[benchmarks] Move libcxx's fork of google/benchmark and llvm/utils' under third-party

[mtrofin]

Summary

This change:

• moves the libcxx copy of google/benchmark to third-party/benchmkark
• points the 2 uses of the library (libcxx and llvm/utils) to this copy

We picked the licxx copy because it is the most up to date.

[ldionne]

I like this a lot in spirit, thanks!

However, we are trying to decouple the runtimes (which include libc++) from everything in <monorepo>/llvm, and placing the GoogleBenchmark library inside <monorepo>/llvm somewhat goes against that. Would it make sense to try to find a place in LLVM where we can put third-party libraries like that? IMO it would be sensible to avoid tying them to <monorepo>/llvm just like we should avoid tying them to any other specific sub-project under the LLVM Foundation. WDYT?

[Meinersbur]

@ldionne What is your concrete proposal? Requiring Google Benchmark pre-installed on the host?

I think <root>/llvm is different in that it is not a subproject but contains core and supporting infrastructure (such as <root>/llvm/cmake/Modules, llvm-lit etc). Google Benchmark would be one of that. I don't think we should reject patches that just follow the status quo without having a plan what the future direction should be.

[mtrofin]

In D112012#3072064, @Meinersbur wrote:

@ldionne What is your concrete proposal? Requiring Google Benchmark pre-installed on the host?

I think <root>/llvm is different in that it is not a subproject but contains core and supporting infrastructure (such as <root>/llvm/cmake/Modules, llvm-lit etc). Google Benchmark would be one of that. I don't think we should reject patches that just follow the status quo without having a plan what the future direction should be.

@ldionne @Meinersbur - trying to move this forward - if libcxx can't depend on llvm/ stuff, how about having a llvm/third-party common dir, would that work? (I'd want to circle this back to the thread discussing google-benchmark consolidation, but wanted to get a quick smoke test.)

[Meinersbur]

In D112012#3078815, @mtrofin wrote:

@ldionne @Meinersbur - trying to move this forward - if libcxx can't depend on llvm/ stuff, how about having a llvm/third-party common dir, would that work?

At least it would also need changes in buidbot/zorg -- currently, changes in directories not related to any subproject will not trigger a new build.

[mtrofin]

moved to third_party

since the change is large because of the moved files, the important changes are in:

llvm/CMakeLists.txt
third_party/CMakeLists.txt (added)
llvm/cmake/modules/AddLLVM.cmake
libcxx/benchmarks/CMakeLists.txt

[ldionne]

In D112012#3072064, @Meinersbur wrote:

@ldionne What is your concrete proposal? Requiring Google Benchmark pre-installed on the host?

As I said in my comment, I was suggesting that we put it in the monorepo, but just not under llvm/. You current proposal for third-party sounds reasonable to me.

I think <root>/llvm is different in that it is not a subproject but contains core and supporting infrastructure (such as <root>/llvm/cmake/Modules, llvm-lit etc).

This is historical, back when we would check out all the sub projects under llvm/projects. It makes no sense at all to store the common CMake infrastructure or lit under llvm/ anymore, either. I'm not suggesting we change the whole world right now, I'm just saying that if we are going to move stuff around, we might as well do it correctly from the start.

I don't think we should reject patches that just follow the status quo without having a plan what the future direction should be.

From the libc++ perspective, the patch before moving to third-party/ was adding a new hard dependency from libcxx/ to llvm/, which is precisely what we're trying to move away from, hence my question and my request for changes.

IMO this patch looks great now, if everybody is happy with having a top-level third-party. I think it makes a lot of sense to have that, but I'm looking for other folks on this review to chime in. If we want to establish this as the new "canonical" place to store third-party dependencies, perhaps a post on the various lists would be a good idea to get people's attention? I'm not requesting it, just suggesting. Personally I'm happy with this change as-is.

However, we do need to fix the CI for libc++. Since you're moving the library to another place, we'll need to adjust the paths to it in libcxx/. I think this should be sufficient:

diff --git a/libcxx/benchmarks/CMakeLists.txt b/libcxx/benchmarks/CMakeLists.txt
index cad880858a78..91aadc864907 100644
--- a/libcxx/benchmarks/CMakeLists.txt
+++ b/libcxx/benchmarks/CMakeLists.txt
@@ -35,7 +35,7 @@ ExternalProject_Add(google-benchmark-libcxx
         EXCLUDE_FROM_ALL ON
         DEPENDS cxx cxx-headers
         PREFIX benchmark-libcxx
-        SOURCE_DIR ${LIBCXX_SOURCE_DIR}/utils/google-benchmark
+        SOURCE_DIR ${LIBCXX_SOURCE_DIR}/../third-party/google-benchmark
         INSTALL_DIR ${CMAKE_CURRENT_BINARY_DIR}/benchmark-libcxx
         CMAKE_CACHE_ARGS
           -DCMAKE_C_COMPILER:STRING=${CMAKE_C_COMPILER}
@@ -60,7 +60,7 @@ if (LIBCXX_BENCHMARK_NATIVE_STDLIB)
   ExternalProject_Add(google-benchmark-native
         EXCLUDE_FROM_ALL ON
         PREFIX benchmark-native
-        SOURCE_DIR ${LIBCXX_SOURCE_DIR}/utils/google-benchmark
+        SOURCE_DIR ${LIBCXX_SOURCE_DIR}/../third-party/google-benchmark
         INSTALL_DIR ${CMAKE_CURRENT_BINARY_DIR}/benchmark-native
         CMAKE_CACHE_ARGS
           -DCMAKE_C_COMPILER:STRING=${CMAKE_C_COMPILER}

I suspect you need similar changes elsewhere in LLVM.

Marking as approved in case I don't see this again for a while, but please don't submit until (at least) the libc++ CI is green.

[ldionne]

In D112012#3106549, @ldionne wrote:

However, we do need to fix the CI for libc++. Since you're moving the library to another place, we'll need to adjust the paths to it in libcxx/. I think this should be sufficient:
[...]

Oh, sorry, I hadn't seen your changes to libcxx/benchmark/CMakeLists.txt. The issue now is that LLVM_THIRD_PARTY_DIR is only set in llvm/CMakeLists.txt. However, the runtimes don't use that directory anymore (in fact building the runtimes using llvm/CMakeLists.txt is deprecated). You'd have to set LLVM_THIRD_PARTY_DIR in runtimes/CMakeLists.txt.

[mtrofin]

In D112012#3106555, @ldionne wrote:

In D112012#3106549, @ldionne wrote:

However, we do need to fix the CI for libc++. Since you're moving the library to another place, we'll need to adjust the paths to it in libcxx/. I think this should be sufficient:
[...]

Oh, sorry, I hadn't seen your changes to libcxx/benchmark/CMakeLists.txt. The issue now is that LLVM_THIRD_PARTY_DIR is only set in llvm/CMakeLists.txt. However, the runtimes don't use that directory anymore (in fact building the runtimes using llvm/CMakeLists.txt is deprecated). You'd have to set LLVM_THIRD_PARTY_DIR in runtimes/CMakeLists.txt.

Ah, I see - so in runtimes/CMakeLists.txt, if LLVM_THIRD_PARTY_DIR isn't set, then we set it there to ../third_party or something of that sort, correct?

[mtrofin]

added def for LLVM_THIRD_PARTY_DIR in runtimes

[mtrofin]

@ldionne - is there anything else I need to do to this change? Thanks!

[ldionne]

To fix the CI, you'll want to rebase onto main once I've landed D113503. That patch removes support for the benchmarks under the libc++ standalone build, since this patch breaks that use case. I think it's fine though, we are trying to get rid of the standalone build anyway, it's just a matter of time.

llvm/CMakeLists.txt

70

This is entirely new behavior, and I don't understand why we're doing this as part of this patch. IMO this patch should only be moving stuff around, period. If we then want to start considering the third-party projects as a "project" we can enable with LLVM_ENABLE_PROJECTS, we should tackle it as a separate effort (and frankly it's not clear to me that would fly).

Also, when you make changes like this as part of a much larger change, it is often a good idea to call them out to make sure reviewers see them.

1182–1192

This is the minimal change. Just move stuff around and point to the new directory from llvm/ and from runtimes/ + libcxx/benchmarks. Everything else should be in a different patch since that's a meaningful change.

runtimes/CMakeLists.txt

39 ↗

(On Diff #385507)

Why the if (NOT DEFINED LLVM_THIRD_PARTY_DIR)? If we can set it unconditionally, we should because it avoid giving the impression that folks can set it however they want.

[mtrofin]

no need to make third-party a project

llvm/CMakeLists.txt

70

Huh, I thought this was the approach to follow for adding subprojects that are peers (dir structure) to llvm. Probably got confused by 'peer dirs' and 'projects' as identical concepts - in any case, fixed.

1182–1192

I assume the 'everything else' refers to the making of third-party as a project, which is moot now?

[ldionne]

Note that D113503 has landed now, so you should rebase onto main.

llvm/CMakeLists.txt

996

I don't understand why this is needed.

llvm/cmake/modules/AddLLVM.cmake

1528

I don't understand why this is needed.

[mtrofin]

rebased

[mtrofin]

llvm/CMakeLists.txt

996

not needed

llvm/cmake/modules/AddLLVM.cmake

1528

I thought it was needed to make sure the library is built, but I suppose the line below addresses that.

[mtrofin]

removed unneeded lines

[ldionne]

LGTM. Now that seems like a minimal change!

Thanks! You can ignore the libc++ CI which failed, it failed due to an issue that has already been resolved.

