[stubs] Introduce AddStub and SubtractStub.

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 157 matching lines @@
   }
   return result;
 }
 
 Node* CodeStubAssembler::SmiToFloat64(Node* value) {
   return ChangeInt32ToFloat64(SmiUntag(value));
 }
 
 Node* CodeStubAssembler::SmiAdd(Node* a, Node* b) { return IntPtrAdd(a, b); }
 
+Node* CodeStubAssembler::SmiAddWithOverflow(Node* a, Node* b) {
+  return IntPtrAddWithOverflow(a, b);
+}
+
+Node* CodeStubAssembler::SmiSub(Node* a, Node* b) { return IntPtrSub(a, b); }
+
+Node* CodeStubAssembler::SmiSubWithOverflow(Node* a, Node* b) {
+  return IntPtrSubWithOverflow(a, b);
+}
+
 Node* CodeStubAssembler::SmiEqual(Node* a, Node* b) { return WordEqual(a, b); }
 
 Node* CodeStubAssembler::SmiLessThan(Node* a, Node* b) {
   return IntPtrLessThan(a, b);
 }
 
 Node* CodeStubAssembler::SmiLessThanOrEqual(Node* a, Node* b) {
   return IntPtrLessThanOrEqual(a, b);
 }
 
@@ skipping 705 matching lines @@
       }
     }
   }
 
   bound_ = true;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8