//===- ExecutionDriver.cpp - Allow execution of LLVM program --------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains code used to execute the program utilizing one of the
// various ways of running LLVM bitcode.
//
//===----------------------------------------------------------------------===//
#include "BugDriver.h"
#include "ToolRunner.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/FileUtilities.h"
#include "llvm/Support/Program.h"
#include "llvm/Support/SystemUtils.h"
#include "llvm/Support/raw_ostream.h"
#include <fstream>
using namespace llvm;
namespace {
// OutputType - Allow the user to specify the way code should be run, to test
// for miscompilation.
//
enum OutputType {
AutoPick, RunLLI, RunJIT, RunLLC, RunLLCIA, LLC_Safe, CompileCustom, Custom
};
cl::opt<double>
AbsTolerance("abs-tolerance", cl::desc("Absolute error tolerated"),
cl::init(0.0));
cl::opt<double>
RelTolerance("rel-tolerance", cl::desc("Relative error tolerated"),
cl::init(0.0));
cl::opt<OutputType>
InterpreterSel(cl::desc("Specify the \"test\" i.e. suspect back-end:"),
cl::values(clEnumValN(AutoPick, "auto", "Use best guess"),
clEnumValN(RunLLI, "run-int",
"Execute with the interpreter"),
clEnumValN(RunJIT, "run-jit", "Execute with JIT"),
clEnumValN(RunLLC, "run-llc", "Compile with LLC"),
clEnumValN(RunLLCIA, "run-llc-ia",
"Compile with LLC with integrated assembler"),
clEnumValN(LLC_Safe, "llc-safe", "Use LLC for all"),
clEnumValN(CompileCustom, "compile-custom",
"Use -compile-command to define a command to "
"compile the bitcode. Useful to avoid linking."),
clEnumValN(Custom, "run-custom",
"Use -exec-command to define a command to execute "
"the bitcode. Useful for cross-compilation."),
clEnumValEnd),
cl::init(AutoPick));
cl::opt<OutputType>
SafeInterpreterSel(cl::desc("Specify \"safe\" i.e. known-good backend:"),
cl::values(clEnumValN(AutoPick, "safe-auto", "Use best guess"),
clEnumValN(RunLLC, "safe-run-llc", "Compile with LLC"),
clEnumValN(Custom, "safe-run-custom",
"Use -exec-command to define a command to execute "
"the bitcode. Useful for cross-compilation."),
clEnumValEnd),
cl::init(AutoPick));
cl::opt<std::string>
SafeInterpreterPath("safe-path",
cl::desc("Specify the path to the \"safe\" backend program"),
cl::init(""));
cl::opt<bool>
AppendProgramExitCode("append-exit-code",
cl::desc("Append the exit code to the output so it gets diff'd too"),
cl::init(false));
cl::opt<std::string>
InputFile("input", cl::init("/dev/null"),
cl::desc("Filename to pipe in as stdin (default: /dev/null)"));
cl::list<std::string>
AdditionalSOs("additional-so",
cl::desc("Additional shared objects to load "
"into executing programs"));
cl::list<std::string>
AdditionalLinkerArgs("Xlinker",
cl::desc("Additional arguments to pass to the linker"));
cl::opt<std::string>
CustomCompileCommand("compile-command", cl::init("llc"),
cl::desc("Command to compile the bitcode (use with -compile-custom) "
"(default: llc)"));
cl::opt<std::string>
CustomExecCommand("exec-command", cl::init("simulate"),
cl::desc("Command to execute the bitcode (use with -run-custom) "
"(default: simulate)"));
}
namespace llvm {
// Anything specified after the --args option are taken as arguments to the
// program being debugged.
