02-22 21:51 -0800
                Re: Integer cosine function Bernd Paysan <bernd.paysan@gmx.de> - 2013-02-24 01:43 +0100
                Re: Integer cosine function anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-02-25 17:55 +0000
                Re: Integer cosine function Bernd Paysan <bernd.paysan@gmx.de> - 2013-02-25 21:01 +0100
                Re: Integer cosine function Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-02-25 23:22 -0800
                Re: Integer cosine function Bernd Paysan <bernd.paysan@gmx.de> - 2013-02-26 15:11 +0100
                Re: Integer cosine function rickman <gnuarm@gmail.com> - 2013-02-27 08:05 -0500
                Re: Integer cosine function "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2013-02-27 22:14 -0500
                Re: Integer cosine function rickman <gnuarm@gmail.com> - 2013-02-27 22:56 -0500
                Re: Integer cosine function "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2013-03-01 21:37 -0500
                Re: Integer cosine function rickman <gnuarm@gmail.com> - 2013-03-07 13:12 -0500
                Re: Integer cosine function Brad Eckert <hwfwguy@gmail.com> - 2013-02-28 08:00 -0800
                Re: Integer cosine function "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2013-03-01 21:38 -0500
                Re: Integer cosine function Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2013-02-28 16:55 +0000
                Re: Integer cosine function "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2013-03-01 21:38 -0500
                Re: Integer cosine function Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2013-03-04 11:08 +0000
                Re: Integer cosine function Mark Wills <markrobertwills@yahoo.co.uk> - 2013-03-04 03:39 -0800
                Re: Integer cosine function "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2013-03-04 20:49 -0500
                Re: Integer cosine function stephenXXX@mpeforth.com (Stephen Pelc) - 2013-03-05 10:20 +0000
                Re: Integer cosine function Mark Wills <markrobertwills@yahoo.co.uk> - 2013-03-07 00:12 -0800
                Re: Integer cosine function "Rod Pemberton" <do_not_have@notemailnotq.cpm> - 2013-03-08 04:21 -0500
                Re: Integer cosine function "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2013-03-04 20:50 -0500
                Re: Integer cosine function Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2013-03-05 07:16 +0000
                Re: Integer cosine function "Rod Pemberton" <do_not_have@notemailnotq.cpm> - 2013-03-06 17:56 -0500
                Re: Integer cosine function Mark Wills <markrobertwills@yahoo.co.uk> - 2013-03-07 00:24 -0800
                Re: Integer cosine function Mark Wills <markrobertwills@yahoo.co.uk> - 2013-03-07 07:34 -0800
                Re: Integer cosine function Lars Brinkhoff <lars.spam@nocrew.org> - 2013-02-28 12:57 +0100
                Re: Integer cosine function Bernd Paysan <bernd.paysan@gmx.de> - 2013-02-28 17:07 +0100
                Re: Integer cosine function Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-02-28 19:37 -0800
                Re: Integer cosine function stephenXXX@mpeforth.com (Stephen Pelc) - 2013-03-01 10:56 +0000
                Re: Integer cosine function anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-03-01 13:52 +0000
                Re: Integer cosine function Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-03-05 17:48 -0800
                Re: Integer cosine function rickman <gnuarm@gmail.com> - 2013-03-13 17:44 -0400
                Re: Integer cosine function "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2013-03-01 21:36 -0500
                Re: Integer cosine function Elizabeth D Rather <erather@forth.com> - 2013-03-01 19:14 -1000
                Re: Integer cosine function mhx@iae.nl (Marcel Hendrix) - 2013-03-02 09:34 +0200
                Re: Integer cosine function kenney@cix.compulink.co.uk - 2013-03-02 09:06 -0600
                Re: Integer cosine function Brad Eckert <hwfwguy@gmail.com> - 2013-02-26 08:53 -0800
                Re: Integer cosine function "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2013-02-26 16:59 -0500
                Re: Integer cosine function albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-02-27 00:52 +0000
                Re: Integer cosine function "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2013-02-27 04:07 -0500
                Re: Integer cosine function "WJ" <w_a_x_man@yahoo.com> - 2013-03-05 20:51 +0000
                Re: Integer cosine function Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-03-05 17:58 -0800
                Re: Integer cosine function Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-06 16:39 +0100
                Re: Integer cosine function Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-03-06 14:21 -0800
                Re: Integer cosine function Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-07 00:11 +0100
                Re: Integer cosine function albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-03-06 23:44 +0000
                Re: Integer cosine function Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-03-06 16:24 -0800
                Re: Integer cosine function Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-07 01:59 +0100
                Re: Integer cosine function Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-03-06 19:48 -0800
                Re: Integer cosine function Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-07 16:22 +0100
                Re: Integer cosine function "WJ" <w_a_x_man@yahoo.com> - 2013-03-06 23:37 +0000
                Re: Integer cosine function "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2013-02-23 09:54 -0500
                Re: Integer cosine function "WJ" <w_a_x_man@yahoo.com> - 2013-03-05 21:03 +0000
                Re: Integer cosine function Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-03-05 15:59 -0800
                Re: Integer cosine function Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-03-05 16:38 -0800
                Re: Integer cosine function Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-02-22 12:07 -0600
                Re: Integer cosine function Bernd Paysan <bernd.paysan@gmx.de> - 2013-02-22 19:39 +0100
                Re: Integer cosine function "Elizabeth D. Rather" <erather@forth.com> - 2013-02-22 09:23 -1000
                Re: Integer cosine function Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-02-23 04:44 -0600
                Re: Integer cosine function Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-02-22 13:00 -0800
                Re: Integer cosine function Bernd Paysan <bernd.paysan@gmx.de> - 2013-02-23 01:09 +0100
                Re: Integer cosine function rickman <gnuarm@gmail.com> - 2013-02-22 21:16 -0500
                Re: Integer cosine function rickman <gnuarm@gmail.com> - 2013-02-22 20:28 -0500
  Re: Integer cosine function Gary Bergstrom <g.bergstrom@ieee.org> - 2013-02-27 07:59 -0800
    Re: Integer cosine function Brad Eckert <hwfwguy@gmail.com> - 2013-02-27 08:48 -0800
      Re: Integer cosine function Gary Bergstrom <g.bergstrom@ieee.org> - 2013-02-27 10:23 -0800
      Re: Integer cosine function Gary Bergstrom <g.bergstrom@ieee.org> - 2013-03-15 10:14 -0700
        Re: Integer cosine function Brad Eckert <hwfwguy@gmail.com> - 2013-03-15 13:19 -0700
          Re: Integer cosine function Brad Eckert <hwfwguy@gmail.com> - 2013-03-15 13:28 -0700
            Re: Integer cosine function Gary Bergstrom <g.bergstrom@ieee.org> - 2013-03-15 21:13 -0700

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