[FastTokenizer] Support FastTokenizer on Android (#3999)

* [FastTokenizer] Support FastTokenizer on Android * Update how_to_build_android.md * fix code style * fix code style * add copyright Co-authored-by: Zeyu Chen <[email protected]>
PaddlePaddle · Dec 4, 2022 · b07eed5 · b07eed5
1 parent d73ec67
commit b07eed5
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Showing 8 changed files with 266 additions and 7 deletions.
diff --git a/fast_tokenizer/CMakeLists.txt b/fast_tokenizer/CMakeLists.txt
@@ -1,3 +1,17 @@
+# Copyright (c) 2022 PaddlePaddle Authors. All Rights Reserved.
+#
+# 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.
+
 cmake_minimum_required(VERSION 3.10)
 
 project(tokenizers LANGUAGES CXX C VERSION 1.0)
@@ -103,8 +117,13 @@ endforeach()
 ELSE(WIN32)
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -O3 -fPIC")
     IF (NOT APPLE)
-        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -ldl -lpthread")
-    ENDIF()
+      set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -ldl")
+      IF (NOT ANDROID)
+        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -lpthread")
+      ELSE()
+        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Os")
+      ENDIF()
+    ENDIF()    
     set (PUBLIC_DEPEND_LIBS ${CMAKE_DL_LIBS})
 ENDIF(WIN32)
 

diff --git a/fast_tokenizer/cmake/external/gflags.cmake b/fast_tokenizer/cmake/external/gflags.cmake
@@ -29,6 +29,53 @@ ENDIF(WIN32)
 
 INCLUDE_DIRECTORIES(${GFLAGS_INCLUDE_DIR})
 
+IF(ANDROID)    
+set(CROSS_COMPILE_CMAKE_ARGS
+    "-DCMAKE_SYSTEM_NAME=${CMAKE_SYSTEM_NAME}"
+    "-DCMAKE_SYSTEM_VERSION=${CMAKE_SYSTEM_VERSION}"
+    "-DCMAKE_ANDROID_ARCH_ABI=${CMAKE_ANDROID_ARCH_ABI}"
+    "-DCMAKE_ANDROID_NDK=${CMAKE_ANDROID_NDK}"
+    "-DCMAKE_ANDROID_STL_TYPE=${CMAKE_ANDROID_STL_TYPE}"
+    "-DANDROID_ABI=${CMAKE_ANDROID_ARCH_ABI}"
+    "-DANDROID_TOOLCHAIN=${ANDROID_TOOLCHAIN}"
+    "-DANDROID_STL=${CMAKE_ANDROID_STL_TYPE}"
+    "-DCMAKE_SYSTEM_PROCESSOR=${CMAKE_SYSTEM_PROCESSOR}"