cl::list<std::string>
InputArgv("args", cl::Positional, cl::desc("<program arguments>..."),
cl::ZeroOrMore, cl::PositionalEatsArgs);
cl::opt<std::string>
OutputPrefix("output-prefix", cl::init("bugpoint"),
cl::desc("Prefix to use for outputs (default: 'bugpoint')"));
}
namespace {
cl::list<std::string>
ToolArgv("tool-args", cl::Positional, cl::desc("<tool arguments>..."),
cl::ZeroOrMore, cl::PositionalEatsArgs);
cl::list<std::string>
SafeToolArgv("safe-tool-args", cl::Positional,
cl::desc("<safe-tool arguments>..."),
cl::ZeroOrMore, cl::PositionalEatsArgs);
cl::opt<std::string>
CCBinary("gcc", cl::init(""), cl::desc("The gcc binary to use."));
cl::list<std::string>
CCToolArgv("gcc-tool-args", cl::Positional,
cl::desc("<gcc-tool arguments>..."),
cl::ZeroOrMore, cl::PositionalEatsArgs);
}
//===----------------------------------------------------------------------===//
// BugDriver method implementation
//
/// initializeExecutionEnvironment - This method is used to set up the
/// environment for executing LLVM programs.
///
bool BugDriver::initializeExecutionEnvironment() {
outs() << "Initializing execution environment: ";
// Create an instance of the AbstractInterpreter interface as specified on
// the command line
SafeInterpreter = nullptr;
std::string Message;
if (CCBinary.empty()) {
if (sys::findProgramByName("clang"))
CCBinary = "clang";
else
CCBinary = "gcc";
}
switch (InterpreterSel) {
case AutoPick:
if (!Interpreter) {
InterpreterSel = RunJIT;
Interpreter = AbstractInterpreter::createJIT(getToolName(), Message,
&ToolArgv);
}
if (!Interpreter) {
InterpreterSel = RunLLC;
Interpreter = AbstractInterpreter::createLLC(getToolName(), Message,
CCBinary, &ToolArgv,
&CCToolArgv);
}
if (!Interpreter) {
InterpreterSel = RunLLI;
Interpreter = AbstractInterpreter::createLLI(getToolName(), Message,
&ToolArgv);
}
if (!Interpreter) {
InterpreterSel = AutoPick;
Message = "Sorry, I can't automatically select an interpreter!\n";
}
break;
case RunLLI:
Interpreter = AbstractInterpreter::createLLI(getToolName(), Message,
&ToolArgv);
break;
case RunLLC:
case RunLLCIA:
case LLC_Safe:
Interpreter = AbstractInterpreter::createLLC(getToolName(), Message,
CCBinary, &ToolArgv,
&CCToolArgv,
InterpreterSel == RunLLCIA);
break;
case RunJIT:
Interpreter = AbstractInterpreter::createJIT(getToolName(), Message,
&ToolArgv);
break;
case CompileCustom:
Interpreter =
AbstractInterpreter::createCustomCompiler(Message, CustomCompileCommand);
break;
case Custom:
Interpreter =
AbstractInterpreter::createCustomExecutor(Message, CustomExecCommand);
break;
}
if (!Interpreter)
errs() << Message;
else // Display informational messages on stdout instead of stderr
outs() << Message;
std::string Path = SafeInterpreterPath;
if (Path.empty())
Path = getToolName();
std::vector<std::string> SafeToolArgs = SafeToolArgv;
switch (SafeInterpreterSel) {
case AutoPick:
// In "llc-safe" mode, default to using LLC as the "safe" backend.
if (!SafeInterpreter &&
InterpreterSel == LLC_Safe) {
SafeInterpreterSel = RunLLC;
SafeToolArgs.push_back("--relocation-model=pic");
SafeInterpreter = AbstractInterpreter::createLLC(Path.c_str(), Message,
CCBinary,
&SafeToolArgs,
&CCToolArgv);
}
if (!SafeInterpreter &&
InterpreterSel != RunLLC &&
InterpreterSel != RunJIT) {
SafeInterpreterSel = RunLLC;
SafeToolArgs.push_back("--relocation-model=pic");
SafeInterpreter = AbstractInterpreter::createLLC(Path.c_str(), Message,
CCBinary,
&SafeToolArgs,
&CCToolArgv);
}
if (!SafeInterpreter) {
SafeInterpreterSel = AutoPick;
Message = "Sorry, I can't automatically select a safe interpreter!\n";
}
break;
case RunLLC:
case RunLLCIA:
SafeToolArgs.push_back("--relocation-model=pic");
SafeInterpreter = AbstractInterpreter::createLLC(Path.c_str(), Message,
CCBinary, &SafeToolArgs,
&CCToolArgv,
SafeInterpreterSel == RunLLCIA);
break;
case Custom:
SafeInterpreter =
AbstractInterpreter::createCustomExecutor(Message, CustomExecCommand);
break;
default:
Message = "Sorry, this back-end is not supported by bugpoint as the "
"\"safe\" backend right now!\n";
break;
}
if (!SafeInterpreter) { outs() << Message << "\nExiting.\n"; exit(1); }
cc = CC::create(Message, CCBinary, &CCToolArgv);
if (!cc) { outs() << Message << "\nExiting.\n"; exit(1); }
// If there was an error creating the selected interpreter, quit with error.
