[docs] document how to bisect and how to use gdb for debugging jit aarch64 (#112)

Adds documents that can be made available in the future on the website about using debugging tools and how to properly bisect Git commits.
Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/112
Co-authored-by: Lizzie <lizzie@eden-emu.dev>
Co-committed-by: Lizzie <lizzie@eden-emu.dev>

docs/Development.md

@@ -0,0 +1,174 @@
+# 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)
+
+# Building speedup
+
+If you have an HDD, use ramdisk (build in RAM):
+```sh
+sudo mkdir /tmp/ramdisk
+sudo chmod 777 /tmp/ramdisk
+# about 10GB needed
+sudo mount -t tmpfs -o size=10G myramdisk /tmp/ramdisk
+cmake -B /tmp/ramdisk
+cmake --build /tmp/ramdisk -- -j32
+sudo umount /tmp/ramdisk
+```
+
+# 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
+
+- `mo <cmd>`: Monitor commands, `get info`, `get fastmem` and `get mappings` are available.
+- `detach`: Detach from remote (i.e restarting the emulator).
+- `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 older commits
+
+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
+cat > .gitmodules <<EOF
+[submodule "enet"]
+	path = externals/enet
+	url = https://github.com/lsalzman/enet.git
+[submodule "cubeb"]
+	path = externals/cubeb
+	url = https://github.com/mozilla/cubeb.git
+[submodule "dynarmic"]
+	path = externals/dynarmic
+	url = https://github.com/lioncash/dynarmic.git
+[submodule "libusb"]
+	path = externals/libusb/libusb
+	url = https://github.com/libusb/libusb.git
+[submodule "discord-rpc"]
+	path = externals/discord-rpc
+	url = https://github.com/yuzu-emu-mirror/discord-rpc.git
+[submodule "Vulkan-Headers"]
+	path = externals/Vulkan-Headers
+	url = https://github.com/KhronosGroup/Vulkan-Headers.git
+[submodule "sirit"]
+	path = externals/sirit
+	url = https://github.com/yuzu-emu-mirror/sirit.git
+[submodule "mbedtls"]
+	path = externals/mbedtls
+	url = https://github.com/yuzu-emu-mirror/mbedtls.git
+[submodule "xbyak"]
+	path = externals/xbyak
+	url = https://github.com/herumi/xbyak.git
+[submodule "opus"]
+	path = externals/opus
+	url = https://github.com/xiph/opus.git
+[submodule "SDL"]
+	path = externals/SDL
+	url = https://github.com/libsdl-org/SDL.git
+[submodule "cpp-httplib"]
+	path = externals/cpp-httplib
+	url = https://github.com/yhirose/cpp-httplib.git
+[submodule "ffmpeg"]
+	path = externals/ffmpeg/ffmpeg
+	url = https://github.com/FFmpeg/FFmpeg.git
+[submodule "vcpkg"]
+	path = externals/vcpkg
+	url = https://github.com/microsoft/vcpkg.git
+[submodule "cpp-jwt"]
+	path = externals/cpp-jwt
+	url = https://github.com/arun11299/cpp-jwt.git
+[submodule "libadrenotools"]
+	path = externals/libadrenotools
+	url = https://github.com/bylaws/libadrenotools.git
+[submodule "tzdb_to_nx"]
+	path = externals/nx_tzdb/tzdb_to_nx
+	url = https://github.com/lat9nq/tzdb_to_nx.git
+[submodule "VulkanMemoryAllocator"]
+	path = externals/VulkanMemoryAllocator
+	url = https://github.com/GPUOpen-LibrariesAndSDKs/VulkanMemoryAllocator.git
+[submodule "breakpad"]
+	path = externals/breakpad
+	url = https://github.com/yuzu-emu-mirror/breakpad.git
+[submodule "simpleini"]
+	path = externals/simpleini
+	url = https://github.com/brofield/simpleini.git
+[submodule "oaknut"]
+	path = externals/oaknut
+	url = https://github.com/merryhime/oaknut.git
+[submodule "Vulkan-Utility-Libraries"]
+	path = externals/Vulkan-Utility-Libraries
+	url = https://github.com/KhronosGroup/Vulkan-Utility-Libraries.git
+[submodule "oboe"]
+	path = externals/oboe
+	url = https://github.com/google/oboe.git
+[submodule "externals/boost-headers"]
+	path = externals/boost-headers
+	url = https://github.com/boostorg/headers.git
+EOF
+git submodule sync
+update_or_checkout () {
+    if [ $0 = 'externals/sirit' ] \
+    || [ $0 = 'externals/dynarmic' ] \
+    || [ $0 = 'externals/breakpad' ] \
+    || [ $0 = 'externals/discord-rpc' ] \
+    || [ $0 = 'externals/mbedtls' ]; then
+        [ -f $0/CMakeLists.txt ] || git submodule update --force --remote --init -- $0
+        echo $0 ':remote' && git submodule update --remote $0
+        exit
+    elif [ $0 = 'externals/nx_tzdb/tzdb_to_nx' ]; then
+        [ -f $0/CMakeLists.txt ] || git submodule update --force --remote --init -- $0
+        echo $0 ':remote' && git submodule update --remote $0
+    else
+        echo $0 ':update' && git submodule update --init $0 && exit
+        echo $0 ':remote' && git submodule update --remote $0 && exit
+        echo $0 ':failure'
+    fi
+}
+export -f update_or_checkout
+grep path .gitmodules | sed 's/.*= //' | xargs -n 1 -I {} bash -c 'update_or_checkout "$@"' {}
+# Fix for LLVM builds
+sed -i 's/src\/yuzu\/main.cpp/${CMAKE_SOURCE_DIR}\/src\/yuzu\/main.cpp/g' CMakeModules/FindLLVM.cmake
+# Only after cloning and everything - fixes issues with Zydis
+cat > externals/dynarmic/src/dynarmic/common/x64_disassemble.cpp <<EOF
+#include <cstddef>
+#include <vector>
+#include <string>
+namespace Dynarmic::Common {
+void DumpDisassembledX64(const void* ptr, size_t size) {}
+std::vector<std::string> DisassembleX64(const void* ptr, size_t size) { return {}; }
+}
+EOF
+```
+
+If having issues with older artifacts, then run `rm -r externals/dynarmic/build externals/dynarmic/externals externals/nx_tzdb/tzdb_to_nx/externals externals/sirit/externals`.
+
+Configuring CMake with `-DSIRIT_USE_SYSTEM_SPIRV_HEADERS=1 -DCMAKE_CXX_FLAGS="-Wno-error" -DCMAKE_C_FLAGS="-Wno-error -Wno-array-parameter -Wno-stringop-overflow"` is also recommended.
+