Add --trace-parse flag to parser.

src/parser.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 549 matching lines @@
     scanner().SetHarmonyScoping(true);
   }
   if ((parser_flags & kAllowModules) != 0) {
     scanner().SetHarmonyModules(true);
   }
 }
 
 
 FunctionLiteral* Parser::ParseProgram() {
   ZoneScope zone_scope(zone(), DONT_DELETE_ON_EXIT);
-
   HistogramTimerScope timer(isolate()->counters()->parse());
   Handle<String> source(String::cast(script_->source()));
   isolate()->counters()->total_parse_size()->Increment(source->length());
+  int64_t start = FLAG_trace_parse ? OS::Ticks() : 0;
   fni_ = new(zone()) FuncNameInferrer(isolate(), zone());
 
   // Initialize parser state.
   source->TryFlatten();
+  FunctionLiteral* result;
   if (source->IsExternalTwoByteString()) {
     // Notice that the stream is destroyed at the end of the branch block.
     // The last line of the blocks can't be moved outside, even though they're
     // identical calls.
     ExternalTwoByteStringUtf16CharacterStream stream(
         Handle<ExternalTwoByteString>::cast(source), 0, source->length());
     scanner_.Initialize(&stream);
-    return DoParseProgram(info(), source, &zone_scope);
+    result = DoParseProgram(info(), source, &zone_scope);
   } else {
     GenericStringUtf16CharacterStream stream(source, 0, source->length());
     scanner_.Initialize(&stream);
-    return DoParseProgram(info(), source, &zone_scope);
+    result = DoParseProgram(info(), source, &zone_scope);
   }
+
+  if (FLAG_trace_parse && result != NULL) {
+    double ms = static_cast<double>(OS::Ticks() - start) / 1000;
+    if (info()->is_eval()) {
+      PrintF("[parsing eval");
+    } else if (info()->script()->name()->IsString()) {
+      String* name = String::cast(info()->script()->name());
+      SmartArrayPointer<char> name_chars = name->ToCString();
+      PrintF("[parsing script: %s", *name_chars);
+    } else {
+      PrintF("[parsing script");
+    }
+    PrintF(" - took %0.3f ms]\n", ms);
+  }
+  return result;
 }
 
 
 FunctionLiteral* Parser::DoParseProgram(CompilationInfo* info,
                                         Handle<String> source,
                                         ZoneScope* zone_scope) {
   ASSERT(top_scope_ == NULL);
   ASSERT(target_stack_ == NULL);
   if (pre_data_ != NULL) pre_data_->Initialize();
 
@@ skipping 60 matching lines @@
   if (result == NULL) zone_scope->DeleteOnExit();
   return result;
 }
 
 
 FunctionLiteral* Parser::ParseLazy() {
   ZoneScope zone_scope(zone(), DONT_DELETE_ON_EXIT);
   HistogramTimerScope timer(isolate()->counters()->parse_lazy());
   Handle<String> source(String::cast(script_->source()));
   isolate()->counters()->total_parse_size()->Increment(source->length());
+  int64_t start = FLAG_trace_parse ? OS::Ticks() : 0;
+  Handle<SharedFunctionInfo> shared_info = info()->shared_info();
 
-  Handle<SharedFunctionInfo> shared_info = info()->shared_info();
   // Initialize parser state.
   source->TryFlatten();
+  FunctionLiteral* result;
   if (source->IsExternalTwoByteString()) {
     ExternalTwoByteStringUtf16CharacterStream stream(
         Handle<ExternalTwoByteString>::cast(source),
         shared_info->start_position(),
         shared_info->end_position());
-    FunctionLiteral* result = ParseLazy(&stream, &zone_scope);
-    return result;
+    result = ParseLazy(&stream, &zone_scope);
   } else {
     GenericStringUtf16CharacterStream stream(source,
                                              shared_info->start_position(),
                                              shared_info->end_position());
-    FunctionLiteral* result = ParseLazy(&stream, &zone_scope);
-    return result;
+    result = ParseLazy(&stream, &zone_scope);
   }
+
+  if (FLAG_trace_parse && result != NULL) {
+    double ms = static_cast<double>(OS::Ticks() - start) / 1000;
+    SmartArrayPointer<char> name_chars = result->name()->ToCString();
+    PrintF("[parsing function: %s - took %0.3f ms]\n", *name_chars, ms);
+  }
+  return result;
 }
 
 
 FunctionLiteral* Parser::ParseLazy(Utf16CharacterStream* source,
                                    ZoneScope* zone_scope) {
   Handle<SharedFunctionInfo> shared_info = info()->shared_info();
   scanner_.Initialize(source);
   ASSERT(top_scope_ == NULL);
   ASSERT(target_stack_ == NULL);
 
@@ skipping 5354 matching lines @@
       ASSERT(info->isolate()->has_pending_exception());
     } else {
       result = parser.ParseProgram();
     }
   }
   info->SetFunction(result);
   return (result != NULL);
 }
 
 } }  // namespace v8::internal