2017/02/07

12:17

Thinking about it, JITExecutableBuilder can be merged into the class stream because the class stream just forwards everything to it anyway. This would reduce the number of classes and indirection.

12:50

I wonder if my stack allocation should be exact before-hand, or after the fact. It really does not matter, but I suppose it depends on the ABI. For example if I setup the stack beforehand then it is possible that the kernel can just plop a new stack right on top of the current stack. Maybe during the middle of execution of this code, it can virtually enter a new method. If the stack of the current method is outside of the stack bounds then it is possible the kernel would clobber the stack and destroy it if such events occur. Also, programs like GDB possibly operate in this matter, by having it where a new stack is temporarily overlaid on the current one.

13:21

I suppose a first thing I can do is perform no initial stack caching at all and just do it in a completely naive way. When I do implement stack caching though it should not require a rewrite of the code generation parts of the JIT because the machine code parts would be standalone using simple move logic and such.

15:38

I wonder if I should have flattened pointers that are only limited to a 32-bit address space. It would save some things when it comes to 64-bit for objects.

15:42

It would be too complicated, in most cases any system with a 64-bit address space will be using 64-bit registers. So I only need to consider the integer values of a smaller size. I would also have to make sure the OS only allocates in a given range so I can mask it in place. This would mean a single 4GiB pool of memory. Using bit shifting can be used, but then there is the block alignment. So it is pretty pointless and complexicated.