return Interpreter == nullptr;
}
/// compileProgram - Try to compile the specified module, returning false and
/// setting Error if an error occurs. This is used for code generation
/// crash testing.
///
void BugDriver::compileProgram(Module *M, std::string *Error) const {
// Emit the program to a bitcode file...
SmallString<128> BitcodeFile;
int BitcodeFD;
std::error_code EC = sys::fs::createUniqueFile(
OutputPrefix + "-test-program-%%%%%%%.bc", BitcodeFD, BitcodeFile);
if (EC) {
errs() << ToolName << ": Error making unique filename: " << EC.message()
<< "\n";
exit(1);
}
if (writeProgramToFile(BitcodeFile.str(), BitcodeFD, M)) {
errs() << ToolName << ": Error emitting bitcode to file '" << BitcodeFile
<< "'!\n";
exit(1);
}
// Remove the temporary bitcode file when we are done.
FileRemover BitcodeFileRemover(BitcodeFile.str(), !SaveTemps);
// Actually compile the program!
Interpreter->compileProgram(BitcodeFile.str(), Error, Timeout, MemoryLimit);
}
/// executeProgram - This method runs "Program", capturing the output of the
/// program to a file, returning the filename of the file. A recommended
/// filename may be optionally specified.
///
std::string BugDriver::executeProgram(const Module *Program,
std::string OutputFile,
std::string BitcodeFile,
const std::string &SharedObj,
AbstractInterpreter *AI,
std::string *Error) const {
if (!AI) AI = Interpreter;
assert(AI && "Interpreter should have been created already!");
bool CreatedBitcode = false;
if (BitcodeFile.empty()) {
// Emit the program to a bitcode file...
SmallString<128> UniqueFilename;
int UniqueFD;
std::error_code EC = sys::fs::createUniqueFile(
OutputPrefix + "-test-program-%%%%%%%.bc", UniqueFD, UniqueFilename);
if (EC) {
errs() << ToolName << ": Error making unique filename: "
<< EC.message() << "!\n";
exit(1);
}
BitcodeFile = UniqueFilename.str();
if (writeProgramToFile(BitcodeFile, UniqueFD, Program)) {
errs() << ToolName << ": Error emitting bitcode to file '"
<< BitcodeFile << "'!\n";
exit(1);
}
CreatedBitcode = true;
}
// Remove the temporary bitcode file when we are done.
std::string BitcodePath(BitcodeFile);
FileRemover BitcodeFileRemover(BitcodePath,
CreatedBitcode && !SaveTemps);
if (OutputFile.empty()) OutputFile = OutputPrefix + "-execution-output-%%%%%%%";
// Check to see if this is a valid output filename...
