X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=tools%2Fbugpoint%2FMiscompilation.cpp;h=00f26fe823a96b3adedf551b43ab0d3ff1347c1a;hb=86c006a971eb6fab6bd4923ff7ec1c0bc9c28f74;hp=fa60aa57f4a9d91d065a2a41b7788fe8bea3e99c;hpb=dc7fef83dcab053f86119d00478e6b008166fcf5;p=oota-llvm.git diff --git a/tools/bugpoint/Miscompilation.cpp b/tools/bugpoint/Miscompilation.cpp index fa60aa57f4a..00f26fe823a 100644 --- a/tools/bugpoint/Miscompilation.cpp +++ b/tools/bugpoint/Miscompilation.cpp @@ -1,10 +1,10 @@ //===- Miscompilation.cpp - Debug program miscompilations -----------------===// -// +// // 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 is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// //===----------------------------------------------------------------------===// // // This file implements optimizer and code generation miscompilation debugging @@ -17,14 +17,15 @@ #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/Support/Mangler.h" #include "llvm/Transforms/Utils/Cloning.h" -#include "llvm/Transforms/Utils/Linker.h" -#include "Support/CommandLine.h" -#include "Support/FileUtilities.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 { @@ -32,102 +33,123 @@ namespace llvm { } namespace { + static llvm::cl::opt + DisableLoopExtraction("disable-loop-extraction", + cl::desc("Don't extract loops when searching for miscompilations"), + cl::init(false)); + static llvm::cl::opt + DisableBlockExtraction("disable-block-extraction", + cl::desc("Don't extract blocks when searching for miscompilations"), + cl::init(false)); + class ReduceMiscompilingPasses : public ListReducer { BugDriver &BD; public: ReduceMiscompilingPasses(BugDriver &bd) : BD(bd) {} - + virtual TestResult doTest(std::vector &Prefix, std::vector &Suffix); }; } +/// 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 &Prefix, std::vector &Suffix) { // First, run the program with just the Suffix passes. If it is still broken // with JUST the kept passes, discard the prefix passes. - std::cout << "Checking to see if '" << getPassesString(Suffix) - << "' compile correctly: "; + outs() << "Checking to see if '" << getPassesString(Suffix) + << "' compiles correctly: "; - std::string BytecodeResult; - if (BD.runPasses(Suffix, BytecodeResult, false/*delete*/, true/*quiet*/)) { - std::cerr << " Error running this sequence of passes" - << " on the input program!\n"; + std::string BitcodeResult; + if (BD.runPasses(Suffix, BitcodeResult, false/*delete*/, true/*quiet*/)) { + errs() << " Error running this sequence of passes" + << " on the input program!\n"; BD.setPassesToRun(Suffix); - BD.EmitProgressBytecode("pass-error", false); + BD.EmitProgressBitcode("pass-error", false); exit(BD.debugOptimizerCrash()); } - + // Check to see if the finished program matches the reference output... - if (BD.diffProgram(BytecodeResult, "", true /*delete bytecode*/)) { - std::cout << "nope.\n"; - return KeepSuffix; // Miscompilation detected! + if (BD.diffProgram(BitcodeResult, "", true /*delete bitcode*/)) { + 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! } - std::cout << "yup.\n"; // No miscompilation! + 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. - std::cout << "Checking to see if '" << getPassesString(Prefix) - << "' compile correctly: "; + 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 bytecode file to include the result of the + // kept passes, we can update our bitcode file to include the result of the // prefix passes, then discard the prefix passes. // - if (BD.runPasses(Prefix, BytecodeResult, false/*delete*/, true/*quiet*/)) { - std::cerr << " Error running this sequence of passes" - << " on the input program!\n"; + if (BD.runPasses(Prefix, BitcodeResult, false/*delete*/, true/*quiet*/)) { + errs() << " Error running this sequence of passes" + << " on the input program!\n"; BD.setPassesToRun(Prefix); - BD.EmitProgressBytecode("pass-error", false); + BD.EmitProgressBitcode("pass-error", false); exit(BD.debugOptimizerCrash()); } // If the prefix maintains the predicate by itself, only keep the prefix! - if (BD.diffProgram(BytecodeResult)) { - std::cout << "nope.\n"; - removeFile(BytecodeResult); + if (BD.diffProgram(BitcodeResult)) { + outs() << " nope.