support clang compile on arm

CMakeLists.txt

@@ -42,7 +42,17 @@ if(LITE_WITH_LIGHT_WEIGHT_FRAMEWORK)
         message(FATAL_ERROR "ARM_TARGET_ARCH_ABI must be in one of ${ARM_TARGET_ARCH_ABI_LIST}")
     endif()
 
-    message(STATUS "Lite ARM Compile ${ARM_TARGET_OS} with ${ARM_TARGET_ARCH_ABI}")
+    # check arch abi
+    if(NOT DEFINED ARM_TARGET_LANG)
+        set(ARM_TARGET_LANG "clang" CACHE STRING "Choose ARM Target Language")
+    endif()
+    set(ARM_TARGET_LANG_LIST "gcc" "clang")
+    set_property(CACHE ARM_TARGET_LANG PROPERTY STRINGS ${ARM_TARGET_LANG_LIST})
+    if (NOT ARM_TARGET_LANG IN_LIST ARM_TARGET_LANG_LIST)
+        message(FATAL_ERROR "ARM_TARGET_LANG must be in one of ${ARM_TARGET_LANG_LIST}")
+    endif()
+
+    message(STATUS "Lite ARM Compile ${ARM_TARGET_OS} with ${ARM_TARGET_ARCH_ABI} ${ARM_TARGET_LANG}")
     include(cross_compiling/host)
     include(cross_compiling/armlinux)
     include(cross_compiling/android)
@@ -158,6 +168,9 @@ include_directories("${PADDLE_SOURCE_DIR}")
 # for mobile
 if (WITH_LITE AND LITE_WITH_LIGHT_WEIGHT_FRAMEWORK)
     message(STATUS "Building the mobile framework")
+    if (ANDROID)
+        include(cross_compiling/findar)
+    endif()
     # include the necessary thirdparty dependencies
     include(external/gflags)    # download, build, install gflags
     include(external/glog)      # download, build, install glog

cmake/cross_compiling/android.cmake

@@ -31,7 +31,7 @@ if(NOT DEFINED ANDROID_API_LEVEL)
 endif()
 
 if(NOT DEFINED ANDROID_STL_TYPE)
-    set(ANDROID_STL_TYPE "c++_static" CACHE STRING "stl type")
+    set(ANDROID_STL_TYPE "c++_static" CACHE STRING "stl type") # can also use shared
 endif()
 
 if(ARM_TARGET_ARCH_ABI STREQUAL "armv7hf")
@@ -71,8 +71,31 @@ if (NOT ANDROID_STL_TYPE IN_LIST ANDROID_STL_TYPE_LITS)
     message(FATAL_ERROR "ANDROID_STL_TYPE must be in one of ${ANDROID_STL_TYPE_LITS}")
 endif()
 
+if(ARM_TARGET_LANG STREQUAL "gcc")
+    # gcc do not need set lang
+    set(ARM_TARGET_LANG "")
+endif()
+
 set(CMAKE_SYSTEM_NAME Android)
 set(CMAKE_SYSTEM_VERSION ${ANDROID_API_LEVEL})
 set(CMAKE_ANDROID_ARCH_ABI ${ANDROID_ARCH_ABI})
 set(CMAKE_ANDROID_NDK ${ANDROID_NDK})
+set(CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION ${ARM_TARGET_LANG})
 set(CMAKE_ANDROID_STL_TYPE ${ANDROID_STL_TYPE})
+
+if (ARM_TARGET_LANG STREQUAL "clang")
+    if(ARM_TARGET_ARCH_ABI STREQUAL "armv8")
+        set(triple aarch64-v8a-linux-android)
+    elseif(ARM_TARGET_ARCH_ABI STREQUAL "armv7")
+        set(triple arm-v7a-linux-android)
+    else()
+        message(FATAL_ERROR "Clang do not support this ${ARM_TARGET_ARCH_ABI}, use armv8 or armv7")
+    endif()
+
+    set(CMAKE_C_COMPILER clang)
+    set(CMAKE_C_COMPILER_TARGET ${triple})
+    set(CMAKE_CXX_COMPILER clang++)
+    set(CMAKE_CXX_COMPILER_TARGET ${triple})
+
+    message(STATUS "CMAKE_CXX_COMPILER_TARGET: ${CMAKE_CXX_COMPILER_TARGET}")
+endif()

