CMake polishing

* Improve CPU features detection

  CMAKE_SYSTEM_PROCESSOR is pretty useless (e.g. when compiling with
  MSVC ARM64 toolchain and Ninja still returns system processor).

* Don't build src/utils targets by default

  Fix compilation for UWP platform.

* Add more Visual studio Git ignore patterns
* Autogenerate Doxygen docs

7 files changed, 61 insertions, 19 deletions

diff --git a/.gitignore b/.gitignore
index 88d097c2..8e73e13c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -79,6 +79,8 @@ oss-fuzz/fuzz-decoder
 oss-fuzz/fuzz-encoder
 
 /*[Bb]uild*/
+/out/
+CMakeSettings.json
 CMakeLists.txt.user
 CMakeCache.txt
 CMakeFiles
diff --git a/Makefile.am b/Makefile.am
index 33bc679e..7729c36f 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -43,6 +43,8 @@ EXTRA_DIST = \
 	flac-config.cmake.in \
 	cmake/FindOgg.cmake \
 	cmake/UseSystemExtensions.cmake \
+	cmake/CheckCPUArch.cmake \
+	cmake/CheckCPUArch.c.in \
 	COPYING.FDL \
 	COPYING.GPL \
 	COPYING.LGPL \
diff --git a/cmake/CheckCPUArch.c.in b/cmake/CheckCPUArch.c.in
new file mode 100644
index 00000000..54931394
--- /dev/null
+++ b/cmake/CheckCPUArch.c.in
@@ -0,0 +1,7 @@
+int main(void) {
+#if @CHECK_CPU_ARCH_DEFINES@
+    return 0;
+#else
+    fail
+#endif
+}
diff --git a/cmake/CheckCPUArch.cmake b/cmake/CheckCPUArch.cmake
new file mode 100644
index 00000000..95330b4b
--- /dev/null
+++ b/cmake/CheckCPUArch.cmake
@@ -0,0 +1,23 @@
+macro(_CHECK_CPU_ARCH ARCH ARCH_DEFINES VARIABLE)
+    if(NOT DEFINED HAVE_${VARIABLE})
+        message(STATUS "Check CPU architecture is ${ARCH}")
+        set(CHECK_CPU_ARCH_DEFINES ${ARCH_DEFINES})
+        configure_file(${PROJECT_SOURCE_DIR}/cmake/CheckCPUArch.c.in ${PROJECT_BINARY_DIR}/CMakeFiles/CMakeTmp/CheckCPUArch.c @ONLY)
+        try_compile(HAVE_${VARIABLE} "${PROJECT_BINARY_DIR}"
+            "${PROJECT_BINARY_DIR}/CMakeFiles/CMakeTmp/CheckCPUArch.c")
+        if(HAVE_${VARIABLE})
+            message(STATUS "Check CPU architecture is ${ARCH} - yes")
+            set(${VARIABLE} 1 CACHE INTERNAL "Result of CHECK_CPU_ARCH_X64" FORCE)
+        else ()
+            message(STATUS "Check CPU architecture is ${ARCH} - no")
+        endif()
+    endif ()
+endmacro(_CHECK_CPU_ARCH)
+
+macro(CHECK_CPU_ARCH_X64 VARIABLE)
+    _CHECK_CPU_ARCH(x64 "defined(__amd64__) || defined(__amd64) || defined(__x86_64__) || defined(__x86_64) || defined(_M_X64) || defined(_M_AMD64)" ${VARIABLE})
+endmacro(CHECK_CPU_ARCH_X64)
+
+macro(CHECK_CPU_ARCH_X86 VARIABLE)
+    _CHECK_CPU_ARCH(x86 "defined(__i386__) || defined(__i486__) || defined(__i586__) || defined(__i686__) ||defined( __i386) || defined(_M_IX86)" ${VARIABLE})
+endmacro(CHECK_CPU_ARCH_X86)
diff --git a/doc/CMakeLists.txt b/doc/CMakeLists.txt
index 9af88e4e..e0e33913 100644
--- a/doc/CMakeLists.txt
+++ b/doc/CMakeLists.txt
@@ -15,12 +15,20 @@ endif()
 set(DOXYGEN_HTML_FOOTER doxygen.footer.html)
 set(DOXYGEN_GENERATE_TAGFILE FLAC.tag)
 