+    "-DCMAKE_TOOLCHAIN_FILE=${CMAKE_ANDROID_NDK}/build/cmake/android.toolchain.cmake"
+    "-DCMAKE_ANDROID_NDK_TOOLCHAIN_VERSION=${CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION}"
+    "-DANDROID_PLATFORM=android-${ANDROID_NATIVE_API_LEVEL}"
+    "-D__ANDROID_API__=${ANDROID_NATIVE_API_LEVEL}")
+
+ExternalProject_Add(
+    extern_gflags
+    ${EXTERNAL_PROJECT_LOG_ARGS}
+    ${SHALLOW_CLONE}
+    GIT_REPOSITORY  ${GFLAGS_REPOSITORY}
+    GIT_TAG         ${GFLAGS_TAG}
+    PREFIX          ${GFLAGS_PREFIX_DIR}
+    UPDATE_COMMAND  ""
+    BUILD_COMMAND   ${BUILD_COMMAND}
+    INSTALL_COMMAND ${INSTALL_COMMAND}
+    CMAKE_ARGS      ${CROSS_COMPILE_CMAKE_ARGS} 
+                    -DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}
+                    -DCMAKE_C_COMPILER=${CMAKE_C_COMPILER}
+                    -DCMAKE_CXX_FLAGS=${CMAKE_CXX_FLAGS}
+                    -DCMAKE_CXX_FLAGS_RELEASE=${CMAKE_CXX_FLAGS_RELEASE}
+                    -DCMAKE_CXX_FLAGS_DEBUG=${CMAKE_CXX_FLAGS_DEBUG}
+                    -DCMAKE_C_FLAGS=${CMAKE_C_FLAGS}
+                    -DCMAKE_C_FLAGS_DEBUG=${CMAKE_C_FLAGS_DEBUG}
+                    -DCMAKE_C_FLAGS_RELEASE=${CMAKE_C_FLAGS_RELEASE}
+                    -DBUILD_STATIC_LIBS=ON
+                    -DCMAKE_INSTALL_PREFIX=${GFLAGS_INSTALL_DIR}
+                    -DCMAKE_POSITION_INDEPENDENT_CODE=ON
+                    -DBUILD_TESTING=OFF
+                    -DCMAKE_BUILD_TYPE=${THIRD_PARTY_BUILD_TYPE}
+                    ${EXTERNAL_OPTIONAL_ARGS}
+    CMAKE_CACHE_ARGS -DCMAKE_INSTALL_PREFIX:PATH=${GFLAGS_INSTALL_DIR}
+                     -DCMAKE_POSITION_INDEPENDENT_CODE:BOOL=ON
+                     -DCMAKE_BUILD_TYPE:STRING=${THIRD_PARTY_BUILD_TYPE}
+    BUILD_BYPRODUCTS ${GFLAGS_LIBRARIES}
+)
+ELSE()
 ExternalProject_Add(
     extern_gflags
     ${EXTERNAL_PROJECT_LOG_ARGS}
@@ -58,6 +105,7 @@ ExternalProject_Add(
                      -DCMAKE_BUILD_TYPE:STRING=${THIRD_PARTY_BUILD_TYPE}
     BUILD_BYPRODUCTS ${GFLAGS_LIBRARIES}
 )
+ENDIF()
 
