Add tool to visualize machine code/lithium.

src/x64/lithium-codegen-x64.cc

Index: src/x64/lithium-codegen-x64.cc
diff --git a/src/x64/lithium-codegen-x64.cc b/src/x64/lithium-codegen-x64.cc
index 908d0acf826e72f23301d90ab114d30e6d7bd27e..c82ef8d81b3c9274672970b06642aea6884d29e6 100644
--- a/src/x64/lithium-codegen-x64.cc
+++ b/src/x64/lithium-codegen-x64.cc
@@ -299,8 +299,9 @@ bool LCodeGen::GenerateDeferredCode() {
     for (int i = 0; !is_aborted() && i < deferred_.length(); i++) {
       LDeferredCode* code = deferred_[i];
 
-      int pos = instructions_->at(code->instruction_index())->position();
-      RecordAndUpdatePosition(pos);
+      HValue* value =
+          instructions_->at(code->instruction_index())->hydrogen_value();
+      RecordAndWritePosition(value->position());
 
       Comment(";;; <@%d,#%d> "
               "-------------------- Deferred %s --------------------",
@@ -563,8 +564,6 @@ void LCodeGen::CallCodeGeneric(Handle<Code> code,
                                int argc) {
   EnsureSpaceForLazyDeopt(Deoptimizer::patch_size() - masm()->CallSize(code));
   ASSERT(instr != NULL);
-  LPointerMap* pointers = instr->pointer_map();
-  RecordPosition(pointers->position());
   __ call(code, mode);
   RecordSafepointWithLazyDeopt(instr, safepoint_mode, argc);
 
@@ -590,8 +589,6 @@ void LCodeGen::CallRuntime(const Runtime::Function* function,
                            SaveFPRegsMode save_doubles) {
   ASSERT(instr != NULL);
   ASSERT(instr->HasPointerMap());
-  LPointerMap* pointers = instr->pointer_map();
-  RecordPosition(pointers->position());
 
   __ CallRuntime(function, num_arguments, save_doubles);
 
@@ -840,7 +837,7 @@ void LCodeGen::RecordSafepoint(LPointerMap* pointers,
 
 
 void LCodeGen::RecordSafepoint(Safepoint::DeoptMode deopt_mode) {
-  LPointerMap empty_pointers(RelocInfo::kNoPosition, zone());
+  LPointerMap empty_pointers(zone());
   RecordSafepoint(&empty_pointers, deopt_mode);
 }
 
@@ -852,17 +849,10 @@ void LCodeGen::RecordSafepointWithRegisters(LPointerMap* pointers,
 }
 
 
-void LCodeGen::RecordPosition(int position) {
+void LCodeGen::RecordAndWritePosition(int position) {
   if (position == RelocInfo::kNoPosition) return;
   masm()->positions_recorder()->RecordPosition(position);
-}
-
-
-void LCodeGen::RecordAndUpdatePosition(int position) {
-  if (position >= 0 && position != old_position_) {
-    masm()->positions_recorder()->RecordPosition(position);
-    old_position_ = position;
-  }
+  masm()->positions_recorder()->WriteRecordedPositions();
 }
 
 
@@ -3176,7 +3166,6 @@ void LCodeGen::DoApplyArguments(LApplyArguments* instr) {
   __ bind(&invoke);
   ASSERT(instr->HasPointerMap());
   LPointerMap* pointers = instr->pointer_map();
-  RecordPosition(pointers->position());
   SafepointGenerator safepoint_generator(
       this, pointers, Safepoint::kLazyDeopt);
   ParameterCount actual(rax);
@@ -3250,7 +3239,6 @@ void LCodeGen::CallKnownFunction(Handle<JSFunction> function,
       dont_adapt_arguments || formal_parameter_count == arity;
 
   LPointerMap* pointers = instr->pointer_map();
-  RecordPosition(pointers->position());
 
   if (can_invoke_directly) {
     if (rdi_state == RDI_UNINITIALIZED) {
@@ -3736,7 +3724,6 @@ void LCodeGen::DoInvokeFunction(LInvokeFunction* instr) {
   Handle<JSFunction> known_function = instr->hydrogen()->known_function();
   if (known_function.is_null()) {
     LPointerMap* pointers = instr->pointer_map();
-    RecordPosition(pointers->position());
     SafepointGenerator generator(this, pointers, Safepoint::kLazyDeopt);
     ParameterCount count(instr->arity());
     __ InvokeFunction(rdi, count, CALL_FUNCTION, generator, CALL_AS_METHOD);