ci: add macOS walltime job running fib benchmark for flamegraph testing

Author: not-matthias

.github/workflows/ci.yml

@@ -64,6 +64,9 @@ jobs:
             runner: "ubuntu-latest"
           - codspeed-mode: "walltime"
             runner: "codspeed-macro"
+          - codspeed-mode: "walltime"
+            runner: "macos-latest"
+            benchmark-filter: "BM_FibonacciRecursive_Darwin"
           - codspeed-mode: "off"
             runner: "ubuntu-latest"
     runs-on: ${{ matrix.runner }}
@@ -93,7 +96,7 @@ jobs:
         if: matrix.codspeed-mode != 'off'
         with:
           mode: ${{ matrix.codspeed-mode }}
-          run: examples/google_benchmark_cmake/build/benchmark_example
+          run: examples/google_benchmark_cmake/build/benchmark_example --benchmark_filter=${{ matrix.benchmark-filter || '.*' }}
 
   bazel-integration-tests:
     strategy:

examples/google_benchmark_cmake/fibonacci_bench.hpp

@@ -16,6 +16,17 @@ static void BM_FibonacciRecursive(benchmark::State& state) {
 }
 BENCHMARK(BM_FibonacciRecursive)->Arg(35)->MinTime(5);
 
+#ifdef __APPLE__
+static void BM_FibonacciRecursive_Darwin(benchmark::State& state) {
+  int n = static_cast<int>(state.range(0));
+  for (auto _ : state) {
+    uint64_t result = fibonacci_recursive(n);
+    benchmark::DoNotOptimize(result);
+  }
+}
+BENCHMARK(BM_FibonacciRecursive_Darwin)->Arg(35)->MinTime(5);
+#endif
+
 static uint64_t fibonacci_iterative(int n) {
   if (n <= 1) return n;