1 files changed, 51 insertions, 0 deletions
diff --git a/third_party/llvm-project/include/llvm/Support/Printable.h b/third_party/llvm-project/include/llvm/Support/Printable.h
new file mode 100644
index 000000000..0f8670d04
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+++ b/third_party/llvm-project/include/llvm/Support/Printable.h
@@ -0,0 +1,51 @@
+//===--- Printable.h - Print function helpers -------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines the Printable struct.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_SUPPORT_PRINTABLE_H
+#define LLVM_SUPPORT_PRINTABLE_H
+
+#include <functional>
+
+namespace llvm {
+
+class raw_ostream;
+
+/// Simple wrapper around std::function<void(raw_ostream&)>.
+/// This class is useful to construct print helpers for raw_ostream.
+///
+/// Example:
+///     Printable PrintRegister(unsigned Register) {
+///       return Printable([Register](raw_ostream &OS) {
+///         OS << getRegisterName(Register);
+///       }
+///     }
+///     ... OS << PrintRegister(Register); ...
+///
+/// Implementation note: Ideally this would just be a typedef, but doing so
+/// leads to operator << being ambiguous as function has matching constructors
+/// in some STL versions. I have seen the problem on gcc 4.6 libstdc++ and
+/// microsoft STL.
+class Printable {
+public:
+  std::function<void(raw_ostream &OS)> Print;
+  Printable(std::function<void(raw_ostream &OS)> Print)
+      : Print(std::move(Print)) {}
+};
+
+inline raw_ostream &operator<<(raw_ostream &OS, const Printable &P) {
+  P.Print(OS);
+  return OS;
+}
+
+}
+
+#endif