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Re: OT (slightly) What is the "best" processor for a new project?

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On Wednesday, July 3, 2013 2:30:07 AM UTC-7, Rod Pemberton wrote:
> <hughaguilar96@yahoo.com> wrote in message
> news:dc1b1c8b-3ea7-4ea6-9ff5-9f0edc7c2d48@googlegroups.com...
> 
> > If you are going to have any speed, then it is necessary
> > to make primitives out of common combos.
> 
> Hugh, I've already told you, like three times now, that this
> premise doesn't follow, mathematically.
> 
> > For example: OVER_+ should be a primitive. This is
> > generally faster than OVER followed by +, and it
> > halves the memory usage in the threaded code.
> 
> The probability of any Forth instruction being executed is really
> low, even for the heavy usage instructions, of which there are only
> a few.  See the work by Philip Koopman or Anton Ertl on instruction
> frequencies.  The probability of any combination of two operations
> being executed is even lower, substantially lower in fact.  So, how
> exactly can optimizing a bunch of extremely low use operations
> result in faster performance?  These combinations would have to
> execute many, many times to have any measurable effect.  Just how
> is that going to happen?  How many times are you going to code
> "OVER +" in typical code?  How many times is it going to execute?

This is an argument against the B16 design, not against the MiniForth design!

The B16 packs three 5-bit codes together into a single 16-bit cell. So, as daveyrotten says, you effectively have 32^3=32768 primitives. But the vast majority of those combos will never appear in any program, and most will appear only very rarely. Less than 500 will get much use at all.

What I have found (relying on casual inspection with a heavy dose of intuition), is that Forth code mostly alternates between "producers" and "consumers." You have words that push data onto the stack, followed by words that remove data from the stack. OVER_+ is a classic example: OVER is a producer and + is a consumer. In my CAMForth, the majority if my hundreds of primitives are producer-consumer pairs. These are not only common, but they also lend themselves to being written as a pair --- because they can hold the data in a register internally, rather than push it onto the stack and then immediately pop it off the stack.

The B16 is not using registers to hold data internally for producer-consumer pairs such as OVER followed by +. It is just using memory --- pushing the data onto the stack and then immediately popping the data off the stack.

> So, I think it's high time to ask your mathematics "professor"
> brother to explain the "essence" of probability to you.

Leave my family out of this, you whoreson troll!