\n"; + sys::Path(BitcodeResult).eraseFromDisk(); return KeepPrefix; } - std::cout << "yup.\n"; // No miscompilation! + 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. // - Module *PrefixOutput = ParseInputFile(BytecodeResult); + Module *PrefixOutput = ParseInputFile(BitcodeResult, BD.getContext()); if (PrefixOutput == 0) { - std::cerr << BD.getToolName() << ": Error reading bytecode file '" - << BytecodeResult << "'!\n"; + errs() << BD.getToolName() << ": Error reading bitcode file '" + << BitcodeResult << "'!\n"; exit(1); } - removeFile(BytecodeResult); // No longer need the file on disk - - std::cout << "Checking to see if '" << getPassesString(Suffix) + 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: "; Module *OriginalInput = BD.swapProgramIn(PrefixOutput); - if (BD.runPasses(Suffix, BytecodeResult, false/*delete*/, true/*quiet*/)) { - std::cerr << " Error running this sequence of passes" - << " on the input program!\n"; + if (BD.runPasses(Suffix, BitcodeResult, false/*delete*/, true/*quiet*/)) { + errs() << " Error running this sequence of passes" + << " on the input program!\n"; BD.setPassesToRun(Suffix); - BD.EmitProgressBytecode("pass-error", false); + BD.EmitProgressBitcode("pass-error", false); exit(BD.debugOptimizerCrash()); } // Run the result... - if (BD.diffProgram(BytecodeResult, "", true/*delete bytecode*/)) { - std::cout << "nope.\n"; + if (BD.diffProgram(BitcodeResult, "", true/*delete bitcode*/)) { + outs() << " nope.\n"; delete OriginalInput; // We pruned down the original input... return KeepSuffix; } // Otherwise, we must not be running the bad pass anymore. - std::cout << "yup.\n"; // No miscompilation! + outs() << " yup.\n"; // No miscompilation! delete BD.swapProgramIn(OriginalInput); // Restore orig program & free test return NoFailure; } @@ -140,7 +162,7 @@ namespace { ReduceMiscompilingFunctions(BugDriver &bd, bool (*F)(BugDriver &, Module *, Module *)) : BD(bd), TestFn(F) {} - + virtual TestResult doTest(std::vector &Prefix, std::vector &Suffix) { if (!Suffix.empty() && TestFuncs(Suffix)) @@ -149,7 +171,7 @@ namespace { return KeepPrefix; return NoFailure; } - + bool TestFuncs(const std::vector &Prefix); }; } @@ -159,17 +181,21 @@ namespace { /// matches, return false, otherwise return true. If the DeleteInputs argument /// is set to true then this function deletes both input modules before it /// returns. +/// static bool TestMergedProgram(BugDriver &BD, Module *M1, Module *M2, bool DeleteInputs) { // Link the two portions of the program back to together. std::string ErrorMsg; - if (!DeleteInputs) M1 = CloneModule(M1); - if (LinkModules(M1, M2, &ErrorMsg)) { - std::cerr << BD.getToolName() << ": Error linking modules together:" - << ErrorMsg << "\n"; + 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); } - if (DeleteInputs) delete M2; // We are done with this module... + delete M2; // We are done with this module. Module *OldProgram = BD.swapProgramIn(M1); @@ -183,24 +209,33 @@ static bool TestMergedProgram(BugDriver &BD, Module *M1, Module *M2, return Broken; } +/// 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&Funcs){ // Test to see if the function is misoptimized if we ONLY run it on the // functions listed in Funcs. - std::cout << "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") << ":"; + 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); - std::cout << "\n"; + outs() << '\n'; // Split the module into the two halves of the program we want. - Module *ToNotOptimize = CloneModule(BD.getProgram()); - Module *ToOptimize = SplitFunctionsOutOfModule(ToNotOptimize, Funcs); + DenseMap ValueMap; + Module *ToNotOptimize = CloneModule(BD.getProgram(), ValueMap); + Module *ToOptimize = SplitFunctionsOutOfModule(ToNotOptimize, Funcs, + ValueMap); - // Run the predicate, not that the predicate will delete both input modules. + // Run the predicate, note that the predicate will delete both input modules. return TestFn(BD, ToOptimize, ToNotOptimize); } +/// DisambiguateGlobalSymbols - Mangle symbols to guarantee uniqueness by +/// modifying predominantly internal symbols rather than external ones. +/// static void DisambiguateGlobalSymbols(Module *M) { // Try not to cause collisions by minimizing chances of renaming an // already-external symbol, so take in external globals and functions as-is. @@ -208,23 +243,38 @@ static void DisambiguateGlobalSymbols(Module *M) { // mangler is used by the two code generators), but having symbols with the // same name causes warnings to be emitted by the code generator. Mangler Mang(*M); - for (Module::giterator I = M->gbegin(), E = M->gend(); I != E; ++I) - I->setName(Mang.getValueName(I)); - for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I) - I->setName(Mang.getValueName(I)); + // Agree with the CBE on symbol naming + Mang.markCharUnacceptable('.'); + for (Module::global_iterator I = M->global_begin(), E = M->global_end(); + I != E; ++I) { + // Don't mangle asm names. + if (!I->hasName() || I->getName()[0] != 1) + I->setName(Mang.getMangledName(I)); + } + for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I) { + // Don't mangle asm names or intrinsics. + if ((!I->hasName() || I->getName()[0] != 1) && + I->getIntrinsicID() == 0) + I->setName(Mang.getMangledName(I)); + } } /// 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::vector &MiscompiledFunctions) { bool MadeChange = false; while (1) { - Module *ToNotOptimize = CloneModule(BD.getProgram()); + if (BugpointIsInterrupted) return MadeChange; + + DenseMap ValueMap; + Module *ToNotOptimize = CloneModule(BD.getProgram(), ValueMap); Module *ToOptimize = SplitFunctionsOutOfModule(ToNotOptimize, - MiscompiledFunctions); + MiscompiledFunctions, + ValueMap); Module *ToOptimizeLoopExtracted = BD.ExtractLoop(ToOptimize); if (!ToOptimizeLoopExtracted) { // If the loop extractor crashed or if there were no extractible loops, @@ -234,34 +284,42 @@ static bool ExtractLoops(BugDriver &BD, return MadeChange; } - std::cerr << "Extracted a loop from the breaking portion of the program.\n"; - delete ToOptimize; + 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.switchToCBE(); + AbstractInterpreter *AI = BD.switchToSafeInterpreter(); if (TestMergedProgram(BD, ToOptimizeLoopExtracted, ToNotOptimize, false)) { BD.switchToInterpreter(AI); // Merged program doesn't work anymore! - std::cerr << " *** ERROR: Loop extraction broke the program. :(" - << " Please report a bug!\n"; - std::cerr << " Continuing on with un-loop-extracted version.\n"; + errs() << " *** ERROR: Loop extraction broke the program. :(" + << " Please report a bug!\n"; + errs() << " Continuing on with un-loop-extracted version.\n"; + + BD.writeProgramToFile("bugpoint-loop-extract-fail-tno.bc", ToNotOptimize); + BD.writeProgramToFile("bugpoint-loop-extract-fail-to.bc", ToOptimize); + BD.writeProgramToFile("bugpoint-loop-extract-fail-to-le.bc", + ToOptimizeLoopExtracted); + + errs() << "Please submit the bugpoint-loop-extract-fail-*.bc files.\n"; + delete ToOptimize; delete ToNotOptimize; delete ToOptimizeLoopExtracted; return MadeChange; } + delete ToOptimize; BD.switchToInterpreter(AI); - - std::cout << " Testing after loop extraction:\n"; + + outs() << " Testing after loop extraction:\n"; // Clone modules, the tester function will free them. Module *TOLEBackup = CloneModule(ToOptimizeLoopExtracted); Module *TNOBackup = CloneModule(ToNotOptimize); if (!TestFn(BD, ToOptimizeLoopExtracted, ToNotOptimize)) { - std::cout << "*** Loop extraction masked the problem. Undoing.\n"; + 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; @@ -271,41 +329,190 @@ static bool ExtractLoops(BugDriver &BD, ToOptimizeLoopExtracted = TOLEBackup; ToNotOptimize = TNOBackup; - std::cout << "*** Loop extraction successful!\n"; + outs() << "*** Loop extraction successful!