[sivachandra]

FYI: The libcxx copy and llvm/utils copy were not identical. So, the libc benchmarks are currently broken because of that. I have added an inline comment to show the single difference we are seeing. We can fix forward.

llvm/utils/benchmark/include/benchmark/benchmark.h

1236

The definition of this struct is not the same as the one in the libcxx copy.

[mtrofin]

Oh! Huh, missed that. Probably my ninja check-all didn’t build the
benchmarks. I’ll patch shortly. Sorry for the lapse.

[haowei]

This change broke Fuchsia's linux and mac clang builder. Failed build can be seen at: https://ci.chromium.org/ui/p/fuchsia/builders/toolchain.ci/clang-linux-x64/b8830380874445931681/overview
Could you revert the change if the fix will take a while? Thanks.

[sivachandra]

In D112012#3136155, @mtrofin wrote:

Oh! Huh, missed that. Probably my ninja check-all didn’t build the
benchmarks. I’ll patch shortly. Sorry for the lapse.

I have already fixed the libc build.

[mtrofin]

Done

[mtrofin]

In D112012#3136264, @sivachandra wrote:

In D112012#3136155, @mtrofin wrote:

Oh! Huh, missed that. Probably my ninja check-all didn’t build the
benchmarks. I’ll patch shortly. Sorry for the lapse.

I have already fixed the libc build.

Oh - thanks.

(For some reason I'm getting messages out of order) should we revert though your fix until I reland this - the revert due to Fuchsia's build failure seems to be due to the way they ingest CMakeLists.txt

[mtrofin]

In D112012#3136235, @haowei wrote:

This change broke Fuchsia's linux and mac clang builder. Failed build can be seen at: https://ci.chromium.org/ui/p/fuchsia/builders/toolchain.ci/clang-linux-x64/b8830380874445931681/overview
Could you revert the change if the fix will take a while? Thanks.

@ldionne @phosek I think the Fuchsia build failure is because they ingest the libcxx CMakeLists.txt directly, without going through the one in runtimes/. Should we reconsider setting LLVM_THIRD_PARTY_DIR in runtimes/CMakeLists.txt, and, instead, set it separately in libcxx and libc's CMakeLists?

or, is the way Fuchsia is ingesting libcxx's CMakeLists incorrect?

[phosek]

In D112012#3136277, @mtrofin wrote:

In D112012#3136235, @haowei wrote:

This change broke Fuchsia's linux and mac clang builder. Failed build can be seen at: https://ci.chromium.org/ui/p/fuchsia/builders/toolchain.ci/clang-linux-x64/b8830380874445931681/overview
Could you revert the change if the fix will take a while? Thanks.

@ldionne @phosek I think the Fuchsia build failure is because they ingest the libcxx CMakeLists.txt directly, without going through the one in runtimes/. Should we reconsider setting LLVM_THIRD_PARTY_DIR in runtimes/CMakeLists.txt, and, instead, set it separately in libcxx and libc's CMakeLists?

or, is the way Fuchsia is ingesting libcxx's CMakeLists incorrect?

That's not an issue with the Fuchsia build, it's an issue with the libFuzzer build which we include in our toolchain build.

libFuzzer on Linux and Fuchsia uses a private copy of libc++ and that build still build still goes through libcxx/CMakeLists.txt, see:

https://github.com/llvm/llvm-project/blob/01510ac08474a6c4beae033794b71b6b5ab1e89d/compiler-rt/lib/fuzzer/CMakeLists.txt#L160
https://github.com/llvm/llvm-project/blob/01510ac08474a6c4beae033794b71b6b5ab1e89d/compiler-rt/cmake/Modules/AddCompilerRT.cmake#L546
https://github.com/llvm/llvm-project/blob/01510ac08474a6c4beae033794b71b6b5ab1e89d/compiler-rt/cmake/Modules/CustomLibcxx/CMakeLists.txt

We need to change it to use runtimes/CMakeLists.txt instead.

[mstorsjo]

This broke building for MinGW, due to a local change (from rG948ce4e6edec6ad3cdf1911fc3e8e9569140d4ff that never was upstreamed) that was dropped as part of the move. I've submitted that fix upstream now in https://github.com/google/benchmark/pull/1302, and I filed D115434 to get it applied on the new location.

This also showed another brittleness in the benchmark library, as it's built with -Werror by default (in non-MSVC builds). As the benchmark library is built by default when building all of LLVM, building it with -Werror feels excessive and brittle. -Werror was commented out in the original import of the benchmark library in rG0addd170ab0880941fa4089c2717f3f3a0e4e25a, but wasn't commented out in the copy in libcxx (which wasn't built by default, at least not as widely, and thus the issue wasn't noticed there).

llvm/CMakeLists.txt

 
 # Side-by-side subprojects layout: automatically set the
 # LLVM_EXTERNAL_${project}_SOURCE_DIR using LLVM_ALL_PROJECTS
 # This allows an easy way of setting up a build directory for llvm and another
 # one for llvm+clang+... using the same sources.
 set(LLVM_ALL_PROJECTS "clang;clang-tools-extra;compiler-rt;cross-project-tests;libc;libclc;libcxx;libcxxabi;libunwind;lld;lldb;mlir;openmp;polly;pstl")
 # The flang project is not yet part of "all" projects (see C++ requirements)
 set(LLVM_EXTRA_PROJECTS "flang")
+set(LLVM_THIRD_PARTY_PROJECTS "third-party")
 # List of all known projects in the mono repo
-set(LLVM_KNOWN_PROJECTS "${LLVM_ALL_PROJECTS};${LLVM_EXTRA_PROJECTS}")
+set(LLVM_KNOWN_PROJECTS "${LLVM_ALL_PROJECTS};${LLVM_EXTRA_PROJECTS};${LLVM_THIRD_PARTY_PROJECTS}")
 set(LLVM_ENABLE_PROJECTS "" CACHE STRING
   "Semicolon-separated list of projects to build (${LLVM_KNOWN_PROJECTS}), or \"all\".")
 foreach(proj ${LLVM_ENABLE_PROJECTS})
   if (NOT proj STREQUAL "all" AND NOT proj STREQUAL "llvm" AND NOT "${proj}" IN_LIST LLVM_KNOWN_PROJECTS)
      MESSAGE(FATAL_ERROR "${proj} isn't a known project: ${LLVM_KNOWN_PROJECTS}")
   endif()
 endforeach()
 foreach(proj "libcxx" "libcxxabi" "libunwind")
if (NOT "mlir" IN_LIST LLVM_ENABLE_PROJECTS)
     list(APPEND LLVM_ENABLE_PROJECTS "mlir")
   endif()
 
   if (NOT "clang" IN_LIST LLVM_ENABLE_PROJECTS)
     message(FATAL_ERROR "Clang is not enabled, but is required for the Flang driver")
   endif()
 endif()
 
+list(APPEND LLVM_ENABLE_PROJECTS ${LLVM_THIRD_PARTY_PROJECTS})
+
 # LLVM_ENABLE_PROJECTS_USED is `ON` if the user has ever used the
 # `LLVM_ENABLE_PROJECTS` CMake cache variable.  This exists for
 # several reasons:
 #
 # * As an indicator that the `LLVM_ENABLE_PROJECTS` list is now the single
 # source of truth for which projects to build. This means we will ignore user
 # supplied `LLVM_TOOL_<project>_BUILD` CMake cache variables and overwrite
 # them.

 
 # Each of them corresponds to llvm-config's.
 set(LLVM_TOOLS_BINARY_DIR ${LLVM_RUNTIME_OUTPUT_INTDIR}) # --bindir
 set(LLVM_LIBRARY_DIR      ${LLVM_LIBRARY_OUTPUT_INTDIR}) # --libdir
 set(LLVM_MAIN_SRC_DIR     ${CMAKE_CURRENT_SOURCE_DIR}  ) # --src-root
 set(LLVM_MAIN_INCLUDE_DIR ${LLVM_MAIN_SRC_DIR}/include ) # --includedir
 set(LLVM_BINARY_DIR       ${CMAKE_CURRENT_BINARY_DIR}  ) # --prefix
 
+# Expose the third party dir to other projects.
+set(LLVM_THIRD_PARTY_DIR  ${CMAKE_CURRENT_SOURCE_DIR}/../third-party)
+
 # Note: LLVM_CMAKE_DIR does not include generated files
 set(LLVM_CMAKE_DIR ${LLVM_MAIN_SRC_DIR}/cmake/modules)
 set(LLVM_EXAMPLES_BINARY_DIR ${LLVM_BINARY_DIR}/examples)
 set(LLVM_INCLUDE_DIR ${CMAKE_CURRENT_BINARY_DIR}/include)
 
 # List of all targets to be built by default:
 set(LLVM_ALL_TARGETS
   AArch64

 include(LLVMDistributionSupport)
 
 if( MINGW AND NOT "${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang" )
   # People report that -O3 is unreliable on MinGW. The traditional
   # build also uses -O2 for that reason:
   llvm_replace_compiler_option(CMAKE_CXX_FLAGS_RELEASE "-O3" "-O2")
 endif()
 
+add_llvm_external_project(third-party)
+
 # Put this before tblgen. Else we have a circular dependence.
 add_subdirectory(lib/Demangle)
 add_subdirectory(lib/Support)
 add_subdirectory(lib/TableGen)
 
 add_subdirectory(utils/TableGen)
 
 add_subdirectory(include/llvm)

 include(CoverageReport)
 
