added perf test for dot product (8U, 32S, 32F)

modules/core/perf/perf_dot.cpp

+#include "perf_precomp.hpp"
+
+using namespace std;
+using namespace cv;
+using namespace perf;
+
+typedef tr1::tuple<int, int> MatType_Length_t;
+typedef TestBaseWithParam<MatType_Length_t> MatType_Length;
+
+PERF_TEST_P( MatType_Length, dot,
+             testing::Combine(
+                testing::Values( CV_8UC1, CV_32SC1, CV_32FC1 ),
+                testing::Values( 32, 64, 128, 256, 512, 1024 )
+            ))
+{
+    unsigned int type = std::tr1::get<0>(GetParam());
+    unsigned int size = std::tr1::get<1>(GetParam());
+    Mat a(size, size, type);
+    Mat b(size, size, type);
+
+    declare.in(a, WARMUP_RNG);
+    declare.in(b, WARMUP_RNG);
+
+    double product;
+
+	TEST_CYCLE(100)
+	{
+        product = a.dot(b);
+	}
+
+    SANITY_CHECK(product, 1e-5);
+}