\n"; + + std::vector > 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 (LinkModules(ToNotOptimize, ToOptimizeLoopExtracted, &ErrorMsg)) { - std::cerr << BD.getToolName() << ": Error linking modules together:" - << ErrorMsg << "\n"; + 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 (Module::iterator I = ToOptimizeLoopExtracted->begin(), - E = ToOptimizeLoopExtracted->end(); I != E; ++I) { - if (!I->isExternal()) { - Function *NewF = ToNotOptimize->getFunction(I->getName(), - I->getFunctionType()); - assert(NewF && "Function not found??"); - MiscompiledFunctions.push_back(NewF); - } + 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); } - delete ToOptimizeLoopExtracted; BD.setNewProgram(ToNotOptimize); MadeChange = true; } } +namespace { + class ReduceMiscompiledBlocks : public ListReducer { + BugDriver &BD; + bool (*TestFn)(BugDriver &, Module *, Module *); + std::vector FunctionsBeingTested; + public: + ReduceMiscompiledBlocks(BugDriver &bd, + bool (*F)(BugDriver &, Module *, Module *), + const std::vector &Fns) + : BD(bd), TestFn(F), FunctionsBeingTested(Fns) {} + + virtual TestResult doTest(std::vector &Prefix, + std::vector &Suffix) { + if (!Suffix.empty() && TestFuncs(Suffix)) + return KeepSuffix; + if (TestFuncs(Prefix)) + return KeepPrefix; + return NoFailure; + } + + bool TestFuncs(const std::vector &Prefix); + }; +} + +/// 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 &BBs) { + // 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. + DenseMap ValueMap; + Module *ToNotOptimize = CloneModule(BD.getProgram(), ValueMap); + Module *ToOptimize = SplitFunctionsOutOfModule(ToNotOptimize, + FunctionsBeingTested, + ValueMap); + + // 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(BBs, ToOptimize)) { + delete ToOptimize; + // Run the predicate, not that the predicate will delete both input modules. + return TestFn(BD, New, ToNotOptimize); + } + 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::vector &MiscompiledFunctions) { + if (BugpointIsInterrupted) return false; + + std::vector 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. + if (ReduceMiscompiledBlocks(BD, TestFn, + MiscompiledFunctions).TestFuncs(std::vector())) { + Blocks.clear(); + } else { + ReduceMiscompiledBlocks(BD, TestFn,MiscompiledFunctions).reduceList(Blocks); + if (Blocks.size() == OldSize) + return false; + } + + DenseMap ValueMap; + Module *ProgClone = CloneModule(BD.getProgram(), ValueMap); + Module *ToExtract = SplitFunctionsOutOfModule(ProgClone, + MiscompiledFunctions, + ValueMap); + 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 > 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 DebugAMiscompilation(BugDriver &BD, bool (*TestFn)(BugDriver &, Module *, Module *)) { @@ -316,21 +523,24 @@ DebugAMiscompilation(BugDriver &BD, std::vector MiscompiledFunctions; Module *Prog = BD.getProgram(); for (Module::iterator I = Prog->begin(), E = Prog->end(); I != E; ++I) - if (!I->isExternal()) + if (!I->isDeclaration()) MiscompiledFunctions.push_back(I); // Do the reduction... - ReduceMiscompilingFunctions(BD, TestFn).reduceList(MiscompiledFunctions); + if (!BugpointIsInterrupted) + ReduceMiscompilingFunctions(BD, TestFn).reduceList(MiscompiledFunctions); - std::cout << "\n*** The following function" - << (MiscompiledFunctions.size() == 1 ? " is" : "s are") - << " being miscompiled: "; + outs() << "\n*** The following function" + << (MiscompiledFunctions.size() == 1 ? " is" : "s are") + << " being miscompiled: "; PrintFunctionList(MiscompiledFunctions); - std::cout << "\n"; + outs() << '\n'; // See if we can rip any loops out of the miscompiled functions and still // trigger the problem. - if (ExtractLoops(BD, TestFn, MiscompiledFunctions)) { + + if (!BugpointIsInterrupted && !DisableLoopExtraction && + ExtractLoops(BD, TestFn, MiscompiledFunctions)) { // Okay, we extracted some loops and the problem still appears. See if we // can eliminate some of the created functions from being candidates. @@ -339,14 +549,35 @@ DebugAMiscompilation(BugDriver &BD, // apart that we can link it back together again. DisambiguateGlobalSymbols(BD.getProgram()); + // Do the reduction... + if (!BugpointIsInterrupted) + ReduceMiscompilingFunctions(BD, TestFn).reduceList(MiscompiledFunctions); + + outs() << "\n*** The following function" + << (MiscompiledFunctions.size() == 1 ? " is" : "s are") + << " being miscompiled: "; + PrintFunctionList(MiscompiledFunctions); + outs() << '\n'; + } + + if (!BugpointIsInterrupted && !DisableBlockExtraction && + ExtractBlocks(BD, TestFn, MiscompiledFunctions)) { + // Okay, we extracted some blocks and the problem still appears. See if we + // can eliminate some of the created functions from being candidates. + + // Block extraction can introduce