Merge pull request #11897 from Jakub-Golinowski:hpx_backend

* Add HPX backend for OpenCV implementation
Adds hpx backend for cv::parallel_for_() calls respecting the nstripes chunking parameter. C++ code for the backend is added to modules/core/parallel.cpp. Also, the necessary changes to cmake files are introduced.
Backend can operate in 2 versions (selectable by cmake build option WITH_HPX_STARTSTOP): hpx (runtime always on) and hpx_startstop (start and stop the backend for each cv::parallel_for_() call)

* WIP: Conditionally include hpx_main.hpp to tests in core module
Header hpx_main.hpp is included to both core/perf/perf_main.cpp and core/test/test_main.cpp.
The changes to cmake files for linking hpx library to above mentioned test executalbles are proposed but have issues.

* Add coditional iclusion of hpx_main.hpp to cpp cpu modules

* Remove start/stop version of hpx backend

CMakeLists.txt

@@ -252,6 +252,7 @@ OCV_OPTION(WITH_WIN32UI        "Build with Win32 UI Backend support"         ON
 OCV_OPTION(WITH_QUICKTIME      "Use QuickTime for Video I/O"                 OFF  IF APPLE )
 OCV_OPTION(WITH_QTKIT          "Use QTKit Video I/O backend"                 OFF  IF APPLE )
 OCV_OPTION(WITH_TBB            "Include Intel TBB support"                   OFF  IF (NOT IOS AND NOT WINRT) )
+OCV_OPTION(WITH_HPX            "Include Ste||ar Group HPX support"           OFF)
 OCV_OPTION(WITH_OPENMP         "Include OpenMP support"                      OFF)
 OCV_OPTION(WITH_PTHREADS_PF    "Use pthreads-based parallel_for"             ON   IF (NOT WIN32 OR MINGW) )
 OCV_OPTION(WITH_TIFF           "Include TIFF support"                        ON   IF (NOT IOS) )
@@ -1353,6 +1354,7 @@ endif()
 # Order is similar to CV_PARALLEL_FRAMEWORK in core/src/parallel.cpp
 ocv_build_features_string(parallel_status EXCLUSIVE
   IF HAVE_TBB THEN "TBB (ver ${TBB_VERSION_MAJOR}.${TBB_VERSION_MINOR} interface ${TBB_INTERFACE_VERSION})"
+  IF HAVE_HPX THEN "HPX"
   IF HAVE_OPENMP THEN "OpenMP"
   IF HAVE_GCD THEN "GCD"
   IF WINRT OR HAVE_CONCURRENCY THEN "Concurrency"

cmake/OpenCVFindLibsPerf.cmake

@@ -7,6 +7,13 @@ if(WITH_TBB)
   include("${OpenCV_SOURCE_DIR}/cmake/OpenCVDetectTBB.cmake")
 endif(WITH_TBB)
 
+# --- HPX ---
+if(WITH_HPX)
+  find_package(HPX REQUIRED)
+  ocv_include_directories(${HPX_INCLUDE_DIRS})
+  set(HAVE_HPX TRUE)
+endif(WITH_HPX)
+
 # --- IPP ---
 if(WITH_IPP)
   include("${OpenCV_SOURCE_DIR}/cmake/OpenCVFindIPP.cmake")

cmake/OpenCVModule.cmake

@@ -1135,6 +1135,11 @@ function(ocv_add_perf_tests)
       ocv_target_link_libraries(${the_target} LINK_PRIVATE ${perf_deps} ${OPENCV_MODULE_${the_module}_DEPS} ${OPENCV_LINKER_LIBS} ${OPENCV_PERF_${the_module}_DEPS})
       add_dependencies(opencv_perf_tests ${the_target})
 
