From 52a9af3dca0c1e7b5e3007967e2ee0042a704f8b Mon Sep 17 00:00:00 2001
From: MerryMage <MerryMage@users.noreply.github.com>
Date: Thu, 11 Jun 2020 13:15:13 +0100
Subject: [PATCH] CMakeLists: Rework architecture detection

* Also only enable xybak/vixl on appropriate architectures
---
 CMakeLists.txt                        |  7 ----
 CMakeModules/DetectArchitecture.cmake | 54 +++++++++++++++++++++++----
 externals/CMakeLists.txt              |  6 ++-
 src/CMakeLists.txt                    |  2 +-
 4 files changed, 52 insertions(+), 17 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index cf67fb7f..e51b764a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -107,13 +107,6 @@ endif()
 
 # Arch detection
 include(DetectArchitecture)
-if (MSVC)
-    detect_architecture("_M_AMD64" x86_64)
-    detect_architecture("_M_ARM64" Aarch64)
-else()
-    detect_architecture("__x86_64__" x86_64)
-    detect_architecture("__aarch64__" Aarch64)
-endif()
 if (NOT DEFINED ARCHITECTURE)
     message(FATAL_ERROR "Unsupported architecture encountered. Ending CMake generation.")
 endif()
diff --git a/CMakeModules/DetectArchitecture.cmake b/CMakeModules/DetectArchitecture.cmake
index e984c6b8..ba6679cd 100644
--- a/CMakeModules/DetectArchitecture.cmake
+++ b/CMakeModules/DetectArchitecture.cmake
@@ -1,16 +1,56 @@
 include(CheckSymbolExists)
+
 function(detect_architecture symbol arch)
     if (NOT DEFINED ARCHITECTURE)
-        set(CMAKE_REQUIRED_QUIET 1)
-        check_symbol_exists("${symbol}" "" ARCHITECTURE_${arch})
+        set(CMAKE_REQUIRED_QUIET YES)
+        check_symbol_exists("${symbol}" "" DETECT_ARCHITECTURE_${arch})
         unset(CMAKE_REQUIRED_QUIET)
 
-        # The output variable needs to be unique across invocations otherwise
-        # CMake's crazy scope rules will keep it defined
-        if (ARCHITECTURE_${arch})
+        if (DETECT_ARCHITECTURE_${arch})
             set(ARCHITECTURE "${arch}" PARENT_SCOPE)
-            set(ARCHITECTURE_${arch} 1 PARENT_SCOPE)
-            add_definitions(-DARCHITECTURE_${arch}=1)
         endif()
+
+        unset(DETECT_ARCHITECTURE_${arch} CACHE)
     endif()
 endfunction()
+
+detect_architecture("__ARM64__" arm64)
+detect_architecture("__aarch64__" arm64)
+detect_architecture("_M_ARM64" arm64)
+
+detect_architecture("__arm__" arm)
+detect_architecture("__TARGET_ARCH_ARM" arm)
+detect_architecture("_M_ARM" arm)
+
+detect_architecture("__x86_64" x86_64)
+detect_architecture("__x86_64__" x86_64)
+detect_architecture("__amd64" x86_64)
+detect_architecture("_M_X64" x86_64)
+
+detect_architecture("__i386" x86)
+detect_architecture("__i386__" x86)
+detect_architecture("_M_IX86" x86)
+
+detect_architecture("__ia64" ia64)
+detect_architecture("__ia64__" ia64)
+detect_architecture("_M_IA64" ia64)
+
+detect_architecture("__mips" mips)
+detect_architecture("__mips__" mips)
+detect_architecture("_M_MRX000" mips)
+
+detect_architecture("__ppc64__" ppc64)
+detect_architecture("__powerpc64__" ppc64)
+
+detect_architecture("__ppc__" ppc)
+detect_architecture("__ppc" ppc)
+detect_architecture("__powerpc__" ppc)
+detect_architecture("_ARCH_COM" ppc)
+detect_architecture("_ARCH_PWR" ppc)
+detect_architecture("_ARCH_PPC" ppc)
+detect_architecture("_M_MPPC" ppc)
+detect_architecture("_M_PPC" ppc)
+
+detect_architecture("__riscv" riscv)
+
+detect_architecture("__EMSCRIPTEN__" wasm)
diff --git a/externals/CMakeLists.txt b/externals/CMakeLists.txt
index 3fb20a51..e5bbb936 100644
--- a/externals/CMakeLists.txt
+++ b/externals/CMakeLists.txt
@@ -27,12 +27,14 @@ target_include_directories(robin_map SYSTEM INTERFACE "$<BUILD_INTERFACE:${CMAKE
 
 # vixl
 
-add_subdirectory(vixl)
+if (ARCHITECTURE STREQUAL "arm64")
+    add_subdirectory(vixl)
+endif()
 
 # xbyak
 
 if (NOT TARGET xbyak)
-    if (ARCHITECTURE_x86 OR ARCHITECTURE_x86_64)
+    if (ARCHITECTURE STREQUAL "x86" OR ARCHITECTURE STREQUAL "x86_64")
         add_library(xbyak INTERFACE)
         target_include_directories(xbyak SYSTEM INTERFACE ${CMAKE_CURRENT_SOURCE_DIR}/xbyak/xbyak)
         target_compile_definitions(xbyak INTERFACE XBYAK_NO_OP_NAMES)
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 6e36979d..4f29030c 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -250,7 +250,7 @@ if ("A64" IN_LIST DYNARMIC_FRONTENDS)
     )
 endif()
 
-if (ARCHITECTURE_x86_64)
+if (ARCHITECTURE STREQUAL "x86_64")
     target_sources(dynarmic PRIVATE
         backend/x64/abi.cpp
         backend/x64/abi.h