[turbofan] Deopt support for escape analysis

src/compiler/escape-analysis-reducer.cc

 // Copyright 2015 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/escape-analysis-reducer.h"
 
 #include "src/compiler/js-graph.h"
 #include "src/compiler/js-operator.h"
 
 namespace v8 {
@@ skipping 17 matching lines @@
     case IrOpcode::kStoreField:
       return ReduceStoreField(node);
     case IrOpcode::kAllocate:
       return ReduceAllocate(node);
     case IrOpcode::kFinishRegion:
       return ReduceFinishRegion(node);
     case IrOpcode::kReferenceEqual:
       return ReduceReferenceEqual(node);
     case IrOpcode::kStateValues:
     case IrOpcode::kFrameState:
-      return ReplaceWithDeoptDummy(node);
+      return ReduceStateValueInputs(node);
     default:
       break;
   }
   return NoChange();
 }
 
 
 Reduction EscapeAnalysisReducer::ReduceLoadField(Node* node) {
   DCHECK_EQ(node->opcode(), IrOpcode::kLoadField);
   if (Node* rep = escape_analysis()->GetReplacement(node, node->id())) {
@@ skipping 85 matching lines @@
     // Left-hand side is not a virtual object.
     ReplaceWithValue(node, jsgraph()->FalseConstant());
     if (FLAG_trace_turbo_escape) {
       PrintF("Replaced ref eq #%d with false\n", node->id());
     }
   }
   return NoChange();
 }
 
 
-// TODO(sigurds): This is a temporary solution until escape analysis
-// supports deoptimization.
-Reduction EscapeAnalysisReducer::ReplaceWithDeoptDummy(Node* node) {
+void EscapeAnalysisReducer::CreateObjectState(Node* effect, Node* node) {
+  if ((node->opcode() == IrOpcode::kFinishRegion ||
+       node->opcode() == IrOpcode::kAllocate) &&
+      escape_status()->IsVirtual(node)) {
+    VirtualObject* vobj =
+        escape_analysis()->GetVirtualObject(effect, node->id());
+    if (!vobj->GetObjectState()) {
+      DCHECK_NOT_NULL(vobj);
+      Node* obj_state = jsgraph()->graph()->NewNode(
+          jsgraph()->common()->ObjectState(static_cast<int>(vobj->fields()),
+                                           vobj->id()),
+          static_cast<int>(vobj->fields()), vobj->fields_array());
+      vobj->SetObjectState(obj_state);
+      // Now fix uses of other objects.
+      for (size_t i = 0; i < vobj->fields(); ++i) {
+        if (Node* field = vobj->GetField(i)) {
+          CreateObjectState(effect, field);
+          VirtualObject* vobj =
+              escape_analysis()->GetVirtualObject(effect, field->id());
+          if (vobj && vobj->GetObjectState()) {
+            NodeProperties::ReplaceValueInput(obj_state, vobj->GetObjectState(),
+                                              static_cast<int>(i));
+          }
+        }
+      }
+    }
+  }
+}
+
+
+Reduction EscapeAnalysisReducer::ReduceStateValueInputs(Node* node) {
   DCHECK(node->opcode() == IrOpcode::kStateValues ||
          node->opcode() == IrOpcode::kFrameState);
+  Node* effect = escape_analysis()->GetEffect(node);
+  DCHECK_NOT_NULL(effect);
   Reduction r = NoChange();
   for (int i = 0; i < node->op()->ValueInputCount(); ++i) {
     Node* input = NodeProperties::GetValueInput(node, i);
     if (input->opcode() == IrOpcode::kFinishRegion ||
-        input->opcode() == IrOpcode::kAllocate ||
-        input->opcode() == IrOpcode::kPhi) {
+        input->opcode() == IrOpcode::kAllocate) {
       if (escape_status()->IsVirtual(input)) {
-        NodeProperties::ReplaceValueInput(node, jsgraph()->UndefinedConstant(),
-                                          i);
+        CreateObjectState(effect, input);

[Jarin, 2015/12/02 12:24:34]

Nit: could not you return the ObjectState from CreateObjectState?

[sigurds, 2015/12/02 16:35:12]

Done.

+        VirtualObject* vobj =
+            escape_analysis()->GetVirtualObject(effect, input->id());
+        NodeProperties::ReplaceValueInput(node, vobj->GetObjectState(), i);
         if (FLAG_trace_turbo_escape) {
-          PrintF("Replaced state value (#%d) input with dummy\n", node->id());
+          PrintF("Replaced state value (#%d) input with object state #%d\n",
+                 node->id(), vobj->GetObjectState()->id());
         }
         r = Changed(node);
       }
     }
   }
   return r;
 }
 
-
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8