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Diffstat (limited to 'contrib/llvm/tools/bugpoint/Miscompilation.cpp')
| -rw-r--r-- | contrib/llvm/tools/bugpoint/Miscompilation.cpp | 1082 |
1 files changed, 0 insertions, 1082 deletions
diff --git a/contrib/llvm/tools/bugpoint/Miscompilation.cpp b/contrib/llvm/tools/bugpoint/Miscompilation.cpp deleted file mode 100644 index 3f2b696..0000000 --- a/contrib/llvm/tools/bugpoint/Miscompilation.cpp +++ /dev/null @@ -1,1082 +0,0 @@ -//===- Miscompilation.cpp - Debug program miscompilations -----------------===// -// -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This file implements optimizer and code generation miscompilation debugging -// support. -// -//===----------------------------------------------------------------------===// - -#include "BugDriver.h" -#include "ListReducer.h" -#include "ToolRunner.h" -#include "llvm/Constants.h" -#include "llvm/DerivedTypes.h" -#include "llvm/Instructions.h" -#include "llvm/Linker.h" -#include "llvm/Module.h" -#include "llvm/Pass.h" -#include "llvm/Analysis/Verifier.h" -#include "llvm/Transforms/Utils/Cloning.h" -#include "llvm/Support/CommandLine.h" -#include "llvm/Support/FileUtilities.h" -#include "llvm/Config/config.h" // for HAVE_LINK_R -using namespace llvm; - -namespace llvm { - extern cl::opt<std::string> OutputPrefix; - extern cl::list<std::string> InputArgv; -} - -namespace { - static llvm::cl::opt<bool> - DisableLoopExtraction("disable-loop-extraction", - cl::desc("Don't extract loops when searching for miscompilations"), - cl::init(false)); - static llvm::cl::opt<bool> - DisableBlockExtraction("disable-block-extraction", - cl::desc("Don't extract blocks when searching for miscompilations"), - cl::init(false)); - - class ReduceMiscompilingPasses : public ListReducer<std::string> { - BugDriver &BD; - public: - ReduceMiscompilingPasses(BugDriver &bd) : BD(bd) {} - - virtual TestResult doTest(std::vector<std::string> &Prefix, - std::vector<std::string> &Suffix, - std::string &Error); - }; -} - -/// TestResult - After passes have been split into a test group and a control -/// group, see if they still break the program. -/// -ReduceMiscompilingPasses::TestResult -ReduceMiscompilingPasses::doTest(std::vector<std::string> &Prefix, - std::vector<std::string> &Suffix, - std::string &Error) { - // First, run the program with just the Suffix passes. If it is still broken - // with JUST the kept passes, discard the prefix passes. - outs() << "Checking to see if '" << getPassesString(Suffix) - << "' compiles correctly: "; - - std::string BitcodeResult; - if (BD.runPasses(BD.getProgram(), Suffix, BitcodeResult, false/*delete*/, - true/*quiet*/)) { - errs() << " Error running this sequence of passes" - << " on the input program!\n"; - BD.setPassesToRun(Suffix); - BD.EmitProgressBitcode(BD.getProgram(), "pass-error", false); - exit(BD.debugOptimizerCrash()); - } - - // Check to see if the finished program matches the reference output... - bool Diff = BD.diffProgram(BD.getProgram(), BitcodeResult, "", - true /*delete bitcode*/, &Error); - if (!Error.empty()) - return InternalError; - if (Diff) { - outs() << " nope.\n"; - if (Suffix.empty()) { - errs() << BD.getToolName() << ": I'm confused: the test fails when " - << "no passes are run, nondeterministic program?\n"; - exit(1); - } - return KeepSuffix; // Miscompilation detected! - } - outs() << " yup.\n"; // No miscompilation! - - if (Prefix.empty()) return NoFailure; - - // Next, see if the program is broken if we run the "prefix" passes first, - // then separately run the "kept" passes. - outs() << "Checking to see if '" << getPassesString(Prefix) - << "' compiles correctly: "; - - // If it is not broken with the kept passes, it's possible that the prefix - // passes must be run before the kept passes to break it. If the program - // WORKS after the prefix passes, but then fails if running the prefix AND - // kept passes, we can update our bitcode file to include the result of the - // prefix passes, then discard the prefix passes. - // - if (BD.runPasses(BD.getProgram(), Prefix, BitcodeResult, false/*delete*/, - true/*quiet*/)) { - errs() << " Error running this sequence of passes" - << " on the input program!\n"; - BD.setPassesToRun(Prefix); - BD.EmitProgressBitcode(BD.getProgram(), "pass-error", false); - exit(BD.debugOptimizerCrash()); - } - - // If the prefix maintains the predicate by itself, only keep the prefix! - Diff = BD.diffProgram(BD.getProgram(), BitcodeResult, "", false, &Error); - if (!Error.empty()) - return InternalError; - if (Diff) { - outs() << " nope.\n"; - sys::Path(BitcodeResult).eraseFromDisk(); - return KeepPrefix; - } - outs() << " yup.