 # This allows us to deploy the Universal CRT DLLs by passing -DCMAKE_INSTALL_UCRT_LIBRARIES=ON to CMake
 if (MSVC AND CMAKE_HOST_SYSTEM_NAME STREQUAL "Windows" AND CMAKE_INSTALL_UCRT_LIBRARIES)
   include(InstallRequiredSystemLibraries)
 endif()
 
 if (LLVM_INCLUDE_BENCHMARKS)
-  # Override benchmark defaults so that when the library itself is updated these
-  # modifications are not lost.
-  set(BENCHMARK_ENABLE_TESTING OFF CACHE BOOL "Disable benchmark testing" FORCE)
-  set(BENCHMARK_ENABLE_EXCEPTIONS OFF CACHE BOOL "Disable benchmark exceptions" FORCE)
-  set(BENCHMARK_ENABLE_INSTALL OFF CACHE BOOL "Don't install benchmark" FORCE)
-  set(BENCHMARK_DOWNLOAD_DEPENDENCIES OFF CACHE BOOL "Don't download dependencies" FORCE)
-  set(BENCHMARK_ENABLE_GTEST_TESTS OFF CACHE BOOL "Disable Google Test in benchmark" FORCE)
-  # Since LLVM requires C++11 it is safe to assume that std::regex is available.
-  set(HAVE_STD_REGEX ON CACHE BOOL "OK" FORCE)
-
-  add_subdirectory(utils/benchmark)
   add_subdirectory(benchmarks)
 endif()
 
 if (LLVM_INCLUDE_UTILS AND LLVM_INCLUDE_TOOLS)
   add_subdirectory(utils/llvm-locstats)
 endif()

llvm/cmake/modules/AddLLVM.cmake

function(add_benchmark benchmark_name)
   if( NOT LLVM_BUILD_BENCHMARKS )
     set(EXCLUDE_FROM_ALL ON)
   endif()
 
   add_llvm_executable(${benchmark_name} IGNORE_EXTERNALIZE_DEBUGINFO NO_INSTALL_RPATH ${ARGN})
   set(outdir ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR})
   set_output_directory(${benchmark_name} BINARY_DIR ${outdir} LIBRARY_DIR ${outdir})
   set_property(TARGET ${benchmark_name} PROPERTY FOLDER "Utils")
+  add_dependencies(${benchmark_name} benchmark)
   target_link_libraries(${benchmark_name} PRIVATE benchmark)
 endfunction()
 
 # This function canonicalize the CMake variables passed by names
 # from CMake boolean to 0/1 suitable for passing into Python or C++,
 # in place.
 function(llvm_canonicalize_cmake_booleans)
   foreach(var ${ARGN})

