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Author Topic: Why MaxDouble does not equal to MaxDouble?  (Read 1935 times)

Thaddy

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Re: Why MaxDouble does not equal to MaxDouble?
« Reply #30 on: October 05, 2024, 07:47:51 pm »
Not, yet, but it should not be difficult to find.
If I smell bad code it usually is bad code and that includes my own code.

bytebites

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Re: Why MaxDouble does not equal to MaxDouble?
« Reply #31 on: October 05, 2024, 07:53:00 pm »
Is there a bingo program too?

tetrastes

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Re: Why MaxDouble does not equal to MaxDouble?
« Reply #32 on: October 05, 2024, 07:57:26 pm »
From https://learn.microsoft.com/en-us/cpp/build/ieee-floating-point-representation?view=msvc-170:

Quote
The IEEE standard also specifies half-precision (2-byte) and quadruple-precision (16-byte) formats, and a double-extended-precision (10-byte) format, which some C and C++ compilers implement as the long double data type. In the MSVC compiler, the long double data type is treated as a distinct type, but the storage type maps to double. There is, however, intrinsic and assembly language support for computations using the other formats, including the double-extended-precision format, where supported by hardware.

So Windows x86_64 ABI does not deprecate the x87 CPU, it, say that, doesn't bother much about that.
« Last Edit: October 05, 2024, 08:35:15 pm by tetrastes »

Thaddy

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Re: Why MaxDouble does not equal to MaxDouble?
« Reply #33 on: October 05, 2024, 09:07:47 pm »
Is there a bingo program too?
Well at least the algorithm demo was already published and and that did everybody else wrong. It will come.
If I smell bad code it usually is bad code and that includes my own code.

Zoran

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Re: Why MaxDouble does not equal to MaxDouble?
« Reply #34 on: October 06, 2024, 06:31:35 am »
If you can not find it on the forum, it is probably on the mailing list.
I could not find it quickly  myself too, but I know it is there.
Much Talk. No show. ;-)

Now this is really rude. >:(

Thaddy told you he remembers there were some instructions that might interest you.
Although he could not find it, the fact that he had seen it once might be helpful to you, so you can try to search, if you are interested.
He might help more and try to find it, but he certainly does not owe that to you.

TRon

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Re: Why MaxDouble does not equal to MaxDouble?
« Reply #35 on: October 06, 2024, 07:09:41 am »
I was able to find this though expressed by PascalDragon.

Took about 15 second to find with ddg  :P
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BrunoK

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Re: Why MaxDouble does not equal to MaxDouble?
« Reply #36 on: October 06, 2024, 12:26:38 pm »
Now this is really rude. >:(

Thaddy told you he remembers there were some instructions that might interest you.
Thaddy bla bla remembers bla bla has written knows all was chief bla bla others are idiots blabla ready to run bla bla. Thaddy knows all.

What Thaddy puts here is usually buggy and very very occasionally ok.

BrunoK

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Re: Why MaxDouble does not equal to MaxDouble?
« Reply #37 on: October 06, 2024, 12:28:05 pm »
I was able to find this though expressed by PascalDragon.

Took about 15 second to find with ddg  :P
Thank you, noted and investigating based on your reply and asssociated link.

B.

BrunoK

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Re: Why MaxDouble does not equal to MaxDouble?
« Reply #38 on: October 06, 2024, 07:15:36 pm »
I was able to find this though expressed by PascalDragon.

Took about 15 second to find with ddg  :P
That is the decisive link.

-dFPC_SUPPORT_X87_TYPES_ON_WIN64 when rebuilding FPC (3.2.2 on win64) solves also the Currency * Currency ending in wrong values for large numbers.

Best of all worlds, uses 64bit double for Double calculations, and Extended for Extended data types. I didn't dig for other 87FPU functions.

Doesn't look to be penalizing in terms of speed.

Thanks.


PascalDragon

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Re: Why MaxDouble does not equal to MaxDouble?
« Reply #39 on: October 07, 2024, 09:22:36 pm »
3. One reason for sticking with 32-bit apps is that the Extended type and FPU are supported.

Then you also shouldn't use non-x86 processors, because the x86 family is the only one that supports 80-bit floating point (well, m68k supports it as well, but it has a slightly different format).

BrunoK

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Re: Why MaxDouble does not equal to MaxDouble?
« Reply #40 on: October 07, 2024, 09:50:55 pm »
3. One reason for sticking with 32-bit apps is that the Extended type and FPU are supported.

Then you also shouldn't use non-x86 processors, because the x86 family is the only one that supports 80-bit floating point (well, m68k supports it as well, but it has a slightly different format).
So you also should throw 80 bit float out or Linux x86_64 FPC.
Why dont you do it ?

PascalDragon

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Re: Why MaxDouble does not equal to MaxDouble?
« Reply #41 on: October 07, 2024, 10:00:05 pm »
Why dont you do it ?

Simple: Backwards compatibility.

BrunoK

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Re: Why MaxDouble does not equal to MaxDouble?
« Reply #42 on: October 07, 2024, 10:02:20 pm »

MarkMLl

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Re: Why MaxDouble does not equal to MaxDouble?
« Reply #43 on: October 07, 2024, 10:16:50 pm »
Now this is really rude. >:(

Thaddy told you he remembers there were some instructions that might interest you.

I suggest that "Go Forth and multiply", implying postfix notation, is not entirely in the spirit of a forum devoted to Pascal >:-)

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