SmallString<128> UniqueFile;
std::error_code EC = sys::fs::createUniqueFile(OutputFile, UniqueFile);
if (EC) {
errs() << ToolName << ": Error making unique filename: "
<< EC.message() << "\n";
exit(1);
}
OutputFile = UniqueFile.str();
// Figure out which shared objects to run, if any.
std::vector<std::string> SharedObjs(AdditionalSOs);
if (!SharedObj.empty())
SharedObjs.push_back(SharedObj);
int RetVal = AI->ExecuteProgram(BitcodeFile, InputArgv, InputFile, OutputFile,
Error, AdditionalLinkerArgs, SharedObjs,
Timeout, MemoryLimit);
if (!Error->empty())
return OutputFile;
if (RetVal == -1) {
errs() << "<timeout>";
static bool FirstTimeout = true;
if (FirstTimeout) {
outs() << "\n"
"*** Program execution timed out! This mechanism is designed to handle\n"
" programs stuck in infinite loops gracefully. The -timeout option\n"
" can be used to change the timeout threshold or disable it completely\n"
" (with -timeout=0). This message is only displayed once.\n";
FirstTimeout = false;
}
}
if (AppendProgramExitCode) {
std::ofstream outFile(OutputFile.c_str(), std::ios_base::app);
outFile << "exit " << RetVal << '\n';
outFile.close();
}
// Return the filename we captured the output to.
return OutputFile;
}
/// executeProgramSafely - Used to create reference output with the "safe"
/// backend, if reference output is not provided.
///
std::string BugDriver::executeProgramSafely(const Module *Program,
std::string OutputFile,
std::string *Error) const {
return executeProgram(Program, OutputFile, "", "", SafeInterpreter, Error);
}
std::string BugDriver::compileSharedObject(const std::string &BitcodeFile,
std::string &Error) {
assert(Interpreter && "Interpreter should have been created already!");
std::string OutputFile;
// Using the known-good backend.
CC::FileType FT = SafeInterpreter->OutputCode(BitcodeFile, OutputFile,
Error);
if (!Error.empty())
return "";
std::string SharedObjectFile;
bool Failure = cc->MakeSharedObject(OutputFile, FT, SharedObjectFile,
AdditionalLinkerArgs, Error);
if (!Error.empty())
return "";
if (Failure)
exit(1);
// Remove the intermediate C file
sys::fs::remove(OutputFile);
return SharedObjectFile;
}
/// createReferenceFile - calls compileProgram and then records the output
/// into ReferenceOutputFile. Returns true if reference file created, false
/// otherwise. Note: initializeExecutionEnvironment should be called BEFORE
/// this function.
///
bool BugDriver::createReferenceFile(Module *M, const std::string &Filename) {
std::string Error;
compileProgram(Program, &Error);
if (!Error.empty())
return false;
ReferenceOutputFile = executeProgramSafely(Program, Filename, &Error);
if (!Error.empty()) {
errs() << Error;
if (Interpreter != SafeInterpreter) {
errs() << "*** There is a bug running the \"safe\" backend. Either"
<< " debug it (for example with the -run-jit bugpoint option,"
<< " if JIT is being used as the \"safe\" backend), or fix the"
<< " error some other way.\n";
}
return false;
}
outs() << "\nReference output is: " << ReferenceOutputFile << "\n\n";
return true;
}
/// diffProgram - This method executes the specified module and diffs the
/// output against the file specified by ReferenceOutputFile. If the output
/// is different, 1 is returned. If there is a problem with the code
/// generator (e.g., llc crashes), this will set ErrMsg.
///
bool BugDriver::diffProgram(const Module *Program,
const std::string &BitcodeFile,
const std::string &SharedObject,
bool RemoveBitcode,
std::string *ErrMsg) const {
// Execute the program, generating an output file...
std::string Output(
executeProgram(Program, "", BitcodeFile, SharedObject, nullptr, ErrMsg));
if (!ErrMsg->empty())
return false;
std::string Error;
bool FilesDifferent = false;
if (int Diff = DiffFilesWithTolerance(ReferenceOutputFile,
Output,
AbsTolerance, RelTolerance, &Error)) {
if (Diff == 2) {
errs() << "While diffing output: " << Error << '\n';
exit(1);
}
FilesDifferent = true;
}
else {
// Remove the generated output if there are no differences.
sys::fs::remove(Output);
}
// Remove the bitcode file if we are supposed to.
if (RemoveBitcode)
sys::fs::remove(BitcodeFile);
return FilesDifferent;
}
bool BugDriver::isExecutingJIT() {
return InterpreterSel == RunJIT;
}