Merge iOS and Pi changes into 0.9 branch (#2857)

* Updated iOS settings (#2694)

* Added linker options to armv7 in iOS makefile

* Updated Eigen version in Xcode iOS examples

* Updated iOS link flags

* Fixes for Raspberry Pi compilation (#2701)

* Added linker options to armv7 in iOS makefile

* Updated Eigen version in Xcode iOS examples

* Updated iOS link flags

* Added support for Raspberry Pi

* Updated Pi documentation and Eigen version in makefile (#2743)

* Updated Pi compilation documentation

* Updated Eigen version in makefile

* Updated documentation link

* Updated Pi documentation

* Updated Pi build settings

* Fix for build issue #2742; (#2749)

(1) Additionally added linking against pthread for linux machines

* Missing space; (#2762)

(1) bash file check will fail without the space;

* Updated Eigen include paths for iOS examples (#2841)

* Updated Eigen hashes

* Updated Eigen paths to a permanent link

* Merged Eigen header changes

* Merged Eigen header changes

6 files changed, 83 insertions, 33 deletions

diff --git a/tensorflow/contrib/ios_examples/camera/camera_example.xcodeproj/project.pbxproj b/tensorflow/contrib/ios_examples/camera/camera_example.xcodeproj/project.pbxproj
index 0156188577..14785cc708 100644
--- a/tensorflow/contrib/ios_examples/camera/camera_example.xcodeproj/project.pbxproj
+++ b/tensorflow/contrib/ios_examples/camera/camera_example.xcodeproj/project.pbxproj
@@ -285,7 +285,7 @@
 				GCC_WARN_UNUSED_VARIABLE = YES;
 				HEADER_SEARCH_PATHS = (
 					"$(SRCROOT)/../../makefile/gen/proto",
-					"$(SRCROOT)/../../makefile/downloads/eigen-eigen-f3a13643ac1f",
+					"$(SRCROOT)/../../makefile/downloads/eigen-latest",
 					"$(SRCROOT)/../../makefile/downloads",
 					"$(SRCROOT)/../../makefile/downloads/protobuf/src/",
 					"$(SRCROOT)/../../../..",
@@ -300,6 +300,12 @@
 				OTHER_LDFLAGS = (
 					"-force_load",
 					"$(SRCROOT)/../../makefile/gen/lib/libtensorflow-core.a",
+					"-Xlinker",
+					"-S",
+					"-Xlinker",
+					"-x",
+					"-Xlinker",
+					"-dead_strip",
 				);
 				PRODUCT_BUNDLE_IDENTIFIER = com.google.CameraExample;
 				PRODUCT_NAME = "$(TARGET_NAME)";
@@ -344,7 +350,7 @@
 				GCC_WARN_UNUSED_VARIABLE = YES;
 				HEADER_SEARCH_PATHS = (
 					"$(SRCROOT)/../../makefile/gen/proto",
-					"$(SRCROOT)/../../makefile/downloads/eigen-eigen-f3a13643ac1f",
+					"$(SRCROOT)/../../makefile/downloads/eigen-latest",
 					"$(SRCROOT)/../../makefile/downloads",
 					"$(SRCROOT)/../../makefile/downloads/protobuf/src/",
 					"$(SRCROOT)/../../../..",
@@ -359,6 +365,12 @@
 				OTHER_LDFLAGS = (
 					"-force_load",
 					"$(SRCROOT)/../../makefile/gen/lib/libtensorflow-core.a",