llvm/utils/benchmark/include/benchmark/benchmark.h

-// Copyright 2015 Google Inc. All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// Support for registering benchmarks for functions.
-
-/* Example usage:
-// Define a function that executes the code to be measured a
-// specified number of times:
-static void BM_StringCreation(benchmark::State& state) {
-  for (auto _ : state)
-    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";
-  for (auto _ : state)
-    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(0)]; char* dst = new char[state.range(0)];
-  memset(src, 'x', state.range(0));
-  for (auto _ : state)
-    memcpy(dst, src, state.range(0));
-  state.SetBytesProcessed(int64_t(state.iterations()) *
-                          int64_t(state.range(0)));
-  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);
-
-// 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) {
-  set<int> data;
-  for (auto _ : state) {
-    state.PauseTiming();
-    data = ConstructRandomSet(state.range(0));
-    state.ResumeTiming();
-    for (int j = 0; j < state.range(1); ++j)
-      data.insert(RandomNumber());
-  }
-}
-BENCHMARK(BM_SetInsert)
-   ->Args({1<<10, 128})
-   ->Args({2<<10, 128})
-   ->Args({4<<10, 128})
-   ->Args({8<<10, 128})
-   ->Args({1<<10, 512})
-   ->Args({2<<10, 512})
-   ->Args({4<<10, 512})
-   ->Args({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)->Ranges({{1<<10, 8<<10}, {128, 512}});
-
-// For more complex patterns of inputs, passing a custom function
-// to Apply allows programmatic specification of an
-// 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 void CustomArguments(benchmark::internal::Benchmark* b) {
-  for (int i = 0; i <= 10; ++i)
-    for (int j = 32; j <= 1024*1024; j *= 8)
-      b->Args({i, j});
-}
-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;
-  for (auto _ : state) {
-    for (int i = state.range(0); i--; )
-      q.push(v);
-    for (int e = state.range(0); e--; )
-      q.Wait(&v);
-  }
-  // actually messages, not bytes:
-  state.SetBytesProcessed(
-      static_cast<int64_t>(state.iterations())*state.range(0));
-}
-BENCHMARK_TEMPLATE(BM_Sequential, WaitQueue<int>)->Range(1<<0, 1<<10);
-
-Use `Benchmark::MinTime(double t)` to set the minimum time used to run the
-benchmark. This option overrides the `benchmark_min_time` flag.
-
-void BM_test(benchmark::State& state) {
- ... body ...
-}
-BENCHMARK(BM_test)->MinTime(2.0); // Run for at least 2 seconds.
-
-In a multithreaded test, it is guaranteed that none of the threads will start
-until all have reached the loop start, and all will have finished before any
-thread exits the loop body. 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.
-  }
-  for (auto _ : state) {
-    // Run the test as normal.
-  }
-  if (state.thread_index == 0) {
-    // Teardown code here.
-  }
-}
-BENCHMARK(BM_MultiThreaded)->Threads(4);
-
-
-If a benchmark runs a few milliseconds it may be hard to visually compare the
-measured times, since the output data is given in nanoseconds per default. In
-order to manually set the time unit, you can specify it manually:
-
-BENCHMARK(BM_test)->Unit(benchmark::kMillisecond);
-*/
-
-#ifndef BENCHMARK_BENCHMARK_H_
-#define BENCHMARK_BENCHMARK_H_
-
-
-// The _MSVC_LANG check should detect Visual Studio 2015 Update 3 and newer.
-#if __cplusplus >= 201103L || (defined(_MSVC_LANG) && _MSVC_LANG >= 201103L)
-#define BENCHMARK_HAS_CXX11
-#endif
-
-#include <stdint.h>
-
-#include <algorithm>
-#include <cassert>
-#include <cstddef>
-#include <iosfwd>
-#include <string>
-#include <vector>
-#include <map>
-#include <set>
-
-#if defined(BENCHMARK_HAS_CXX11)
-#include <type_traits>
-#include <initializer_list>
-#include <utility>
-#endif
-
-#if defined(_MSC_VER)
-#include <intrin.h> // for _ReadWriteBarrier
-#endif
-
-#ifndef BENCHMARK_HAS_CXX11
-#define BENCHMARK_DISALLOW_COPY_AND_ASSIGN(TypeName) \
-  TypeName(const TypeName&);                         \
-  TypeName& operator=(const TypeName&)
-#else
-#define BENCHMARK_DISALLOW_COPY_AND_ASSIGN(TypeName) \
-  TypeName(const TypeName&) = delete;                \
-  TypeName& operator=(const TypeName&) = delete
-#endif
-
-#if defined(__GNUC__)
-#define BENCHMARK_UNUSED __attribute__((unused))
-#define BENCHMARK_ALWAYS_INLINE __attribute__((always_inline))
-#define BENCHMARK_NOEXCEPT noexcept
-#define BENCHMARK_NOEXCEPT_OP(x) noexcept(x)
-#elif defined(_MSC_VER) && !defined(__clang__)
-#define BENCHMARK_UNUSED
-#define BENCHMARK_ALWAYS_INLINE __forceinline
-#if _MSC_VER >= 1900
-#define BENCHMARK_NOEXCEPT noexcept
-#define BENCHMARK_NOEXCEPT_OP(x) noexcept(x)
-#else
-#define BENCHMARK_NOEXCEPT
-#define BENCHMARK_NOEXCEPT_OP(x)
-#endif
-#define __func__ __FUNCTION__
-#else
-#define BENCHMARK_UNUSED
-#define BENCHMARK_ALWAYS_INLINE
-#define BENCHMARK_NOEXCEPT
-#define BENCHMARK_NOEXCEPT_OP(x)
-#endif
-
-#define BENCHMARK_INTERNAL_TOSTRING2(x) #x
-#define BENCHMARK_INTERNAL_TOSTRING(x) BENCHMARK_INTERNAL_TOSTRING2(x)
-
-#if defined(__GNUC__)
-#define BENCHMARK_BUILTIN_EXPECT(x, y) __builtin_expect(x, y)
-#define BENCHMARK_DEPRECATED_MSG(msg) __attribute__((deprecated(msg)))
-#else
-#define BENCHMARK_BUILTIN_EXPECT(x, y) x
-#define BENCHMARK_DEPRECATED_MSG(msg)
-#define BENCHMARK_WARNING_MSG(msg) __pragma(message(__FILE__ "(" BENCHMARK_INTERNAL_TOSTRING(__LINE__) ") : warning note: " msg))
-#endif
-
-#if defined(__GNUC__) && !defined(__clang__)
-#define BENCHMARK_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
-#endif
-
-#ifndef __has_builtin
-#define __has_builtin(x) 0
-#endif
-
-#if defined(__GNUC__) || __has_builtin(__builtin_unreachable)
-  #define BENCHMARK_UNREACHABLE() __builtin_unreachable()
-#elif defined(_MSC_VER)
-  #define BENCHMARK_UNREACHABLE() __assume(false)
-#else
-  #define BENCHMARK_UNREACHABLE() ((void)0)
-#endif
-
-namespace benchmark {
-class BenchmarkReporter;
-
-void Initialize(int* argc, char** argv);
-
-// Report to stdout all arguments in 'argv' as unrecognized except the first.
-// Returns true there is at least on unrecognized argument (i.e. 'argc' > 1).
-bool ReportUnrecognizedArguments(int argc, char** argv);
-
-// Generate a list of benchmarks matching the specified --benchmark_filter flag
-// and if --benchmark_list_tests is specified return after printing the name
-// of each matching benchmark. Otherwise run each matching benchmark and
-// report the results.
-//
-// The second and third overload use the specified 'console_reporter' and
-//  'file_reporter' respectively. 'file_reporter' will write to the file
-//  specified
-//   by '--benchmark_output'. If '--benchmark_output' is not given the
-//  'file_reporter' is ignored.
-//
-// RETURNS: The number of matching benchmarks.
-size_t RunSpecifiedBenchmarks();
-size_t RunSpecifiedBenchmarks(BenchmarkReporter* console_reporter);
-size_t RunSpecifiedBenchmarks(BenchmarkReporter* console_reporter,
-                              BenchmarkReporter* file_reporter);
-
-// If this routine is called, peak memory allocation past this point in the
-// benchmark is reported at the end of the benchmark report line. (It is
-// computed by running the benchmark once with a single iteration and a memory
-// tracer.)
-// TODO(dominic)
-// void MemoryUsage();
-
-namespace internal {
-class Benchmark;
-class BenchmarkImp;
-class BenchmarkFamilies;
-
-void UseCharPointer(char const volatile*);
-
-// Take ownership of the pointer and register the benchmark. Return the
-// registered benchmark.
-Benchmark* RegisterBenchmarkInternal(Benchmark*);
-
-// Ensure that the standard streams are properly initialized in every TU.
-int InitializeStreams();
-BENCHMARK_UNUSED static int stream_init_anchor = InitializeStreams();
-
-}  // namespace internal
-
-
-#if (!defined(__GNUC__) && !defined(__clang__)) || defined(__pnacl__) || \
-    defined(__EMSCRIPTEN__)
-# define BENCHMARK_HAS_NO_INLINE_ASSEMBLY
-#endif
-
-
-// The DoNotOptimize(...) function can be used to prevent a value or
-// expression from being optimized away by the compiler. This function is
-// intended to add little to no overhead.
-// See: https://youtu.be/nXaxk27zwlk?t=2441
-#ifndef BENCHMARK_HAS_NO_INLINE_ASSEMBLY
-template <class Tp>
-inline BENCHMARK_ALWAYS_INLINE
-void DoNotOptimize(Tp const& value) {
-    asm volatile("" : : "r,m"(value) : "memory");
-}
-
-template <class Tp>
-inline BENCHMARK_ALWAYS_INLINE void DoNotOptimize(Tp& value) {
-#if defined(__clang__)
-  asm volatile("" : "+r,m"(value) : : "memory");
-#else
-  asm volatile("" : "+m,r"(value) : : "memory");
-#endif
-}
-
-// Force the compiler to flush pending writes to global memory. Acts as an
-// effective read/write barrier
-inline BENCHMARK_ALWAYS_INLINE void ClobberMemory() {
-  asm volatile("" : : : "memory");
-}
-#elif defined(_MSC_VER)
-template <class Tp>
-inline BENCHMARK_ALWAYS_INLINE void DoNotOptimize(Tp const& value) {
-  internal::UseCharPointer(&reinterpret_cast<char const volatile&>(value));
-  _ReadWriteBarrier();
-}
-
-inline BENCHMARK_ALWAYS_INLINE void ClobberMemory() {
-  _ReadWriteBarrier();
-}
-#else
-template <class Tp>
-inline BENCHMARK_ALWAYS_INLINE void DoNotOptimize(Tp const& value) {
-  internal::UseCharPointer(&reinterpret_cast<char const volatile&>(value));
-}
-// FIXME Add ClobberMemory() for non-gnu and non-msvc compilers
-#endif
-
-
-
-// This class is used for user-defined counters.
-class Counter {
-public:
-
-  enum Flags {
-    kDefaults   = 0,
-    // Mark the counter as a rate. It will be presented divided
-    // by the duration of the benchmark.
-    kIsRate     = 1,
-    // Mark the counter as a thread-average quantity. It will be
-    // presented divided by the number of threads.
-    kAvgThreads = 2,
-    // Mark the counter as a thread-average rate. See above.
-    kAvgThreadsRate = kIsRate|kAvgThreads
-  };
-
-  double value;
-  Flags  flags;
-
-  BENCHMARK_ALWAYS_INLINE
-  Counter(double v = 0., Flags f = kDefaults) : value(v), flags(f) {}
-
-  BENCHMARK_ALWAYS_INLINE operator double const& () const { return value; }
