PATCH (not to be comitted): Support for printing instruction statistics

runtime/vm/clustered_snapshot.cc

Index: runtime/vm/clustered_snapshot.cc
diff --git a/runtime/vm/clustered_snapshot.cc b/runtime/vm/clustered_snapshot.cc
index e561a54f2f0b0c315fcdc13f63afbd8f7e98f704..762aebd232a4e36782e123d23aa7e366fc9443ac 100644
--- a/runtime/vm/clustered_snapshot.cc
+++ b/runtime/vm/clustered_snapshot.cc
@@ -23,6 +23,9 @@
 
 namespace dart {
 
+DEFINE_FLAG(bool, print_instruction_stats, false,
+            "Print instruction statistics");
+
 static RawObject* AllocateUninitialized(PageSpace* old_space, intptr_t size) {
   ASSERT(Utils::IsAligned(size, kObjectAlignment));
   uword address =
@@ -5332,6 +5335,10 @@ void FullSnapshotWriter::WriteFullSnapshot() {
   if (FLAG_print_snapshot_sizes) {
     OS::Print("Total(CodeSize): %" Pd "\n", total_size);
   }
+
+  if (FLAG_print_instruction_stats) {
+    instructions_writer_->DumpCombinedCodeStatistics();
+  }
 }