freebsd-dev/contrib/llvm/tools/bugpoint/OptimizerDriver.cpp
2017-01-02 21:25:48 +00:00

287 lines
9.6 KiB
C++

//===- OptimizerDriver.cpp - Allow BugPoint to run passes safely ----------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines an interface that allows bugpoint to run various passes
// without the threat of a buggy pass corrupting bugpoint (of course, bugpoint
// may have its own bugs, but that's another story...). It achieves this by
// forking a copy of itself and having the child process do the optimizations.
// If this client dies, we can always fork a new one. :)
//
//===----------------------------------------------------------------------===//
#include "BugDriver.h"
#include "llvm/Bitcode/BitcodeWriter.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Verifier.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/FileUtilities.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/Program.h"
#include "llvm/Support/SystemUtils.h"
#include "llvm/Support/ToolOutputFile.h"
#define DONT_GET_PLUGIN_LOADER_OPTION
#include "llvm/Support/PluginLoader.h"
#include <fstream>
using namespace llvm;
#define DEBUG_TYPE "bugpoint"
namespace llvm {
extern cl::opt<std::string> OutputPrefix;
}
static cl::opt<bool> PreserveBitcodeUseListOrder(
"preserve-bc-uselistorder",
cl::desc("Preserve use-list order when writing LLVM bitcode."),
cl::init(true), cl::Hidden);
namespace {
// ChildOutput - This option captures the name of the child output file that
// is set up by the parent bugpoint process
cl::opt<std::string> ChildOutput("child-output", cl::ReallyHidden);
cl::opt<std::string> OptCmd("opt-command", cl::init(""),
cl::desc("Path to opt. (default: search path "
"for 'opt'.)"));
}
/// writeProgramToFile - This writes the current "Program" to the named bitcode
/// file. If an error occurs, true is returned.
///
static bool writeProgramToFileAux(tool_output_file &Out, const Module *M) {
WriteBitcodeToFile(M, Out.os(), PreserveBitcodeUseListOrder);
Out.os().close();
if (!Out.os().has_error()) {
Out.keep();
return false;
}
return true;
}
bool BugDriver::writeProgramToFile(const std::string &Filename, int FD,
const Module *M) const {
tool_output_file Out(Filename, FD);
return writeProgramToFileAux(Out, M);
}
bool BugDriver::writeProgramToFile(const std::string &Filename,
const Module *M) const {
std::error_code EC;
tool_output_file Out(Filename, EC, sys::fs::F_None);
if (!EC)
return writeProgramToFileAux(Out, M);
return true;
}
/// EmitProgressBitcode - This function is used to output the current Program
/// to a file named "bugpoint-ID.bc".
///
void BugDriver::EmitProgressBitcode(const Module *M, const std::string &ID,
bool NoFlyer) const {
// Output the input to the current pass to a bitcode file, emit a message
// telling the user how to reproduce it: opt -foo blah.bc
//
std::string Filename = OutputPrefix + "-" + ID + ".bc";
if (writeProgramToFile(Filename, M)) {
errs() << "Error opening file '" << Filename << "' for writing!\n";
return;
}
outs() << "Emitted bitcode to '" << Filename << "'\n";
if (NoFlyer || PassesToRun.empty())
return;
outs() << "\n*** You can reproduce the problem with: ";
if (UseValgrind)
outs() << "valgrind ";
outs() << "opt " << Filename;
for (unsigned i = 0, e = PluginLoader::getNumPlugins(); i != e; ++i) {
outs() << " -load " << PluginLoader::getPlugin(i);
}
outs() << " " << getPassesString(PassesToRun) << "\n";
}
cl::opt<bool> SilencePasses(
"silence-passes",
cl::desc("Suppress output of running passes (both stdout and stderr)"));
static cl::list<std::string> OptArgs("opt-args", cl::Positional,
cl::desc("<opt arguments>..."),
cl::ZeroOrMore, cl::PositionalEatsArgs);
/// runPasses - Run the specified passes on Program, outputting a bitcode file
/// and writing the filename into OutputFile if successful. If the
/// optimizations fail for some reason (optimizer crashes), return true,
/// otherwise return false. If DeleteOutput is set to true, the bitcode is
/// deleted on success, and the filename string is undefined. This prints to
/// outs() a single line message indicating whether compilation was successful
/// or failed.
