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== Goal
A memory-safe language with a simple translator to x86 that can be feasibly written in x86.
== Definitions of terms
Memory-safe: it should be impossible to:
a) create a pointer out of arbitrary data, or
b) to access heap memory after it's been freed.
Simple: do all the work in a 2-pass translator:
Pass 1: check each instruction's types in isolation.
Pass 2: emit code for each instruction in isolation.
== types
int
char
(address _)
(array _ n)
(ref _)
addresses can't be saved to stack or global,
or included in compound types
or used across a call (to eliminate possibility of free)
<reg x> : (address T) <- advance <reg/mem> : (array T), <reg offset> : (index T)
arrays require a size
(ref array _) may not include a size
== open questions
Is argv an address?
Global variables are easiest to map to addresses.
Ideally we'd represent 'indirect' as a '*' and we could just count to make
sure that an instruction never has more than one '*'.
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