Should pointers be 64-bit?

With the current 32-bit pointer width, raw physical pointers are unconvenient at best and open up a bunch of pitfalls at worst.

Technically, pointers should be 64-bit, at least when any physical addressing model is enabled.
This is problematic because of the preferred integer width of 32-bit in shaders, while Rust assumes usize in most APIs.

Is there any way we could switch to a 64-bit target without compromising performance?
For example

• Add optimization passes to convert usize -> u32 for logical ops
• Add a custom SPIR-V type for usize that somehow gets inferred late
• Customize core to add u32 indexing

On the other hand, physical pointers in shaders are somewhat niche, especially with more progress towards better bindless extension.

Start by reviewing the linked PR #237 and the issue's discussion of 32-bit pointers, physical addressing, shader integer widths, and Rust's usize APIs. Determine whether a 64-bit target can be supported without compromising logical-operation performance, and document a viable direction or the reasons it is not practical.