dnn: add OPENCV_DNN_DISABLE_MEMORY_OPTIMIZATIONS runtime option

replaces REUSE_DNN_MEMORY compile-time option

modules/dnn/CMakeLists.txt

@@ -97,8 +97,3 @@ if(BUILD_PERF_TESTS)
     endif()
   endif()
 endif()
-
-ocv_option(${the_module}_REUSE_MEMORY "Enable reusing strategy of memory management" ON)
-if (${the_module}_REUSE_MEMORY)
-  add_definitions(-DREUSE_DNN_MEMORY=1)
-endif()

modules/dnn/src/dnn.cpp

@@ -51,10 +51,15 @@
 #include <opencv2/dnn/shape_utils.hpp>
 #include <opencv2/imgproc.hpp>
 
+#include <opencv2/core/utils/configuration.private.hpp>
+
 namespace cv {
 namespace dnn {
 CV__DNN_EXPERIMENTAL_NS_BEGIN
 
+// this option is usefull to run valgrind memory errors detection
+static bool DNN_DISABLE_MEMORY_OPTIMIZATIONS = utils::getConfigurationParameterBool("OPENCV_DNN_DISABLE_MEMORY_OPTIMIZATIONS", false);
+
 using std::vector;
 using std::map;
 using std::make_pair;
@@ -369,7 +374,8 @@ public:
 
     void reuseOrCreate(const MatShape& shape, const LayerPin& lp, Mat& dst)
     {
-#ifdef REUSE_DNN_MEMORY
+        if (!DNN_DISABLE_MEMORY_OPTIMIZATIONS)
+        {
             Mat bestBlob;
             LayerPin bestBlobPin;
 
@@ -400,9 +406,10 @@ public:
             {
                 reuse(bestBlobPin, lp);
                 dst = bestBlob.reshape(1, 1).colRange(0, targetTotal).reshape(1, shape);
+                return;
             }
-        else
-#endif  // REUSE_DNN_MEMORY
+        }
+
         {
             // if dst already has been allocated with total(shape) elements,
             // it won't be recrreated and pointer of dst.data remains the same.
@@ -413,7 +420,8 @@ public:
 
     void reuseOrCreate(const MatShape& shape, const LayerPin& lp, UMat &umat_dst)
     {
-#ifdef REUSE_DNN_MEMORY
+        if (!DNN_DISABLE_MEMORY_OPTIMIZATIONS)
+        {
             UMat bestBlob;
             LayerPin bestBlobPin;
 
@@ -444,9 +452,10 @@ public:
             {
                 reuse(bestBlobPin, lp);
                 umat_dst.create(shape, CV_32F);
+                return;
             }
-        else
-#endif  // REUSE_DNN_MEMORY
+        }
+
         {
             // if dst already has been allocated with total(shape) elements,
             // it won't be recrreated and pointer of dst.data remains the same.