\n"; // No miscompilation! - - // Ok, so now we know that the prefix passes work, try running the suffix - // passes on the result of the prefix passes. - // - OwningPtr<Module> PrefixOutput(ParseInputFile(BitcodeResult, - BD.getContext())); - if (PrefixOutput == 0) { - errs() << BD.getToolName() << ": Error reading bitcode file '" - << BitcodeResult << "'!\n"; - exit(1); - } - sys::Path(BitcodeResult).eraseFromDisk(); // No longer need the file on disk - - // Don't check if there are no passes in the suffix. - if (Suffix.empty()) - return NoFailure; - - outs() << "Checking to see if '" << getPassesString(Suffix) - << "' passes compile correctly after the '" - << getPassesString(Prefix) << "' passes: "; - - OwningPtr<Module> OriginalInput(BD.swapProgramIn(PrefixOutput.take())); - if (BD.runPasses(BD.getProgram(), Suffix, BitcodeResult, false/*delete*/, - true/*quiet*/)) { - errs() << " Error running this sequence of passes" - << " on the input program!\n"; - BD.setPassesToRun(Suffix); - BD.EmitProgressBitcode(BD.getProgram(), "pass-error", false); - exit(BD.debugOptimizerCrash()); - } - - // Run the result... - Diff = BD.diffProgram(BD.getProgram(), BitcodeResult, "", - true /*delete bitcode*/, &Error); - if (!Error.empty()) - return InternalError; - if (Diff) { - outs() << " nope.\n"; - return KeepSuffix; - } - - // Otherwise, we must not be running the bad pass anymore. - outs() << " yup.\n"; // No miscompilation! - // Restore orig program & free test. - delete BD.swapProgramIn(OriginalInput.take()); - return NoFailure; -} - -namespace { - class ReduceMiscompilingFunctions : public ListReducer<Function*> { - BugDriver &BD; - bool (*TestFn)(BugDriver &, Module *, Module *, std::string &); - public: - ReduceMiscompilingFunctions(BugDriver &bd, - bool (*F)(BugDriver &, Module *, Module *, - std::string &)) - : BD(bd), TestFn(F) {} - - virtual TestResult doTest(std::vector<Function*> &Prefix, - std::vector<Function*> &Suffix, - std::string &Error) { - if (!Suffix.empty()) { - bool Ret = TestFuncs(Suffix, Error); - if (!Error.empty()) - return InternalError; - if (Ret) - return KeepSuffix; - } - if (!Prefix.empty()) { - bool Ret = TestFuncs(Prefix, Error); - if (!Error.empty()) - return InternalError; - if (Ret) - return KeepPrefix; - } - return NoFailure; - } - - bool TestFuncs(const std::vector<Function*> &Prefix, std::string &Error); - }; -} - -/// TestMergedProgram - Given two modules, link them together and run the -/// program, checking to see if the program matches the diff. If there is -/// an error, return NULL. If not, return the merged module. The Broken argument -/// will be set to true if the output is different. If the DeleteInputs -/// argument is set to true then this function deletes both input -/// modules before it returns. -/// -static Module *TestMergedProgram(const BugDriver &BD, Module *M1, Module *M2, - bool DeleteInputs, std::string &Error, - bool &Broken) { - // Link the two portions of the program back to together. - std::string ErrorMsg; - if (!DeleteInputs) { - M1 = CloneModule(M1); - M2 = CloneModule(M2); - } - if (Linker::LinkModules(M1, M2, &ErrorMsg)) { - errs() << BD.getToolName() << ": Error linking modules together:" - << ErrorMsg << '\n'; - exit(1); - } - delete M2; // We are done with this module. - - // Execute the program. - Broken = BD.diffProgram(M1, "", "", false, &Error); - if (!Error.empty()) { - // Delete the linked module - delete M1; - return NULL; - } - return M1; -} - -/// TestFuncs - split functions in a Module into two groups: those that are -/// under consideration for miscompilation vs. those that are not, and test -/// accordingly. Each group of functions becomes a separate Module. -/// -bool ReduceMiscompilingFunctions::TestFuncs(const std::vector<Function*> &Funcs, - std::string &Error) { - // Test to see if the function is misoptimized if we ONLY run it on the - // functions listed in Funcs. - outs() << "Checking to see if the program is misoptimized when " - << (Funcs.size()==1 ? "this function is" : "these functions are") - << " run through the pass" - << (BD.getPassesToRun().size() == 1 ? "" : "es") << ":"; - PrintFunctionList(Funcs); - outs() << '\n'; - - // Create a clone for two reasons: - // * If the optimization passes delete any function, the deleted function - // will be in the clone and Funcs will still point to valid memory - // * If the optimization passes use interprocedural information to break - // a function, we want to continue with the original function. Otherwise - // we can conclude that a function triggers the bug when in fact one - // needs a larger set of original functions to do so. - ValueMap<const Value*, Value*> VMap; - Module *Clone = CloneModule(BD.getProgram(), VMap); - Module *Orig = BD.swapProgramIn(Clone); - - std::vector<Function*> FuncsOnClone; - for (unsigned i = 0, e = Funcs.size(); i != e; ++i) { - Function *F = cast<Function>(VMap[Funcs[i]]); - FuncsOnClone.push_back(F); - } - - // Split the module into the two halves of the program we want. - VMap.clear(); - Module *ToNotOptimize = CloneModule(BD.getProgram(), VMap); - Module *ToOptimize = SplitFunctionsOutOfModule(ToNotOptimize, FuncsOnClone, - VMap); - - // Run the predicate, note that the predicate will delete both input modules. - bool Broken = TestFn(BD, ToOptimize, ToNotOptimize, Error); - - delete BD.swapProgramIn(Orig); - - return Broken; -} - -/// DisambiguateGlobalSymbols - Give anonymous global values names. -/// -static void DisambiguateGlobalSymbols(Module *M) { - for (Module::global_iterator I = M->global_begin(), E = M->global_end(); - I != E; ++I) - if (!I->hasName()) - I->setName("anon_global"); - for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I) - if (!I->hasName()) - I->setName("anon_fn"); -} - -/// ExtractLoops - Given a reduced list of functions that still exposed the bug, -/// check to see if we can extract the loops in the region without obscuring the -/// bug. If so, it reduces the amount of code identified. -/// -static bool ExtractLoops(BugDriver &BD, - bool (*TestFn)(BugDriver &, Module *, Module *, - std::string &), - std::vector<Function*> &MiscompiledFunctions, - std::string &Error) { - bool MadeChange = false; - while (1) { - if (BugpointIsInterrupted) return MadeChange; - - ValueMap<const Value*, Value*> VMap; - Module *ToNotOptimize = CloneModule(BD.getProgram(), VMap); - Module *ToOptimize = SplitFunctionsOutOfModule(ToNotOptimize, - MiscompiledFunctions, - VMap); - Module *ToOptimizeLoopExtracted = BD.ExtractLoop(ToOptimize); - if (!ToOptimizeLoopExtracted) { - // If the loop extractor crashed or if there were no extractible loops, - // then this chapter of our odyssey is over with. - delete ToNotOptimize; - delete ToOptimize; - return MadeChange; - } - - errs() << "Extracted a loop from the breaking portion of the program.\n"; - - // Bugpoint is intentionally not very trusting of LLVM transformations. In - // particular, we're not going to assume that the loop extractor works, so - // we're going to test the newly loop extracted program to make sure nothing - // has broken. If something broke, then we'll inform the user and stop - // extraction. - AbstractInterpreter *AI = BD.switchToSafeInterpreter(); - bool Failure; - Module *New = TestMergedProgram(BD, ToOptimizeLoopExtracted, ToNotOptimize, - false, Error, Failure); - if (!New) - return false; - // Delete the original and set the new program. - delete BD.swapProgramIn(New); - if (Failure) { - BD.switchToInterpreter(AI); - - // Merged program doesn't work anymore! - errs() << " *** ERROR: Loop extraction broke the program. :(" - << " Please report a bug!\n"; - errs() << " Continuing on with un-loop-extracted version.\n"; - - BD.writeProgramToFile(OutputPrefix + "-loop-extract-fail-tno.bc", - ToNotOptimize); - BD.writeProgramToFile(OutputPrefix + "-loop-extract-fail-to.bc", - ToOptimize); - BD.writeProgramToFile(OutputPrefix + "-loop-extract-fail-to-le.bc", - ToOptimizeLoopExtracted); - - errs() << "Please submit the " - << OutputPrefix << "-loop-extract-fail-*.bc files.\n"; - delete ToOptimize; - delete ToNotOptimize; - delete ToOptimizeLoopExtracted; - return MadeChange; - } - delete ToOptimize; - BD.switchToInterpreter(AI); - - outs() << " Testing after loop extraction:\n"; - // Clone modules, the tester function will free them. - Module *TOLEBackup = CloneModule(ToOptimizeLoopExtracted); - Module *TNOBackup = CloneModule(ToNotOptimize); - Failure = TestFn(BD, ToOptimizeLoopExtracted, ToNotOptimize, Error); - if (!Error.empty()) - return false; - if (!Failure) { - outs() << "*** Loop extraction masked the problem. Undoing.\n"; - // If the program is not still broken, then loop extraction did something - // that masked the error. Stop loop extraction now. - delete TOLEBackup; - delete TNOBackup; - return MadeChange; - } - ToOptimizeLoopExtracted = TOLEBackup; - ToNotOptimize = TNOBackup; - - outs() << "*** Loop extraction successful!