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Re: 64-bit ints and non-capable hardware

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Bryan C. Warnock
October 21, 2002 16:36
Re: 64-bit ints and non-capable hardware
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On Mon, 2002-10-21 at 15:11, Dan Sugalski wrote:
> Okay, I'm about ready to just bite the bullet and declare that 
> INTVALs have to be 64 bit integers.

Which INTVALs?  INTVAL, IMHAOSBRPO[1], is overused internally.
I see little relative performance and size damage if INTVAL is made 64
bits and relegated only to user-space math as long as the internals
(pointer-tracking, sizes, offsets, etc) are left as native.  You can
check and cast when numbers cross over.  OTOH, converting all of the
internals to 64-bit is probably not such a good idea.

Of course, I registers are probably being used for both uses completely
independent of each other.  

Or did I miss the point on wherefore 64-bit?

> Does anyone know of a platform that has neither native nor emulated 
> 64 bit integers? (One we're likely to run on, rather)

If it has neither, the internals shouldn't be affected, although
user-space values will be.  But you can convert to BigInt at 32 bits
vice 64.  (Assuming that's still the plan.)

[1] In My Humble And Oft-Stated But Rarely Patching Opinion  ;)

Bryan C. Warnock

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