Greetings! I am actively working on porting x64 code to Apple Silicon now that the time is nigh and part of the fundamentals of our software is a coroutine library for handling cooperative multitasking of GUI operations on the main thread. I was hoping to get the locations of the stack pointer and frame pointer in jmp_buf so, after setjmp() can redirect them to the primary handling routines in our coroutine library that handles the cooperative scheduling (which replaced and ported the old classic MP routines) which worked for PowerPC, i386 and x64. Any thoughts on where in the jmp_buf these might be located? I didn't see anything in the XNU open source. Any advice would be much obliged instead of having to dive in and re-implement these routines in assembly myself!

Previously I had developed software using SMI eye trackers, both screen mounted and their mobile glasses, for unique therapeutic and physiology applications. Sadly, after SMI was bought by Apple, their hardware and software have been taken off the market and now it is very difficult to get secondhand-market systems. The Apple Vision Pro integrates the SMI hardware. While I can use ARKit to get gaze position, I do not see a way to access information that was previously made accessible on the SMI hardware, particularly: dwell time and pupil diameter information. I am hopeful (or asking) to see that if a user has a properly set up Optic ID and would opt-in if, either on the present or a future version of visionOS, it might be possible to get access to the data streams for dwell times and pupil diameter. Pupil diameter is particularly important as it is a very good physiological measure of how much stress a person is encountering, which is critical to some of the therapeutic applications that formerly we used SMI hardware. Any ideas, or, if this is not possible, proposing this to the visionOS team would be appreciated!

So, as we found out from WWDC, the migration to Apple Silicon is inevitable. Does anyone have a good recommendation for a replacement for Macintosh Common Lisp on Apple Silicon? I was using it back in the MPW days and struggling to keep the Lisp code working, but Apple Silicon has thrown a money wrench at it! Thanks in advance for any advice on any available Apple Silicon Lisp development tools!