Merge pull request #8753 from RyuheiMori:fix-cpu-feature-detection-on-android

3rdparty/cpufeatures/CMakeLists.txt

+if(NOT ANDROID)
+  message("cpufeatures is ANDROID project")
+endif()
+
+set(CPUFEATURES_ROOT "${CMAKE_CURRENT_SOURCE_DIR}" CACHE PATH "Android cpufeatures project sources (for example, <android-ndk>/sources/android/cpufeatures)")
+
+set(CPUFEATURES_INCLUDE_DIRS ${CPUFEATURES_ROOT} CACHE INTERNAL "")
+set(CPUFEATURES_LIBRARIES cpufeatures CACHE INTERNAL "")
+
+if(NOT DEFINED CPUFEATURES_SOURCES)
+  set(CPUFEATURES_SOURCES ${CPUFEATURES_ROOT}/cpu-features.c ${CPUFEATURES_ROOT}/cpu-features.h)
+endif()
+
+include_directories(${CPUFEATURES_INCLUDE_DIRS})
+add_library(cpufeatures STATIC ${CPUFEATURES_SOURCES})
+
+set_target_properties(cpufeatures
+  PROPERTIES OUTPUT_NAME cpufeatures
+  DEBUG_POSTFIX "${OPENCV_DEBUG_POSTFIX}"
+  COMPILE_PDB_NAME cpufeatures
+  COMPILE_PDB_NAME_DEBUG "cpufeatures${OPENCV_DEBUG_POSTFIX}"
+  ARCHIVE_OUTPUT_DIRECTORY ${3P_LIBRARY_OUTPUT_PATH}
+)
+
+if(ENABLE_SOLUTION_FOLDERS)
+  set_target_properties(cpufeatures PROPERTIES FOLDER "3rdparty")
+endif()
+
+if(NOT BUILD_SHARED_LIBS)
+  ocv_install_target(cpufeatures EXPORT OpenCVModules ARCHIVE DESTINATION ${OPENCV_3P_LIB_INSTALL_PATH} COMPONENT dev)
+endif()

3rdparty/cpufeatures/LICENSE

+Copyright (C) 2016 The Android Open Source Project
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.

3rdparty/cpufeatures/README.md

+The Android NDK provides a small library named cpufeatures that your app can use at runtime to detect the target device's CPU family and the optional features it supports.
+It is designed to work as-is on all official Android platform versions.
+
+https://developer.android.com/ndk/guides/cpu-features.html

3rdparty/libwebp/cpu-features/cpu-features.h → 3rdparty/cpufeatures/cpu-features.h

@@ -33,21 +33,40 @@
 
 __BEGIN_DECLS
 
+/* A list of valid values returned by android_getCpuFamily().
+ * They describe the CPU Architecture of the current process.
+ */
 typedef enum {
     ANDROID_CPU_FAMILY_UNKNOWN = 0,
     ANDROID_CPU_FAMILY_ARM,
     ANDROID_CPU_FAMILY_X86,
     ANDROID_CPU_FAMILY_MIPS,
+    ANDROID_CPU_FAMILY_ARM64,
+    ANDROID_CPU_FAMILY_X86_64,
+    ANDROID_CPU_FAMILY_MIPS64,
 
     ANDROID_CPU_FAMILY_MAX  /* do not remove */
 
 } AndroidCpuFamily;
 
-/* Return family of the device's CPU */
-extern AndroidCpuFamily   android_getCpuFamily(void);
+/* Return the CPU family of the current process.
+ *
+ * Note that this matches the bitness of the current process. I.e. when
+ * running a 32-bit binary on a 64-bit capable CPU, this will return the
+ * 32-bit CPU family value.
+ */
+extern AndroidCpuFamily android_getCpuFamily(void);
+
+/* Return a bitmap describing a set of optional CPU features that are
+ * supported by the current device's CPU. The exact bit-flags returned
+ * depend on the value returned by android_getCpuFamily(). See the
+ * documentation for the ANDROID_CPU_*_FEATURE_* flags below for details.
+ */
+extern uint64_t android_getCpuFeatures(void);
 
