Implement fixpoint iteration for escape analysis.

src/hydrogen-instructions.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 2307 matching lines @@
     HValue* value = values()->at(i);
     if (HasAssignedIndexAt(i)) {
       env->Bind(GetAssignedIndexAt(i), value);
     } else {
       env->Push(value);
     }
   }
 }
 
 
+static void ReplayEnvironmentNested(const ZoneList<HValue*>* values,
+                                    HCapturedObject* other) {
+  for (int i = 0; i < values->length(); ++i) {
+    HValue* value = values->at(i);
+    if (value->IsCapturedObject()) {
+      if (HCapturedObject::cast(value)->capture_id() == other->capture_id()) {
+        values->at(i) = other;
+      } else {
+        ReplayEnvironmentNested(HCapturedObject::cast(value)->values(), other);
+      }
+    }
+  }
+}
+
+
 // Replay captured objects by replacing all captured objects with the
 // same capture id in the current and all outer environments.
 void HCapturedObject::ReplayEnvironment(HEnvironment* env) {
   ASSERT(env != NULL);
   while (env != NULL) {
-    for (int i = 0; i < env->length(); ++i) {
-      HValue* value = env->values()->at(i);
-      if (value->IsCapturedObject() &&
-          HCapturedObject::cast(value)->capture_id() == this->capture_id()) {
-        env->SetValueAt(i, this);
-      }
-    }
+    ReplayEnvironmentNested(env->values(), this);
     env = env->outer();
   }
 }
 
 
+void HCapturedObject::PrintDataTo(StringStream* stream) {
+  stream->Add("#%d ", capture_id());
+  HDematerializedObject::PrintDataTo(stream);
+}
+
+
 void HEnterInlined::RegisterReturnTarget(HBasicBlock* return_target,
                                          Zone* zone) {
   ASSERT(return_target->IsInlineReturnTarget());
   return_targets_.Add(return_target, zone);
 }
 
 
 void HEnterInlined::PrintDataTo(StringStream* stream) {
   SmartArrayPointer<char> name = function()->debug_name()->ToCString();
   stream->Add("%s, id=%d", *name, function()->id().ToInt());
@@ skipping 1844 matching lines @@
       break;
     case kExternalMemory:
       stream->Add("[external-memory]");
       break;
   }
 
   stream->Add("@%d", offset());
 }
 
 } }  // namespace v8::internal