From d35e2f533905a65cf1b5c3ff7b5cfc11b210aaf9 Mon Sep 17 00:00:00 2001
From: Alexander Alekhin <alexander.a.alekhin@gmail.com>
Date: Wed, 2 Dec 2020 00:21:19 +0000
Subject: [PATCH] core(ipp): workaround getIppTopFeatures() value mismatch

---
 modules/core/src/system.cpp | 15 +++++++++------
 modules/ts/src/ts.cpp       |  4 +++-
 2 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/modules/core/src/system.cpp b/modules/core/src/system.cpp
index fcb9ea45ef..ad688a6c68 100644
--- a/modules/core/src/system.cpp
+++ b/modules/core/src/system.cpp
@@ -2429,6 +2429,13 @@ public:
             ippTopFeatures = ippCPUID_SSE42;
 
         pIppLibInfo = ippiGetLibVersion();
+
+        // workaround: https://github.com/opencv/opencv/issues/12959
+        std::string ippName(pIppLibInfo->Name ? pIppLibInfo->Name : "");
+        if (ippName.find("SSE4.2") != std::string::npos)
+        {
+            ippTopFeatures = ippCPUID_SSE42;
+        }
     }
 
 public:
@@ -2468,16 +2475,12 @@ int getIppFeatures()
 #endif
 }
 
-unsigned long long getIppTopFeatures();
-
+#ifdef HAVE_IPP
 unsigned long long getIppTopFeatures()
 {
-#ifdef HAVE_IPP
     return getIPPSingleton().ippTopFeatures;
-#else
-    return 0;
-#endif
 }
+#endif
 
 void setIppStatus(int status, const char * const _funcname, const char * const _filename, int _line)
 {
diff --git a/modules/ts/src/ts.cpp b/modules/ts/src/ts.cpp
index bad799dc4d..13f5eff251 100644
--- a/modules/ts/src/ts.cpp
+++ b/modules/ts/src/ts.cpp
@@ -1122,7 +1122,9 @@ void SystemInfoCollector::OnTestProgramStart(const testing::UnitTest&)
     }
     recordPropertyVerbose("cv_cpu_features", "CPU features", cv::getCPUFeaturesLine());
 #ifdef HAVE_IPP
-    recordPropertyVerbose("cv_ipp_version", "Intel(R) IPP version", cv::ipp::useIPP() ? cv::ipp::getIppVersion() :  "disabled");
+    recordPropertyVerbose("cv_ipp_version", "Intel(R) IPP version", cv::ipp::useIPP() ? cv::ipp::getIppVersion() : "disabled");
+    if (cv::ipp::useIPP())
+        recordPropertyVerbose("cv_ipp_features", "Intel(R) IPP features code", cv::format("0x%llx", cv::ipp::getIppTopFeatures()));
 #endif
 #ifdef HAVE_OPENCL
     cv::dumpOpenCLInformation();