As a high level language programmer, I look forward to understanding my computer all the way down i.e. including the ISA which is not happening on amd64.
MIT 6.004 was one of my favorite classes. I think you can probably find it on OpenCourseWare. Over the course of a semester, you work your way up from very basic transistor physics to basic logic gates to a DEC Alpha AXP-inspired CPU (but 32-bit instead of 64-bit, the program counter is one of the numbered registers, and the high bit of the program counter determines if it's in kernel or userspace mode) that you've designed at the logic gate level. There are test suites that run in a simulator (jsim), where the kernel includes emulation for multiply and divide instructions in the illegal operation trap handler... so as long as you've correctly implemented the most basic instructions, you can run some fairly complicated software in emulation.
In the class, there were competitions for the highest benchmark scores (in emulation) and highest ratio of benchmark score to gate count (again, in emulation). The high performance implementations end up having 5 stage pipelines with bypass networks to avoid having to wait for intermediate results to hit the register file. I remember even having the carry logic in my ALU alternate the sense of the carry at every level up the tree in order to save one gate delay at each level. My year, I don't think anyone implemented register renaming, but I wouldn't put it past some students.
I would love to see 6.004 switch from Beta to RISC-V and also for the Stanford compilers class to switch from MIPS to RISC-V.
Some of my education in this is from a book called Inside the Machine which I really enjoyed. I noticed I was able to easily understand the earlier architectures but at some point they got really complex and I didn’t find it accessible. I took a look at amd64 and it was like.. haha no. I’m sure I could learn it if I was spending every day with that layer but I’m not.
From what I’ve seen of RISC I’m hopeful I can retain it even going long intervals without looking at it.
For understanding what's going on all the way down to the ISA level, I'd say something like a PIC microcontroller is even easier since they tend to have only around 50 instructions, though RISC-V has the advantage that it could scale all the way up to potentially desktop CPUs some day
Well, you could go buy and read Fundamentals of Semiconductor Fabrication (I did). This should give you understanding comparable to reading The C Programming Language. Yes, it is shallower understanding than what you would get by writing a C compiler yourself or working at TSMC, but it definitely is still understanding.