///
bool BugDriver::runPasses(Module *Program,
const std::vector<std::string> &Passes,
std::string &OutputFilename, bool DeleteOutput,
bool Quiet, unsigned NumExtraArgs,
const char *const *ExtraArgs) const {
// setup the output file name
outs().flush();
SmallString<128> UniqueFilename;
std::error_code EC = sys::fs::createUniqueFile(
OutputPrefix + "-output-%%%%%%%.bc", UniqueFilename);
if (EC) {
errs() << getToolName()
<< ": Error making unique filename: " << EC.message() << "\n";
return 1;
}
OutputFilename = UniqueFilename.str();
// set up the input file name
SmallString<128> InputFilename;
int InputFD;
EC = sys::fs::createUniqueFile(OutputPrefix + "-input-%%%%%%%.bc", InputFD,
InputFilename);
if (EC) {
errs() << getToolName()
<< ": Error making unique filename: " << EC.message() << "\n";
return 1;
}
tool_output_file InFile(InputFilename, InputFD);
WriteBitcodeToFile(Program, InFile.os(), PreserveBitcodeUseListOrder);
InFile.os().close();
if (InFile.os().has_error()) {
errs() << "Error writing bitcode file: " << InputFilename << "\n";
InFile.os().clear_error();
return 1;
}
std::string tool = OptCmd;
if (OptCmd.empty()) {
if (ErrorOr<std::string> Path = sys::findProgramByName("opt"))
tool = *Path;
else
errs() << Path.getError().message() << "\n";
}
if (tool.empty()) {
errs() << "Cannot find `opt' in PATH!\n";
return 1;
}
std::string Prog;
if (UseValgrind) {
if (ErrorOr<std::string> Path = sys::findProgramByName("valgrind"))
Prog = *Path;
else
errs() << Path.getError().message() << "\n";
} else
Prog = tool;
if (Prog.empty()) {
errs() << "Cannot find `valgrind' in PATH!\n";
return 1;
}
// Ok, everything that could go wrong before running opt is done.
InFile.keep();
// setup the child process' arguments
SmallVector<const char *, 8> Args;
if (UseValgrind) {
Args.push_back("valgrind");
Args.push_back("--error-exitcode=1");
Args.push_back("-q");
Args.push_back(tool.c_str());
} else
Args.push_back(tool.c_str());
Args.push_back("-o");
Args.push_back(OutputFilename.c_str());
for (unsigned i = 0, e = OptArgs.size(); i != e; ++i)
Args.push_back(OptArgs[i].c_str());
std::vector<std::string> pass_args;
for (unsigned i = 0, e = PluginLoader::getNumPlugins(); i != e; ++i) {
pass_args.push_back(std::string("-load"));
pass_args.push_back(PluginLoader::getPlugin(i));
}
for (std::vector<std::string>::const_iterator I = Passes.begin(),
E = Passes.end();
I != E; ++I)
pass_args.push_back(std::string("-") + (*I));
for (std::vector<std::string>::const_iterator I = pass_args.begin(),
E = pass_args.end();
I != E; ++I)
Args.push_back(I->c_str());
Args.push_back(InputFilename.c_str());
for (unsigned i = 0; i < NumExtraArgs; ++i)
Args.push_back(*ExtraArgs);
Args.push_back(nullptr);
DEBUG(errs() << "\nAbout to run:\t";
for (unsigned i = 0, e = Args.size() - 1; i != e; ++i) errs()
<< " " << Args[i];
errs() << "\n";);
// Redirect stdout and stderr to nowhere if SilencePasses is given
StringRef Nowhere;
const StringRef *Redirects[3] = {nullptr, &Nowhere, &Nowhere};
std::string ErrMsg;
int result = sys::ExecuteAndWait(Prog, Args.data(), nullptr,
(SilencePasses ? Redirects : nullptr),
Timeout, MemoryLimit, &ErrMsg);
// If we are supposed to delete the bitcode file or if the passes crashed,
// remove it now. This may fail if the file was never created, but that's ok.
if (DeleteOutput || result != 0)
sys::fs::remove(OutputFilename);
// Remove the temporary input file as well
sys::fs::remove(InputFilename.c_str());
if (!Quiet) {
if (result == 0)
outs() << "Success!\n";
else if (result > 0)
outs() << "Exited with error code '" << result << "'\n";
else if (result < 0) {
if (result == -1)
outs() << "Execute failed: " << ErrMsg << "\n";
else
outs() << "Crashed: " << ErrMsg << "\n";
}
if (result & 0x01000000)
outs() << "Dumped core\n";
}
// Was the child successful?
return result != 0;
}
std::unique_ptr<Module>
BugDriver::runPassesOn(Module *M, const std::vector<std::string> &Passes,
unsigned NumExtraArgs, const char *const *ExtraArgs) {
std::string BitcodeResult;
if (runPasses(M, Passes, BitcodeResult, false /*delete*/, true /*quiet*/,
NumExtraArgs, ExtraArgs)) {
return nullptr;
}
std::unique_ptr<Module> Ret = parseInputFile(BitcodeResult, Context);
if (!Ret) {
errs() << getToolName() << ": Error reading bitcode file '" << BitcodeResult
<< "'!\n";
exit(1);
}
sys::fs::remove(BitcodeResult);
return Ret;
}