[cmake] refactor: Use CPM over submodules (#143)

Transfers the majority of submodules and large externals to CPM, using source archives rather than full Git clones. Not only does this save massive amounts of clone and configure time, but dependencies are grabbed on-demand rather than being required by default. Additionally, CPM will (generally) automatically search for system dependencies, though certain dependencies have options to control this.

Testing shows gains ranging from 5x to 10x in terms of overall clone/configure time.

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/143
Reviewed-by: CamilleLaVey <camillelavey99@gmail.com>

src/dynarmic/externals/CMakeLists.txt

@@ -0,0 +1,116 @@
+include(CPM)
+
+# Always build externals as static libraries, even when dynarmic is built as shared
+if (BUILD_SHARED_LIBS)
+    set(BUILD_SHARED_LIBS OFF)
+    set(CMAKE_POSITION_INDEPENDENT_CODE ON)
+    set_property(DIRECTORY PROPERTY EXCLUDE_FROM_ALL ON)
+endif()
+
+# Allow options shadowing with normal variables when subproject use old cmake policy
+set(CMAKE_POLICY_DEFAULT_CMP0077 NEW)
+
+# Disable tests in all externals supporting the standard option name
+set(BUILD_TESTING OFF)
+
+# For libraries that already come with a CMakeLists file,
+# simply add the directory to that file as a subdirectory
+# to have CMake automatically recognize them.
+
+# biscuit
+
+if ("riscv" IN_LIST ARCHITECTURE)
+    add_subdirectory(biscuit)
+
+    CPMAddPackage(
+        NAME biscuit
+        VERSION 0.9.1
+        URL "https://github.com/lioncash/biscuit/archive/76b0be8dae.zip"
+        URL_HASH SHA512=47d55ed02d032d6cf3dc107c6c0a9aea686d5f25aefb81d1af91db027b6815bd5add1755505e19d76625feeb17aa2db6cd1668fe0dad2e6a411519bde6ca4489
+        CUSTOM_CACHE_KEY "76b0"
+    )
+endif()
+
+# catch
+
+# TODO(crueter): dedup
+if (NOT TARGET Catch2::Catch2WithMain)
+    if (DYNARMIC_TESTS)
+        find_package(Catch2 3.0.1 REQUIRED)
+    endif()
+endif()
+
+# fmt
+
+if (NOT TARGET fmt::fmt)
+    # fmtlib formatting library
+    set(FMT_INSTALL ON)
+    add_subdirectory(fmt)
+endif()
+
+# mcl
+CPMAddPackage(
+    NAME mcl
+    VERSION 0.1.12
+    URL "https://github.com/azahar-emu/mcl/archive/7b08d83418.zip"
+    URL_HASH SHA512=f943bac39c1879986decad7a442ff4288eaeca4a2907684c7914e115a55ecc43c2782ded85c0835763fe04e40d5c82220ce864423e489e648e408a84f54dc4f3
+    OPTIONS
+        "MCL_INSTALL ON"
+    CUSTOM_CACHE_KEY "7b08"
+)
+
+# oaknut
+
+# if (NOT TARGET merry::oaknut)
+#     if ("arm64" IN_LIST ARCHITECTURE)
+#         add_subdirectory(oaknut)
+#     elseif (DYNARMIC_TESTS)
+#         add_subdirectory(oaknut EXCLUDE_FROM_ALL)
+#     endif()
+# endif()
+
+# unordered_dense
+
+CPMAddPackage(
+    NAME unordered_dense
+    URL "https://github.com/Lizzie841/unordered_dense/archive/e59d30b7b1.zip"
+    URL_HASH SHA512=71eff7bd9ba4b9226967bacd56a8ff000946f8813167cb5664bb01e96fb79e4e220684d824fe9c59c4d1cc98c606f13aff05b7940a1ed8ab3c95d6974ee34fa0
+    FIND_PACKAGE_ARGUMENTS "CONFIG"
+    OPTIONS
+        "UNORDERED_DENSE_INSTALL ON"
+    CUSTOM_CACHE_KEY "e59d"
+)
+
+# xbyak
+# uncomment if in an independent repo
+
+# if (NOT TARGET xbyak::xbyak)
+#     if ("x86_64" IN_LIST ARCHITECTURE)
+#         add_subdirectory(xbyak)
+#     endif()
+# endif()
+
+# zydis
+
+if ("x86_64" IN_LIST ARCHITECTURE)
+    CPMAddPackage(
+        NAME Zycore
+        URL "https://github.com/zyantific/zycore-c/archive/75a36c45ae.zip"
+        URL_HASH SHA512=15aa399f39713e042c4345bc3175c82f14dca849fde2a21d4f591f62c43e227b70d868d8bb86beb5f4eb68b1d6bd3792cdd638acf89009e787e3d10ee7401924
+        CUSTOM_CACHE_KEY "75a3"
+    )
+
+    CPMAddPackage(
+        NAME Zydis
+        VERSION 4
+        URL "https://github.com/zyantific/zydis/archive/c2d2bab025.zip"
+        URL_HASH SHA512=7b48f213ff7aab2926f8c9c65195959143bebbfb2b9a25051ffd8b8b0f1baf1670d9739781de674577d955925f91ac89376e16b476a03828c84e2fd765d45020
+        OPTIONS
+            "ZYDIS_BUILD_TOOLS OFF"
+            "ZYDIS_BUILD_EXAMPLES OFF"
+            "ZYDIS_BUILD_DOXYGEN OFF"
+            "ZYAN_ZYCORE_PATH ${Zycore_SOURCE_DIR}"
+            "CMAKE_DISABLE_FIND_PACKAGE_Doxygen ON"
+        CUSTOM_CACHE_KEY "c2d2"
+    )
+endif()