-doxygen_add_docs(FLAC-doxygen
-    "${PROJECT_SOURCE_DIR}/include/FLAC"
-    "${PROJECT_SOURCE_DIR}/include/FLAC++")
+if(CMAKE_VERSION VERSION_LESS 3.12)
+    doxygen_add_docs(FLAC-doxygen
+        ALL
+        "${PROJECT_SOURCE_DIR}/include/FLAC"
+        "${PROJECT_SOURCE_DIR}/include/FLAC++")
+else()
+    doxygen_add_docs(FLAC-doxygen
+        "${PROJECT_SOURCE_DIR}/include/FLAC"
+        "${PROJECT_SOURCE_DIR}/include/FLAC++")
+
+    install(DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/html/"
+        DESTINATION "${CMAKE_INSTALL_DOCDIR}/html/api")
 
-install(DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/html/"
-    DESTINATION "${CMAKE_INSTALL_DOCDIR}/html/api")
+endif()
 
 install(FILES
     html/images/logo.svg
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index b3c9fcf5..bde3647b 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -2,6 +2,7 @@ cmake_minimum_required(VERSION 3.11)
 
 option(ENABLE_64_BIT_WORDS "Set FLAC__BYTES_PER_WORD to 8 (4 is the default)" OFF)
 option(WITH_XMMS "Build XMMS plugin" OFF)
+option(BUILD_UTILS "Build utils" OFF)
 
 add_subdirectory("libFLAC")
 if(BUILD_CXXLIBS)
@@ -17,7 +18,7 @@ if(BUILD_PROGRAMS)
     add_subdirectory("flac")
     add_subdirectory("metaflac")
 endif()
-if(BUILD_CXXLIBS)
+if(BUILD_UTILS)
     add_subdirectory(utils/flacdiff)
     if(WIN32)
         add_subdirectory(utils/flactimer)
diff --git a/src/libFLAC/CMakeLists.txt b/src/libFLAC/CMakeLists.txt
index cb5b2a63..44a3519d 100644
--- a/src/libFLAC/CMakeLists.txt
+++ b/src/libFLAC/CMakeLists.txt
@@ -1,7 +1,3 @@
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "[xX]86(_64)?|(AMD|amd)64|i[346]86")
-    option(WITH_AVX "Enable AVX, AVX2 optimizations" ON)
-endif()
-
 option(WITH_ASM "Use any assembly optimization routines" ON)
 
 check_include_file("cpuid.h" HAVE_CPUID_H)
@@ -10,14 +6,17 @@ check_include_file("sys/param.h" HAVE_SYS_PARAM_H)
 set(CMAKE_REQUIRED_LIBRARIES m)
 check_function_exists(lround HAVE_LROUND)
 
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "[xX]86_64|(AMD|amd)64")
-    if(CMAKE_SIZEOF_VOID_P EQUAL 4)
-        set(IA32 TRUE)
-    endif()
-    add_definitions(-DFLAC__CPU_X86_64 -DFLAC__ALIGN_MALLOC_DATA)
-elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "([xX]|i[346])86")
-    set(IA32 TRUE)
-    add_definitions(-DFLAC__CPU_IA32 -DFLAC__ALIGN_MALLOC_DATA)
+include(CheckCSourceCompiles)
+include(CheckCPUArch)
+
+check_cpu_arch_x64(FLAC__CPU_X86_64)
+if(NOT FLAC__CPU_X86_64)
+    check_cpu_arch_x86(FLAC__CPU_IA32)
+endif()
+
+if(FLAC__CPU_X86_64 OR FLAC__CPU_IA32)
+    set(FLAC__ALIGN_MALLOC_DATA 1)
+    option(WITH_AVX "Enable AVX, AVX2 optimizations" ON)
 endif()
 
 include(CheckLanguage)
@@ -31,7 +30,7 @@ if(NOT WITH_ASM)
     add_definitions(-DFLAC__NO_ASM)
 endif()
 
-if(IA32)
+if(FLAC__CPU_IA32)
     if(WITH_ASM AND CMAKE_ASM_NASM_COMPILER)
         add_subdirectory(ia32)
     endif()