Change --code-comments default to true. Code comments activated only if disassembly is activated.

runtime/vm/flow_graph_compiler.cc

 // Copyright (c) 2013, 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/globals.h"  // Needed here to get TARGET_ARCH_XXX.
 
 #include "vm/flow_graph_compiler.h"
 
 #include "vm/cha.h"
 #include "vm/dart_entry.h"
 #include "vm/debugger.h"
 #include "vm/deopt_instructions.h"
 #include "vm/flow_graph_allocator.h"
 #include "vm/il_printer.h"
 #include "vm/intrinsifier.h"
 #include "vm/locations.h"
 #include "vm/longjump.h"
 #include "vm/object_store.h"
 #include "vm/parser.h"
 #include "vm/stack_frame.h"
 #include "vm/stub_code.h"
 #include "vm/symbols.h"
 
 namespace dart {
 
 DECLARE_FLAG(bool, code_comments);
+DECLARE_FLAG(bool, disassemble);
+DECLARE_FLAG(bool, disassemble_optimized);
 DECLARE_FLAG(bool, enable_type_checks);
 DECLARE_FLAG(bool, intrinsify);
 DECLARE_FLAG(bool, propagate_ic_data);
 DECLARE_FLAG(bool, report_usage_count);
 DECLARE_FLAG(int, optimization_counter_threshold);
 DECLARE_FLAG(bool, use_cha);
 DECLARE_FLAG(bool, use_osr);
 DEFINE_FLAG(bool, enable_simd_inline, true,
     "Enable inlining of SIMD related method calls.");
 
@@ skipping 220 matching lines @@
     set_current_block(entry);
 
     if (WasCompacted(entry)) {
       continue;
     }
 
     entry->EmitNativeCode(this);
     // Compile all successors until an exit, branch, or a block entry.
     for (ForwardInstructionIterator it(entry); !it.Done(); it.Advance()) {
       Instruction* instr = it.Current();
-      if (FLAG_code_comments) EmitComment(instr);
+      if (FLAG_code_comments &&
+          (FLAG_disassemble || FLAG_disassemble_optimized)) {
+        EmitComment(instr);
+      }
       if (instr->IsParallelMove()) {
         parallel_move_resolver_.EmitNativeCode(instr->AsParallelMove());
       } else {
         EmitInstructionPrologue(instr);
         ASSERT(pending_deoptimization_env_ == NULL);
         pending_deoptimization_env_ = instr->env();
         instr->EmitNativeCode(this);
         pending_deoptimization_env_ = NULL;
         EmitInstructionEpilogue(instr);
       }
@@ skipping 975 matching lines @@
 
   for (int i = 0; i < len; i++) {
     sorted->Add(CidTarget(ic_data.GetReceiverClassIdAt(i),
                           &Function::ZoneHandle(ic_data.GetTargetAt(i)),
                           ic_data.GetCountAt(i)));
   }
   sorted->Sort(HighestCountFirst);
 }
 
 }  // namespace dart