Make compilation VM tags more fine grained

runtime/vm/compiler.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/compiler.h"
 
 #include "vm/assembler.h"
 
 #include "vm/ast_printer.h"
 #include "vm/block_scheduler.h"
@@ skipping 246 matching lines @@
 static bool CompileParsedFunctionHelper(ParsedFunction* parsed_function,
                                         bool optimized,
                                         intptr_t osr_id) {
   const Function& function = parsed_function->function();
   if (optimized && !function.IsOptimizable()) {
     return false;
   }
   TimerScope timer(FLAG_compiler_stats, &CompilerStats::codegen_timer);
   bool is_compiled = false;
   Isolate* isolate = Isolate::Current();
-  VMTagScope tagScope(isolate, VMTag::kCompileTagId);
+  const intptr_t compiler_tag = optimized ? VMTag::kCompileOptimizedTagId :
+                                            VMTag::kCompileUnoptimizedTagId;
+  VMTagScope tagScope(isolate, compiler_tag);
   HANDLESCOPE(isolate);
   isolate->set_cha_used(false);
 
   // We may reattempt compilation if the function needs to be assembled using
   // far branches on ARM and MIPS. In the else branch of the setjmp call,
   // done is set to false, and use_far_branches is set to true if there is a
   // longjmp from the ARM or MIPS assemblers. In all other paths through this
   // while loop, done is set to true. use_far_branches is always false on ia32
   // and x64.
   bool done = false;
@@ skipping 708 matching lines @@
     const Object& result =
       Object::Handle(isolate->object_store()->sticky_error());
     isolate->object_store()->clear_sticky_error();
     return result.raw();
   }
   UNREACHABLE();
   return Object::null();
 }
 
 }  // namespace dart