Integration openmp

.github/workflows/cmake-multi-platform.yml

@@ -79,7 +79,7 @@ jobs:
       run: ${{github.workspace}}/build/main
 
     - name: Run example
-      run: ${{github.workspace}}/build/simple
+      run: ${{github.workspace}}/build/matrix_eigen
 
     # - name: Test
     #   working-directory: ${{ steps.strings.outputs.build-output-dir }}

CMakeLists.txt

@@ -10,20 +10,32 @@ set(CMAKE_CXX_FLAGS_DEBUG "-g -fsanitize=address,undefined")
 
 # include_directories(include)
 
-# OpenMP
-find_package(OpenMP)
-if(OpenMP_CXX_FOUND)
-    set(LINK_LIBS ${LINK_LIBS} ${OpenMP_CXX_LIBRARIES})
-endif()
-
 # Eigen
 find_package(Eigen3 3.3 REQUIRED NO_MODULE)
 set(LINK_LIBS ${LINK_LIBS} Eigen3::Eigen)
 
-
 # Executables
 add_executable(main examples/main.cpp) # create an executable using the specified file
 target_link_libraries(main PUBLIC ${LINK_LIBS})
 
-add_executable(simple examples/simple.cpp) # create an executable using the specified file
-target_link_libraries(simple PUBLIC ${LINK_LIBS})
+add_executable(matrix_eigen examples/matrix_eigen.cpp) # create an executable using the specified file
+target_link_libraries(matrix_eigen PUBLIC ${LINK_LIBS})
+
+
+# OpenMP activation
+option(USE_OPENMP "Enable OpenMP support" OFF)
+
+# If ON search for OpenMP 
+if(USE_OPENMP)
+    find_package(OpenMP REQUIRED)
+    if(OpenMP_CXX_FOUND)
+        add_executable(loop_omp examples/loop_omp.cpp) # create an executable using the specified file
+        target_compile_options(loop_omp PUBLIC ${OpenMP_CXX_FLAGS})
+        target_link_libraries(loop_omp PUBLIC ${OpenMP_CXX_FLAGS})
+        message(STATUS "OpenMP flags added for GCC/Clang: ${OpenMP_CXX_FLAGS}")
+    else()
+        message(FATAL_ERROR "OpenMP was requested but could not be found.")
+    endif()
+else()
+    message(STATUS "OpenMP support disabled")
+endif()

README.md

@@ -60,6 +60,12 @@ cmake -S . -B build/ -D CMAKE_BUILD_TYPE=Release
 cmake --build build/
 ```
 
+### Configure a release with OpenMP
+```bash
+cmake -S . -B build -DUSE_OPENMP=ON
+cmake --build build
+```
+
 ## Troubleshooting
 
 ## Reference

examples/loop_omp.cpp

@@ -0,0 +1,29 @@
+#include <iostream>
+#include <vector>
+#include <omp.h>
+
+int main() {
+    // Initialisation d'un grand tableau pour simuler une charge de travail
+    const int N = 1000000;
+    std::vector<int> array(N, 1); // Crée un tableau avec des valeurs de 1
+    int sum = 0;
+
+    // Mesurer le temps avant le calcul
+    double start_time = omp_get_wtime();
+
+    // Début de la région parallèle
+    #pragma omp parallel for reduction(+:sum)
+    for (int i = 0; i < N; ++i) {
+        sum += array[i];
+    }
+
+    // Mesurer le temps après le calcul
+    double end_time = omp_get_wtime();
+
+    // Résultats
+    std::cout << "La somme est: " << sum << std::endl;
+    std::cout << "Temps d'exécution avec OpenMP: " << (end_time - start_time) << " secondes" << std::endl;
+
+    return 0;
+}
+