+      if(HAVE_HPX)
+        message("Linking HPX to Perf test of module ${name}")
+        ocv_target_link_libraries(${the_target} LINK_PRIVATE "${HPX_LIBRARIES}")
+      endif()
+
       set_target_properties(${the_target} PROPERTIES LABELS "${OPENCV_MODULE_${the_module}_LABEL};PerfTest")
       set_source_files_properties(${OPENCV_PERF_${the_module}_SOURCES} ${${the_target}_pch}
         PROPERTIES LABELS "${OPENCV_MODULE_${the_module}_LABEL};PerfTest")
@@ -1220,6 +1225,11 @@ function(ocv_add_accuracy_tests)
       ocv_target_link_libraries(${the_target} LINK_PRIVATE ${test_deps} ${OPENCV_MODULE_${the_module}_DEPS} ${OPENCV_LINKER_LIBS} ${OPENCV_TEST_${the_module}_DEPS})
       add_dependencies(opencv_tests ${the_target})
 
+      if(HAVE_HPX)
+        message("Linking HPX to Perf test of module ${name}")
+        ocv_target_link_libraries(${the_target} LINK_PRIVATE "${HPX_LIBRARIES}")
+      endif()
+
       set_target_properties(${the_target} PROPERTIES LABELS "${OPENCV_MODULE_${the_module}_LABEL};AccuracyTest")
       set_source_files_properties(${OPENCV_TEST_${the_module}_SOURCES} ${${the_target}_pch}
         PROPERTIES LABELS "${OPENCV_MODULE_${the_module}_LABEL};AccuracyTest")

cmake/templates/cvconfig.h.in

@@ -174,6 +174,9 @@
 /* Intel Threading Building Blocks */
 #cmakedefine HAVE_TBB
 
+/* Ste||ar Group High Performance ParallelX */
+#cmakedefine HAVE_HPX
+
 /* TIFF codec */
 #cmakedefine HAVE_TIFF
 

modules/calib3d/perf/perf_main.cpp

 #include "perf_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_PERF_TEST_MAIN(calib3d)

modules/calib3d/test/test_main.cpp

@@ -3,4 +3,8 @@
 // of this distribution and at http://opencv.org/license.html.
 #include "test_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_TEST_MAIN("")

modules/core/CMakeLists.txt

@@ -77,6 +77,10 @@ ocv_target_link_libraries(${the_module} LINK_PRIVATE
     "${OPENCV_HAL_LINKER_LIBS}"
 )
 
+if(HAVE_HPX)
+  ocv_target_link_libraries(${the_module} LINK_PRIVATE "${HPX_LIBRARIES}")
+endif()
+
 if(HAVE_CUDA)
   ocv_target_compile_definitions(${the_module} PUBLIC OPENCV_TRAITS_ENABLE_DEPRECATED)
 endif()

modules/core/perf/perf_main.cpp

@@ -5,4 +5,8 @@
 # endif
 #endif
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_PERF_TEST_MAIN(core)

modules/core/src/parallel.cpp

@@ -79,6 +79,7 @@
 
 /* IMPORTANT: always use the same order of defines
    - HAVE_TBB         - 3rdparty library, should be explicitly enabled
+   - HAVE_HPX         - 3rdparty library, should be explicitly enabled
    - HAVE_OPENMP      - integrated to compiler, should be explicitly enabled
    - HAVE_GCD         - system wide, used automatically        (APPLE only)
    - WINRT            - system wide, used automatically        (Windows RT only)
@@ -95,6 +96,16 @@
     #endif
     #undef min
     #undef max
+#elif defined HAVE_HPX
+    #include <hpx/parallel/algorithms/for_loop.hpp>
+    #include <hpx/parallel/execution.hpp>
+    //
+    #include <hpx/hpx_start.hpp>
+    #include <hpx/hpx_suspend.hpp>
+    #include <hpx/include/apply.hpp>
+    #include <hpx/util/yield_while.hpp>
+    #include <hpx/include/threadmanager.hpp>
+
 #elif defined HAVE_OPENMP
     #include <omp.h>
 #elif defined HAVE_GCD
@@ -109,6 +120,8 @@
 
