llvm-6502/tools/bugpoint/OptimizerDriver.cpp
Chris Lattner 9686ae7f4e Teach bugpoint to kill optimization passes that run over the timeout limit,
which allows it to debug optimizer infinite loops.  This patch is contributed
by Nick Lewycky, thanks!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28763 91177308-0d34-0410-b5e6-96231b3b80d8
2006-06-13 03:10:48 +00:00

240 lines
8.4 KiB
C++

//===- OptimizerDriver.cpp - Allow BugPoint to run passes safely ----------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and 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. :)
//
//===----------------------------------------------------------------------===//
// Note: as a short term hack, the old Unix-specific code and platform-
// independent code co-exist via conditional compilation until it is verified
// that the new code works correctly on Unix.
#include "BugDriver.h"
#include "llvm/Module.h"
#include "llvm/PassManager.h"
#include "llvm/Analysis/Verifier.h"
#include "llvm/Bytecode/WriteBytecodePass.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Support/FileUtilities.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/System/Path.h"
#include "llvm/System/Program.h"
#include "llvm/Config/alloca.h"
#define DONT_GET_PLUGIN_LOADER_OPTION
#include "llvm/Support/PluginLoader.h"
#include <fstream>
using namespace llvm;
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);
}
/// writeProgramToFile - This writes the current "Program" to the named bytecode
/// file. If an error occurs, true is returned.
///
bool BugDriver::writeProgramToFile(const std::string &Filename,
Module *M) const {
std::ios::openmode io_mode = std::ios::out | std::ios::trunc |
std::ios::binary;
std::ofstream Out(Filename.c_str(), io_mode);
if (!Out.good()) return true;
try {
WriteBytecodeToFile(M ? M : Program, Out, /*compression=*/true);
} catch (...) {
return true;
}
return false;
}
/// EmitProgressBytecode - This function is used to output the current Program
/// to a file named "bugpoint-ID.bc".
///
void BugDriver::EmitProgressBytecode(const std::string &ID, bool NoFlyer) {
// Output the input to the current pass to a bytecode file, emit a message
// telling the user how to reproduce it: opt -foo blah.bc
//
std::string Filename = "bugpoint-" + ID + ".bc";
if (writeProgramToFile(Filename)) {
std::cerr << "Error opening file '" << Filename << "' for writing!\n";
return;
}
std::cout << "Emitted bytecode to '" << Filename << "'\n";
if (NoFlyer || PassesToRun.empty()) return;
std::cout << "\n*** You can reproduce the problem with: ";
unsigned PassType = PassesToRun[0]->getPassType();
for (unsigned i = 1, e = PassesToRun.size(); i != e; ++i)
PassType &= PassesToRun[i]->getPassType();
if (PassType & PassInfo::Analysis)
std::cout << "analyze";
else if (PassType & PassInfo::Optimization)
std::cout << "opt";
else
std::cout << "bugpoint";
std::cout << " " << Filename << " ";
std::cout << getPassesString(PassesToRun) << "\n";
}
int BugDriver::runPassesAsChild(const std::vector<const PassInfo*> &Passes) {
std::ios::openmode io_mode = std::ios::out | std::ios::trunc |
std::ios::binary;
std::ofstream OutFile(ChildOutput.c_str(), io_mode);
if (!OutFile.good()) {
std::cerr << "Error opening bytecode file: " << ChildOutput << "\n";
return 1;
}
PassManager PM;
// Make sure that the appropriate target data is always used...
PM.add(new TargetData("bugpoint", Program));
for (unsigned i = 0, e = Passes.size(); i != e; ++i) {
if (Passes[i]->getNormalCtor())
PM.add(Passes[i]->getNormalCtor()());
else
std::cerr << "Cannot create pass yet: " << Passes[i]->getPassName()
<< "\n";
}
// Check that the module is well formed on completion of optimization
PM.add(createVerifierPass());
// Write bytecode out to disk as the last step...
PM.add(new WriteBytecodePass(&OutFile));
// Run all queued passes.
PM.run(*Program);
return 0;
}
/// runPasses - Run the specified passes on Program, outputting a bytecode 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 bytecode is
/// deleted on success, and the filename string is undefined. This prints to
/// cout a single line message indicating whether compilation was successful or
/// failed.
///
bool BugDriver::runPasses(const std::vector<const PassInfo*> &Passes,
std::string &OutputFilename, bool DeleteOutput,
bool Quiet) const{
// setup the output file name
std::cout << std::flush;
sys::Path uniqueFilename("bugpoint-output.bc");
uniqueFilename.makeUnique();
OutputFilename = uniqueFilename.toString();
// set up the input file name
sys::Path inputFilename("bugpoint-input.bc");
inputFilename.makeUnique();
std::ios::openmode io_mode = std::ios::out | std::ios::trunc |
std::ios::binary;
std::ofstream InFile(inputFilename.c_str(), io_mode);
if (!InFile.good()) {
std::cerr << "Error opening bytecode file: " << inputFilename << "\n";
return(1);
}
WriteBytecodeToFile(Program,InFile,false);
InFile.close();
// setup the child process' arguments
const char** args = (const char**)
alloca(sizeof(const char*) *
(Passes.size()+10+2*PluginLoader::getNumPlugins()));
int n = 0;
args[n++] = ToolName.c_str();
args[n++] = "-as-child";
args[n++] = "-child-output";
args[n++] = OutputFilename.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<const PassInfo*>::const_iterator I = Passes.begin(),
E = Passes.end(); I != E; ++I )
pass_args.push_back( std::string("-") + (*I)->getPassArgument() );
for (std::vector<std::string>::const_iterator I = pass_args.begin(),
E = pass_args.end(); I != E; ++I )
args[n++] = I->c_str();
args[n++] = inputFilename.c_str();
args[n++] = 0;
sys::Path prog(sys::Program::FindProgramByName(ToolName));
int result = sys::Program::ExecuteAndWait(prog,args,0,0,Timeout);
// If we are supposed to delete the bytecode 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::Path(OutputFilename).eraseFromDisk();
// Remove the temporary input file as well
inputFilename.eraseFromDisk();
if (!Quiet) {
if (result == 0)
std::cout << "Success!\n";
else if (result > 0)
std::cout << "Exited with error code '" << result << "'\n";
else if (result < 0)
std::cout << "Crashed with signal #" << abs(result) << "\n";
if (result & 0x01000000)
std::cout << "Dumped core\n";
}
// Was the child successful?
return result != 0;
}
/// runPassesOn - Carefully run the specified set of pass on the specified
/// module, returning the transformed module on success, or a null pointer on
/// failure.
Module *BugDriver::runPassesOn(Module *M,
const std::vector<const PassInfo*> &Passes,
bool AutoDebugCrashes) {
Module *OldProgram = swapProgramIn(M);
std::string BytecodeResult;
if (runPasses(Passes, BytecodeResult, false/*delete*/, true/*quiet*/)) {
if (AutoDebugCrashes) {
std::cerr << " Error running this sequence of passes"
<< " on the input program!\n";
delete OldProgram;
EmitProgressBytecode("pass-error", false);
exit(debugOptimizerCrash());
}
swapProgramIn(OldProgram);
return 0;
}
// Restore the current program.
swapProgramIn(OldProgram);
Module *Ret = ParseInputFile(BytecodeResult);
if (Ret == 0) {
std::cerr << getToolName() << ": Error reading bytecode file '"
<< BytecodeResult << "'!\n";
exit(1);
}
sys::Path(BytecodeResult).eraseFromDisk(); // No longer need the file on disk
return Ret;
}