\n"; - - std::vector<std::pair<std::string, const FunctionType*> > MisCompFunctions; - for (Module::iterator I = ToOptimizeLoopExtracted->begin(), - E = ToOptimizeLoopExtracted->end(); I != E; ++I) - if (!I->isDeclaration()) - MisCompFunctions.push_back(std::make_pair(I->getName(), - I->getFunctionType())); - - // Okay, great! Now we know that we extracted a loop and that loop - // extraction both didn't break the program, and didn't mask the problem. - // Replace the current program with the loop extracted version, and try to - // extract another loop. - std::string ErrorMsg; - if (Linker::LinkModules(ToNotOptimize, ToOptimizeLoopExtracted, &ErrorMsg)){ - errs() << BD.getToolName() << ": Error linking modules together:" - << ErrorMsg << '\n'; - exit(1); - } - delete ToOptimizeLoopExtracted; - - // All of the Function*'s in the MiscompiledFunctions list are in the old - // module. Update this list to include all of the functions in the - // optimized and loop extracted module. - MiscompiledFunctions.clear(); - for (unsigned i = 0, e = MisCompFunctions.size(); i != e; ++i) { - Function *NewF = ToNotOptimize->getFunction(MisCompFunctions[i].first); - - assert(NewF && "Function not found??"); - assert(NewF->getFunctionType() == MisCompFunctions[i].second && - "found wrong function type?"); - MiscompiledFunctions.push_back(NewF); - } - - BD.setNewProgram(ToNotOptimize); - MadeChange = true; - } -} - -namespace { - class ReduceMiscompiledBlocks : public ListReducer<BasicBlock*> { - BugDriver &BD; - bool (*TestFn)(BugDriver &, Module *, Module *, std::string &); - std::vector<Function*> FunctionsBeingTested; - public: - ReduceMiscompiledBlocks(BugDriver &bd, - bool (*F)(BugDriver &, Module *, Module *, - std::string &), - const std::vector<Function*> &Fns) - : BD(bd), TestFn(F), FunctionsBeingTested(Fns) {} - - virtual TestResult doTest(std::vector<BasicBlock*> &Prefix, - std::vector<BasicBlock*> &Suffix, - std::string &Error) { - if (!Suffix.empty()) { - bool Ret = TestFuncs(Suffix, Error); - if (!Error.empty()) - return InternalError; - if (Ret) - return KeepSuffix; - } - if (!Prefix.empty()) { - bool Ret = TestFuncs(Prefix, Error); - if (!Error.empty()) - return InternalError; - if (Ret) - return KeepPrefix; - } - return NoFailure; - } - - bool TestFuncs(const std::vector<BasicBlock*> &BBs, std::string &Error); - }; -} - -/// TestFuncs - Extract all blocks for the miscompiled functions except for the -/// specified blocks. If the problem still exists, return true. -/// -bool ReduceMiscompiledBlocks::TestFuncs(const std::vector<BasicBlock*> &BBs, - std::string &Error) { - // Test to see if the function is misoptimized if we ONLY run it on the - // functions listed in Funcs. - outs() << "Checking to see if the program is misoptimized when all "; - if (!BBs.empty()) { - outs() << "but these " << BBs.size() << " blocks are extracted: "; - for (unsigned i = 0, e = BBs.size() < 10 ? BBs.size() : 10; i != e; ++i) - outs() << BBs[i]->getName() << " "; - if (BBs.size() > 10) outs() << "..."; - } else { - outs() << "blocks are extracted."; - } - outs() << '\n'; - - // Split the module into the two halves of the program we want. - ValueMap<const Value*, Value*> VMap; - Module *Clone = CloneModule(BD.getProgram(), VMap); - Module *Orig = BD.swapProgramIn(Clone); - std::vector<Function*> FuncsOnClone; - std::vector<BasicBlock*> BBsOnClone; - for (unsigned i = 0, e = FunctionsBeingTested.size(); i != e; ++i) { - Function *F = cast<Function>(VMap[FunctionsBeingTested[i]]); - FuncsOnClone.push_back(F); - } - for (unsigned i = 0, e = BBs.size(); i != e; ++i) { - BasicBlock *BB = cast<BasicBlock>(VMap[BBs[i]]); - BBsOnClone.push_back(BB); - } - VMap.clear(); - - Module *ToNotOptimize = CloneModule(BD.getProgram(), VMap); - Module *ToOptimize = SplitFunctionsOutOfModule(ToNotOptimize, - FuncsOnClone, - VMap); - - // Try the extraction. If it doesn't work, then the block extractor crashed - // or something, in which case bugpoint can't chase down this possibility. - if (Module *New = BD.ExtractMappedBlocksFromModule(BBsOnClone, ToOptimize)) { - delete ToOptimize; - // Run the predicate, - // note that the predicate will delete both input modules. - bool Ret = TestFn(BD, New, ToNotOptimize, Error); - delete BD.swapProgramIn(Orig); - return Ret; - } - delete BD.swapProgramIn(Orig); - delete ToOptimize; - delete ToNotOptimize; - return false; -} - - -/// ExtractBlocks - Given a reduced list of functions that still expose the bug, -/// extract as many basic blocks from the region as possible without obscuring -/// the bug. -/// -static bool ExtractBlocks(BugDriver &BD, - bool (*TestFn)(BugDriver &, Module *, Module *, - std::string &), - std::vector<Function*> &MiscompiledFunctions, - std::string &Error) { - if (BugpointIsInterrupted) return false; - - std::vector<BasicBlock*> Blocks; - for (unsigned i = 0, e = MiscompiledFunctions.size(); i != e; ++i) - for (Function::iterator I = MiscompiledFunctions[i]->begin(), - E = MiscompiledFunctions[i]->end(); I != E; ++I) - Blocks.push_back(I); - - // Use the list reducer to identify blocks that can be extracted without - // obscuring the bug. The Blocks list will end up containing blocks that