Merge pull request #2811 from martin-frbg/issue2806

Make NO_AVX512 option override the AVX512 compile test in CMAKE builds as well

cmake/system.cmake

@@ -110,6 +110,11 @@ if (NO_AVX2)
   set(GETARCH_FLAGS "${GETARCH_FLAGS} -DNO_AVX2")
 endif ()
 
+if (NO_AVX512)
+  message(STATUS "Disabling Advanced Vector Extensions 512 (AVX512).")
+  set(GETARCH_FLAGS "${GETARCH_FLAGS} -DNO_AVX512")
+endif ()
+
 if (CMAKE_BUILD_TYPE STREQUAL "Debug")
   set(GETARCH_FLAGS "${GETARCH_FLAGS} ${CMAKE_C_FLAGS_DEBUG}")
 endif ()

cmake/system_check.cmake

@@ -109,6 +109,7 @@ else()
 endif()
 
 if (X86_64 OR X86)
+if (NOT NO_AVX512)
   file(WRITE ${PROJECT_BINARY_DIR}/avx512.c "#include <immintrin.h>\n\nint main(void){ __asm__ volatile(\"vbroadcastss -4 * 4(%rsi), %zmm2\"); }")
 execute_process(COMMAND ${CMAKE_C_COMPILER} -march=skylake-avx512 -c -v -o ${PROJECT_BINARY_DIR}/avx512.o ${PROJECT_BINARY_DIR}/avx512.c OUTPUT_QUIET ERROR_QUIET RESULT_VARIABLE NO_AVX512)
 if (NO_AVX512 EQUAL 1)
@@ -116,6 +117,7 @@ set (CCOMMON_OPT "${CCOMMON_OPT} -DNO_AVX512")
 endif()
   file(REMOVE "avx512.c" "avx512.o")
 endif()
+endif()
 
 include(CheckIncludeFile)
 CHECK_INCLUDE_FILE("stdatomic.h" HAVE_C11)