Introduce IR and parser support for ML functions.
Representing function arguments is still TODO.
Supporting instructions other than return is also TODO.

PiperOrigin-RevId: 202570934
diff --git a/lib/IR/Function.cpp b/lib/IR/Function.cpp
index 833c173..3af2a61 100644
--- a/lib/IR/Function.cpp
+++ b/lib/IR/Function.cpp
@@ -16,6 +16,7 @@
 // =============================================================================
 
 #include "mlir/IR/CFGFunction.h"
+#include "mlir/IR/MLFunction.h"
 #include "llvm/ADT/StringRef.h"
 using namespace mlir;
 
@@ -38,3 +39,11 @@
 CFGFunction::CFGFunction(StringRef name, FunctionType *type)
   : Function(name, type, Kind::CFGFunc) {
 }
+
+//===----------------------------------------------------------------------===//
+// MLFunction implementation.
+//===----------------------------------------------------------------------===//
+
+MLFunction::MLFunction(StringRef name, FunctionType *type)
+  : Function(name, type, Kind::MLFunc) {
+}