functions with the same name (foo_code). + // Make sure to disambiguate the symbols so that when the program is split + // apart that we can link it back together again. + DisambiguateGlobalSymbols(BD.getProgram()); + // Do the reduction... ReduceMiscompilingFunctions(BD, TestFn).reduceList(MiscompiledFunctions); - - std::cout << "\n*** The following function" - << (MiscompiledFunctions.size() == 1 ? " is" : "s are") - << " being miscompiled: "; + + outs() << "\n*** The following function" + << (MiscompiledFunctions.size() == 1 ? " is" : "s are") + << " being miscompiled: "; PrintFunctionList(MiscompiledFunctions); - std::cout << "\n"; + outs() << '\n'; } return MiscompiledFunctions; @@ -355,18 +586,19 @@ DebugAMiscompilation(BugDriver &BD, /// 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) { // Run the optimization passes on ToOptimize, producing a transformed version // of the functions being tested. - std::cout << " Optimizing functions being tested: "; + outs() << " Optimizing functions being tested: "; Module *Optimized = BD.runPassesOn(Test, BD.getPassesToRun(), /*AutoDebugCrashes*/true); - std::cout << "done.\n"; + outs() << "done.\n"; delete Test; - std::cout << " Checking to see if the merged program executes correctly: "; + outs() << " Checking to see if the merged program executes correctly: "; bool Broken = TestMergedProgram(BD, Optimized, Safe, true); - std::cout << (Broken ? " nope.\n" : " yup.\n"); + outs() << (Broken ? " nope.\n" : " yup.\n"); return Broken; } @@ -377,34 +609,37 @@ static bool TestOptimizer(BugDriver &BD, Module *Test, Module *Safe) { /// bool BugDriver::debugMiscompilation() { // Make sure something was miscompiled... - if (!ReduceMiscompilingPasses(*this).reduceList(PassesToRun)) { - std::cerr << "*** Optimized program matches reference output! No problem " - << "detected...\nbugpoint can't help you with your problem!\n"; - return false; - } + if (!BugpointIsInterrupted) + if (!ReduceMiscompilingPasses(*this).reduceList(PassesToRun)) { + errs() << "*** Optimized program matches reference output! No problem" + << " detected...\nbugpoint can't help you with your problem!\n"; + return false; + } - std::cout << "\n*** Found miscompiling pass" - << (getPassesToRun().size() == 1 ? "" : "es") << ": " - << getPassesString(getPassesToRun()) << "\n"; - EmitProgressBytecode("passinput"); + outs() << "\n*** Found miscompiling pass" + << (getPassesToRun().size() == 1 ? "" : "es") << ": " + << getPassesString(getPassesToRun()) << '\n'; + EmitProgressBitcode("passinput"); std::vector MiscompiledFunctions = DebugAMiscompilation(*this, TestOptimizer); - // Output a bunch of bytecode files for the user... - std::cout << "Outputting reduced bytecode files which expose the problem:\n"; - Module *ToNotOptimize = CloneModule(getProgram()); + // Output a bunch of bitcode files for the user... + outs() << "Outputting reduced bitcode files which expose the problem:\n"; + DenseMap ValueMap; + Module *ToNotOptimize = CloneModule(getProgram(), ValueMap); Module *ToOptimize = SplitFunctionsOutOfModule(ToNotOptimize, - MiscompiledFunctions); + MiscompiledFunctions, + ValueMap); - std::cout << " Non-optimized portion: "; + outs() << " Non-optimized portion: "; ToNotOptimize = swapProgramIn(ToNotOptimize); - EmitProgressBytecode("tonotoptimize", true); + EmitProgressBitcode("tonotoptimize", true); setNewProgram(ToNotOptimize); // Delete hacked module. - - std::cout << " Portion that is input to optimizer: "; + + outs() << " Portion that is input to optimizer: "; ToOptimize = swapProgramIn(ToOptimize); - EmitProgressBytecode("tooptimize"); + EmitProgressBitcode("tooptimize"); setNewProgram(ToOptimize); // Delete hacked module. return false; @@ -412,6 +647,7 @@ bool BugDriver::debugMiscompilation() { /// 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... @@ -423,178 +659,147 @@ static void CleanupAndPrepareModules(BugDriver &BD, Module *&Test, // 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->getNamedFunction("main")) - if (!oldMain->isExternal()) { + 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 = new Function(oldMain->getFunctionType(), - GlobalValue::ExternalLinkage, - "main", Test); + 