must - // be retained from the original program. - unsigned OldSize = Blocks.size(); - - // Check to see if all blocks are extractible first. - bool Ret = ReduceMiscompiledBlocks(BD, TestFn, MiscompiledFunctions) - .TestFuncs(std::vector<BasicBlock*>(), Error); - if (!Error.empty()) - return false; - if (Ret) { - Blocks.clear(); - } else { - ReduceMiscompiledBlocks(BD, TestFn, - MiscompiledFunctions).reduceList(Blocks, Error); - if (!Error.empty()) - return false; - if (Blocks.size() == OldSize) - return false; - } - - ValueMap<const Value*, Value*> VMap; - Module *ProgClone = CloneModule(BD.getProgram(), VMap); - Module *ToExtract = SplitFunctionsOutOfModule(ProgClone, - MiscompiledFunctions, - VMap); - Module *Extracted = BD.ExtractMappedBlocksFromModule(Blocks, ToExtract); - if (Extracted == 0) { - // Weird, extraction should have worked. - errs() << "Nondeterministic problem extracting blocks??\n"; - delete ProgClone; - delete ToExtract; - return false; - } - - // Otherwise, block extraction succeeded. Link the two program fragments back - // together. - delete ToExtract; - - std::vector<std::pair<std::string, const FunctionType*> > MisCompFunctions; - for (Module::iterator I = Extracted->begin(), E = Extracted->end(); - I != E; ++I) - if (!I->isDeclaration()) - MisCompFunctions.push_back(std::make_pair(I->getName(), - I->getFunctionType())); - - std::string ErrorMsg; - if (Linker::LinkModules(ProgClone, Extracted, &ErrorMsg)) { - errs() << BD.getToolName() << ": Error linking modules together:" - << ErrorMsg << '\n'; - exit(1); - } - delete Extracted; - - // Set the new program and delete the old one. - BD.setNewProgram(ProgClone); - - // Update the list of miscompiled functions. - MiscompiledFunctions.clear(); - - for (unsigned i = 0, e = MisCompFunctions.size(); i != e; ++i) { - Function *NewF = ProgClone->getFunction(MisCompFunctions[i].first); - assert(NewF && "Function not found??"); - assert(NewF->getFunctionType() == MisCompFunctions[i].second && - "Function has wrong type??"); - MiscompiledFunctions.push_back(NewF); - } - - return true; -} - - -/// DebugAMiscompilation - This is a generic driver to narrow down -/// miscompilations, either in an optimization or a code generator. -/// -static std::vector<Function*> -DebugAMiscompilation(BugDriver &BD, - bool (*TestFn)(BugDriver &, Module *, Module *, - std::string &), - std::string &Error) { - // Okay, now that we have reduced the list of passes which are causing the - // failure, see if we can pin down which functions are being - // miscompiled... first build a list of all of the non-external functions in - // the program. - std::vector<Function*> MiscompiledFunctions; - Module *Prog = BD.getProgram(); - for (Module::iterator I = Prog->begin(), E = Prog->end(); I != E; ++I) - if (!I->isDeclaration()) - MiscompiledFunctions.push_back(I); - - // Do the reduction... - if (!BugpointIsInterrupted) - ReduceMiscompilingFunctions(BD, TestFn).reduceList(MiscompiledFunctions, - Error); - if (!Error.empty()) - return MiscompiledFunctions; - - outs() << "\n*** The following function" - << (MiscompiledFunctions.size() == 1 ? " is" : "s are") - << " being miscompiled: "; - PrintFunctionList(MiscompiledFunctions); - outs() << '\n'; - - // See if we can rip any loops out of the miscompiled functions and still - // trigger the problem. - - if (!BugpointIsInterrupted && !DisableLoopExtraction) { - bool Ret = ExtractLoops(BD, TestFn, MiscompiledFunctions, Error); - if (!Error.empty()) - return MiscompiledFunctions; - if (Ret) { - // Okay, we extracted some loops and the problem still appears. See if - // we can eliminate some of the created functions from being candidates. - DisambiguateGlobalSymbols(BD.getProgram()); - - // Do the reduction... - if (!BugpointIsInterrupted) - ReduceMiscompilingFunctions(BD, TestFn).reduceList(MiscompiledFunctions, - Error); - if (!Error.empty()) - return MiscompiledFunctions; - - outs() << "\n*** The following function" - << (MiscompiledFunctions.size() == 1 ? " is" : "s are") - << " being miscompiled: "; - PrintFunctionList(MiscompiledFunctions); - outs() << '\n'; - } - } - - if (!BugpointIsInterrupted && !DisableBlockExtraction) { - bool Ret = ExtractBlocks(BD, TestFn, MiscompiledFunctions, Error); - if (!Error.empty()) - return MiscompiledFunctions; - if (Ret) { - // Okay, we extracted some blocks and the problem still appears. See if - // we can eliminate some of the created functions from being candidates. - DisambiguateGlobalSymbols(BD.getProgram()); - - // Do the reduction... - ReduceMiscompilingFunctions(BD, TestFn).reduceList(MiscompiledFunctions, - Error); - if (!Error.empty()) - return MiscompiledFunctions; - - outs() << "\n*** The following