diff --git a/llvm/include/llvm/Support/MemoryBuffer.h b/llvm/include/llvm/Support/MemoryBuffer.h
--- a/llvm/include/llvm/Support/MemoryBuffer.h
+++ b/llvm/include/llvm/Support/MemoryBuffer.h
@@ -22,6 +22,7 @@
 #include "llvm/Support/FileSystem.h"
 #include <cstddef>
 #include <cstdint>
+#include <functional>
 #include <memory>
 
 namespace llvm {
@@ -126,6 +127,13 @@
   getFileOrSTDIN(const Twine &Filename, int64_t FileSize = -1,
                  bool RequiresNullTerminator = true);
 
+  /// If Filename is "-" and stdin refers to a terminal, ie input has not been
+  /// redirected in, call TtyStdin then exit with code 1. Otherwise acts the
+  /// same as MemoryBuffer::getFileOrSTDIN(const Twine &, int64_t, bool).
+  static ErrorOr<std::unique_ptr<MemoryBuffer>>
+  getFileOrSTDIN(const Twine &Filename, std::function<void(void)> TtyStdin,
+                 int64_t FileSize = -1, bool RequiresNullTerminator = true);
+
   /// Map a subrange of the specified file as a MemoryBuffer.
   static ErrorOr<std::unique_ptr<MemoryBuffer>>
   getFileSlice(const Twine &Filename, uint64_t MapSize, uint64_t Offset,
diff --git a/llvm/lib/Support/MemoryBuffer.cpp b/llvm/lib/Support/MemoryBuffer.cpp
--- a/llvm/lib/Support/MemoryBuffer.cpp
+++ b/llvm/lib/Support/MemoryBuffer.cpp
@@ -23,6 +23,7 @@
 #include "llvm/Support/SmallVectorMemoryBuffer.h"
 #include <cassert>
 #include <cerrno>
+#include <cstdlib>
 #include <cstring>
 #include <new>
 #include <sys/types.h>
@@ -150,6 +151,23 @@
   return getFile(Filename, FileSize, RequiresNullTerminator);
 }
 
+ErrorOr<std::unique_ptr<MemoryBuffer>>
+MemoryBuffer::getFileOrSTDIN(const Twine &Filename,
+                             std::function<void(void)> TtyStdin,
+                             int64_t FileSize, bool RequiresNullTerminator) {
+  SmallString<256> NameBuf;
+  StringRef NameRef = Filename.toStringRef(NameBuf);
+
+  if (NameRef == "-") {
+    if (sys::fs::is_tty(0)) {
+      TtyStdin();
+      std::exit(1);
+    }
+    return getSTDIN();
+  }
+  return getFile(Filename, FileSize, RequiresNullTerminator);
+}
+
 ErrorOr<std::unique_ptr<MemoryBuffer>>
 MemoryBuffer::getFileSlice(const Twine &FilePath, uint64_t MapSize,
                            uint64_t Offset, bool IsVolatile) {
diff --git a/llvm/unittests/Support/MemoryBufferTest.cpp b/llvm/unittests/Support/MemoryBufferTest.cpp
--- a/llvm/unittests/Support/MemoryBufferTest.cpp
+++ b/llvm/unittests/Support/MemoryBufferTest.cpp
@@ -16,6 +16,7 @@
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Testing/Support/Error.h"
 #include "gtest/gtest.h"
+#include <unistd.h> // for dup2(2)
 
 using namespace llvm;
 
@@ -288,4 +289,37 @@
   ASSERT_EQ(16u, MB.getBufferSize());
   EXPECT_EQ("xxxxxxxxxxxxxxxx", MB.getBuffer());
 }
+
+TEST_F(MemoryBufferTest, getFileOrSTDIN) {
+  int TestForChange = 0;
+  auto ChangeFunc = [&TestForChange] {
+    outs() << "message";
+    TestForChange = 1;
+  };
+  // See if stdin is a tty, otherwise skip this test.
+  if (sys::fs::is_tty(0)) {
+    EXPECT_EXIT(MemoryBuffer::getFileOrSTDIN("-", ChangeFunc),
+                ::testing::ExitedWithCode(1), "message")
+        << "Reading from tty should have exited with exit code 1";
+    ASSERT_EQ(TestForChange, 1) << "Callback not called";
+    TestForChange = 0;
+  }
+
+  auto TempFile = sys::fs::TempFile::create("%%%%%%%%");
+  if (!TempFile)
+    return;
+
+  if (::dup2(TempFile->FD, 0))
+    return;
+
+  if (sys::fs::is_tty(0))
+    return;
+
+  MemoryBuffer::getFileOrSTDIN("-", ChangeFunc);
+  ASSERT_EQ(TestForChange, 0) << "Callback should not have been called";
+
+  // Need to check Error, also need to do something in if or compiler will warn.
+  if (Error E = TempFile->discard())
+    return;
+}
 }