 ADD_LIBRARY(gflags STATIC IMPORTED GLOBAL)
 SET_PROPERTY(TARGET gflags PROPERTY IMPORTED_LOCATION ${GFLAGS_LIBRARIES})
@@ -70,4 +118,4 @@ if (WIN32)
   if (HAVE_SHLWAPI)
     set_property(GLOBAL PROPERTY OS_DEPENDENCY_MODULES shlwapi.lib)
   endif(HAVE_SHLWAPI)
-endif (WIN32)
+endif (WIN32)
diff --git a/fast_tokenizer/cmake/external/glog.cmake b/fast_tokenizer/cmake/external/glog.cmake
@@ -31,6 +31,54 @@ ENDIF(WIN32)
 
 INCLUDE_DIRECTORIES(${GLOG_INCLUDE_DIR})
 
+IF(ANDROID)    
+set(CROSS_COMPILE_CMAKE_ARGS
+    "-DCMAKE_SYSTEM_NAME=${CMAKE_SYSTEM_NAME}"
+    "-DCMAKE_SYSTEM_VERSION=${CMAKE_SYSTEM_VERSION}"
+    "-DCMAKE_ANDROID_ARCH_ABI=${CMAKE_ANDROID_ARCH_ABI}"
+    "-DCMAKE_ANDROID_NDK=${CMAKE_ANDROID_NDK}"
+    "-DCMAKE_ANDROID_STL_TYPE=${CMAKE_ANDROID_STL_TYPE}"
+    "-DANDROID_ABI=${CMAKE_ANDROID_ARCH_ABI}"
+    "-DANDROID_TOOLCHAIN=${ANDROID_TOOLCHAIN}"
+    "-DANDROID_STL=${CMAKE_ANDROID_STL_TYPE}"
+    "-DCMAKE_SYSTEM_PROCESSOR=${CMAKE_SYSTEM_PROCESSOR}"
+    "-DCMAKE_TOOLCHAIN_FILE=${CMAKE_ANDROID_NDK}/build/cmake/android.toolchain.cmake"
+    "-DCMAKE_ANDROID_NDK_TOOLCHAIN_VERSION=${CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION}"
+    "-DANDROID_PLATFORM=android-${ANDROID_NATIVE_API_LEVEL}"
+    "-D__ANDROID_API__=${ANDROID_NATIVE_API_LEVEL}")
+
+ExternalProject_Add(
+    extern_glog
+    ${EXTERNAL_PROJECT_LOG_ARGS}
+    ${SHALLOW_CLONE}
+    GIT_REPOSITORY  ${GLOG_REPOSITORY}
+    GIT_TAG         ${GLOG_TAG}
+    DEPENDS         gflags
+    PREFIX          ${GLOG_PREFIX_DIR}
+    UPDATE_COMMAND  ""
+    CMAKE_ARGS      ${CROSS_COMPILE_CMAKE_ARGS}
+                    -DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}
+                    -DCMAKE_C_COMPILER=${CMAKE_C_COMPILER}
+                    -DCMAKE_CXX_FLAGS=${GLOG_CMAKE_CXX_FLAGS}
+                    -DCMAKE_CXX_FLAGS_RELEASE=${CMAKE_CXX_FLAGS_RELEASE}
+                    -DCMAKE_CXX_FLAGS_DEBUG=${CMAKE_CXX_FLAGS_DEBUG}
+                    -DCMAKE_C_FLAGS=${CMAKE_C_FLAGS}
+                    -DCMAKE_C_FLAGS_DEBUG=${CMAKE_C_FLAGS_DEBUG}
+                    -DCMAKE_C_FLAGS_RELEASE=${CMAKE_C_FLAGS_RELEASE}
+                    -DCMAKE_INSTALL_PREFIX=${GLOG_INSTALL_DIR}
+                    -DCMAKE_INSTALL_LIBDIR=${GLOG_INSTALL_DIR}/lib
+                    -DCMAKE_POSITION_INDEPENDENT_CODE=ON
+                    -DWITH_GFLAGS=OFF
+                    -DBUILD_TESTING=OFF
+                    -DCMAKE_BUILD_TYPE=${THIRD_PARTY_BUILD_TYPE}
+                    ${EXTERNAL_OPTIONAL_ARGS}
+    CMAKE_CACHE_ARGS -DCMAKE_INSTALL_PREFIX:PATH=${GLOG_INSTALL_DIR}
+                     -DCMAKE_INSTALL_LIBDIR:PATH=${GLOG_INSTALL_DIR}/lib
+                     -DCMAKE_POSITION_INDEPENDENT_CODE:BOOL=ON
+                     -DCMAKE_BUILD_TYPE:STRING=${THIRD_PARTY_BUILD_TYPE}
+    BUILD_BYPRODUCTS ${GLOG_LIBRARIES}
+)
+ELSE()
 ExternalProject_Add(
     extern_glog
     ${EXTERNAL_PROJECT_LOG_ARGS}
@@ -61,8 +109,9 @@ ExternalProject_Add(
                      -DCMAKE_BUILD_TYPE:STRING=${THIRD_PARTY_BUILD_TYPE}
     BUILD_BYPRODUCTS ${GLOG_LIBRARIES}
 )
+ENDIF()
 