-/* The list of feature flags for ARM CPUs that can be recognized by the
- * library. Value details are:
+/* The list of feature flags for ANDROID_CPU_FAMILY_ARM that can be
+ * recognized by the library (see note below for 64-bit ARM). Value details
+ * are:
  *
  *   VFPv2:
  *     CPU supports the VFPv2 instruction set. Many, but not all, ARMv6 CPUs
@@ -103,6 +122,27 @@ extern AndroidCpuFamily   android_getCpuFamily(void);
  *     ARM CPU. This is only available on a few XScale-based CPU designs
  *     sold by Marvell. Pretty rare in practice.
  *
+ *   AES:
+ *     CPU supports AES instructions. These instructions are only
+ *     available for 32-bit applications running on ARMv8 CPU.
+ *
+ *   CRC32:
+ *     CPU supports CRC32 instructions. These instructions are only
+ *     available for 32-bit applications running on ARMv8 CPU.
+ *
+ *   SHA2:
+ *     CPU supports SHA2 instructions. These instructions are only
+ *     available for 32-bit applications running on ARMv8 CPU.
+ *
+ *   SHA1:
+ *     CPU supports SHA1 instructions. These instructions are only
+ *     available for 32-bit applications running on ARMv8 CPU.
+ *
+ *   PMULL:
+ *     CPU supports 64-bit PMULL and PMULL2 instructions. These
+ *     instructions are only available for 32-bit applications
+ *     running on ARMv8 CPU.
+ *
  * If you want to tell the compiler to generate code that targets one of
  * the feature set above, you should probably use one of the following
  * flags (for more details, see technical note at the end of this file):
@@ -150,6 +190,13 @@ extern AndroidCpuFamily   android_getCpuFamily(void);
  *
  *   -mcpu=iwmmxt
  *     Allows the use of iWMMXt instrinsics with GCC.
+ *
+ * IMPORTANT NOTE: These flags should only be tested when
+ * android_getCpuFamily() returns ANDROID_CPU_FAMILY_ARM, i.e. this is a
+ * 32-bit process.
+ *
+ * When running a 64-bit ARM process on an ARMv8 CPU,
+ * android_getCpuFeatures() will return a different set of bitflags
  */
 enum {
     ANDROID_CPU_ARM_FEATURE_ARMv7       = (1 << 0),
@@ -164,18 +211,84 @@ enum {
     ANDROID_CPU_ARM_FEATURE_IDIV_ARM    = (1 << 9),
     ANDROID_CPU_ARM_FEATURE_IDIV_THUMB2 = (1 << 10),
     ANDROID_CPU_ARM_FEATURE_iWMMXt      = (1 << 11),
+    ANDROID_CPU_ARM_FEATURE_AES         = (1 << 12),
+    ANDROID_CPU_ARM_FEATURE_PMULL       = (1 << 13),
+    ANDROID_CPU_ARM_FEATURE_SHA1        = (1 << 14),
+    ANDROID_CPU_ARM_FEATURE_SHA2        = (1 << 15),
+    ANDROID_CPU_ARM_FEATURE_CRC32       = (1 << 16),
+};
+
+/* The bit flags corresponding to the output of android_getCpuFeatures()
+ * when android_getCpuFamily() returns ANDROID_CPU_FAMILY_ARM64. Value details
+ * are:
+ *
+ *   FP:
+ *     CPU has Floating-point unit.
+ *
+ *   ASIMD:
+ *     CPU has Advanced SIMD unit.
+ *
+ *   AES:
+ *     CPU supports AES instructions.
+ *
+ *   CRC32:
+ *     CPU supports CRC32 instructions.
+ *
+ *   SHA2:
+ *     CPU supports SHA2 instructions.
+ *
+ *   SHA1:
+ *     CPU supports SHA1 instructions.
+ *
+ *   PMULL:
+ *     CPU supports 64-bit PMULL and PMULL2 instructions.
+ */
+enum {
+    ANDROID_CPU_ARM64_FEATURE_FP      = (1 << 0),
+    ANDROID_CPU_ARM64_FEATURE_ASIMD   = (1 << 1),
+    ANDROID_CPU_ARM64_FEATURE_AES     = (1 << 2),
+    ANDROID_CPU_ARM64_FEATURE_PMULL   = (1 << 3),
+    ANDROID_CPU_ARM64_FEATURE_SHA1    = (1 << 4),
+    ANDROID_CPU_ARM64_FEATURE_SHA2    = (1 << 5),
+    ANDROID_CPU_ARM64_FEATURE_CRC32   = (1 << 6),
 };
 
