GPU Calc: optimize KURT

Change-Id: Iab842ff0417a8e7da8c4b44ca525de8f1c2c8738
Signed-off-by: I-Jui (Ray) Sung <ray@multicorewareinc.com>

sc/source/core/opencl/op_statistical.cxx

@@ -5159,68 +5159,95 @@ void OpKurt:: GenSlidingWindowFunction(std::stringstream &ss,
         ss << ") {\n";
         ss << "    int gid0 = get_global_id(0);\n";
         ss << "    double fSum = 0.0;\n";
-        ss << "    double vSum = 0.0;\n";
+        ss<<  "    double xpower4 = 0.0;\n";
+        ss<<  "    double fMean =0.0;\n";
+        ss<<  "    double fStdDev = 0.0;\n";
         ss << "    int length="<<nCurWindowSize<<";\n";
         ss << "    double tmp = 0;\n";
-        ss << "    for (int i = 0; i <" << nCurWindowSize << "; i++)\n";
-        ss << "    {\n";
-        ss << "        double arg0 = ";
-        ss<< vSubArguments[0]->GenSlidingWindowDeclRef();
-        ss << ";\n";
+        for (unsigned i = 0; i < vSubArguments.size(); i++)
+        {
+            FormulaToken *pCur = vSubArguments[i]->GetFormulaToken();
+            assert(pCur);
+            if (pCur->GetType() == formula::svDoubleVectorRef)
+            {
+                const formula::DoubleVectorRefToken* pDVR =
+                dynamic_cast<const formula::DoubleVectorRefToken *>(pCur);
+                size_t nCurWindowSize = pDVR->GetRefRowSize();
+                ss << "    for (int i = 0; i <" << nCurWindowSize;
+                ss << "; i++)\n";
+                ss << "    {\n";
+                ss << "        double arg0 = ";
+                ss<< vSubArguments[i]->GenSlidingWindowDeclRef();
+                ss << ";\n";
 #ifdef ISNAN
-        ss<< "        if(isNan(arg0)||((gid0+i)>=";
-        ss<<pCurDVR->GetArrayLength();
-        ss<< "))\n";
-        ss<< "        {\n";
-        ss<< "            length--;\n";
-        ss<< "            continue;\n";
-        ss<< "        }\n";
-#endif
-        ss<< "        fSum += arg0;\n";
-        ss<< "    }\n";
-        ss<< "    double fMean = fSum / length;\n";
-        ss<< "    for (int i = 0; i <" << nCurWindowSize << "; i++)\n";
-        ss<< "    {\n";
-        ss<< "        double arg0 = ";
-        ss<< vSubArguments[0]->GenSlidingWindowDeclRef();
-        ss<< ";\n";
+                ss<< "        if(isNan(arg0)||((gid0+i)>=";
+                ss<<pCurDVR->GetArrayLength();
+                ss<< "))\n";
+                ss<< "        {\n";
+                ss<< "            length--;\n";
+                ss<< "            continue;\n";
+                ss<< "        }\n";
+#endif
+                ss<< "        fSum += arg0;\n";
+                ss<< "    }\n";
+                ss<< "    fMean = fSum / length;\n";
+                ss<< "    fSum=0.0;\n";
+                ss<< "    for (int i = 0; i <" << nCurWindowSize << "; i++)\n";
+                ss<< "    {\n";
+                ss<< "        double arg0 = ";
+                ss<< vSubArguments[i]->GenSlidingWindowDeclRef();
+                ss<< ";\n";
 #ifdef ISNAN
-        ss<< "        if(isNan(arg0)||((gid0+i)>=";
-        ss<< pCurDVR->GetArrayLength();
-        ss<< "))\n";
-        ss<< "        {\n";
-        ss<< "            continue;\n";
-        ss<< "        }\n";
-#endif
-        ss<< "        vSum += (arg0 - fMean) * (arg0 - fMean);\n";
-        ss<< "    }\n";
-        ss<< "    double fStdDev = sqrt(vSum / (length - 1.0));\n";
-        ss<< "    double dx = 0.0;\n";
-        ss<< "    double xpower4 = 0.0;\n";
-        ss<< "    for (int i = 0; i <" << nCurWindowSize << "; i++)\n";
-        ss<< "    {\n";
-        ss<< "        double arg0 = ";
-        ss<< vSubArguments[0]->GenSlidingWindowDeclRef();
-        ss<< ";\n";
+                ss<< "        if(isNan(arg0)||((gid0+i)>=";
+                ss<< pCurDVR->GetArrayLength();
+                ss<< "))\n";
+                ss<< "        {\n";
+                ss<< "            continue;\n";
+                ss<< "        }\n";
+#endif
+                ss<< "        fSum += pow(arg0 - fMean, 2);\n";
+                ss<< "    }\n";
+                ss<< "    fStdDev = sqrt(fSum / (length - 1.0));\n";
+                ss<< "    fSum = 0.0;\n";
+                ss<< "    for (int i = 0; i <" << nCurWindowSize << "; i++)\n";
+                ss<< "    {\n";
+                ss<< "        double arg0 = ";
+                ss<< vSubArguments[i]->GenSlidingWindowDeclRef();
+                ss<< ";\n";
 #ifdef ISNAN
-        ss<< "        if(isNan(arg0)||((gid0+i)>=";
-        ss<< pCurDVR->GetArrayLength();
-        ss<< "))\n";
-        ss<< "        {\n";
-        ss<< "            continue;\n";
-        ss<< "        }\n";
-#endif
-        ss<< "        dx = (arg0 -fMean) / fStdDev;\n";
-        ss<< "        xpower4 = xpower4 + (dx * dx * dx * dx);\n";
-        ss<< "    }\n";
-        ss<< "    double k_d = (length - 2.0) * (length - 3.0);\n";
-        ss<< "    double k_l = length * (length + 1.0) /";
-        ss<< "((length - 1.0) * k_d);\n";
-        ss<< "    double k_t = 3.0 * (length - 1.0) * (length - 1.0) / k_d;\n";
-        ss<< "    tmp = xpower4 * k_l - k_t;\n";
+                ss<< "        if(isNan(arg0)||((gid0+i)>=";
+                ss<< pCurDVR->GetArrayLength();
+                ss<< "))\n";
+                ss<< "        {\n";
+                ss<< "            continue;\n";
+                ss<< "        }\n";
+#endif
+                ss<< "        fSum = (arg0 -fMean) / fStdDev;\n";
+                ss<< "        xpower4 += pow(fSum, 4);\n";
+                ss<< "    }\n";
+            }
+            else if (pCur->GetType() == formula::svSingleVectorRef)
+            {
+#ifdef  ISNAN
+                ss << "return HUGE_VAL";
+#endif
+            }
+            else if (pCur->GetType() == formula::svDouble)
+            {
+#ifdef  ISNAN
+                ss << "return HUGE_VAL";
+#endif
+            }
+        }
+        ss<< "    fSum = (length - 2.0) * (length - 3.0);\n";
+        ss<< "    fMean = length * (length + 1.0) /";
+        ss<< "((length - 1.0) * fSum);\n";
+        ss<< "    fStdDev = 3.0 * (length - 1.0) * (length - 1.0) / fSum;\n";
+        ss<< "    tmp = xpower4 * fMean - fStdDev;\n";
         ss<< "    return tmp;\n";
         ss<< "}";
 }
+
 void OpIntercept::GenSlidingWindowFunction(std::stringstream &ss,
             const std::string sSymName, SubArguments &vSubArguments)
 {