> because a VL-ISA can use https://en.wikipedia.org/wiki/Huffman_coding where the structure of the
> Huffman tree is based on expected execution traces and/or on real-world execution traces.

In practice, instructions tend to follow the classic distribution.

About half of them are comprised of the popular basics: add, shift,
branch, load, store, etc. Plus one or two outliers, often vector or
cisc, due to some popular algorithm. You will see 2-4 dozen total,
adding up to that first half.

The second half is then comprised of everything else: one long tail
of tiny bits and pieces, simply adding up. Got two thousand total?
You will see hundreds of them over time.

So yes, Huffman will help for the super popular ones, but overall it
really won't: the numbers simply are against you.

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:-)