Add support for debugging miscompilations with the use of the JIT or …

…CBE!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@5990 91177308-0d34-0410-b5e6-96231b3b80d8

tools/bugpoint/ExecutionDriver.cpp

@@ -83,8 +83,10 @@ class LLI : public AbstractInterpreter {
 int LLI::ExecuteProgram(const std::string &Bytecode,
 			const std::string &OutputFile) {
   const char *Args[] = {
+    "lli",
     "-abort-on-exception",
     "-quiet",
+    "-force-interpreter=true",
     Bytecode.c_str(),
     0
   };
@@ -93,6 +95,159 @@ int LLI::ExecuteProgram(const std::string &Bytecode,
 			       InputFile, OutputFile, OutputFile);
 }
 
+//===----------------------------------------------------------------------===//
+// JIT Implementation of AbstractIntepreter interface
+//
+class JIT : public AbstractInterpreter {
+  std::string LLIPath;          // The path to the LLI executable
+public:
+  JIT(const std::string &Path) : LLIPath(Path) { }
+
+  // JIT create method - Try to find the LLI executable
+  static JIT *create(BugDriver *BD, std::string &Message) {
+    std::string LLIPath = FindExecutable("lli", BD->getToolName());
+    if (!LLIPath.empty()) {
+      Message = "Found lli: " + LLIPath + "\n";
+      return new JIT(LLIPath);
+    }
+
+    Message = "Cannot find 'lli' in bugpoint executable directory or PATH!\n";
+    return 0;
+  }
+  virtual int ExecuteProgram(const std::string &Bytecode,
+			     const std::string &OutputFile);
+};
+
+int JIT::ExecuteProgram(const std::string &Bytecode,
+			const std::string &OutputFile) {
+  const char *Args[] = {
+    "-lli",
+    "-quiet",
+    "-force-interpreter=false",
+    Bytecode.c_str(),
+    0
+  };
+
+  return RunProgramWithTimeout(LLIPath, Args,
+			       InputFile, OutputFile, OutputFile);
+}
+
+//===----------------------------------------------------------------------===//
+// CBE Implementation of AbstractIntepreter interface
+//
+class CBE : public AbstractInterpreter {
+  std::string DISPath;          // The path to the LLVM 'dis' executable
+  std::string GCCPath;          // The path to the gcc executable
+public:
+  CBE(const std::string &disPath, const std::string &gccPath)
+    : DISPath(disPath), GCCPath(gccPath) { }
+
+  // CBE create method - Try to find the 'dis' executable
+  static CBE *create(BugDriver *BD, std::string &Message) {
+    std::string DISPath = FindExecutable("dis", BD->getToolName());
+    if (DISPath.empty()) {
+      Message = "Cannot find 'dis' in bugpoint executable directory or PATH!\n";
+      return 0;
+    }
+
+    Message = "Found dis: " + DISPath + "\n";
+
+    std::string GCCPath = FindExecutable("gcc", BD->getToolName());
+    if (GCCPath.empty()) {
+      Message = "Cannot find 'gcc' in bugpoint executable directory or PATH!\n";
+      return 0;
+    }
+
+    Message += "Found gcc: " + GCCPath + "\n";
+    return new CBE(DISPath, GCCPath);
+  }
+  virtual int ExecuteProgram(const std::string &Bytecode,
+			     const std::string &OutputFile);
+};
+
+int CBE::ExecuteProgram(const std::string &Bytecode,
+			const std::string &OutputFile) {
+  std::string OutputCFile = getUniqueFilename("bugpoint.cbe.c");
+  const char *DisArgs[] = {
+    DISPath.c_str(),
+    "-o", OutputCFile.c_str(),   // Output to the C file
+    "-c",                        // Output to C
+    "-f",                        // Overwrite as necessary...
+    Bytecode.c_str(),            // This is the input bytecode
+    0
+  };
+
+  std::cout << "<cbe>";
+  if (RunProgramWithTimeout(DISPath, DisArgs, "/dev/null", "/dev/null",
+                            "/dev/null")) {                            
+    // If dis failed on the bytecode, print error...
+    std::cerr << "bugpoint error: dis -c failed!?\n";
+    removeFile(OutputCFile);
+    return 1;
+  }
+
+  // Assuming the c backend worked, compile the result with GCC...
+  std::string OutputBinary = getUniqueFilename("bugpoint.cbe.exe");
+  const char *GCCArgs[] = {
+    GCCPath.c_str(),
+    "-x", "c",                   // Force recognition as a C file
+    "-o", OutputBinary.c_str(),  // Output to the right filename...
+    OutputCFile.c_str(),         // Specify the input filename...
+    "-O2",                       // Optimize the program a bit...
+    0
+  };
+
+  // FIXME: Eventually the CC program and arguments for it should be settable on
+  // the bugpoint command line!
+
+  std::cout << "<gcc>";
+
+  // Run the C compiler on the output of the C backend...
+  if (RunProgramWithTimeout(GCCPath, GCCArgs, "/dev/null", "/dev/null",
+                            "/dev/null")) {
+    std::cerr << "\n*** bugpoint error: invocation of the C compiler "
+      "failed on CBE result!\n";
+    for (const char **Arg = DisArgs; *Arg; ++Arg)
+      std::cerr << " " << *Arg;
+    std::cerr << "\n";
+    for (const char **Arg = GCCArgs; *Arg; ++Arg)
+      std::cerr << " " << *Arg;
+    std::cerr << "\n";
+
+    // Rerun the compiler, capturing any error messages to print them.
+    std::string ErrorFilename = getUniqueFilename("bugpoint.cbe.errors");
+    RunProgramWithTimeout(GCCPath, GCCArgs, "/dev/null", ErrorFilename.c_str(),
+                          ErrorFilename.c_str());
+
+    // Read the error message into a string.
+    std::ifstream ErrorFile(ErrorFilename.c_str());
+    if (ErrorFile) {
+      std::copy(std::istreambuf_iterator<char>(ErrorFile),
+                std::istreambuf_iterator<char>(),
+                std::ostreambuf_iterator<char>(std::cerr));
+      ErrorFile.close();
+      std::cerr << "\n";      
+    }
+
+    removeFile(ErrorFilename);
+    exit(1);  // Leave stuff around for the user to inspect or debug the CBE
+  }
+
+  const char *ProgramArgs[] = {
+    OutputBinary.c_str(),
+    0
+  };
+
+  std::cout << "<program>";
+
+  // Now that we have a binary, run it!
+  int Result =  RunProgramWithTimeout(OutputBinary, ProgramArgs,
+                                      InputFile, OutputFile, OutputFile);
+  std::cout << " ";
+  removeFile(OutputCFile);
+  removeFile(OutputBinary);
+  return Result;
+}
 
 //===----------------------------------------------------------------------===//
 // BugDriver method implementation
@@ -110,10 +265,13 @@ bool BugDriver::initializeExecutionEnvironment() {
   // Create an instance of the AbstractInterpreter interface as specified on the
   // command line
   std::string Message;
-  if (InterpreterSel == RunLLI) {
-    Interpreter = LLI::create(this, Message);
-  } else {
-    Message = " Sorry, only LLI is supported right now!";
+  switch (InterpreterSel) {
+  case RunLLI: Interpreter = LLI::create(this, Message); break;
+  case RunJIT: Interpreter = JIT::create(this, Message); break;
+  case RunCBE: Interpreter = CBE::create(this, Message); break;
+  default:
+    Message = " Sorry, this back-end is not supported by bugpoint right now!\n";
+    break;
   }
 
   std::cout << Message;