[turbofan] Add support for storing to double fields.

src/compiler/common-operator-reducer.cc

 // Copyright 2014 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/common-operator-reducer.h"
 
 #include <algorithm>
 
 #include "src/compiler/common-operator.h"
 #include "src/compiler/graph.h"
@@ skipping 49 matching lines @@
     case IrOpcode::kMerge:
       return ReduceMerge(node);
     case IrOpcode::kEffectPhi:
       return ReduceEffectPhi(node);
     case IrOpcode::kPhi:
       return ReducePhi(node);
     case IrOpcode::kReturn:
       return ReduceReturn(node);
     case IrOpcode::kSelect:
       return ReduceSelect(node);
+    case IrOpcode::kGuard:
+      return ReduceGuard(node);
     default:
       break;
   }
   return NoChange();
 }
 
 
 Reduction CommonOperatorReducer::ReduceBranch(Node* node) {
   DCHECK_EQ(IrOpcode::kBranch, node->opcode());
   Node* const cond = node->InputAt(0);
@@ skipping 271 matching lines @@
       }
       break;
     }
     default:
       break;
   }
   return NoChange();
 }
 
 
+Reduction CommonOperatorReducer::ReduceGuard(Node* node) {
+  DCHECK_EQ(IrOpcode::kGuard, node->opcode());
+  Node* const input = NodeProperties::GetValueInput(node, 0);
+  Type* const input_type = NodeProperties::GetTypeOrAny(input);
+  Type* const guard_type = OpParameter<Type*>(node);
+  if (input_type->Is(guard_type)) return Replace(input);
+  return NoChange();
+}
+
+
 Reduction CommonOperatorReducer::Change(Node* node, Operator const* op,
                                         Node* a) {
   node->ReplaceInput(0, a);
   node->TrimInputCount(1);
   NodeProperties::ChangeOp(node, op);
   return Changed(node);
 }
 
 
 Reduction CommonOperatorReducer::Change(Node* node, Operator const* op, Node* a,
                                         Node* b) {
   node->ReplaceInput(0, a);
   node->ReplaceInput(1, b);
   node->TrimInputCount(2);
   NodeProperties::ChangeOp(node, op);
   return Changed(node);
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8