1 //===- OptimizerDriver.cpp - Allow BugPoint to run passes safely ----------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines an interface that allows bugpoint to run various passes
11 // without the threat of a buggy pass corrupting bugpoint (of course, bugpoint
12 // may have its own bugs, but that's another story...). It achieves this by
13 // forking a copy of itself and having the child process do the optimizations.
14 // If this client dies, we can always fork a new one. :)
16 //===----------------------------------------------------------------------===//
18 // Note: as a short term hack, the old Unix-specific code and platform-
19 // independent code co-exist via conditional compilation until it is verified
20 // that the new code works correctly on Unix.
23 #define PLATFORMINDEPENDENT
26 #include "BugDriver.h"
27 #include "llvm/Module.h"
28 #include "llvm/PassManager.h"
29 #include "llvm/Analysis/Verifier.h"
30 #include "llvm/Bytecode/WriteBytecodePass.h"
31 #include "llvm/Target/TargetData.h"
32 #include "llvm/Support/FileUtilities.h"
33 #include "llvm/System/Path.h"
35 #ifndef PLATFORMINDEPENDENT
37 #include <sys/types.h>
42 /// writeProgramToFile - This writes the current "Program" to the named bytecode
43 /// file. If an error occurs, true is returned.
45 bool BugDriver::writeProgramToFile(const std::string &Filename,
47 std::ios::openmode io_mode = std::ios::out | std::ios::trunc |
49 std::ofstream Out(Filename.c_str(), io_mode);
50 if (!Out.good()) return true;
51 WriteBytecodeToFile(M ? M : Program, Out, /*compression=*/true);
56 /// EmitProgressBytecode - This function is used to output the current Program
57 /// to a file named "bugpoint-ID.bc".
59 void BugDriver::EmitProgressBytecode(const std::string &ID, bool NoFlyer) {
60 // Output the input to the current pass to a bytecode file, emit a message
61 // telling the user how to reproduce it: opt -foo blah.bc
63 std::string Filename = "bugpoint-" + ID + ".bc";
64 if (writeProgramToFile(Filename)) {
65 std::cerr << "Error opening file '" << Filename << "' for writing!\n";
69 std::cout << "Emitted bytecode to '" << Filename << "'\n";
70 if (NoFlyer || PassesToRun.empty()) return;
71 std::cout << "\n*** You can reproduce the problem with: ";
73 unsigned PassType = PassesToRun[0]->getPassType();
74 for (unsigned i = 1, e = PassesToRun.size(); i != e; ++i)
75 PassType &= PassesToRun[i]->getPassType();
77 if (PassType & PassInfo::Analysis)
78 std::cout << "analyze";
79 else if (PassType & PassInfo::Optimization)
81 else if (PassType & PassInfo::LLC)
84 std::cout << "bugpoint";
85 std::cout << " " << Filename << " ";
86 std::cout << getPassesString(PassesToRun) << "\n";
89 static void RunChild(Module *Program,const std::vector<const PassInfo*> &Passes,
90 const std::string &OutFilename) {
91 std::ios::openmode io_mode = std::ios::out | std::ios::trunc |
93 std::ofstream OutFile(OutFilename.c_str(), io_mode);
94 if (!OutFile.good()) {
95 std::cerr << "Error opening bytecode file: " << OutFilename << "\n";
100 // Make sure that the appropriate target data is always used...
101 PM.add(new TargetData("bugpoint", Program));
103 for (unsigned i = 0, e = Passes.size(); i != e; ++i) {
104 if (Passes[i]->getNormalCtor())
105 PM.add(Passes[i]->getNormalCtor()());
107 std::cerr << "Cannot create pass yet: " << Passes[i]->getPassName()
110 // Check that the module is well formed on completion of optimization
111 PM.add(createVerifierPass());
113 // Write bytecode out to disk as the last step...
114 PM.add(new WriteBytecodePass(&OutFile));
116 // Run all queued passes.
120 /// runPasses - Run the specified passes on Program, outputting a bytecode file
121 /// and writing the filename into OutputFile if successful. If the
122 /// optimizations fail for some reason (optimizer crashes), return true,
123 /// otherwise return false. If DeleteOutput is set to true, the bytecode is
124 /// deleted on success, and the filename string is undefined. This prints to
125 /// cout a single line message indicating whether compilation was successful or
128 bool BugDriver::runPasses(const std::vector<const PassInfo*> &Passes,
129 std::string &OutputFilename, bool DeleteOutput,
131 std::cout << std::flush;
132 sys::Path uniqueFilename("bugpoint-output.bc");
133 uniqueFilename.makeUnique();
134 OutputFilename = uniqueFilename.toString();
136 #ifndef PLATFORMINDEPENDENT
138 switch (child_pid = fork()) {
139 case -1: // Error occurred
140 std::cerr << ToolName << ": Error forking!\n";
142 case 0: // Child process runs passes.
143 RunChild(Program, Passes, OutputFilename);
144 exit(0); // If we finish successfully, return 0!
145 default: // Parent continues...
149 // Wait for the child process to get done.
151 if (wait(&Status) != child_pid) {
152 std::cerr << "Error waiting for child process!\n";
156 bool ExitedOK = WIFEXITED(Status) && WEXITSTATUS(Status) == 0;
158 bool ExitedOK = false;
161 // If we are supposed to delete the bytecode file or if the passes crashed,
162 // remove it now. This may fail if the file was never created, but that's ok.
163 if (DeleteOutput || !ExitedOK)
164 sys::Path(OutputFilename).destroyFile();
166 #ifndef PLATFORMINDEPENDENT
169 std::cout << "Success!\n";
170 else if (WIFEXITED(Status))
171 std::cout << "Exited with error code '" << WEXITSTATUS(Status) << "'\n";
172 else if (WIFSIGNALED(Status))
173 std::cout << "Crashed with signal #" << WTERMSIG(Status) << "\n";
175 else if (WCOREDUMP(Status))
176 std::cout << "Dumped core\n";
179 std::cout << "Failed for unknown reason!\n";
183 // Was the child successful?
188 /// runPassesOn - Carefully run the specified set of pass on the specified
189 /// module, returning the transformed module on success, or a null pointer on
191 Module *BugDriver::runPassesOn(Module *M,
192 const std::vector<const PassInfo*> &Passes,
193 bool AutoDebugCrashes) {
194 Module *OldProgram = swapProgramIn(M);
195 std::string BytecodeResult;
196 if (runPasses(Passes, BytecodeResult, false/*delete*/, true/*quiet*/)) {
197 if (AutoDebugCrashes) {
198 std::cerr << " Error running this sequence of passes"
199 << " on the input program!\n";
201 EmitProgressBytecode("pass-error", false);
202 exit(debugOptimizerCrash());
204 swapProgramIn(OldProgram);
208 // Restore the current program.
209 swapProgramIn(OldProgram);
211 Module *Ret = ParseInputFile(BytecodeResult);
213 std::cerr << getToolName() << ": Error reading bytecode file '"
214 << BytecodeResult << "'!\n";
217 sys::Path(BytecodeResult).destroyFile(); // No longer need the file on disk