StatSummarizer: Make it work without needing the GraphDef.

This will allow the StatSummarizer to be instantiated and used
even when the GraphDef is not easily accessible. A consequence of
this is that the BY_DEFINITION_ORDER ordering of stats is no
longer available, but that was deemed acceptable for this change.

Other notables:
- Added a basic C++ unittest for stat_summarizer.
- Added some commentary about caveats about summaries over runs
  that involve GPUs or partitioned graphs. These caveats existed
  in the prior implementation as well.
Change: 146076563

1 files changed, 1 insertions, 2 deletions

diff --git a/tensorflow/tools/benchmark/benchmark_model.cc b/tensorflow/tools/benchmark/benchmark_model.cc
index 86416db953..180600e3b4 100644
--- a/tensorflow/tools/benchmark/benchmark_model.cc
+++ b/tensorflow/tools/benchmark/benchmark_model.cc
@@ -370,8 +370,7 @@ int Main(int argc, char** argv) {
   stats_options.memory_limit = memory_limit;
   stats_options.show_type = show_type;
   stats_options.show_summary = show_summary;
-  stats.reset(
-      new tensorflow::StatSummarizer(*(graph_def.get()), stats_options));
+  stats.reset(new tensorflow::StatSummarizer(stats_options));
 
   const double sleep_seconds = std::strtod(run_delay.c_str(), nullptr);