cmake/cross_compiling/findar.cmake

+# Copyright (c) 2019 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.
+
+if(NOT ARM_TARGET_LANG STREQUAL "clang")
+    # only clang need find ar tool
+    return()
+endif()
+
+if(NOT EXISTS "${CMAKE_CXX_COMPILER}")
+    message(ERROR "Can not find CMAKE_CXX_COMPILER ${CMAKE_CXX_COMPILER}")
+endif()
+
+get_filename_component(AR_PATH ${CMAKE_CXX_COMPILER} PATH)
+
+find_file(AR_TOOL NAMES llvm-ar PATHS ${AR_PATH})
+
+if(NOT AR_TOOL)
+    message(ERROR "Failed to find AR_TOOL in ${AR_PATH}")
+else()
+    set(CMAKE_AR ${AR_TOOL})
+    message(STATUS "Found CMAKE_AR : " ${CMAKE_AR})
+endif()

cmake/external/gflags.cmake

@@ -40,7 +40,8 @@ if(ANDROID)
                     "-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}")
+                    "-DCMAKE_ANDROID_STL_TYPE=${CMAKE_ANDROID_STL_TYPE}"
+                    "-DCMAKE_ANDROID_NDK_TOOLCHAIN_VERSION=${CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION}"            )
 endif()
 
 ExternalProject_Add(

cmake/external/glog.cmake

@@ -46,7 +46,8 @@ if(ANDROID)
                     "-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}")
+                    "-DCMAKE_ANDROID_STL_TYPE=${CMAKE_ANDROID_STL_TYPE}"
+                    "-DCMAKE_ANDROID_NDK_TOOLCHAIN_VERSION=${CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION}")
 endif()
 
 ExternalProject_Add(

cmake/external/gtest.cmake

@@ -58,7 +58,9 @@ IF(WITH_TESTING OR (WITH_DISTRIBUTE AND NOT WITH_GRPC))
             "-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}")
+            "-DCMAKE_ANDROID_STL_TYPE=${CMAKE_ANDROID_STL_TYPE}"
+            "-DCMAKE_ANDROID_NDK_TOOLCHAIN_VERSION=${CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION}"
+            )
     endif()
 
     ExternalProject_Add(

cmake/external/protobuf.cmake

@@ -199,6 +199,7 @@ FUNCTION(build_protobuf TARGET_NAME BUILD_FOR_HOST)
             "-DCMAKE_ANDROID_ARCH_ABI=${CMAKE_ANDROID_ARCH_ABI}"
             "-DCMAKE_ANDROID_NDK=${CMAKE_ANDROID_NDK}"
             "-DCMAKE_ANDROID_STL_TYPE=${CMAKE_ANDROID_STL_TYPE}"
+            "-DCMAKE_ANDROID_NDK_TOOLCHAIN_VERSION=${CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION}"
             "-DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}"
             "-DCMAKE_C_COMPILER=${CMAKE_C_COMPILER}"
             "-DCMAKE_C_FLAGS=${CMAKE_C_FLAGS}"

paddle/fluid/lite/core/CMakeLists.txt

 if (WITH_TESTING)
-    cc_library(lite_gtest_main SRCS lite_gtest_main.cc DEPS gtest)
+    cc_library(lite_gtest_main SRCS lite_gtest_main.cc DEPS gtest gflags)
 endif()
 lite_cc_library(target_wrapper_lite SRCS target_wrapper.cc
   DEPS target_wrapper_host

paddle/fluid/lite/tools/build.sh

@@ -57,6 +57,7 @@ function check_style {
 function cmake_arm {
     # $1: ARM_TARGET_OS in "android" , "armlinux"
     # $2: ARM_TARGET_ARCH_ABI in "armv8", "armv7" ,"armv7hf"
+    # $3: ARM_TARGET_LANG in "gcc" "clang"
     cmake .. \
         -DWITH_GPU=OFF \
         -DWITH_MKL=OFF \
@@ -66,7 +67,7 @@ function cmake_arm {
         -DLITE_WITH_ARM=ON \
         -DLITE_WITH_LIGHT_WEIGHT_FRAMEWORK=ON \
         -DWITH_TESTING=ON \
-        -DARM_TARGET_OS=$1 -DARM_TARGET_ARCH_ABI=$2
+        -DARM_TARGET_OS=$1 -DARM_TARGET_ARCH_ABI=$2 -DARM_TARGET_LANG=$3
 }
 
