1 # How to Cross-Compile ArmNN on x86_64 for arm64
3 * [Introduction](#introduction)
4 * [Build and install Google's Protobuf library](#buildProtobuf)
5 * [Build Caffe for x86_64](#buildCaffe)
6 * [Cross-compiling ToolChain](#installCCT)
7 * [Build Boost library for arm64](#installBaarch)
8 * [Build Compute Library](#buildCL)
9 * [Build ArmNN](#buildANN)
10 * [Run Unit Tests](#unittests)
11 * [Troubleshooting and Errors](#troubleshooting)
14 #### <a name="introduction">Introduction</a>
15 These are the step by step instructions on Cross-Compiling ArmNN under an x86_64 system to target an Arm64 system. This build flow has been tested with Ubuntu 16.04.
16 The instructions show how to build the ArmNN core library and the Boost, Protobuf, Caffe and Compute Libraries necessary for compilation.
18 #### <a name="buildProtobuf">Build and install Google's Protobuf library</a>
20 * Get protobuf-all-3.5.1.tar.gz from here: https://github.com/protocolbuffers/protobuf/releases/tag/v3.5.1
23 tar -zxvf protobuf-all-3.5.1.tar.gz
26 * Build a native (x86_64) version of the protobuf libraries and compiler (protoc):
27 (Requires cUrl, autoconf, llibtool, and other build dependencies if not previously installed: sudo apt install curl autoconf libtool build-essential g++)
31 ../configure --prefix=$HOME/armnn-devenv/google/x86_64_pb_install
35 * Build the arm64 version of the protobuf libraries:
39 CC=aarch64-linux-gnu-gcc \
40 CXX=aarch64-linux-gnu-g++ \
41 ../configure --host=aarch64-linux \
42 --prefix=$HOME/armnn-devenv/google/arm64_pb_install \
43 --with-protoc=$HOME/armnn-devenv/google/x86_64_pb_install/bin/protoc
48 #### <a name="buildCaffe">Build Caffe for x86_64</a>
49 * Ubuntu 16.04 installation. These steps are taken from the full Caffe installation documentation at: http://caffe.berkeleyvision.org/install_apt.html
50 * Install dependencies:
52 sudo apt-get install libleveldb-dev libsnappy-dev libopencv-dev libhdf5-serial-dev
53 sudo apt-get install --no-install-recommends libboost-all-dev
54 sudo apt-get install libgflags-dev libgoogle-glog-dev liblmdb-dev
55 sudo apt-get install libopenblas-dev
56 sudo apt-get install libatlas-base-dev
58 * Download Caffe-Master from: https://github.com/BVLC/caffe
60 git clone https://github.com/BVLC/caffe.git
62 cp Makefile.config.example Makefile.config
64 * Adjust Makefile.config as necessary for your environment, for example:
69 #Add hdf5 and protobuf include and library directories (Replace $HOME with explicit /home/username dir):
70 INCLUDE_DIRS := $(PYTHON_INCLUDE) /usr/local/include /usr/include/hdf5/serial/ $HOME/armnn-devenv/google/x86_64_pb_install/include/
71 LIBRARY_DIRS := $(PYTHON_LIB) /usr/local/lib /usr/lib /usr/lib/x86_64-linux-gnu/hdf5/serial/ $HOME/armnn-devenv/google/x86_64_pb_install/lib/
75 export PATH=$HOME/armnn-devenv/google/x86_64_pb_install/bin/:$PATH
76 export LD_LIBRARY_PATH=$HOME/armnn-devenv/google/x86_64_pb_install/lib/:$LD_LIBRARY_PATH
78 * Compilation with Make:
84 These should all run without errors
85 * caffe.pb.h and caffe.pb.cc will be needed when building ArmNN's Caffe Parser
87 #### <a name="installCCT">Cross-compiling ToolChain</a>
88 * Install the standard cross-compilation libraries for arm64:
90 sudo apt install crossbuild-essential-arm64
92 #### <a name="installBaarch">Build Boost library for arm64</a>
93 * Build Boost library for arm64
94 Download Boost version 1.64 from http://www.boost.org/doc/libs/1_64_0/more/getting_started/unix-variants.html
95 Version 1.66 is not supported.
97 tar -zxvf boost_1_64_0.tar.gz
99 echo "using gcc : arm : aarch64-linux-gnu-g++ ;" > user_config.jam
100 ./bootstrap.sh --prefix=$HOME/armnn-devenv/boost_arm64_install
101 ./b2 install toolset=gcc-arm link=static cxxflags=-fPIC --with-filesystem --with-test --with-log --with-program_options -j32 --user-config=user_config.jam
104 #### <a name="buildCL">Build Compute Library</a>
105 * Building the Arm Compute Library:
107 git clone https://github.com/ARM-software/ComputeLibrary.git
109 scons arch=arm64-v8a neon=1 opencl=1 embed_kernels=1 extra_cxx_flags="-fPIC" -j8 internal_only=0
112 #### <a name="buildANN">Build ArmNN</a>
113 * Compile ArmNN for arm64:
115 git clone https://github.com/ARM-software/armnn.git
121 * Use CMake to configure your build environment, update the following script and run it from the armnn/build directory to set up the armNN build:
124 CXX=aarch64-linux-gnu-g++ \
125 CC=aarch64-linux-gnu-gcc \
127 -DARMCOMPUTE_ROOT=$HOME/armnn-devenv/ComputeLibrary \
128 -DARMCOMPUTE_BUILD_DIR=$HOME/armnn-devenv/ComputeLibrary/build/ \
129 -DBOOST_ROOT=$HOME/armnn-devenv/boost_arm64_install/ \
130 -DARMCOMPUTENEON=1 -DARMCOMPUTECL=1 \
131 -DCAFFE_GENERATED_SOURCES=$HOME/armnn-devenv/caffe/build/src \
132 -DBUILD_CAFFE_PARSER=1 \
133 -DPROTOBUF_ROOT=$HOME/armnn-devenv/google/x86_64_pb_install/ \
134 -DPROTOBUF_LIBRARY_DEBUG=$HOME/armnn-devenv/google/arm64_pb_install/lib/libprotobuf.so.15.0.1 \
135 -DPROTOBUF_LIBRARY_RELEASE=$HOME/armnn-devenv/google/arm64_pb_install/lib/libprotobuf.so.15.0.1
142 #### <a name="unittests">Run Unit Tests</a>
143 * Copy the build folder to an arm64 linux machine
144 * Copy the libprotobuf.so.15.0.1 library file to the build folder
145 * cd to the build folder on your arm64 machine and set your LD_LIBRARY_PATH to its current location:
148 export LD_LIBRARY_PATH=`pwd`
150 * Create a symbolic link to libprotobuf.so.15.0.1:
