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From: Keean Schupke <keean.schupke@googlemail.com>
Newsgroups: comp.lang.ada
Subject: Re: Efficient Sequential Access to Arrays
Date: Sun, 15 Jul 2012 14:08:37 -0700 (PDT)
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Date: 2012-07-15T14:08:37-07:00
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On Sunday, 15 July 2012 22:05:05 UTC+1, (unknown)  wrote:
> &gt; as the use of Indexes was too slow. An example of this is lets say we are a=
> &gt; ccessing element 5 from array A &quot;A(5)&quot; this requires a multiplication to ac=
> &gt; cess (base_address + index * record_size). To access the neighbour A(6) als=
>   Can you reasonably pad the element size to a power of two so the
> multiplication can be replaced by a shift?  It would be interesting to see
> the result, in various hardware contexts.

Actually in my actual use case the record is 32 bytes, and it does use a shift right by 5 instead of a multiply, but this is still 10k simulations per second slower that the pointer arithmetic version.


Cheers,
Keean.