local variable optimizations

[zack-bitcoin]

Another thing we could consider doing is optimizing accessing of variables who's pointers are offset from a value in the r-stack.

In a function, I use some contiguous available memory to store the local variables, and the root location is stored on the top of the r-stack.
So accessing the 3rd input of a function looks like 'r@ 2 + @'
I grab the pointer from the r-stack, add 2 to it so we are now pointing to the 3rd input, and then fetch it.

loading a value into the 3rd input of a function looks like 'r@ 2 + !'

So I am thinking we can add opcodes for access and setting the first 8 values

r@0 -> 'r@ @'
r!0 -> 'r@ !'
r@1 -> 'r@ 1 + @'
r!2 -> 'r@ 2 + !'

Currently we are using 8 opcodes to access or update a local variable. 5 opcodes to encode the integer, and 3 more opcodes to tell what we are doing.
By teaching the chalang VM these 16 new commands, we could get it down to 1 opcode for the first 8 local variables.
8 inputs is more than how many you need in the majority of function definitions.

[zack-bitcoin]

Maybe it is better to make r@ 2 + be the word, without the @ or ! at the end.