Imported Upstream version 6.10.0.49

Former-commit-id: 1d6753294b2993e1fbf92de9366bb9544db4189b

external/llvm-project/clang/examples/clang-interpreter/CMakeLists.txt

@@ -0,0 +1,25 @@
+set(LLVM_LINK_COMPONENTS
+  Core
+  ExecutionEngine
+  MC
+  MCJIT
+  Option
+  Support
+  native
+  )
+
+add_clang_executable(clang-interpreter
+  main.cpp
+  )
+
+add_dependencies(clang-interpreter
+  clang-headers
+  )
+
+target_link_libraries(clang-interpreter
+  PRIVATE
+  clangBasic
+  clangCodeGen
+  clangDriver
+  clangFrontend
+  )

external/llvm-project/clang/examples/clang-interpreter/README.txt

@@ -0,0 +1,17 @@
+This is an example of Clang based interpreter, for executing standalone C
+programs.
+
+It demonstrates the following features:
+ 1. Parsing standard compiler command line arguments using the Driver library.
+
+ 2. Constructing a Clang compiler instance, using the appropriate arguments
+    derived in step #1.
+
+ 3. Invoking the Clang compiler to lex, parse, syntax check, and then generate
+    LLVM code.
+
+ 4. Use the LLVM JIT functionality to execute the final module.
+
+The implementation has many limitations and is not designed to be a full fledged
+C interpreter. It is designed to demonstrate a simple but functional use of the
+Clang compiler libraries.

