From 7c863eb8cc34c8ae97ae90672758eb6637b1125f Mon Sep 17 00:00:00 2001 From: Andrew Trick Date: Wed, 11 May 2011 16:31:24 +0000 Subject: Bugpoint support for miscompilations that result in a crash. This change allows bugpoint to pinpoint the "opt" pass and bitcode segment responsible for a crash caused by miscompilation. At least it works well for me now, without having to create any custom execution wrappers. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131186 91177308-0d34-0410-b5e6-96231b3b80d8 --- include/llvm/Support/Program.h | 7 +++++-- lib/Support/Program.cpp | 5 +++-- lib/Support/Unix/Program.inc | 7 +++++-- tools/bugpoint/ExecutionDriver.cpp | 2 +- tools/bugpoint/Miscompilation.cpp | 5 +++-- tools/bugpoint/ToolRunner.cpp | 18 ++++++++++++++++-- 6 files changed, 33 insertions(+), 11 deletions(-) diff --git a/include/llvm/Support/Program.h b/include/llvm/Support/Program.h index 96b3566..986c53e 100644 --- a/include/llvm/Support/Program.h +++ b/include/llvm/Support/Program.h @@ -96,9 +96,11 @@ namespace sys { ///< expires, the child is killed and this call returns. If zero, ///< this function will wait until the child finishes or forever if ///< it doesn't. - std::string* ErrMsg ///< If non-zero, provides a pointer to a string + std::string* ErrMsg, ///< If non-zero, provides a pointer to a string ///< instance in which error messages will be returned. If the string ///< is non-empty upon return an error occurred while waiting. + const char *SignalPrefix ///< If non-zero, provides a prefix to be + ///< prepended to ErrMsg if the process is terminated abnormally. ); /// This function terminates the program. @@ -137,7 +139,8 @@ namespace sys { const sys::Path** redirects = 0, unsigned secondsToWait = 0, unsigned memoryLimit = 0, - std::string* ErrMsg = 0); + std::string* ErrMsg = 0, + const char *SignalPrefix = 0); /// A convenience function equivalent to Program prg; prg.Execute(..); /// @see Execute diff --git a/lib/Support/Program.cpp b/lib/Support/Program.cpp index 01860b0..fa816f6 100644 --- a/lib/Support/Program.cpp +++ b/lib/Support/Program.cpp @@ -28,10 +28,11 @@ Program::ExecuteAndWait(const Path& path, const Path** redirects, unsigned secondsToWait, unsigned memoryLimit, - std::string* ErrMsg) { + std::string* ErrMsg, + const char* SignalPrefix) { Program prg; if (prg.Execute(path, args, envp, redirects, memoryLimit, ErrMsg)) - return prg.Wait(path, secondsToWait, ErrMsg); + return prg.Wait(path, secondsToWait, ErrMsg, SignalPrefix); else return -1; } diff --git a/lib/Support/Unix/Program.inc b/lib/Support/Unix/Program.inc index 9f0a9ef..86f3aa9 100644 --- a/lib/Support/Unix/Program.inc +++ b/lib/Support/Unix/Program.inc @@ -298,7 +298,8 @@ Program::Execute(const Path &path, const char **args, const char **envp, int Program::Wait(const sys::Path &path, unsigned secondsToWait, - std::string* ErrMsg) + std::string* ErrMsg, + const char* SignalPrefix) { #ifdef HAVE_SYS_WAIT_H struct sigaction Act, Old; @@ -376,7 +377,9 @@ Program::Wait(const sys::Path &path, } } else if (WIFSIGNALED(status)) { if (ErrMsg) { - *ErrMsg = strsignal(WTERMSIG(status)); + if (SignalPrefix) + *ErrMsg = SignalPrefix; + *ErrMsg += strsignal(WTERMSIG(status)); #ifdef WCOREDUMP if (WCOREDUMP(status)) *ErrMsg += " (core dumped)"; diff --git a/tools/bugpoint/ExecutionDriver.cpp b/tools/bugpoint/ExecutionDriver.cpp index 9be9dfd..77c01ac 100644 --- a/tools/bugpoint/ExecutionDriver.cpp +++ b/tools/bugpoint/ExecutionDriver.cpp @@ -475,7 +475,7 @@ bool BugDriver::createReferenceFile(Module *M, const std::string &Filename) { /// 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 return -1 and set Error. +/// generator (e.g., llc crashes), this will set ErrMsg. /// bool BugDriver::diffProgram(const Module *Program, const std::string &BitcodeFile, diff --git a/tools/bugpoint/Miscompilation.cpp b/tools/bugpoint/Miscompilation.cpp index a9db38f..1834fe1 100644 --- a/tools/bugpoint/Miscompilation.cpp +++ b/tools/bugpoint/Miscompilation.cpp @@ -624,9 +624,10 @@ DebugAMiscompilation(BugDriver &BD, if (!BugpointIsInterrupted) ReduceMiscompilingFunctions(BD, TestFn).reduceList(MiscompiledFunctions, Error); - if (!Error.empty()) + if (!Error.empty()) { + errs() << "\n***Cannot reduce functions: "; return MiscompiledFunctions; - + } outs() << "\n*** The following function" << (MiscompiledFunctions.size() == 1 ? " is" : "s are") << " being miscompiled: "; diff --git a/tools/bugpoint/ToolRunner.cpp b/tools/bugpoint/ToolRunner.cpp index 6c46ef1..9c3e612 100644 --- a/tools/bugpoint/ToolRunner.cpp +++ b/tools/bugpoint/ToolRunner.cpp @@ -50,6 +50,11 @@ namespace { cl::desc("Remote execution (rsh/ssh) extra options")); } +// Add a prefix to ErrMsg if the program is terminated by a signal to +// distinguish compiled program crashes from other execution +// failures. Miscompilation likely to results in SIGSEGV. +static const char *SignalPrefix = "Signal - "; + /// RunProgramWithTimeout - This function provides an alternate interface /// to the sys::Program::ExecuteAndWait interface. /// @see sys::Program::ExecuteAndWait @@ -77,7 +82,7 @@ static int RunProgramWithTimeout(const sys::Path &ProgramPath, return sys::Program::ExecuteAndWait(ProgramPath, Args, 0, redirects, - NumSeconds, MemoryLimit, ErrMsg); + NumSeconds, MemoryLimit, ErrMsg, SignalPrefix); } /// RunProgramRemotelyWithTimeout - This function runs the given program @@ -854,9 +859,18 @@ int GCC::ExecuteProgram(const std::string &ProgramFile, if (RemoteClientPath.isEmpty()) { DEBUG(errs() << ""); - return RunProgramWithTimeout(OutputBinary, &ProgramArgs[0], + int ExitCode = RunProgramWithTimeout(OutputBinary, &ProgramArgs[0], sys::Path(InputFile), sys::Path(OutputFile), sys::Path(OutputFile), Timeout, MemoryLimit, Error); + // Treat a signal (usually SIGSEGV) as part of the program output so that + // crash-causing miscompilation is handled seamlessly. + if (Error->find(SignalPrefix) == 0) { + std::ofstream outFile(OutputFile.c_str(), std::ios_base::app); + outFile << *Error << '\n'; + outFile.close(); + Error->clear(); + } + return ExitCode; } else { outs() << ""; outs().flush(); return RunProgramRemotelyWithTimeout(sys::Path(RemoteClientPath), -- cgit v1.1