Index: include/llvm/Support/Casting.h
===================================================================
--- include/llvm/Support/Casting.h
+++ include/llvm/Support/Casting.h
@@ -18,6 +18,7 @@
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/type_traits.h"
 #include <cassert>
+#include <memory>
 
 namespace llvm {
 
@@ -47,6 +48,30 @@
   }
 };
 
+template<class T> struct simplify_type<std::unique_ptr<T>> {
+  typedef T* SimpleType;
+  static SimpleType getSimplifiedValue(std::unique_ptr<T> &Val) { return Val.get(); }
+};
+
+template<class T> struct simplify_type<const std::unique_ptr<T>> {
+  typedef /*const*/ T* SimpleType;
+  static SimpleType getSimplifiedValue(const std::unique_ptr<T> &Val) {
+    return Val.get();
+  }
+};
+
+template<class T> struct simplify_type<std::shared_ptr<T>> {
+  typedef T* SimpleType;
+  static SimpleType getSimplifiedValue(std::shared_ptr<T> &Val) { return Val.get(); }
+};
+
+template<class T> struct simplify_type<const std::shared_ptr<T>> {
+  typedef /*const*/ T* SimpleType;
+  static SimpleType getSimplifiedValue(const std::shared_ptr<T> &Val) {
+    return Val.get();
+  }
+};
+
 // The core of the implementation of isa<X> is here; To and From should be
 // the names of classes.  This template can be specialized to customize the
 // implementation of isa<> without rewriting it from scratch.
Index: unittests/Support/Casting.cpp
===================================================================
--- unittests/Support/Casting.cpp
+++ unittests/Support/Casting.cpp
@@ -165,6 +165,26 @@
   EXPECT_NE(F5, null_foo);
 }
 
+// We should be able to treat unique_ptr<T> just like T* for the purposes of
+// isa, dyn_cast, cast, etc.
+TEST(CastingTest, unique_ptr) {
+  std::unique_ptr<foo> a(new foo());
+  EXPECT_TRUE(isa<foo>(a));
+
+  std::unique_ptr<bar> b(new bar());
+  EXPECT_NE(dyn_cast_or_null<foo>(b), null_foo);
+}
+
+// We should be able to treat shared_ptr<T> just like T* for the purposes of
+// isa, dyn_cast, cast, etc.
+TEST(CastingTest, shared_ptr) {
+  auto a = std::make_shared<foo>();
+  EXPECT_TRUE(isa<foo>(a));
+
+  auto b = std::make_shared<bar>();
+  EXPECT_NE(dyn_cast_or_null<foo>(b), null_foo);
+}
+
 // These lines are errors...
 //foo *F20 = cast<foo>(B2);  // Yields const foo*
 //foo &F21 = cast<foo>(B3);  // Yields const foo&