+					"-Xlinker",
+					"-S",
+					"-Xlinker",
+					"-x",
+					"-Xlinker",
+					"-dead_strip",
 				);
 				PRODUCT_BUNDLE_IDENTIFIER = com.google.CameraExample;
 				PRODUCT_NAME = "$(TARGET_NAME)";
diff --git a/tensorflow/contrib/ios_examples/simple/tf_ios_makefile_example.xcodeproj/project.pbxproj b/tensorflow/contrib/ios_examples/simple/tf_ios_makefile_example.xcodeproj/project.pbxproj
index 91866cecac..a81286a5b1 100644
--- a/tensorflow/contrib/ios_examples/simple/tf_ios_makefile_example.xcodeproj/project.pbxproj
+++ b/tensorflow/contrib/ios_examples/simple/tf_ios_makefile_example.xcodeproj/project.pbxproj
@@ -276,8 +276,8 @@
 					"$(SRCROOT)/../../../..",
 					"$(SRCROOT)/../../makefile/downloads/protobuf/src/",
 					"$(SRCROOT)/../../makefile/downloads",
-					"$(SRCROOT)/../../makefile/downloads/eigen-eigen-f3a13643ac1f",
 					"$(SRCROOT)/../../makefile/gen/proto",
+					"$(SRCROOT)/../../makefile/downloads/eigen-latest",
 				);
 				INFOPLIST_FILE = "$(SRCROOT)/RunModel-Info.plist";
 				IPHONEOS_DEPLOYMENT_TARGET = 9.2;
@@ -289,6 +289,12 @@
 				OTHER_LDFLAGS = (
 					"-force_load",
 					"$(SRCROOT)/../../makefile/gen/lib/libtensorflow-core.a",
+					"-Xlinker",
+					"-S",
+					"-Xlinker",
+					"-x",
+					"-Xlinker",
+					"-dead_strip",
 				);
 				PRODUCT_BUNDLE_IDENTIFIER = "com.google.TF-Test";
 				PRODUCT_NAME = "$(TARGET_NAME)";
@@ -304,8 +310,8 @@
 					"$(SRCROOT)/../../../..",
 					"$(SRCROOT)/../../makefile/downloads/protobuf/src/",
 					"$(SRCROOT)/../../makefile/downloads",
-					"$(SRCROOT)/../../makefile/downloads/eigen-eigen-f3a13643ac1f",
 					"$(SRCROOT)/../../makefile/gen/proto",
+					"$(SRCROOT)/../../makefile/downloads/eigen-latest",
 				);
 				INFOPLIST_FILE = "$(SRCROOT)/RunModel-Info.plist";
 				IPHONEOS_DEPLOYMENT_TARGET = 9.2;
@@ -314,10 +320,16 @@
 					"$(SRCROOT)/../../makefile/gen/protobuf_ios/lib",
 					"$(SRCROOT)/../../makefile/gen/lib",
 				);
-				ONLY_ACTIVE_ARCH = NO;
+				ONLY_ACTIVE_ARCH = YES;
 				OTHER_LDFLAGS = (
 					"-force_load",
 					"$(SRCROOT)/../../makefile/gen/lib/libtensorflow-core.a",
+					"-Xlinker",
+					"-S",
+					"-Xlinker",
+					"-x",
+					"-Xlinker",
+					"-dead_strip",
 				);
 				PRODUCT_BUNDLE_IDENTIFIER = "com.google.TF-Test";
 				PRODUCT_NAME = "$(TARGET_NAME)";
diff --git a/tensorflow/contrib/makefile/Makefile b/tensorflow/contrib/makefile/Makefile
index 984250ce83..86ad8f41c1 100644
--- a/tensorflow/contrib/makefile/Makefile
+++ b/tensorflow/contrib/makefile/Makefile
@@ -35,8 +35,8 @@ HOST_OBJDIR := $(MAKEFILE_DIR)/gen/host_obj/
 HOST_BINDIR := $(MAKEFILE_DIR)/gen/host_bin/
 HOST_GENDIR := $(MAKEFILE_DIR)/gen/host_obj/
 
