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From: mitchalsup@aol.com (MitchAlsup1)
Newsgroups: comp.arch
Subject: Re: Split instruction and immediate stream
Date: Sun, 9 Mar 2025 19:23:04 +0000
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On Sun, 9 Mar 2025 12:03:22 +0000, Robert Finch wrote:

>>
> One thought I had a while ago using a similar technique to glyph's was
> to place constants at the beginning or the end of a cache line. Then the
> immediate base register is not needed. The relative offsets would be in
> terms of the current cache line. It has a couple of drawbacks though,
> one being the need to branch around the constant data; could be done by
> carefully maintaining the next fetch address. Another drawback is the
> code is repositionable only at cache-line boundaries. Might make
> assembling / linking code interesting.

If you put the constants at the end of the cache line, you will have
accessed the constants while decoding the instructions and you can
figure out when to jump to the next cache line without branching.