X64: Made simpler version of fast-smi-loop code.

src/x64/codegen-x64.h

Index: src/x64/codegen-x64.h
diff --git a/src/x64/codegen-x64.h b/src/x64/codegen-x64.h
index cd03d2acc12d1a6c6ca2b9db7d5329fa3c87ce50..b9a3b706313489f12c22427e28cbd9b5317f32c5 100644
--- a/src/x64/codegen-x64.h
+++ b/src/x64/codegen-x64.h
@@ -393,6 +393,9 @@ class CodeGenerator: public AstVisitor {
   // target (which can not be done more than once).
   void GenerateReturnSequence(Result* return_value);
 
+  // Generate code for a fast smi loop.
+  void GenerateFastSmiLoop(ForStatement* node);
+
   // Returns the arguments allocation mode.
   ArgumentsAllocationMode ArgumentsMode();