-  BENCHMARK_ALWAYS_INLINE operator double      & ()       { return value; }
-
-};
-
-// This is the container for the user-defined counters.
-typedef std::map<std::string, Counter> UserCounters;
-
-
-// TimeUnit is passed to a benchmark in order to specify the order of magnitude
-// for the measured time.
-enum TimeUnit { kNanosecond, kMicrosecond, kMillisecond };
-
-// BigO is passed to a benchmark in order to specify the asymptotic
-// computational
-// complexity for the benchmark. In case oAuto is selected, complexity will be
-// calculated automatically to the best fit.
-enum BigO { oNone, o1, oN, oNSquared, oNCubed, oLogN, oNLogN, oAuto, oLambda };
-
-// BigOFunc is passed to a benchmark in order to specify the asymptotic
-// computational complexity for the benchmark.
-typedef double(BigOFunc)(int64_t);
-
-// StatisticsFunc is passed to a benchmark in order to compute some descriptive
-// statistics over all the measurements of some type
-typedef double(StatisticsFunc)(const std::vector<double>&);
-
-struct Statistics {
-  std::string name_;
-  StatisticsFunc* compute_;
-
-  Statistics(std::string name, StatisticsFunc* compute)
-    : name_(name), compute_(compute) {}
-};
-
-namespace internal {
-class ThreadTimer;
-class ThreadManager;
-
-enum ReportMode
-#if defined(BENCHMARK_HAS_CXX11)
-  : unsigned
-#else
-#endif
-  {
-  RM_Unspecified,  // The mode has not been manually specified
-  RM_Default,      // The mode is user-specified as default.
-  RM_ReportAggregatesOnly
-};
-}  // namespace internal
-
-// State is passed to a running Benchmark and contains state for the
-// benchmark to use.
-class State {
- public:
-  struct StateIterator;
-  friend struct StateIterator;
-
-  // Returns iterators used to run each iteration of a benchmark using a
-  // C++11 ranged-based for loop. These functions should not be called directly.
-  //
-  // REQUIRES: The benchmark has not started running yet. Neither begin nor end
-  // have been called previously.
-  //
-  // NOTE: KeepRunning may not be used after calling either of these functions.
-  BENCHMARK_ALWAYS_INLINE StateIterator begin();
-  BENCHMARK_ALWAYS_INLINE StateIterator end();
-
-  // Returns true if the benchmark should continue through another iteration.
-  // NOTE: A benchmark may not return from the test until KeepRunning() has
-  // returned false.
-  bool KeepRunning();
-
-  // Returns true iff the benchmark should run n more iterations.
-  // REQUIRES: 'n' > 0.
-  // NOTE: A benchmark must not return from the test until KeepRunningBatch()
-  // has returned false.
-  // NOTE: KeepRunningBatch() may overshoot by up to 'n' iterations.
-  //
-  // Intended usage:
-  //   while (state.KeepRunningBatch(1000)) {
-  //     // process 1000 elements
-  //   }
-  bool KeepRunningBatch(size_t n);
-
-  // REQUIRES: timer is running and 'SkipWithError(...)' has not been called
-  //           by the current thread.
-  // Stop the benchmark timer.  If not called, the timer will be
-  // automatically stopped after the last iteration of the benchmark loop.
-  //
-  // For threaded benchmarks the PauseTiming() function only pauses the timing
-  // for the current thread.
-  //
-  // NOTE: The "real time" measurement is per-thread. If different threads
-  // report different measurements the largest one is reported.
-  //
-  // NOTE: PauseTiming()/ResumeTiming() are relatively
-  // heavyweight, and so their use should generally be avoided
-  // within each benchmark iteration, if possible.
-  void PauseTiming();
-
-  // REQUIRES: timer is not running and 'SkipWithError(...)' has not been called
-  //           by the current thread.
-  // Start the benchmark timer.  The timer is NOT running on entrance to the
-  // benchmark function. It begins running after control flow enters the
-  // benchmark loop.
-  //
-  // NOTE: PauseTiming()/ResumeTiming() are relatively
-  // heavyweight, and so their use should generally be avoided
-  // within each benchmark iteration, if possible.
-  void ResumeTiming();
-
-  // REQUIRES: 'SkipWithError(...)' has not been called previously by the
-  //            current thread.
-  // Report the benchmark as resulting in an error with the specified 'msg'.
-  // After this call the user may explicitly 'return' from the benchmark.
-  //
-  // If the ranged-for style of benchmark loop is used, the user must explicitly
-  // break from the loop, otherwise all future iterations will be run.
-  // If the 'KeepRunning()' loop is used the current thread will automatically
-  // exit the loop at the end of the current iteration.
-  //
-  // For threaded benchmarks only the current thread stops executing and future
-  // calls to `KeepRunning()` will block until all threads have completed
-  // the `KeepRunning()` loop. If multiple threads report an error only the
-  // first error message is used.
-  //
-  // NOTE: Calling 'SkipWithError(...)' does not cause the benchmark to exit
-  // the current scope immediately. If the function is called from within
-  // the 'KeepRunning()' loop the current iteration will finish. It is the users
-  // responsibility to exit the scope as needed.
-  void SkipWithError(const char* msg);
-
-  // REQUIRES: called exactly once per iteration of the benchmarking loop.
-  // Set the manually measured time for this benchmark iteration, which
-  // is used instead of automatically measured time if UseManualTime() was
-  // specified.
-  //
-  // For threaded benchmarks the final value will be set to the largest
-  // reported values.
-  void SetIterationTime(double seconds);
-
-  // Set the number of bytes processed by the current benchmark
-  // execution.  This routine is typically called once at the end of a
-  // throughput oriented benchmark.  If this routine is called with a
-  // value > 0, the report is printed in MB/sec instead of nanoseconds
-  // per iteration.
-  //
-  // REQUIRES: a benchmark has exited its benchmarking loop.
-  BENCHMARK_ALWAYS_INLINE
-  void SetBytesProcessed(int64_t bytes) { bytes_processed_ = bytes; }
-
-  BENCHMARK_ALWAYS_INLINE
-  int64_t bytes_processed() const { return bytes_processed_; }
-
-  // If this routine is called with complexity_n > 0 and complexity report is
-  // requested for the
-  // family benchmark, then current benchmark will be part of the computation
-  // and complexity_n will
-  // represent the length of N.
-  BENCHMARK_ALWAYS_INLINE
-  void SetComplexityN(int64_t complexity_n) { complexity_n_ = complexity_n; }
-
-  BENCHMARK_ALWAYS_INLINE
-  int64_t complexity_length_n() { return complexity_n_; }
-
-  // If this routine is called with items > 0, then an items/s
-  // label is printed on the benchmark report line for the currently
-  // executing benchmark. It is typically called at the end of a processing
-  // benchmark where a processing items/second output is desired.
-  //
-  // REQUIRES: a benchmark has exited its benchmarking loop.
-  BENCHMARK_ALWAYS_INLINE
-  void SetItemsProcessed(int64_t items) { items_processed_ = items; }
-
-  BENCHMARK_ALWAYS_INLINE
-  int64_t items_processed() const { return items_processed_; }
-
-  // If this routine is called, the specified label is printed at the
-  // end of the benchmark report line for the currently executing
-  // benchmark.  Example:
-  //  static void BM_Compress(benchmark::State& state) {
-  //    ...
-  //    double compress = input_size / output_size;
-  //    state.SetLabel(StrFormat("compress:%.1f%%", 100.0*compression));
-  //  }
-  // Produces output that looks like:
-  //  BM_Compress   50         50   14115038  compress:27.3%
-  //
-  // REQUIRES: a benchmark has exited its benchmarking loop.
-  void SetLabel(const char* label);
-
-  void BENCHMARK_ALWAYS_INLINE SetLabel(const std::string& str) {
-    this->SetLabel(str.c_str());
-  }
-
-  // Range arguments for this run. CHECKs if the argument has been set.
-  BENCHMARK_ALWAYS_INLINE
-  int64_t range(std::size_t pos = 0) const {
-    assert(range_.size() > pos);
-    return range_[pos];
-  }
-
-  BENCHMARK_DEPRECATED_MSG("use 'range(0)' instead")
-  int64_t range_x() const { return range(0); }
-
-  BENCHMARK_DEPRECATED_MSG("use 'range(1)' instead")
-  int64_t range_y() const { return range(1); }
-
-  BENCHMARK_ALWAYS_INLINE
-  size_t iterations() const {
-    if (BENCHMARK_BUILTIN_EXPECT(!started_, false)) {
-      return 0;
-    }
-    return max_iterations - total_iterations_ + batch_leftover_;
-  }
-
-private: // items we expect on the first cache line (ie 64 bytes of the struct)
-
-  // When total_iterations_ is 0, KeepRunning() and friends will return false.
-  // May be larger than max_iterations.
-  size_t total_iterations_;
-
-  // When using KeepRunningBatch(), batch_leftover_ holds the number of
-  // iterations beyond max_iters that were run. Used to track
-  // completed_iterations_ accurately.
-  size_t batch_leftover_;
-
-public:
-  const size_t max_iterations;
-
-private:
-  bool started_;
-  bool finished_;
-  bool error_occurred_;
-
-private: // items we don't need on the first cache line
-  std::vector<int64_t> range_;
-
-  int64_t bytes_processed_;
-  int64_t items_processed_;
-
-  int64_t complexity_n_;
-
- public:
-  // Container for user-defined counters.
-  UserCounters counters;
-  // Index of the executing thread. Values from [0, threads).
-  const int thread_index;
-  // Number of threads concurrently executing the benchmark.
-  const int threads;
-
-
-  // TODO(EricWF) make me private
-  State(size_t max_iters, const std::vector<int64_t>& ranges, int thread_i,
-        int n_threads, internal::ThreadTimer* timer,
-        internal::ThreadManager* manager);
-
- private:
-  void StartKeepRunning();
-  // Implementation of KeepRunning() and KeepRunningBatch().
-  // is_batch must be true unless n is 1.
-  bool KeepRunningInternal(size_t n, bool is_batch);
-  void FinishKeepRunning();
-  internal::ThreadTimer* timer_;
-  internal::ThreadManager* manager_;
-  BENCHMARK_DISALLOW_COPY_AND_ASSIGN(State);
