New function call/return helper opcodes

[Dentosal]

$is being the basis of jumps is something we should get rid of. I'd like to introduce two new opcodes:

• JMPA $reg imm : jump to absolute address in register plus immediate
• SRAJ $reta reg/imm store return address and jump to "function"

[MitchTurner]

https://translate.google.com/?sl=pl&tl=en&text=sraj&op=translate

[MitchTurner]

It sounds like this would optimize a lot of places where the compiler adds 3 opcodes, and this would replace those spots with 1. It would be a nice improvement to bytecode size.