Add histogram timers for (de-)serialization during compilation.

R=yangguo@chromium.org
BUG=

Review URL: https://codereview.chromium.org/578263004

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24127 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/compiler.cc

@@ -1170,6 +1170,7 @@ Handle<SharedFunctionInfo> Compiler::CompileScript(
     if (FLAG_serialize_toplevel &&
         compile_options == ScriptCompiler::kConsumeCodeCache &&
         !isolate->debug()->is_loaded()) {
+      HistogramTimerScope timer(isolate->counters()->compile_deserialize());
       return CodeSerializer::Deserialize(isolate, *cached_data, source);
     } else {
       maybe_result = compilation_cache->LookupScript(
@@ -1216,6 +1217,8 @@ Handle<SharedFunctionInfo> Compiler::CompileScript(
       compilation_cache->PutScript(source, context, result);
       if (FLAG_serialize_toplevel &&
           compile_options == ScriptCompiler::kProduceCodeCache) {
+        HistogramTimerScope histogram_timer(
+            isolate->counters()->compile_serialize());
         *cached_data = CodeSerializer::Serialize(isolate, result, source);
         if (FLAG_profile_deserialization) {
           PrintF("[Compiling and serializing %d bytes took %0.3f ms]\n",

src/counters.h

@@ -311,7 +311,11 @@ class HistogramTimerScope BASE_EMBEDDED {
   HT(pre_parse, V8.PreParse)                                 \
   /* Total compilation times. */                             \
   HT(compile, V8.Compile)                                    \
-  HT(compile_eval, V8.CompileEval)
+  HT(compile_eval, V8.CompileEval)                           \
+  /* Serialization as part of compilation (code caching) */  \
+  HT(compile_serialize, V8.CompileSerialize)                 \
+  HT(compile_deserialize, V8.CompileDeserialize)
+
 
 #define HISTOGRAM_PERCENTAGE_LIST(HP)                                 \
   /* Heap fragmentation. */                                           \