llvm/examples/OrcV2Examples/LLJITWithGDBRegistrationListener/LLJITWithGDBRegistrationListener.cpp

   1 //===--------------- LLJITWithGDBRegistrationListener.cpp -----------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file shows how to switch LLJIT to use a custom object linking layer (we
  10 // use ObjectLinkingLayer, which is backed by JITLink, as an example).
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/ADT/StringMap.h"
  15 #include "llvm/ExecutionEngine/JITEventListener.h"
  16 #include "llvm/ExecutionEngine/JITLink/JITLinkMemoryManager.h"
  17 #include "llvm/ExecutionEngine/Orc/ExecutionUtils.h"
  18 #include "llvm/ExecutionEngine/Orc/LLJIT.h"
  19 #include "llvm/ExecutionEngine/Orc/RTDyldObjectLinkingLayer.h"
  20 #include "llvm/ExecutionEngine/Orc/TargetProcess/TargetExecutionUtils.h"
  21 #include "llvm/ExecutionEngine/SectionMemoryManager.h"
  22 #include "llvm/Support/InitLLVM.h"
  23 #include "llvm/Support/TargetSelect.h"
  24 #include "llvm/Support/raw_ostream.h"
  25
  26 #include "../ExampleModules.h"
  27
  28 using namespace llvm;
  29 using namespace llvm::orc;
  30
  31 ExitOnError ExitOnErr;
  32
  33 static cl::opt<std::string>
  34     EntryPointName("entry", cl::desc("Symbol to call as main entry point"),
  35                    cl::init("main"));
  36
  37 static cl::list<std::string> InputFiles(cl::Positional, cl::OneOrMore,
  38                                         cl::desc("input files"));
  39
  40 static cl::list<std::string> InputArgv("args", cl::Positional,
  41                                        cl::desc("<program arguments>..."),
  42                                        cl::PositionalEatsArgs);
  43
  44 int main(int argc, char *argv[]) {
  45   // Initialize LLVM.
  46   InitLLVM X(argc, argv);
  47
  48   InitializeNativeTarget();
  49   InitializeNativeTargetAsmPrinter();
  50
  51   cl::ParseCommandLineOptions(argc, argv, "LLJITWithGDBRegistrationListener");
  52   ExitOnErr.setBanner(std::string(argv[0]) + ": ");
  53
  54   // Detect the host and set code model to small.
  55   auto JTMB = ExitOnErr(JITTargetMachineBuilder::detectHost());
  56   if (!JTMB.getTargetTriple().isOSLinux())
  57     errs()
  58         << "Warning: This demo may not work for platforms other than Linux.\n";
  59
  60   // Create an LLJIT instance and use a custom object linking layer creator to
  61   // register the GDBRegistrationListener with our RTDyldObjectLinkingLayer.
  62   auto J =
  63       ExitOnErr(LLJITBuilder()
  64                     .setJITTargetMachineBuilder(std::move(JTMB))
  65                     .setObjectLinkingLayerCreator([&](ExecutionSession &ES,
  66                                                       const Triple &TT) {
  67                       auto GetMemMgr = []() {
  68                         return std::make_unique<SectionMemoryManager>();
  69                       };
  70                       auto ObjLinkingLayer =
  71                           std::make_unique<RTDyldObjectLinkingLayer>(
  72                               ES, std::move(GetMemMgr));
  73
  74                       // Register the event listener.
  75                       ObjLinkingLayer->registerJITEventListener(
  76                           *JITEventListener::createGDBRegistrationListener());
  77
  78                       // Make sure the debug info sections aren't stripped.
  79                       ObjLinkingLayer->setProcessAllSections(true);
  80
  81                       return ObjLinkingLayer;
  82                     })
  83                     .create());
  84
  85   // Load the input modules.
  86   for (auto &InputFile : InputFiles) {
  87     auto Ctx = std::make_unique<LLVMContext>();
  88     SMDiagnostic Err;
  89     std::unique_ptr<Module> M = parseIRFile(InputFile, Err, *Ctx);
  90     if (!M) {
  91       Err.print(argv[0], errs());
  92       return 1;
  93     }
  94
  95     ExitOnErr(J->addIRModule(ThreadSafeModule(std::move(M), std::move(Ctx))));
  96   }
  97
  98   // Look up the entry point, cast it to a C main function pointer, then use
  99   // runAsMain to call it.
 100   auto EntryAddr = ExitOnErr(J->lookup(EntryPointName));
 101   auto EntryFn = EntryAddr.toPtr<int(int, char *[])>();
 102
 103   return runAsMain(EntryFn, InputArgv, StringRef(InputFiles.front()));
 104 }