Mephisto Chess Genius
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Re: Mephisto Chess Genius
If permission could be obtained, would it be feasible to decompile then recompile the code?
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Re: Mephisto Chess Genius
There is nothing to decompile because it wasn't compiled in the first place. It's handwritten assembly, so an assembler was used. That's a stage after the compiler, so there is no original C source that you could try to recover. Even worse, the structure of handwritten assembly often doesn't map well to a higher level language because you can do all sorts of dirty tricks in assembly to get the last drop of performance.
I think Lang ported the whole engine to C at some later point.
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Re: Mephisto Chess Genius
As close as you're going to get is 3 of Langs championship Mephisto modules as UCI in Rebels Gideon Pro UCI package. You can find it on the web.
Last edited by Jjaw on Mon Jan 13, 2025 11:26 pm, edited 1 time in total.
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Re: Mephisto Chess Genius
Ras wrote: ↑Mon Jan 13, 2025 8:47 pmThere is nothing to decompile because it wasn't compiled in the first place. It's handwritten assembly, so an assembler was used. That's a stage after the compiler, so there is no original C source that you could try to recover. Even worse, the structure of handwritten assembly often doesn't map well to a higher level language because you can do all sorts of dirty tricks in assembly to get the last drop of performance.
Yes - very good point.
It is possible to convert assembly to a high level languages - e.g. link.
However, some caveats:
1. Because it's an AI tool, it's probably not as good as a hand-written (reverse) compiler
2. Even if it did get everything right, there's still a strong possibility that it will make some moves differently at the same stage in its calculations because different parts of the code may not be quite so well tuned to each other
Probably best to make a case to Mr Lang to release his own port to C to open source.
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Re: Mephisto Chess Genius
No, Stefan was not in Santiago, the Shredder engine is still available.Paloma wrote: ↑Mon Jan 13, 2025 1:46 pmStefan Meyer-Kahlen was also in Santiago, right?Engin wrote: ↑Mon Jan 13, 2025 11:49 ami ask him in Santiago why is it only 32bit and if its possible to port it to 64 bit, but he answered that takes to much work to rewrite it for 64 bit.
so i need a tool for old 32 bits EXE files to run that on 64 bit windows, i had got it run with Virtualbox on 32 bit windows, but i want run it on 64 bit.
Has anyone there heard if there is still a Shredder 14?
Or is the Shredder Project dead?
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Re: Mephisto Chess Genius
why it is working on linux but not on windows 64 bit ?Ras wrote: ↑Mon Jan 13, 2025 6:00 pm64 bit Windows can run 32 bit applications just fine. What 64 bit Windows cannot do, is running 16 bit code - but 32 bit Windows can do that.
Specifically for ChessGenius, the earlier versions were for MS-DOS, so 16 bit code. What has happened is that Lang slapped a Windows GUI on the existing DOS-engine, and this GUI is in fact 32 bit as per the executable's header, but the engine underneath (GENG7.EXE) is still 16 bit code. What's more, it's hand-coded assembly. Porting that would indeed be a lot of work, so it's not going to happen for an old engine version.
However, ChessGenius 7.2 does run under 64 bit Linux with Wine, at least I was able to install it, start it, and play some moves in the demo version.
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Re: Mephisto Chess Genius
if he has ported to C then it should more easier to compile it for 64 bit i guess or ?Ras wrote: ↑Mon Jan 13, 2025 8:47 pmThere is nothing to decompile because it wasn't compiled in the first place. It's handwritten assembly, so an assembler was used. That's a stage after the compiler, so there is no original C source that you could try to recover. Even worse, the structure of handwritten assembly often doesn't map well to a higher level language because you can do all sorts of dirty tricks in assembly to get the last drop of performance.
I think Lang ported the whole engine to C at some later point.
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Re: Mephisto Chess Genius
That i hope too, then the C code can be easy compile to 64 bittowforce wrote: ↑Mon Jan 13, 2025 11:22 pmRas wrote: ↑Mon Jan 13, 2025 8:47 pmThere is nothing to decompile because it wasn't compiled in the first place. It's handwritten assembly, so an assembler was used. That's a stage after the compiler, so there is no original C source that you could try to recover. Even worse, the structure of handwritten assembly often doesn't map well to a higher level language because you can do all sorts of dirty tricks in assembly to get the last drop of performance.
Yes - very good point.
It is possible to convert assembly to a high level languages - e.g. link.
However, some caveats:
1. Because it's an AI tool, it's probably not as good as a hand-written (reverse) compiler
2. Even if it did get everything right, there's still a strong possibility that it will make some moves differently at the same stage in its calculations because different parts of the code may not be quite so well tuned to each other
Probably best to make a case to Mr Lang to release his own port to C to open source.
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Re: Mephisto Chess Genius
I do not think shredder is continued. There is no new shredder version in the last years.
In opposite to new colossus versions.
Richard lang , like Ed Schroeder, „retired“ from commercial computer chess .
His motorola 680x0 versions were assembler. Later engines were imo not assembler but C.
The motorola versions were the foundation of his success with Hegener and Glaser and Ossi Weiner.
Although Richard Lang did work before HG for David Levy.
His 8bit engine was sold as Cyrus and Cyrus II on many machines. Then dedicated chess computers for hanimex and cxg and other companies. After 1984 came the Hegener and Glaser age.
With many championship titles such as in amsterdam, dallas, rome, almeria, portorose, vancouver…
Richard was in Santiago de Compostela.
Almost any participant there made selfies with „King Richard“.
In opposite to new colossus versions.
Richard lang , like Ed Schroeder, „retired“ from commercial computer chess .
His motorola 680x0 versions were assembler. Later engines were imo not assembler but C.
The motorola versions were the foundation of his success with Hegener and Glaser and Ossi Weiner.
Although Richard Lang did work before HG for David Levy.
His 8bit engine was sold as Cyrus and Cyrus II on many machines. Then dedicated chess computers for hanimex and cxg and other companies. After 1984 came the Hegener and Glaser age.
With many championship titles such as in amsterdam, dallas, rome, almeria, portorose, vancouver…
Richard was in Santiago de Compostela.
Almost any participant there made selfies with „King Richard“.
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