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Re: OT (slightly) What is the "best" processor for a new project? Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-06-16 23:17 -0700
  Re: OT (slightly) What is the "best" processor for a new project? Bernd Paysan <bernd.paysan@gmx.de> - 2013-06-17 14:19 +0200
    Re: OT (slightly) What is the "best" processor for a new project? Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-06-17 16:04 -0700
    Re: OT (slightly) What is the "best" processor for a new project? Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-06-17 16:15 -0700
      Re: OT (slightly) What is the "best" processor for a new project? rickman <gnuarm@gmail.com> - 2013-06-18 00:01 -0400
        Re: OT (slightly) What is the "best" processor for a new project? Bernd Paysan <bernd.paysan@gmx.de> - 2013-06-19 15:33 +0200
          Re: OT (slightly) What is the "best" processor for a new project? rickman <gnuarm@gmail.com> - 2013-06-19 17:25 -0400
            Re: OT (slightly) What is the "best" processor for a new project? Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-06-19 17:00 -0700
              Re: OT (slightly) What is the "best" processor for a new project? rickman <gnuarm@gmail.com> - 2013-06-20 18:35 -0400
          Re: OT (slightly) What is the "best" processor for a new project? Hugh Aguilar <hughaguilar96@yahoo.com> - 2013-06-19 17:38 -0700
            Re: OT (slightly) What is the "best" processor for a new project? Bernd Paysan <bernd.paysan@gmx.de> - 2013-06-20 12:51 +0200
              Re: OT (slightly) What is the "best" processor for a new project? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-06-20 15:28 +0000
              Re: OT (slightly) What is the "best" processor for a new project? hughaguilar96@yahoo.com - 2013-06-20 18:39 -0700
                Re: OT (slightly) What is the "best" processor for a new project? Bernd Paysan <bernd.paysan@gmx.de> - 2013-06-21 14:50 +0200
                Re: OT (slightly) What is the "best" processor for a new project? hughaguilar96@yahoo.com - 2013-06-22 18:56 -0700
                Re: OT (slightly) What is the "best" processor for a new project? "WJ" <w_a_x_man@yahoo.com> - 2013-06-23 02:35 +0000
                Re: OT (slightly) What is the "best" processor for a new project? hughaguilar96@yahoo.com - 2013-06-22 20:48 -0700
                Re: OT (slightly) What is the "best" processor for a new project? Bernd Paysan <bernd.paysan@gmx.de> - 2013-06-23 14:49 +0200
                Re: OT (slightly) What is the "best" processor for a new project? hughaguilar96@yahoo.com - 2013-06-26 18:08 -0700
                Re: OT (slightly) What is the "best" processor for a new project? Bernd Paysan <bernd.paysan@gmx.de> - 2013-06-27 16:32 +0200
                Re: OT (slightly) What is the "best" processor for a new project? hughaguilar96@yahoo.com - 2013-06-30 10:10 -0700
                Re: OT (slightly) What is the "best" processor for a new project? rickman <gnuarm@gmail.com> - 2013-06-30 15:18 -0400
                Re: OT (slightly) What is the "best" processor for a new project? hughaguilar96@yahoo.com - 2013-06-30 16:01 -0700
                Re: OT (slightly) What is the "best" processor for a new project? rickman <gnuarm@gmail.com> - 2013-06-30 20:22 -0400
                Re: OT (slightly) What is the "best" processor for a new project? Bernd Paysan <bernd.paysan@gmx.de> - 2013-06-30 21:22 +0200
                Re: OT (slightly) What is the "best" processor for a new project? hughaguilar96@yahoo.com - 2013-06-30 15:52 -0700
                Re: OT (slightly) What is the "best" processor for a new project? Bernd Paysan <bernd.paysan@gmx.de> - 2013-07-01 02:02 +0200
                Re: OT (slightly) What is the "best" processor for a new project? hughaguilar96@yahoo.com - 2013-06-30 19:25 -0700
                Re: OT (slightly) What is the "best" processor for a new project? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-07-01 02:34 -0500
                Re: OT (slightly) What is the "best" processor for a new project? rickman <gnuarm@gmail.com> - 2013-07-01 16:26 -0400
                Re: OT (slightly) What is the "best" processor for a new project? Bernd Paysan <bernd.paysan@gmx.de> - 2013-07-01 23:08 +0200
                Re: OT (slightly) What is the "best" processor for a new project? rickman <gnuarm@gmail.com> - 2013-07-01 18:10 -0400
                Re: OT (slightly) What is the "best" processor for a new project? "Elizabeth D. Rather" <erather@forth.com> - 2013-07-01 12:35 -1000
                Re: OT (slightly) What is the "best" processor for a new project? rickman <gnuarm@gmail.com> - 2013-07-01 18:42 -0400
                Re: OT (slightly) What is the "best" processor for a new project? "Elizabeth D. Rather" <erather@forth.com> - 2013-07-01 13:03 -1000
                Re: OT (slightly) What is the "best" processor for a new project? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-07-02 07:20 +0000
                Re: OT (slightly) What is the "best" processor for a new project? "Elizabeth D. Rather" <erather@forth.com> - 2013-07-02 07:38 -1000
                Re: OT (slightly) What is the "best" processor for a new project? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-07-02 07:24 +0000
                Re: OT (slightly) What is the "best" processor for a new project? Bernd Paysan <bernd.paysan@gmx.de> - 2013-07-02 13:02 +0200
                Re: OT (slightly) What is the "best" processor for a new project? "Rod Pemberton" <do_not_have@notemailnotq.cpm> - 2013-07-02 05:58 -0400
                Re: OT (slightly) What is the "best" processor for a new project? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-07-02 03:34 -0500
                Re: OT (slightly) What is the "best" processor for a new project? hughaguilar96@yahoo.com - 2013-07-01 20:01 -0700
                Re: OT (slightly) What is the "best" processor for a new project? "WJ" <w_a_x_man@yahoo.com> - 2013-07-02 04:43 +0000
                Re: OT (slightly) What is the "best" processor for a new project? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-07-02 03:41 -0500
                Re: OT (slightly) What is the "best" processor for a new project? "Rod Pemberton" <do_not_have@notemailnotq.cpm> - 2013-07-02 06:09 -0400
                Re: OT (slightly) What is the "best" processor for a new project? hughaguilar96@yahoo.com - 2013-07-02 13:51 -0700
                Re: OT (slightly) What is the "best" processor for a new project? daveyrotten <danw8804@gmail.com> - 2013-07-02 14:37 -0700
                Re: OT (slightly) What is the "best" processor for a new project? daveyrotten <danw8804@gmail.com> - 2013-07-02 14:56 -0700
                Re: OT (slightly) What is the "best" processor for a new project? Bernd Paysan <bernd.paysan@gmx.de> - 2013-07-03 00:30 +0200
                Re: OT (slightly) What is the "best" processor for a new project? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-07-03 02:19 -0500
                Re: OT (slightly) What is the "best" processor for a new project? "Rod Pemberton" <do_not_have@notemailnotq.cpm> - 2013-07-03 05:18 -0400
                Re: OT (slightly) What is the "best" processor for a new project? hughaguilar96@yahoo.com - 2013-07-03 18:10 -0700
                Re: OT (slightly) What is the "best" processor for a new project? "Rod Pemberton" <do_not_have@notemailnotq.cpm> - 2013-07-03 05:30 -0400
                Static superinstructions(was: OT (slightly) What is the "best" ...) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-07-03 14:33 +0000
                Re: Static superinstructions(was: OT (slightly) What is the "best" ...) Bernd Paysan <bernd.paysan@gmx.de> - 2013-07-04 00:41 +0200
                Re: Static superinstructions(was: OT (slightly) What is the "best" ...) "Rod Pemberton" <do_not_have@notemailnotq.cpm> - 2013-07-07 11:32 -0400
                Re: OT (slightly) What is the "best" processor for a new project? hughaguilar96@yahoo.com - 2013-07-03 18:31 -0700
                Re: OT (slightly) What is the "best" processor for a new project? "Rod Pemberton" <do_not_have@notemailnotq.cpm> - 2013-07-07 11:28 -0400
                Re: OT (slightly) What is the "best" processor for a new project? rickman <gnuarm@gmail.com> - 2013-07-02 16:44 -0400
                Re: OT (slightly) What is the "best" processor for a new project? "Rod Pemberton" <do_not_have@notemailnotq.cpm> - 2013-07-02 05:56 -0400
                Re: OT (slightly) What is the "best" processor for a new project? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-07-02 05:58 -0500
                Re: OT (slightly) What is the "best" processor for a new project? "Rod Pemberton" <do_not_have@notemailnotq.cpm> - 2013-07-03 05:57 -0400
                Re: OT (slightly) What is the "best" processor for a new project? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-07-03 06:43 -0500
                Re: OT (slightly) What is the "best" processor for a new project? rickman <gnuarm@gmail.com> - 2013-06-30 20:29 -0400
                Re: OT (slightly) What is the "best" processor for a new project? rickman <gnuarm@gmail.com> - 2013-06-27 10:58 -0400

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