Update README.md

README.md

@@ -10,87 +10,97 @@ Example usage:
 Define a function that executes the code to be measured a
 specified number of times:
 
-    static void BM_StringCreation(benchmark::State& state) {
-      while (state.KeepRunning())
-        std::string empty_string;
-    }
-    // Register the function as a benchmark
-    BENCHMARK(BM_StringCreation);
-
-    // Define another benchmark
-    static void BM_StringCopy(benchmark::State& state) {
-      std::string x = "hello";
-      while (state.KeepRunning())
-        std::string copy(x);
-    }
-    BENCHMARK(BM_StringCopy);
-
-    // Augment the main() program to invoke benchmarks if specified
-    // via the --benchmarks command line flag.  E.g.,
-    //       my_unittest --benchmark_filter=all
-    //       my_unittest --benchmark_filter=BM_StringCreation
-    //       my_unittest --benchmark_filter=String
-    //       my_unittest --benchmark_filter='Copy|Creation'
-    int main(int argc, char** argv) {
-      benchmark::Initialize(&argc, argv);
-      benchmark::RunSpecifiedBenchmarks();
-      return 0;
-    }
+```c++
+static void BM_StringCreation(benchmark::State& state) {
+  while (state.KeepRunning())
+    std::string empty_string;
+}
+// Register the function as a benchmark
+BENCHMARK(BM_StringCreation);
+
+// Define another benchmark
+static void BM_StringCopy(benchmark::State& state) {
+  std::string x = "hello";
+  while (state.KeepRunning())
+    std::string copy(x);
+}
+BENCHMARK(BM_StringCopy);
+
+// Augment the main() program to invoke benchmarks if specified
+// via the --benchmarks command line flag.  E.g.,
+//       my_unittest --benchmark_filter=all
+//       my_unittest --benchmark_filter=BM_StringCreation
+//       my_unittest --benchmark_filter=String
+//       my_unittest --benchmark_filter='Copy|Creation'
+int main(int argc, char** argv) {
+  benchmark::Initialize(&argc, argv);
+  benchmark::RunSpecifiedBenchmarks();
+  return 0;
+}
+```
 
 Sometimes a family of microbenchmarks can be implemented with
 just one routine that takes an extra argument to specify which
 one of the family of benchmarks to run.  For example, the following
 code defines a family of microbenchmarks for measuring the speed
-of memcpy() calls of different lengths:
-
-    static void BM_memcpy(benchmark::State& state) {
-      char* src = new char[state.range_x()]; char* dst = new char[state.range_x()];
-      memset(src, 'x', state.range_x());
-      while (state.KeepRunning()) {
-        memcpy(dst, src, state.range_x());
-      benchmark::SetBenchmarkBytesProcessed(
-          int64_t(state.iterations) * int64_t(state.range_x()));
-      delete[] src;
-      delete[] dst;
-    }
-    BENCHMARK(BM_memcpy)->Arg(8)->Arg(64)->Arg(512)->Arg(1<<10)->Arg(8<<10);
+of `memcpy()` calls of different lengths:
+
+```c++
+static void BM_memcpy(benchmark::State& state) {
+  char* src = new char[state.range_x()]; char* dst = new char[state.range_x()];
+  memset(src, 'x', state.range_x());
+  while (state.KeepRunning()) {
+    memcpy(dst, src, state.range_x());
+  benchmark::SetBenchmarkBytesProcessed(
+      int64_t(state.iterations) * int64_t(state.range_x()));
+  delete[] src;
+  delete[] dst;
+}
+BENCHMARK(BM_memcpy)->Arg(8)->Arg(64)->Arg(512)->Arg(1<<10)->Arg(8<<10);
+```
 
 The preceding code is quite repetitive, and can be replaced with the
 following short-hand.  The following invocation will pick a few
 appropriate arguments in the specified range and will generate a
 microbenchmark for each such argument.
 
-    BENCHMARK(BM_memcpy)->Range(8, 8<<10);
+```c++
+BENCHMARK(BM_memcpy)->Range(8, 8<<10);
+```
 
 You might have a microbenchmark that depends on two inputs.  For
 example, the following code defines a family of microbenchmarks for
 measuring the speed of set insertion.
 