-};
-
-inline BENCHMARK_ALWAYS_INLINE
-bool State::KeepRunning() {
-  return KeepRunningInternal(1, /*is_batch=*/ false);
-}
-
-inline BENCHMARK_ALWAYS_INLINE
-bool State::KeepRunningBatch(size_t n) {
-  return KeepRunningInternal(n, /*is_batch=*/ true);
-}
-
-inline BENCHMARK_ALWAYS_INLINE
-bool State::KeepRunningInternal(size_t n, bool is_batch) {
-  // total_iterations_ is set to 0 by the constructor, and always set to a
-  // nonzero value by StartKepRunning().
-  assert(n > 0);
-  // n must be 1 unless is_batch is true.
-  assert(is_batch || n == 1);
-  if (BENCHMARK_BUILTIN_EXPECT(total_iterations_ >= n, true)) {
-    total_iterations_ -= n;
-    return true;
-  }
-  if (!started_) {
-    StartKeepRunning();
-    if (!error_occurred_ && total_iterations_ >= n) {
-      total_iterations_-= n;
-      return true;
-    }
-  }
-  // For non-batch runs, total_iterations_ must be 0 by now.
-  if (is_batch && total_iterations_ != 0) {
-    batch_leftover_  = n - total_iterations_;
-    total_iterations_ = 0;
-    return true;
-  }
-  FinishKeepRunning();
-  return false;
-}
-
-struct State::StateIterator {
-  struct BENCHMARK_UNUSED Value {};
-  typedef std::forward_iterator_tag iterator_category;
-  typedef Value value_type;
-  typedef Value reference;
-  typedef Value pointer;
-  typedef std::ptrdiff_t difference_type;
-
- private:
-  friend class State;
-  BENCHMARK_ALWAYS_INLINE
-  StateIterator() : cached_(0), parent_() {}
-
-  BENCHMARK_ALWAYS_INLINE
-  explicit StateIterator(State* st)
-      : cached_(st->error_occurred_ ? 0 : st->max_iterations), parent_(st) {}
-
- public:
-  BENCHMARK_ALWAYS_INLINE
-  Value operator*() const { return Value(); }
-
-  BENCHMARK_ALWAYS_INLINE
-  StateIterator& operator++() {
-    assert(cached_ > 0);
-    --cached_;
-    return *this;
-  }
-
-  BENCHMARK_ALWAYS_INLINE
-  bool operator!=(StateIterator const&) const {
-    if (BENCHMARK_BUILTIN_EXPECT(cached_ != 0, true)) return true;
-    parent_->FinishKeepRunning();
-    return false;
-  }
-
- private:
-  size_t cached_;
-  State* const parent_;
-};
-
-inline BENCHMARK_ALWAYS_INLINE State::StateIterator State::begin() {
-  return StateIterator(this);
-}
-inline BENCHMARK_ALWAYS_INLINE State::StateIterator State::end() {
-  StartKeepRunning();
-  return StateIterator();
-}
-
-namespace internal {
-
-typedef void(Function)(State&);
-
-// ------------------------------------------------------
-// Benchmark registration object.  The BENCHMARK() macro expands
-// into an internal::Benchmark* object.  Various methods can
-// be called on this object to change the properties of the benchmark.
-// Each method returns "this" so that multiple method calls can
-// chained into one expression.
-class Benchmark {
- public:
-  virtual ~Benchmark();
-
-  // Note: the following methods all return "this" so that multiple
-  // method calls can be chained together in one expression.
-
-  // Run this benchmark once with "x" as the extra argument passed
-  // to the function.
-  // REQUIRES: The function passed to the constructor must accept an arg1.
-  Benchmark* Arg(int64_t x);
-
-  // Run this benchmark with the given time unit for the generated output report
-  Benchmark* Unit(TimeUnit unit);
-
-  // Run this benchmark once for a number of values picked from the
-  // range [start..limit].  (start and limit are always picked.)
-  // REQUIRES: The function passed to the constructor must accept an arg1.
-  Benchmark* Range(int64_t start, int64_t limit);
-
-  // Run this benchmark once for all values in the range [start..limit] with
-  // specific step
-  // REQUIRES: The function passed to the constructor must accept an arg1.
-  Benchmark* DenseRange(int64_t start, int64_t limit, int step = 1);
-
-  // Run this benchmark once with "args" as the extra arguments passed
-  // to the function.
-  // REQUIRES: The function passed to the constructor must accept arg1, arg2 ...
-  Benchmark* Args(const std::vector<int64_t>& args);
-
-  // Equivalent to Args({x, y})
-  // NOTE: This is a legacy C++03 interface provided for compatibility only.
-  //   New code should use 'Args'.
-  Benchmark* ArgPair(int64_t x, int64_t y) {
-    std::vector<int64_t> args;
-    args.push_back(x);
-    args.push_back(y);
-    return Args(args);
-  }
-
-  // Run this benchmark once for a number of values picked from the
-  // ranges [start..limit].  (starts and limits are always picked.)
-  // REQUIRES: The function passed to the constructor must accept arg1, arg2 ...
-  Benchmark* Ranges(const std::vector<std::pair<int64_t, int64_t> >& ranges);
-
-  // Equivalent to ArgNames({name})
-  Benchmark* ArgName(const std::string& name);
-
-  // Set the argument names to display in the benchmark name. If not called,
-  // only argument values will be shown.
-  Benchmark* ArgNames(const std::vector<std::string>& names);
-
-  // Equivalent to Ranges({{lo1, hi1}, {lo2, hi2}}).
-  // NOTE: This is a legacy C++03 interface provided for compatibility only.
-  //   New code should use 'Ranges'.
-  Benchmark* RangePair(int64_t lo1, int64_t hi1, int64_t lo2, int64_t hi2) {
-    std::vector<std::pair<int64_t, int64_t> > ranges;
-    ranges.push_back(std::make_pair(lo1, hi1));
-    ranges.push_back(std::make_pair(lo2, hi2));
-    return Ranges(ranges);
-  }
-
-  // Pass this benchmark object to *func, which can customize
-  // the benchmark by calling various methods like Arg, Args,
-  // Threads, etc.
-  Benchmark* Apply(void (*func)(Benchmark* benchmark));
-
-  // Set the range multiplier for non-dense range. If not called, the range
-  // multiplier kRangeMultiplier will be used.
-  Benchmark* RangeMultiplier(int multiplier);
-
-  // Set the minimum amount of time to use when running this benchmark. This
-  // option overrides the `benchmark_min_time` flag.
-  // REQUIRES: `t > 0` and `Iterations` has not been called on this benchmark.
-  Benchmark* MinTime(double t);
-
-  // Specify the amount of iterations that should be run by this benchmark.
-  // REQUIRES: 'n > 0' and `MinTime` has not been called on this benchmark.
-  //
-  // NOTE: This function should only be used when *exact* iteration control is
-  //   needed and never to control or limit how long a benchmark runs, where
-  // `--benchmark_min_time=N` or `MinTime(...)` should be used instead.
-  Benchmark* Iterations(size_t n);
-
-  // Specify the amount of times to repeat this benchmark. This option overrides
-  // the `benchmark_repetitions` flag.
-  // REQUIRES: `n > 0`
-  Benchmark* Repetitions(int n);
-
-  // Specify if each repetition of the benchmark should be reported separately
-  // or if only the final statistics should be reported. If the benchmark
-  // is not repeated then the single result is always reported.
-  Benchmark* ReportAggregatesOnly(bool value = true);
-
-  // If a particular benchmark is I/O bound, runs multiple threads internally or
-  // if for some reason CPU timings are not representative, call this method. If
-  // called, the elapsed time will be used to control how many iterations are
-  // run, and in the printing of items/second or MB/seconds values.  If not
-  // called, the cpu time used by the benchmark will be used.
-  Benchmark* UseRealTime();
-
-  // If a benchmark must measure time manually (e.g. if GPU execution time is
-  // being
-  // measured), call this method. If called, each benchmark iteration should
-  // call
-  // SetIterationTime(seconds) to report the measured time, which will be used
-  // to control how many iterations are run, and in the printing of items/second
-  // or MB/second values.
-  Benchmark* UseManualTime();
-
-  // Set the asymptotic computational complexity for the benchmark. If called
-  // the asymptotic computational complexity will be shown on the output.
-  Benchmark* Complexity(BigO complexity = benchmark::oAuto);
-
-  // Set the asymptotic computational complexity for the benchmark. If called
-  // the asymptotic computational complexity will be shown on the output.
-  Benchmark* Complexity(BigOFunc* complexity);
-
-  // Add this statistics to be computed over all the values of benchmark run
-  Benchmark* ComputeStatistics(std::string name, StatisticsFunc* statistics);
-
-  // Support for running multiple copies of the same benchmark concurrently
-  // in multiple threads.  This may be useful when measuring the scaling
-  // of some piece of code.
-
-  // Run one instance of this benchmark concurrently in t threads.
-  Benchmark* Threads(int t);
-
-  // Pick a set of values T from [min_threads,max_threads].
-  // min_threads and max_threads are always included in T.  Run this
-  // benchmark once for each value in T.  The benchmark run for a
-  // particular value t consists of t threads running the benchmark
-  // function concurrently.  For example, consider:
-  //    BENCHMARK(Foo)->ThreadRange(1,16);
-  // This will run the following benchmarks:
-  //    Foo in 1 thread
-  //    Foo in 2 threads
-  //    Foo in 4 threads
-  //    Foo in 8 threads
-  //    Foo in 16 threads
-  Benchmark* ThreadRange(int min_threads, int max_threads);
-
-  // For each value n in the range, run this benchmark once using n threads.
-  // min_threads and max_threads are always included in the range.
-  // stride specifies the increment. E.g. DenseThreadRange(1, 8, 3) starts
-  // a benchmark with 1, 4, 7 and 8 threads.
-  Benchmark* DenseThreadRange(int min_threads, int max_threads, int stride = 1);
-
-  // Equivalent to ThreadRange(NumCPUs(), NumCPUs())
-  Benchmark* ThreadPerCpu();
-
-  virtual void Run(State& state) = 0;
-
-  // Used inside the benchmark implementation
-  struct Instance;
-
- protected:
-  explicit Benchmark(const char* name);
-  Benchmark(Benchmark const&);
-  void SetName(const char* name);
-
-  int ArgsCnt() const;
-
- private:
-  friend class BenchmarkFamilies;
-
-  std::string name_;
-  ReportMode report_mode_;
-  std::vector<std::string> arg_names_;   // Args for all benchmark runs
-  std::vector<std::vector<int64_t> > args_;  // Args for all benchmark runs