-# Which Eigen version we're using.
-EIGEN_HASH := d02e6a705c30
+# Find the current Eigen version name from the Bazel build file
+EIGEN_HASH := $(shell cat eigen.BUILD | grep archive_dir | head -1 | cut -f3 -d- | cut -f1 -d\")
 
 # Settings for the host compiler.
 HOST_CXX := gcc
@@ -56,9 +56,15 @@ HOST_LIBS := \
 
 # If we're on Linux, also link in the dl library.
 ifeq ($(HOST_OS),LINUX)
-	HOST_LIBS += -ldl
+	HOST_LIBS += -ldl -lpthread
 endif
 
+# If we're on a Pi, link in pthreads and dl
+ifeq ($(HOST_OS),PI)
+	HOST_LIBS += -ldl -lpthread
+endif
+
+
 # proto_text is a tool that converts protobufs into a form we can use more
 # compactly within TensorFlow. It's a bit like protoc, but is designed to
 # produce a much more minimal result so we can save binary space.
@@ -125,13 +131,13 @@ ifeq ($(TARGET),LINUX)
 endif
 # If we're on Linux, also link in the dl library.
 ifeq ($(TARGET),LINUX)
-	LIBS += -ldl
+	LIBS += -ldl -lpthread
 endif
 # If we're cross-compiling for the Raspberry Pi, use the right gcc.
 ifeq ($(TARGET),PI)
-	CXX := arm-linux-gnueabihf-g++
-	LDFLAGS := -L$(GENDIR)protobuf_pi/lib/ -Wl,--no-whole-archive
-	LIBS += -ldl
+	CXXFLAGS += -D__ANDROID_TYPES_SLIM__
+	LDFLAGS := -Wl,--no-whole-archive
+	LIBS += -ldl -lpthread
 	LIBFLAGS += -Wl,--allow-multiple-definition -Wl,--whole-archive
 endif
 
@@ -169,12 +175,16 @@ ifeq ($(TARGET),IOS)
 		-Wno-c++11-narrowing \
 		-mno-thumb \
 		-DTF_LEAN_BINARY \
+		-D__ANDROID_TYPES_SLIM__ \
 		-DMIN_LOG_LEVEL=0 \
 		-fno-exceptions \
 		-isysroot \
 		${IPHONEOS_SYSROOT}
 		LDFLAGS := -arch armv7 \
 		-miphoneos-version-min=${MIN_SDK_VERSION} \
+		-Xlinker -S \
+		-Xlinker -x \
+		-Xlinker -dead_strip \
 		-all_load \
 		-L$(GENDIR)protobuf_ios/lib \
 		-lz
@@ -186,6 +196,7 @@ ifeq ($(TARGET),IOS)
 		-Wno-c++11-narrowing \
 		-mno-thumb \
 		-DTF_LEAN_BINARY \
+		-D__ANDROID_TYPES_SLIM__ \
 		-DMIN_LOG_LEVEL=0 \
 		-fno-exceptions \
 		-isysroot \
@@ -205,6 +216,7 @@ ifeq ($(TARGET),IOS)
 		-D__thread= \
 		-Wno-c++11-narrowing \
 		-DTF_LEAN_BINARY \
+		-D__ANDROID_TYPES_SLIM__ \
 		-DMIN_LOG_LEVEL=0 \
 		-fno-exceptions \
 		-isysroot \
@@ -224,6 +236,7 @@ ifeq ($(TARGET),IOS)
 		-D__thread= \
 		-Wno-c++11-narrowing \
 		-DTF_LEAN_BINARY \
+		-D__ANDROID_TYPES_SLIM__ \
 		-DMIN_LOG_LEVEL=0 \
 		-fno-exceptions \
 		-isysroot \
@@ -243,6 +256,7 @@ ifeq ($(TARGET),IOS)
 		-D__thread= \
 		-Wno-c++11-narrowing \
 		-DTF_LEAN_BINARY \
+		-D__ANDROID_TYPES_SLIM__ \
 		-DMIN_LOG_LEVEL=0 \
 		-fno-exceptions \
 		-isysroot \
diff --git a/tensorflow/contrib/makefile/README.md b/tensorflow/contrib/makefile/README.md
index f82b70187c..f7f46fca5c 100644
--- a/tensorflow/contrib/makefile/README.md
+++ b/tensorflow/contrib/makefile/README.md
@@ -42,7 +42,7 @@ at `tensorflow/contrib/makefile/gen/bin/benchmark`. To run the executable, use:
 tensorflow/contrib/makefile/gen/bin/benchmark --graph=tensorflow_inception_graph.pb
 ```
 
-You should download the example graph from [http://download.tensorflow.org/models/image/imagenet/inception-2015-12-05.tgz](http://download.tensorflow.org/models/image/imagenet/inception-2015-12-05.tgz).
+You should download the example graph from [https://storage.googleapis.com/download.tensorflow.org/models/inception5h.zip](https://storage.googleapis.com/download.tensorflow.org/models/inception5h.zip).
 
 ## Supported Systems
 
@@ -132,24 +132,31 @@ static library in a simple app.
 
 ## Raspberry Pi
 
-The easiest way to build for the Raspberry Pi is to cross-compile from Linux.
-To use this makefile to do that, you first need to install the right version of
-the compiler to target the Pi, using a command like this on your Linux machine:
+Building on the Raspberry Pi is similar to a normal Linux system, though we
+recommend starting by compiling and installing protobuf:
 
