Set MKLROOT when building MKLDNN (#1093)

* finally have something almost acceptable

cmake/external_mkldnn.cmake

@@ -41,6 +41,38 @@ if(MKLDNN_INCLUDE_DIR AND MKLDNN_LIB_DIR)
     return()
 endif()
 
+# This section sets up MKL as an external project to be used later by MKLDNN
+
+set(MKLURLROOT "https://github.com/intel/mkl-dnn/releases/download/v0.14/")
+set(MKLVERSION "2018.0.3.20180406")
+if (${CMAKE_SYSTEM_NAME} STREQUAL "Linux")
+    set(MKLPACKAGE "mklml_lnx_${MKLVERSION}.tgz")
+    set(MKL_SHA1_HASH aea0d9ce65773cfcf5d8292b8db553bde965fc8f)
+elseif (${CMAKE_SYSTEM_NAME} STREQUAL "Darwin")
+    set(MKLPACKAGE "mklml_mac_${MKLVERSION}.tgz")
+    set(MKL_SHA1_HASH d76083fd5a79767a96572ad0e23e7f4c892818f2)
+elseif (${CMAKE_SYSTEM_NAME} STREQUAL "Windows")
+    set(MKLPACKAGE "mklml_win_${MKLVERSION}.tgz")
+    set(MKL_SHA1_HASH d607ca92d7bfc101f0828c0b005098b75531669b)
+endif()
+set(MKLURL ${MKLURLROOT}${MKLPACKAGE})
+
+ExternalProject_Add(
+    ext_mkl
+    PREFIX mkl
+    URL ${MKLURL}
+    URL_HASH SHA1=${MKL_SHA1_HASH}
+    CONFIGURE_COMMAND ""
+    BUILD_COMMAND ""
+    INSTALL_COMMAND ""
+    UPDATE_COMMAND ""
+    DOWNLOAD_NO_PROGRESS TRUE
+    EXCLUDE_FROM_ALL TRUE
+)
+ExternalProject_Get_Property(ext_mkl source_dir)
+set(MKL_ROOT ${EXTERNAL_PROJECTS_ROOT}/mkldnn/src/external/mkl)
+set(MKL_SOURCE_DIR ${source_dir})
+
 set(MKLDNN_GIT_REPO_URL https://github.com/intel/mkl-dnn)
 set(MKLDNN_GIT_TAG "0e7ca73")
 
@@ -48,9 +80,11 @@ set(MKLDNN_GIT_TAG "0e7ca73")
 if(${CMAKE_VERSION} VERSION_LESS 3.2)
     ExternalProject_Add(
         ext_mkldnn
+        DEPENDS ext_mkl
         GIT_REPOSITORY ${MKLDNN_GIT_REPO_URL}
         GIT_TAG ${MKLDNN_GIT_TAG}
         UPDATE_COMMAND ""
+        CONFIGURE_COMMAND
         # Uncomment below with any in-flight MKL-DNN patches
         # PATCH_COMMAND patch -p1 < ${CMAKE_SOURCE_DIR}/third-party/patches/mkldnn-cmake-openmp.patch
         CMAKE_ARGS
@@ -60,6 +94,7 @@ if(${CMAKE_VERSION} VERSION_LESS 3.2)
             -DCMAKE_C_COMPILER=${CMAKE_C_COMPILER}
             -DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}
             -DCMAKE_INSTALL_PREFIX=${EXTERNAL_PROJECTS_ROOT}/mkldnn
+            -DMKLROOT=${MKL_ROOT}
         TMP_DIR "${EXTERNAL_PROJECTS_ROOT}/mkldnn/tmp"
         STAMP_DIR "${EXTERNAL_PROJECTS_ROOT}/mkldnn/stamp"
         DOWNLOAD_DIR "${EXTERNAL_PROJECTS_ROOT}/mkldnn/download"
@@ -71,6 +106,7 @@ if(${CMAKE_VERSION} VERSION_LESS 3.2)
 else()
     ExternalProject_Add(
         ext_mkldnn
+        DEPENDS ext_mkl
         GIT_REPOSITORY ${MKLDNN_GIT_REPO_URL}
         GIT_TAG ${MKLDNN_GIT_TAG}
         UPDATE_COMMAND ""
@@ -83,6 +119,7 @@ else()
             -DCMAKE_C_COMPILER=${CMAKE_C_COMPILER}
             -DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}
             -DCMAKE_INSTALL_PREFIX=${EXTERNAL_PROJECTS_ROOT}/mkldnn
+            -DMKLROOT=${MKL_ROOT}
         TMP_DIR "${EXTERNAL_PROJECTS_ROOT}/mkldnn/tmp"
         STAMP_DIR "${EXTERNAL_PROJECTS_ROOT}/mkldnn/stamp"
         DOWNLOAD_DIR "${EXTERNAL_PROJECTS_ROOT}/mkldnn/download"
@@ -94,12 +131,10 @@ else()
         )
 endif()
 
-ExternalProject_Get_Property(ext_mkldnn source_dir binary_dir)
-
 ExternalProject_Add_Step(
     ext_mkldnn
     PrepareMKL
-    COMMAND ${source_dir}/scripts/prepare_mkl.sh
+    COMMAND ${CMAKE_COMMAND} -E copy_directory ${MKL_SOURCE_DIR} ${MKL_ROOT}
     DEPENDEES download
     DEPENDERS configure
     )