+/* The bit flags corresponding to the output of android_getCpuFeatures()
+ * when android_getCpuFamily() returns ANDROID_CPU_FAMILY_X86 or
+ * ANDROID_CPU_FAMILY_X86_64.
+ */
 enum {
     ANDROID_CPU_X86_FEATURE_SSSE3  = (1 << 0),
     ANDROID_CPU_X86_FEATURE_POPCNT = (1 << 1),
     ANDROID_CPU_X86_FEATURE_MOVBE  = (1 << 2),
+    ANDROID_CPU_X86_FEATURE_SSE4_1 = (1 << 3),
+    ANDROID_CPU_X86_FEATURE_SSE4_2 = (1 << 4),
+    ANDROID_CPU_X86_FEATURE_AES_NI = (1 << 5),
+    ANDROID_CPU_X86_FEATURE_AVX =    (1 << 6),
+    ANDROID_CPU_X86_FEATURE_RDRAND = (1 << 7),
+    ANDROID_CPU_X86_FEATURE_AVX2 =   (1 << 8),
+    ANDROID_CPU_X86_FEATURE_SHA_NI = (1 << 9),
+};
+
+/* The bit flags corresponding to the output of android_getCpuFeatures()
+ * when android_getCpuFamily() returns ANDROID_CPU_FAMILY_MIPS
+ * or ANDROID_CPU_FAMILY_MIPS64.  Values are:
+ *
+ *   R6:
+ *     CPU executes MIPS Release 6 instructions natively, and
+ *     supports obsoleted R1..R5 instructions only via kernel traps.
+ *
+ *   MSA:
+ *     CPU supports Mips SIMD Architecture instructions.
+ */
+enum {
+    ANDROID_CPU_MIPS_FEATURE_R6    = (1 << 0),
+    ANDROID_CPU_MIPS_FEATURE_MSA   = (1 << 1),
 };
 
-extern uint64_t    android_getCpuFeatures(void);
 
 /* Return the number of CPU cores detected on this device. */
-extern int         android_getCpuCount(void);
+extern int android_getCpuCount(void);
 
 /* The following is used to force the CPU count and features
  * mask in sandboxed processes. Under 4.1 and higher, these processes
@@ -190,6 +303,21 @@ extern int         android_getCpuCount(void);
 extern int android_setCpu(int      cpu_count,
                           uint64_t cpu_features);
 
+#ifdef __arm__
+/* Retrieve the ARM 32-bit CPUID value from the kernel.
+ * Note that this cannot work on sandboxed processes under 4.1 and
+ * higher, unless you called android_setCpuArm() before.
+ */
+extern uint32_t android_getCpuIdArm(void);
+
+/* An ARM-specific variant of android_setCpu() that also allows you
+ * to set the ARM CPUID field.
+ */
+extern int android_setCpuArm(int      cpu_count,
+                             uint64_t cpu_features,
+                             uint32_t cpu_id);
+#endif
+
 __END_DECLS
 
 #endif /* CPU_FEATURES_H */

3rdparty/libwebp/CMakeLists.txt

@@ -5,7 +5,7 @@
 project(${WEBP_LIBRARY})
 
 ocv_include_directories(${CMAKE_CURRENT_SOURCE_DIR})
-ocv_include_directories("${CMAKE_CURRENT_SOURCE_DIR}/cpu-features")
+ocv_include_directories(${CPUFEATURES_INCLUDE_DIRS})
 
 file(GLOB lib_srcs dec/*.c demux/*.c dsp/*.c enc/*.c mux/*.c utils/*.c webp/*.c)
 file(GLOB lib_hdrs dec/*.h demux/*.h dsp/*.h enc/*.h mux/*.h utils/*.h webp/*.h)
@@ -19,13 +19,7 @@ if(ANDROID AND ARMEABI_V7A AND NOT NEON)
   endforeach()
 endif()
 
-file(GLOB cpuf_s cpu-features/*.c)
-file(GLOB cpuf_h cpu-features/*.h)
 
-if(ANDROID)
-  set(lib_srcs ${lib_srcs} ${cpuf_s})
-  set(lib_hdrs ${lib_hdrs} ${cpuf_h})
-endif()
 