-  TimeUnit time_unit_;
-  int range_multiplier_;
-  double min_time_;
-  size_t iterations_;
-  int repetitions_;
-  bool use_real_time_;
-  bool use_manual_time_;
-  BigO complexity_;
-  BigOFunc* complexity_lambda_;
-  std::vector<Statistics> statistics_;
-  std::vector<int> thread_counts_;
-
-  Benchmark& operator=(Benchmark const&);
-};
-
-}  // namespace internal
-
-// Create and register a benchmark with the specified 'name' that invokes
-// the specified functor 'fn'.
-//
-// RETURNS: A pointer to the registered benchmark.
-internal::Benchmark* RegisterBenchmark(const char* name,
-                                       internal::Function* fn);
-
-#if defined(BENCHMARK_HAS_CXX11)
-template <class Lambda>
-internal::Benchmark* RegisterBenchmark(const char* name, Lambda&& fn);
-#endif
-
-// Remove all registered benchmarks. All pointers to previously registered
-// benchmarks are invalidated.
-void ClearRegisteredBenchmarks();
-
-namespace internal {
-// The class used to hold all Benchmarks created from static function.
-// (ie those created using the BENCHMARK(...) macros.
-class FunctionBenchmark : public Benchmark {
- public:
-  FunctionBenchmark(const char* name, Function* func)
-      : Benchmark(name), func_(func) {}
-
-  void Run(State& st) override;
-
- private:
-  Function* func_;
-};
-
-#ifdef BENCHMARK_HAS_CXX11
-template <class Lambda>
-class LambdaBenchmark : public Benchmark {
- public:
-  void Run(State& st) override { lambda_(st); }
-
- private:
-  template <class OLambda>
-  LambdaBenchmark(const char* name, OLambda&& lam)
-      : Benchmark(name), lambda_(std::forward<OLambda>(lam)) {}
-
-  LambdaBenchmark(LambdaBenchmark const&) = delete;
-
- private:
-  template <class Lam>
-  friend Benchmark* ::benchmark::RegisterBenchmark(const char*, Lam&&);
-
-  Lambda lambda_;
-};
-#endif
-
-}  // namespace internal
-
-inline internal::Benchmark* RegisterBenchmark(const char* name,
-                                              internal::Function* fn) {
-  return internal::RegisterBenchmarkInternal(
-      ::new internal::FunctionBenchmark(name, fn));
-}
-
-#ifdef BENCHMARK_HAS_CXX11
-template <class Lambda>
-internal::Benchmark* RegisterBenchmark(const char* name, Lambda&& fn) {
-  using BenchType = internal::LambdaBenchmark<typename std::decay<Lambda>::type>;
-  return internal::RegisterBenchmarkInternal(
-      ::new BenchType(name, std::forward<Lambda>(fn)));
-}
-#endif
-
-#if defined(BENCHMARK_HAS_CXX11) && \
-    (!defined(BENCHMARK_GCC_VERSION) || BENCHMARK_GCC_VERSION >= 409)
-template <class Lambda, class... Args>
-internal::Benchmark* RegisterBenchmark(const char* name, Lambda&& fn,
-                                       Args&&... args) {
-  return benchmark::RegisterBenchmark(
-      name, [=](benchmark::State& st) { fn(st, args...); });
-}
-#else
-#define BENCHMARK_HAS_NO_VARIADIC_REGISTER_BENCHMARK
-#endif
-
-// The base class for all fixture tests.
-class Fixture : public internal::Benchmark {
- public:
-  Fixture() : internal::Benchmark("") {}
-
-  void Run(State& st) override {
-    this->SetUp(st);
-    this->BenchmarkCase(st);
-    this->TearDown(st);
-  }
-
-  // These will be deprecated ...
-  virtual void SetUp(const State&) {}
-  virtual void TearDown(const State&) {}
-  // ... In favor of these.
-  virtual void SetUp(State& st) { SetUp(const_cast<const State&>(st)); }
-  virtual void TearDown(State& st) { TearDown(const_cast<const State&>(st)); }
-
- protected:
-  virtual void BenchmarkCase(State&) = 0;
-};
-
-}  // namespace benchmark
-
-// ------------------------------------------------------
-// Macro to register benchmarks
-
-// Check that __COUNTER__ is defined and that __COUNTER__ increases by 1
-// every time it is expanded. X + 1 == X + 0 is used in case X is defined to be
-// empty. If X is empty the expression becomes (+1 == +0).
-#if defined(__COUNTER__) && (__COUNTER__ + 1 == __COUNTER__ + 0)
-#define BENCHMARK_PRIVATE_UNIQUE_ID __COUNTER__
-#else
-#define BENCHMARK_PRIVATE_UNIQUE_ID __LINE__
-#endif
-
-// Helpers for generating unique variable names
-#define BENCHMARK_PRIVATE_NAME(n) \
-  BENCHMARK_PRIVATE_CONCAT(_benchmark_, BENCHMARK_PRIVATE_UNIQUE_ID, n)
-#define BENCHMARK_PRIVATE_CONCAT(a, b, c) BENCHMARK_PRIVATE_CONCAT2(a, b, c)
-#define BENCHMARK_PRIVATE_CONCAT2(a, b, c) a##b##c
-
-#define BENCHMARK_PRIVATE_DECLARE(n)                                 \
-  static ::benchmark::internal::Benchmark* BENCHMARK_PRIVATE_NAME(n) \
-      BENCHMARK_UNUSED
-
-#define BENCHMARK(n)                                     \
-  BENCHMARK_PRIVATE_DECLARE(n) =                         \
-      (::benchmark::internal::RegisterBenchmarkInternal( \
-          new ::benchmark::internal::FunctionBenchmark(#n, n)))
-
-// Old-style macros
-#define BENCHMARK_WITH_ARG(n, a) BENCHMARK(n)->Arg((a))
-#define BENCHMARK_WITH_ARG2(n, a1, a2) BENCHMARK(n)->Args({(a1), (a2)})
-#define BENCHMARK_WITH_UNIT(n, t) BENCHMARK(n)->Unit((t))
-#define BENCHMARK_RANGE(n, lo, hi) BENCHMARK(n)->Range((lo), (hi))
-#define BENCHMARK_RANGE2(n, l1, h1, l2, h2) \
-  BENCHMARK(n)->RangePair({{(l1), (h1)}, {(l2), (h2)}})
-
-#ifdef BENCHMARK_HAS_CXX11
-
-// Register a benchmark which invokes the function specified by `func`
-// with the additional arguments specified by `...`.
-//
-// For example:
-//
-// template <class ...ExtraArgs>`
-// void BM_takes_args(benchmark::State& state, ExtraArgs&&... extra_args) {
-//  [...]
-//}
-// /* Registers a benchmark named "BM_takes_args/int_string_test` */
-// BENCHMARK_CAPTURE(BM_takes_args, int_string_test, 42, std::string("abc"));
-#define BENCHMARK_CAPTURE(func, test_case_name, ...)     \
-  BENCHMARK_PRIVATE_DECLARE(func) =                      \
-      (::benchmark::internal::RegisterBenchmarkInternal( \
-          new ::benchmark::internal::FunctionBenchmark(  \
-              #func "/" #test_case_name,                 \
-              [](::benchmark::State& st) { func(st, __VA_ARGS__); })))
-
-#endif  // BENCHMARK_HAS_CXX11
-
-// This will register a benchmark for a templatized function.  For example:
-//
-// template<int arg>
-// void BM_Foo(int iters);
-//
-// BENCHMARK_TEMPLATE(BM_Foo, 1);
-//
-// will register BM_Foo<1> as a benchmark.
-#define BENCHMARK_TEMPLATE1(n, a)                        \
-  BENCHMARK_PRIVATE_DECLARE(n) =                         \
-      (::benchmark::internal::RegisterBenchmarkInternal( \
-          new ::benchmark::internal::FunctionBenchmark(#n "<" #a ">", n<a>)))
-
-#define BENCHMARK_TEMPLATE2(n, a, b)                                         \
-  BENCHMARK_PRIVATE_DECLARE(n) =                                             \
-      (::benchmark::internal::RegisterBenchmarkInternal(                     \
-          new ::benchmark::internal::FunctionBenchmark(#n "<" #a "," #b ">", \
-                                                       n<a, b>)))
-
-#ifdef BENCHMARK_HAS_CXX11
-#define BENCHMARK_TEMPLATE(n, ...)                       \
-  BENCHMARK_PRIVATE_DECLARE(n) =                         \
-      (::benchmark::internal::RegisterBenchmarkInternal( \
-          new ::benchmark::internal::FunctionBenchmark(  \
-              #n "<" #__VA_ARGS__ ">", n<__VA_ARGS__>)))
-#else
-#define BENCHMARK_TEMPLATE(n, a) BENCHMARK_TEMPLATE1(n, a)
-#endif
-
-#define BENCHMARK_PRIVATE_DECLARE_F(BaseClass, Method)        \
-  class BaseClass##_##Method##_Benchmark : public BaseClass { \
-   public:                                                    \
-    BaseClass##_##Method##_Benchmark() : BaseClass() {        \
-      this->SetName(#BaseClass "/" #Method);                  \
-    }                                                         \
-                                                              \
-   protected:                                                 \
-    virtual void BenchmarkCase(::benchmark::State&);          \
-  };
-
-#define BENCHMARK_TEMPLATE1_PRIVATE_DECLARE_F(BaseClass, Method, a) \
-  class BaseClass##_##Method##_Benchmark : public BaseClass<a> {    \
-   public:                                                          \
-    BaseClass##_##Method##_Benchmark() : BaseClass<a>() {           \
-      this->SetName(#BaseClass"<" #a ">/" #Method);                 \
-    }                                                               \
-                                                                    \
-   protected:                                                       \
-    virtual void BenchmarkCase(::benchmark::State&);                \
-  };
-
-#define BENCHMARK_TEMPLATE2_PRIVATE_DECLARE_F(BaseClass, Method, a, b) \
-  class BaseClass##_##Method##_Benchmark : public BaseClass<a, b> {    \
-   public:                                                             \
-    BaseClass##_##Method##_Benchmark() : BaseClass<a, b>() {           \
-      this->SetName(#BaseClass"<" #a "," #b ">/" #Method);             \
-    }                                                                  \
-                                                                       \
-   protected:                                                          \
-    virtual void BenchmarkCase(::benchmark::State&);                   \
-  };
-
-#ifdef BENCHMARK_HAS_CXX11
-#define BENCHMARK_TEMPLATE_PRIVATE_DECLARE_F(BaseClass, Method, ...)       \
-  class BaseClass##_##Method##_Benchmark : public BaseClass<__VA_ARGS__> { \
-   public:                                                                 \
-    BaseClass##_##Method##_Benchmark() : BaseClass<__VA_ARGS__>() {        \
-      this->SetName(#BaseClass"<" #__VA_ARGS__ ">/" #Method);              \
-    }                                                                      \
-                                                                           \
-   protected:                                                              \
-    virtual void BenchmarkCase(::benchmark::State&);                       \
-  };
-#else
-#define BENCHMARK_TEMPLATE_PRIVATE_DECLARE_F(n, a) BENCHMARK_TEMPLATE1_PRIVATE_DECLARE_F(n, a)