function" - << (MiscompiledFunctions.size() == 1 ? " is" : "s are") - << " being miscompiled: "; - PrintFunctionList(MiscompiledFunctions); - outs() << '\n'; - } - } - - return MiscompiledFunctions; -} - -/// TestOptimizer - This is the predicate function used to check to see if the -/// "Test" portion of the program is misoptimized. If so, return true. In any -/// case, both module arguments are deleted. -/// -static bool TestOptimizer(BugDriver &BD, Module *Test, Module *Safe, - std::string &Error) { - // Run the optimization passes on ToOptimize, producing a transformed version - // of the functions being tested. - outs() << " Optimizing functions being tested: "; - Module *Optimized = BD.runPassesOn(Test, BD.getPassesToRun(), - /*AutoDebugCrashes*/true); - outs() << "done.\n"; - delete Test; - - outs() << " Checking to see if the merged program executes correctly: "; - bool Broken; - Module *New = TestMergedProgram(BD, Optimized, Safe, true, Error, Broken); - if (New) { - outs() << (Broken ? " nope.\n" : " yup.\n"); - // Delete the original and set the new program. - delete BD.swapProgramIn(New); - } - return Broken; -} - - -/// debugMiscompilation - This method is used when the passes selected are not -/// crashing, but the generated output is semantically different from the -/// input. -/// -void BugDriver::debugMiscompilation(std::string *Error) { - // Make sure something was miscompiled... - if (!BugpointIsInterrupted) - if (!ReduceMiscompilingPasses(*this).reduceList(PassesToRun, *Error)) { - if (Error->empty()) - errs() << "*** Optimized program matches reference output! No problem" - << " detected...\nbugpoint can't help you with your problem!\n"; - return; - } - - outs() << "\n*** Found miscompiling pass" - << (getPassesToRun().size() == 1 ? "" : "es") << ": " - << getPassesString(getPassesToRun()) << '\n'; - EmitProgressBitcode(Program, "passinput"); - - std::vector<Function *> MiscompiledFunctions = - DebugAMiscompilation(*this, TestOptimizer, *Error); - if (!Error->empty()) - return; - - // Output a bunch of bitcode files for the user... - outs() << "Outputting reduced bitcode files which expose the problem:\n"; - ValueMap<const Value*, Value*> VMap; - Module *ToNotOptimize = CloneModule(getProgram(), VMap); - Module *ToOptimize = SplitFunctionsOutOfModule(ToNotOptimize, - MiscompiledFunctions, - VMap); - - outs() << " Non-optimized portion: "; - EmitProgressBitcode(ToNotOptimize, "tonotoptimize", true); - delete ToNotOptimize; // Delete hacked module. - - outs() << " Portion that is input to optimizer: "; - EmitProgressBitcode(ToOptimize, "tooptimize"); - delete ToOptimize; // Delete hacked module. - - return; -} - -/// CleanupAndPrepareModules - Get the specified modules ready for code -/// generator testing. -/// -static void CleanupAndPrepareModules(BugDriver &BD, Module *&Test, - Module *Safe) { - // Clean up the modules, removing extra cruft that we don't need anymore... - Test = BD.performFinalCleanups(Test); - - // If we are executing the JIT, we have several nasty issues to take care of. - if (!BD.isExecutingJIT()) return; - - // First, if the main function is in the Safe module, we must add a stub to - // the Test module to call into it. Thus, we create a new function `main' - // which just calls the old one. - if (Function *oldMain = Safe->getFunction("main")) - if (!oldMain->isDeclaration()) { - // Rename it - oldMain->setName("llvm_bugpoint_old_main"); - // Create a NEW `main' function with same type in the test module. - Function *newMain = Function::Create(oldMain->getFunctionType(), - GlobalValue::ExternalLinkage, - "main", Test); - // Create an `oldmain' prototype in the test module, which will - // corresponds to the real main function in the same module. - Function *oldMainProto = Function::Create(oldMain->getFunctionType(), - GlobalValue::ExternalLinkage, - oldMain->getName(), Test); - // Set up and remember the argument list for the main function. - std::vector<Value*> args; - for (Function::arg_iterator - I = newMain->arg_begin(), E = newMain->arg_end(), - OI = oldMain->arg_begin(); I != E; ++I, ++OI) { - I->setName(OI->getName()); // Copy argument names from oldMain - args.push_back(I); - } - - // Call the old main function and return its result - BasicBlock *BB = BasicBlock::Create(Safe->getContext(), "entry", newMain); - CallInst *call = CallInst::Create(oldMainProto, args.begin(), args.end(), - "", BB); - - // If the type of old function wasn't void, return value of call - ReturnInst::Create(Safe->getContext(), call, BB); - } - - // The second nasty issue we must deal with in the JIT is that the Safe - // module cannot directly reference any functions defined in the test - // module. Instead, we use a JIT API call to dynamically resolve the - // symbol. - - // Add the resolver to the Safe module. - // Prototype: void *getPointerToNamedFunction(const char* Name) - Constant *resolverFunc = - Safe->getOrInsertFunction("getPointerToNamedFunction", - Type::getInt8PtrTy(Safe->getContext()), - Type::getInt8PtrTy(Safe->getContext()), - (Type *)0); - - // Use the function we just added to get addresses of functions we need. - for (Module::iterator F = Safe->begin(), E = Safe->end(); F != E; ++F) { - if (F->isDeclaration() && !F->use_empty() && &*F != resolverFunc && - !F->isIntrinsic() /* ignore intrinsics */) { - Function *TestFn = Test->getFunction(F->getName()); - - // Don't forward functions which are external in the test module too. - if (TestFn && !TestFn->isDeclaration()) { - // 1. Add a string constant with its name to the global file - Constant *InitArray = ConstantArray::get(F->getContext(), F->getName()); - GlobalVariable *funcName = - new GlobalVariable(*Safe, InitArray->getType(), true /*isConstant*/, - GlobalValue::InternalLinkage, InitArray, - F->getName() + "_name"); - - // 2. Use `GetElementPtr *funcName, 0, 0' to convert the string to an - // sbyte* so it matches the signature of the resolver function. - - // GetElementPtr *funcName, ulong 0, ulong 0 - std::vector<Constant*> GEPargs(2, - Constant::getNullValue(Type::getInt32Ty(F->getContext()))); - Value *GEP = - ConstantExpr::getGetElementPtr(funcName, &GEPargs[0], 2); - std::vector<Value*> ResolverArgs; - ResolverArgs.push_back(GEP); - - // Rewrite uses of F in global initializers, etc. to uses of a wrapper - // function that dynamically resolves the calls to F via our JIT API - if (!F->use_empty()) { - // Create a new global to hold the cached function pointer. - Constant *NullPtr = ConstantPointerNull::get(F->getType()); - GlobalVariable *Cache = - new GlobalVariable(*F->getParent(), F->getType(), - false, GlobalValue::InternalLinkage, - NullPtr,F->getName()+".fpcache"); - - // Construct a new stub function that will re-route calls to F - const FunctionType *FuncTy = F->getFunctionType(); - Function *FuncWrapper = Function::Create(FuncTy, - GlobalValue::InternalLinkage, - F->getName() + "_wrapper", - F->getParent()); - BasicBlock *EntryBB = BasicBlock::Create(F->getContext(), - "entry", FuncWrapper); - BasicBlock *DoCallBB = BasicBlock::Create(F->getContext(), - "usecache", FuncWrapper); - BasicBlock *LookupBB = BasicBlock::Create(F->getContext(), - "lookupfp", FuncWrapper); - - // Check to see if we already looked up the value. - Value *CachedVal = new LoadInst(Cache, "fpcache", EntryBB); - Value *IsNull = new ICmpInst(*EntryBB, ICmpInst::ICMP_EQ, CachedVal, - NullPtr, "isNull"); - BranchInst::Create(LookupBB, DoCallBB, IsNull, EntryBB); - - // Resolve the call to function F via the JIT API: - // - // call resolver(GetElementPtr...) - CallInst *Resolver = - CallInst::Create(resolverFunc, ResolverArgs.begin(), - ResolverArgs.end(), "resolver", LookupBB); - - // Cast the result from the resolver to correctly-typed function. - CastInst *CastedResolver = - new BitCastInst(Resolver, - PointerType::getUnqual(F->getFunctionType()), - "resolverCast", LookupBB); - - // Save the value in our cache. - new StoreInst(CastedResolver, Cache, LookupBB); - BranchInst::Create(DoCallBB, LookupBB); - - PHINode *FuncPtr = PHINode::Create(NullPtr->getType(), - "fp", DoCallBB); - FuncPtr->addIncoming(CastedResolver, LookupBB); - FuncPtr->addIncoming(CachedVal, EntryBB); - - // Save the argument list. - std::vector<Value*> Args; - for (Function::arg_iterator i = FuncWrapper->arg_begin(), - e = FuncWrapper->arg_end(); i != e; ++i) - Args.push_back(i); - - // Pass on the arguments to the real function, return its result - if (F->getReturnType()->isVoidTy()) { - CallInst::Create(FuncPtr, Args.begin(), Args.end(), "", DoCallBB); - ReturnInst::Create(F->getContext(), DoCallBB); - } else { - CallInst *Call = CallInst::Create(FuncPtr, Args.begin(), Args.end(), - "retval", DoCallBB); - ReturnInst::Create(F->getContext(),Call, DoCallBB); - } - - // Use the wrapper function instead of the old function - F->replaceAllUsesWith(FuncWrapper); - } - } - } - } - - if (verifyModule(*Test) || verifyModule(*Safe)) { - errs() << "Bugpoint has a bug, which corrupted a module!!