external/llvm-project/clang/examples/clang-interpreter/main.cpp

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+//===-- examples/clang-interpreter/main.cpp - Clang C Interpreter Example -===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/CodeGen/CodeGenAction.h"
+#include "clang/Basic/DiagnosticOptions.h"
+#include "clang/Driver/Compilation.h"
+#include "clang/Driver/Driver.h"
+#include "clang/Driver/Tool.h"
+#include "clang/Frontend/CompilerInstance.h"
+#include "clang/Frontend/CompilerInvocation.h"
+#include "clang/Frontend/FrontendDiagnostic.h"
+#include "clang/Frontend/TextDiagnosticPrinter.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ExecutionEngine/ExecutionEngine.h"
+#include "llvm/ExecutionEngine/MCJIT.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/Host.h"
+#include "llvm/Support/ManagedStatic.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/TargetSelect.h"
+#include "llvm/Support/raw_ostream.h"
+#include <memory>
+using namespace clang;
+using namespace clang::driver;
+
+// This function isn't referenced outside its translation unit, but it
+// can't use the "static" keyword because its address is used for
+// GetMainExecutable (since some platforms don't support taking the
+// address of main, and some platforms can't implement GetMainExecutable
+// without being given the address of a function in the main executable).
+std::string GetExecutablePath(const char *Argv0) {
+  // This just needs to be some symbol in the binary; C++ doesn't
+  // allow taking the address of ::main however.
+  void *MainAddr = (void*) (intptr_t) GetExecutablePath;
+  return llvm::sys::fs::getMainExecutable(Argv0, MainAddr);
+}
+
+static llvm::ExecutionEngine *
+createExecutionEngine(std::unique_ptr<llvm::Module> M, std::string *ErrorStr) {
+  return llvm::EngineBuilder(std::move(M))
+      .setEngineKind(llvm::EngineKind::Either)
+      .setErrorStr(ErrorStr)
+      .create();
+}
+
+static int Execute(std::unique_ptr<llvm::Module> Mod, char *const *envp) {
+  llvm::InitializeNativeTarget();
+  llvm::InitializeNativeTargetAsmPrinter();
+
+  llvm::Module &M = *Mod;
+  std::string Error;
+  std::unique_ptr<llvm::ExecutionEngine> EE(
+      createExecutionEngine(std::move(Mod), &Error));
+  if (!EE) {
+    llvm::errs() << "unable to make execution engine: " << Error << "\n";
+    return 255;
+  }
+
+  llvm::Function *EntryFn = M.getFunction("main");
+  if (!EntryFn) {
+    llvm::errs() << "'main' function not found in module.\n";
+    return 255;
+  }
+
+  // FIXME: Support passing arguments.
+  std::vector<std::string> Args;
+  Args.push_back(M.getModuleIdentifier());
+
+  EE->finalizeObject();
+  return EE->runFunctionAsMain(EntryFn, Args, envp);
+}
+
+int main(int argc, const char **argv, char * const *envp) {
+  void *MainAddr = (void*) (intptr_t) GetExecutablePath;
+  std::string Path = GetExecutablePath(argv[0]);
+  IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts = new DiagnosticOptions();
+  TextDiagnosticPrinter *DiagClient =
+    new TextDiagnosticPrinter(llvm::errs(), &*DiagOpts);
+
+  IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
+  DiagnosticsEngine Diags(DiagID, &*DiagOpts, DiagClient);
+
+  // Use ELF on windows for now.
+  std::string TripleStr = llvm::sys::getProcessTriple();
+  llvm::Triple T(TripleStr);
+  if (T.isOSBinFormatCOFF())
+    T.setObjectFormat(llvm::Triple::ELF);
+
+  Driver TheDriver(Path, T.str(), Diags);
+  TheDriver.setTitle("clang interpreter");
+  TheDriver.setCheckInputsExist(false);
+
+  // FIXME: This is a hack to try to force the driver to do something we can
+  // recognize. We need to extend the driver library to support this use model
+  // (basically, exactly one input, and the operation mode is hard wired).
+  SmallVector<const char *, 16> Args(argv, argv + argc);
+  Args.push_back("-fsyntax-only");
+  std::unique_ptr<Compilation> C(TheDriver.BuildCompilation(Args));
+  if (!C)
+    return 0;
+
+  // FIXME: This is copied from ASTUnit.cpp; simplify and eliminate.
+
+  // We expect to get back exactly one command job, if we didn't something
+  // failed. Extract that job from the compilation.
+  const driver::JobList &Jobs = C->getJobs();
+  if (Jobs.size() != 1 || !isa<driver::Command>(*Jobs.begin())) {
+    SmallString<256> Msg;
+    llvm::raw_svector_ostream OS(Msg);
+    Jobs.Print(OS, "; ", true);
+    Diags.Report(diag::err_fe_expected_compiler_job) << OS.str();
+    return 1;
+  }
+
+  const driver::Command &Cmd = cast<driver::Command>(*Jobs.begin());
+  if (llvm::StringRef(Cmd.getCreator().getName()) != "clang") {
+    Diags.Report(diag::err_fe_expected_clang_command);
+    return 1;
+  }
+
+  // Initialize a compiler invocation object from the clang (-cc1) arguments.
+  const driver::ArgStringList &CCArgs = Cmd.getArguments();
+  std::unique_ptr<CompilerInvocation> CI(new CompilerInvocation);
+  CompilerInvocation::CreateFromArgs(*CI,
+                                     const_cast<const char **>(CCArgs.data()),
+                                     const_cast<const char **>(CCArgs.data()) +
+                                       CCArgs.size(),
+                                     Diags);
+
+  // Show the invocation, with -v.
+  if (CI->getHeaderSearchOpts().Verbose) {
+    llvm::errs() << "clang invocation:\n";
+    Jobs.Print(llvm::errs(), "\n", true);
+    llvm::errs() << "\n";
+  }
+
+  // FIXME: This is copied from cc1_main.cpp; simplify and eliminate.
+
+  // Create a compiler instance to handle the actual work.
+  CompilerInstance Clang;
+  Clang.setInvocation(std::move(CI));
+
+  // Create the compilers actual diagnostics engine.
+  Clang.createDiagnostics();
+  if (!Clang.hasDiagnostics())
+    return 1;
+
+  // Infer the builtin include path if unspecified.
+  if (Clang.getHeaderSearchOpts().UseBuiltinIncludes &&
+      Clang.getHeaderSearchOpts().ResourceDir.empty())
+    Clang.getHeaderSearchOpts().ResourceDir =
+      CompilerInvocation::GetResourcesPath(argv[0], MainAddr);
+
+  // Create and execute the frontend to generate an LLVM bitcode module.
+  std::unique_ptr<CodeGenAction> Act(new EmitLLVMOnlyAction());
+  if (!Clang.ExecuteAction(*Act))
+    return 1;
+
+  int Res = 255;
+  if (std::unique_ptr<llvm::Module> Module = Act->takeModule())
+    Res = Execute(std::move(Module), envp);
+
+  // Shutdown.
+
+  llvm::llvm_shutdown();
+
+  return Res;
+}