[compiler] Introduce StringEqualStub and StringNotEqualStub.

src/compiler/code-stub-assembler.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/code-stub-assembler.h"
 
 #include <ostream>
 
 #include "src/code-factory.h"
 #include "src/compiler/graph.h"
@@ skipping 584 matching lines @@
   args[0] = arg1;
   args[1] = arg2;
   args[2] = arg3;
   args[3] = arg4;
   args[4] = arg5;
   args[5] = context;
 
   return CallN(call_descriptor, target, args);
 }
 
+Node* CodeStubAssembler::TailCallStub(Callable const& callable, Node* context,
+                                      Node* arg1, Node* arg2,
+                                      size_t result_size) {
+  Node* target = HeapConstant(callable.code());
+  return TailCallStub(callable.descriptor(), target, context, arg1, arg2,
+                      result_size);
+}
+
 Node* CodeStubAssembler::TailCallStub(const CallInterfaceDescriptor& descriptor,
                                       Node* target, Node* context, Node* arg1,
                                       Node* arg2, size_t result_size) {
   CallDescriptor* call_descriptor = Linkage::GetStubCallDescriptor(
       isolate(), zone(), descriptor, descriptor.GetStackParameterCount(),
       CallDescriptor::kSupportsTailCalls, Operator::kNoProperties,
       MachineType::AnyTagged(), result_size);
 
   Node** args = zone()->NewArray<Node*>(3);
   args[0] = arg1;
@@ skipping 204 matching lines @@
       }
     }
   }
 
   bound_ = true;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8