[compiler] Introduce StringEqualStub and StringNotEqualStub.

src/compiler/simplified-lowering.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/simplified-lowering.h"
 
 #include <limits>
 
 #include "src/base/bits.h"
 #include "src/code-factory.h"
@@ skipping 276 matching lines @@
 
     static NodeOutputInfo Uint64() {
       // TODO(jarin) Fix once we have a real uint64 type.
       return NodeOutputInfo(MachineRepresentation::kWord64, Type::Internal());
     }
 
     static NodeOutputInfo AnyTagged() {
       return NodeOutputInfo(MachineRepresentation::kTagged, Type::Any());
     }
 
+    static NodeOutputInfo BoolTagged() {
+      return NodeOutputInfo(MachineRepresentation::kTagged, Type::Boolean());
+    }
+
     static NodeOutputInfo NumberTagged() {
       return NodeOutputInfo(MachineRepresentation::kTagged, Type::Number());
     }
 
     static NodeOutputInfo Pointer() {
       return NodeOutputInfo(MachineType::PointerRepresentation(), Type::Any());
     }
 
    private:
     Type* type_;
@@ skipping 825 matching lines @@
         break;
       }
       case IrOpcode::kReferenceEqual: {
         VisitBinop(node, UseInfo::AnyTagged(), NodeOutputInfo::Bool());
         if (lower()) {
           NodeProperties::ChangeOp(node, lowering->machine()->WordEqual());
         }
         break;
       }
       case IrOpcode::kStringEqual: {
-        VisitBinop(node, UseInfo::AnyTagged(), NodeOutputInfo::Bool());
-        if (lower()) lowering->DoStringEqual(node);
+        VisitBinop(node, UseInfo::AnyTagged(), NodeOutputInfo::BoolTagged());
+        if (lower()) {
+          // StringEqual(x, y) => Call(StringEqualStub, x, y, no-context)
+          Operator::Properties properties = node->op()->properties();
+          Callable callable = CodeFactory::StringEqual(jsgraph_->isolate());
+          CallDescriptor::Flags flags = CallDescriptor::kNoFlags;
+          CallDescriptor* desc = Linkage::GetStubCallDescriptor(
+              jsgraph_->isolate(), jsgraph_->zone(), callable.descriptor(), 0,
+              flags, properties);
+          node->InsertInput(jsgraph_->zone(), 0,
+                            jsgraph_->HeapConstant(callable.code()));
+          node->InsertInput(jsgraph_->zone(), 3, jsgraph_->NoContextConstant());
+          NodeProperties::ChangeOp(node, jsgraph_->common()->Call(desc));
+        }
         break;
       }
       case IrOpcode::kStringLessThan: {
         VisitBinop(node, UseInfo::AnyTagged(), NodeOutputInfo::Bool());
         if (lower()) lowering->DoStringLessThan(node);
         break;
       }
       case IrOpcode::kStringLessThanOrEqual: {
         VisitBinop(node, UseInfo::AnyTagged(), NodeOutputInfo::Bool());
         if (lower()) lowering->DoStringLessThanOrEqual(node);
@@ skipping 729 matching lines @@
       edge.UpdateTo(replacement);
     } else {
       DCHECK(NodeProperties::IsValueEdge(edge));
     }
   }
 }
 
 }  // namespace
 
 
-void SimplifiedLowering::DoStringEqual(Node* node) {
-  Node* comparison = StringComparison(node);
-  ReplaceEffectUses(node, comparison);
-  node->ReplaceInput(0, comparison);
-  node->ReplaceInput(1, jsgraph()->SmiConstant(EQUAL));
-  node->TrimInputCount(2);
-  NodeProperties::ChangeOp(node, machine()->WordEqual());
-}
-
-
 void SimplifiedLowering::DoStringLessThan(Node* node) {
   Node* comparison = StringComparison(node);
   ReplaceEffectUses(node, comparison);
   node->ReplaceInput(0, comparison);
   node->ReplaceInput(1, jsgraph()->SmiConstant(EQUAL));
   node->TrimInputCount(2);
   NodeProperties::ChangeOp(node, machine()->IntLessThan());
 }
 
 
 void SimplifiedLowering::DoStringLessThanOrEqual(Node* node) {
   Node* comparison = StringComparison(node);
   ReplaceEffectUses(node, comparison);
   node->ReplaceInput(0, comparison);
   node->ReplaceInput(1, jsgraph()->SmiConstant(EQUAL));
   node->TrimInputCount(2);
   NodeProperties::ChangeOp(node, machine()->IntLessThanOrEqual());
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8