152 ln -s libprotobuf.so.15.0.1 ./libprotobuf.so.15
157 Running 567 test cases...
159 *** No errors detected
161 #### <a name="troubleshooting">Troubleshooting and Errors:</a>
162 #### Error adding symbols: File in wrong format
163 * When building armNN:
165 /usr/local/lib/libboost_log.a: error adding symbols: File in wrong format
166 collect2: error: ld returned 1 exit status
167 CMakeFiles/armnn.dir/build.make:4028: recipe for target 'libarmnn.so' failed
168 make[2]: *** [libarmnn.so] Error 1
169 CMakeFiles/Makefile2:105: recipe for target 'CMakeFiles/armnn.dir/all' failed
170 make[1]: *** [CMakeFiles/armnn.dir/all] Error 2
171 Makefile:127: recipe for target 'all' failed
172 make: *** [all] Error 2
174 * Boost libraries are not compiled for the correct architecture, try recompiling for arm64
176 #### Virtual memory exhausted
177 * When compiling the boost libraries:
179 virtual memory exhausted: Cannot allocate memory
181 * Not enough memory available to compile. Increase the amount of RAM or swap space available.
184 #### Unrecognized command line option '-m64'
185 * When compiling the boost libraries:
187 aarch64-linux-gnu-g++: error: unrecognized command line option ‘-m64’
189 * Clean the boost library directory before trying to build with a different architecture:
193 * It should show the following for arm64:
201 #### Missing libz.so.1
202 * When compiling armNN:
204 /usr/lib/gcc-cross/aarch64-linux-gnu/5/../../../../aarch64-linux-gnu/bin/ld: warning: libz.so.1, needed by /home/<username>/armNN/usr/lib64/libprotobuf.so.15.0.0, not found (try using -rpath or -rpath-link)
207 * Missing arm64 libraries for libz.so.1, these can be added by adding a second architecture to dpkg and explicitly installing them:
209 sudo dpkg --add-architecture arm64
210 sudo apt-get install zlib1g:arm64
214 * If apt-get update returns 404 errors for arm64 repos refer to section 5 below.
215 * Alternatively the missing arm64 version of libz.so.1 can be downloaded and installed from a .deb package here:
216 https://launchpad.net/ubuntu/wily/arm64/zlib1g/1:1.2.8.dfsg-2ubuntu4
218 sudo dpkg -i zlib1g_1.2.8.dfsg-2ubuntu4_arm64.deb
221 #### Unable to install arm64 packages after adding arm64 architecture
222 * Using sudo apt-get update should add all of the required repos for arm64 but if it does not or you are getting 404 errors the following instructions can be used to add the repos manually:
223 * From stackoverflow:
224 https://askubuntu.com/questions/430705/how-to-use-apt-get-to-download-multi-arch-library/430718
225 * Open /etc/apt/sources.list with your preferred text editor.
227 * Mark all the current (default) repos as \[arch=<current_os_arch>], e.g.
229 deb [arch=amd64] http://archive.ubuntu.com/ubuntu/ xenial main restricted
231 * Then add the following:
233 deb [arch=arm64] http://ports.ubuntu.com/ xenial main restricted
234 deb [arch=arm64] http://ports.ubuntu.com/ xenial-updates main restricted
235 deb [arch=arm64] http://ports.ubuntu.com/ xenial universe
236 deb [arch=arm64] http://ports.ubuntu.com/ xenial-updates universe
237 deb [arch=arm64] http://ports.ubuntu.com/ xenial multiverse
238 deb [arch=arm64] http://ports.ubuntu.com/ xenial-updates multiverse
239 deb [arch=arm64] http://ports.ubuntu.com/ xenial-backports main restricted universe multiverse
241 * Update and install again:
243 sudo apt-get install zlib1g:arm64
248 #### Undefined references to google::protobuf:: functions
249 * When compiling armNN there are multiple errors of the following type:
251 libarmnnCaffeParser.so: undefined reference to `google::protobuf:*
253 * Missing or out of date protobuf compilation libraries.
254 Use the command 'protoc --version' to check which version of protobuf is available (version 3.5.1 is required).
255 Follow the instructions above to install protobuf 3.5.1
256 Note this will require you to recompile Caffe for x86_64
259 #### Errors on strict-aliasing rules when compiling the Compute Library
260 * When compiling the Compute Library there are multiple errors on strict-aliasing rules:
262 cc1plus: error: unrecognized command line option ‘-Wno-implicit-fallthrough’ [-Werror]
264 * Add Werror=0 to the scons command:
266 scons arch=arm64-v8a neon=1 opencl=1 embed_kernels=1 extra_cxx_flags="-fPIC" -j8 internal_only=0 Werror=0