 #if defined HAVE_TBB
 #  define CV_PARALLEL_FRAMEWORK "tbb"
+#elif defined HAVE_HPX
+#  define CV_PARALLEL_FRAMEWORK "hpx"
 #elif defined HAVE_OPENMP
 #  define CV_PARALLEL_FRAMEWORK "openmp"
 #elif defined HAVE_GCD
@@ -377,6 +390,26 @@ namespace
             tbb::parallel_for(tbb::blocked_range<int>(range.start, range.end), *this);
         }
     };
+#elif defined HAVE_HPX
+    class ProxyLoopBody : public ParallelLoopBodyWrapper
+    {
+    public:
+        ProxyLoopBody(ParallelLoopBodyWrapperContext& ctx_)
+                : ParallelLoopBodyWrapper(ctx_)
+        {}
+
+        void operator ()() const  // run parallel job
+        {
+            cv::Range stripeRange = this->stripeRange();
+            hpx::parallel::for_loop(
+                    hpx::parallel::execution::par,
+                    stripeRange.start, stripeRange.end,
+                    [&](const int &i) { ;
+                        this->ParallelLoopBodyWrapper::operator()(
+                                cv::Range(i, i + 1));
+                    });
+        }
+    };
 #elif defined HAVE_GCD
     typedef ParallelLoopBodyWrapper ProxyLoopBody;
     static void block_function(void* context, size_t index)
@@ -409,6 +442,8 @@ static int numThreads = -1;
     #else
         static tbb::task_scheduler_init tbbScheduler(tbb::task_scheduler_init::deferred);
     #endif
+#elif defined HAVE_HPX
+// nothing for HPX
 #elif defined HAVE_OPENMP
 static int numThreadsMax = omp_get_max_threads();
 #elif defined HAVE_GCD
@@ -508,6 +543,9 @@ static void parallel_for_impl(const cv::Range& range, const cv::ParallelLoopBody
         pbody();
 #endif
 
+#elif defined HAVE_HPX
+        pbody();
+
 #elif defined HAVE_OPENMP
 
         #pragma omp parallel for schedule(dynamic) num_threads(numThreads > 0 ? numThreads : numThreadsMax)
@@ -579,6 +617,9 @@ int cv::getNumThreads(void)
            : tbb::task_scheduler_init::default_num_threads();
 #endif
 
+#elif defined HAVE_HPX
+    return numThreads;
+
 #elif defined HAVE_OPENMP
 
     return numThreads > 0
@@ -653,6 +694,9 @@ void cv::setNumThreads( int threads_ )
     if(threads > 0) tbbScheduler.initialize(threads);
 #endif
 
+#elif defined HAVE_HPX
+    return; // nothing needed as numThreads is used
+
 #elif defined HAVE_OPENMP
 
     return; // nothing needed as num_threads clause is used in #pragma omp parallel for
@@ -702,6 +746,8 @@ int cv::getThreadNum(void)
     #else
         return 0;
     #endif
+#elif defined HAVE_HPX
+        return (int)(hpx::get_num_worker_threads());
 #elif defined HAVE_OPENMP
     return omp_get_thread_num();
 #elif defined HAVE_GCD

modules/core/test/test_main.cpp

@@ -3,4 +3,8 @@
 // of this distribution and at http://opencv.org/license.html.
 #include "test_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_TEST_MAIN("cv")

modules/dnn/perf/perf_main.cpp

@@ -7,6 +7,10 @@ static const char* extraTestDataPath =
         getenv("OPENCV_DNN_TEST_DATA_PATH");
 #endif
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_PERF_TEST_MAIN(dnn,
     extraTestDataPath ? (void)cvtest::addDataSearchPath(extraTestDataPath) : (void)0
 )

modules/dnn/test/test_main.cpp

@@ -7,6 +7,10 @@ static const char* extraTestDataPath =
         getenv("OPENCV_DNN_TEST_DATA_PATH");
 #endif
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_TEST_MAIN("",
     extraTestDataPath ? (void)cvtest::addDataSearchPath(extraTestDataPath) : (void)0
 )

modules/features2d/perf/perf_main.cpp

 #include "perf_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_PERF_TEST_MAIN(features2d)