 function build_single {
@@ -125,31 +126,36 @@ function test_arm_android {
 function build_test_arm {
     # 1. Build goes first
     cur_dir=$(pwd)
-    for os in "android" "armlinux" ; do
-        for abi in "armv8" "armv7" "armv7hf"; do 
-            # TODO(hongming): enable compile armv7 and armv7hf on armlinux
-            if [[ ${abi} == "armv7hf" ]]; then
-                echo "armv7hf is not supported on both android and armlinux yet"
+    for lang in "gcc" "clang"; do
+        for os in "android" "armlinux" ; do
+            if [[ ${os} == "armlinux" && ${lang} == "clang" ]]; then
                 continue
             fi
-            
-            # TODO(hongming): enable armv7 on armlinux
-            if [[ ${os} == "armlinux" && ${abi} == "armv7" ]]; then
-                echo "armv7 is not supported on armlinux yet"
-                continue
-            fi
-
-            if [[ ${os} == "android" && ${abi} == "armv7hf" ]]; then
-                echo "android do not need armv7hf"
-                continue
-            fi
-
-            build_dir=$cur_dir/build.lite.${os}.${abi}
-            mkdir -p $build_dir
-            cd $build_dir
-
-            cmake_arm ${os} ${abi}
-            build $TESTS_FILE
+            for abi in "armv8" "armv7" "armv7hf"; do 
+                # TODO(hongming): enable compile armv7 and armv7hf on armlinux
+                if [[ ${abi} == "armv7hf" ]]; then
+                    echo "armv7hf is not supported on both android and armlinux yet"
+                    continue
+                fi
+                
+                # TODO(hongming): enable armv7 on armlinux
+                if [[ ${os} == "armlinux" && ${abi} == "armv7" ]]; then
+                    echo "armv7 is not supported on armlinux yet"
+                    continue
+                fi
+
+                if [[ ${os} == "android" && ${abi} == "armv7hf" ]]; then
+                    echo "android do not need armv7hf"
+                    continue
+                fi
+
+                build_dir=$cur_dir/build.lite.${os}.${abi}.${lang}
+                mkdir -p $build_dir
+                cd $build_dir
+
+                cmake_arm ${os} ${abi} ${lang}
+                build $TESTS_FILE
+            done
         done
     done
 
@@ -168,26 +174,28 @@ function build_test_arm {
     sleep 1m
 
     # now can only test android.
-    for abi in "armv8" "armv7" ; do
-        # TODO(yuanshuai): enable armv7 on android
-        if [[ ${abi} == "armv7" ]]; then
-            continue
-        fi
-
-        build_dir=$cur_dir/build.lite.android.${abi}
-        cd $build_dir
-
-        local port=
-        if [[ ${abi} == "armv7" ]]; then
-            port=${port_armv7}
-        fi
-
-        if [[ ${abi} == "armv8" ]]; then
-            port=${port_armv8}
-        fi
-        echo "test file: ${TESTS_FILE}"
-        for _test in $(cat $TESTS_FILE); do
-            test_arm_android $_test $port
+    for lang in "gcc" "clang"; do
+        for abi in "armv8" "armv7" ; do
+            # TODO(yuanshuai): enable armv7 on android
+            if [[ ${abi} == "armv7" ]]; then
+                continue
+            fi
+
+            build_dir=$cur_dir/build.lite.android.${abi}.${lang}
+            cd $build_dir
+
+            local port=
+            if [[ ${abi} == "armv7" ]]; then
+                port=${port_armv7}
+            fi
+
+            if [[ ${abi} == "armv8" ]]; then
+                port=${port_armv8}
+            fi
+            echo "test file: ${TESTS_FILE}"
+            for _test in $(cat $TESTS_FILE); do
+                test_arm_android $_test $port
+            done
         done
     done
 

paddle/fluid/lite/tools/mobile_readme.md

@@ -26,6 +26,7 @@ $ git checkout incubate/lite
         - "armv8", 等效于 "arm64"。 default值为这个。
         - "armv7hf", 等效于使用`eabihf`且`-march=armv7-a -mfloat-abi=hard -mfpu=neon-vfpv4 `。
         - "armv7", 等效于使用`eabi`且`-march=armv7-a -mfloat-abi=softfp -mfpu=neon-vfpv4`。
+- `ARM_TARGET_LANG` 代表目标编译的语言， 默认为gcc，支持 gcc和clang两种。
 
 ### 编译