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[Caml-list] The tag bit
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Date: 2004-08-12 (14:55)
From: Florian Hars <hars@b...>
Subject: Re: [Caml-list] The tag bit
Bauer, Christoph wrote:
> Isn't it possible to divide the memory in blocks of 33 (65 on 64 bit 
> machines) Words and the first Word contains all the tag bits?

Good idea, but lets go the whole way: I always thougth the decision to have 
eight bits to a byte instead of nine most unfortunate. Why don't we just add a 
bit to all our bytes, we could express so much more per byte? Just imagine the 
possibilities in I18N:  UTF-18 would need considerably less plane shifting that 

(On a more serious note: You propose to turn the tag bit into a tag long word, 
requiring two memory acesses instead of one and blowing up the storage 
requriments for ints and pointers by a factor of two, which will slow down 
about everything. You can get more or less the same effects now without any 
change to the compiler by using Int32.)

Yours, Florian.

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