--- a/lib/IR/Comdat.cpp	Sat Feb 17 09:57:20 2018 +0900
+++ b/lib/IR/Comdat.cpp	Wed Aug 14 16:55:33 2019 +0900
@@ -1,19 +1,21 @@
 //===- Comdat.cpp - Implement Metadata classes ----------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
+// 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 implements the Comdat class.
+// This file implements the Comdat class (including the C bindings).
 //
 //===----------------------------------------------------------------------===//
 
-#include "llvm/IR/Comdat.h"
+#include "llvm-c/Comdat.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/StringRef.h"
+#include "llvm/IR/Comdat.h"
+#include "llvm/IR/GlobalObject.h"
+#include "llvm/IR/Module.h"
 
 using namespace llvm;
 
@@ -22,3 +24,54 @@
 Comdat::Comdat() = default;
 
 StringRef Comdat::getName() const { return Name->first(); }
+
+LLVMComdatRef LLVMGetOrInsertComdat(LLVMModuleRef M, const char *Name) {
+  return wrap(unwrap(M)->getOrInsertComdat(Name));
+}
+
+LLVMComdatRef LLVMGetComdat(LLVMValueRef V) {
+  GlobalObject *G = unwrap<GlobalObject>(V);
+  return wrap(G->getComdat());
+}
+
+void LLVMSetComdat(LLVMValueRef V, LLVMComdatRef C) {
+  GlobalObject *G = unwrap<GlobalObject>(V);
+  G->setComdat(unwrap(C));
+}
+
+LLVMComdatSelectionKind LLVMGetComdatSelectionKind(LLVMComdatRef C) {
+  switch (unwrap(C)->getSelectionKind()) {
+  case Comdat::Any:
+    return LLVMAnyComdatSelectionKind;
+  case Comdat::ExactMatch:
+    return LLVMExactMatchComdatSelectionKind;
+  case Comdat::Largest:
+    return LLVMLargestComdatSelectionKind;
+  case Comdat::NoDuplicates:
+    return LLVMNoDuplicatesComdatSelectionKind;
+  case Comdat::SameSize:
+    return LLVMSameSizeComdatSelectionKind;
+  }
+  llvm_unreachable("Invalid Comdat SelectionKind!");
+}
+
+void LLVMSetComdatSelectionKind(LLVMComdatRef C, LLVMComdatSelectionKind kind) {
+  Comdat *Cd = unwrap(C);
+  switch (kind) {
+  case LLVMAnyComdatSelectionKind:
+    Cd->setSelectionKind(Comdat::Any);
+    break;
+  case LLVMExactMatchComdatSelectionKind:
+    Cd->setSelectionKind(Comdat::ExactMatch);
+    break;
+  case LLVMLargestComdatSelectionKind:
+    Cd->setSelectionKind(Comdat::Largest);
+    break;
+  case LLVMNoDuplicatesComdatSelectionKind:
+    Cd->setSelectionKind(Comdat::NoDuplicates);
+    break;
+  case LLVMSameSizeComdatSelectionKind:
+    Cd->setSelectionKind(Comdat::SameSize);
+    break;
+  }
+}