Implemented the ctz Turbo Fan operator for x64.

src/compiler/typer.cc

Index: src/compiler/typer.cc
diff --git a/src/compiler/typer.cc b/src/compiler/typer.cc
index d4fc9b648b5aae8350b71f5a7bf0d214fd82f26d..5c021270b83682f64180b44c38f59e853c61d990 100644
--- a/src/compiler/typer.cc
+++ b/src/compiler/typer.cc
@@ -1958,6 +1958,9 @@ Type* Typer::Visitor::TypeWord64Ror(Node* node) { return Type::Internal(); }
 Type* Typer::Visitor::TypeWord64Clz(Node* node) { return Type::Internal(); }
 
 
+Type* Typer::Visitor::TypeWord64Ctz(Node* node) { return Type::Internal(); }
+
+
 Type* Typer::Visitor::TypeWord64Equal(Node* node) { return Type::Boolean(); }