 ADD_LIBRARY(glog STATIC IMPORTED GLOBAL)
 SET_PROPERTY(TARGET glog PROPERTY IMPORTED_LOCATION ${GLOG_LIBRARIES})
 ADD_DEPENDENCIES(glog extern_glog gflags)
-LINK_LIBRARIES(glog)
+LINK_LIBRARIES(glog)
diff --git a/fast_tokenizer/cmake/external/icu.cmake b/fast_tokenizer/cmake/external/icu.cmake
@@ -16,7 +16,19 @@ include(ExternalProject)
 include (ByproductsICU)
 SET(ICU_PREFIX_DIR    ${THIRD_PARTY_PATH}/icu)
 SET(ICU_INSTALL_DIR   ${THIRD_PARTY_PATH}/install/icu)
-SET(ICU_REPOSITORY    ${GIT_URL}/unicode-org/icu.git)
+if(ANDROID)
+  set(ICU_URL_PREFIX "https://bj.bcebos.com/fastdeploy/test")
+  # check ABI, toolchain
+  if((NOT ANDROID_ABI MATCHES "armeabi-v7a") AND (NOT ANDROID_ABI MATCHES "arm64-v8a"))
+    message(FATAL_ERROR "FastTokenizer for Android only support armeabi-v7a, arm64-v8a now.")
+  endif()
+  if(NOT ANDROID_TOOLCHAIN MATCHES "clang")
+     message(FATAL_ERROR "Currently, only support clang toolchain while cross compiling FastTokenizer for Android, but found ${ANDROID_TOOLCHAIN}.")
+  endif()  
+  set(ICU_REPOSITORY ${ICU_URL_PREFIX}/icu-android-${ANDROID_ABI}.tgz)
+else()
+  SET(ICU_REPOSITORY    ${GIT_URL}/unicode-org/icu.git)
+endif()  
 SET(ICU_TAG           release-70-1)
 set(FIND_OR_BUILD_ICU_DIR ${CMAKE_CURRENT_LIST_DIR})
 
@@ -70,6 +82,23 @@ ExternalProject_Add(
         INSTALL_COMMAND make install prefix="" DESTDIR=${ICU_INSTALL_DIR} install
         BUILD_BYPRODUCTS ${ICU_LIBRARIES}
 )
+elseif(ANDROID)
+ExternalProject_Add(
+        extern_icu
+        ${EXTERNAL_PROJECT_LOG_ARGS}
+        ${SHALLOW_CLONE}
+        URL               ${ICU_REPOSITORY}
+        PREFIX            ${ICU_PREFIX_DIR}
+        CONFIGURE_COMMAND ""
+        UPDATE_COMMAND    ""
+        BUILD_COMMAND     ""
+        INSTALL_COMMAND
+          ${CMAKE_COMMAND} -E remove_directory ${ICU_INSTALL_DIR} &&
+          ${CMAKE_COMMAND} -E make_directory ${ICU_INSTALL_DIR} &&  
+          ${CMAKE_COMMAND} -E rename ${ICU_PREFIX_DIR}/src/extern_icu/lib/ ${ICU_INSTALL_DIR}/lib &&
+          ${CMAKE_COMMAND} -E copy_directory ${ICU_PREFIX_DIR}/src/extern_icu/include ${ICU_INSTALL_DIR}/include
+        BUILD_BYPRODUCTS ${ICU_LIBRARIES}
+)
 else()
 ExternalProject_Add(
         extern_icu

diff --git a/fast_tokenizer/cmake/external/re2.cmake b/fast_tokenizer/cmake/external/re2.cmake
@@ -24,17 +24,64 @@ IF(WIN32)
   add_definitions(-DRE2_STATIC)
 ELSEIF(APPLE)
   SET(RE2_LIBRARIES     "${RE2_INSTALL_DIR}/lib/libre2.a")
+ELSEIF(ANDROID)
+  SET(RE2_LIBRARIES     "${RE2_INSTALL_DIR}/lib/libre2.a")
 ELSE()
   IF(CMAKE_HOST_SYSTEM_PROCESSOR MATCHES "aarch64|arm64")
     SET(RE2_LIBRARIES     "${RE2_INSTALL_DIR}/lib/libre2.a")
   ELSE()
-    SET(RE2_LIBRARIES     "${RE2_INSTALL_DIR}/lib64/libre2.a")
+    file(READ "/etc/issue" ETC_ISSUE)
+    string(REGEX MATCH "Debian|Ubuntu" DIST ${ETC_ISSUE})
+    IF(DIST STREQUAL "Debian")
+      SET(RE2_LIBRARIES     "${RE2_INSTALL_DIR}/lib/libre2.a")
+    ELSEIF(DIST STREQUAL "Ubuntu")
+      SET(RE2_LIBRARIES     "${RE2_INSTALL_DIR}/lib/libre2.a")
+    ELSE()
+      SET(RE2_LIBRARIES     "${RE2_INSTALL_DIR}/lib64/libre2.a")
+    ENDIF()
   ENDIF()
 ENDIF()
 
