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From: Kragen Javier Sitaker <kragen@canonical.org>
Newsgroups: comp.lang.forth
Subject: Re: First result in riscv optimiser
Date: Fri, 04 Sep 2026 13:14:43 -0300
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anton@mips.complang.tuwien.ac.at (Anton Ertl) writes:
> (...) in general I don't think that full constant folding will trigger
> often, but partial constant folding (e.g., optimizing "5 -" into lit+
> with the immediate argument -5) is probably relatively frequent, and
> occasionally, constant folding works in cases where a much
> heavier-weight optimization would otherwise be needed.

This is contextual.  I have no doubt that you are correct in the case of
GForth, but in some compilers, constant folding is one of the most
important and frequently used optimizations.  But that’s because they’re
doing inlining and/or specialization, which create lots more constants
to fold, and dead-code elimination, which prunes conditionals that are
resolved at compile time by constant folding.

I don’t know enough about ciforth to guess how important it will be in
the ciforth context.

Kragen