-    static void BM_SetInsert(benchmark::State& state) {
-      while (state.KeepRunning()) {
-        state.PauseTiming();
-        std::set<int> data = ConstructRandomSet(state.range_x());
-        state.ResumeTiming();
-        for (int j = 0; j < state.rangeY; ++j)
-          data.insert(RandomNumber());
-      }
-    }
-    BENCHMARK(BM_SetInsert)
-        ->ArgPair(1<<10, 1)
-        ->ArgPair(1<<10, 8)
-        ->ArgPair(1<<10, 64)
-        ->ArgPair(1<<10, 512)
-        ->ArgPair(8<<10, 1)
-        ->ArgPair(8<<10, 8)
-        ->ArgPair(8<<10, 64)
-        ->ArgPair(8<<10, 512);
+```c++
+static void BM_SetInsert(benchmark::State& state) {
+  while (state.KeepRunning()) {
+    state.PauseTiming();
+    std::set<int> data = ConstructRandomSet(state.range_x());
+    state.ResumeTiming();
+    for (int j = 0; j < state.rangeY; ++j)
+      data.insert(RandomNumber());
+  }
+}
+BENCHMARK(BM_SetInsert)
+    ->ArgPair(1<<10, 1)
+    ->ArgPair(1<<10, 8)
+    ->ArgPair(1<<10, 64)
+    ->ArgPair(1<<10, 512)
+    ->ArgPair(8<<10, 1)
+    ->ArgPair(8<<10, 8)
+    ->ArgPair(8<<10, 64)
+    ->ArgPair(8<<10, 512);
+```
 
 The preceding code is quite repetitive, and can be replaced with
 the following short-hand.  The following macro will pick a few
 appropriate arguments in the product of the two specified ranges
 and will generate a microbenchmark for each such pair.
 
-    BENCHMARK(BM_SetInsert)->RangePair(1<<10, 8<<10, 1, 512);
+```c++
+BENCHMARK(BM_SetInsert)->RangePair(1<<10, 8<<10, 1, 512);
+```
 
 For more complex patterns of inputs, passing a custom function
 to Apply allows programmatic specification of an
@@ -98,48 +108,54 @@ arbitrary set of arguments to run the microbenchmark on.
 The following example enumerates a dense range on one parameter,
 and a sparse range on the second.
 
-    static benchmark::internal::Benchmark* CustomArguments(
-        benchmark::internal::Benchmark* b) {
-      for (int i = 0; i <= 10; ++i)
-        for (int j = 32; j <= 1024*1024; j *= 8)
-          b = b->ArgPair(i, j);
-      return b;
-    }
-    BENCHMARK(BM_SetInsert)->Apply(CustomArguments);
+```c++
+static benchmark::internal::Benchmark* CustomArguments(
+    benchmark::internal::Benchmark* b) {
+  for (int i = 0; i <= 10; ++i)
+    for (int j = 32; j <= 1024*1024; j *= 8)
+      b = b->ArgPair(i, j);
+  return b;
+}
+BENCHMARK(BM_SetInsert)->Apply(CustomArguments);
+```
 
 Templated microbenchmarks work the same way:
 Produce then consume 'size' messages 'iters' times
 Measures throughput in the absence of multiprogramming.
 
-    template <class Q> int BM_Sequential(benchmark::State& state) {
-      Q q;
-      typename Q::value_type v;
-      while (state.KeepRunning()) {
-        for (int i = state.range_x(); i--; )
-          q.push(v);
-        for (int e = state.range_x(); e--; )
-          q.Wait(&v);
-      }
-      // actually messages, not bytes:
-      state.SetBytesProcessed(
-          static_cast<int64_t>(state.iterations())*state.range_x());
-    }
-    BENCHMARK_TEMPLATE(BM_Sequential, WaitQueue<int>)->Range(1<<0, 1<<10);
+```c++
+template <class Q> int BM_Sequential(benchmark::State& state) {
+  Q q;
+  typename Q::value_type v;
+  while (state.KeepRunning()) {
+    for (int i = state.range_x(); i--; )
+      q.push(v);
+    for (int e = state.range_x(); e--; )
+      q.Wait(&v);
+  }
+  // actually messages, not bytes:
+  state.SetBytesProcessed(
+      static_cast<int64_t>(state.iterations())*state.range_x());
+}
+BENCHMARK_TEMPLATE(BM_Sequential, WaitQueue<int>)->Range(1<<0, 1<<10);
+```
 
 In a multithreaded test, it is guaranteed that none of the threads will start
 until all have called KeepRunning, and all will have finished before KeepRunning
 returns false. As such, any global setup or teardown you want to do can be
 wrapped in a check against the thread index:
 
-    static void BM_MultiThreaded(benchmark::State& state) {
-      if (state.thread_index == 0) {
-        // Setup code here.
-      }
-      while (state.KeepRunning()) {
-        // Run the test as normal.
-      }
-      if (state.thread_index == 0) {
-        // Teardown code here.
-      }
-    }
-    BENCHMARK(BM_MultiThreaded)->Threads(2);
+```c++
+static void BM_MultiThreaded(benchmark::State& state) {
+  if (state.thread_index == 0) {
+    // Setup code here.
+  }
+  while (state.KeepRunning()) {
+    // Run the test as normal.
+  }
+  if (state.thread_index == 0) {
+    // Teardown code here.
+  }
+}
+BENCHMARK(BM_MultiThreaded)->Threads(2);
+```