onyx-lang / onyx

✨ The compiler and developer toolchain for Onyx
https://onyxlang.io
BSD 2-Clause "Simplified" License
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Feature: New memory layout #133

Closed brendanfh closed 7 months ago

brendanfh commented 8 months ago

This pull request alters the memory layout of a typical Onyx program, specifically how the stack operates. Up until this point, the stack grew up towards the maximum address, i.e. setting up the call frame involved adding to the stack pointer. This was sufficient, but as I am looking to the future of interoperating with other libraries compiled to WASM, I noticed that all other languages/compilers have the stack growing down towards 0. While this choice is largely arbitrary, it makes more sense to make Onyx conform to this memory model.

In short, the memory went from looking like this:

| globals / static data | stack -->   ...  |  heap -->  

To this:

| ...  <-- stack | globals / static data | heap -->

Aside from being compatible with other languages, this model has one great benefit: if the stack is overflowed, the program will crash, instead of blinding overwriting the heap and corrupting memory.