 SET(RE2_INCLUDE_DIR ${RE2_INSTALL_DIR}/include)
 INCLUDE_DIRECTORIES(${RE2_INCLUDE_DIR})
 
+IF(ANDROID)    
+set(CROSS_COMPILE_CMAKE_ARGS
+    "-DCMAKE_SYSTEM_NAME=${CMAKE_SYSTEM_NAME}"
+    "-DCMAKE_SYSTEM_VERSION=${CMAKE_SYSTEM_VERSION}"
+    "-DCMAKE_ANDROID_ARCH_ABI=${CMAKE_ANDROID_ARCH_ABI}"
+    "-DCMAKE_ANDROID_NDK=${CMAKE_ANDROID_NDK}"
+    "-DCMAKE_ANDROID_STL_TYPE=${CMAKE_ANDROID_STL_TYPE}"
+    "-DANDROID_ABI=${CMAKE_ANDROID_ARCH_ABI}"
+    "-DANDROID_TOOLCHAIN=${ANDROID_TOOLCHAIN}"
+    "-DANDROID_STL=${CMAKE_ANDROID_STL_TYPE}"
+    "-DCMAKE_SYSTEM_PROCESSOR=${CMAKE_SYSTEM_PROCESSOR}"
+    "-DCMAKE_TOOLCHAIN_FILE=${CMAKE_ANDROID_NDK}/build/cmake/android.toolchain.cmake"
+    "-DCMAKE_ANDROID_NDK_TOOLCHAIN_VERSION=${CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION}"
+    "-DANDROID_PLATFORM=android-${ANDROID_NATIVE_API_LEVEL}"
+    "-D__ANDROID_API__=${ANDROID_NATIVE_API_LEVEL}")
+
+ExternalProject_Add(
+  extern_re2
+  ${EXTERNAL_PROJECT_LOG_ARGS}
+  ${SHALLOW_CLONE}
+  GIT_REPOSITORY        ${RE2_REPOSITORY}
+  GIT_TAG               ${RE2_TAG}
+  PREFIX                ${RE2_PREFIX_DIR}
+  UPDATE_COMMAND        ""
+  CMAKE_ARGS            ${CROSS_COMPILE_CMAKE_ARGS}
+                        -DCMAKE_CXX_FLAGS=${CMAKE_CXX_FLAGS}
+                        -DCMAKE_CXX_FLAGS_RELEASE=${CMAKE_CXX_FLAGS_RELEASE}
+                        -DCMAKE_CXX_FLAGS_DEBUG=${CMAKE_CXX_FLAGS_DEBUG}
+                        -DCMAKE_C_FLAGS=${CMAKE_C_FLAGS}
+                        -DCMAKE_C_FLAGS_DEBUG=${CMAKE_C_FLAGS_DEBUG}
+                        -DCMAKE_C_FLAGS_RELEASE=${CMAKE_C_FLAGS_RELEASE}
+                        -DCMAKE_INSTALL_PREFIX:PATH=${RE2_INSTALL_DIR}
+                        -DCMAKE_BUILD_TYPE:STRING=${THIRD_PARTY_BUILD_TYPE}
+                        -DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}
+  BUILD_BYPRODUCTS     ${RE2_LIBRARIES}
+)
+ELSE()
 ExternalProject_Add(
   extern_re2
   ${EXTERNAL_PROJECT_LOG_ARGS}
@@ -51,9 +98,11 @@ ExternalProject_Add(
                         -DCMAKE_C_FLAGS_RELEASE=${CMAKE_C_FLAGS_RELEASE}
                         -DCMAKE_INSTALL_PREFIX:PATH=${RE2_INSTALL_DIR}
                         -DCMAKE_BUILD_TYPE:STRING=${THIRD_PARTY_BUILD_TYPE}
+                        -DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}
   BUILD_BYPRODUCTS     ${RE2_LIBRARIES}
 )
+ENDIF()
 
