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Re: 3dup again

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Am 03.10.2025 um 11:02 schrieb albert@spenarnc.xs4all.nl:
> In article <2025Oct2.224440@mips.complang.tuwien.ac.at>,
> Anton Ertl <anton@mips.complang.tuwien.ac.at> wrote:
>> dxf <dxforth@gmail.com> writes:
>>> For 3DUP I believe this is the one to beat:
>>>
>>> : 3DUP ( a b c -- a b c a b c )  dup 2over rot ;
>>>
>>> With NTF/LFX the locals version will break even.
>>
>> As we already discussed in the thread including
>> <2021Sep11.083507@mips.complang.tuwien.ac.at>, NTF/LXF produces the
>> same (optimal for the calling convention used by NTF/LXF) code for
>> 3DUP versions using the data stack, return stack, or locals.  That's
>> because the actual data flow is always the same, and NTF/LXF can see
>> this data flow in all three cases.
> 
> The problem with 3DUP is that it is actually used in context.
> What is the data that is going to 3DUP ped? In my view this
> amounts to double use of data that is in registers (32 in the riscv)
> anyway, after an optimiser does his thing.
> 

Code inlining will mend it.

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Generating a random sequence of Forth words anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2025-09-30 16:33 +0000
  Re: Generating a random sequence of Forth words minforth <minforth@gmx.net> - 2025-10-01 11:20 +0200
    Re: Generating a random sequence of Forth words anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2025-10-01 17:10 +0000
  Re: Generating a random sequence of Forth words Hans Bezemer <the.beez.speaks@gmail.com> - 2025-10-01 17:11 +0200
    Re: Generating a random sequence of Forth words minforth <minforth@gmx.net> - 2025-10-01 20:42 +0200
      Re: Generating a random sequence of Forth words dxf <dxforth@gmail.com> - 2025-10-02 19:49 +1000
        Re: Generating a random sequence of Forth words albert@spenarnc.xs4all.nl - 2025-10-02 13:07 +0200
          Re: Generating a random sequence of Forth words dxf <dxforth@gmail.com> - 2025-10-03 18:22 +1000
        3dup again (was: Generating a random sequence of Forth words) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2025-10-02 20:44 +0000
          Re: 3dup again (was: Generating a random sequence of Forth words) albert@spenarnc.xs4all.nl - 2025-10-03 11:02 +0200
            Re: 3dup again minforth <minforth@gmx.net> - 2025-10-03 11:09 +0200
              Re: 3dup again anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2025-10-04 08:04 +0000
          Re: 3dup again Hans Bezemer <the.beez.speaks@gmail.com> - 2025-10-05 11:29 +0200
  Re: Generating a random sequence of Forth words antispam@fricas.org (Waldek Hebisch) - 2025-10-15 19:19 +0000
    Re: Generating a random sequence of Forth words anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2025-10-24 15:55 +0000

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