modules/features2d/test/test_main.cpp

@@ -3,4 +3,8 @@
 // of this distribution and at http://opencv.org/license.html.
 #include "test_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_TEST_MAIN("cv")

modules/flann/test/test_main.cpp

 #include "test_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_TEST_MAIN("cv")

modules/highgui/test/test_main.cpp

@@ -3,4 +3,8 @@
 // of this distribution and at http://opencv.org/license.html.
 #include "test_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_TEST_MAIN("highgui")

modules/imgcodecs/perf/perf_main.cpp

@@ -3,4 +3,8 @@
 // of this distribution and at http://opencv.org/license.html
 #include "perf_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_PERF_TEST_MAIN(imgcodecs)

modules/imgcodecs/test/test_main.cpp

@@ -3,4 +3,8 @@
 // of this distribution and at http://opencv.org/license.html
 #include "test_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_TEST_MAIN("highgui")

modules/imgproc/perf/perf_main.cpp

@@ -3,4 +3,8 @@
 // of this distribution and at http://opencv.org/license.html.
 #include "perf_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_PERF_TEST_MAIN(imgproc)

modules/imgproc/test/test_main.cpp

@@ -3,4 +3,8 @@
 // of this distribution and at http://opencv.org/license.html.
 #include "test_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_TEST_MAIN("cv")

modules/ml/test/test_main.cpp

@@ -3,4 +3,8 @@
 // of this distribution and at http://opencv.org/license.html.
 #include "test_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_TEST_MAIN("ml")

modules/objdetect/perf/perf_main.cpp

 #include "perf_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_PERF_TEST_MAIN(objdetect)

modules/objdetect/test/test_main.cpp

@@ -3,4 +3,8 @@
 // of this distribution and at http://opencv.org/license.html.
 #include "test_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_TEST_MAIN("cv")

modules/photo/perf/perf_main.cpp

@@ -8,4 +8,8 @@ static const char * impls[] = {
     "plain"
 };
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_PERF_TEST_MAIN_WITH_IMPLS(photo, impls, perf::printCudaInfo())

modules/photo/test/test_main.cpp

@@ -3,4 +3,8 @@
 // of this distribution and at http://opencv.org/license.html.
 #include "test_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_TEST_MAIN("cv")

modules/shape/test/test_main.cpp

@@ -3,4 +3,8 @@
 // of this distribution and at http://opencv.org/license.html.
 #include "test_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_TEST_MAIN("cv")

modules/stitching/perf/perf_main.cpp

 #include "perf_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_PERF_TEST_MAIN(stitching)

modules/stitching/test/test_main.cpp

@@ -3,4 +3,8 @@
 // of this distribution and at http://opencv.org/license.html.
 #include "test_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_TEST_MAIN(".")

modules/superres/perf/perf_main.cpp

@@ -51,4 +51,8 @@ static const char * impls[] = {
     "plain"
 };
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_PERF_TEST_MAIN_WITH_IMPLS(superres, impls, printCudaInfo())

modules/superres/test/test_main.cpp

@@ -42,4 +42,8 @@
 
 #include "test_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_TEST_MAIN("superres")

modules/video/perf/perf_main.cpp

 #include "perf_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_PERF_TEST_MAIN(video)

modules/video/test/test_main.cpp

@@ -3,4 +3,8 @@
 // of this distribution and at http://opencv.org/license.html.
 #include "test_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_TEST_MAIN("cv")

modules/videoio/perf/perf_main.cpp

@@ -3,4 +3,8 @@
 // of this distribution and at http://opencv.org/license.html
 #include "perf_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_PERF_TEST_MAIN(videoio)

modules/videoio/test/test_main.cpp

@@ -3,4 +3,8 @@
 // of this distribution and at http://opencv.org/license.html.
 #include "test_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_TEST_MAIN("highgui")

modules/videostab/test/test_main.cpp

@@ -4,4 +4,8 @@
 
 #include "test_precomp.hpp"
 
+#if defined(HAVE_HPX)
+    #include <hpx/hpx_main.hpp>
+#endif
+
 CV_TEST_MAIN("cv")