-#endif
-
-#define BENCHMARK_DEFINE_F(BaseClass, Method)    \
-  BENCHMARK_PRIVATE_DECLARE_F(BaseClass, Method) \
-  void BaseClass##_##Method##_Benchmark::BenchmarkCase
-
-#define BENCHMARK_TEMPLATE1_DEFINE_F(BaseClass, Method, a)    \
-  BENCHMARK_TEMPLATE1_PRIVATE_DECLARE_F(BaseClass, Method, a) \
-  void BaseClass##_##Method##_Benchmark::BenchmarkCase
-
-#define BENCHMARK_TEMPLATE2_DEFINE_F(BaseClass, Method, a, b)    \
-  BENCHMARK_TEMPLATE2_PRIVATE_DECLARE_F(BaseClass, Method, a, b) \
-  void BaseClass##_##Method##_Benchmark::BenchmarkCase
-
-#ifdef BENCHMARK_HAS_CXX11
-#define BENCHMARK_TEMPLATE_DEFINE_F(BaseClass, Method, ...)            \
-  BENCHMARK_TEMPLATE_PRIVATE_DECLARE_F(BaseClass, Method, __VA_ARGS__) \
-  void BaseClass##_##Method##_Benchmark::BenchmarkCase
-#else
-#define BENCHMARK_TEMPLATE_DEFINE_F(BaseClass, Method, a) BENCHMARK_TEMPLATE1_DEFINE_F(BaseClass, Method, a)
-#endif
-
-#define BENCHMARK_REGISTER_F(BaseClass, Method) \
-  BENCHMARK_PRIVATE_REGISTER_F(BaseClass##_##Method##_Benchmark)
-
-#define BENCHMARK_PRIVATE_REGISTER_F(TestName) \
-  BENCHMARK_PRIVATE_DECLARE(TestName) =        \
-      (::benchmark::internal::RegisterBenchmarkInternal(new TestName()))
-
-// This macro will define and register a benchmark within a fixture class.
-#define BENCHMARK_F(BaseClass, Method)           \
-  BENCHMARK_PRIVATE_DECLARE_F(BaseClass, Method) \
-  BENCHMARK_REGISTER_F(BaseClass, Method);       \
-  void BaseClass##_##Method##_Benchmark::BenchmarkCase
-
-#define BENCHMARK_TEMPLATE1_F(BaseClass, Method, a)           \
-  BENCHMARK_TEMPLATE1_PRIVATE_DECLARE_F(BaseClass, Method, a) \
-  BENCHMARK_REGISTER_F(BaseClass, Method);                    \
-  void BaseClass##_##Method##_Benchmark::BenchmarkCase
-
-#define BENCHMARK_TEMPLATE2_F(BaseClass, Method, a, b)           \
-  BENCHMARK_TEMPLATE2_PRIVATE_DECLARE_F(BaseClass, Method, a, b) \
-  BENCHMARK_REGISTER_F(BaseClass, Method);                       \
-  void BaseClass##_##Method##_Benchmark::BenchmarkCase
-
-#ifdef BENCHMARK_HAS_CXX11
-#define BENCHMARK_TEMPLATE_F(BaseClass, Method, ...)           \
-  BENCHMARK_TEMPLATE_PRIVATE_DECLARE_F(BaseClass, Method, __VA_ARGS__) \
-  BENCHMARK_REGISTER_F(BaseClass, Method);                     \
-  void BaseClass##_##Method##_Benchmark::BenchmarkCase
-#else
-#define BENCHMARK_TEMPLATE_F(BaseClass, Method, a) BENCHMARK_TEMPLATE1_F(BaseClass, Method, a)
-#endif
-
-// Helper macro to create a main routine in a test that runs the benchmarks
-#define BENCHMARK_MAIN()                   \
-  int main(int argc, char** argv) {        \
-    ::benchmark::Initialize(&argc, argv);  \
-    if (::benchmark::ReportUnrecognizedArguments(argc, argv)) return 1; \
-    ::benchmark::RunSpecifiedBenchmarks(); \
-  }                                        \
-  int main(int, char**)
-
-
-// ------------------------------------------------------
-// Benchmark Reporters
-
-namespace benchmark {
-
-struct CPUInfo {
-  struct CacheInfo {
-    std::string type;
-    int level;
-    int size;
-    int num_sharing;
-  };
-
-  int num_cpus;
-  double cycles_per_second;
-  std::vector<CacheInfo> caches;
-  bool scaling_enabled;
-
-  static const CPUInfo& Get();
-
- private:
-  CPUInfo();
-  BENCHMARK_DISALLOW_COPY_AND_ASSIGN(CPUInfo);
-};
-
-// Interface for custom benchmark result printers.
-// By default, benchmark reports are printed to stdout. However an application
-// can control the destination of the reports by calling
-// RunSpecifiedBenchmarks and passing it a custom reporter object.
-// The reporter object must implement the following interface.
-class BenchmarkReporter {
- public:
-  struct Context {
-    CPUInfo const& cpu_info;
-    // The number of chars in the longest benchmark name.
-    size_t name_field_width;
-    static const char *executable_name;
-    Context();
-  };
-
-  struct Run {
-    Run()
-        : error_occurred(false),
-          iterations(1),
-          time_unit(kNanosecond),
-          real_accumulated_time(0),
-          cpu_accumulated_time(0),
-          bytes_per_second(0),
-          items_per_second(0),
-          max_heapbytes_used(0),
-          complexity(oNone),
-          complexity_lambda(),
-          complexity_n(0),
-          report_big_o(false),
-          report_rms(false),
-          counters() {}
-
-    std::string benchmark_name;
-    std::string report_label;  // Empty if not set by benchmark.
-    bool error_occurred;
-    std::string error_message;
-
-    int64_t iterations;
-    TimeUnit time_unit;
-    double real_accumulated_time;
-    double cpu_accumulated_time;
-
-    // Return a value representing the real time per iteration in the unit
-    // specified by 'time_unit'.
-    // NOTE: If 'iterations' is zero the returned value represents the
-    // accumulated time.
-    double GetAdjustedRealTime() const;
-
-    // Return a value representing the cpu time per iteration in the unit
-    // specified by 'time_unit'.
-    // NOTE: If 'iterations' is zero the returned value represents the
-    // accumulated time.
-    double GetAdjustedCPUTime() const;
-
-    // Zero if not set by benchmark.
-    double bytes_per_second;
-    double items_per_second;
-
-    // This is set to 0.0 if memory tracing is not enabled.
-    double max_heapbytes_used;
-
-    // Keep track of arguments to compute asymptotic complexity
-    BigO complexity;
-    BigOFunc* complexity_lambda;
-    int64_t complexity_n;
-
-    // what statistics to compute from the measurements
-    const std::vector<Statistics>* statistics;
-
-    // Inform print function whether the current run is a complexity report
-    bool report_big_o;
-    bool report_rms;
-
-    UserCounters counters;
-  };
-
-  // Construct a BenchmarkReporter with the output stream set to 'std::cout'
-  // and the error stream set to 'std::cerr'
-  BenchmarkReporter();
-
-  // Called once for every suite of benchmarks run.
-  // The parameter "context" contains information that the
-  // reporter may wish to use when generating its report, for example the
-  // platform under which the benchmarks are running. The benchmark run is
-  // never started if this function returns false, allowing the reporter
-  // to skip runs based on the context information.
-  virtual bool ReportContext(const Context& context) = 0;
-
-  // Called once for each group of benchmark runs, gives information about
-  // cpu-time and heap memory usage during the benchmark run. If the group
-  // of runs contained more than two entries then 'report' contains additional
-  // elements representing the mean and standard deviation of those runs.
-  // Additionally if this group of runs was the last in a family of benchmarks
-  // 'reports' contains additional entries representing the asymptotic
-  // complexity and RMS of that benchmark family.
-  virtual void ReportRuns(const std::vector<Run>& report) = 0;
-
-  // Called once and only once after ever group of benchmarks is run and
-  // reported.
-  virtual void Finalize() {}
-
-  // REQUIRES: The object referenced by 'out' is valid for the lifetime
-  // of the reporter.
-  void SetOutputStream(std::ostream* out) {
-    assert(out);
-    output_stream_ = out;
-  }
-
-  // REQUIRES: The object referenced by 'err' is valid for the lifetime
-  // of the reporter.
-  void SetErrorStream(std::ostream* err) {
-    assert(err);
-    error_stream_ = err;
-  }
-
-  std::ostream& GetOutputStream() const { return *output_stream_; }
-
-  std::ostream& GetErrorStream() const { return *error_stream_; }
-
-  virtual ~BenchmarkReporter();
-
-  // Write a human readable string to 'out' representing the specified
-  // 'context'.
-  // REQUIRES: 'out' is non-null.
-  static void PrintBasicContext(std::ostream* out, Context const& context);
-
- private:
-  std::ostream* output_stream_;
-  std::ostream* error_stream_;
-};
-
-// Simple reporter that outputs benchmark data to the console. This is the
-// default reporter used by RunSpecifiedBenchmarks().
-class ConsoleReporter : public BenchmarkReporter {
-public:
-  enum OutputOptions {
-    OO_None = 0,
-    OO_Color = 1,
-    OO_Tabular = 2,
-    OO_ColorTabular = OO_Color|OO_Tabular,
-    OO_Defaults = OO_ColorTabular
-  };
-  explicit ConsoleReporter(OutputOptions opts_ = OO_Defaults)
-      : output_options_(opts_), name_field_width_(0),
-        prev_counters_(), printed_header_(false) {}
-
-  bool ReportContext(const Context& context) override;
-  void ReportRuns(const std::vector<Run>& reports) override;
-
- protected:
-  virtual void PrintRunData(const Run& report);
-  virtual void PrintHeader(const Run& report);
-
-  OutputOptions output_options_;
-  size_t name_field_width_;
-  UserCounters prev_counters_;
-  bool printed_header_;
-};
-
-class JSONReporter : public BenchmarkReporter {
- public:
-  JSONReporter() : first_report_(true) {}
-  bool ReportContext(const Context& context) override;
-  void ReportRuns(const std::vector<Run>& reports) override;
-  void Finalize() override;
-
- private:
-  void PrintRunData(const Run& report);
-
-  bool first_report_;
-};
-
-class CSVReporter : public BenchmarkReporter {
- public:
-  CSVReporter() : printed_header_(false) {}
-  bool ReportContext(const Context& context) override;
-  void ReportRuns(const std::vector<Run>& reports) override;
-
- private:
-  void PrintRunData(const Run& report);
-
-  bool printed_header_;
-  std::set< std::string > user_counter_names_;
-};
-
-inline const char* GetTimeUnitString(TimeUnit unit) {
-  switch (unit) {
-    case kMillisecond:
-      return "ms";
-    case kMicrosecond:
-      return "us";
-    case kNanosecond:
-      return "ns";
-  }
-  BENCHMARK_UNREACHABLE();
-}
-
-inline double GetTimeUnitMultiplier(TimeUnit unit) {
-  switch (unit) {
-    case kMillisecond:
-      return 1e3;
-    case kMicrosecond:
-      return 1e6;
-    case kNanosecond:
-      return 1e9;
-  }
-  BENCHMARK_UNREACHABLE();
-}
-
-} // namespace benchmark
-
-#endif  // BENCHMARK_BENCHMARK_H_