 ADD_LIBRARY(re2 STATIC IMPORTED GLOBAL)
 SET_PROPERTY(TARGET re2 PROPERTY IMPORTED_LOCATION ${RE2_LIBRARIES})
-ADD_DEPENDENCIES(re2 extern_re2)
+ADD_DEPENDENCIES(re2 extern_re2)
diff --git a/fast_tokenizer/docs/compile/how_to_build_android.md b/fast_tokenizer/docs/compile/how_to_build_android.md
@@ -0,0 +1,29 @@
+# Android 编译
+
+## 环境依赖
+
+- cmake >= 3.10
+- NDK >= 20
+
+## 配置NDK
+```bash
+wget https://dl.google.com/android/repository/android-ndk-r20b-linux-x86_64.zip
+unzip android-ndk-r20b-linux-x86_64.zip # 会解压缩到 android-ndk-r20b 目录
+export NDK_ROOT=${PWD}/android-ndk-r20b
+```
+
+## 编译C++库方法
+
+```bash
+git clone https://github.com/PaddlePaddle/PaddleNLP.git
+cd PaddleNLP/fast_tokenizer
+mkdir build & cd build
+cmake .. -DCMAKE_TOOLCHAIN_FILE=$NDK_ROOT/build/cmake/android.toolchain.cmake -DANDROID_ABI="arm64-v8a" -DANDROID_NATIVE_API_LEVEL=android-21 -DANDROID_STL=c++_static -DWITH_TESTING=OFF -DWITH_PYTHON=OFF -DANDROID_TOOLCHAIN=clang
+make -j8
+```
+编译后的C++库在当前目录下的`cpp`目录下。可以选择使用strip减少库体积:
+```shell
+$NDK_ROOT/toolchains/llvm/prebuilt/linux-x86_64/aarch64-linux-android/bin/strip libcore_tokenizers.so
+```
+
+更多编译选项说明参考[编译指南](./README.md)
diff --git a/fast_tokenizer/run_build_android_armv7_lib.sh b/fast_tokenizer/run_build_android_armv7_lib.sh
@@ -0,0 +1,18 @@
+# Copyright (c) 2022 PaddlePaddle Authors. All Rights Reserved.
+#
+# 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.
+
+mkdir build_android_armeabi_v7a
+cd build_android_armeabi_v7a
+cmake .. -DCMAKE_TOOLCHAIN_FILE=$NDK_ROOT/build/cmake/android.toolchain.cmake -DANDROID_ABI="armeabi-v7a" -DANDROID_NATIVE_API_LEVEL=android-21 -DANDROID_STL=c++_static -DWITH_TESTING=OFF -DWITH_PYTHON=OFF -DANDROID_TOOLCHAIN=clang  
+make -j8
diff --git a/fast_tokenizer/run_build_android_armv8_lib.sh b/fast_tokenizer/run_build_android_armv8_lib.sh
@@ -0,0 +1,18 @@
+# Copyright (c) 2022 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+mkdir build_android_arm64_v8a
+cd build_android_arm64_v8a
+cmake .. -DCMAKE_TOOLCHAIN_FILE=$NDK_ROOT/build/cmake/android.toolchain.cmake -DANDROID_ABI="arm64-v8a" -DANDROID_NATIVE_API_LEVEL=android-21 -DANDROID_STL=c++_static -DWITH_TESTING=OFF -DWITH_PYTHON=OFF -DANDROID_TOOLCHAIN=clang  
+make -j8