 # ----------------------------------------------------------------------------------
 #         Define the library target:
@@ -34,6 +28,7 @@ endif()
 add_definitions(-DWEBP_USE_THREAD)
 
 add_library(${WEBP_LIBRARY} STATIC ${lib_srcs} ${lib_hdrs})
+target_link_libraries(${WEBP_LIBRARY} ${CPUFEATURES_LIBRARIES})
 
 if(UNIX)
   if(CMAKE_COMPILER_IS_GNUCXX OR CV_ICC)

CMakeLists.txt

@@ -98,6 +98,10 @@ if(POLICY CMP0042)
   cmake_policy(SET CMP0042 NEW)
 endif()
 
+if(POLICY CMP0046)
+  cmake_policy(SET CMP0046 OLD)
+endif()
+
 if(POLICY CMP0051)
   cmake_policy(SET CMP0051 NEW)
 endif()
@@ -574,6 +578,10 @@ endif()
 #  Detect 3rd-party libraries
 # ----------------------------------------------------------------------------
 
+if(ANDROID)
+   add_subdirectory(3rdparty/cpufeatures)
+endif()
+
 include(cmake/OpenCVFindLibsGrfmt.cmake)
 include(cmake/OpenCVFindLibsGUI.cmake)
 include(cmake/OpenCVFindLibsVideo.cmake)

modules/core/CMakeLists.txt

@@ -32,10 +32,10 @@ source_group("Src" FILES "${OPENCV_MODULE_opencv_core_BINARY_DIR}/version_string
 ocv_glob_module_sources(SOURCES "${OPENCV_MODULE_opencv_core_BINARY_DIR}/version_string.inc"
                         HEADERS ${lib_cuda_hdrs} ${lib_cuda_hdrs_detail})
 
-ocv_module_include_directories(${the_module} ${ZLIB_INCLUDE_DIRS} ${OPENCL_INCLUDE_DIRS})
+ocv_module_include_directories(${the_module} ${ZLIB_INCLUDE_DIRS} ${OPENCL_INCLUDE_DIRS} ${CPUFEATURES_INCLUDE_DIRS})
 ocv_create_module(${extra_libs})
 
-ocv_target_link_libraries(${the_module} ${ZLIB_LIBRARIES} "${OPENCL_LIBRARIES}" "${VA_LIBRARIES}" "${LAPACK_LIBRARIES}")
+ocv_target_link_libraries(${the_module} ${ZLIB_LIBRARIES} "${OPENCL_LIBRARIES}" "${VA_LIBRARIES}" "${LAPACK_LIBRARIES}" "${CPUFEATURES_LIBRARIES}")
 
 ocv_add_accuracy_tests()
 ocv_add_perf_tests()

modules/core/src/system.cpp

@@ -73,6 +73,10 @@ Mutex* __initialization_mutex_initializer = &getInitializationMutex();
 #endif
 #endif
 
+#if defined ANDROID
+#  include <cpu-features.h>
+#endif
+
 #if defined WIN32 || defined _WIN32 || defined WINCE
 #ifndef _WIN32_WINNT           // This is needed for the declaration of TryEnterCriticalSection in winbase.h with Visual Studio 2005 (and older?)
   #define _WIN32_WINNT 0x0400  // http://msdn.microsoft.com/en-us/library/ms686857(VS.85).aspx
@@ -441,10 +445,16 @@ struct HWFeatures
         CV_UNUSED(cpuid_data_ex);
     #endif // OPENCV_HAVE_X86_CPUID
 
-    #if defined ANDROID || defined __linux__
+    #if defined __ANDROID__ || defined __linux__
     #ifdef __aarch64__
         have[CV_CPU_NEON] = true;
         have[CV_CPU_FP16] = true;
+    #elif defined __arm__ && defined __ANDROID__
+        __android_log_print(ANDROID_LOG_INFO, "OpenCV", "calling android_getCpuFeatures() ...");
+        uint64_t features = android_getCpuFeatures();
+        __android_log_print(ANDROID_LOG_INFO, "OpenCV", "calling android_getCpuFeatures() ... Done (%llx)", features);
+        have[CV_CPU_NEON] = (features & ANDROID_CPU_ARM_FEATURE_NEON) != 0;
+        have[CV_CPU_FP16] = (features & ANDROID_CPU_ARM_FEATURE_VFP_FP16) != 0;
     #elif defined __arm__
         int cpufile = open("/proc/self/auxv", O_RDONLY);