cmake: Detect powerpc architecture

CMakeLists.txt

@@ -372,7 +372,7 @@ dep_option(SDL_SSE                 "Use SSE assembly routines" ON "SDL_ASSEMBLY;
 dep_option(SDL_SSE2                "Use SSE2 assembly routines" ON "SDL_ASSEMBLY;SDL_CPU_X86 OR SDL_CPU_X64" OFF)
 dep_option(SDL_SSE3                "Use SSE3 assembly routines" ON "SDL_ASSEMBLY;SDL_CPU_X86 OR SDL_CPU_X64" OFF)
 dep_option(SDL_MMX                 "Use MMX assembly routines" ON "SDL_ASSEMBLY;SDL_CPU_X86 OR SDL_CPU_X64" OFF)
-dep_option(SDL_ALTIVEC             "Use Altivec assembly routines" ON "SDL_ASSEMBLY" OFF)
+dep_option(SDL_ALTIVEC             "Use Altivec assembly routines" ON "SDL_ASSEMBLY;SDL_CPU_POWERPC32 OR SDL_CPU_POWERPC64" OFF)
 dep_option(SDL_ARMSIMD             "Use SIMD assembly blitters on ARM" OFF "SDL_ASSEMBLY;SDL_CPU_ARM32" OFF)
 dep_option(SDL_ARMNEON             "Use NEON assembly blitters on ARM" OFF "SDL_ASSEMBLY;SDL_CPU_ARM32" OFF)
 dep_option(SDL_LSX                 "Use LSX assembly routines" ON "SDL_ASSEMBLY;SDL_CPU_LOONGARCH64" OFF)

cmake/CheckCPUArchitecture.cmake

@@ -36,9 +36,13 @@ function(check_cpu_architecture ARCH VARIABLE)
     _internal_check_cpu_architecture("defined(__loongarch64)" loongarch64 ${VARIABLE})
   elseif(ARCH STREQUAL "emscripten")
     _internal_check_cpu_architecture("defined(__EMSCRIPTEN__)" emscripten ${VARIABLE})
+  elseif(ARCH STREQUAL "powerpc32")
+    _internal_check_cpu_architecture("defined(__PPC__) || defined(__powerpc__)" powerpc32 ${VARIABLE})
+  elseif(ARCH STREQUAL "powerpc64")
+    _internal_check_cpu_architecture("defined(__PPC64__) || defined(__powerpc64__)" powerpc64 ${VARIABLE})
   else()
     message(WARNING "Unknown CPU architectures (${ARCH}).")
-    set(${VARIABLE} FALSE)
+    set("${VARIABLE}" FALSE)
   endif()
   set("${VARIABLE}" "${${VARIABLE}}" PARENT_SCOPE)
 endfunction()

cmake/sdlplatform.cmake

@@ -78,7 +78,7 @@ function(SDL_DetectCPUArchitecture)
     endforeach()
   endif()
 
-  set(sdl_known_archs x86 x64 arm32 arm64 loongarch64 emscripten)
+  set(sdl_known_archs x64 x86 arm64 arm32 emscripten powerpc32 powerpc64 loongarch64)
   if(NOT sdl_cpu_names)
     set(found FALSE)
     foreach(sdl_known_arch ${sdl_known_archs})