Add transform.cpp std::transform test.

src/transform.cpp

@@ -0,0 +1,55 @@
+/*/true;A="$(readlink -f -- "$0")";g++ --std=c++20 -O3 -Wall -Wextra -lbenchmark -o "$A.bin" "$A"&&"$A.bin" "$@";E=$?;rm "$A.bin";exit $E #*/
+#include <algorithm>
+#include <benchmark/benchmark.h>
+#include <string>
+#include <sysexits.h>
+
+
+const char* data = "Hello world, to be or not to be a long string, that is the question!";
+
+static void algorithm_lowercase_my(benchmark::State& state) {
+    for (auto _ : state) {  // Code inside this loop is measured repeatedly
+        std::string name = data;
+        std::transform(name.cbegin(), name.cend(), name.begin(), [](char c) noexcept {
+            return (c >= 'a' && c <= 'z') ? c = c - 'a' + 'A' : c;
+        });
+        benchmark::DoNotOptimize(name);  // Make sure the variable is not optimized away by compiler
+    }
+}
+BENCHMARK(algorithm_lowercase_my);  // Register the function as a benchmark
+
+static void loop_lowercase_my(benchmark::State& state) {
+    for (auto _ : state) {  // Code before the loop is not measured
+        std::string name = data;
+        for (char& c : name) {
+            if (c >= 'a' && c <= 'z') {
+                c = c - 'a' + 'A';
+            }
+        }
+        benchmark::DoNotOptimize(name);  // Make sure the variable is not optimized away by compiler
+    }
+}
+BENCHMARK(loop_lowercase_my);  // Register the function as a benchmark
+
+
+static void algorithm_lowercase_toupper(benchmark::State& state) {
+    for (auto _ : state) {  // Code inside this loop is measured repeatedly
+        std::string name = data;
+        std::transform(name.cbegin(), name.cend(), name.begin(), [](char c) noexcept {
+            return std::toupper(static_cast<unsigned char>(c));
+        });
+        benchmark::DoNotOptimize(name);  // Make sure the variable is not optimized away by compiler
+    }
+}
+BENCHMARK(algorithm_lowercase_toupper);  // Register the function as a benchmark
+
+
+int main(int argc, char** argv) {
+    benchmark::Initialize(&argc, argv);
+    if (benchmark::ReportUnrecognizedArguments(argc, argv)) {
+        return EX_USAGE;
+    }
+
+    benchmark::RunSpecifiedBenchmarks();
+    return EX_OK;
+}