3 files changed, 82 insertions, 0 deletions
diff --git a/llvm/examples/LLJITExamples/CMakeLists.txt b/llvm/examples/LLJITExamples/CMakeLists.txt
index 2ca888e3054..d1d53028f89 100644
--- a/llvm/examples/LLJITExamples/CMakeLists.txt
+++ b/llvm/examples/LLJITExamples/CMakeLists.txt
@@ -1 +1,2 @@
 add_subdirectory(LLJITWithObjectCache)
+add_subdirectory(LLJITWithJITLink)
diff --git a/llvm/examples/LLJITExamples/LLJITWithJITLink/CMakeLists.txt b/llvm/examples/LLJITExamples/LLJITWithJITLink/CMakeLists.txt
new file mode 100644
index 00000000000..5f9bf394a72
--- /dev/null
+++ b/llvm/examples/LLJITExamples/LLJITWithJITLink/CMakeLists.txt
@@ -0,0 +1,11 @@
+set(LLVM_LINK_COMPONENTS
+  Core
+  IRReader
+  OrcJIT
+  Support
+  nativecodegen
+  )
+
+add_llvm_example(LLJITWithJITLink
+  LLJITWithJITLink.cpp
+  )
diff --git a/llvm/examples/LLJITExamples/LLJITWithJITLink/LLJITWithJITLink.cpp b/llvm/examples/LLJITExamples/LLJITWithJITLink/LLJITWithJITLink.cpp
new file mode 100644
index 00000000000..ed79b90e328
--- /dev/null
+++ b/llvm/examples/LLJITExamples/LLJITWithJITLink/LLJITWithJITLink.cpp
@@ -0,0 +1,70 @@
+//===-- LLJITWithJITLink.cpp - Configure LLJIT to use ObjectLinkingLayer --===//
+//
+// 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 shows how to switch LLJIT to use ObjectLinkingLayer (which is
+// backed by JITLink) rather than RTDyldObjectLinkingLayer (which is backed by
+// RuntimeDyld). Using JITLink as the underlying allocator enables use of
+// small code model in JIT'd code.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/StringMap.h"
+#include "llvm/ExecutionEngine/JITLink/JITLinkMemoryManager.h"
+#include "llvm/ExecutionEngine/Orc/LLJIT.h"
+#include "llvm/ExecutionEngine/Orc/ObjectLinkingLayer.h"
+#include "llvm/Support/InitLLVM.h"
+#include "llvm/Support/TargetSelect.h"
+#include "llvm/Support/raw_ostream.h"
+
+#include "../ExampleModules.h"
+
+using namespace llvm;
+using namespace llvm::orc;
+
+ExitOnError ExitOnErr;
+
+int main(int argc, char *argv[]) {
+  // Initialize LLVM.
+  InitLLVM X(argc, argv);
+
+  InitializeNativeTarget();
+  InitializeNativeTargetAsmPrinter();
+
+  cl::ParseCommandLineOptions(argc, argv, "HowToUseLLJIT");
+  ExitOnErr.setBanner(std::string(argv[0]) + ": ");
+
+  // Declare an in-process JITLink memory manager.
+  jitlink::InProcessMemoryManager MemMgr;
+
+  // Detect the host and set code model to small.
+  auto JTMB = ExitOnErr(JITTargetMachineBuilder::detectHost());
+  JTMB.setCodeModel(CodeModel::Small);
+
+  // Create an LLJIT instance with a custom CompileFunction.
+  auto J =
+      ExitOnErr(LLJITBuilder()
+                    .setJITTargetMachineBuilder(std::move(JTMB))
+                    .setObjectLinkingLayerCreator([&](ExecutionSession &ES,
+                                                      const Triple &TT) {
+                      return std::make_unique<ObjectLinkingLayer>(ES, MemMgr);
+                    })
+                    .create());
+
+  auto M = ExitOnErr(parseExampleModule(Add1Example, "add1"));
+
+  ExitOnErr(J->addIRModule(std::move(M)));
+
+  // Look up the JIT'd function, cast it to a function pointer, then call it.
+  auto Add1Sym = ExitOnErr(J->lookup("add1"));
+  int (*Add1)(int) = (int (*)(int))Add1Sym.getAddress();
+
+  int Result = Add1(42);
+  outs() << "add1(42) = " << Result << "\n";
+
+  return 0;
+}