Fixed a performance overhead in database creation: it is again a static variable now as it was before

2 files changed, 22 insertions, 18 deletions

diff --git a/src/database/database.cpp b/src/database/database.cpp
index ed56c65d..b2f70e49 100644
--- a/src/database/database.cpp
+++ b/src/database/database.cpp
@@ -39,6 +39,7 @@
 namespace clblast {
 // =================================================================================================
 
+std::vector<database::DatabaseEntry> Database::database = std::vector<database::DatabaseEntry>{};
 const std::vector<database::DatabaseEntry> Database::apple_cpu_fallback = std::vector<database::DatabaseEntry>{
   database::XaxpyApple, database::XdotApple,
   database::XgemvApple, database::XgemvFastApple, database::XgemvFastRotApple, database::XgerApple, database::XtrsvApple,
@@ -58,23 +59,26 @@ Database::Database(const Device &device, const std::string &kernel_name,
                    const Precision precision, const std::vector<database::DatabaseEntry> &overlay):
   parameters_(std::make_shared<database::Parameters>()) {
 
-  database = std::vector<database::DatabaseEntry>{
-      database::XaxpyHalf, database::XaxpySingle, database::XaxpyDouble, database::XaxpyComplexSingle, database::XaxpyComplexDouble,
-      database::XdotHalf, database::XdotSingle, database::XdotDouble, database::XdotComplexSingle, database::XdotComplexDouble,
-      database::XgemvHalf, database::XgemvSingle, database::XgemvDouble, database::XgemvComplexSingle, database::XgemvComplexDouble,
-      database::XgemvFastHalf, database::XgemvFastSingle, database::XgemvFastDouble, database::XgemvFastComplexSingle, database::XgemvFastComplexDouble,
-      database::XgemvFastRotHalf, database::XgemvFastRotSingle, database::XgemvFastRotDouble, database::XgemvFastRotComplexSingle, database::XgemvFastRotComplexDouble,
-      database::XgerHalf, database::XgerSingle, database::XgerDouble, database::XgerComplexSingle, database::XgerComplexDouble,
-      database::XgemmHalf, database::XgemmSingle, database::XgemmDouble, database::XgemmComplexSingle, database::XgemmComplexDouble,
-      database::XgemmDirectHalf, database::XgemmDirectSingle, database::XgemmDirectDouble, database::XgemmDirectComplexSingle, database::XgemmDirectComplexDouble,
-      database::CopyHalf, database::CopySingle, database::CopyDouble, database::CopyComplexSingle, database::CopyComplexDouble,
-      database::PadHalf, database::PadSingle, database::PadDouble, database::PadComplexSingle, database::PadComplexDouble,
-      database::TransposeHalf, database::TransposeSingle, database::TransposeDouble, database::TransposeComplexSingle, database::TransposeComplexDouble,
-      database::PadtransposeHalf, database::PadtransposeSingle, database::PadtransposeDouble, database::PadtransposeComplexSingle, database::PadtransposeComplexDouble,
-      database::InvertHalf, database::InvertSingle, database::InvertDouble, database::InvertComplexSingle, database::InvertComplexDouble,
-      database::GemmRoutineHalf, database::GemmRoutineSingle, database::GemmRoutineDouble, database::GemmRoutineComplexSingle, database::GemmRoutineComplexDouble,
-      database::TrsvRoutineHalf, database::TrsvRoutineSingle, database::TrsvRoutineDouble, database::TrsvRoutineComplexSingle, database::TrsvRoutineComplexDouble
-  };
+  // Initializes the static variable on first use. At this point we are sure all global variables are initialized
+  if (database.size() == 0) {
+    database = std::vector<database::DatabaseEntry>{
+        database::XaxpyHalf, database::XaxpySingle, database::XaxpyDouble, database::XaxpyComplexSingle, database::XaxpyComplexDouble,
+        database::XdotHalf, database::XdotSingle, database::XdotDouble, database::XdotComplexSingle, database::XdotComplexDouble,
+        database::XgemvHalf, database::XgemvSingle, database::XgemvDouble, database::XgemvComplexSingle, database::XgemvComplexDouble,
+        database::XgemvFastHalf, database::XgemvFastSingle, database::XgemvFastDouble, database::XgemvFastComplexSingle, database::XgemvFastComplexDouble,
+        database::XgemvFastRotHalf, database::XgemvFastRotSingle, database::XgemvFastRotDouble, database::XgemvFastRotComplexSingle, database::XgemvFastRotComplexDouble,
+        database::XgerHalf, database::XgerSingle, database::XgerDouble, database::XgerComplexSingle, database::XgerComplexDouble,
+        database::XgemmHalf, database::XgemmSingle, database::XgemmDouble, database::XgemmComplexSingle, database::XgemmComplexDouble,
+        database::XgemmDirectHalf, database::XgemmDirectSingle, database::XgemmDirectDouble, database::XgemmDirectComplexSingle, database::XgemmDirectComplexDouble,
+        database::CopyHalf, database::CopySingle, database::CopyDouble, database::CopyComplexSingle, database::CopyComplexDouble,
+        database::PadHalf, database::PadSingle, database::PadDouble, database::PadComplexSingle, database::PadComplexDouble,
+        database::TransposeHalf, database::TransposeSingle, database::TransposeDouble, database::TransposeComplexSingle, database::TransposeComplexDouble,
+        database::PadtransposeHalf, database::PadtransposeSingle, database::PadtransposeDouble, database::PadtransposeComplexSingle, database::PadtransposeComplexDouble,
+        database::InvertHalf, database::InvertSingle, database::InvertDouble, database::InvertComplexSingle, database::InvertComplexDouble,
+        database::GemmRoutineHalf, database::GemmRoutineSingle, database::GemmRoutineDouble, database::GemmRoutineComplexSingle, database::GemmRoutineComplexDouble,
+        database::TrsvRoutineHalf, database::TrsvRoutineSingle, database::TrsvRoutineDouble, database::TrsvRoutineComplexSingle, database::TrsvRoutineComplexDouble
+    };
+  }
 
   // Finds device information
   const auto device_type = GetDeviceType(device);
diff --git a/src/database/database.hpp b/src/database/database.hpp
index de4306bc..8e53e013 100644
--- a/src/database/database.hpp
+++ b/src/database/database.hpp
@@ -35,7 +35,7 @@ class Database {
   static const std::string kDeviceVendorAll;
 
   // The database consists of separate database entries, stored together in a vector
-  std::vector<database::DatabaseEntry> database;
+  static std::vector<database::DatabaseEntry> database;
 
   // Database for a special case: Apple CPUs support limited number of threads
   static const std::vector<database::DatabaseEntry> apple_cpu_fallback;