\n"; - abort(); - } -} - - - -/// TestCodeGenerator - This is the predicate function used to check to see if -/// the "Test" portion of the program is miscompiled by the code generator under -/// test. If so, return true. In any case, both module arguments are deleted. -/// -static bool TestCodeGenerator(BugDriver &BD, Module *Test, Module *Safe, - std::string &Error) { - CleanupAndPrepareModules(BD, Test, Safe); - - sys::Path TestModuleBC("bugpoint.test.bc"); - std::string ErrMsg; - if (TestModuleBC.makeUnique(true, &ErrMsg)) { - errs() << BD.getToolName() << "Error making unique filename: " - << ErrMsg << "\n"; - exit(1); - } - if (BD.writeProgramToFile(TestModuleBC.str(), Test)) { - errs() << "Error writing bitcode to `" << TestModuleBC.str() - << "'\nExiting."; - exit(1); - } - delete Test; - - FileRemover TestModuleBCRemover(TestModuleBC, !SaveTemps); - - // Make the shared library - sys::Path SafeModuleBC("bugpoint.safe.bc"); - if (SafeModuleBC.makeUnique(true, &ErrMsg)) { - errs() << BD.getToolName() << "Error making unique filename: " - << ErrMsg << "\n"; - exit(1); - } - - if (BD.writeProgramToFile(SafeModuleBC.str(), Safe)) { - errs() << "Error writing bitcode to `" << SafeModuleBC.str() - << "'\nExiting."; - exit(1); - } - - FileRemover SafeModuleBCRemover(SafeModuleBC, !SaveTemps); - - std::string SharedObject = BD.compileSharedObject(SafeModuleBC.str(), Error); - if (!Error.empty()) - return false; - delete Safe; - - FileRemover SharedObjectRemover(sys::Path(SharedObject), !SaveTemps); - - // Run the code generator on the `Test' code, loading the shared library. - // The function returns whether or not the new output differs from reference. - bool Result = BD.diffProgram(BD.getProgram(), TestModuleBC.str(), - SharedObject, false, &Error); - if (!Error.empty()) - return false; - - if (Result) - errs() << ": still failing!\n"; - else - errs() << ": didn't fail.\n"; - - return Result; -} - - -/// debugCodeGenerator - debug errors in LLC, LLI, or CBE. -/// -bool BugDriver::debugCodeGenerator(std::string *Error) { - if ((void*)SafeInterpreter == (void*)Interpreter) { - std::string Result = executeProgramSafely(Program, "bugpoint.safe.out", - Error); - if (Error->empty()) { - outs() << "\n*** The \"safe\" i.e. 'known good' backend cannot match " - << "the reference diff. This may be due to a\n front-end " - << "bug or a bug in the original program, but this can also " - << "happen if bugpoint isn't running the program with the " - << "right flags or input.\n I left the result of executing " - << "the program with the \"safe\" backend in this file for " - << "you: '" - << Result << "'.\n"; - } - return true; - } - - DisambiguateGlobalSymbols(Program); - - std::vector<Function*> Funcs = DebugAMiscompilation(*this, TestCodeGenerator, - *Error); - if (!Error->empty()) - return true; - - // Split the module into the two halves of the program we want. - ValueMap<const Value*, Value*> VMap; - Module *ToNotCodeGen = CloneModule(getProgram(), VMap); - Module *ToCodeGen = SplitFunctionsOutOfModule(ToNotCodeGen, Funcs, VMap); - - // Condition the modules - CleanupAndPrepareModules(*this, ToCodeGen, ToNotCodeGen); - - sys::Path TestModuleBC("bugpoint.test.bc"); - std::string ErrMsg; - if (TestModuleBC.makeUnique(true, &ErrMsg)) { - errs() << getToolName() << "Error making unique filename: " - << ErrMsg << "\n"; - exit(1); - } - - if (writeProgramToFile(TestModuleBC.str(), ToCodeGen)) { - errs() << "Error writing bitcode to `" << TestModuleBC.str() - << "'\nExiting."; - exit(1); - } - delete ToCodeGen; - - // Make the shared library - sys::Path SafeModuleBC("bugpoint.safe.bc"); - if (SafeModuleBC.makeUnique(true, &ErrMsg)) { - errs() << getToolName() << "Error making unique filename: " - << ErrMsg << "\n"; - exit(1); - } - - if (writeProgramToFile(SafeModuleBC.str(), ToNotCodeGen)) { - errs() << "Error writing bitcode to `" << SafeModuleBC.str() - << "'\nExiting."; - exit(1); - } - std::string SharedObject = compileSharedObject(SafeModuleBC.str(), *Error); - if (!Error->empty()) - return true; - delete ToNotCodeGen; - - outs() << "You can reproduce the problem with the command line: \n"; - if (isExecutingJIT()) { - outs() << " lli -load " << SharedObject << " " << TestModuleBC.str(); - } else { - outs() << " llc " << TestModuleBC.str() << " -o " << TestModuleBC.str() - << ".s\n"; - outs() << " gcc " << SharedObject << " " << TestModuleBC.str() - << ".s -o " << TestModuleBC.str() << ".exe"; -#if defined (HAVE_LINK_R) - outs() << " -Wl,-R."; -#endif - outs() << "\n"; - outs() << " " << TestModuleBC.str() << ".exe"; - } - for (unsigned i = 0, e = InputArgv.size(); i != e; ++i) - outs() << " " << InputArgv[i]; - outs() << '\n'; - outs() << "The shared object was created with:\n llc -march=c " - << SafeModuleBC.str() << " -o temporary.c\n" - << " gcc -xc temporary.c -O2 -o " << SharedObject; - if (TargetTriple.getArch() == Triple::sparc) - outs() << " -G"; // Compile a shared library, `-G' for Sparc - else - outs() << " -fPIC -shared"; // `-shared' for Linux/X86, maybe others - - outs() << " -fno-strict-aliasing\n"; - - return false; -} |