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 = new Function(oldMain->getFunctionType(), - GlobalValue::ExternalLinkage, - oldMain->getName(), Test); + Function *oldMainProto = Function::Create(oldMain->getFunctionType(), + GlobalValue::ExternalLinkage, + oldMain->getName(), Test); // Set up and remember the argument list for the main function. std::vector args; - for (Function::aiterator I = newMain->abegin(), E = newMain->aend(), - OI = oldMain->abegin(); I != E; ++I, ++OI) { + 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 = new BasicBlock("entry", newMain); - CallInst *call = new CallInst(oldMainProto, args); - BB->getInstList().push_back(call); - + BasicBlock *BB = BasicBlock::Create("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 - new ReturnInst(oldMain->getReturnType() != Type::VoidTy ? call : 0, BB); + ReturnInst::Create(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) - Function *resolverFunc = + Constant *resolverFunc = Safe->getOrInsertFunction("getPointerToNamedFunction", - PointerType::get(Type::SByteTy), - PointerType::get(Type::SByteTy), 0); - + PointerType::getUnqual(Type::Int8Ty), + PointerType::getUnqual(Type::Int8Ty), (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->isExternal() && !F->use_empty() && &*F != resolverFunc && - F->getIntrinsicID() == 0 /* ignore intrinsics */) { - Function *TestFn = Test->getFunction(F->getName(), F->getFunctionType()); + 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->isExternal()) { + if (TestFn && !TestFn->isDeclaration()) { // 1. Add a string constant with its name to the global file Constant *InitArray = ConstantArray::get(F->getName()); GlobalVariable *funcName = - new GlobalVariable(InitArray->getType(), true /*isConstant*/, - GlobalValue::InternalLinkage, InitArray, - F->getName() + "_name", Safe); + 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 GEPargs(2,Constant::getNullValue(Type::IntTy)); + std::vector GEPargs(2, Constant::getNullValue(Type::Int32Ty)); Value *GEP = - ConstantExpr::getGetElementPtr(ConstantPointerRef::get(funcName), - GEPargs); + ConstantExpr::getGetElementPtr(funcName, &GEPargs[0], 2); std::vector ResolverArgs; ResolverArgs.push_back(GEP); - // Convert uses of F in global initializers, etc. to uses in - // instructions, which are then fixed-up below - std::vector Users(F->use_begin(), F->use_end()); - for (std::vector::iterator U = Users.begin(), UE = Users.end(); - U != UE; ++U) - { - User *Use = *U; - if (Instruction *Inst = dyn_cast(Use)) - continue; // Will be taken care of below - - // Take care of cases where a function is used by something other - // than an instruction; e.g., global variable initializers and - // constant expressions. - // - // Create a new wrapper function with the same signature as the old - // function which will just pass the call to the other function. The - // use of the other function will then be re-written (below) to look - // up the function by name. - + // 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 = new Function(FuncTy, F->getLinkage(), - F->getName() + "_wrapper", - F->getParent()); - BasicBlock *Header = new BasicBlock("header", FuncWrapper); - - // Save the argument list + Function *FuncWrapper = Function::Create(FuncTy, + GlobalValue::InternalLinkage, + F->getName() + "_wrapper", + F->getParent()); + BasicBlock *EntryBB = BasicBlock::Create("entry", FuncWrapper); + BasicBlock *DoCallBB = BasicBlock::Create("usecache", FuncWrapper); + BasicBlock *LookupBB = BasicBlock::Create("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 Args; - for (Function::aiterator i = FuncWrapper->abegin(), - e = FuncWrapper->aend(); i != e; ++i) + 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() == Type::VoidTy) { - CallInst *Call = new CallInst(F, Args); - Header->getInstList().push_back(Call); - ReturnInst *Ret = new ReturnInst(); - Header->getInstList().push_back(Ret); + CallInst::Create(FuncPtr, Args.begin(), Args.end(), "", DoCallBB); + ReturnInst::Create(DoCallBB); } else { - CallInst *Call = new CallInst(F, Args, "redir"); - Header->getInstList().push_back(Call); - ReturnInst *Ret = new ReturnInst(Call); - Header->getInstList().push_back(Ret); + CallInst *Call = CallInst::Create(FuncPtr, Args.begin(), Args.end(), + "retval", DoCallBB); + ReturnInst::Create(Call, DoCallBB); } - // Replace uses of old function with our wrapper - if (GlobalVariable *GV = dyn_cast(Use)) { - Constant *Init = GV->getInitializer(); - // Functions should only be used as pointers in arrays and structs; - // if any other uses come up, they must be handled here - if (ConstantArray *CA = dyn_cast(Init)) - CA->replaceUsesOfWithOnConstant(F, FuncWrapper); - else if (ConstantStruct *CS = dyn_cast(Init)) - CS->replaceUsesOfWithOnConstant(F, FuncWrapper); - else { - std::cerr << "UNHANDLED global initializer: " << *Init << "\n"; - exit(1); - } - } else if (Constant *C = dyn_cast(Use)) { - // no need to do anything for constants - } else if (Function *FuncUser = dyn_cast(Use)) { - // no need to do anything for function declarations - } else { - std::cerr << "UNHANDLED non-instruction use, not a global: " - << *Use << "\ntype: " << *Use->getType() << "\n"; - exit(1); - } - } - - // 3. Replace all uses of `func' with calls to resolver by: - // (a) Iterating through the list of uses of this function - // (b) Insert a cast instruction in front of each use - // (c) Replace use of old call with new call - - // Insert code at the beginning of the function - std::vector Uses(F->use_begin(), F->use_end()); - for (std::vector::iterator U = Uses.begin(), UE = Uses.end(); - U != UE; ++U) { - User *Use = *U; - if (Instruction *Inst = dyn_cast(Use)) { - // call resolver(GetElementPtr...) - CallInst *resolve = new CallInst(resolverFunc, ResolverArgs, - "resolver", Inst); - // cast the result from the resolver to correctly-typed function - CastInst *castResolver = - new CastInst(resolve, PointerType::get(F->getFunctionType()), - "resolverCast", Inst); - // actually use the resolved function - Inst->replaceUsesOfWith(F, castResolver); - } else if (Constant *C = dyn_cast(Use)) { - // no need to do anything for constants - } else if (Function *FuncUser = dyn_cast(Use)) { - // no need to do anything for function declarations - } else { - std::cerr << "UNHANDLED: use of function not rewritten to become " - << "an instruction: " << *Use << "\n"; - exit(1); - } + // Use the wrapper function instead of the old function + F->replaceAllUsesWith(FuncWrapper); } } } } if (verifyModule(*Test) || verifyModule(*Safe)) { - std::cerr << "Bugpoint has a bug, which corrupted a module!!\n"; + errs() << "Bugpoint has a bug, which corrupted a module!!\n"; abort(); } } @@ -604,51 +809,67 @@ static void CleanupAndPrepareModules(BugDriver &BD, Module *&Test, /// 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) { CleanupAndPrepareModules(BD, Test, Safe); - std::string TestModuleBC = getUniqueFilename("bugpoint.test.bc"); - if (BD.writeProgramToFile(TestModuleBC, Test)) { - std::cerr << "Error writing bytecode to `" << TestModuleBC << "'\nExiting."; + 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.toString(), Test)) { + errs() << "Error writing bitcode to `" << TestModuleBC << "'\nExiting."; exit(1); } delete Test; // Make the shared library - std::string SafeModuleBC = getUniqueFilename("bugpoint.safe.bc"); + 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, Safe)) { - std::cerr << "Error writing bytecode to `" << SafeModuleBC << "'\nExiting."; + if (BD.writeProgramToFile(SafeModuleBC.toString(), Safe)) { + errs() << "Error writing bitcode to `" << SafeModuleBC << "'\nExiting."; exit(1); } - std::string SharedObject = BD.compileSharedObject(SafeModuleBC); + std::string SharedObject = BD.compileSharedObject(SafeModuleBC.toString()); delete Safe; // Run the code generator on the `Test' code, loading the shared library. // The function returns whether or not the new output differs from reference. - int Result = BD.diffProgram(TestModuleBC, SharedObject, false); + int Result = BD.diffProgram(TestModuleBC.toString(), SharedObject, false); if (Result) - std::cerr << ": still failing!\n"; + errs() << ": still failing!\n"; else - std::cerr << ": didn't fail.\n"; - removeFile(TestModuleBC); - removeFile(SafeModuleBC); - removeFile(SharedObject); + errs() << ": didn't fail.