[docs] document how to bisect and how to use gdb for debugging jit aarch64

docs/Development.md

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+# Development
+
+* **Windows**: [Windows Building Guide](./docs/build/Windows.md)
+* **Linux**: [Linux Building Guide](./docs/build/Linux.md)
+* **Android**: [Android Building Guide](./docs/build/Android.md)
+* **Solaris**: [Solaris Building Guide](./docs/build/Solaris.md)
+* **FreeBSD**: [FreeBSD Building Guide](./docs/build/FreeBSD.md)
+* **macOS**: [macOS Building Guide](./docs/build/macOS.md)
+
+# How to test JIT
+
+## gdb
+
+Run `./build/bin/eden-cli -c <path to your config file (see logs where you run eden normally to see where it is)> -d -g <path to game>`
+
+Then hook up an aarch64-gdb (use `yay aarch64-gdb` or `sudo pkg in arch64-gdb` to install)
+Then type `target remote localhost:1234` and type `c` (for continue) - and then if it crashes just do a `bt` (backtrace) and `layout asm`.
+
+### gdb cheatsheet
+
+- `c`: Continue
+- `p <expr>`: Print variable, `p/x <expr>` for hexadecimal.
+- `r`: Run
+- `bt`: Print backtrace
+- `info threads`: Print all active threads
+- `thread <number>`: Switch to the given thread (see `info threads`)
+- `layout asm`: Display in assembly mode (TUI)
+- `si`: Step assembly instruction
+- `s` or `step`: Step over LINE OF CODE (not assembly)
+- `display <expr>`: Display variable each step.
+- `n`: Next (skips over call frame of a function)
+- `frame <number>`: Switches to the given frame (from `bt`)
+- `br <expr>`: Set breakpoint at `<expr>`.
+- `delete`: Deletes all breakpoints.
+- `catch throw`: Breakpoint at throw. Can also use `br __cxa_throw`
+
+Expressions can be `variable_names` or `1234` (numbers) or `*var` (dereference of a pointer) or `*(1 + var)` (computed expression).
+
+For more information type `info gdb` and read [the man page](https://man7.org/linux/man-pages/man1/gdb.1.html).
+
+# Bisecting
+
+Each commit should be buildable (independently) so bisecting is easier. See [git-bisect](https://git-scm.com/docs/git-bisect) for more information.
+
+## Notes
+
+Since going into the past can be tricky (especially due to the dependencies from the project being lost thru time). This should "restore" the URLs for the respective submodules.
+
+```sh
+#!/bin/sh
+rm .gitmodules
+wget -O .gitmodules https://git.eden-emu.dev/eden-emu/eden/raw/branch/master/.gitmodules
+git submodule update --init --recursive
+```
+
+If you're not on Linux I'm sorry for you. Git gud.