added benchmark submodule

benchmark/benchmark_mat.cpp

@@ -1,31 +1,28 @@
 //
 // Created by Vlad on 9/17/2025.
 //
-#include <gtest/gtest.h>
+#include <benchmark/benchmark.h>
+
 #include <omath/omath.hpp>
 #include <chrono>
 #include <print>
 
 using namespace omath;
-TEST(MatPerformanceTest, Mutl)
+
+static void BM_MatMutiplication(benchmark::State& state)
 {
     using mat_type = Mat<128, 128, float, MatStoreType::COLUMN_MAJOR>;
     mat_type a;
     mat_type b;
     a.set(3.f);
     b.set(7.f);
-    constexpr int iters = 1000;
-    float acum_time = 0.f;
-    mat_type c;
-    for (std::size_t i = 0 ; i < iters; i++)
+
+
+    for (auto _ : state)
     {
-        const auto start = std::chrono::high_resolution_clock::now();
-        c = a * b;
-        const auto end = std::chrono::high_resolution_clock::now();
-
-        const auto time = std::chrono::duration_cast<std::chrono::microseconds>(end - start).count();
-
-        acum_time += static_cast<float>(time);
+        std::ignore = a * b;
     }
-    std::print("Elapsed: {}, \n\n\n", acum_time / iters, c);
-}
+}
+
+BENCHMARK(BM_MatMutiplication);
+BENCHMARK_MAIN();