 ```bash
-sudo apt-get install g++-arm-linux-gnueabihf
+cd tensorflow/contrib/makefile/downloads/protobuf/
+./autogen.sh 
+./configure
+make
+sudo make install
+cd ../../../../..
 ```
 
-After that, run `tensorflow/contrib/makefile/compile_pi_protobuf.sh` to build a
-version of the protobuf library aimed at the Pi. Then you should be able to run:
+Once that's done, you can use make to build the library and example:
 
 ```bash
-make -f tensorflow/contrib/makefile/Makefile TARGET=PI
+make -f tensorflow/contrib/makefile/Makefile HOST_OS=PI TARGET=PI OPTFLAGS="-Os"
 ```
 
-This will build the static library, and the example benchmark executable. You
-can then copy the `tensorflow/contrib/makefile/gen/bin/benchmark` program over
-to your Raspberry Pi, and run it there.
+If you're only interested in building for Raspberry Pi's 2 and 3, you can supply
+some extra optimization flags to give you code that will run faster:
+
+```bash
+make -f tensorflow/contrib/makefile/Makefile HOST_OS=PI TARGET=PI \
+OPTFLAGS="-Os -mfpu=neon-vfpv4 -funsafe-math-optimizations -ftree-vectorize"
+```
 
 ## Dependencies
 
diff --git a/tensorflow/contrib/makefile/download_dependencies.sh b/tensorflow/contrib/makefile/download_dependencies.sh
index 2ff9013804..0596b7ddf4 100755
--- a/tensorflow/contrib/makefile/download_dependencies.sh
+++ b/tensorflow/contrib/makefile/download_dependencies.sh
@@ -18,7 +18,9 @@ DOWNLOADS_DIR=tensorflow/contrib/makefile/downloads
 
 mkdir ${DOWNLOADS_DIR}
 
-EIGEN_HASH=d02e6a705c30
+# Grab the current Eigen version name from the Bazel build file
+EIGEN_HASH=$(cat eigen.BUILD | grep archive_dir | head -1 | cut -f3 -d- | cut -f1 -d\")
+
 curl "https://bitbucket.org/eigen/eigen/get/${EIGEN_HASH}.tar.gz" \
 -o /tmp/eigen-${EIGEN_HASH}.tar.gz
 tar xzf /tmp/eigen-${EIGEN_HASH}.tar.gz -C ${DOWNLOADS_DIR}
@@ -27,12 +29,8 @@ git clone https://github.com/google/re2.git ${DOWNLOADS_DIR}/re2
 git clone https://github.com/google/gemmlowp.git ${DOWNLOADS_DIR}/gemmlowp
 git clone https://github.com/google/protobuf.git ${DOWNLOADS_DIR}/protobuf
 
-# JPEG_VERSION=v9a
-# curl "http://www.ijg.org/files/jpegsrc.${JPEG_VERSION}.tar.gz" \
-# -o /tmp/jpegsrc.${JPEG_VERSION}.tar.gz
-# tar xzf /tmp/jpegsrc.${JPEG_VERSION}.tar.gz -C ${DOWNLOADS_DIR}
-
-# PNG_VERSION=v1.2.53
-# curl -L "https://github.com/glennrp/libpng/archive/${PNG_VERSION}.zip" \
-# -o /tmp/pngsrc.${PNG_VERSION}.zip
-# unzip /tmp/pngsrc.${PNG_VERSION}.zip -d ${DOWNLOADS_DIR}
+# Link to the downloaded Eigen library from a permanent directory name, since
+# the downloaded name changes with every version.
+cd ${DOWNLOADS_DIR}
+rm -rf eigen-latest
+ln -s eigen-eigen-${EIGEN_HASH} eigen-latest
diff --git a/tensorflow/core/platform/platform.h b/tensorflow/core/platform/platform.h
index 8f71a617b6..02731d9275 100644
--- a/tensorflow/core/platform/platform.h
+++ b/tensorflow/core/platform/platform.h
@@ -37,6 +37,13 @@ limitations under the License.
 #define IS_MOBILE_PLATFORM
 #endif
 
+#elif defined(__arm__)
+#define PLATFORM_POSIX
+
+// Since there's no macro for the Raspberry Pi, assume we're on a mobile
+// platform if we're compiling for the ARM CPU.
+#define IS_MOBILE_PLATFORM
+
 #else
 // If no platform specified, use:
 #define PLATFORM_POSIX