MSVC: Add support for targeting ARM64EC

Modules/CMakePlatformId.h.in

@@ -116,6 +116,9 @@
 # if defined(_M_IA64)
 #  define ARCHITECTURE_ID "IA64"
 
+# elif defined(_M_ARM64EC)
+#  define ARCHITECTURE_ID "ARM64EC"
+
 # elif defined(_M_X64) || defined(_M_AMD64)
 #  define ARCHITECTURE_ID "x64"
 

Modules/Platform/Windows-MSVC.cmake

@@ -154,7 +154,9 @@ set(CMAKE_BUILD_TYPE_INIT Debug)
 # Compute an architecture family from the architecture id.
 foreach(lang C CXX)
   set(_MSVC_${lang}_ARCHITECTURE_FAMILY "${MSVC_${lang}_ARCHITECTURE_ID}")
-  if(_MSVC_${lang}_ARCHITECTURE_FAMILY MATCHES "^ARM64")
+  if(_MSVC_${lang}_ARCHITECTURE_FAMILY MATCHES "^ARM64EC")
+    set(_MSVC_${lang}_ARCHITECTURE_FAMILY "ARM64EC")
+  elseif(_MSVC_${lang}_ARCHITECTURE_FAMILY MATCHES "^ARM64")
     set(_MSVC_${lang}_ARCHITECTURE_FAMILY "ARM64")
   elseif(_MSVC_${lang}_ARCHITECTURE_FAMILY MATCHES "^ARM")
     set(_MSVC_${lang}_ARCHITECTURE_FAMILY "ARM")
@@ -224,7 +226,9 @@ elseif(WINDOWS_PHONE OR WINDOWS_STORE)
   endif()
 else()
   set(_PLATFORM_DEFINES "/DWIN32")
-
+  if((_MSVC_C_ARCHITECTURE_FAMILY STREQUAL "ARM64EC") OR (_MSVC_CXX_ARCHITECTURE_FAMILY STREQUAL "ARM64EC"))
+    set(_PLATFORM_DEFINES "${_PLATFORM_DEFINES} /D_AMD64_ /DAMD64 /D_ARM64EC_ /DARM64EC /D_ARM64EC_WORKAROUND_")
+  endif()
   if(_MSVC_C_ARCHITECTURE_FAMILY STREQUAL "ARM" OR _MSVC_CXX_ARCHITECTURE_FAMILY STREQUAL "ARM")
     set(CMAKE_C_STANDARD_LIBRARIES_INIT "kernel32.lib user32.lib")
   elseif(MSVC_VERSION GREATER 1310)
@@ -261,6 +265,8 @@ if(MSVC_C_ARCHITECTURE_ID)
     set(_MACHINE_ARCH_FLAG "/machine:THUMB")
   elseif(_MSVC_C_ARCHITECTURE_FAMILY STREQUAL "ARM64")
     set(_MACHINE_ARCH_FLAG "/machine:ARM64")
+  elseif(_MSVC_C_ARCHITECTURE_FAMILY STREQUAL "ARM64EC")
+    set(_MACHINE_ARCH_FLAG "/machine:ARM64EC")
   elseif(_MSVC_C_ARCHITECTURE_FAMILY STREQUAL "ARM")
     set(_MACHINE_ARCH_FLAG "/machine:ARM")
   else()
@@ -271,6 +277,8 @@ elseif(MSVC_CXX_ARCHITECTURE_ID)
     set(_MACHINE_ARCH_FLAG "/machine:THUMB")
   elseif(_MSVC_CXX_ARCHITECTURE_FAMILY STREQUAL "ARM64")
     set(_MACHINE_ARCH_FLAG "/machine:ARM64")
+  elseif(_MSVC_CXX_ARCHITECTURE_FAMILY STREQUAL "ARM64EC")
+    set(_MACHINE_ARCH_FLAG "/machine:ARM64EC")
   elseif(_MSVC_CXX_ARCHITECTURE_FAMILY STREQUAL "ARM")
     set(_MACHINE_ARCH_FLAG "/machine:ARM")
   else()
@@ -305,7 +313,11 @@ foreach(t EXE SHARED MODULE)
   string(APPEND CMAKE_${t}_LINKER_FLAGS_RELEASE_INIT " /INCREMENTAL:NO")
 endforeach()
 
-string(APPEND CMAKE_STATIC_LINKER_FLAGS_INIT " ${_MACHINE_ARCH_FLAG}")
+if((_MSVC_C_ARCHITECTURE_FAMILY STREQUAL "ARM64EC") OR (_MSVC_CXX_ARCHITECTURE_FAMILY STREQUAL "ARM64EC"))
+  string(APPEND CMAKE_STATIC_LINKER_FLAGS_INIT " /machine:ARM64X")
+else()
+  string(APPEND CMAKE_STATIC_LINKER_FLAGS_INIT " ${_MACHINE_ARCH_FLAG}")
+endif()
 unset(_MACHINE_ARCH_FLAG)
 
 cmake_policy(GET CMP0091 __WINDOWS_MSVC_CMP0091)

Source/cmGlobalVisualStudioVersionedGenerator.cxx

@@ -200,6 +200,7 @@ public:
     platforms.emplace_back("Win32");
     platforms.emplace_back("ARM");
     platforms.emplace_back("ARM64");
+    platforms.emplace_back("ARM64EC");
     return platforms;
   }
 

Templates/MSBuild/FlagTables/v142_Link.json

@@ -350,6 +350,13 @@
     "value": "MachineARM64",
     "flags": []
   },
+  {
+    "name": "TargetMachine",
+    "switch": "MACHINE:ARM64EC",
+    "comment": "MachineARM64EC",
+    "value": "MachineARM64EC",
+    "flags": []
+  },
   {
     "name": "TargetMachine",
     "switch": "MACHINE:EBC",

Templates/MSBuild/FlagTables/v14_LIB.json

@@ -41,6 +41,13 @@
     "value": "MachineARM64",
     "flags": []
   },
+  {
+    "name": "TargetMachine",
+    "switch": "MACHINE:ARM64X",
+    "comment": "MachineARM64X",
+    "value": "MachineARM64X",
+    "flags": []
+  },
   {
     "name": "TargetMachine",
     "switch": "MACHINE:EBC",