TaggedArrays (Proposal)

[Mark Roos]

Hi Rémi,  you mention
And now the trick, there is a nice way (several in fact) to explain to 
the JIT
that even if the bytecode contains tests, if the variable contains 
effectively an int,
it's a good idea to remove them.

Ok,  in Smalltalk there are some methods which are usually integer ops
so its easy to determine vars that are likely integer.  I have slots in 
the stack reserved for just this idea.

So if I have a pair of slots A and B where A would be the integer from and 
B the reference.
Would I test B to be null and if so do an integer op on A?

So plese point me at the bytecode tricks that make the test go away.

regards
mark

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