[turbofan] fix block mapping in code comments

src/compiler/code-generator.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/compiler/code-generator.h"
 
 #include "src/compiler/code-generator-impl.h"
 #include "src/compiler/linkage.h"
 #include "src/compiler/pipeline.h"
 
@@ skipping 89 matching lines @@
 
 
 void CodeGenerator::AssembleInstruction(Instruction* instr) {
   if (instr->IsBlockStart()) {
     // Bind a label for a block start and handle parallel moves.
     BlockStartInstruction* block_start = BlockStartInstruction::cast(instr);
     current_block_ = block_start->rpo_number();
     if (FLAG_code_comments) {
       // TODO(titzer): these code comments are a giant memory leak.
       Vector<char> buffer = Vector<char>::New(32);
-      // TODO(dcarney): should not be rpo number there
-      SNPrintF(buffer, "-- B%d (rpo) start --", current_block_.ToInt());
+      SNPrintF(buffer, "-- B%d start --", block_start->id().ToInt());
       masm()->RecordComment(buffer.start());
     }
     masm()->bind(block_start->label());
   }
   if (instr->IsGapMoves()) {
     // Handle parallel moves associated with the gap instruction.
     AssembleGap(GapInstruction::cast(instr));
   } else if (instr->IsSourcePosition()) {
     AssembleSourcePosition(SourcePositionInstruction::cast(instr));
   } else {
@@ skipping 384 matching lines @@
 }
 
 
 void CodeGenerator::AddNopForSmiCodeInlining() { UNIMPLEMENTED(); }
 
 #endif  // !V8_TURBOFAN_BACKEND
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8