\n"; + TestModuleBC.eraseFromDisk(); + SafeModuleBC.eraseFromDisk(); + sys::Path(SharedObject).eraseFromDisk(); return Result; } +/// debugCodeGenerator - debug errors in LLC, LLI, or CBE. +/// bool BugDriver::debugCodeGenerator() { - if ((void*)cbe == (void*)Interpreter) { - std::string Result = executeProgramWithCBE("bugpoint.cbe.out"); - std::cout << "\n*** The C backend cannot match the reference diff, but it " - << "is used as the 'known good'\n code generator, so I can't" - << " debug it. Perhaps you have a front-end problem?\n As a" - << " sanity check, I left the result of executing the program " - << "with the C backend\n in this file for you: '" - << Result << "'.\n"; + if ((void*)SafeInterpreter == (void*)Interpreter) { + std::string Result = executeProgramSafely("bugpoint.safe.out"); + 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; } @@ -657,49 +878,67 @@ bool BugDriver::debugCodeGenerator() { std::vector Funcs = DebugAMiscompilation(*this, TestCodeGenerator); // Split the module into the two halves of the program we want. - Module *ToNotCodeGen = CloneModule(getProgram()); - Module *ToCodeGen = SplitFunctionsOutOfModule(ToNotCodeGen, Funcs); + DenseMap ValueMap; + Module *ToNotCodeGen = CloneModule(getProgram(), ValueMap); + Module *ToCodeGen = SplitFunctionsOutOfModule(ToNotCodeGen, Funcs, ValueMap); // Condition the modules CleanupAndPrepareModules(*this, ToCodeGen, ToNotCodeGen); - std::string TestModuleBC = getUniqueFilename("bugpoint.test.bc"); - if (writeProgramToFile(TestModuleBC, ToCodeGen)) { - std::cerr << "Error writing bytecode to `" << TestModuleBC << "'\nExiting."; + 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.toString(), ToCodeGen)) { + errs() << "Error writing bitcode to `" << TestModuleBC << "'\nExiting."; exit(1); } delete ToCodeGen; // Make the shared library - std::string SafeModuleBC = getUniqueFilename("bugpoint.safe.bc"); - if (writeProgramToFile(SafeModuleBC, ToNotCodeGen)) { - std::cerr << "Error writing bytecode to `" << SafeModuleBC << "'\nExiting."; + sys::Path SafeModuleBC("bugpoint.safe.bc"); + if (SafeModuleBC.makeUnique(true, &ErrMsg)) { + errs() << getToolName() << "Error making unique filename: " + << ErrMsg << "\n"; exit(1); } - std::string SharedObject = compileSharedObject(SafeModuleBC); + + if (writeProgramToFile(SafeModuleBC.toString(), ToNotCodeGen)) { + errs() << "Error writing bitcode to `" << SafeModuleBC << "'\nExiting."; + exit(1); + } + std::string SharedObject = compileSharedObject(SafeModuleBC.toString()); delete ToNotCodeGen; - std::cout << "You can reproduce the problem with the command line: \n"; + outs() << "You can reproduce the problem with the command line: \n"; if (isExecutingJIT()) { - std::cout << " lli -load " << SharedObject << " " << TestModuleBC; + outs() << " lli -load " << SharedObject << " " << TestModuleBC; } else { - std::cout << " llc " << TestModuleBC << " -o " << TestModuleBC << ".s\n"; - std::cout << " gcc " << SharedObject << " " << TestModuleBC - << ".s -o " << TestModuleBC << ".exe -Wl,-R.\n"; - std::cout << " " << TestModuleBC << ".exe"; + outs() << " llc -f " << TestModuleBC << " -o " << TestModuleBC<< ".s\n"; + outs() << " gcc " << SharedObject << " " << TestModuleBC + << ".s -o " << TestModuleBC << ".exe"; +#if defined (HAVE_LINK_R) + outs() << " -Wl,-R."; +#endif + outs() << "\n"; + outs() << " " << TestModuleBC << ".exe"; } for (unsigned i=0, e = InputArgv.size(); i != e; ++i) - std::cout << " " << InputArgv[i]; - std::cout << "\n"; - std::cout << "The shared object was created with:\n llc -march=c " - << SafeModuleBC << " -o temporary.c\n" - << " gcc -xc temporary.c -O2 -o " << SharedObject + outs() << " " << InputArgv[i]; + outs() << '\n'; + outs() << "The shared object was created with:\n llc -march=c " + << SafeModuleBC << " -o temporary.c\n" + << " gcc -xc temporary.c -O2 -o " << SharedObject #if defined(sparc) || defined(__sparc__) || defined(__sparcv9) - << " -G" // Compile a shared library, `-G' for Sparc + << " -G" // Compile a shared library, `-G' for Sparc #else - << " -shared" // `-shared' for Linux/X86, maybe others + << " -fPIC -shared" // `-shared' for Linux/X86, maybe others #endif - << " -fno-strict-aliasing\n"; + << " -fno-strict-aliasing\n"; return false; }